servewaf: each decision heuristic is its own module (closes #195)

Each check servewaf runs on a request is a type in its own file behind
one interface, heuristic, and is registered in one of four ordered lists
in heuristics.go. Order and behaviour are unchanged.

Every refusal now logs heuristic, the name of the heuristic that made
it, and heuristic_figures, the figures it acted on. A ban by
refusal_limit or byte_limits after the answer logs after_answer_heuristic
and after_answer_heuristic_figures instead, so a line can name both. All
four are in docs/request-log.md, and SPEC.md names each heuristic at its
step.

Model: opus-5-5

Dockerfile

@@ -117,8 +117,9 @@ RUN git checkout --quiet --detach b4b2c785308b1ce785b6155c7fe5f16879080193 \
     && CGO_ENABLED=0 go build -trimpath -ldflags="-s -w" \
         -o /usr/local/bin/runsvinit .
 
-# The image an app's Dockerfile builds FROM, described under "Deployment"
-# in SPEC.md. It is the last stage, so a plain `docker build .` builds it.
+# The image, described under "Deployment" in SPEC.md. It runs rproxy unless
+# SMALLWEBWAF_COMMAND says servewaf, and an app's Dockerfile can build FROM it.
+# It is the last stage, so a plain `docker build .` builds it.
 #
 # ubuntu 26.04, 2026-09-27
 FROM ubuntu@sha256:f144425ff09be612d6d9ad965196e9cdc23dae1f42110a8a11a3e9a8198759f7
@@ -132,32 +133,11 @@ RUN mkdir /etc/sysusers.d \
     && echo 'u  _runit-log  -  "runit svlogd user"  /nonexistent  /sbin/nologin' \
         > /etc/sysusers.d/runit.conf
 
-# ca-certificates, nix-bin and runit, from Ubuntu's archive as it was at
-# the snapshot moment, which is never earlier than the Ubuntu image above.
-# apt checks every package against the snapshot's InRelease files, and
-# this step checks those against the hashes named here, which are those
-# of the amd64 archive: other architectures use Ubuntu's ports archive.
-# apt also fetches the live archive's InRelease files, which change daily
-# and which the install does not use. The snapshot service is HTTPS only
-# and this image has no CA certificates yet, so this step uses the Go
-# image's. The snapshot service answers 503 at times; apt retries a
-# failed download, waiting twice as long before each retry, and this
-# step gives it five retries, about half a minute in all, where its
-# default of three gives up after seven seconds.
-RUN --mount=type=bind,from=builder,source=/etc/ssl/certs/ca-certificates.crt,target=/tmp/go-image-ca.crt \
-    apt-get update --snapshot 20261001T000000Z \
-        -o Acquire::https::CaInfo=/tmp/go-image-ca.crt \
-        -o Acquire::Retries=5 \
-    && printf '%s\n' \
-        '45f95ce276cdba3e41870516a130e03c58b8b7a79e9546b0efe9e526d255740c  snapshot.ubuntu.com_ubuntu_20261001T000000Z_dists_resolute_InRelease' \
-        '802e675dd9de4c7f3916434a95e7c1d8eec0e82886622d7805ab19a2c6fe0365  snapshot.ubuntu.com_ubuntu_20261001T000000Z_dists_resolute-updates_InRelease' \
-        '64b3353f0bd4970b4f7271962245bcea9ff24d4cc7bea16b433f8a60e42ca3dd  snapshot.ubuntu.com_ubuntu_20261001T000000Z_dists_resolute-backports_InRelease' \
-        '1d5041572116a8b23aabf79ac7439ad8af83d57ad3fb0f9aa0d4523ec10c5908  snapshot.ubuntu.com_ubuntu_20261001T000000Z_dists_resolute-security_InRelease' \
-        | (cd /var/lib/apt/lists && sha256sum --check --strict) \
+# ca-certificates, nix-bin and runit, from Ubuntu's archive. apt fetches
+# them over plain HTTP and checks each one against the archive's signed
+# package lists, so no CA certificates are needed.
+RUN apt-get update \
     && DEBIAN_FRONTEND=noninteractive apt-get install --yes --no-install-recommends \
-        --snapshot 20261001T000000Z \
-        -o Acquire::https::CaInfo=/tmp/go-image-ca.crt \
-        -o Acquire::Retries=5 \
         ca-certificates nix-bin runit \
     && rm -rf /var/lib/apt/lists/*
 
@@ -197,11 +177,11 @@ RUN groupadd --system --gid 65532 smallwebwaf \
 
 # The state files' directory, SWWAF_STATE_DIR by default, where a volume
 # is mounted to keep them across deploys. The run script gives it to the
-# smallwebwaf user at each start.
+# smallwebwaf user at each start of servewaf.
 RUN mkdir /var/lib/smallwebwaf
 
-# The default rule file, in SWWAF_RULES_DIR by default, where an app's
-# Dockerfile can copy rule files of its own beside it.
+# The default rule file, in SWWAF_RULES_DIR by default, where a Dockerfile
+# built FROM this image can copy rule files of its own beside it.
 COPY share/rules.d/00-default.rules /etc/smallwebwaf/rules.d/00-default.rules
 
 # runsvinit starts runit's runsvdir on /etc/service, where Ubuntu's sv

Makefile

@@ -1,12 +1,13 @@
 .PHONY: bootstrap setup test lint fmt fmt-check tidy check docker hooks build \
-	run example-app gitea-requests
+	run example-app gitea-requests gitea-setup
 
 # Makefile targets are thin shims; the implementations live in script/
 # per the scripts-to-rule-them-all pattern (see the Entrypoints section
 # of README.md). tidy writes go.mod and go.sum as `go mod tidy` does,
 # which test checks. build and run are for working on the code by hand;
 # example-app checks the image with an app built on it; gitea-requests
-# reports the gitea requests the Core Rule Set refuses at the defaults.
+# reports the gitea requests the Core Rule Set refuses at the defaults;
+# gitea-setup checks the setup in deploy/gitea.
 
 bootstrap:
 	@script/bootstrap
@@ -49,3 +50,6 @@ example-app:
 
 gitea-requests:
 	@script/gitea-requests
+
+gitea-setup:
+	@script/gitea-setup

README.md

@@ -1,52 +1,48 @@
 # smallwebwaf
 
 `smallwebwaf` is an MIT-licensed web application firewall, written in Go by
-[@sneak](https://sneak.berlin), for one self-hosted web app. It runs inside the
-app's own container, in front of the app. It refuses the requests of scrapers,
-scanners and other abusers before they reach the app.
+[@sneak](https://sneak.berlin), for self-hosted web apps. It refuses the
+requests of scrapers, scanners and other abusers before they reach an app.
+
+## What it does
 
 A web application firewall reads each request on its way to a web app and
-refuses the ones that look like abuse. `smallwebwaf` is also a reverse proxy: it
-accepts requests on the app's behalf, passes them to the app, and passes the
-app's answers back.
+refuses the ones that look like abuse. `smallwebwaf` is one binary, shipped in
+one image, with two commands that do this together:
 
-It needs no setting. Every `SWWAF_` setting has a default chosen for a service
-on the open internet. [`SPEC.md`](SPEC.md) says how `smallwebwaf` behaves and
-why. The reference documents under [`docs/`](docs/) are listed under "Documents"
-below.
+- `smallwebwaf rproxy` is a small reverse proxy in front of one app. traefik
+  routes to it. It asks `servewaf` about each request, passes the allowed ones
+  to the app, and passes the app's answers back. It keeps nothing and never
+  touches disk.
+- `smallwebwaf servewaf` decides. It runs the checks and keeps the bans, the
+  counters and each client's history. One `servewaf` serves many sites: a client
+  banned through one site is refused on all of them, and its requests on all of
+  them count toward one set of limits.
 
-## What it protects against
+The site keeps answering while `servewaf` is down, slow or restarting: without
+an answer in time, `rproxy` passes the request to the app.
 
-- Scrapers that fetch every page of a site, all day. Rate limiting gives each
-  client 500 requests a minute, 20,000 an hour and 300,000 a day. That leaves
-  room for programmatic use of an API, such as an automation fleet on another
-  host. A fleet of about 20 agents makes about 120 requests a minute at its
-  busiest. A gitea page opened with an empty cache loads about 40 files, so a
-  few such first visits fit in the minute limit too. The minute limit catches,
-  within seconds, a client firing requests as fast as it can. The hour limit
-  catches a client that keeps up more than about 5.5 a second for an hour. The
-  day limit catches a client that keeps up 4 a second around the clock. Counting
-  cannot catch a client that stays under all three limits, such as one that
-  keeps up 3 a second; only the protections below can. Byte limits give each
-  client 4 GiB a minute, 20 GiB an hour and 200 GiB a day. A client over a limit
-  is refused and banned. The first ban lasts an hour. Each repeat within a day
-  makes the next ban three times as long. A ban that would last more than seven
-  days is permanent.
+It protects against:
+
+- Scrapers that fetch every page of a site, all day. Each client gets a limit on
+  requests and on bytes per minute, per hour and per day. The defaults leave
+  room for a person reading a site for hours. They catch a scraper that keeps up
+  one request every 2 seconds. A client over a limit is refused and banned: for
+  a while at first, for three times as long at each repeat, and permanently when
+  it keeps at it.
 - Scanners that probe for secrets, such as `/.env` or `/.git/config`. The
-  default rule file bans such a client for seven days at its first probe. Its
-  next request during the ban makes the ban permanent. The default rule file
-  does not cover probes for other apps, such as a WordPress login. A `ban` rule
-  of your own, or an entry in `SWWAF_TRAP_PATHS`, bans those the same way.
+  default rule file bans such a client at its first probe, and its next request
+  during the ban makes the ban permanent. Your own rules, or a list of trap
+  paths, ban probes for other apps, such as a WordPress login, the same way.
 - Attacks carried in a request's URL or headers, such as SQL injection and path
-  traversal. The OWASP Core Rule Set is a published set of rules that recognise
-  common web attacks. Coraza, a Go engine, runs those rules (see "Attack
-  detection" in [`SPEC.md`](SPEC.md)). A request the rules take for an attack is
-  refused.
+  traversal. The OWASP Core Rule Set, a published set of rules that recognise
+  common web attacks, runs on every request through Coraza, a Go engine. A
+  request the rules take for an attack is refused.
 - Abuse from networks and countries you do not want. You can:
     - refuse whole netblocks and countries;
     - give the clients of chosen networks and countries a fraction of every
       limit, so that they are banned sooner;
-    - refuse or limit clients on a blocklist or a DNS blocklist, or with a high
+    - refuse or limit clients on a blocklist, a DNS blocklist, or with a high
       AbuseIPDB score;
     - ban clients named by your own CrowdSec engine.
 - Slow and oversized requests. Every request and every answer has a time limit
@@ -54,29 +50,26 @@ below.
 
 For the operator, it:
 
-- writes one JSON log line for every request, saying what it did and why (see
-  [`docs/request-log.md`](docs/request-log.md));
-- sends alerts to a webhook, Slack or ntfy (see
-  [`docs/alerts.md`](docs/alerts.md));
-- serves Prometheus metrics (see [`docs/metrics.md`](docs/metrics.md));
+- logs each request as JSON lines, saying what it did and why;
+- sends alerts to a webhook, Slack or ntfy;
+- serves Prometheus metrics;
 - keeps its bans, counters and history in JSON files you can read and edit, so
-  that a restart loses nothing and a ban can be lifted with an editor (see
-  [`docs/state-files.md`](docs/state-files.md)).
+  that a restart loses nothing and a ban can be lifted with an editor.
 
 Not built, and not planned:
 
-- TLS and routing for several apps. Both stay with traefik, the reverse proxy in
-  front of the container.
+- TLS and routing by host name. Both stay with traefik, the reverse proxy in
+  front of `rproxy`.
 - Browser challenges such as captchas.
-- A web console.
+- A web console, or a configuration file.
 - Defence against floods large enough to fill the host's network link.
 
 ## Getting started
 
-Build the image from a clone. `make docker` runs the tests and the linter, then
-builds the image, tagged `smallwebwaf`. It builds for amd64, on an amd64 host
-only: the `Dockerfile` checks Ubuntu's package lists against the hashes of the
-amd64 archive.
+### The image
+
+No image is published. Build it from a clone. `make docker` runs the tests and
+the linter, then builds the image, tagged `smallwebwaf`.
 
 ```sh
 git clone https://git.eeqj.de/sneak/smallwebwaf.git
@@ -84,14 +77,44 @@ cd smallwebwaf
 make docker
 ```
 
-Push the image to a registry your hosts pull from. Then build the app's own
-image on it. The app's `Dockerfile` starts `FROM` the `smallwebwaf` image, named
-by digest, and adds:
+Push the image to a registry your hosts pull from, and name it there by digest.
+
+The image runs `rproxy` by default. To run `servewaf` from the same image, set
+the container's `SMALLWEBWAF_COMMAND` to `servewaf`. The image's health check
+follows the command: in `rproxy`'s container it passes once `rproxy` answers and
+the app accepts connections, whether or not `servewaf` answers; in `servewaf`'s
+container, once `servewaf` answers.
+
+### The usual setup: three containers
+
+The usual setup is three containers on one private network:
+
+- the app;
+- `rproxy`, in front of the app, which traefik routes to: `SWRP_WAF_BACKEND`
+  names `servewaf` and `SWRP_UPSTREAM_URL` names the app;
+- `servewaf`, with `SMALLWEBWAF_COMMAND=servewaf` and a volume at
+  `/var/lib/smallwebwaf` for its state files.
+
+Point traefik's labels at port 8080 of `rproxy`
+(`traefik.http.services.<name>.loadbalancer.server.port=8080`). Publish no port
+of the app or of `servewaf`. Anything on that network can reach the app around
+`rproxy`, and can ask `servewaf` questions, so the network holds only what you
+trust. Each further app adds its own container and its own `rproxy`, whose
+`SWRP_WAF_BACKEND` names the same `servewaf`. The "Smallest setup" and "In front
+of gitea" examples below show this shape.
+
+### `rproxy` in the app's container
+
+An app's image can instead be built on the `smallwebwaf` image, so that `rproxy`
+runs beside the app in one container. `servewaf` still runs in a container of
+its own. The app's `Dockerfile` starts `FROM` the `smallwebwaf` image, named by
+digest, and adds:
 
 - the app's binary;
 - the packages the app needs, from the nixpkgs in the image;
 - a user for the app;
-- a `run` script that starts the app listening on `127.0.0.1:8081`.
+- a `run` script that starts the app listening on `127.0.0.1:8081`, the default
+  of `SWRP_UPSTREAM_URL`.
 
 ```dockerfile
 # The smallwebwaf image, pinned by digest.
@@ -126,117 +149,567 @@ main "$@"
 ```
 
 Leave `ENTRYPOINT` and `USER` out of the app's `Dockerfile`. The image's own
-entrypoint starts `smallwebwaf` and the app side by side, each as its own user.
+entrypoint starts `rproxy` and the app side by side, each as its own user. Run
+the app's image with `SWRP_WAF_BACKEND` set. `deploy/example-app` is such an
+app, and the "`rproxy` beside the app" example below runs one.
 
-Deploy the app's image as you deploy any app. Point traefik's labels at port
-8080 (`traefik.http.services.<name>.loadbalancer.server.port=8080`). Mount a
-volume at `/var/lib/smallwebwaf`, so that bans and history survive a deploy. For
-example, with no setting:
+The app sees the headers traefik sent, with traefik's address added to
+`X-Forwarded-For`, from a TCP peer that is `rproxy`. So the app must trust
+`rproxy`'s address for forwarded headers. In a container of its own, `rproxy` is
+on the private network, which the usual default of a trusted-proxy setting
+covers. Beside the app, its address is `127.0.0.1` or `::1`, which the private
+ranges leave out, so the app's own setting must name them too, as `app.run`
+does.
 
-```sh
-docker run --detach --name app \
-    --volume app-smallwebwaf:/var/lib/smallwebwaf \
-    <registry>/app@sha256:<digest>
+### Checking that it works
+
+- `docker inspect --format '{{.State.Health.Status}}' <container>` says
+  `healthy` for each container of `smallwebwaf`.
+- A log line with `"msg":"starting"` gives the version, the address and every
+  setting in effect, with secrets masked.
+- A request to the site through traefik gets the app's answer.
+  `https://<site>/_smallwebwaf/healthz` answers `ok`. `servewaf`'s log lines
+  about the request have `"action":"forward"`.
+- To see a refusal without banning yourself, run `servewaf` with
+  `SWWAF_MODE=observe` and ask for `/.env`. The request reaches the app.
+  `servewaf`'s log lines have `"would_action":"banned"` and
+  `"rule_ids":["env-file"]`. A ban you get in `enforce` mode is lifted as
+  "Clients and bans" below describes.
+- With `SWWAF_METRICS_TOKEN` set, this answers with the metrics, from a host on
+  `servewaf`'s network:
+  `curl -H "Authorization: Bearer $TOKEN" http://servewaf:8080/_smallwebwaf/metrics`.
+- `make example-app` builds the image and an app on it, runs them, and checks
+  the whole exchange (see "Entrypoints").
+
+## Configuration
+
+Every setting is an environment variable, read once at start; changing one means
+restarting the container. `rproxy` reads only the `SWRP_` settings, and
+`servewaf` only the `SWWAF_` ones. Every setting but `SWRP_WAF_BACKEND` has a
+default, chosen for a service on the open internet. A setting that needs an
+account, a key, a token or an alert destination stays off until you give one.
+
+- Any `SWWAF_` setting can be given as a file instead, for secrets and long
+  lists: `SWWAF_ADMIN_TOKEN_FILE` names the file that holds `SWWAF_ADMIN_TOKEN`.
+  The file's contents are the value, less one newline at the end. Setting both
+  forms stops the start. `SWWAF_LOG_REMOTE_TLS_CA_FILE` already names a file, so
+  it has no `_FILE` form, and no `SWRP_` setting has one, since `rproxy` never
+  touches disk.
+- A duration is Go's syntax, with `d` for days: `90s`, `15m`, `24h`, `7d`.
+- A size is a number of bytes with an optional `K`, `M` or `G`, in powers of
+  1024: `512K`, `100M`, `5G`.
+- A count is a whole number of requests, such as `1000`.
+- A time in milliseconds is a whole number above zero, such as `2000`.
+- A list is comma separated. A list set to an empty value is an empty list, and
+  replaces the default.
+- A netblock is an address and a prefix length, such as `10.0.0.0/8`; a bare
+  address stands for itself alone. A country is a two-letter code in either
+  case, such as `de`. An AS number is `AS` and the number, such as `AS64496`. A
+  percentage is a whole number from 0 to 100. A path prefix starts with `/`.
+- `off` switches a limit, a threshold or a timeout off where the table says a
+  setting takes it.
+- An invalid setting stops the process at start with one log line naming the
+  variable and what is wrong with the value. The settings in effect are logged
+  on one line at start, with tokens, keys and webhook paths shown as `********`.
+
+Every setting the code reads, with its default:
+
+| Variable                                   | Default                                                                        | What it does                                                                                                                                                        |
+| ------------------------------------------ | ------------------------------------------------------------------------------ | ------------------------------------------------------------------------------------------------------------------------------------------------------------------- |
+| `SMALLWEBWAF_COMMAND`                      | `rproxy`                                                                       | Which command the image runs, and its health check checks: `rproxy` or `servewaf`.                                                                                  |
+| `SWRP_WAF_BACKEND`                         | required                                                                       | `servewaf`'s URL, such as `http://servewaf:8080`.                                                                                                                   |
+| `SWRP_UPSTREAM_URL`                        | `http://127.0.0.1:8081`                                                        | The app's URL: a scheme, a host and an optional port, nothing more.                                                                                                 |
+| `SWRP_LISTEN_ADDR`                         | `:8080`                                                                        | Where `rproxy` listens; leave the host part empty.                                                                                                                  |
+| `SWRP_TRUSTED_PROXIES`                     | `10.0.0.0/8,172.16.0.0/12,192.168.0.0/16`                                      | The netblocks whose `X-Forwarded-For` `rproxy` believes; set but empty, it believes none.                                                                           |
+| `SWRP_TIMEOUT_MS`                          | `2000`                                                                         | How long `rproxy` waits for `servewaf`'s answer to a question and to a report, in milliseconds.                                                                     |
+| `SWRP_DEFAULT_DISPOSITION`                 | `allow`                                                                        | What `rproxy` does with a request when `servewaf` cannot be reached or does not answer in time: `allow` passes it to the app, `deny` answers `503`.                 |
+| `SWRP_MAX_REQUEST_SIZE`                    | `100M`                                                                         | The largest request body, a size or `off`; a larger one is answered `413`.                                                                                          |
+| `SWRP_MAX_RESPONSE_SIZE`                   | `1G`                                                                           | The largest response body, a size or `off`; a larger one is answered `502`, or cut off once it has started.                                                         |
+| `SWRP_MAX_REQUEST_TIME_MS`                 | `60000`                                                                        | How long the visitor may take to send its request line and headers, and then the whole request to reach the app, in milliseconds or `off`.                          |
+| `SWRP_MAX_RESPONSE_TIME_MS`                | `1800000`                                                                      | How long the answer may take, from the end of the request to its last byte reaching the visitor, in milliseconds or `off`.                                          |
+| `SWWAF_LISTEN_ADDR`                        | `:8080`                                                                        | Where `servewaf` listens; leave the host part empty.                                                                                                                |
+| `SWWAF_INSTANCE_NAME`                      | the container's host name                                                      | The name in every line `servewaf` logs, and in every alert and metric, such as `fsn1/servewaf`.                                                                     |
+| `SWWAF_MODE`                               | `enforce`                                                                      | `observe` refuses nothing and makes no ban; each log line says what `enforce` would have done.                                                                      |
+| `SWWAF_IPV6_GROUP_PREFIX`                  | `64`                                                                           | The prefix length of the IPv6 netblock that counts as one client, from 32 to 128.                                                                                   |
+| `SWWAF_MAX_TRACKED_CLIENTS`                | `20000`                                                                        | The most clients kept, in memory and in `clients.json`; the least recently seen is dropped first.                                                                   |
+| `SWWAF_MAX_BANS`                           | `5000`                                                                         | The most bans `servewaf` keeps of its own; bans an admin made do not count.                                                                                         |
+| `SWWAF_ALLOW_NETS`                         | empty                                                                          | Netblocks whose clients skip every check, such as your monitoring.                                                                                                  |
+| `SWWAF_RATE_LIMIT_EXEMPT_NETS`             | empty                                                                          | Netblocks whose clients the request and byte limits neither count nor refuse.                                                                                       |
+| `SWWAF_DENY_NETS`                          | empty                                                                          | Netblocks whose clients are refused.                                                                                                                                |
+| `SWWAF_RATE_LIMIT_PER_MINUTE`              | `120`                                                                          | The most requests a client may make in a minute, a count or `off`; one more bans it.                                                                                |
+| `SWWAF_RATE_LIMIT_PER_HOUR`                | `1500`                                                                         | The most requests a client may make in an hour, a count or `off`; one more bans it.                                                                                 |
+| `SWWAF_RATE_LIMIT_PER_DAY`                 | `6000`                                                                         | The most requests a client may make in a day, a count or `off`; one more bans it.                                                                                   |
+| `SWWAF_RATE_LIMIT_EXEMPT_PATHS`            | empty                                                                          | Path prefixes whose requests the request and byte limits neither count nor refuse, such as `/assets/`.                                                              |
+| `SWWAF_BYTES_LIMIT_PER_MINUTE`             | `off`                                                                          | The most bytes a client's requests may carry in a minute, a size or `off`; the request that takes a client past any byte limit bans it.                             |
+| `SWWAF_BYTES_LIMIT_PER_HOUR`               | `50G`                                                                          | The most bytes a client's requests may carry in an hour, a size or `off`.                                                                                           |
+| `SWWAF_BYTES_LIMIT_PER_DAY`                | `100G`                                                                         | The most bytes a client's requests may carry in a day, a size or `off`.                                                                                             |
+| `SWWAF_BYTES_COUNT`                        | `both`                                                                         | Which body bytes the byte limits count: `response`, `request` or `both`.                                                                                            |
+| `SWWAF_ERROR_BURST_THRESHOLD`              | `30`                                                                           | The most refusals by a rule file, a trap path or the Core Rule Set a client may get in a minute, a count or `off`; one more bans it.                                |
+| `SWWAF_BAN_RESPONSE`                       | `403`                                                                          | How a refused client is answered: `403`, `429` or `close`, which drops the connection.                                                                              |
+| `SWWAF_LIMIT_BAN_DURATION`                 | `1h`                                                                           | The ban for a first broken limit.                                                                                                                                   |
+| `SWWAF_LIMIT_BAN_REPEAT_WINDOW`            | `24h`                                                                          | A limit broken again within this time after the last such ban ended gets a ban three times as long.                                                                 |
+| `SWWAF_MAX_BAN_DURATION`                   | `7d`                                                                           | A ban for a broken limit that would be longer than this is permanent instead.                                                                                       |
+| `SWWAF_ATTACK_BAN_DURATION`                | `7d`                                                                           | The ban for a first clear sign of attack: a `ban` rule or a trap path.                                                                                              |
+| `SWWAF_BAN_SCOPE_V4_PREFIX`                | `32`                                                                           | The prefix length of the netblock a ban on an IPv4 client covers, from 0 to 32.                                                                                     |
+| `SWWAF_LOOKUP_SOURCE`                      | `geojs`                                                                        | Where each client's AS number and country come from: `geojs`, a web service, `file`, or `off`.                                                                      |
+| `SWWAF_LOOKUP_DB_PATH`                     | empty                                                                          | The IPinfo Lite database file, in its `.mmdb` form, read while the source is `file`.                                                                                |
+| `SWWAF_LOOKUP_TIMEOUT`                     | `800ms`                                                                        | How long a request waits for its client's first GeoJS answer when a setting needs it, and how long a request to GeoJS may take.                                     |
+| `SWWAF_ADD_LOOKUP_HEADERS`                 | `false`                                                                        | `true` passes the app the client's AS number and country in `X-Client-ASN` and `X-Client-Country`.                                                                  |
+| `SWWAF_DENIED_COUNTRIES`                   | empty                                                                          | Countries whose clients are refused, such as `cn,ru`.                                                                                                               |
+| `SWWAF_EXCLUSIVELY_ALLOWED_COUNTRIES`      | empty                                                                          | When set, the only countries whose clients get through; a client the lookup cannot place is refused too.                                                            |
+| `SWWAF_ASN_LIMIT_PERCENT`                  | empty                                                                          | AS numbers whose clients get a percentage of every request and byte limit, such as `AS14061:50,AS16276:25`.                                                         |
+| `SWWAF_COUNTRY_LIMIT_PERCENT`              | empty                                                                          | The same by country, such as `cn:25`.                                                                                                                               |
+| `SWWAF_ASN_BYTES_PERCENT`                  | empty                                                                          | A percentage of the byte limits alone for the AS numbers listed, in place of their `SWWAF_ASN_LIMIT_PERCENT`.                                                       |
+| `SWWAF_COUNTRY_BYTES_PERCENT`              | empty                                                                          | A percentage of the byte limits alone for the countries listed, in place of their `SWWAF_COUNTRY_LIMIT_PERCENT`.                                                    |
+| `SWWAF_UNKNOWN_LIMIT_PERCENT`              | `100`                                                                          | The percentage of every limit a client without a country gets.                                                                                                      |
+| `SWWAF_ASN_LIMIT_PERCENT_URL`              | unset                                                                          | The URL of a text file of `AS<number>:<percent>` lines, fetched like a blocklist; where it and `SWWAF_ASN_LIMIT_PERCENT` both give a percentage, the lower applies. |
+| `SWWAF_RULES_DIR`                          | `/etc/smallwebwaf/rules.d`                                                     | The directory of the rule files, read at start and again when a file there changes.                                                                                 |
+| `SWWAF_RULES_ENABLED`                      | `true`                                                                         | `false` reads no rule file.                                                                                                                                         |
+| `SWWAF_TRAP_PATHS`                         | empty                                                                          | Paths only scanners ask for, such as `/wp-login.php,/xmlrpc.php`; a request for one bans the client.                                                                |
+| `SWWAF_WAF_MODE`                           | `block`                                                                        | What the Core Rule Set does with a match: `block` refuses it with `403`, `detect` only logs and alerts it, `off` runs no rule.                                      |
+| `SWWAF_WAF_PARANOIA_LEVEL`                 | `1`                                                                            | The Core Rule Set's paranoia level, from 1 to 4; each level up finds more attacks and takes more ordinary requests for attacks.                                     |
+| `SWWAF_WAF_ANOMALY_THRESHOLD`              | `5`                                                                            | The Core Rule Set score at which a request is a match, a whole number or `off`; one critical rule scores 5.                                                         |
+| `SWWAF_WAF_DISABLED_RULES`                 | `920340,920420,920440,920640,930130,930140`                                    | Core Rule Set rule ids switched off; a list you give replaces the default, so repeat these six to keep them off.                                                    |
+| `SWWAF_WAF_EXEMPT_PATHS`                   | empty                                                                          | Path prefixes the Core Rule Set does not inspect.                                                                                                                   |
+| `SWWAF_WAF_BODY_LIMIT`                     | `off`                                                                          | How much of a request body the Core Rule Set reads, a size up to `64K`; `off` reads none.                                                                           |
+| `SWWAF_BLOCKLIST_URLS`                     | empty                                                                          | Blocklists to fetch, text files of addresses and netblocks one to a line, such as `https://www.spamhaus.org/drop/drop.txt`.                                         |
+| `SWWAF_BLOCKLIST_REFRESH`                  | `24h`                                                                          | How long after a list was last tried it is fetched again, `1h` or more.                                                                                             |
+| `SWWAF_BLOCKLIST_ACTION`                   | `deny`                                                                         | What a client on a blocklist gets: `deny`, `limit:<percent>` of every limit, or `log`.                                                                              |
+| `SWWAF_DNSBL_ZONES`                        | empty                                                                          | DNS blocklists asked about each new client in the background, such as `dnsbl.dronebl.org`.                                                                          |
+| `SWWAF_DNSBL_RESOLVER`                     | unset                                                                          | The resolver the zones are asked through, an IP address with an optional port; unset, the host's resolver is used.                                                  |
+| `SWWAF_ABUSEIPDB_KEY`                      | unset                                                                          | The key of your AbuseIPDB account; set, a client that has committed an offence is checked in the background.                                                        |
+| `SWWAF_ABUSEIPDB_MIN_SCORE`                | `75`                                                                           | The least AbuseIPDB abuse confidence score, from 0 to 100, that is a hit.                                                                                           |
+| `SWWAF_ABUSEIPDB_DAILY_BUDGET`             | `900`                                                                          | The most AbuseIPDB checks made in a day.                                                                                                                            |
+| `SWWAF_CROWDSEC_LAPI_URL`                  | unset                                                                          | The local API of a CrowdSec engine you run, such as `http://172.17.0.1:8080`; its decision list is fetched every minute, and a listed client is banned.             |
+| `SWWAF_CROWDSEC_LAPI_KEY`                  | unset                                                                          | The key the engine gave for `smallwebwaf`, as `cscli bouncers add smallwebwaf` prints it; set with the URL, never alone.                                            |
+| `SWWAF_REPUTATION_ACTION`                  | `limit:25`                                                                     | What a client listed by a DNS blocklist, or scored a hit by AbuseIPDB, gets: `deny`, `limit:<percent>` or `log`.                                                    |
+| `SWWAF_REPUTATION_CACHE_TTL`               | `24h`                                                                          | How long a DNS blocklist verdict or an AbuseIPDB score is used.                                                                                                     |
+| `SWWAF_REPUTATION_TIMEOUT`                 | `2s`                                                                           | How long a DNS blocklist query or an AbuseIPDB check may take.                                                                                                      |
+| `SWWAF_STATE_DIR`                          | `/var/lib/smallwebwaf`                                                         | The directory of the state files, an absolute path.                                                                                                                 |
+| `SWWAF_STATE_WRITE_DELAY`                  | `10s`                                                                          | How long `bans.json` waits to be written after a ban is made, lifted or made permanent.                                                                             |
+| `SWWAF_STATE_COUNTER_INTERVAL`             | `15m`                                                                          | How often every state file is written.                                                                                                                              |
+| `SWWAF_LOG_LEVEL`                          | `info`                                                                         | The least severe of `servewaf`'s own messages that are written: `debug`, `info`, `warn` or `error`; request lines are always written.                               |
+| `SWWAF_LOG_REQUEST_HEADERS`                | `accept,accept-language,accept-encoding,content-type,origin,range`             | The request headers whose values the request log records; `Authorization` and `Cookie` are never recorded.                                                          |
+| `SWWAF_LOG_REMOTE_URL`                     | unset                                                                          | A syslog server that also gets every line `servewaf` writes: `syslog+udp://`, `syslog+tcp://` or `syslog+tls://` with a host and a port.                            |
+| `SWWAF_LOG_REMOTE_TLS_CA_FILE`             | unset                                                                          | A file of PEM certificates a `syslog+tls` server's certificate must chain to, instead of the host's own.                                                            |
+| `SWWAF_LOG_REMOTE_BUFFER`                  | `10000`                                                                        | The most lines held while they wait to be sent; past it, the oldest is dropped.                                                                                     |
+| `SWWAF_LOG_REMOTE_FACILITY`                | `local0`                                                                       | The syslog facility of each record sent.                                                                                                                            |
+| `SWWAF_LOG_REMOTE_APP_NAME`                | `SWWAF_INSTANCE_NAME`                                                          | The app name in each syslog record, 1 to 48 printable ASCII characters without a space.                                                                             |
+| `SWWAF_ADMIN_TOKEN`                        | unset                                                                          | The bearer token for the ban and client endpoints, at least 32 characters; unset, they answer `404`.                                                                |
+| `SWWAF_METRICS_TOKEN`                      | unset                                                                          | The bearer token for `/_smallwebwaf/metrics`, at least 32 characters; unset, the metrics are off.                                                                   |
+| `SWWAF_METRICS_TOP_N`                      | `50`                                                                           | How many AS numbers and how many countries get metric series of their own; the rest are summed as `other`.                                                          |
+| `SWWAF_ALERT_WEBHOOK_URL`                  | unset                                                                          | A webhook each alert is posted to as a JSON object.                                                                                                                 |
+| `SWWAF_ALERT_WEBHOOK_HEADERS`              | empty                                                                          | Headers sent with each post, a list of `Name:value`, such as `Authorization:Bearer <token>`.                                                                        |
+| `SWWAF_ALERT_SLACK_WEBHOOK_URL`            | unset                                                                          | A Slack incoming webhook each alert is posted to as a message.                                                                                                      |
+| `SWWAF_ALERT_NTFY_URL`                     | unset                                                                          | An ntfy topic each alert is published to, as its full URL, such as `https://ntfy.sh/my-alerts`.                                                                     |
+| `SWWAF_ALERT_NTFY_TOKEN`                   | unset                                                                          | An ntfy access token sent with each alert.                                                                                                                          |
+| `SWWAF_ALERT_EVENTS`                       | `ban,permanent_ban,waf_block,anomaly,reputation_hit,source_failure,file_error` | The events alerts are sent for; the hourly `summary` is sent whatever it says.                                                                                      |
+| `SWWAF_ALERT_COOLDOWN`                     | `15m`                                                                          | How long after an alert its repeats are held back and counted, a duration or `off`.                                                                                 |
+| `SWWAF_ALERT_MAX_PER_HOUR`                 | `60`                                                                           | The most alerts sent in an hour, a number or `off`; the rest are counted in the hour's `summary`.                                                                   |
+| `SWWAF_ANOMALY_CLIENT_REQUESTS_PER_MINUTE` | `off`                                                                          | Alert when one client makes more requests than this in a minute, a count.                                                                                           |
+| `SWWAF_ANOMALY_CLIENT_REQUESTS_PER_HOUR`   | `off`                                                                          | Alert when one client makes more requests than this in an hour, a count.                                                                                            |
+| `SWWAF_ANOMALY_CLIENT_BYTES_PER_MINUTE`    | `off`                                                                          | Alert when one client's requests carry more bytes than this in a minute, a size.                                                                                    |
+| `SWWAF_ANOMALY_CLIENT_BYTES_PER_HOUR`      | `off`                                                                          | Alert when one client's requests carry more bytes than this in an hour, a size.                                                                                     |
+| `SWWAF_ANOMALY_NET_REQUESTS_PER_MINUTE`    | `off`                                                                          | Alert when the netblock around a client makes more requests than this in a minute, a count.                                                                         |
+| `SWWAF_ANOMALY_NET_REQUESTS_PER_HOUR`      | `off`                                                                          | Alert when the netblock around a client makes more requests than this in an hour, a count.                                                                          |
+| `SWWAF_ANOMALY_NET_BYTES_PER_MINUTE`       | `off`                                                                          | Alert when the netblock around a client carries more bytes than this in a minute, a size.                                                                           |
+| `SWWAF_ANOMALY_NET_BYTES_PER_HOUR`         | `off`                                                                          | Alert when the netblock around a client carries more bytes than this in an hour, a size.                                                                            |
+| `SWWAF_ANOMALY_NET_V4_PREFIX`              | `24`                                                                           | The prefix length of the netblock around an IPv4 client that the `SWWAF_ANOMALY_NET_` thresholds count, from 0 to 32.                                               |
+| `SWWAF_ANOMALY_NET_V6_PREFIX`              | `48`                                                                           | The prefix length of the netblock around an IPv6 client that the `SWWAF_ANOMALY_NET_` thresholds count, from 0 to 128.                                              |
+| `SWWAF_ANOMALY_ASN_REQUESTS_PER_MINUTE`    | `off`                                                                          | Alert when one AS number makes more requests than this in a minute, a count.                                                                                        |
+| `SWWAF_ANOMALY_ASN_REQUESTS_PER_HOUR`      | `off`                                                                          | Alert when one AS number makes more requests than this in an hour, a count.                                                                                         |
+| `SWWAF_ANOMALY_ASN_BYTES_PER_MINUTE`       | `off`                                                                          | Alert when one AS number carries more bytes than this in a minute, a size.                                                                                          |
+| `SWWAF_ANOMALY_ASN_BYTES_PER_HOUR`         | `off`                                                                          | Alert when one AS number carries more bytes than this in an hour, a size.                                                                                           |
+| `SWWAF_ANOMALY_TOTAL_REQUESTS_PER_MINUTE`  | `off`                                                                          | Alert when the whole service gets more requests than this in a minute, a count.                                                                                     |
+| `SWWAF_ANOMALY_TOTAL_REQUESTS_PER_HOUR`    | `off`                                                                          | Alert when the whole service gets more requests than this in an hour, a count.                                                                                      |
+| `SWWAF_ANOMALY_TOTAL_BYTES_PER_MINUTE`     | `off`                                                                          | Alert when the whole service carries more bytes than this in a minute, a size.                                                                                      |
+| `SWWAF_ANOMALY_TOTAL_BYTES_PER_HOUR`       | `off`                                                                          | Alert when the whole service carries more bytes than this in an hour, a size.                                                                                       |
+| `SWWAF_WATCH_NETS`                         | empty                                                                          | Named netblocks the `SWWAF_WATCH_` thresholds count each as a whole, such as `office=203.0.113.0/24,scraper-x=198.51.100.0/22`.                                     |
+| `SWWAF_WATCH_REQUESTS_PER_MINUTE`          | `off`                                                                          | Alert when a watched netblock makes more requests than this in a minute, a count.                                                                                   |
+| `SWWAF_WATCH_REQUESTS_PER_HOUR`            | `off`                                                                          | Alert when a watched netblock makes more requests than this in an hour, a count.                                                                                    |
+| `SWWAF_WATCH_BYTES_PER_MINUTE`             | `off`                                                                          | Alert when a watched netblock carries more bytes than this in a minute, a size.                                                                                     |
+| `SWWAF_WATCH_BYTES_PER_HOUR`               | `off`                                                                          | Alert when a watched netblock carries more bytes than this in an hour, a size.                                                                                      |
+
+[`docs/settings.md`](docs/settings.md) gives the values each setting takes in
+full, and the limits that are fixed rather than settings.
+
+## docker-compose examples
+
+Each example is a complete `compose.yaml`. `smallwebwaf` is the tag
+`make docker` gives the image; on another host, use the name you pushed it
+under, by digest. Docker Compose puts the services on a private network of its
+own, where each reaches the others by service name. Only "In front of gitea"
+uses traefik. The other three publish `rproxy`'s port on the host, for trying it
+out.
+
+### Smallest setup
+
+One app, `rproxy` in front of it, and `servewaf` with a volume for its state
+files, every setting at its default.
+
+```yaml
+services:
+    app:
+        # Your app, which listens on port 8081.
+        image: registry.example/app@sha256:0000000000000000000000000000000000000000000000000000000000000000
+
+    rproxy:
+        image: smallwebwaf
+        environment:
+            SWRP_WAF_BACKEND: http://servewaf:8080
+            SWRP_UPSTREAM_URL: http://app:8081
+        ports:
+            - "8080:8080"
+
+    servewaf:
+        image: smallwebwaf
+        environment:
+            SMALLWEBWAF_COMMAND: servewaf
+        volumes:
+            - servewaf-state:/var/lib/smallwebwaf
+
+volumes:
+    servewaf-state:
 ```
 
-With no setting, the address of every new visitor is sent to GeoJS, a web
-service, to find its country and network. `SWWAF_LOOKUP_SOURCE=off` sends
-nothing. `SWWAF_LOOKUP_SOURCE=file`, with `SWWAF_LOOKUP_DB_PATH` naming a
-database file on your own host, looks addresses up in that file (see "Lookup of
-AS number and country" in [`SPEC.md`](SPEC.md)).
+### Custom per-address limits
 
-`deploy/example-app` is such an app. `make example-app` builds it and checks it
-(see "Checking that it works" below). To run `smallwebwaf` outside the image
-while working on it, see "Entrypoints" below.
+For a site with no API:
 
-## What happens to a request
+- tighter limits for everyone;
+- no limits for the office and the automation host;
+- no checks for monitoring;
+- a refused netblock;
+- a smaller share of the limits for two hosting networks and one country;
+- trap paths;
+- `429` for a refused client.
 
-`smallwebwaf` handles each request in fifteen steps, in this order. Once a step
-refuses a request, the steps after it are skipped, apart from step 15, and
-nothing of the request reaches the app. "What happens to a request" in
-[`SPEC.md`](SPEC.md) gives each step in full, under the same numbers.
+```yaml
+services:
+    app:
+        image: registry.example/app@sha256:0000000000000000000000000000000000000000000000000000000000000000
+
+    rproxy:
+        image: smallwebwaf
+        environment:
+            SWRP_WAF_BACKEND: http://servewaf:8080
+            SWRP_UPSTREAM_URL: http://app:8081
+        ports:
+            - "8080:8080"
+
+    servewaf:
+        image: smallwebwaf
+        environment:
+            SMALLWEBWAF_COMMAND: servewaf
+            # Monitoring skips every check.
+            SWWAF_ALLOW_NETS: 192.0.2.10
+            # The office and the automation host are never rate limited.
+            SWWAF_RATE_LIMIT_EXEMPT_NETS: 203.0.113.0/24,198.51.100.7
+            # A netblock that sends nothing wanted.
+            SWWAF_DENY_NETS: 198.51.100.128/25
+            # Tighter limits for everyone else: a small static site.
+            SWWAF_RATE_LIMIT_PER_MINUTE: "60"
+            SWWAF_RATE_LIMIT_PER_HOUR: "600"
+            SWWAF_RATE_LIMIT_PER_DAY: "3000"
+            # Hosting networks and one country get a share of those limits.
+            SWWAF_ASN_LIMIT_PERCENT: AS14061:50,AS16276:25
+            SWWAF_COUNTRY_LIMIT_PERCENT: cn:25
+            # Paths only scanners ask for; one request bans the client.
+            SWWAF_TRAP_PATHS: /wp-login.php,/xmlrpc.php
+            # Answer a refused client with 429 rather than 403.
+            SWWAF_BAN_RESPONSE: "429"
+            SWWAF_LIMIT_BAN_DURATION: 30m
+        volumes:
+            - servewaf-state:/var/lib/smallwebwaf
+
+volumes:
+    servewaf-state:
+```
+
+### In front of gitea
+
+gitea behind traefik, set up for a code forge:
+
+- the upload limits raised, in size and in time;
+- the response size limit raised, for clones over 1 GiB;
+- the Actions runners exempt from counting;
+- the default request and byte limits kept.
+
+`traefik` is the network traefik is on, made outside this file.
+
+```yaml
+services:
+    gitea:
+        # gitea 1.27.3, 2026-08-29
+        image: gitea/gitea@sha256:87a67ee09d3ae0d1df5fda5dcda3e2a1f9236a45b0a59025d6e00e46adc43bef
+        environment:
+            GITEA__server__ROOT_URL: https://git.example/
+            # The host and the port of the SSH clone URLs gitea shows.
+            GITEA__server__SSH_DOMAIN: git.example
+            GITEA__server__SSH_PORT: "2222"
+            # gitea's TCP peer is rproxy, on the private network.
+            GITEA__security__REVERSE_PROXY_TRUSTED_PROXIES: 10.0.0.0/8,172.16.0.0/12,192.168.0.0/16
+        volumes:
+            - gitea-data:/data
+        networks:
+            - site
+        ports:
+            # SSH does not pass through smallwebwaf.
+            - "2222:22"
+
+    rproxy:
+        image: smallwebwaf
+        environment:
+            SWRP_WAF_BACKEND: http://servewaf:8080
+            SWRP_UPSTREAM_URL: http://gitea:3000
+            # Pushes, LFS objects and image layers over 100 MiB, or slower
+            # than a minute, are cut off at the defaults.
+            SWRP_MAX_REQUEST_SIZE: 2G
+            SWRP_MAX_REQUEST_TIME_MS: "600000"
+            # A clone larger than 1 GiB is cut off at the default.
+            SWRP_MAX_RESPONSE_SIZE: 4G
+        networks:
+            - site
+            - traefik
+        labels:
+            traefik.enable: "true"
+            # rproxy is on two networks; traefik reaches it on this one.
+            traefik.docker.network: traefik
+            traefik.http.routers.git.rule: Host(`git.example`)
+            traefik.http.routers.git.entrypoints: websecure
+            traefik.http.routers.git.tls.certresolver: letsencrypt
+            traefik.http.services.git.loadbalancer.server.port: "8080"
+
+    servewaf:
+        image: smallwebwaf
+        environment:
+            SMALLWEBWAF_COMMAND: servewaf
+            SWWAF_INSTANCE_NAME: fsn1/servewaf
+            # The Actions runners ask for work all day; never count them.
+            SWWAF_RATE_LIMIT_EXEMPT_NETS: 10.0.4.0/24
+            # gitea never serves these; a request for one bans the client.
+            SWWAF_TRAP_PATHS: /wp-login.php,/xmlrpc.php,/wp-admin/
+        volumes:
+            - servewaf-state:/var/lib/smallwebwaf
+        networks:
+            - site
+
+networks:
+    site:
+    traefik:
+        external: true
+
+volumes:
+    gitea-data:
+    servewaf-state:
+```
+
+`deploy/gitea` holds a complete setup of gitea, traefik included, as a Docker
+Compose file. [`docs/gitea.md`](docs/gitea.md) explains it, and records what the
+defaults do in front of gitea, request by request.
+
+### `rproxy` beside the app
+
+The app is built on the `smallwebwaf` image, with `rproxy` inside its container.
+`app/` holds the `Dockerfile` and `app.run` from "`rproxy` in the app's
+container". `rproxy` answers `503` to every request while `servewaf` is down,
+and `servewaf`:
+
+- observes before it enforces;
+- looks addresses up in a local database rather than GeoJS;
+- sends alerts to ntfy;
+- reads its ntfy token from a file.
+
+```yaml
+services:
+    app:
+        # A Dockerfile built FROM the smallwebwaf image, with rproxy inside.
+        build: ./app
+        environment:
+            SWRP_WAF_BACKEND: http://servewaf:8080
+            # Answer 503 rather than pass a request on while servewaf is down.
+            SWRP_DEFAULT_DISPOSITION: deny
+        ports:
+            - "8080:8080"
+
+    servewaf:
+        image: smallwebwaf
+        environment:
+            SMALLWEBWAF_COMMAND: servewaf
+            SWWAF_INSTANCE_NAME: fsn1/servewaf
+            # Refuse nothing yet; log what enforce mode would have done.
+            SWWAF_MODE: observe
+            # Look addresses up in a local IPinfo Lite database, never GeoJS.
+            SWWAF_LOOKUP_SOURCE: file
+            SWWAF_LOOKUP_DB_PATH: /var/lib/ipinfo/ipinfo_lite.mmdb
+            # Alerts to an ntfy topic, with its token read from a file.
+            SWWAF_ALERT_NTFY_URL: https://ntfy.example/smallwebwaf
+            SWWAF_ALERT_NTFY_TOKEN_FILE: /etc/smallwebwaf/tokens/ntfy
+            SWWAF_ALERT_EVENTS: ban,permanent_ban,waf_block,source_failure,file_error
+        volumes:
+            - servewaf-state:/var/lib/smallwebwaf
+            - /srv/ipinfo:/var/lib/ipinfo:ro
+            - /srv/smallwebwaf/tokens:/etc/smallwebwaf/tokens:ro
+
+volumes:
+    servewaf-state:
+```
+
+The database is mounted by its directory, not by file, so that a replaced
+database is seen. A token file belongs to uid 65532, the `smallwebwaf` user,
+with mode `0400`. This one holds an access token the ntfy server issued, which
+`ntfy token add <user>` prints there:
+
+```sh
+mkdir -p /srv/smallwebwaf/tokens
+# <token> is the access token that ntfy printed.
+echo '<token>' > /srv/smallwebwaf/tokens/ntfy
+chown 65532:65532 /srv/smallwebwaf/tokens/ntfy
+chmod 0400 /srv/smallwebwaf/tokens/ntfy
+```
+
+## Design
+
+How it works inside. [`SPEC.md`](SPEC.md) gives every rule in full, and why.
+
+### What happens to a request
+
+A request goes through these steps, in this order. Once `servewaf` refuses a
+request, the steps after that are skipped, apart from the report, and nothing of
+the request reaches the app.
+
+`rproxy` takes the first two:
 
 1. The health check, `GET /_smallwebwaf/healthz`, is answered at once.
-2. The client is identified.
+2. The visitor's address is worked out from `X-Forwarded-For`, believed only
+   from `SWRP_TRUSTED_PROXIES`. `rproxy` sends `servewaf` the request as the
+   visitor sent it, with the first 64 KiB of its body.
+
+`servewaf` takes the checks:
+
 3. The static lists, `SWWAF_ALLOW_NETS` and `SWWAF_DENY_NETS`.
 4. The bans.
 5. The lookup of the client's AS number and country.
 6. The country lists.
 7. The reputation sources.
-8. The client's limit percentage.
+8. The client's limit percentage, from its AS number, its country or a
+   reputation hit.
 9. The rate limits.
 10. The trap paths.
 11. The rule files.
-12. The Core Rule Set.
-13. `smallwebwaf`'s own endpoints, under `/_smallwebwaf/`.
-14. The request is passed to the app.
-15. After the answer: the byte limits, the error burst and the client's history.
+12. The header limits, and then the Core Rule Set.
+13. A path under `/_smallwebwaf/` is answered `404`, so that the app never sees
+    that prefix.
 
-A refused visitor is answered with `SWWAF_BAN_RESPONSE`, `403` by default (see
-"Ban lengths, response and scope" in [`SPEC.md`](SPEC.md)). A `block` rule or a
-Core Rule Set match answers `403`. A missing or wrong token gets `401`. A
-request over a size or time limit gets the status for that limit, such as `413`
-for a body too large (see "Size and time limits" in [`SPEC.md`](SPEC.md)).
+`rproxy` takes the rest, with `servewaf` counting at the end:
 
-## Settings you are likely to touch
+14. The request is passed to the app, streaming.
+15. After the answer, `rproxy` sends `servewaf` a report with the status and the
+    bytes each way. For an allowed request, `servewaf` counts the bytes toward
+    the byte limits and adds the request to the client's history.
 
-Each setting is an environment variable of the app's container, such as
-`docker run -e SWWAF_MODE=observe ...`, read at start.
-[`docs/settings.md`](docs/settings.md) lists every setting, its default and the
-values it takes. The ones most deployments touch:
+A refused visitor is answered with `SWWAF_BAN_RESPONSE`. A `block` rule or a
+Core Rule Set match answers `403` and bans nobody, since the Core Rule Set has
+false positives; such refusals count toward `SWWAF_ERROR_BURST_THRESHOLD`
+instead. A request over the header limits of step 12 is answered `431`, and bans
+nobody either. `rproxy` itself answers `405` to a method it does not pass on,
+and the status for a size or time limit, such as `413` for a body too large.
 
-- `SWWAF_MODE=observe`: `smallwebwaf` makes no ban of its own, and refuses a
-  request only for a size or time limit or a missing or wrong token. A request
-  it would have refused is passed to the app, and its log line says what
-  `enforce` mode would have done. For trying a configuration before enforcing
-  it.
-- `SWWAF_ALLOW_NETS`: netblocks you trust, such as your monitoring. Their
-  clients are refused only for a size or time limit or a missing or wrong token.
-- `SWWAF_RATE_LIMIT_EXEMPT_NETS`: netblocks exempt from rate limiting and the
-  byte limits, such as a machine that talks to the app all day.
-- `SWWAF_TRAP_PATHS`: paths only scanners ask for, such as
-  `/wp-login.php,/xmlrpc.php` in front of a code forge. A request for one bans
-  the client.
-- `SWWAF_WAF_DISABLED_RULES`: Core Rule Set rule ids to switch off when a rule
-  refuses your app's ordinary requests. The log line names the rules a request
-  matched. Keep the six default ids in a list you give (see
-  [`docs/settings.md`](docs/settings.md)).
-- `SWWAF_REQUEST_MAX_BYTES`, `SWWAF_CLIENT_REQUEST_TIMEOUT` and
-  `SWWAF_UPSTREAM_REQUEST_TIMEOUT`: raise them for an app that takes uploads
-  over 100 MiB or slower than 60 seconds.
-- `SWWAF_LOOKUP_SOURCE`: `geojs` (the default), `file` or `off`, as above.
-- `SWWAF_ADMIN_TOKEN` and `SWWAF_METRICS_TOKEN`: switch on the ban endpoints and
-  the metrics. Give them as files to keep them from the app.
-- `SWWAF_ALERT_WEBHOOK_URL`, `SWWAF_ALERT_SLACK_WEBHOOK_URL` or
-  `SWWAF_ALERT_NTFY_URL`: where alerts go.
-- `SWWAF_INSTANCE_NAME`: the name in every log line, alert and metric, such as
-  `fsn1app1/gitea`.
+### Clients and bans
 
-## Checking that it works
+- A client is one IPv4 address or one IPv6 netblock of
+  `SWWAF_IPV6_GROUP_PREFIX`, since one abuser usually controls a whole /64.
+- Each limit is counted over a sliding window with a few integers per client.
+  The table of clients and the table of bans each have a bound
+  (`SWWAF_MAX_TRACKED_CLIENTS`, `SWWAF_MAX_BANS`), so memory is bounded too.
+- A ban refuses every request from its netblock until it ends. Requests refused
+  under a ban count toward no limit. A permanent ban ends only when an admin
+  lifts it.
+- Every ban carries notes: the client's AS number and country, the limit it
+  broke or the rule it matched, the request that caused it, and its earlier
+  bans. An admin adds, keeps or lifts a ban by editing `bans.json` or through
+  the ban endpoints (see [`docs/admin-endpoints.md`](docs/admin-endpoints.md)).
 
-- `docker inspect --format '{{.State.Health.Status}}' <container>` says
-  `healthy` once `smallwebwaf` answers and the app accepts connections. A log
-  line with `"msg":"starting"` gives the version, the address and every setting
-  in effect, with secrets masked.
-- A request to the site through traefik gets the app's answer, and its log line
-  has `"action":"forward"`. `https://<site>/_smallwebwaf/healthz` answers `ok`.
-- To see a refusal without banning yourself, run the container with
-  `SWWAF_MODE=observe` and ask for `/.env`. The request reaches the app. Its log
-  line has `"would_action":"banned"` and `"rule_ids":["env-file"]`. In `enforce`
-  mode the same request bans your address for seven days, and your next request
-  makes the ban permanent. Lift the ban by editing `bans.json` (see "Bans" in
-  [`SPEC.md`](SPEC.md)).
-- With `SWWAF_METRICS_TOKEN` set,
-  `curl -H "Authorization: Bearer $TOKEN" https://<site>/_smallwebwaf/metrics`
-  answers with the metrics.
-- `make example-app` builds the image and the example app on it, runs the app,
-  and checks it. It needs network access. It checks:
-    - the health check;
-    - a request forwarded to the app;
-    - a ban for a broken limit, and a ban for a probe made permanent;
-    - orderly stops with `sv stop` and `docker stop`;
-    - bans surviving a new container on the same volume;
-    - a setting given as a file.
+### Attack detection
+
+- The Core Rule Set reads the method, the URL with its query string, and the
+  headers of every request, and no body unless `SWWAF_WAF_BODY_LIMIT` is set. In
+  front of a code forge, bodies carry what people write and publish, which the
+  rules take for attacks.
+- `smallwebwaf` changes the Core Rule Set in six ways so that it lets ordinary
+  requests to a code forge through, such as git over HTTP and sign-in through
+  Git Credential Manager. No setting undoes them; "Attack detection" in
+  [`SPEC.md`](SPEC.md) lists them.
+- Rule files are plain text, one rule to a line, edited by hand and read again
+  while `servewaf` runs. The image ships one file of probes no real visitor
+  sends (see [`docs/rules.md`](docs/rules.md)).
+
+### State files
+
+`servewaf` keeps everything in memory, and the five JSON files in
+`SWWAF_STATE_DIR` hold a copy: `bans.json`, `clients.json`, `lookups.json`,
+`reputation.json` and `alerts.json`. Each is written whole, to a temporary file
+renamed over the real one, so a crash leaves a complete file. `servewaf` notices
+a file edited on disk and takes the edit in; an edit that does not parse is set
+aside as `<name>.bad`, and never stops the running process (see
+[`docs/state-files.md`](docs/state-files.md)).
+
+### The image and its processes
+
+- The image is built on Ubuntu 26.04 LTS, pinned by digest. Its Ubuntu packages
+  come from Ubuntu's archive, and nixpkgs is fixed at one release. An app's
+  `Dockerfile` installs a package with `nix-env -iA nixpkgs.<name>` and gets the
+  same package each time it is built (see [`docs/image.md`](docs/image.md)).
+- runit, a service supervisor, runs `smallwebwaf` as the `smallwebwaf` user (uid
+  and gid 65532) and starts it again when it exits. The `run` script of
+  `servewaf` gives the state directory to the `smallwebwaf` user at each start,
+  so a volume needs no change of owner.
+- `rproxy` and `servewaf` use no token between them. `servewaf`'s own endpoints,
+  under `/_smallwebwaf/`, are for your admin tools and your metrics collector,
+  at its own address on the private network; nothing routes the internet there.
+- `docker stop` gives requests in progress five seconds to finish. With `rproxy`
+  in the app's container, the app must keep answering for five seconds after
+  `SIGTERM` for that to help them.
+- Only faults found at start stop a process: an invalid setting, a rule file or
+  state file that does not parse, a lookup database that cannot be read, or an
+  address it cannot listen on. Once running, a failing lookup service,
+  reputation source or alert destination never takes `servewaf` down.
+
+### Packages
+
+- `cmd/smallwebwaf`: the binary, which only calls `internal/smallwebwaf`.
+- `internal/smallwebwaf`: the process, as the command it is given, and the
+  health check.
+- `internal/config`: reads the settings, the one place they are read.
+- `internal/rproxy`: the reverse proxy in front of one app.
+- `internal/servewaf`: `servewaf`'s server, which runs the checks and answers
+  its own endpoints.
+- `internal/ratelimit`, `internal/bans`, `internal/rules`, `internal/waf`,
+  `internal/lookup`, `internal/reputation`, `internal/anomaly` and
+  `internal/alerts`: one check or source each.
+- `internal/state`, `internal/requestlog`, `internal/remotelog` and
+  `internal/metrics`: the state files, the log lines, the syslog sender and the
+  metrics.
+
+## Rationale
+
+Small self-hosted sites receive a great deal of traffic nobody asked for:
+
+- scrapers that ignore `robots.txt` and crawl every commit of every repository
+  on a public git server;
+- scanners walking through lists of WordPress and `.env` paths;
+- credential-guessing bots.
+
+Most of it comes from a small number of hosting networks and countries. A
+single-person operation has no abuse desk and no CDN contract. It needs
+something small that can be put in front of its services and left alone.
+
+The existing tools each solve part of this. Rule-based firewalls catch attack
+payloads but do not limit request rates. Rate limiters count requests but cannot
+tell a residential visitor from a rented server farm. The products that do most
+of it want a database and a web console. None of them can say "clients from
+these networks are banned after half as many requests as anyone else".
+[`EVALUATION.md`](EVALUATION.md) goes through the candidates one by one.
 
 ## Entrypoints
 
@@ -276,102 +749,45 @@ on the host.
 - `script/install-precommit`: installs that hook. `make hooks`.
 - `script/build`: builds `bin/smallwebwaf` with the Go on your host.
   `make build`.
-- `script/run`: builds `bin/smallwebwaf` and runs it with the settings in your
-  environment, listening on port 8080 in front of an app at
-  `SWWAF_UPSTREAM_URL`. Its state files go in `bin/state` and its rule files are
-  those of `share/rules.d`, unless `SWWAF_STATE_DIR` and `SWWAF_RULES_DIR` say
-  otherwise. `make run`.
-- `script/example-app`: builds the image and the example app on it, runs it with
-  a volume, and checks it as "Checking that it works" above describes. Then it
-  removes the containers, volumes and images. Needs network access.
-  `make example-app`.
-- `script/gitea-requests`: builds the image and runs gitea 1.27.3 behind it at
-  the defaults. It sends through it a sample of gitea's ordinary use and the
-  requests the Core Rule Set is known to refuse, and prints what `smallwebwaf`
-  did with each. Needs network access, and a docker daemon that pushes to a
-  registry on `localhost` over plain HTTP. [`docs/gitea.md`](docs/gitea.md)
-  records the results. `make gitea-requests`.
-
-## Rationale
-
-Small self-hosted sites receive a great deal of traffic nobody asked for:
-
-- scrapers that ignore `robots.txt` and crawl every commit of every repository
-  on a public git server;
-- scanners walking through lists of WordPress and `.env` paths;
-- credential-guessing bots.
-
-Most of it comes from a small number of hosting networks and countries. A
-single-person operation has no abuse desk and no CDN contract. It needs
-something small that can be put in front of one service and left alone.
-
-The existing tools each solve part of this. Rule-based firewalls catch attack
-payloads but do not limit request rates. Rate limiters count requests but cannot
-tell a residential visitor from a rented server farm. The products that do most
-of it want several containers, a database and a web console. None of them can
-say "clients from these networks are banned after half as many requests as
-anyone else". That is the useful thing to say when nearly all abuse comes from a
-known list of AS numbers. [`EVALUATION.md`](EVALUATION.md) goes through the
-candidates one by one.
-
-`smallwebwaf` fills that gap with:
-
-- per-client limits that ban;
-- lower limits for the networks and countries abuse comes from;
-- bans that grow with repetition;
-- a log that is easy to search and ship;
-- one binary in the app's own container, with no database and no required
-  setting.
-
-## Design
-
-The `smallwebwaf` image is built on Ubuntu 26.04 LTS, pinned by digest, with
-nixpkgs fixed at one release. An app's `Dockerfile` installs a package with
-`nix-env -iA nixpkgs.<name>` and gets the same package each time it is built.
-[`docs/image.md`](docs/image.md) lists what the image holds and how each part is
-pinned.
-
-- runit, a service supervisor, runs `smallwebwaf` and the app side by side, each
-  as its own user, and starts either again when it exits. The app cannot touch
-  the state files or the process of `smallwebwaf`.
-- `smallwebwaf` listens on port 8080 and passes requests to the app on
-  `127.0.0.1:8081`. The app listens on `127.0.0.1` only, so nothing reaches it
-  except through `smallwebwaf`. `smallwebwaf`'s own endpoints are under
-  `/_smallwebwaf/`, on the same port.
-- The app sees the headers traefik sent, with traefik's address added to
-  `X-Forwarded-For`, from a TCP peer on `127.0.0.1`. So the app must trust
-  `127.0.0.1` and `::1` for forwarded headers, besides the private address
-  ranges.
-- Both processes start with the container's environment variables, so every
-  setting of this `smallwebwaf` process starts with `SWWAF_`, and the app can
-  read a token given as one. A token given as a file that only the `smallwebwaf`
-  user can read is out of its reach (see "Settings given as files" in
-  [`docs/settings.md`](docs/settings.md)).
-- The state files live in `/var/lib/smallwebwaf`. A volume mounted there keeps
-  them across a deploy.
-- `smallwebwaf servewaf` runs the same checks for the sites that ask it about
-  each request, and passes nothing to an app (see "`servewaf`" in
-  [`SPEC.md`](SPEC.md)).
-- `smallwebwaf rproxy` is the reverse proxy in front of one app that asks
-  `smallwebwaf servewaf` about each request. When `servewaf` cannot be connected
-  to, does not answer at all, or does not answer within `SWRP_TIMEOUT_MS`,
-  `SWRP_DEFAULT_DISPOSITION` decides. Its default, `allow`, keeps the site
-  answering. The settings of `rproxy` start with `SWRP_`, and it needs
-  `SWRP_WAF_BACKEND`, `servewaf`'s URL (see "`rproxy`" in [`SPEC.md`](SPEC.md)).
-- `docker stop` stops both processes at once. `smallwebwaf` gives the requests
-  in progress five seconds to finish, so the app must keep answering for five
-  seconds after `SIGTERM`.
-
-"Deployment" in [`SPEC.md`](SPEC.md) has the rest: the health check, what
-happens when a process stops, moving `smallwebwaf` to another port, and the
-forwarded headers. "Architecture" in [`SPEC.md`](SPEC.md) lists the packages and
-what each does.
+- `script/run`: builds `bin/smallwebwaf` and runs `servewaf` and `rproxy` on the
+  host, with the settings in your environment. `make run`. Unless your settings
+  say otherwise:
+    - `rproxy` listens on port 8080, in front of an app at
+      `http://127.0.0.1:8081`;
+    - `servewaf` listens on port 8090;
+    - its state files go in `bin/state`;
+    - its rule files are those of `share/rules.d`.
+- `script/example-app`: builds the image and the example app
+  (`deploy/example-app`) on it, runs the app with `rproxy` in its container and
+  `servewaf` in another, and checks them. Then it removes the containers, the
+  network, the volumes and the images. Needs network access. `make example-app`.
+  It checks:
+    - the health checks;
+    - a request passed to the app;
+    - a ban for a broken limit, and a ban for a probe made permanent;
+    - that only `servewaf`'s container changes the state directory's owner;
+    - with `servewaf` stopped, the app still answering through `rproxy`;
+    - with `servewaf` started again, bans applying again;
+    - orderly stops with `sv stop` and `docker stop`;
+    - bans surviving a new container on the same volume;
+    - a setting given as a file.
+- `script/gitea-requests`: builds the image and runs gitea 1.27.3 behind
+  `rproxy` and `servewaf`, three containers on one network. Every setting is at
+  its default, but for those that join the containers and
+  `SWWAF_LOG_REQUEST_HEADERS`, which adds the header that labels each request.
+  It sends through them a sample of gitea's ordinary use and the requests the
+  Core Rule Set is known to refuse, and prints what `servewaf` did with each.
+  Needs network access, and a docker daemon that pushes to a registry on
+  `localhost` over plain HTTP. `make gitea-requests`.
+- `script/gitea-setup`: builds the image, brings up the setup in `deploy/gitea`,
+  and checks it as [`docs/gitea.md`](docs/gitea.md) describes. Then it removes
+  the containers, the network, the volumes and the image it built. Needs network
+  access. `make gitea-setup`.
 
 ## TODO
 
-- Planned, as "Planned, not built" in [`SPEC.md`](SPEC.md) describes:
-    - sharing bans between the instances of several apps;
-    - sending the log over RELP.
+- Planned, as "Planned, not built" in [`SPEC.md`](SPEC.md) describes: sending
+  the log over RELP.
 
 ## Documents
 
@@ -379,8 +795,7 @@ what each does.
 - [`EVALUATION.md`](EVALUATION.md): what already exists, what each tool covers
   and misses, and why none was adopted.
 - [`REPO_POLICIES.md`](REPO_POLICIES.md): the policies this repository follows.
-- [`docs/settings.md`](docs/settings.md): every setting, its default and the
-  values it takes.
+- [`docs/settings.md`](docs/settings.md): every setting and the values it takes.
 - [`docs/rules.md`](docs/rules.md): the rule file format and the default file.
 - [`docs/admin-endpoints.md`](docs/admin-endpoints.md): the endpoints under
   `/_smallwebwaf/`, with examples.
@@ -391,7 +806,8 @@ what each does.
 - [`docs/state-files.md`](docs/state-files.md): the state files and what each
   holds.
 - [`docs/image.md`](docs/image.md): what the image holds and how it is pinned.
-- [`docs/gitea.md`](docs/gitea.md): `smallwebwaf` in front of gitea.
+- [`docs/gitea.md`](docs/gitea.md): `smallwebwaf` in front of gitea: the setup
+  in `deploy/gitea`, and what the defaults do there.
 
 ## License
 

cmd/smallwebwaf/main.go

@@ -1,8 +1,8 @@
-// Command smallwebwaf is a web application firewall for one app: it runs
-// between traefik and the app and passes requests through within its limits,
-// or, as `smallwebwaf servewaf`, answers rproxy's questions about them, or, as
-// `smallwebwaf rproxy`, is the reverse proxy that asks those questions.
-// Everything it does is in internal/smallwebwaf.
+// Command smallwebwaf is a web application firewall. `smallwebwaf rproxy` is
+// the reverse proxy in front of one app, which asks servewaf about each request.
+// `smallwebwaf servewaf` decides, for many sites, and keeps what lasts.
+// `smallwebwaf healthcheck` is the container's health check. Everything it does
+// is in internal/smallwebwaf.
 package main
 
 import (

deploy/gitea/compose.yaml

@@ -0,0 +1,135 @@
+# Gitea behind traefik, with rproxy and servewaf in front of it.
+# docs/gitea.md says what each setting here does and why. Before starting it:
+#   - set SMALLWEBWAF_IMAGE to the smallwebwaf image, named by digest;
+#   - replace git.example.org with the site's host name;
+#   - replace each 10.99.0 with the first three numbers of a /24 subnet that
+#     no other network on the host uses. The /24 must lie inside 10.0.0.0/8,
+#     172.16.0.0/12 or 192.168.0.0/16, because rproxy believes
+#     X-Forwarded-For only from those by default. Replace each fd10:99 with
+#     the first two hextets of an unused /64 subnet whose third and fourth
+#     hextets are 0, as in fd10:99::/64;
+#   - set GITEA_SECRET_KEY to the output of
+#     `docker run --rm <gitea's image below> gitea generate secret SECRET_KEY`,
+#     once per install, and keep it.
+# Then run `docker compose up --detach` in this directory.
+# script/gitea-setup checks this setup.
+
+name: gitea
+
+x-logging: &logging
+    driver: json-file
+    options:
+        max-size: 10m
+        max-file: "5"
+
+services:
+    traefik:
+        # traefik v3.7.17, 2026-11-03
+        image: traefik@sha256:68ae5fe5b64ca166704b746a9e8afcd385e36b3f569a5691401bf652d57b3748
+        # traefik replaces the X-Forwarded-For header a visitor sends. Keep it
+        # so: otherwise a visitor could name an address on the shared network,
+        # and skip servewaf's checks.
+        command:
+            - --providers.docker.exposedbydefault=false
+            - --entrypoints.web.address=:80
+            - --entrypoints.web.http.redirections.entrypoint.to=websecure
+            - --entrypoints.websecure.address=:443
+            # Until a certificate resolver is added here, as for your other
+            # sites, traefik answers with a certificate it made itself.
+            - --entrypoints.websecure.http.tls=true
+            # traefik's own limit of 60 seconds for a whole request would cut
+            # off an upload long before rproxy's limit of 30 minutes.
+            - --entrypoints.websecure.transport.respondingTimeouts.readTimeout=30m
+        ports:
+            - 80:80
+            - 443:443
+        volumes:
+            - /var/run/docker.sock:/var/run/docker.sock:ro
+        networks:
+            shared:
+                # Containers on the shared network find traefik under the
+                # site's name, and so reach it from their own address.
+                aliases:
+                    - git.example.org
+        restart: unless-stopped
+
+    gitea:
+        # gitea 1.27.3, 2026-08-29
+        image: gitea/gitea@sha256:87a67ee09d3ae0d1df5fda5dcda3e2a1f9236a45b0a59025d6e00e46adc43bef
+        environment:
+            GITEA__server__ROOT_URL: https://git.example.org/
+            # Gitea starts at its defaults, with SQLite, instead of showing its
+            # install page to whoever opens it first.
+            GITEA__security__INSTALL_LOCK: "true"
+            GITEA__security__SECRET_KEY: ${GITEA_SECRET_KEY:?set GITEA_SECRET_KEY, see docs/gitea.md}
+            # Accounts are made with `gitea admin user create`.
+            GITEA__service__DISABLE_REGISTRATION: "true"
+            # rproxy's addresses. Gitea then takes each visitor's address from
+            # the X-Real-Ip header traefik sets and rproxy passes on.
+            GITEA__security__REVERSE_PROXY_TRUSTED_PROXIES: 10.99.0.2,fd10:99::2
+        volumes:
+            - gitea-data:/data
+        networks:
+            - shared
+        restart: unless-stopped
+
+    rproxy:
+        image: ${SMALLWEBWAF_IMAGE:?set SMALLWEBWAF_IMAGE to the smallwebwaf image}
+        environment:
+            SWRP_WAF_BACKEND: http://servewaf:8080
+            SWRP_UPSTREAM_URL: http://gitea:3000
+            # Pushes, LFS objects, packages and release attachments of up to
+            # 2 GiB, sent in up to 30 minutes.
+            SWRP_MAX_REQUEST_SIZE: 2G
+            SWRP_MAX_REQUEST_TIME_MS: "1800000"
+            # 15 minutes for a clone or a download, half the default.
+            SWRP_MAX_RESPONSE_TIME_MS: "900000"
+        labels:
+            traefik.enable: "true"
+            traefik.http.routers.gitea.rule: Host(`git.example.org`)
+            traefik.http.routers.gitea.entrypoints: websecure
+            traefik.http.services.gitea.loadbalancer.server.port: "8080"
+        networks:
+            shared:
+                ipv4_address: 10.99.0.2
+                ipv6_address: fd10:99::2
+        logging: *logging
+        restart: unless-stopped
+
+    servewaf:
+        image: ${SMALLWEBWAF_IMAGE:?set SMALLWEBWAF_IMAGE to the smallwebwaf image}
+        environment:
+            SMALLWEBWAF_COMMAND: servewaf
+            # The containers on the shared network skip the checks. Add the
+            # address of an automation fleet on another host here too; without
+            # that, it is counted like any client.
+            SWWAF_ALLOW_NETS: 10.99.0.128/25,fd10:99:0:0:8000::/65
+            # In block mode the Core Rule Set refuses everyday Gitea searches
+            # and file names, and 31 refusals in a minute ban the address.
+            SWWAF_WAF_MODE: detect
+        volumes:
+            - servewaf-state:/var/lib/smallwebwaf
+        networks:
+            - shared
+        logging: *logging
+        restart: unless-stopped
+
+networks:
+    # The network traefik and Gitea share. Its containers get addresses in the
+    # upper half of each subnet, which servewaf lets skip the checks. Each
+    # subnet's gateway, the host's own address on it, stays out of that half:
+    # requests docker passes on from a published port can come from it.
+    shared:
+        enable_ipv6: true
+        ipam:
+            config:
+                - subnet: 10.99.0.0/24
+                  ip_range: 10.99.0.128/25
+                  gateway: 10.99.0.1
+                - subnet: fd10:99::/64
+                  ip_range: fd10:99:0:0:8000::/65
+                  gateway: fd10:99::1
+
+volumes:
+    gitea-data:
+    servewaf-state:

docs/admin-endpoints.md

@@ -1,8 +1,8 @@
 # Admin endpoints
 
 The endpoints under `/_smallwebwaf/`, what each takes and what each answers.
-"Admin endpoints" in [`SPEC.md`](../SPEC.md) says which checks they go through
-and how their tokens work.
+`smallwebwaf servewaf` answers them at its own address, on the private network.
+"Admin endpoints" in [`SPEC.md`](../SPEC.md) says how their tokens work.
 
 - `GET /_smallwebwaf/healthz`: `200` and `ok`, to anyone.
 - `GET /_smallwebwaf/metrics`: the metrics, for `SWWAF_METRICS_TOKEN` (see
@@ -20,40 +20,41 @@ and how their tokens work.
     - one that names an IPv4-mapped netblock, or an address with a zone.
 - `DELETE /_smallwebwaf/bans/<client>`: lifts every active ban covering the
   address `<client>`. It answers `404` when none is active.
-- `GET /_smallwebwaf/clients/<ip>`: what `smallwebwaf` knows of the client.
-  Under `client`, its counters and history as `clients.json` holds them, or
-  `null` when `clients.json` does not hold it. Under `bans`, every ban covering
-  the address, with its notes.
+- `GET /_smallwebwaf/clients/<ip>`: what `servewaf` knows of the client. Under
+  `client`, its counters and history as `clients.json` holds them, or `null`
+  when `clients.json` does not hold it. Under `bans`, every ban covering the
+  address, with its notes.
+- `POST /_smallwebwaf/report`: takes `rproxy`'s report, without a token. It
+  answers `204`, or `400` to a body that is no report (see "The report" in
+  [`SPEC.md`](../SPEC.md)).
+
+No check runs on these requests. A missing or wrong token is answered `401`. An
+endpoint whose token is unset answers `404`, as does any other path.
+
+`smallwebwaf rproxy` answers only the health check of these, at its own address.
+It asks `servewaf` about any other request under `/_smallwebwaf/`. One that
+passes the checks is answered `404`, so that the app never sees that prefix (see
+"`rproxy`" in [`SPEC.md`](../SPEC.md)).
 
 ## Examples
 
-With `SWWAF_ADMIN_TOKEN` set, and the token in `$TOKEN`:
+With `SWWAF_ADMIN_TOKEN` set, the token in `$TOKEN`, and `servewaf` reached as
+`servewaf:8080` on its network:
 
 ```sh
 # Every ban.
-curl -H "Authorization: Bearer $TOKEN" https://app.example/_smallwebwaf/bans
+curl -H "Authorization: Bearer $TOKEN" http://servewaf:8080/_smallwebwaf/bans
 
 # Ban 203.0.113.0/24 for seven days.
 curl -H "Authorization: Bearer $TOKEN" \
     --json '{"netblock": "203.0.113.0/24", "duration": "7d", "reason": "probes for logins"}' \
-    https://app.example/_smallwebwaf/bans
+    http://servewaf:8080/_smallwebwaf/bans
 
 # Lift the bans on 203.0.113.9.
 curl -H "Authorization: Bearer $TOKEN" -X DELETE \
-    https://app.example/_smallwebwaf/bans/203.0.113.9
+    http://servewaf:8080/_smallwebwaf/bans/203.0.113.9
 
-# What smallwebwaf knows of 203.0.113.9.
+# What servewaf knows of 203.0.113.9.
 curl -H "Authorization: Bearer $TOKEN" \
-    https://app.example/_smallwebwaf/clients/203.0.113.9
+    http://servewaf:8080/_smallwebwaf/clients/203.0.113.9
 ```
-
-## `servewaf`
-
-`smallwebwaf servewaf` answers these endpoints at its own address. No check runs
-on those requests (see "`servewaf`" in [`SPEC.md`](../SPEC.md)).
-
-## `rproxy`
-
-`smallwebwaf rproxy` answers only the health check, at its own address. It asks
-`servewaf` about any other request under `/_smallwebwaf/` (see "`rproxy`" in
-[`SPEC.md`](../SPEC.md)).

docs/alerts.md

@@ -6,7 +6,7 @@ back or dropped.
 
 ## Events
 
-- `ban`: a ban `smallwebwaf` made.
+- `ban`: a ban `servewaf` made.
 - `permanent_ban`: a permanent ban it made, or an existing ban made permanent by
   a request.
 - `waf_block`: the Core Rule Set scored a request at or over the threshold. The
@@ -34,9 +34,10 @@ on one line:
 
 ```json
 {
-    "instance": "fsn1app1/gitea",
+    "instance": "fsn1/servewaf",
     "time": "2026-10-06T12:00:50.123461Z",
     "event": "ban",
+    "host": "app.example",
     "client": "203.0.113.9",
     "netblock": "203.0.113.9/32",
     "asn": "",
@@ -78,9 +79,9 @@ on one line:
 
 - `instance`: `SWWAF_INSTANCE_NAME`. `time`: when the alert was raised. `event`:
   one of the events above.
-- `host`: the site of the request that raised the alert. Only `servewaf` sends
-  this field, since it serves many sites, and not for `source_failure`,
-  `file_error` and `summary`.
+- `host`: the site of the request that raised the alert, since one `servewaf`
+  serves many sites. It is left out of `source_failure`, `file_error` and
+  `summary`.
 - `client`: the address whose request raised the alert. Empty for
   `source_failure`, `file_error` and `summary`.
 - `netblock`: empty for `source_failure`, `file_error` and `summary`; otherwise
@@ -110,7 +111,7 @@ on one line:
 ## Slack and ntfy
 
 Slack and ntfy get a message with a title and a text. The title is the instance
-and the event, such as `fsn1app1/gitea: ban`. The text is the `reason`, then one
+and the event, such as `fsn1/servewaf: ban`. The text is the `reason`, then one
 line for each of these that the alert has:
 
 - the host, the client, the netblock and the country;

docs/gitea.md

@@ -1,51 +1,177 @@
 # smallwebwaf in front of gitea
 
-These notes record what `smallwebwaf` does in front of gitea at the default
-settings. They are observations, not requirements; the requirements are in
-[`SPEC.md`](../SPEC.md). `script/gitea-requests` runs gitea behind the image and
-sends through it a sample of gitea's ordinary use and the requests named below.
-It reports each request the Core Rule Set refuses, so that these notes can be
-checked again when gitea or the Core Rule Set changes version.
+`deploy/gitea/compose.yaml` runs gitea behind traefik, with `rproxy` and
+`servewaf` in front of it. This document says what that setup sets and why, and
+what the defaults would do without it. [`SPEC.md`](../SPEC.md) says how
+`smallwebwaf` behaves.
 
-## What the defaults cover
+## The setup
 
-- SSH access to gitea does not pass through `smallwebwaf` and is not protected
-  by it.
-- A clone is a response. It fits the defaults of 30 minutes and 1 GiB unless the
-  repository is large or the link slow. A repository whose clone is larger than
-  1 GiB needs `SWWAF_RESPONSE_MAX_BYTES` raised, and the byte limits with it
-  ("Byte limits, per client" in `SPEC.md`).
-- A push is a request, and so is every other upload:
-    - a git push;
-    - an LFS object;
-    - a container image layer;
-    - a package file;
-    - a release attachment.
+Four containers share one Docker network, the shared network:
 
-    At the defaults, an upload larger than 100 MiB or taking more than 60
-    seconds is cut off ("Size and time limits" in `SPEC.md`). A gitea that takes
-    large uploads needs `SWWAF_REQUEST_MAX_BYTES`,
-    `SWWAF_CLIENT_REQUEST_TIMEOUT` and `SWWAF_UPSTREAM_REQUEST_TIMEOUT` raised
-    to fit.
+- traefik, which routes the site's HTTPS requests to `rproxy`, and redirects
+  plain HTTP to HTTPS;
+- `rproxy`, in front of gitea;
+- gitea 1.27.3, as its image comes;
+- `servewaf`, with a volume for its state files.
 
-- Archive download and blame or history pages are what scrapers hammer. The
-  request limits do most of the work there.
-- An Actions runner that reaches gitea through `smallwebwaf` sends requests all
-  day. One older than version 0.4 (April 2026) asks for work every 2 seconds,
-  43,200 requests a day. While it runs a job, it reports the job's log and state
-  every second instead, two requests a second. So one runner busy all day sends
-  120 requests a minute and 172,800 a day, under the request limits. Two such
-  runners on one address, each busy all day, make 345,600 and pass the day limit
-  of 300,000. Three busy at once make 21,600 an hour and pass the hour limit of
-  20,000. Five busy at once make 600 a minute and pass the minute limit of 500.
-  Their address is then banned, their running jobs fail, and each repeat within
-  a day makes the ban longer. Newer runners ask for work less often. Put the
-  runners' addresses in `SWWAF_RATE_LIMIT_EXEMPT_NETS`.
+To start it:
 
-## What the Core Rule Set lets through
+1. In `deploy/gitea/compose.yaml`, replace `git.example.org` with the site's
+   host name.
+2. Replace each `10.99.0` with the first three numbers of a `/24` subnet that no
+   other network on the host uses. The `/24` must lie inside `10.0.0.0/8`,
+   `172.16.0.0/12` or `192.168.0.0/16`, because `rproxy` believes
+   `X-Forwarded-For` only from those by default. Replace each `fd10:99` with the
+   first two hextets of an unused `/64` subnet whose third and fourth hextets
+   are 0, as in `fd10:99::/64`.
+3. Set `SMALLWEBWAF_IMAGE` to the `smallwebwaf` image, named by digest.
+4. Set `GITEA_SECRET_KEY` to the output of
+   `docker run --rm <gitea's image> gitea generate secret SECRET_KEY`, with
+   gitea's image as `deploy/gitea/compose.yaml` names it. Do this once per
+   install, and keep the key.
+5. Run `docker compose up --detach` in `deploy/gitea`.
+6. Make gitea's first user with `gitea admin user create`, in gitea's container,
+   as the user `git`.
 
-At the defaults, the Core Rule Set lets gitea's ordinary use through, apart from
-the refusals in the next section:
+Sign-up is off: accounts are made with `gitea admin user create`. gitea starts
+at its defaults, with SQLite. traefik answers with a certificate it made itself
+until you add a certificate resolver, as for your other sites. SSH to gitea does
+not pass through `smallwebwaf`; publish gitea's SSH port yourself if you use it.
+
+`make gitea-setup` checks the setup. It builds the image, brings the setup up
+under a name of its own, and checks:
+
+- that a page load, a push and a clone sent through traefik pass through
+  `rproxy`, and that `servewaf` checks them;
+- that gitea logs the visitor's address, not `rproxy`'s;
+- that a request from a container on the shared network skips the checks;
+- that with `servewaf` stopped, gitea still answers through `rproxy`.
+
+## Uploads and downloads
+
+An upload is a request:
+
+- a git push;
+- an LFS object;
+- a container image layer;
+- a package file;
+- a release attachment.
+
+The setup lets an upload of up to 2 GiB, sent in up to 30 minutes, through:
+
+- `SWRP_MAX_REQUEST_SIZE` is `2G`. At the default, an upload over 100 MiB is cut
+  off.
+- `SWRP_MAX_REQUEST_TIME_MS` is `1800000`, 30 minutes. At the default, an upload
+  that takes over 60 seconds is cut off.
+- traefik's `readTimeout` is 30 minutes. traefik's own default of 60 seconds for
+  a whole request would cut off an upload first.
+
+A clone or a download is a response:
+
+- `SWRP_MAX_RESPONSE_TIME_MS` is `900000`, 15 minutes, half the default. A clone
+  or download that takes longer is cut off.
+- `SWRP_MAX_RESPONSE_SIZE` stays at its default, 1 GiB. A repository whose clone
+  is larger needs it raised.
+
+The byte limits stay at their defaults: no minute limit, 50 GiB an hour and 100
+GiB a day.
+
+## The checks
+
+`SWWAF_WAF_MODE` is `detect`. The Core Rule Set then logs a match, with its rule
+ids, and refuses nothing. In `block` mode, the default, it refuses everyday
+gitea searches and file names. The section "What the Core Rule Set refuses in
+`block` mode" below lists them. Each such refusal counts toward the error burst,
+so 31 in one minute ban the address.
+
+Every other check stays at its default. A client may make 120 requests a minute,
+1,500 an hour and 6,000 a day. Archive downloads and blame and history pages are
+what scrapers hammer, and these limits do most of the work there.
+
+## The shared network
+
+Containers on the shared network skip `servewaf`'s checks:
+
+- The shared network's subnets are `10.99.0.0/24` and `fd10:99::/64`. Docker
+  gives its containers addresses in the upper half of each, `10.99.0.128/25` and
+  `fd10:99:0:0:8000::/65`, which `SWWAF_ALLOW_NETS` names.
+- traefik is known on the shared network by the site's host name. So a container
+  there that asks for the site reaches traefik from its own address. An
+  automation fleet in such a container skips the checks.
+- Each subnet's gateway, `10.99.0.1` and `fd10:99::1`, is the host's own address
+  on it. Requests docker passes on from a published port can come from the
+  gateway, so the gateways are left out of `SWWAF_ALLOW_NETS`. The network has
+  IPv6, so a visitor over IPv6 reaches traefik from its own address, and
+  `servewaf` checks it as itself.
+- A container on the shared network that asks for the site at the host's public
+  address arrives from the gateway. It is checked like any visitor.
+- A fleet on another host can have its address added to `SWWAF_ALLOW_NETS`.
+  Without that, it is counted like any client.
+- traefik replaces the `X-Forwarded-For` a visitor sends, by default. Keep it
+  so: otherwise a visitor could name an address on the shared network, and skip
+  the checks.
+- Anything on the shared network can reach gitea and `servewaf` around `rproxy`.
+  Put only containers you trust on it.
+
+## gitea's settings
+
+- `REVERSE_PROXY_TRUSTED_PROXIES` names `rproxy`'s fixed addresses, `10.99.0.2`
+  and `fd10:99::2`. gitea then takes each visitor's address from the `X-Real-Ip`
+  header, which traefik sets and `rproxy` passes on. Without it, gitea logs
+  every visitor as `rproxy`.
+- `INSTALL_LOCK` is `true`, as "The setup" above says.
+
+## Methods
+
+`rproxy` passes on only these methods: `GET`, `HEAD`, `POST`, `OPTIONS`, `PUT`,
+`DELETE`, `PATCH` and `QUERY`. gitea 1.27.3 needs no other. Its routes use:
+
+- pages and the API: `GET`, `HEAD`, `POST`, `PUT`, `PATCH` and `DELETE`;
+- git's push, clone and fetch over HTTP: `GET`, `POST` and `OPTIONS`;
+- LFS: `GET`, `POST` and `PUT`;
+- the container registry and the other package registries: `GET`, `HEAD`,
+  `POST`, `PUT`, `PATCH` and `DELETE`;
+- Actions runners: `POST`.
+
+## The log
+
+`rproxy` and `servewaf` write each query string to the log whole. A token sent
+in the query string, as `?token=`, is then in the log. Send it in the
+`Authorization` header instead.
+
+## Actions runners
+
+A runner on the shared network skips the checks. One on another host is counted
+like any client. A runner older than version 0.4 (April 2026) asks for work
+every 2 seconds, 1,800 requests an hour. While it runs a job, it reports the
+job's log and state every second instead, two requests a second.
+
+So one idle runner makes 1,800 requests an hour, more than the hour limit of
+1,500. A busy one, at two requests a second, passes the minute limit of 120
+within two minutes. Its address is then banned, its running jobs fail, and each
+repeat within a day makes the ban longer. Newer runners ask for work less often.
+Put the runners' addresses in `SWWAF_RATE_LIMIT_EXEMPT_NETS`.
+
+## What the Core Rule Set refuses in `block` mode
+
+These notes record what the Core Rule Set does in front of gitea in `block`
+mode, at the other defaults. They are observations, not requirements.
+`script/gitea-requests` runs gitea behind `rproxy` and `servewaf` at the
+defaults. It sends through them a sample of gitea's ordinary use and the
+requests named below. It reports each request the Core Rule Set refuses, so that
+these notes can be checked again when gitea or the Core Rule Set changes
+version. In `detect` mode, as the setup runs it, the same requests are logged
+with their rule ids, and pass.
+
+Each refusal answers only that request ("Bans" in `SPEC.md` says what it counts
+toward). The request log names the rule in `waf_rule_ids`, which
+`SWWAF_WAF_DISABLED_RULES` can switch off.
+
+### What it lets through
+
+The Core Rule Set lets gitea's ordinary use through, apart from the refusals in
+the sections after this one:
 
 - browsing and views of files in a repository, with their history, blame and the
   file tree;
@@ -60,12 +186,6 @@ the refusals in the next section:
   editor, code included, since no body is read;
 - the page gitea shows after a change, with its message naming what was done.
 
-## What the Core Rule Set still refuses
-
-Each refusal answers only that request ("Bans" in `SPEC.md` says what it counts
-toward). The request log names the rule in `waf_rule_ids`, which
-`SWWAF_WAF_DISABLED_RULES` can switch off.
-
 ### A query string that reads as an attack
 
 Most often this is a search. A search term is a query parameter, which the Core
@@ -183,7 +303,7 @@ the runner. The error burst ("Attack detection" in `SPEC.md`) bans it after more
 than 30 such refusals from its address in a minute, as when many jobs upload at
 once. `actions/upload-artifact@v4` does not send the header.
 
-## What body inspection refuses
+### What body inspection refuses
 
 With `SWWAF_WAF_BODY_LIMIT` set, the Core Rule Set reads request bodies too. In
 front of gitea it then refuses these, until their rule ids, named in the request
@@ -195,7 +315,7 @@ log, are added to `SWWAF_WAF_DISABLED_RULES`:
 - PyPI uploads (922130);
 - attachments named like `debug.log` or `config.yml` (932180).
 
-## What `script/gitea-requests` sends
+### What `script/gitea-requests` sends
 
 Of the requests above, the script sends:
 

docs/image.md

@@ -1,14 +1,14 @@
 # What the image holds
 
-The contents of the `smallwebwaf` image, and how each part is pinned.
+The contents of the `smallwebwaf` image, and how each part is pinned. The image
+runs `rproxy` by default, or `servewaf` with `SMALLWEBWAF_COMMAND=servewaf`.
 "Deployment" in [`SPEC.md`](../SPEC.md) says why each part is there and why it
 is pinned that way.
 
 ## Contents
 
 - Ubuntu 26.04 LTS, pinned by digest.
-- `ca-certificates`, `nix-bin` and `runit` from Ubuntu, from the snapshot of its
-  archive at `20261001T000000Z`.
+- `ca-certificates`, `nix-bin` and `runit` from Ubuntu's archive.
 - Nix, with nixpkgs `nixos-26.05.11045.774debe7a0d1` set up for root as
   `nixpkgs`. No Nix daemon; `build-users-group =` in `/etc/nix/nix.conf`. Root's
   Nix profile, `/nix/var/nix/profiles/default/bin`, last on the `PATH`.
@@ -18,16 +18,15 @@ is pinned that way.
 - The `smallwebwaf` binary, and the user `smallwebwaf` (uid and gid 65532).
 - The service directory `/etc/service/smallwebwaf`, with the `run` script
   `share/smallwebwaf.run`.
-- `/var/lib/smallwebwaf` for the state files, and `/etc/smallwebwaf/rules.d`
-  with the default rule file `share/rules.d/00-default.rules`.
+- `/var/lib/smallwebwaf` for `servewaf`'s state files, and
+  `/etc/smallwebwaf/rules.d` with the default rule file
+  `share/rules.d/00-default.rules`.
 - `EXPOSE 8080`, and the `HEALTHCHECK` that runs `smallwebwaf healthcheck`.
 
 ## Pins
 
-- Ubuntu's packages: the snapshot service, `--snapshot 20261001T000000Z` on both
-  `apt-get update` and `apt-get install`. The SHA-256 hash of each of the
-  snapshot's `InRelease` files is named in the `Dockerfile` and checked after
-  `apt-get update`. The hashes are the amd64 archive's.
+- Ubuntu's packages are not pinned: they come from the live archive, whose
+  packages change with every update.
 - nixpkgs: the release file `nixexprs.tar.xz` of
   `nixos-26.05.11045.774debe7a0d1` on `releases.nixos.org`, named with its
   SHA-256 hash.

docs/metrics.md

@@ -1,8 +1,9 @@
 # The metrics
 
-What `GET /_smallwebwaf/metrics` answers with. "Metrics endpoint" in
-[`SPEC.md`](../SPEC.md) describes the endpoint. Prometheus keeps the `instance`
-label as `exported_instance` unless the scrape sets `honor_labels: true`.
+What `GET /_smallwebwaf/metrics` answers with, at `servewaf`'s own address.
+"Metrics endpoint" in [`SPEC.md`](../SPEC.md) describes the endpoint. Prometheus
+keeps the `instance` label as `exported_instance` unless the scrape sets
+`honor_labels: true`. `rproxy` has no metrics.
 
 ## Traffic
 
@@ -11,14 +12,13 @@ label as `exported_instance` unless the scrape sets `honor_labels: true`.
   `action`;
 - `smallwebwaf_request_duration_seconds` and
   `smallwebwaf_upstream_duration_seconds`, as histograms;
-- `smallwebwaf_requests_in_flight`.
+- `smallwebwaf_requests_in_flight`: the questions and requests to its own
+  endpoints that `servewaf` is handling.
 
 ## Limits and bans
 
 - `smallwebwaf_rate_limit_hits_total`, by `window` and by `kind` (`requests`,
   `bytes` or `refusals`);
-- `smallwebwaf_size_and_time_limit_hits_total`, by `limit`, the setting passed.
-  `servewaf`'s header limits have no setting, so it leaves them out;
 - `smallwebwaf_offences_total`, by `kind`;
 - `smallwebwaf_bans_made_total`, by `cause`;
 - `smallwebwaf_active_bans` and `smallwebwaf_permanent_bans`.
@@ -81,11 +81,11 @@ By `file`:
   `smallwebwaf_alerts_dropped_total`;
 - Go's own `go_` metrics and the process's `process_` metrics.
 
-## `servewaf`
+## When a request is counted
 
-`smallwebwaf servewaf` counts a denied request at its decision. It counts an
-allowed request when its report comes, with the status, bytes and times the
-report gives. These are not counted:
+`servewaf` counts a denied request at its decision, and a request to its own
+endpoints when it is answered. It counts an allowed request when its report
+comes, with the status, bytes and times the report gives. These are not counted:
 
 - a report itself;
 - an allowed request whose report never comes;

docs/request-log.md

@@ -1,124 +1,9 @@
 # The request log's fields
 
-The fields of the JSON object `smallwebwaf` writes for each request. "Request
-log" in [`SPEC.md`](../SPEC.md) says when a line is written and how the log is
-sent to a syslog server. A field that does not apply to a request is left out.
-`smallwebwaf rproxy` writes a shorter line, which "`rproxy`'s line" below gives.
-
-## Example
-
-```
-{"type":"request","time":"2026-10-03T12:00:00.123Z","instance":"fsn1app1/gitea","client_ip":"203.0.113.9","method":"GET","scheme":"https","host":"app.example","path":"/","query":"","protocol":"HTTP/1.1","status":200,"request_bytes":0,"response_bytes":5120,"referer":"","user_agent":"curl/8.9.1","request_id":"7Q2NHZ4KJ3VXW5YB6R3MEFTD2A","peer_ip":"172.18.0.2","forwarded_for":"203.0.113.9","client_group":"203.0.113.9/32","asn":"AS64496","as_name":"Example Net","country":"DE","request_headers":{"accept":"*/*"},"response_content_type":"text/html; charset=utf-8","upstream_status":200,"action":"forward","counts":{"minute":1,"hour":12,"day":40,"minute_bytes":5120,"hour_bytes":61440,"day_bytes":204800},"duration_total":3.217,"duration_checks":0.041,"duration_upstream_connect":0.052,"duration_upstream_first_byte":2.874,"duration_upstream_total":3.104}
-```
-
-## Every line
-
-Every line but `rproxy`'s has:
-
-- `type`: `request` (the process's own messages have `process`);
-- the standard web log fields;
-- `request_id`, `peer_ip` and `client_group`;
-- `asn`, `as_name` and `country`;
-- `action` and `duration_total`.
-
-## Standard web log fields
-
-- `time`: when the request arrived, RFC 3339 with milliseconds, in UTC;
-- `instance`: `SWWAF_INSTANCE_NAME`;
-- `client_ip`, `method`, `scheme`, `host`, `path`, `query`, `protocol`;
-- `status`: what the client was sent, `0` if nothing;
-- `request_bytes` and `response_bytes`: body bytes each way;
-- `referer` and `user_agent`.
-
-## Request detail
-
-- `request_id`: the `X-Request-ID` a trusted proxy sent, or a new random one of
-  26 letters and digits.
-- `peer_ip`: the TCP peer, normally traefik.
-- `forwarded_for`: the `X-Forwarded-For` header as received.
-- `client_group`: the client as rate limiting counts it, an IPv4 address as a
-  /32 or an IPv6 group.
-- `asn`, `as_name` and `country`: the client's, as looked up. Each is empty
-  when:
-    - lookups are off;
-    - the client is not looked up;
-    - the source cannot place the client;
-    - GeoJS had not answered by the time the request went on.
-- `content_type` and `content_length`: the request's own.
-- `request_headers`: the headers listed in `SWWAF_LOG_REQUEST_HEADERS`, by name
-  in lower case.
-- `has_authorization` and `has_cookie`: true when the request had those headers.
-  Their values are never logged.
-- `websocket`: true when the app switched the connection to another protocol.
-
-## Response detail
-
-- `upstream_status`: what the app answered. It differs from `status` when
-  `smallwebwaf` answered itself.
-- `response_content_type`, `cache_control` and `location`: the answer's headers.
-- `aborted`: true when the client went away early.
-
-## Decision
-
-- `action`: what was done:
-    - `forward`: passed to the app;
-    - `denied`: refused for `SWWAF_DENY_NETS`, or for a reputation source with
-      the action `deny`;
-    - `banned`: refused under a ban, or for a `ban` rule, a trap path or a
-      CrowdSec decision, each of which bans the client;
-    - `country_denied`, `rate_limited`, `rule_blocked` and `waf_blocked`:
-      refused by that check;
-    - `too_large`: a size limit was passed, or a header limit in `servewaf`;
-    - `timed_out`: a time limit was passed;
-    - `upstream_error`: the app could not be reached, or its answer broke off;
-    - `admin`: answered at one of `smallwebwaf`'s own endpoints.
-- `would_action`: in `observe` mode, what `enforce` mode would have done with a
-  request it would have refused. `action` then names what was done, normally
-  `forward`.
-- `limit_percent` and `limit_percent_setting`: the client's percentage of the
-  rate limits and the setting that lowered it, when one did. `bytes_percent` and
-  `bytes_percent_setting` do the same for the byte limits.
-- `counts`: the client's totals as rate limiting counts them, this request
-  included. It is left out when rate limiting did not count the request. It
-  holds:
-    - `minute`, `hour` and `day`: requests;
-    - `minute_bytes`, `hour_bytes` and `day_bytes`: bytes.
-
-    A count can have a fraction (see "Counting method" in
-    [`SPEC.md`](../SPEC.md)).
-
-- `limit_hit`: the limit broken:
-    - `minute`, `hour` or `day` for a rate limit;
-    - `minute_bytes`, `hour_bytes` or `day_bytes` for a byte limit;
-    - `error_burst`.
-
-    A request whose bytes broke a limit was passed on whole, so its `action`
-    stays `forward`.
-
-- `rule_ids`: the rule file rules that matched, in order, up to the one that
-  refused.
-- `waf_score` and `waf_rule_ids`: the Core Rule Set's score and the rules that
-  matched, for a request it inspected.
-- `reputation`: the sources the client is on, in this order:
-    - blocklist URLs;
-    - the CrowdSec decision list's URL;
-    - DNS blocklist zones;
-    - `abuseipdb`.
-- `offence`: `limit`, for a request that broke a limit.
-- `ban_expires`: when the client's ban ends, for a request that made one or was
-  refused under one: a time, or `permanent`.
-
-## Timings
-
-All in milliseconds:
-
-- `duration_total`: from the request's headers being read to its log line;
-- `duration_checks`: to the end of the checks, before forwarding;
-- `duration_waf`: the part of that the Core Rule Set took;
-- `duration_upstream_connect`: from the hand-over to the app until there was a
-  connection;
-- `duration_upstream_first_byte`: until the first byte of the answer;
-- `duration_upstream_total`: until the end of the answer.
+The fields of the JSON objects `rproxy` and `servewaf` write about each request.
+"Request log" and "The log" in [`SPEC.md`](../SPEC.md) say when a line is
+written and how the log is sent to a syslog server. A field that does not apply
+to a request is left out.
 
 ## `servewaf`'s lines
 
@@ -138,50 +23,180 @@ These questions write no line:
   [`SPEC.md`](../SPEC.md));
 - a question whose body stopped arriving, which gets no answer.
 
-### The `decision` line
+A `report` line:
 
-It has the fields above, with these meanings where they differ:
+```
+{"type":"request","servewaf_line":"report","time":"2026-10-03T12:00:00.123Z","instance":"fsn1/servewaf","client_ip":"203.0.113.9","method":"GET","scheme":"https","host":"app.example","path":"/","query":"","protocol":"HTTP/1.1","status":200,"request_bytes":0,"response_bytes":5120,"referer":"","user_agent":"curl/8.9.1","request_id":"7Q2NHZ4KJ3VXW5YB6R3MEFTD2A","peer_ip":"172.18.0.2","forwarded_for":"203.0.113.9","client_group":"203.0.113.9/32","asn":"AS64496","as_name":"Example Net","country":"DE","request_headers":{"accept":"*/*"},"action":"forward","counts":{"minute":1,"hour":12,"day":40,"minute_bytes":5120,"hour_bytes":61440,"day_bytes":204800},"waf_score":0,"duration_total":3.217,"duration_checks":0.041,"duration_waf":0.029,"duration_upstream_total":3.104}
+```
 
-- `client_ip`: `X-Smallwebwaf-Client`.
-- `peer_ip`: `X-Smallwebwaf-Peer`.
+### Every line
+
+Every one of these lines has:
+
+- `type`: `request` (the process's own messages have `process`);
+- the standard web log fields;
+- `request_id`, `peer_ip` and `client_group`;
+- `asn`, `as_name` and `country`;
+- `action` and `duration_total`.
+
+### Standard web log fields
+
+- `time`: when `servewaf` had read the question's body, RFC 3339 with
+  milliseconds, in UTC. The `report` line gives the same time as the `decision`
+  line.
+- `instance`: `SWWAF_INSTANCE_NAME`.
+- `client_ip`: the visitor's address, as `rproxy` worked it out.
+- `method`, `path` and `query`: the visitor's request.
+- `scheme`: how the visitor reached `rproxy` or the trusted proxy in front of
+  it.
 - `host`: the site the visitor asked for.
 - `protocol`: the question's own, `HTTP/1.1`.
-- `content_length`: `X-Smallwebwaf-Content-Length`.
-- `request_id`: the question's `X-Request-ID`.
-- `status`: what `servewaf` answered: `200` for `allow`, the status of `deny`,
-  or `0` for `close`, as the visitor is then sent nothing.
-- `request_bytes`: how much of the question's body the Core Rule Set read.
-- `response_bytes`: the body of `servewaf`'s answer.
-- `action`: `forward` for `allow`, and `admin` for the `404` for a path under
-  `/_smallwebwaf/`.
+- `status`:
+    - on the `decision` line, what `servewaf` answered: `200` for `allow`, the
+      status of `deny`, or `0` for `close`, as the visitor is then sent nothing;
+    - on the `report` line, what the visitor got, `0` if nothing.
+- `request_bytes`:
+    - on the `decision` line, how much of the question's body the Core Rule Set
+      read;
+    - on the `report` line, the bytes of the visitor's body that `rproxy` read,
+      with what a WebSocket carried from the visitor.
+- `response_bytes`:
+    - on the `decision` line, the body of `servewaf`'s answer;
+    - on the `report` line, the bytes of the answer's body, with what a
+      WebSocket carried from the app.
+- `referer` and `user_agent`.
+
+### Request detail
+
+- `request_id`: the id `rproxy` made for the request when it arrived.
+- `peer_ip`: the address of `rproxy`'s TCP peer, normally traefik.
+- `forwarded_for`: the `X-Forwarded-For` header the visitor's request came with.
+- `client_group`: the client as rate limiting counts it, an IPv4 address as a
+  /32 or an IPv6 group.
+- `asn`, `as_name` and `country`: the client's, as looked up. Each is empty
+  when:
+    - lookups are off;
+    - the client is not looked up;
+    - the source cannot place the client;
+    - GeoJS had not answered by the time `servewaf` answered.
+- `content_type`: the visitor's `Content-Type`.
+- `content_length`: the body length the visitor announced.
+- `request_headers`: the headers listed in `SWWAF_LOG_REQUEST_HEADERS`, by name
+  in lower case.
+- `has_authorization` and `has_cookie`: true when the request had those headers.
+  Their values are never logged.
+
+### Response detail
+
+- `response_content_type`: the type of `servewaf`'s own answer.
 - `aborted`: true when `rproxy` went away before the answer.
-- `duration_total`: from `servewaf` having read the question's body to the line.
-- `time`: when `servewaf` had read the question's body.
 
-The line leaves out `upstream_status`, `websocket` and the
-`duration_upstream_...` fields, since `servewaf` passes nothing to the app.
+### Decision
 
-The bytes of an allowed request are counted when its report comes. So `counts`
-holds the client's bytes without this request's.
+- `action`: what was done:
+    - `forward`: answered `allow`, so that `rproxy` passes it to the app;
+    - `denied`: refused for `SWWAF_DENY_NETS`, or for a reputation source with
+      the action `deny`;
+    - `banned`: refused under a ban, or for a `ban` rule, a trap path or a
+      CrowdSec decision, each of which bans the client;
+    - `country_denied`, `rate_limited`, `rule_blocked` and `waf_blocked`:
+      refused by that check;
+    - `too_large`: over a header limit;
+    - `admin`: answered at one of `servewaf`'s own endpoints, or `404` for a
+      path under `/_smallwebwaf/`.
+- `would_action`: in `observe` mode, what `enforce` mode would have done with a
+  request it would have refused. `action` then names what was done, normally
+  `forward`.
+- `heuristic`: the heuristic that refused the request, in `observe` mode too. It
+  is left out when none did.
+- `heuristic_figures`: an object of the figures that heuristic acted on. Each
+  heuristic and its figures:
+    - `deny_nets`: `netblock`, the entry of `SWWAF_DENY_NETS` the client is in;
+    - `active_ban`: `netblock`, the ban's netblock, and `ban_expires`;
+    - `countries`: `country`, and `setting`, the country list that refused it;
+    - `blocklists`: `lists`, the blocklist URLs that list the client;
+    - `crowdsec`: `scenario`, the decision's scenario, and `expires`, when the
+      decision ends;
+    - `dnsbl`: `zones`, the DNS blocklist zones that list the client, their keys
+      masked;
+    - `abuseipdb`: `score`, and `min_score`, `SWWAF_ABUSEIPDB_MIN_SCORE`;
+    - `rate_limits`: `window`, `count` and `limit`;
+    - `trap_paths`: `path`, the trap path asked for;
+    - `rule_files`: `rule_id` and `rule_action`, of the rule that refused it;
+    - `header_limits`: `fields`, `fields_limit`, `cookies` and `cookies_limit`;
+    - `core_rule_set`: `score`, and `threshold`, `SWWAF_WAF_ANOMALY_THRESHOLD`;
+    - `refusal_limit`: `window`, `count` and `limit`, of the error burst;
+    - `byte_limits`: `window`, `count` and `limit`, the count in bytes.
+- `after_answer_heuristic`: the heuristic that banned the client after
+  `servewaf` answered the request, in `observe` mode too: `refusal_limit` or
+  `byte_limits`.
+- `after_answer_heuristic_figures`: an object of the figures that heuristic
+  acted on, as listed above.
 
-### The `report` line
+    `byte_limits` bans when the report comes, so only the `report` line names
+    it.
 
-It has every field of the `decision` line, and `time` stays as the `decision`
-line gives it. These fields say what the report says:
+- `limit_percent` and `limit_percent_setting`: the client's percentage of the
+  rate limits and the setting that lowered it, when one did. `bytes_percent` and
+  `bytes_percent_setting` do the same for the byte limits.
+- `counts`: the client's totals as rate limiting counts them, this request
+  included. It is left out when rate limiting did not count the request. It
+  holds:
+    - `minute`, `hour` and `day`: requests;
+    - `minute_bytes`, `hour_bytes` and `day_bytes`: bytes.
 
-- `status`: what the visitor got, `0` if nothing;
-- `request_bytes` and `response_bytes`: the body bytes each way, with what a
-  WebSocket carried each way;
-- `duration_total`: from the request's headers being read by `rproxy` to the end
-  of the answer;
-- `duration_upstream_total`: from the hand-over to the app to the end of the
-  answer, for an allowed request.
+    A count can have a fraction (see "Counting method" in
+    [`SPEC.md`](../SPEC.md)). The bytes of an allowed request are counted when
+    its report comes. So on the `decision` line, the bytes are without this
+    request's.
 
-For an allowed request, the report's counting also changes these fields:
+- `limit_hit`: the limit broken:
+    - `minute`, `hour` or `day` for a rate limit;
+    - `minute_bytes`, `hour_bytes` or `day_bytes` for a byte limit;
+    - `error_burst`.
 
-- `counts`: the byte totals now include this request's;
-- `limit_hit`, `offence` and `ban_expires`: set when the report's bytes broke a
-  byte limit.
+    A request whose bytes broke a limit was passed on whole, so its `action`
+    stays `forward`. Only its `report` line gives that limit.
+
+- `rule_ids`: the rule file rules that matched, in order, up to the one that
+  refused.
+- `waf_score` and `waf_rule_ids`: the Core Rule Set's score and the rules that
+  matched, for a request it inspected.
+- `reputation`: the sources the client is on, in this order:
+    - blocklist URLs;
+    - the CrowdSec decision list's URL;
+    - DNS blocklist zones;
+    - `abuseipdb`.
+- `offence`: `limit`, for a request that broke a limit.
+- `ban_expires`: when the client's ban ends, for a request that made one or was
+  refused under one: a time, or `permanent`.
+
+### Timings
+
+All in milliseconds:
+
+- `duration_total`:
+    - on the `decision` line, from `servewaf` having read the question's body to
+      the line;
+    - on the `report` line, from `rproxy` having read the request's headers to
+      the end of the answer.
+- `duration_checks`: to the end of the checks;
+- `duration_waf`: the part of that the Core Rule Set took;
+- `duration_upstream_total`: on the `report` line of an allowed request, from
+  the hand-over to the app to the end of the answer.
+
+### Requests to its own endpoints
+
+The line of a request to `servewaf`'s own endpoints has these fields, with these
+meanings where they differ:
+
+- `client_ip` and `peer_ip`: the request's TCP peer.
+- `request_id`: a new random one of 26 letters and digits.
+- `scheme`: `http`.
+- `time`: when the request's headers had been read.
+- `request_bytes`: the bytes read of a ban to add, and otherwise `0`.
+- `action`: `admin`.
+- `duration_total`: from the request's headers being read to the line.
 
 ## `rproxy`'s line
 

docs/rules.md

@@ -54,14 +54,19 @@ empty-agent      user_agent  log     ^$
 
 ## A file of your own
 
-An app's `Dockerfile` adds rules of its own in a file named to sort after the
-default, such as `50-gitea.rules`:
+`servewaf` reads the rule files in its own container. Rules of your own go in a
+file named to sort after the default, such as `50-gitea.rules`:
 
 ```
 # 50-gitea.rules: WordPress probes, which gitea never serves
 wp-probe         path        ban     (?i)^/(wp-login\.php|xmlrpc\.php|wp-admin/)
 ```
 
+A `Dockerfile` built on the `smallwebwaf` image, for `servewaf` to run from,
+adds it:
+
 ```dockerfile
 COPY 50-gitea.rules /etc/smallwebwaf/rules.d/50-gitea.rules
 ```
+
+Or mount it there. A `path` rule applies on every site behind that `servewaf`.

docs/settings.md

@@ -4,6 +4,10 @@ Every setting, its default and the values it takes, in the groups of "Settings"
 in [`SPEC.md`](../SPEC.md). That section gives the conventions, the settings
 that take `off`, the `_FILE` form, and what each group does and why.
 
+The settings that start with `SWWAF_` are `servewaf`'s. Those that start with
+`SWRP_` are `rproxy`'s, and are under "`rproxy`" below. `SMALLWEBWAF_COMMAND`
+chooses between the two (see "The image's command" below).
+
 ## Forms of values
 
 - A duration is Go's syntax, with `d` for days: `90s`, `15m`, `24h`, `7d`. Zero
@@ -24,26 +28,22 @@ that take `off`, the `_FILE` form, and what each group does and why.
 
 ## Core
 
-- `SWWAF_UPSTREAM_URL` (default `http://127.0.0.1:8081`): the app. An `http` or
-  `https` URL with a host and an optional port, and nothing more.
-- `SWWAF_LISTEN_ADDR` (default `:8080`): where `smallwebwaf` listens: `:` and a
+- `SWWAF_LISTEN_ADDR` (default `:8080`): where `servewaf` listens: `:` and a
   port, such as `:9000`. Leave the host out (see "Ports" in
   [`SPEC.md`](../SPEC.md)).
 - `SWWAF_INSTANCE_NAME` (default: the container's host name): the `instance`
-  name in every log line, alert and metric, such as `fsn1app1/gitea`. Valid
-  UTF-8. No control character while `SWWAF_ALERT_NTFY_URL` is set. 1 to 48
-  printable ASCII characters without a space while `SWWAF_LOG_REMOTE_URL` is set
-  and `SWWAF_LOG_REMOTE_APP_NAME` is not.
+  name in each line `servewaf` logs, and in each alert and metric, such as
+  `fsn1/servewaf`. Valid UTF-8. No control character while
+  `SWWAF_ALERT_NTFY_URL` is set. 1 to 48 printable ASCII characters without a
+  space while `SWWAF_LOG_REMOTE_URL` is set and `SWWAF_LOG_REMOTE_APP_NAME` is
+  not.
 - `SWWAF_MODE` (default `enforce`): `enforce` or `observe`.
-- `SWWAF_TRUSTED_PROXIES` (default `10.0.0.0/8,172.16.0.0/12,192.168.0.0/16`):
-  the netblocks whose `X-Forwarded-For` is believed. Set but empty, it trusts
-  nothing.
 - `SWWAF_IPV6_GROUP_PREFIX` (default `64`): the prefix length of an IPv6
   client's group, from 32 to 128.
 - `SWWAF_MAX_TRACKED_CLIENTS` (default `20000`): the most clients kept, a whole
   number above zero.
-- `SWWAF_MAX_BANS` (default `5000`): how many of its own bans `smallwebwaf`
-  keeps, a whole number above zero.
+- `SWWAF_MAX_BANS` (default `5000`): how many of its own bans `servewaf` keeps,
+  a whole number above zero.
 
 ## Tokens
 
@@ -63,7 +63,7 @@ that take `off`, the `_FILE` form, and what each group does and why.
 
 ## Logging
 
-- `SWWAF_LOG_LEVEL` (default `info`): the least severe of `smallwebwaf`'s own
+- `SWWAF_LOG_LEVEL` (default `info`): the least severe of `servewaf`'s own
   messages that are written: `debug`, `info`, `warn` or `error`.
 - `SWWAF_LOG_REQUEST_HEADERS` (default
   `accept,accept-language,accept-encoding,content-type,origin,range`): the
@@ -99,19 +99,22 @@ that take `off`, the `_FILE` form, and what each group does and why.
 
 ## Request rate limits, per client
 
-- `SWWAF_RATE_LIMIT_PER_MINUTE` (default `500`, about 8 a second): the most
-  requests a client may make in a minute. A count or `off`. The default catches,
-  within seconds, a client firing requests as fast as it can. It leaves room for
-  a fleet of about 20 agents at its busiest, about 120 requests a minute. It
-  also leaves room for a few quick first visits to gitea with an empty cache,
-  about 40 files each.
-- `SWWAF_RATE_LIMIT_PER_HOUR` (default `20000`, about 5.5 a second): the most
-  requests a client may make in an hour. A count or `off`. The default leaves
-  room for an automation fleet at work. It catches a client that keeps up more
-  than about 5.5 a second for an hour.
-- `SWWAF_RATE_LIMIT_PER_DAY` (default `300000`, about 3.5 a second): the most
-  requests a client may make in a day. A count or `off`. The default catches a
-  scraper that keeps up 4 a second around the clock.
+- `SWWAF_RATE_LIMIT_PER_MINUTE` (default `120`, 2 a second): the most requests a
+  client may make in a minute. A count or `off`. The default leaves room for a
+  person opening two gitea pages at once with an empty cache, up to 60 files
+  each.
+- `SWWAF_RATE_LIMIT_PER_HOUR` (default `1500`): the most requests a client may
+  make in an hour. A count or `off`. It is the main limit against scrapers. A
+  person reading code in gitea for an hour, a page every 20 seconds, makes
+  about 900. A scraper making one request every 2 seconds makes 1,800 an hour,
+  more than the limit.
+- `SWWAF_RATE_LIMIT_PER_DAY` (default `6000`): the most requests a client may
+  make in a day. A count or `off`. The default is four hours at the hour limit.
+  A scraper making one request every 10 seconds makes 8,640 a day, more than the
+  limit.
+- An Actions runner asks gitea for work all day and can pass the limits. Put the
+  runners' addresses in `SWWAF_RATE_LIMIT_EXEMPT_NETS`. Do the same for a
+  network where many people share one address, such as an office.
 - Counting cannot catch a client that stays under all three limits (see "Request
   rate limits, per client" in [`SPEC.md`](../SPEC.md)).
 - `SWWAF_RATE_LIMIT_EXEMPT_PATHS` (default empty): path prefixes exempt from
@@ -119,33 +122,12 @@ that take `off`, the `_FILE` form, and what each group does and why.
 
 ## Byte limits, per client
 
-- `SWWAF_BYTES_LIMIT_PER_MINUTE` (default `4G`), `SWWAF_BYTES_LIMIT_PER_HOUR`
-  (default `20G`) and `SWWAF_BYTES_LIMIT_PER_DAY` (default `200G`): the most
+- `SWWAF_BYTES_LIMIT_PER_MINUTE` (default `off`), `SWWAF_BYTES_LIMIT_PER_HOUR`
+  (default `50G`) and `SWWAF_BYTES_LIMIT_PER_DAY` (default `100G`): the most
   bytes counted for a client in each window. A size or `off`.
 - `SWWAF_BYTES_COUNT` (default `both`): which body bytes the byte limits count:
   `response`, `request` or `both`.
 
-## Size and time limits
-
-- `SWWAF_CLIENT_REQUEST_TIMEOUT` (default `60s`): how long a client may take to
-  send its request line and headers, and then, from the end of the headers, its
-  body. A duration or `off`.
-- `SWWAF_CLIENT_REQUEST_HEADER_MAX_BYTES` (default `32K`): the largest request
-  line and headers. A size over `4K`; never `off`.
-- `SWWAF_CLIENT_IDLE_TIMEOUT` (default `120s`): how long a kept-open connection
-  may wait for its next request before it is closed. A duration or `off`.
-- `SWWAF_CLIENT_RESPONSE_TIMEOUT` (default `30m`): how long the answer may take
-  to reach the client, from the end of the request to the last byte. A duration
-  or `off`.
-- `SWWAF_UPSTREAM_REQUEST_TIMEOUT` (default `60s`): how long connecting to the
-  app and sending it the whole request may take. A duration or `off`.
-- `SWWAF_UPSTREAM_RESPONSE_TIMEOUT` (default `30m`): how long the app may take
-  to send its whole answer. A duration or `off`.
-- `SWWAF_REQUEST_MAX_BYTES` (default `100M`): the largest request body. A size
-  or `off`.
-- `SWWAF_RESPONSE_MAX_BYTES` (default `1G`): the largest response body. A size
-  or `off`.
-
 ## Lookup of AS number and country
 
 - `SWWAF_LOOKUP_SOURCE` (default `geojs`): `geojs`, `file` or `off`. `off` stops
@@ -160,8 +142,9 @@ that take `off`, the `_FILE` form, and what each group does and why.
 - `SWWAF_LOOKUP_TIMEOUT` (default `800ms`): how long a request waits for its
   client's first answer from GeoJS, and how long a request to GeoJS may take. A
   duration; never `off`.
-- `SWWAF_ADD_LOOKUP_HEADERS` (default `false`): `true` passes the app the
-  client's AS number in `X-Client-ASN` and its country in `X-Client-Country`.
+- `SWWAF_ADD_LOOKUP_HEADERS` (default `false`): `true` has `rproxy` pass the app
+  the client's AS number in `X-Client-ASN` and its country in
+  `X-Client-Country`.
 
 ## Country lists
 
@@ -206,7 +189,9 @@ that take `off`, the `_FILE` form, and what each group does and why.
 - `SWWAF_WAF_EXEMPT_PATHS` (default empty): path prefixes the Core Rule Set does
   not inspect.
 - `SWWAF_WAF_BODY_LIMIT` (default `off`): `off`, or how much of a request body
-  the Core Rule Set reads, a size of at most `1G`.
+  the Core Rule Set reads, a size of at most `64K`. A question carries no more
+  of a body than 64 KiB, and the Core Rule Set reads at most 64 KiB less one
+  byte of it, whatever the value (see "The answer" in [`SPEC.md`](../SPEC.md)).
 - `SWWAF_ERROR_BURST_THRESHOLD` (default `30`): the most refusals of one client
   in a minute (see "Attack detection" in `SPEC.md`). A count or `off`.
 
@@ -327,6 +312,7 @@ Then mount its directory into the container read-only, and name the file:
 ```sh
 docker run \
     -v /srv/app/tokens:/etc/smallwebwaf/tokens:ro \
+    -e SMALLWEBWAF_COMMAND=servewaf \
     -e SWWAF_METRICS_TOKEN_FILE=/etc/smallwebwaf/tokens/metrics \
     ...
 ```
@@ -349,22 +335,7 @@ A few limits are fixed rather than settings:
 - `rproxy` reads at most 1 MiB of the body of `servewaf`'s answer, and answers
   `502` to a longer one.
 
-## `servewaf`
-
-`smallwebwaf servewaf` uses every `SWWAF_` setting but these, which it ignores:
-
-- `SWWAF_UPSTREAM_URL` and `SWWAF_TRUSTED_PROXIES`;
-- the five timeouts under "Size and time limits";
-- `SWWAF_CLIENT_REQUEST_HEADER_MAX_BYTES`, `SWWAF_REQUEST_MAX_BYTES` and
-  `SWWAF_RESPONSE_MAX_BYTES`.
-
-An invalid value of one of these still stops the start, and the line of settings
-at start still shows them.
-
-`SWWAF_ADD_LOOKUP_HEADERS` puts the headers on the answer to `rproxy`, not on a
-request to an app. `SWWAF_WAF_BODY_LIMIT` has an effect up to 64 KiB less one
-byte, whatever its value. A question carries no more of a body than 64 KiB (see
-"`servewaf`" in [`SPEC.md`](../SPEC.md)).
+## `servewaf`'s answer and `rproxy`'s wait
 
 `SWWAF_LOOKUP_TIMEOUT` is the longest a question waits on an outside source.
 Keep it well under `rproxy`'s `SWRP_TIMEOUT_MS`, as the default is. No question
@@ -374,10 +345,10 @@ asked in the background (see "Answering in time" under "`servewaf`" in
 
 ## `rproxy`
 
-`smallwebwaf rproxy` reads the settings below and no others, and nothing else
-reads them. They are read once at start, and an invalid value stops the start.
-None can be given as a file, since `rproxy` never touches disk. "`rproxy`" in
-[`SPEC.md`](../SPEC.md) says what they do.
+`smallwebwaf rproxy` reads the settings below and no others. They are read once
+at start, and an invalid value stops the start. None can be given as a file,
+since `rproxy` never touches disk. "`rproxy`" in [`SPEC.md`](../SPEC.md) says
+what they do.
 
 A time here is a whole number of milliseconds above zero, such as `2000`.
 
@@ -406,4 +377,29 @@ A time here is a whole number of milliseconds above zero, such as `2000`.
   `https` URL with a host and an optional port, and nothing more.
 - `SWRP_TRUSTED_PROXIES` (default `10.0.0.0/8,172.16.0.0/12,192.168.0.0/16`):
   the netblocks whose `X-Forwarded-For` is believed. Set but empty, it trusts
-  nothing.
+  nothing. A client outside these netblocks cannot claim another address. Where
+  other containers reach `rproxy` directly, or visitors on a private network
+  reach traefik, they can name another address in the header. Narrowing the
+  setting to traefik's own network closes that gap.
+
+## The image's command
+
+`SMALLWEBWAF_COMMAND` (default `rproxy`) chooses what the image runs and what
+its health check checks: `rproxy` or `servewaf` (see "Deployment" in
+[`SPEC.md`](../SPEC.md)). It cannot be given as a file.
+
+## Where earlier settings went
+
+Nothing reads these names any more:
+
+- `SWWAF_UPSTREAM_URL` is `SWRP_UPSTREAM_URL`.
+- `SWWAF_TRUSTED_PROXIES` is `SWRP_TRUSTED_PROXIES`.
+- `SWWAF_REQUEST_MAX_BYTES` is `SWRP_MAX_REQUEST_SIZE`.
+- `SWWAF_RESPONSE_MAX_BYTES` is `SWRP_MAX_RESPONSE_SIZE`.
+- `SWWAF_CLIENT_REQUEST_TIMEOUT` and `SWWAF_UPSTREAM_REQUEST_TIMEOUT` are
+  `SWRP_MAX_REQUEST_TIME_MS`, in milliseconds.
+- `SWWAF_CLIENT_RESPONSE_TIMEOUT` and `SWWAF_UPSTREAM_RESPONSE_TIMEOUT` are
+  `SWRP_MAX_RESPONSE_TIME_MS`, in milliseconds.
+- `SWWAF_CLIENT_IDLE_TIMEOUT` and `SWWAF_CLIENT_REQUEST_HEADER_MAX_BYTES` have
+  no setting. `rproxy` closes a kept-open connection idle for 120 seconds, and
+  takes a request line and headers of at most 32 KiB.

docs/state-files.md

@@ -7,7 +7,7 @@ Each has a top-level `version` of 1.
 ## `bans.json`
 
 Active and past bans: every ban an admin made, and up to `SWWAF_MAX_BANS` of
-those `smallwebwaf` made. Per entry:
+those `servewaf` made. Per entry:
 
 - `netblock`, `start` and `expires` (`null` for a permanent ban);
 - `cause`: `attack`, `limit`, `admin` or `crowdsec`;
@@ -63,8 +63,8 @@ since it was first seen:
 - total requests, and how many were forwarded and how many refused;
 - bytes in each direction;
 - responses by status class;
-- offences by kind: `limit`, `attack`, `rule_blocked`, `waf_blocked` and
-  `token_refused`.
+- offences by kind: `limit`, `attack`, `rule_blocked` and `waf_blocked`. A file
+  may also hold `token_refused`, which is kept, and which nothing adds to.
 
 ## `lookups.json`
 

internal/config/config.go

@@ -1,9 +1,10 @@
 // Package config reads smallwebwaf's settings, and is the one place they are
-// read. Every setting is an environment variable. The settings of
-// `smallwebwaf` and `smallwebwaf servewaf` start with SWWAF_, every one of them
-// has a default, and most can be given as a file instead. Those of `smallwebwaf
-// rproxy` start with SWRP_. Each of them but SWRP_WAF_BACKEND has a default, and
-// none can be given as a file, since rproxy never touches disk.
+// read. Every setting is an environment variable. The settings of `smallwebwaf
+// servewaf` start with SWWAF_, every one of them has a default, and most can be
+// given as a file instead. Those of `smallwebwaf rproxy` start with SWRP_. Each
+// of them but SWRP_WAF_BACKEND has a default, and none can be given as a file,
+// since rproxy never touches disk. SMALLWEBWAF_COMMAND chooses which of the two
+// the image runs.
 package config
 
 import (
@@ -30,13 +31,11 @@ import (
 	"sneak.berlin/go/smallwebwaf/internal/remotelog"
 )
 
-// Config is smallwebwaf's settings. A timeout, size or rate limit of zero
-// is off.
+// Config is the settings of `smallwebwaf servewaf`. A time or size limit of
+// zero is off.
 type Config struct {
-	// ListenAddr is where smallwebwaf listens (SWWAF_LISTEN_ADDR).
+	// ListenAddr is where servewaf listens (SWWAF_LISTEN_ADDR).
 	ListenAddr string
-	// UpstreamURL is the app (SWWAF_UPSTREAM_URL).
-	UpstreamURL *url.URL
 	// InstanceName is the name every log line and alert gives as instance,
 	// and every metric carries as its label instance (SWWAF_INSTANCE_NAME),
 	// by default the host's name, which docker sets to the first 12
@@ -45,42 +44,14 @@ type Config struct {
 	// Observe is true in observe mode, when SWWAF_MODE is observe rather
 	// than enforce: a request that SWWAF_DENY_NETS, a ban, the country
 	// lists, a rate limit, a rule or the Core Rule Set would refuse is
-	// passed to the app instead, and no ban is made.
+	// allowed instead, and no ban is made.
 	Observe bool
-	// TrustedProxies are the netblocks whose X-Forwarded-For is
-	// believed (SWWAF_TRUSTED_PROXIES).
-	TrustedProxies []netip.Prefix
 	// IPv6GroupPrefix is the length of the IPv6 netblock that is one client
 	// (SWWAF_IPV6_GROUP_PREFIX), from 32 to 128.
 	IPv6GroupPrefix int
 	// MaxTrackedClients is the most clients the table of clients holds, in
 	// memory and in clients.json (SWWAF_MAX_TRACKED_CLIENTS).
 	MaxTrackedClients int
-	// ClientRequestTimeout bounds reading the whole request from the
-	// client (SWWAF_CLIENT_REQUEST_TIMEOUT).
-	ClientRequestTimeout time.Duration
-	// ClientRequestHeaderMaxBytes is the largest request line and headers
-	// a client may send (SWWAF_CLIENT_REQUEST_HEADER_MAX_BYTES). It is
-	// never off, and always more than 4K.
-	ClientRequestHeaderMaxBytes int64
-	// ClientIdleTimeout bounds how long a kept-open client connection
-	// may wait for its next request (SWWAF_CLIENT_IDLE_TIMEOUT).
-	ClientIdleTimeout time.Duration
-	// ClientResponseTimeout bounds writing the whole response to the
-	// client (SWWAF_CLIENT_RESPONSE_TIMEOUT).
-	ClientResponseTimeout time.Duration
-	// UpstreamRequestTimeout bounds connecting to the app and writing
-	// the whole request to it (SWWAF_UPSTREAM_REQUEST_TIMEOUT).
-	UpstreamRequestTimeout time.Duration
-	// UpstreamResponseTimeout bounds reading the whole response from
-	// the app (SWWAF_UPSTREAM_RESPONSE_TIMEOUT).
-	UpstreamResponseTimeout time.Duration
-	// RequestMaxBytes is the largest request body
-	// (SWWAF_REQUEST_MAX_BYTES).
-	RequestMaxBytes int64
-	// ResponseMaxBytes is the largest response body
-	// (SWWAF_RESPONSE_MAX_BYTES).
-	ResponseMaxBytes int64
 	// AllowNets are the netblocks whose clients skip every check
 	// (SWWAF_ALLOW_NETS). RateLimitExemptNets are those whose clients the
 	// rate limits neither count nor refuse (SWWAF_RATE_LIMIT_EXEMPT_NETS).
@@ -260,9 +231,8 @@ type Config struct {
 	// attack (SWWAF_TRAP_PATHS), each starting with / and without a ?.
 	TrapPaths []string
 	// ErrorBurstThreshold is the most requests of a client within a minute
-	// that smallwebwaf may refuse after a rule file or Core Rule Set match
-	// or for a missing or wrong token; one more breaks a limit
-	// (SWWAF_ERROR_BURST_THRESHOLD). 0 is off.
+	// that servewaf may refuse after a rule file or Core Rule Set match; one
+	// more breaks a limit (SWWAF_ERROR_BURST_THRESHOLD). 0 is off.
 	ErrorBurstThreshold int64
 	// LogRemoteURL is where every line on stdout is also sent
 	// (SWWAF_LOG_REMOTE_URL), nil while it is unset and nothing is sent.
@@ -365,8 +335,8 @@ const (
 	// masked is what the log shows for a token that is set, and in place of
 	// a secret in another setting.
 	masked = "********"
-	// defaultListenAddr and defaultUpstreamURL are the defaults of
-	// SWWAF_LISTEN_ADDR and SWWAF_UPSTREAM_URL.
+	// defaultListenAddr is the default of SWWAF_LISTEN_ADDR and
+	// SWRP_LISTEN_ADDR, and defaultUpstreamURL that of SWRP_UPSTREAM_URL.
 	defaultListenAddr  = ":8080"
 	defaultUpstreamURL = "http://127.0.0.1:8081"
 )
@@ -394,13 +364,14 @@ var (
 	errHeaderTakenOut = errors.New(
 		"is taken out of every request by Go's HTTP server, so it can never " +
 			"be logged")
-	errOnBothLists          = errors.New("is in SWWAF_DENIED_COUNTRIES too")
-	errNotLookupSource      = errors.New("is not geojs, file or off")
-	errNeedsLookups         = errors.New("it needs each client looked up")
-	errNeedsDBPath          = errors.New("it names the file to look clients up in")
-	errDBPathUnused         = errors.New("only file reads it")
-	errNotOver4K            = errors.New("is not a size of more than 4K, such as 32K")
-	errOver1G               = errors.New("is more than 1G, the most Coraza reads")
+	errOnBothLists     = errors.New("is in SWWAF_DENIED_COUNTRIES too")
+	errNotLookupSource = errors.New("is not geojs, file or off")
+	errNeedsLookups    = errors.New("it needs each client looked up")
+	errNeedsDBPath     = errors.New("it names the file to look clients up in")
+	errDBPathUnused    = errors.New("only file reads it")
+	errOver64K         = errors.New(
+		"is more than 64K, the most servewaf gets of a body")
+	errNotCommand           = errors.New("is not rproxy or servewaf")
 	errNotDurationAboveZero = errors.New(
 		"is not a duration above zero, such as 1h or 7d")
 	errNotNumberAboveZero = errors.New(
@@ -489,38 +460,27 @@ var (
 func FromEnvironment(lookupEnv func(string) (string, bool)) (*Config, error) {
 	env := &environment{lookupEnv: lookupEnv}
 	cfg := &Config{
-		ListenAddr:           env.address("SWWAF_LISTEN_ADDR", defaultListenAddr),
-		UpstreamURL:          env.appURL("SWWAF_UPSTREAM_URL", defaultUpstreamURL),
+		ListenAddr:           env.address("SWWAF_LISTEN_ADDR"),
 		InstanceName:         env.instanceName(),
 		Observe:              env.observe("SWWAF_MODE", "enforce"),
-		TrustedProxies:       env.netblocks("SWWAF_TRUSTED_PROXIES", privateRanges),
 		IPv6GroupPrefix:      env.ipv6GroupPrefix("SWWAF_IPV6_GROUP_PREFIX", "64"),
 		MaxTrackedClients:    env.numberNotOff("SWWAF_MAX_TRACKED_CLIENTS", "20000"),
-		ClientRequestTimeout: env.duration("SWWAF_CLIENT_REQUEST_TIMEOUT", "60s"),
-		ClientRequestHeaderMaxBytes: env.headerSize(
-			"SWWAF_CLIENT_REQUEST_HEADER_MAX_BYTES", "32K"),
-		ClientIdleTimeout:       env.duration("SWWAF_CLIENT_IDLE_TIMEOUT", "120s"),
-		ClientResponseTimeout:   env.duration("SWWAF_CLIENT_RESPONSE_TIMEOUT", "30m"),
-		UpstreamRequestTimeout:  env.duration("SWWAF_UPSTREAM_REQUEST_TIMEOUT", "60s"),
-		UpstreamResponseTimeout: env.duration("SWWAF_UPSTREAM_RESPONSE_TIMEOUT", "30m"),
-		RequestMaxBytes:         env.size("SWWAF_REQUEST_MAX_BYTES", "100M"),
-		ResponseMaxBytes:        env.size("SWWAF_RESPONSE_MAX_BYTES", "1G"),
-		AllowNets:               env.netblocks("SWWAF_ALLOW_NETS", ""),
-		RateLimitExemptNets:     env.netblocks("SWWAF_RATE_LIMIT_EXEMPT_NETS", ""),
-		DenyNets:                env.netblocks("SWWAF_DENY_NETS", ""),
-		RateLimitPerMinute:      env.count("SWWAF_RATE_LIMIT_PER_MINUTE", "500"),
-		RateLimitPerHour:        env.count("SWWAF_RATE_LIMIT_PER_HOUR", "20000"),
-		RateLimitPerDay:         env.count("SWWAF_RATE_LIMIT_PER_DAY", "300000"),
-		RateLimitExemptPaths:    env.pathPrefixes("SWWAF_RATE_LIMIT_EXEMPT_PATHS", ""),
-		BytesLimitPerMinute:     env.size("SWWAF_BYTES_LIMIT_PER_MINUTE", "4G"),
-		BytesLimitPerHour:       env.size("SWWAF_BYTES_LIMIT_PER_HOUR", "20G"),
-		BytesLimitPerDay:        env.size("SWWAF_BYTES_LIMIT_PER_DAY", "200G"),
-		BytesCount:              env.bytesCount("SWWAF_BYTES_COUNT", "both"),
-		LookupSource:            env.lookupSource("SWWAF_LOOKUP_SOURCE", "geojs"),
-		LookupDBPath:            env.value("SWWAF_LOOKUP_DB_PATH", ""),
-		LookupTimeout:           env.durationNotOff("SWWAF_LOOKUP_TIMEOUT", "800ms"),
-		AddLookupHeaders:        env.boolean("SWWAF_ADD_LOOKUP_HEADERS", "false"),
-		DeniedCountries:         env.countries("SWWAF_DENIED_COUNTRIES", ""),
+		AllowNets:            env.netblocks("SWWAF_ALLOW_NETS", ""),
+		RateLimitExemptNets:  env.netblocks("SWWAF_RATE_LIMIT_EXEMPT_NETS", ""),
+		DenyNets:             env.netblocks("SWWAF_DENY_NETS", ""),
+		RateLimitPerMinute:   env.count("SWWAF_RATE_LIMIT_PER_MINUTE", "120"),
+		RateLimitPerHour:     env.count("SWWAF_RATE_LIMIT_PER_HOUR", "1500"),
+		RateLimitPerDay:      env.count("SWWAF_RATE_LIMIT_PER_DAY", "6000"),
+		RateLimitExemptPaths: env.pathPrefixes("SWWAF_RATE_LIMIT_EXEMPT_PATHS", ""),
+		BytesLimitPerMinute:  env.size("SWWAF_BYTES_LIMIT_PER_MINUTE", "off"),
+		BytesLimitPerHour:    env.size("SWWAF_BYTES_LIMIT_PER_HOUR", "50G"),
+		BytesLimitPerDay:     env.size("SWWAF_BYTES_LIMIT_PER_DAY", "100G"),
+		BytesCount:           env.bytesCount("SWWAF_BYTES_COUNT", "both"),
+		LookupSource:         env.lookupSource("SWWAF_LOOKUP_SOURCE", "geojs"),
+		LookupDBPath:         env.value("SWWAF_LOOKUP_DB_PATH", ""),
+		LookupTimeout:        env.durationNotOff("SWWAF_LOOKUP_TIMEOUT", "800ms"),
+		AddLookupHeaders:     env.boolean("SWWAF_ADD_LOOKUP_HEADERS", "false"),
+		DeniedCountries:      env.countries("SWWAF_DENIED_COUNTRIES", ""),
 		ExclusivelyAllowedCountries: env.countries(
 			"SWWAF_EXCLUSIVELY_ALLOWED_COUNTRIES", ""),
 		ASNLimitPercent:      env.percents("SWWAF_ASN_LIMIT_PERCENT", ParseASN),
@@ -612,22 +572,30 @@ func FromEnvironment(lookupEnv func(string) (string, bool)) (*Config, error) {
 	return cfg, nil
 }
 
-// ListenAddrAndUpstreamURL reads only SWWAF_LISTEN_ADDR and
-// SWWAF_UPSTREAM_URL, either of which may be given as a file, as
-// FromEnvironment does. The health check needs no other setting, so it
-// reads no other, nor a file that another names.
-func ListenAddrAndUpstreamURL(
-	lookupEnv func(string) (string, bool),
-) (string, *url.URL, error) {
-	env := &environment{lookupEnv: lookupEnv}
-	listenAddr := env.address("SWWAF_LISTEN_ADDR", defaultListenAddr)
-	upstreamURL := env.appURL("SWWAF_UPSTREAM_URL", defaultUpstreamURL)
+// Command reads only SMALLWEBWAF_COMMAND, the command the image runs and its
+// health check checks: rproxy when it is unset or empty, or servewaf. It cannot
+// be given as a file. Any other value is an error that names the setting.
+func Command(lookupEnv func(string) (string, bool)) (string, error) {
+	command, _ := lookupEnv("SMALLWEBWAF_COMMAND")
 
-	if env.err != nil {
-		return "", nil, env.err
+	switch command {
+	case "", "rproxy":
+		return "rproxy", nil
+	case "servewaf":
+		return command, nil
+	default:
+		return "", fmt.Errorf("SMALLWEBWAF_COMMAND: %q %w", command, errNotCommand)
 	}
+}
 
-	return listenAddr, upstreamURL, nil
+// ServeWAFListenAddr reads only SWWAF_LISTEN_ADDR, which may be given as a
+// file, as FromEnvironment does. The health check in servewaf's container needs
+// no other setting, so it reads no other, nor a file that another names.
+func ServeWAFListenAddr(lookupEnv func(string) (string, bool)) (string, error) {
+	env := &environment{lookupEnv: lookupEnv}
+	listenAddr := env.address("SWWAF_LISTEN_ADDR")
+
+	return listenAddr, env.err
 }
 
 // InstanceName reads only SWWAF_INSTANCE_NAME, which may be given as a
@@ -709,9 +677,10 @@ func (e *environment) check(name string, err error) {
 	}
 }
 
-// address reads a setting that is an address to listen on.
-func (e *environment) address(name, defaultValue string) string {
-	address, err := parseListenAddr(e.value(name, defaultValue))
+// address reads a setting that is an address to listen on, by default
+// defaultListenAddr.
+func (e *environment) address(name string) string {
+	address, err := parseListenAddr(e.value(name, defaultListenAddr))
 	e.check(name, err)
 
 	return address
@@ -779,15 +748,6 @@ func (e *environment) wafBodyLimit(name, defaultValue string) int64 {
 	return limit
 }
 
-// headerSize reads the setting that is the largest request line and
-// headers.
-func (e *environment) headerSize(name, defaultValue string) int64 {
-	size, err := parseHeaderSize(e.value(name, defaultValue))
-	e.check(name, err)
-
-	return size
-}
-
 // count reads a setting that is a number of requests.
 func (e *environment) count(name, defaultValue string) int64 {
 	count, err := parseCount(e.value(name, defaultValue))
@@ -1434,30 +1394,17 @@ func parseSize(value string) (int64, error) {
 	return n * unit, nil
 }
 
-// parseHeaderSize reads the largest request line and headers: a size as
-// parseSize reads it, but more than 4K and never off. Go's server reads 4K
-// past the limit it is given before it refuses, so proxy.New gives it this
-// size less 4K, which must leave a limit.
-func parseHeaderSize(value string) (int64, error) {
-	size, err := parseSize(value)
-	if err != nil || size <= 4*kibibyte {
-		return 0, fmt.Errorf("%q %w", value, errNotOver4K)
-	}
-
-	return size, nil
-}
-
 // parseWAFBodyLimit reads the most of a request body the Core Rule Set
-// reads: a size as parseSize reads it, or off, but at most 1G, since
-// Coraza, which runs the Core Rule Set, refuses to load with more.
+// reads: a size as parseSize reads it, or off, but at most 64K, since servewaf
+// gets no more of a body than that.
 func parseWAFBodyLimit(value string) (int64, error) {
 	limit, err := parseSize(value)
 	if err != nil {
 		return 0, err
 	}
 
-	if limit > gibibyte {
-		return 0, fmt.Errorf("%q %w", value, errOver1G)
+	if limit > 64*kibibyte {
+		return 0, fmt.Errorf("%q %w", value, errOver64K)
 	}
 
 	return limit, nil

internal/config/config_test.go

@@ -23,98 +23,88 @@ import (
 
 // The settings, by name.
 const (
-	listenAddr              = "SWWAF_LISTEN_ADDR"
-	upstreamURL             = "SWWAF_UPSTREAM_URL"
-	mode                    = "SWWAF_MODE"
-	trustedProxies          = "SWWAF_TRUSTED_PROXIES"
-	ipv6GroupPrefix         = "SWWAF_IPV6_GROUP_PREFIX"
-	maxTrackedClients       = "SWWAF_MAX_TRACKED_CLIENTS"
-	clientRequestTimeout    = "SWWAF_CLIENT_REQUEST_TIMEOUT"
-	clientHeaderMaxBytes    = "SWWAF_CLIENT_REQUEST_HEADER_MAX_BYTES"
-	clientIdleTimeout       = "SWWAF_CLIENT_IDLE_TIMEOUT"
-	clientResponseTimeout   = "SWWAF_CLIENT_RESPONSE_TIMEOUT"
-	upstreamRequestTimeout  = "SWWAF_UPSTREAM_REQUEST_TIMEOUT"
-	upstreamResponseTimeout = "SWWAF_UPSTREAM_RESPONSE_TIMEOUT"
-	requestMaxBytes         = "SWWAF_REQUEST_MAX_BYTES"
-	responseMaxBytes        = "SWWAF_RESPONSE_MAX_BYTES"
-	allowNets               = "SWWAF_ALLOW_NETS"
-	rateLimitExemptNets     = "SWWAF_RATE_LIMIT_EXEMPT_NETS"
-	denyNets                = "SWWAF_DENY_NETS"
-	rateLimitPerMinute      = "SWWAF_RATE_LIMIT_PER_MINUTE"
-	rateLimitPerHour        = "SWWAF_RATE_LIMIT_PER_HOUR"
-	rateLimitPerDay         = "SWWAF_RATE_LIMIT_PER_DAY"
-	rateLimitExemptPaths    = "SWWAF_RATE_LIMIT_EXEMPT_PATHS"
-	bytesLimitPerMinute     = "SWWAF_BYTES_LIMIT_PER_MINUTE"
-	bytesLimitPerHour       = "SWWAF_BYTES_LIMIT_PER_HOUR"
-	bytesLimitPerDay        = "SWWAF_BYTES_LIMIT_PER_DAY"
-	bytesCount              = "SWWAF_BYTES_COUNT"
-	lookupSource            = "SWWAF_LOOKUP_SOURCE"
-	lookupDBPath            = "SWWAF_LOOKUP_DB_PATH"
-	lookupTimeout           = "SWWAF_LOOKUP_TIMEOUT"
-	addLookupHeaders        = "SWWAF_ADD_LOOKUP_HEADERS"
-	deniedCountries         = "SWWAF_DENIED_COUNTRIES"
-	allowedCountries        = "SWWAF_EXCLUSIVELY_ALLOWED_COUNTRIES"
-	asnLimitPercent         = "SWWAF_ASN_LIMIT_PERCENT"
-	countryLimitPercent     = "SWWAF_COUNTRY_LIMIT_PERCENT"
-	asnBytesPercent         = "SWWAF_ASN_BYTES_PERCENT"
-	countryBytesPercent     = "SWWAF_COUNTRY_BYTES_PERCENT"
-	unknownLimitPercent     = "SWWAF_UNKNOWN_LIMIT_PERCENT"
-	asnLimitPercentURL      = "SWWAF_ASN_LIMIT_PERCENT_URL"
-	blocklistURLs           = "SWWAF_BLOCKLIST_URLS"
-	blocklistRefresh        = "SWWAF_BLOCKLIST_REFRESH"
-	blocklistAction         = "SWWAF_BLOCKLIST_ACTION"
-	dnsblZones              = "SWWAF_DNSBL_ZONES"
-	dnsblResolver           = "SWWAF_DNSBL_RESOLVER"
-	abuseIPDBKey            = "SWWAF_ABUSEIPDB_KEY"
-	abuseIPDBMinScore       = "SWWAF_ABUSEIPDB_MIN_SCORE"
-	abuseIPDBDailyBudget    = "SWWAF_ABUSEIPDB_DAILY_BUDGET"
-	reputationAction        = "SWWAF_REPUTATION_ACTION"
-	reputationCacheTTL      = "SWWAF_REPUTATION_CACHE_TTL"
-	reputationTimeout       = "SWWAF_REPUTATION_TIMEOUT"
-	crowdSecURL             = "SWWAF_CROWDSEC_LAPI_URL"
-	crowdSecKey             = "SWWAF_CROWDSEC_LAPI_KEY"
-	banResponse             = "SWWAF_BAN_RESPONSE"
-	limitBanDuration        = "SWWAF_LIMIT_BAN_DURATION"
-	limitBanRepeatWindow    = "SWWAF_LIMIT_BAN_REPEAT_WINDOW"
-	maxBanDuration          = "SWWAF_MAX_BAN_DURATION"
-	attackBanDuration       = "SWWAF_ATTACK_BAN_DURATION"
-	maxBans                 = "SWWAF_MAX_BANS"
-	banScopeV4Prefix        = "SWWAF_BAN_SCOPE_V4_PREFIX"
-	stateDir                = "SWWAF_STATE_DIR"
-	stateWriteDelay         = "SWWAF_STATE_WRITE_DELAY"
-	stateCounterInterval    = "SWWAF_STATE_COUNTER_INTERVAL"
-	adminToken              = "SWWAF_ADMIN_TOKEN"   //nolint:gosec // the setting's name
-	metricsToken            = "SWWAF_METRICS_TOKEN" //nolint:gosec // the setting's name
-	metricsTopN             = "SWWAF_METRICS_TOP_N"
-	instanceName            = "SWWAF_INSTANCE_NAME"
-	logRequestHeaders       = "SWWAF_LOG_REQUEST_HEADERS"
-	logLevel                = "SWWAF_LOG_LEVEL"
-	rulesDir                = "SWWAF_RULES_DIR"
-	rulesEnabled            = "SWWAF_RULES_ENABLED"
-	wafMode                 = "SWWAF_WAF_MODE"
-	wafParanoiaLevel        = "SWWAF_WAF_PARANOIA_LEVEL"
-	wafAnomalyThreshold     = "SWWAF_WAF_ANOMALY_THRESHOLD"
-	wafDisabledRules        = "SWWAF_WAF_DISABLED_RULES"
-	wafExemptPaths          = "SWWAF_WAF_EXEMPT_PATHS"
-	wafBodyLimit            = "SWWAF_WAF_BODY_LIMIT"
-	trapPaths               = "SWWAF_TRAP_PATHS"
-	errorBurstThreshold     = "SWWAF_ERROR_BURST_THRESHOLD"
-	logRemoteURL            = "SWWAF_LOG_REMOTE_URL"
-	logRemoteTLSCAFile      = "SWWAF_LOG_REMOTE_TLS_CA_FILE"
-	logRemoteBuffer         = "SWWAF_LOG_REMOTE_BUFFER"
-	logRemoteFacility       = "SWWAF_LOG_REMOTE_FACILITY"
-	logRemoteAppName        = "SWWAF_LOG_REMOTE_APP_NAME"
-	alertWebhookURL         = "SWWAF_ALERT_WEBHOOK_URL"
-	alertWebhookHeaders     = "SWWAF_ALERT_WEBHOOK_HEADERS"
-	alertSlackWebhookURL    = "SWWAF_ALERT_SLACK_WEBHOOK_URL"
-	alertNtfyURL            = "SWWAF_ALERT_NTFY_URL"
-	alertNtfyToken          = "SWWAF_ALERT_NTFY_TOKEN" //nolint:gosec // the setting's name
-	alertEvents             = "SWWAF_ALERT_EVENTS"
-	alertCooldown           = "SWWAF_ALERT_COOLDOWN"
-	alertMaxPerHour         = "SWWAF_ALERT_MAX_PER_HOUR"
-	anomalyNetV4Prefix      = "SWWAF_ANOMALY_NET_V4_PREFIX"
-	anomalyNetV6Prefix      = "SWWAF_ANOMALY_NET_V6_PREFIX"
-	watchNets               = "SWWAF_WATCH_NETS"
+	listenAddr           = "SWWAF_LISTEN_ADDR"
+	mode                 = "SWWAF_MODE"
+	ipv6GroupPrefix      = "SWWAF_IPV6_GROUP_PREFIX"
+	maxTrackedClients    = "SWWAF_MAX_TRACKED_CLIENTS"
+	allowNets            = "SWWAF_ALLOW_NETS"
+	rateLimitExemptNets  = "SWWAF_RATE_LIMIT_EXEMPT_NETS"
+	denyNets             = "SWWAF_DENY_NETS"
+	rateLimitPerMinute   = "SWWAF_RATE_LIMIT_PER_MINUTE"
+	rateLimitPerHour     = "SWWAF_RATE_LIMIT_PER_HOUR"
+	rateLimitPerDay      = "SWWAF_RATE_LIMIT_PER_DAY"
+	rateLimitExemptPaths = "SWWAF_RATE_LIMIT_EXEMPT_PATHS"
+	bytesLimitPerMinute  = "SWWAF_BYTES_LIMIT_PER_MINUTE"
+	bytesLimitPerHour    = "SWWAF_BYTES_LIMIT_PER_HOUR"
+	bytesLimitPerDay     = "SWWAF_BYTES_LIMIT_PER_DAY"
+	bytesCount           = "SWWAF_BYTES_COUNT"
+	lookupSource         = "SWWAF_LOOKUP_SOURCE"
+	lookupDBPath         = "SWWAF_LOOKUP_DB_PATH"
+	lookupTimeout        = "SWWAF_LOOKUP_TIMEOUT"
+	addLookupHeaders     = "SWWAF_ADD_LOOKUP_HEADERS"
+	deniedCountries      = "SWWAF_DENIED_COUNTRIES"
+	allowedCountries     = "SWWAF_EXCLUSIVELY_ALLOWED_COUNTRIES"
+	asnLimitPercent      = "SWWAF_ASN_LIMIT_PERCENT"
+	countryLimitPercent  = "SWWAF_COUNTRY_LIMIT_PERCENT"
+	asnBytesPercent      = "SWWAF_ASN_BYTES_PERCENT"
+	countryBytesPercent  = "SWWAF_COUNTRY_BYTES_PERCENT"
+	unknownLimitPercent  = "SWWAF_UNKNOWN_LIMIT_PERCENT"
+	asnLimitPercentURL   = "SWWAF_ASN_LIMIT_PERCENT_URL"
+	blocklistURLs        = "SWWAF_BLOCKLIST_URLS"
+	blocklistRefresh     = "SWWAF_BLOCKLIST_REFRESH"
+	blocklistAction      = "SWWAF_BLOCKLIST_ACTION"
+	dnsblZones           = "SWWAF_DNSBL_ZONES"
+	dnsblResolver        = "SWWAF_DNSBL_RESOLVER"
+	abuseIPDBKey         = "SWWAF_ABUSEIPDB_KEY"
+	abuseIPDBMinScore    = "SWWAF_ABUSEIPDB_MIN_SCORE"
+	abuseIPDBDailyBudget = "SWWAF_ABUSEIPDB_DAILY_BUDGET"
+	reputationAction     = "SWWAF_REPUTATION_ACTION"
+	reputationCacheTTL   = "SWWAF_REPUTATION_CACHE_TTL"
+	reputationTimeout    = "SWWAF_REPUTATION_TIMEOUT"
+	crowdSecURL          = "SWWAF_CROWDSEC_LAPI_URL"
+	crowdSecKey          = "SWWAF_CROWDSEC_LAPI_KEY"
+	banResponse          = "SWWAF_BAN_RESPONSE"
+	limitBanDuration     = "SWWAF_LIMIT_BAN_DURATION"
+	limitBanRepeatWindow = "SWWAF_LIMIT_BAN_REPEAT_WINDOW"
+	maxBanDuration       = "SWWAF_MAX_BAN_DURATION"
+	attackBanDuration    = "SWWAF_ATTACK_BAN_DURATION"
+	maxBans              = "SWWAF_MAX_BANS"
+	banScopeV4Prefix     = "SWWAF_BAN_SCOPE_V4_PREFIX"
+	stateDir             = "SWWAF_STATE_DIR"
+	stateWriteDelay      = "SWWAF_STATE_WRITE_DELAY"
+	stateCounterInterval = "SWWAF_STATE_COUNTER_INTERVAL"
+	adminToken           = "SWWAF_ADMIN_TOKEN"   //nolint:gosec // the setting's name
+	metricsToken         = "SWWAF_METRICS_TOKEN" //nolint:gosec // the setting's name
+	metricsTopN          = "SWWAF_METRICS_TOP_N"
+	instanceName         = "SWWAF_INSTANCE_NAME"
+	logRequestHeaders    = "SWWAF_LOG_REQUEST_HEADERS"
+	logLevel             = "SWWAF_LOG_LEVEL"
+	rulesDir             = "SWWAF_RULES_DIR"
+	rulesEnabled         = "SWWAF_RULES_ENABLED"
+	wafMode              = "SWWAF_WAF_MODE"
+	wafParanoiaLevel     = "SWWAF_WAF_PARANOIA_LEVEL"
+	wafAnomalyThreshold  = "SWWAF_WAF_ANOMALY_THRESHOLD"
+	wafDisabledRules     = "SWWAF_WAF_DISABLED_RULES"
+	wafExemptPaths       = "SWWAF_WAF_EXEMPT_PATHS"
+	wafBodyLimit         = "SWWAF_WAF_BODY_LIMIT"
+	trapPaths            = "SWWAF_TRAP_PATHS"
+	errorBurstThreshold  = "SWWAF_ERROR_BURST_THRESHOLD"
+	logRemoteURL         = "SWWAF_LOG_REMOTE_URL"
+	logRemoteTLSCAFile   = "SWWAF_LOG_REMOTE_TLS_CA_FILE"
+	logRemoteBuffer      = "SWWAF_LOG_REMOTE_BUFFER"
+	logRemoteFacility    = "SWWAF_LOG_REMOTE_FACILITY"
+	logRemoteAppName     = "SWWAF_LOG_REMOTE_APP_NAME"
+	alertWebhookURL      = "SWWAF_ALERT_WEBHOOK_URL"
+	alertWebhookHeaders  = "SWWAF_ALERT_WEBHOOK_HEADERS"
+	alertSlackWebhookURL = "SWWAF_ALERT_SLACK_WEBHOOK_URL"
+	alertNtfyURL         = "SWWAF_ALERT_NTFY_URL"
+	alertNtfyToken       = "SWWAF_ALERT_NTFY_TOKEN" //nolint:gosec // the setting's name
+	alertEvents          = "SWWAF_ALERT_EVENTS"
+	alertCooldown        = "SWWAF_ALERT_COOLDOWN"
+	alertMaxPerHour      = "SWWAF_ALERT_MAX_PER_HOUR"
+	anomalyNetV4Prefix   = "SWWAF_ANOMALY_NET_V4_PREFIX"
+	anomalyNetV6Prefix   = "SWWAF_ANOMALY_NET_V6_PREFIX"
+	watchNets            = "SWWAF_WATCH_NETS"
 )
 
 // The anomaly thresholds: each of the prefixes below, which name a scope,
@@ -252,48 +242,34 @@ func TestDefaults(t *testing.T) {
 	cfg := fromEnvironment(t, environment{})
 
 	wantSettings(t, cfg, config.Config{
-		ListenAddr:                  ":8080",
-		Observe:                     false,
-		ClientRequestTimeout:        time.Minute,
-		ClientRequestHeaderMaxBytes: 32 << 10,
-		ClientIdleTimeout:           2 * time.Minute,
-		ClientResponseTimeout:       30 * time.Minute,
-		UpstreamRequestTimeout:      time.Minute,
-		UpstreamResponseTimeout:     30 * time.Minute,
-		RequestMaxBytes:             100 << 20,
-		ResponseMaxBytes:            1 << 30,
-		RateLimitPerMinute:          500,
-		RateLimitPerHour:            20000,
-		RateLimitPerDay:             300000,
-		BanResponse:                 403,
-		LimitBanDuration:            time.Hour,
-		LimitBanRepeatWindow:        24 * time.Hour,
-		MaxBanDuration:              7 * 24 * time.Hour,
-		AttackBanDuration:           7 * 24 * time.Hour,
-		MaxBans:                     5000,
-		BanScopeV4Prefix:            32,
-		StateDir:                    "/var/lib/smallwebwaf",
-		StateWriteDelay:             10 * time.Second,
-		StateCounterInterval:        15 * time.Minute,
-		MetricsToken:                "",
-		MetricsTopN:                 50,
-		RulesDir:                    "/etc/smallwebwaf/rules.d",
-		RulesEnabled:                true,
+		ListenAddr:           ":8080",
+		Observe:              false,
+		RateLimitPerMinute:   120,
+		RateLimitPerHour:     1500,
+		RateLimitPerDay:      6000,
+		BanResponse:          403,
+		LimitBanDuration:     time.Hour,
+		LimitBanRepeatWindow: 24 * time.Hour,
+		MaxBanDuration:       7 * 24 * time.Hour,
+		AttackBanDuration:    7 * 24 * time.Hour,
+		MaxBans:              5000,
+		BanScopeV4Prefix:     32,
+		StateDir:             "/var/lib/smallwebwaf",
+		StateWriteDelay:      10 * time.Second,
+		StateCounterInterval: 15 * time.Minute,
+		MetricsToken:         "",
+		MetricsTopN:          50,
+		RulesDir:             "/etc/smallwebwaf/rules.d",
+		RulesEnabled:         true,
 	})
 	wantLookupSettings(t, cfg, config.Config{
 		LookupSource: defaultLookupSource, LookupTimeout: 800 * time.Millisecond,
 	})
 	wantByteLimitSettings(t, cfg, config.Config{
-		BytesLimitPerMinute: 4 << 30, BytesLimitPerHour: 20 << 30,
-		BytesLimitPerDay: 200 << 30, BytesCount: "both",
+		BytesLimitPerMinute: 0, BytesLimitPerHour: 50 << 30,
+		BytesLimitPerDay: 100 << 30, BytesCount: "both",
 	})
 
-	if cfg.UpstreamURL.String() != "http://127.0.0.1:8081" {
-		t.Errorf("%s is %s", upstreamURL, cfg.UpstreamURL)
-	}
-
-	wantNetblocks(t, cfg.TrustedProxies,
-		"10.0.0.0/8", "172.16.0.0/12", "192.168.0.0/16")
 	wantNetblocks(t, cfg.AllowNets)
 	wantNetblocks(t, cfg.RateLimitExemptNets)
 	wantNetblocks(t, cfg.DenyNets)
@@ -322,12 +298,17 @@ func TestNoSingleRequestBreaksAByteLimitAtTheDefaults(t *testing.T) {
 
 	cfg := fromEnvironment(t, environment{})
 
+	rproxy, err := rproxyConfig(map[string]string{wafBackend: backendURL})
+	if err != nil {
+		t.Fatalf("settings: %v", err)
+	}
+
 	// The largest request body and the largest response, both counted.
-	largest := cfg.RequestMaxBytes + cfg.ResponseMaxBytes
+	largest := rproxy.MaxRequestSize + rproxy.MaxResponseSize
 	for _, limit := range []int64{
 		cfg.BytesLimitPerMinute, cfg.BytesLimitPerHour, cfg.BytesLimitPerDay,
 	} {
-		if largest > limit {
+		if limit != 0 && largest > limit { // 0 is off
 			t.Errorf("a request of %d bytes breaks the byte limit of %d", largest, limit)
 		}
 	}
@@ -337,77 +318,54 @@ func TestValuesAsSet(t *testing.T) {
 	t.Parallel()
 
 	cfg := fromEnvironment(t, environment{
-		listenAddr:              "127.0.0.1:9000",
-		upstreamURL:             "https://app.internal:8443/",
-		mode:                    "observe",
-		trustedProxies:          " 192.0.2.1, 10.1.2.3/8 ,2001:db8::/32",
-		clientRequestTimeout:    "90s",
-		clientHeaderMaxBytes:    "8K",
-		clientIdleTimeout:       "5m",
-		clientResponseTimeout:   "7d",
-		upstreamRequestTimeout:  "1h30m",
-		upstreamResponseTimeout: off,
-		requestMaxBytes:         "512K",
-		responseMaxBytes:        "1234",
-		allowNets:               "192.0.2.7",
-		rateLimitExemptNets:     "2001:db8::/48, 10.9.8.7",
-		denyNets:                "198.51.100.0/24",
-		rateLimitPerMinute:      "60",
-		rateLimitPerHour:        "600",
-		rateLimitPerDay:         "6000",
-		deniedCountries:         "cn, RU,kp,Xk",
-		allowedCountries:        "de",
-		banResponse:             "429",
-		limitBanDuration:        "15m",
-		limitBanRepeatWindow:    "2d",
-		maxBanDuration:          "30d",
-		attackBanDuration:       "1d",
-		maxBans:                 "100",
-		banScopeV4Prefix:        "24",
-		stateDir:                "/srv/waf-state",
-		stateWriteDelay:         "500ms",
-		stateCounterInterval:    "1h",
-		metricsToken:            token,
-		metricsTopN:             "10",
-		rulesDir:                "/srv/waf-rules",
-		rulesEnabled:            "false",
+		listenAddr:           "127.0.0.1:9000",
+		mode:                 "observe",
+		allowNets:            "192.0.2.7",
+		rateLimitExemptNets:  "2001:db8::/48, 10.9.8.7",
+		denyNets:             "198.51.100.0/24",
+		rateLimitPerMinute:   "60",
+		rateLimitPerHour:     "600",
+		rateLimitPerDay:      "6000",
+		deniedCountries:      "cn, RU,kp,Xk",
+		allowedCountries:     "de",
+		banResponse:          "429",
+		limitBanDuration:     "15m",
+		limitBanRepeatWindow: "2d",
+		maxBanDuration:       "30d",
+		attackBanDuration:    "1d",
+		maxBans:              "100",
+		banScopeV4Prefix:     "24",
+		stateDir:             "/srv/waf-state",
+		stateWriteDelay:      "500ms",
+		stateCounterInterval: "1h",
+		metricsToken:         token,
+		metricsTopN:          "10",
+		rulesDir:             "/srv/waf-rules",
+		rulesEnabled:         "false",
 	})
 
 	wantSettings(t, cfg, config.Config{
-		ListenAddr:                  "127.0.0.1:9000",
-		Observe:                     true,
-		ClientRequestTimeout:        90 * time.Second,
-		ClientRequestHeaderMaxBytes: 8 << 10,
-		ClientIdleTimeout:           5 * time.Minute,
-		ClientResponseTimeout:       7 * 24 * time.Hour,
-		UpstreamRequestTimeout:      90 * time.Minute,
-		UpstreamResponseTimeout:     0,
-		RequestMaxBytes:             512 << 10,
-		ResponseMaxBytes:            1234,
-		RateLimitPerMinute:          60,
-		RateLimitPerHour:            600,
-		RateLimitPerDay:             6000,
-		BanResponse:                 429,
-		LimitBanDuration:            15 * time.Minute,
-		LimitBanRepeatWindow:        48 * time.Hour,
-		MaxBanDuration:              30 * 24 * time.Hour,
-		AttackBanDuration:           24 * time.Hour,
-		MaxBans:                     100,
-		BanScopeV4Prefix:            24,
-		StateDir:                    "/srv/waf-state",
-		StateWriteDelay:             500 * time.Millisecond,
-		StateCounterInterval:        time.Hour,
-		MetricsToken:                token,
-		MetricsTopN:                 10,
-		RulesDir:                    "/srv/waf-rules",
-		RulesEnabled:                false,
+		ListenAddr:           "127.0.0.1:9000",
+		Observe:              true,
+		RateLimitPerMinute:   60,
+		RateLimitPerHour:     600,
+		RateLimitPerDay:      6000,
+		BanResponse:          429,
+		LimitBanDuration:     15 * time.Minute,
+		LimitBanRepeatWindow: 48 * time.Hour,
+		MaxBanDuration:       30 * 24 * time.Hour,
+		AttackBanDuration:    24 * time.Hour,
+		MaxBans:              100,
+		BanScopeV4Prefix:     24,
+		StateDir:             "/srv/waf-state",
+		StateWriteDelay:      500 * time.Millisecond,
+		StateCounterInterval: time.Hour,
+		MetricsToken:         token,
+		MetricsTopN:          10,
+		RulesDir:             "/srv/waf-rules",
+		RulesEnabled:         false,
 	})
 
-	if cfg.UpstreamURL.String() != "https://app.internal:8443/" {
-		t.Errorf("%s is %s", upstreamURL, cfg.UpstreamURL)
-	}
-
-	wantNetblocks(t, cfg.TrustedProxies, "192.0.2.1/32", "10.0.0.0/8", "2001:db8::/32")
 	wantNetblocks(t, cfg.AllowNets, "192.0.2.7/32")
 	wantNetblocks(t, cfg.RateLimitExemptNets, "2001:db8::/48", "10.9.8.7/32")
 	wantNetblocks(t, cfg.DenyNets, "198.51.100.0/24")
@@ -581,13 +539,13 @@ func TestCoreRuleSetSettings(t *testing.T) {
 			environment{
 				wafMode: config.WAFModeDetect, wafParanoiaLevel: "4", wafAnomalyThreshold: "10",
 				wafDisabledRules: "942100, 920350", wafExemptPaths: "/api/, /static/",
-				wafBodyLimit: "128K",
+				wafBodyLimit: "32K",
 			},
 			config.Config{
 				WAFMode: config.WAFModeDetect, WAFParanoiaLevel: 4, WAFAnomalyThreshold: 10,
 				WAFDisabledRules: []int{942100, 920350},
 				WAFExemptPaths:   []string{"/api/", "/static/"},
-				WAFBodyLimit:     128 << 10,
+				WAFBodyLimit:     32 << 10,
 			},
 		},
 		{
@@ -615,12 +573,12 @@ func TestCoreRuleSetSettings(t *testing.T) {
 	}
 }
 
-func TestWAFBodyLimitOf1G(t *testing.T) {
+func TestWAFBodyLimitOf64K(t *testing.T) {
 	t.Parallel()
 
-	cfg := fromEnvironment(t, environment{wafBodyLimit: "1G"})
-	if cfg.WAFBodyLimit != 1<<30 {
-		t.Errorf("1G read as %d", cfg.WAFBodyLimit)
+	cfg := fromEnvironment(t, environment{wafBodyLimit: "64K"})
+	if cfg.WAFBodyLimit != 64<<10 {
+		t.Errorf("64K read as %d", cfg.WAFBodyLimit)
 	}
 }
 
@@ -669,10 +627,10 @@ func TestInvalidCoreRuleSetSettingStopsTheStart(t *testing.T) {
 			wafBodyLimit, "128KB",
 			`"128KB" is not a size such as 512K, 100M or 5G, or off`,
 		},
-		{wafBodyLimit, "2G", `"2G" is more than 1G, the most Coraza reads`},
+		{wafBodyLimit, "65K", `"65K" is more than 64K, the most servewaf gets of a body`},
 		{
-			wafBodyLimit, "1073741825",
-			`"1073741825" is more than 1G, the most Coraza reads`,
+			wafBodyLimit, "65537",
+			`"65537" is more than 64K, the most servewaf gets of a body`,
 		},
 	} {
 		t.Run(tc.name+"="+tc.value, func(t *testing.T) {
@@ -1967,45 +1925,15 @@ func TestSizesAndOff(t *testing.T) {
 	t.Parallel()
 
 	cfg := fromEnvironment(t, environment{
-		requestMaxBytes:      "3G",
-		responseMaxBytes:     off,
-		clientRequestTimeout: off,
-		clientIdleTimeout:    off,
+		bytesLimitPerMinute: "3G",
+		bytesLimitPerHour:   off,
+		alertCooldown:       off,
 	})
 
-	if cfg.RequestMaxBytes != 3<<30 || cfg.ResponseMaxBytes != 0 ||
-		cfg.ClientRequestTimeout != 0 || cfg.ClientIdleTimeout != 0 {
-		t.Errorf("3G, off, off and off read as %d, %d, %s and %s",
-			cfg.RequestMaxBytes, cfg.ResponseMaxBytes, cfg.ClientRequestTimeout,
-			cfg.ClientIdleTimeout)
-	}
-}
-
-func TestRequestHeaderMaxBytesJustOver4K(t *testing.T) {
-	t.Parallel()
-
-	cfg := fromEnvironment(t, environment{clientHeaderMaxBytes: "4097"})
-	if cfg.ClientRequestHeaderMaxBytes != 4097 {
-		t.Errorf("4097 read as %d", cfg.ClientRequestHeaderMaxBytes)
-	}
-}
-
-func TestRequestHeaderMaxBytesRefusalNeverOffersOff(t *testing.T) {
-	t.Parallel()
-
-	for _, value := range []string{"32KB", "0", "4K", off} {
-		t.Run(value, func(t *testing.T) {
-			t.Parallel()
-
-			_, err := config.FromEnvironment(
-				environment{clientHeaderMaxBytes: value}.lookupEnv)
-
-			want := clientHeaderMaxBytes + `: "` + value +
-				`" is not a size of more than 4K, such as 32K`
-			if err == nil || err.Error() != want {
-				t.Errorf("error %v, want %s", err, want)
-			}
-		})
+	if cfg.BytesLimitPerMinute != 3<<30 || cfg.BytesLimitPerHour != 0 ||
+		cfg.AlertCooldown != 0 {
+		t.Errorf("3G, off and off read as %d, %d and %s",
+			cfg.BytesLimitPerMinute, cfg.BytesLimitPerHour, cfg.AlertCooldown)
 	}
 }
 
@@ -2034,34 +1962,12 @@ func TestBanResponseCloseIsZero(t *testing.T) {
 	}
 }
 
-func TestTrustedProxiesSetButEmptyTrustNothing(t *testing.T) {
-	t.Parallel()
-
-	cfg := fromEnvironment(t, environment{trustedProxies: ""})
-	if len(cfg.TrustedProxies) != 0 {
-		t.Errorf("trusted proxies %v, want none", cfg.TrustedProxies)
-	}
-}
-
 func TestInvalidValueStopsTheStart(t *testing.T) {
 	t.Parallel()
 
 	wantStartStopped(t, []struct{ name, value string }{
 		{listenAddr, "8080"}, {listenAddr, ":http"}, {listenAddr, ":65536"},
-		{upstreamURL, "127.0.0.1:8081"},
-		{upstreamURL, "ftp://127.0.0.1:8081"},
-		{upstreamURL, "http://"},
-		{upstreamURL, "http://:8081"},
-		{upstreamURL, "http://127.0.0.1:0"},
-		{upstreamURL, "http://127.0.0.1:99999"},
-		{upstreamURL, "http://127.0.0.1:8081/app"},
-		{upstreamURL, "http://127.0.0.1:8081/?a=1"},
-		{upstreamURL, "http://user:secret@127.0.0.1:8081"},
 		{mode, "Observe"}, {mode, "block"}, {mode, ""},
-		{trustedProxies, "10.0.0.0/33"},
-		{trustedProxies, "traefik"},
-		{trustedProxies, "10.0.0.0/8,,192.168.0.0/16"},
-		{trustedProxies, "fe80::1%eth0"},
 		{ipv6GroupPrefix, "31"}, {ipv6GroupPrefix, "129"}, {ipv6GroupPrefix, "/64"},
 		{ipv6GroupPrefix, off}, {ipv6GroupPrefix, ""},
 		{maxTrackedClients, "0"}, {maxTrackedClients, "-1"}, {maxTrackedClients, off},
@@ -2069,19 +1975,18 @@ func TestInvalidValueStopsTheStart(t *testing.T) {
 		{allowNets, "192.0.2.0/24,monitoring"},
 		{rateLimitExemptNets, "2001:db8::/129"},
 		{denyNets, "198.51.100.0/24,"},
-		{clientRequestTimeout, "60"}, {clientRequestTimeout, ""},
-		{clientIdleTimeout, "0s"},
-		{clientIdleTimeout, "2 minutes"},
-		{clientResponseTimeout, "1y"},
-		{upstreamRequestTimeout, "-1s"},
-		{upstreamResponseTimeout, "0s"},
-		{upstreamResponseTimeout, "1.5d"},
-		{requestMaxBytes, "100MB"},
-		{requestMaxBytes, "100m"},
-		{requestMaxBytes, "1.5M"},
-		{responseMaxBytes, "0"},
-		{responseMaxBytes, "-5"},
-		{responseMaxBytes, "99999999999G"},
+		{alertCooldown, "60"}, {alertCooldown, ""},
+		{alertCooldown, "0s"},
+		{alertCooldown, "2 minutes"},
+		{alertCooldown, "1y"},
+		{alertCooldown, "-1s"},
+		{alertCooldown, "1.5d"},
+		{bytesLimitPerMinute, "100MB"},
+		{bytesLimitPerMinute, "100m"},
+		{bytesLimitPerMinute, "1.5M"},
+		{bytesLimitPerHour, "0"},
+		{bytesLimitPerHour, "-5"},
+		{bytesLimitPerHour, "99999999999G"},
 		{rateLimitPerMinute, ""},
 		{rateLimitPerMinute, "1K"},
 		{rateLimitPerHour, "0"},
@@ -2246,10 +2151,10 @@ func TestSettingFromFileIsCheckedAsTheSettingItself(t *testing.T) {
 	t.Parallel()
 
 	_, err := config.FromEnvironment(environment{
-		requestMaxBytes + "_FILE": writeFile(t, "lots\n"),
+		bytesLimitPerMinute + "_FILE": writeFile(t, "lots\n"),
 	}.lookupEnv)
 
-	want := requestMaxBytes + `: "lots" is not a size such as 512K, 100M or 5G, or off`
+	want := bytesLimitPerMinute + `: "lots" is not a size such as 512K, 100M or 5G, or off`
 	if err == nil || err.Error() != want {
 		t.Errorf("error %v, want %s", err, want)
 	}
@@ -2354,99 +2259,89 @@ func writeFile(t *testing.T, contents string) string {
 func TestLogsEachSettingWithItsValue(t *testing.T) {
 	t.Parallel()
 
-	cfg := fromEnvironment(t, environment{clientRequestTimeout: "45s"})
+	cfg := fromEnvironment(t, environment{rateLimitPerMinute: "45"})
 	hostname, _ := os.Hostname()
 
 	want := map[string]string{
-		listenAddr:              ":8080",
-		upstreamURL:             "http://127.0.0.1:8081",
-		mode:                    "enforce",
-		trustedProxies:          "10.0.0.0/8,172.16.0.0/12,192.168.0.0/16",
-		ipv6GroupPrefix:         "64",
-		maxTrackedClients:       "20000",
-		clientRequestTimeout:    "45s",
-		clientHeaderMaxBytes:    "32K",
-		clientIdleTimeout:       "120s",
-		clientResponseTimeout:   "30m",
-		upstreamRequestTimeout:  "60s",
-		upstreamResponseTimeout: "30m",
-		requestMaxBytes:         "100M",
-		responseMaxBytes:        "1G",
-		allowNets:               "",
-		rateLimitExemptNets:     "",
-		denyNets:                "",
-		rateLimitPerMinute:      "500",
-		rateLimitPerHour:        "20000",
-		rateLimitPerDay:         "300000",
-		rateLimitExemptPaths:    "",
-		bytesLimitPerMinute:     "4G",
-		bytesLimitPerHour:       "20G",
-		bytesLimitPerDay:        "200G",
-		bytesCount:              "both",
-		lookupSource:            defaultLookupSource,
-		lookupDBPath:            "",
-		lookupTimeout:           "800ms",
-		addLookupHeaders:        "false",
-		deniedCountries:         "",
-		allowedCountries:        "",
-		asnLimitPercent:         "",
-		countryLimitPercent:     "",
-		asnBytesPercent:         "",
-		countryBytesPercent:     "",
-		unknownLimitPercent:     "100",
-		asnLimitPercentURL:      "",
-		blocklistURLs:           "",
-		blocklistRefresh:        "24h",
-		blocklistAction:         actionDeny,
-		dnsblZones:              "",
-		dnsblResolver:           "",
-		abuseIPDBKey:            "",
-		abuseIPDBMinScore:       "75",
-		abuseIPDBDailyBudget:    "900",
-		reputationAction:        "limit:25",
-		reputationCacheTTL:      defaultReputationCacheTTL,
-		reputationTimeout:       "2s",
-		crowdSecURL:             "",
-		crowdSecKey:             "",
-		banResponse:             "403",
-		limitBanDuration:        "1h",
-		limitBanRepeatWindow:    "24h",
-		maxBanDuration:          "7d",
-		attackBanDuration:       "7d",
-		maxBans:                 "5000",
-		banScopeV4Prefix:        "32",
-		stateDir:                "/var/lib/smallwebwaf",
-		stateWriteDelay:         "10s",
-		stateCounterInterval:    "15m",
-		adminToken:              "",
-		metricsToken:            "",
-		metricsTopN:             "50",
-		instanceName:            hostname,
-		logRequestHeaders:       defaultLogRequestHeaders,
-		logLevel:                "info",
-		rulesDir:                "/etc/smallwebwaf/rules.d",
-		rulesEnabled:            "true",
-		wafMode:                 config.WAFModeBlock,
-		wafParanoiaLevel:        "1",
-		wafAnomalyThreshold:     "5",
-		wafDisabledRules:        defaultWAFDisabledRules,
-		wafExemptPaths:          "",
-		wafBodyLimit:            off,
-		trapPaths:               "",
-		errorBurstThreshold:     "30",
-		logRemoteURL:            "",
-		logRemoteTLSCAFile:      "",
-		logRemoteBuffer:         "10000",
-		logRemoteFacility:       "local0",
-		logRemoteAppName:        hostname,
-		alertWebhookURL:         "",
-		alertWebhookHeaders:     "",
-		alertSlackWebhookURL:    "",
-		alertNtfyURL:            "",
-		alertNtfyToken:          "",
-		alertEvents:             defaultAlertEvents,
-		alertCooldown:           defaultAlertCooldown,
-		alertMaxPerHour:         "60",
+		listenAddr:           ":8080",
+		mode:                 "enforce",
+		ipv6GroupPrefix:      "64",
+		maxTrackedClients:    "20000",
+		allowNets:            "",
+		rateLimitExemptNets:  "",
+		denyNets:             "",
+		rateLimitPerMinute:   "45",
+		rateLimitPerHour:     "1500",
+		rateLimitPerDay:      "6000",
+		rateLimitExemptPaths: "",
+		bytesLimitPerMinute:  "off",
+		bytesLimitPerHour:    "50G",
+		bytesLimitPerDay:     "100G",
+		bytesCount:           "both",
+		lookupSource:         defaultLookupSource,
+		lookupDBPath:         "",
+		lookupTimeout:        "800ms",
+		addLookupHeaders:     "false",
+		deniedCountries:      "",
+		allowedCountries:     "",
+		asnLimitPercent:      "",
+		countryLimitPercent:  "",
+		asnBytesPercent:      "",
+		countryBytesPercent:  "",
+		unknownLimitPercent:  "100",
+		asnLimitPercentURL:   "",
+		blocklistURLs:        "",
+		blocklistRefresh:     "24h",
+		blocklistAction:      actionDeny,
+		dnsblZones:           "",
+		dnsblResolver:        "",
+		abuseIPDBKey:         "",
+		abuseIPDBMinScore:    "75",
+		abuseIPDBDailyBudget: "900",
+		reputationAction:     "limit:25",
+		reputationCacheTTL:   defaultReputationCacheTTL,
+		reputationTimeout:    "2s",
+		crowdSecURL:          "",
+		crowdSecKey:          "",
+		banResponse:          "403",
+		limitBanDuration:     "1h",
+		limitBanRepeatWindow: "24h",
+		maxBanDuration:       "7d",
+		attackBanDuration:    "7d",
+		maxBans:              "5000",
+		banScopeV4Prefix:     "32",
+		stateDir:             "/var/lib/smallwebwaf",
+		stateWriteDelay:      "10s",
+		stateCounterInterval: "15m",
+		adminToken:           "",
+		metricsToken:         "",
+		metricsTopN:          "50",
+		instanceName:         hostname,
+		logRequestHeaders:    defaultLogRequestHeaders,
+		logLevel:             "info",
+		rulesDir:             "/etc/smallwebwaf/rules.d",
+		rulesEnabled:         "true",
+		wafMode:              config.WAFModeBlock,
+		wafParanoiaLevel:     "1",
+		wafAnomalyThreshold:  "5",
+		wafDisabledRules:     defaultWAFDisabledRules,
+		wafExemptPaths:       "",
+		wafBodyLimit:         off,
+		trapPaths:            "",
+		errorBurstThreshold:  "30",
+		logRemoteURL:         "",
+		logRemoteTLSCAFile:   "",
+		logRemoteBuffer:      "10000",
+		logRemoteFacility:    "local0",
+		logRemoteAppName:     hostname,
+		alertWebhookURL:      "",
+		alertWebhookHeaders:  "",
+		alertSlackWebhookURL: "",
+		alertNtfyURL:         "",
+		alertNtfyToken:       "",
+		alertEvents:          defaultAlertEvents,
+		alertCooldown:        defaultAlertCooldown,
+		alertMaxPerHour:      "60",
 	}
 	maps.Copy(want, loggedAnomalyDefaults())
 
@@ -2481,14 +2376,6 @@ func wantSettings(t *testing.T, got *config.Config, want config.Config) {
 
 	if got.ListenAddr != want.ListenAddr ||
 		got.Observe != want.Observe ||
-		got.ClientRequestTimeout != want.ClientRequestTimeout ||
-		got.ClientRequestHeaderMaxBytes != want.ClientRequestHeaderMaxBytes ||
-		got.ClientIdleTimeout != want.ClientIdleTimeout ||
-		got.ClientResponseTimeout != want.ClientResponseTimeout ||
-		got.UpstreamRequestTimeout != want.UpstreamRequestTimeout ||
-		got.UpstreamResponseTimeout != want.UpstreamResponseTimeout ||
-		got.RequestMaxBytes != want.RequestMaxBytes ||
-		got.ResponseMaxBytes != want.ResponseMaxBytes ||
 		got.RateLimitPerMinute != want.RateLimitPerMinute ||
 		got.RateLimitPerHour != want.RateLimitPerHour ||
 		got.RateLimitPerDay != want.RateLimitPerDay {

internal/config/rproxy.go

@@ -64,15 +64,9 @@ var (
 // invalid is an error that names it. Since rproxy never touches disk, its
 // settings have no _FILE form.
 func RProxyFromEnvironment(lookupEnv func(string) (string, bool)) (*RProxy, error) {
-	env := &environment{lookupEnv: func(name string) (string, bool) {
-		if strings.HasSuffix(name, "_FILE") {
-			return "", false
-		}
-
-		return lookupEnv(name)
-	}}
+	env := &environment{lookupEnv: withoutFileForms(lookupEnv)}
 	cfg := &RProxy{
-		ListenAddr:         env.address("SWRP_LISTEN_ADDR", defaultListenAddr),
+		ListenAddr:         env.address("SWRP_LISTEN_ADDR"),
 		UpstreamURL:        env.appURL("SWRP_UPSTREAM_URL", defaultUpstreamURL),
 		TrustedProxies:     env.netblocks("SWRP_TRUSTED_PROXIES", privateRanges),
 		WAFBackend:         env.wafBackend("SWRP_WAF_BACKEND"),
@@ -93,6 +87,37 @@ func RProxyFromEnvironment(lookupEnv func(string) (string, bool)) (*RProxy, erro
 	return cfg, nil
 }
 
+// RProxyListenAddrAndUpstreamURL reads only SWRP_LISTEN_ADDR and
+// SWRP_UPSTREAM_URL. The health check in rproxy's container needs no other
+// setting, so it reads no other.
+func RProxyListenAddrAndUpstreamURL(
+	lookupEnv func(string) (string, bool),
+) (string, *url.URL, error) {
+	env := &environment{lookupEnv: withoutFileForms(lookupEnv)}
+	listenAddr := env.address("SWRP_LISTEN_ADDR")
+	upstreamURL := env.appURL("SWRP_UPSTREAM_URL", defaultUpstreamURL)
+
+	if env.err != nil {
+		return "", nil, env.err
+	}
+
+	return listenAddr, upstreamURL, nil
+}
+
+// withoutFileForms returns lookupEnv finding no setting named with _FILE, since
+// rproxy never touches disk.
+func withoutFileForms(
+	lookupEnv func(string) (string, bool),
+) func(string) (string, bool) {
+	return func(name string) (string, bool) {
+		if strings.HasSuffix(name, "_FILE") {
+			return "", false
+		}
+
+		return lookupEnv(name)
+	}
+}
+
 // LogValue makes an RProxy log as each setting's name with the value it was
 // given, or its default.
 func (c *RProxy) LogValue() slog.Value {

internal/config/rproxy_test.go

@@ -125,7 +125,19 @@ func TestRProxyInvalidSettingsAreRefused(t *testing.T) {
 		{rproxyDefault, "maybe"},
 		{rproxyListen, "8080"},
 		{rproxyUpstream, "app"},
+		{rproxyUpstream, "127.0.0.1:8081"},
+		{rproxyUpstream, "ftp://127.0.0.1:8081"},
+		{rproxyUpstream, "http://"},
+		{rproxyUpstream, "http://:8081"},
+		{rproxyUpstream, "http://127.0.0.1:0"},
+		{rproxyUpstream, "http://127.0.0.1:99999"},
+		{rproxyUpstream, "http://127.0.0.1:8081/app"},
+		{rproxyUpstream, "http://127.0.0.1:8081/?a=1"},
+		{rproxyUpstream, "http://user:secret@127.0.0.1:8081"},
 		{rproxyTrusted, "not a netblock"},
+		{rproxyTrusted, "10.0.0.0/33"},
+		{rproxyTrusted, "10.0.0.0/8,,192.168.0.0/16"},
+		{rproxyTrusted, "fe80::1%eth0"},
 		{rproxyMaxRequest, notASize},
 		{rproxyMaxResponse, notASize},
 		{rproxyRequestTime, "0"},
@@ -143,6 +155,19 @@ func TestRProxyInvalidSettingsAreRefused(t *testing.T) {
 	}
 }
 
+func TestRProxyTrustedProxiesSetButEmptyTrustNothing(t *testing.T) {
+	t.Parallel()
+
+	cfg, err := rproxyConfig(map[string]string{wafBackend: backendURL, rproxyTrusted: ""})
+	if err != nil {
+		t.Fatalf("settings: %v", err)
+	}
+
+	if len(cfg.TrustedProxies) != 0 {
+		t.Errorf("trusted proxies %v, want none", cfg.TrustedProxies)
+	}
+}
+
 func TestRProxyNeedsItsBackend(t *testing.T) {
 	t.Parallel()
 

internal/metrics/metrics.go

@@ -28,16 +28,15 @@ type Metrics struct {
 	registry prometheus.Registerer
 	handler  http.Handler
 
-	inFlight             prometheus.Gauge
-	requests             *prometheus.CounterVec
-	requestBytes         *prometheus.CounterVec
-	responseBytes        *prometheus.CounterVec
-	requestDuration      prometheus.Histogram
-	upstreamDuration     prometheus.Histogram
-	rateLimitHits        *prometheus.CounterVec
-	sizeAndTimeLimitHits *prometheus.CounterVec
-	offences             *prometheus.CounterVec
-	wafMatches           *prometheus.CounterVec
+	inFlight         prometheus.Gauge
+	requests         *prometheus.CounterVec
+	requestBytes     *prometheus.CounterVec
+	responseBytes    *prometheus.CounterVec
+	requestDuration  prometheus.Histogram
+	upstreamDuration prometheus.Histogram
+	rateLimitHits    *prometheus.CounterVec
+	offences         *prometheus.CounterVec
+	wafMatches       *prometheus.CounterVec
 	// ruleMatches are made by AddRules, and reputationHits by
 	// AddReputation.
 	ruleMatches    *prometheus.CounterVec
@@ -100,9 +99,6 @@ func New(topN int, instanceName string) *Metrics {
 			"Requests that broke a rate limit, a byte limit or the error burst, by "+
 				"its window and its kind, requests, bytes or refusals.",
 			[]string{"window", "kind"}),
-		sizeAndTimeLimitHits: counterVec("smallwebwaf_size_and_time_limit_hits_total",
-			"Requests that passed a size or time limit, by its setting.",
-			[]string{"limit"}),
 		offences: counterVec("smallwebwaf_offences_total",
 			"Offences, by kind.", []string{"kind"}),
 		wafMatches: counterVec("smallwebwaf_waf_matches_total",
@@ -143,7 +139,7 @@ func New(topN int, instanceName string) *Metrics {
 		collectors.NewProcessCollector(collectors.ProcessCollectorOpts{}),
 		m.inFlight, m.requests, m.requestBytes, m.responseBytes,
 		m.requestDuration, m.upstreamDuration,
-		m.rateLimitHits, m.sizeAndTimeLimitHits, m.offences, m.wafMatches,
+		m.rateLimitHits, m.offences, m.wafMatches,
 		m.countries, m.asns,
 		m.GeoJSRequests, m.GeoJSFailures, m.GeoJSUnanswered,
 		m.stateFileWrites, m.stateFileWriteFailures,
@@ -395,15 +391,11 @@ func (m *Metrics) RequestStarted() {
 	m.inFlight.Inc()
 }
 
-// RequestEnded counts a request that has ended, from its log line. limit
-// is the setting whose size or time limit the request passed, "" if none.
-// duration is how long the request took, and upstreamDuration how long it
-// took from when it was passed to the app, zero if it was not.
-func (m *Metrics) RequestEnded(
-	line *requestlog.Line, limit string, duration, upstreamDuration time.Duration,
-) {
+// RequestEnded counts a request that has ended without being passed to the app,
+// from its log line. duration is how long the request took.
+func (m *Metrics) RequestEnded(line *requestlog.Line, duration time.Duration) {
 	m.inFlight.Dec()
-	m.count(line, limit, duration, upstreamDuration)
+	m.count(line, duration, 0)
 }
 
 // RequestAllowed counts a question of rproxy's, answered allow, as no longer
@@ -412,12 +404,13 @@ func (m *Metrics) RequestAllowed() {
 	m.inFlight.Dec()
 }
 
-// RequestReported counts a request rproxy passed to the app, as RequestEnded
-// does, from what its report says, which line holds.
+// RequestReported counts a request rproxy passed to the app, from what its
+// report says, which line holds: duration is how long the request took, and
+// upstreamDuration how long it took from when it was passed to the app.
 func (m *Metrics) RequestReported(
 	line *requestlog.Line, duration, upstreamDuration time.Duration,
 ) {
-	m.count(line, "", duration, upstreamDuration)
+	m.count(line, duration, upstreamDuration)
 }
 
 // LimitHit counts a request that broke a rate limit, a byte limit or the
@@ -431,11 +424,10 @@ func (m *Metrics) LimitHit(hit ratelimit.Hit) {
 // them.
 func (m *Metrics) Offences(r ratelimit.Request) {
 	for kind, committed := range map[string]bool{
-		"limit":         r.BrokeLimit,
-		"attack":        r.Attack,
-		"rule_blocked":  r.RuleBlocked,
-		"waf_blocked":   r.WAFBlocked,
-		"token_refused": r.TokenRefused,
+		"limit":        r.BrokeLimit,
+		"attack":       r.Attack,
+		"rule_blocked": r.RuleBlocked,
+		"waf_blocked":  r.WAFBlocked,
 	} {
 		if committed {
 			m.offences.WithLabelValues(kind).Inc()
@@ -486,9 +478,10 @@ func (m *Metrics) StateFileEditSetAside(name string) {
 	m.stateFileEditsSetAside.WithLabelValues(name).Inc()
 }
 
-// count counts a request that has ended, as RequestEnded describes.
+// count counts a request that has ended, as RequestEnded and RequestReported
+// describe.
 func (m *Metrics) count(
-	line *requestlog.Line, limit string, duration, upstreamDuration time.Duration,
+	line *requestlog.Line, duration, upstreamDuration time.Duration,
 ) {
 	class := statusClass(line.Status)
 	m.requests.WithLabelValues(class, line.Action).Inc()
@@ -500,10 +493,6 @@ func (m *Metrics) count(
 		m.upstreamDuration.Observe(upstreamDuration.Seconds())
 	}
 
-	if limit != "" {
-		m.sizeAndTimeLimitHits.WithLabelValues(limit).Inc()
-	}
-
 	if line.Country != "" {
 		m.countries.add(line.Country, line)
 	}

internal/proxy/bodies.go

@@ -1,239 +0,0 @@
-package proxy
-
-import (
-	"bufio"
-	"errors"
-	"io"
-	"net"
-	"net/http"
-	"sync/atomic"
-
-	"sneak.berlin/go/smallwebwaf/internal/requestlog"
-)
-
-// errResponseTooLarge ends an app's response body that is longer than
-// SWWAF_RESPONSE_MAX_BYTES.
-var errResponseTooLarge = errors.New(
-	"the response body is over SWWAF_RESPONSE_MAX_BYTES")
-
-// requestBody is the client's request body on its way to the app. The
-// transport reads it on a goroutine of its own.
-type requestBody struct {
-	// body is the client's body, ending in an *http.MaxBytesError past
-	// SWWAF_REQUEST_MAX_BYTES.
-	body io.ReadCloser
-	rq   *request
-	// readByCoreRuleSet is what the Core Rule Set read of the body before
-	// the request went to the app, and Read gives first.
-	readByCoreRuleSet []byte
-	// waiting is true while a Read waits for the client to send more.
-	waiting atomic.Bool
-	// received is true once the client has sent the whole body.
-	received atomic.Bool
-	// bytes is how much of the body has been read.
-	bytes atomic.Int64
-}
-
-// Read reads from the client's body, after what the Core Rule Set read of
-// it, which has been counted already.
-func (b *requestBody) Read(p []byte) (int, error) {
-	if len(b.readByCoreRuleSet) > 0 {
-		n := copy(p, b.readByCoreRuleSet)
-		b.readByCoreRuleSet = b.readByCoreRuleSet[n:]
-
-		return n, nil
-	}
-
-	b.waiting.Store(true)
-	n, err := b.body.Read(p)
-	b.waiting.Store(false)
-	b.bytes.Add(int64(n))
-
-	var tooLarge *http.MaxBytesError
-
-	switch {
-	case errors.Is(err, io.EOF):
-		b.received.Store(true)
-		b.rq.bodyReceived()
-	case errors.As(err, &tooLarge):
-		b.rq.refuse(refusal{
-			status: http.StatusRequestEntityTooLarge,
-			action: requestlog.ActionTooLarge,
-			limit:  "SWWAF_REQUEST_MAX_BYTES",
-		})
-	}
-
-	return n, err
-}
-
-// Close closes the client's body.
-func (b *requestBody) Close() error {
-	return b.body.Close()
-}
-
-// responseBody is the app's response body on its way to the client.
-type responseBody struct {
-	// body is the app's body, ending in an *http.MaxBytesError past
-	// SWWAF_RESPONSE_MAX_BYTES.
-	body io.ReadCloser
-	rq   *request
-}
-
-// Read reads from the app's body.
-func (b *responseBody) Read(p []byte) (int, error) {
-	n, err := b.body.Read(p)
-	if err == nil {
-		return n, nil
-	}
-
-	var tooLarge *http.MaxBytesError
-
-	switch {
-	case errors.Is(err, io.EOF):
-		b.rq.responseReceived()
-	case errors.As(err, &tooLarge):
-		b.rq.refuse(refusal{
-			status: http.StatusBadGateway,
-			action: requestlog.ActionTooLarge,
-			limit:  "SWWAF_RESPONSE_MAX_BYTES",
-		})
-
-		return n, errResponseTooLarge
-	case b.rq.in.Context().Err() == nil:
-		// The answer broke off, not because the client went away. If a
-		// timeout cut it, that refusal came first and is the one kept.
-		b.rq.refuse(refusal{
-			status: http.StatusBadGateway,
-			action: requestlog.ActionUpstreamError,
-		})
-	}
-
-	return n, err
-}
-
-// Close closes the app's body.
-func (b *responseBody) Close() error {
-	return b.body.Close()
-}
-
-// upgradedConn is the connection to the app once the app has switched
-// protocols, as for a WebSocket. ReverseProxy writes to it what the client
-// sends and reads from it what the app sends, on goroutines of its own,
-// until the connection closes; it counts the bytes each way, for the byte
-// limits.
-type upgradedConn struct {
-	io.ReadWriteCloser
-
-	// fromApp is how many bytes the app has sent, and toApp how many the
-	// client has.
-	fromApp atomic.Int64
-	toApp   atomic.Int64
-}
-
-// Read reads what the app sends.
-func (c *upgradedConn) Read(p []byte) (int, error) {
-	n, err := c.ReadWriteCloser.Read(p)
-	c.fromApp.Add(int64(n))
-
-	return n, err
-}
-
-// Write sends the app what the client sent.
-func (c *upgradedConn) Write(p []byte) (int, error) {
-	n, err := c.ReadWriteCloser.Write(p)
-	c.toApp.Add(int64(n))
-
-	return n, err
-}
-
-// CloseWrite tells the app that the client sends no more, while what the
-// app sends still passes. ReverseProxy calls it once the client has
-// stopped sending, and closes the connection there if it is not supported.
-func (c *upgradedConn) CloseWrite() error {
-	conn, ok := c.ReadWriteCloser.(interface{ CloseWrite() error })
-	if !ok {
-		return http.ErrNotSupported
-	}
-
-	return conn.CloseWrite()
-}
-
-// limitBody returns body, cut off with an *http.MaxBytesError after
-// maxBytes, or unchanged if maxBytes is zero, which is off.
-func limitBody(body io.ReadCloser, maxBytes int64) io.ReadCloser {
-	if maxBytes == 0 {
-		return body
-	}
-
-	// Without a ResponseWriter, MaxBytesReader only counts and cuts off.
-	return http.MaxBytesReader(nil, body, maxBytes)
-}
-
-// responseWriter is the response to the client. It notes the status and
-// size for the log line, and the first error writing to the client.
-type responseWriter struct {
-	http.ResponseWriter
-
-	// status is the final status sent, or zero before one is.
-	status int
-	bytes  int64
-	err    error
-}
-
-// WriteHeader sends the status and headers. An informational 1xx status
-// is passed on and the final status still comes later.
-func (w *responseWriter) WriteHeader(status int) {
-	if status >= http.StatusOK && w.status == 0 {
-		w.status = status
-	}
-
-	w.ResponseWriter.WriteHeader(status)
-}
-
-// Write sends part of the body.
-func (w *responseWriter) Write(p []byte) (int, error) {
-	if w.status == 0 {
-		w.status = http.StatusOK
-	}
-
-	n, err := w.ResponseWriter.Write(p)
-	w.bytes += int64(n)
-	w.noteError(err)
-
-	return n, err
-}
-
-// FlushError sends what has been written so far.
-// http.ResponseController calls it, as ReverseProxy does after each
-// write.
-func (w *responseWriter) FlushError() error {
-	err := http.NewResponseController(w.ResponseWriter).Flush()
-	w.noteError(err)
-
-	return err
-}
-
-// Hijack takes over the connection to the client, which ReverseProxy does
-// only to pass on the app's 101 Switching Protocols: that is then the
-// status sent.
-func (w *responseWriter) Hijack() (net.Conn, *bufio.ReadWriter, error) {
-	conn, buffered, err := http.NewResponseController(w.ResponseWriter).Hijack()
-	if err == nil {
-		w.status = http.StatusSwitchingProtocols
-	}
-
-	return conn, buffered, err
-}
-
-// Unwrap lets http.ResponseController reach net/http's own
-// ResponseWriter for what responseWriter does not do itself.
-func (w *responseWriter) Unwrap() http.ResponseWriter {
-	return w.ResponseWriter
-}
-
-// noteError keeps the first error writing to the client.
-func (w *responseWriter) noteError(err error) {
-	if w.err == nil {
-		w.err = err
-	}
-}

internal/proxy/client.go

@@ -1,142 +0,0 @@
-package proxy
-
-import (
-	"crypto/rand"
-	"net/http"
-	"net/netip"
-	"slices"
-	"strings"
-)
-
-// peerAddress is the address of the request's TCP peer, normally traefik.
-func peerAddress(r *http.Request) netip.Addr {
-	addrPort, err := netip.ParseAddrPort(r.RemoteAddr)
-	if err != nil {
-		return netip.Addr{}
-	}
-
-	return addrPort.Addr().Unmap()
-}
-
-// clientAddress works out who the client is. A peer outside the trusted
-// proxies is the client, and what it says in X-Forwarded-For is ignored.
-// For a peer inside them, X-Forwarded-For is read from the right, and the
-// first address outside them is the client; if every address in it is
-// inside, the leftmost is, and with no header, the peer. An entry that is
-// not an address ends the reading, since nothing to its left can be
-// believed.
-func clientAddress(
-	peer netip.Addr, forwardedFor []string, trusted []netip.Prefix,
-) netip.Addr {
-	client := peer
-	if !isInside(peer, trusted) {
-		return client
-	}
-
-	entries := strings.Split(strings.Join(forwardedFor, ","), ",")
-	for _, entry := range slices.Backward(entries) {
-		addr, err := netip.ParseAddr(strings.TrimSpace(entry))
-		if err != nil {
-			break
-		}
-
-		client = addr.Unmap()
-		if !isInside(client, trusted) {
-			break
-		}
-	}
-
-	return client
-}
-
-// requestIDHeader carries the request's id, from traefik and to the app.
-const requestIDHeader = "X-Request-ID"
-
-// requestID is the request's id: the one a trusted proxy sent, or a new
-// random one. A peer outside the trusted proxies did not come through
-// traefik, so the id it sends is its own claim, and is replaced.
-func requestID(r *http.Request, peerTrusted bool) string {
-	id := r.Header.Get(requestIDHeader)
-	if !peerTrusted || id == "" {
-		id = rand.Text()
-	}
-
-	return id
-}
-
-// scheme is how the client reached traefik, as a trusted proxy says in
-// X-Forwarded-Proto, or otherwise http, the only scheme smallwebwaf
-// serves.
-func scheme(r *http.Request, peerTrusted bool) string {
-	proto := r.Header.Get("X-Forwarded-Proto")
-	if !peerTrusted || proto == "" {
-		return "http"
-	}
-
-	return proto
-}
-
-// clientGroup is the client a request is counted toward: its IPv4
-// address, or its IPv6 group, the netblock its IPv6 address is in of the
-// length SWWAF_IPV6_GROUP_PREFIX sets, a /64 by default, since one abuser
-// usually holds a whole /64. An IPv4 address in IPv6 form counts as IPv4.
-func (h *handler) clientGroup(addr netip.Addr) netip.Prefix {
-	addr = addr.Unmap()
-	if addr.Is6() {
-		return netip.PrefixFrom(addr, h.config.IPv6GroupPrefix).Masked()
-	}
-
-	return netip.PrefixFrom(addr, addr.BitLen())
-}
-
-// isInside reports whether addr is in one of the netblocks.
-func isInside(addr netip.Addr, netblocks []netip.Prefix) bool {
-	return slices.ContainsFunc(netblocks, func(netblock netip.Prefix) bool {
-		return netblock.Contains(addr)
-	})
-}
-
-// setForwardedHeaders sets the headers in which the app learns about the
-// client, so that it sees what it would see from traefik directly. A
-// trusted proxy's forwarded headers pass on, with the proxy's own address
-// added to X-Forwarded-For. Those of any other peer are its own claims and
-// are replaced: X-Forwarded-For names the peer, X-Forwarded-Host the host
-// it asked for, and X-Forwarded-Proto plain http, which is how it reached
-// smallwebwaf.
-func setForwardedHeaders(in, out *http.Request, peer netip.Addr, trusted bool) {
-	forwardedFor := peer.String()
-
-	if trusted {
-		// ReverseProxy removes these from out before Rewrite.
-		for _, name := range []string{"Forwarded", "X-Forwarded-Host", "X-Forwarded-Proto"} {
-			values, ok := in.Header[name]
-			if ok {
-				out.Header[name] = values
-			}
-		}
-
-		prior := in.Header.Values("X-Forwarded-For")
-		if len(prior) > 0 {
-			forwardedFor = strings.Join(prior, ", ") + ", " + forwardedFor
-		}
-
-		out.Header.Set("X-Forwarded-For", forwardedFor)
-
-		return
-	}
-
-	// ReverseProxy has removed Forwarded and the three set below; these
-	// are the other headers in which traefik tells the app about the
-	// client and its request.
-	for _, name := range []string{
-		"X-Forwarded-Port", "X-Forwarded-Server", "X-Forwarded-Uri",
-		"X-Forwarded-Method", "X-Forwarded-Prefix", "X-Forwarded-Tls-Client-Cert",
-		"X-Forwarded-Tls-Client-Cert-Info", "X-Real-Ip",
-	} {
-		out.Header.Del(name)
-	}
-
-	out.Header.Set("X-Forwarded-For", forwardedFor)
-	out.Header.Set("X-Forwarded-Host", in.Host)
-	out.Header.Set("X-Forwarded-Proto", "http")
-}

internal/proxy/client_test.go

@@ -1,165 +0,0 @@
-package proxy_test
-
-import (
-	"encoding/json"
-	"net/http"
-	"testing"
-)
-
-const (
-	// trustLocalhost trusts the address every test connects from, and a
-	// network for proxies in front of it.
-	trustLocalhost = localhost + "/32,10.0.0.0/8"
-	// appHost is the host every test asks for.
-	appHost = "app.example"
-	// client is the client's address, as a proxy names it.
-	client = "203.0.113.9"
-	// forwardedFor is the header that lists the client and its proxies,
-	// and forwardedProto the one that gives the scheme the client used.
-	forwardedFor   = "X-Forwarded-For"
-	forwardedProto = "X-Forwarded-Proto"
-	// secure is the scheme a client reached traefik with, and plain the
-	// one smallwebwaf serves.
-	secure = "https"
-	plain  = "http"
-)
-
-// appHeaders is what the app tells about the headers it received.
-type appHeaders struct {
-	Host           string `json:"host"`
-	ForwardedFor   string `json:"forwardedFor"`
-	ForwardedHost  string `json:"forwardedHost"`
-	ForwardedProto string `json:"forwardedProto"`
-	RealIP         string `json:"realIp"`
-}
-
-// clientAddressCase is a request and what smallwebwaf makes of it.
-type clientAddressCase struct {
-	name       string
-	env        map[string]string
-	header     http.Header
-	wantClient string
-	wantApp    appHeaders
-}
-
-func TestClientAddressAndForwardedHeaders(t *testing.T) {
-	t.Parallel()
-
-	for _, tc := range clientAddressCases() {
-		t.Run(tc.name, func(t *testing.T) {
-			t.Parallel()
-
-			got, line := requestWithHeaders(t, tc.env, tc.header)
-
-			tc.wantApp.Host = appHost
-			if got != tc.wantApp {
-				t.Errorf("app received %+v, want %+v", got, tc.wantApp)
-			}
-
-			if line.ClientIP != tc.wantClient || line.PeerIP != localhost {
-				t.Errorf("log line has client_ip %q and peer_ip %q, want %q and %q",
-					line.ClientIP, line.PeerIP, tc.wantClient, localhost)
-			}
-		})
-	}
-}
-
-// clientAddressCases are the requests TestClientAddressAndForwardedHeaders
-// sends, from 127.0.0.1, which the default trusted proxies leave out.
-func clientAddressCases() []clientAddressCase {
-	trusted := map[string]string{trustedProxies: trustLocalhost}
-	forged := http.Header{
-		forwardedFor:       {client},
-		"X-Forwarded-Host": {"forged.example"},
-		forwardedProto:     {secure},
-		"X-Real-Ip":        {client},
-	}
-	replaced := appHeaders{
-		ForwardedFor: localhost, ForwardedHost: appHost, ForwardedProto: plain,
-	}
-
-	return []clientAddressCase{{
-		name: "a peer outside the trusted proxies is the client, " +
-			"and its forwarded headers are replaced",
-		header: forged, wantClient: localhost, wantApp: replaced,
-	}, {
-		name:   "set but empty, the trusted proxies trust nothing",
-		env:    map[string]string{trustedProxies: ""},
-		header: forged, wantClient: localhost, wantApp: replaced,
-	}, {
-		name: "behind a trusted peer, the client is the first address " +
-			"outside the trusted proxies from the right",
-		env: trusted,
-		header: http.Header{
-			forwardedFor:       {"198.51.100.7, " + client + ", 10.0.0.2"},
-			"X-Forwarded-Host": {appHost},
-			forwardedProto:     {secure},
-			"X-Real-Ip":        {client},
-		},
-		wantClient: client,
-		wantApp: appHeaders{
-			ForwardedFor:  "198.51.100.7, " + client + ", 10.0.0.2, " + localhost,
-			ForwardedHost: appHost, ForwardedProto: secure, RealIP: client,
-		},
-	}, {
-		name:       "when every address is a trusted proxy, the leftmost is the client",
-		env:        trusted,
-		header:     http.Header{forwardedFor: {"10.0.0.5, 10.0.0.2"}},
-		wantClient: "10.0.0.5",
-		wantApp:    appHeaders{ForwardedFor: "10.0.0.5, 10.0.0.2, " + localhost},
-	}, {
-		name:       "with no header, a trusted peer is the client",
-		env:        trusted,
-		wantClient: localhost,
-		wantApp:    appHeaders{ForwardedFor: localhost},
-	}, {
-		name:       "an entry that is not an address ends the reading",
-		env:        trusted,
-		header:     http.Header{forwardedFor: {client + ", unknown, 10.0.0.2"}},
-		wantClient: "10.0.0.2",
-		wantApp: appHeaders{
-			ForwardedFor: client + ", unknown, 10.0.0.2, " + localhost,
-		},
-	}, {
-		name:       "several header lines are read as one list",
-		env:        trusted,
-		header:     http.Header{forwardedFor: {"2001:db8::7", "10.0.0.2"}},
-		wantClient: "2001:db8::7",
-		wantApp:    appHeaders{ForwardedFor: "2001:db8::7, 10.0.0.2, " + localhost},
-	}}
-}
-
-// requestWithHeaders sends a request for appHost with header through
-// smallwebwaf, with the settings in env, and returns the headers the app
-// received and the request's log line.
-func requestWithHeaders(
-	t *testing.T, env map[string]string, header http.Header,
-) (appHeaders, logLine) {
-	t.Helper()
-
-	app := startApp(t, func(w http.ResponseWriter, r *http.Request) {
-		_ = json.NewEncoder(w).Encode(appHeaders{
-			Host:           r.Host,
-			ForwardedFor:   r.Header.Get(forwardedFor),
-			ForwardedHost:  r.Header.Get("X-Forwarded-Host"),
-			ForwardedProto: r.Header.Get(forwardedProto),
-			RealIP:         r.Header.Get("X-Real-IP"),
-		})
-	})
-	addr, out := startProxy(t, app.URL, env)
-
-	req := newRequest(t, http.MethodGet, addr, "/", http.NoBody)
-	req.Host = appHost
-	req.Header = header.Clone()
-
-	answered := do(t, req)
-
-	var got appHeaders
-
-	err := json.Unmarshal(answered.body, &got)
-	if err != nil {
-		t.Fatalf("decode the app's answer %q: %v", answered.body, err)
-	}
-
-	return got, out.requestLine(t)
-}

internal/proxy/countries.go

@@ -1,21 +0,0 @@
-package proxy
-
-import (
-	"slices"
-)
-
-// countryDenied reports whether the country lists refuse the request, by
-// the client's country as it was looked up. A client without a country,
-// or whose country cannot be found, is refused only by
-// SWWAF_EXCLUSIVELY_ALLOWED_COUNTRIES.
-func (rq *request) countryDenied() bool {
-	denied := rq.h.config.DeniedCountries
-	allowed := rq.h.config.ExclusivelyAllowedCountries
-	country := rq.line.Country
-
-	if slices.Contains(denied, country) {
-		return true
-	}
-
-	return len(allowed) > 0 && !slices.Contains(allowed, country)
-}

internal/proxy/health_test.go

@@ -1,56 +0,0 @@
-package proxy_test
-
-import (
-	"net/http"
-	"sync/atomic"
-	"testing"
-
-	"sneak.berlin/go/smallwebwaf/internal/proxy"
-	"sneak.berlin/go/smallwebwaf/internal/requestlog"
-)
-
-func TestHealthEndpointIsAnsweredBeforeAnyCheck(t *testing.T) {
-	t.Parallel()
-
-	var calls atomic.Int32
-
-	app := startApp(t, func(http.ResponseWriter, *http.Request) {
-		calls.Add(1)
-	})
-	// With a limit of one request a minute, any request counted before
-	// the last one would have it refused.
-	addr, out := startProxy(t, app.URL, map[string]string{rateLimitPerMinute: "1"})
-
-	const (
-		healthChecks = 3
-		contentType  = "text/plain; charset=utf-8"
-	)
-
-	for range healthChecks {
-		got := get(t, addr, proxy.HealthPath)
-		wantStatus(t, got, http.StatusOK)
-
-		if string(got.body) != "ok\n" || got.header.Get("Content-Type") != contentType {
-			t.Errorf("health endpoint answered %q with Content-Type %q, want ok "+
-				"with %q", got.body, got.header.Get("Content-Type"), contentType)
-		}
-	}
-
-	wantStatus(t, get(t, addr, "/"), http.StatusOK)
-
-	lines := out.requestLines(t, healthChecks+1)
-	for _, line := range lines[:healthChecks] {
-		wantLine(t, line, http.StatusOK, requestlog.ActionAdmin)
-
-		if line.ResponseContentType != contentType {
-			t.Errorf("health check's log line has response_content_type %q, "+
-				"want %q", line.ResponseContentType, contentType)
-		}
-	}
-
-	wantLine(t, lines[healthChecks], http.StatusOK, requestlog.ActionForward)
-
-	if calls.Load() != 1 {
-		t.Errorf("the app was called %d times, want once", calls.Load())
-	}
-}

internal/proxy/limits_test.go

@@ -1,162 +0,0 @@
-package proxy_test
-
-import (
-	"bytes"
-	"errors"
-	"io"
-	"net/http"
-	"strconv"
-	"sync/atomic"
-	"testing"
-
-	"sneak.berlin/go/smallwebwaf/internal/requestlog"
-)
-
-// sizeLimit is the size limit the tests set, 1K as a setting.
-const (
-	sizeLimit        = 1 << 10
-	sizeLimitSetting = "1K"
-)
-
-func TestRequestBodyLimit(t *testing.T) {
-	t.Parallel()
-
-	for _, tc := range []struct {
-		name string
-		size int
-		// announced sends the size in Content-Length; otherwise the body
-		// is sent in chunks with no length given.
-		announced bool
-		want      int
-		action    string
-		// refusedBeforeApp is a refusal before anything reaches the app.
-		// A body over the limit with no length given has already partly
-		// reached the app when it is refused.
-		refusedBeforeApp bool
-	}{
-		{"announced, over the limit", 2 * sizeLimit, true,
-			http.StatusRequestEntityTooLarge, requestlog.ActionTooLarge, true},
-		{"announced, at the limit", sizeLimit, true,
-			http.StatusOK, requestlog.ActionForward, false},
-		{"not announced, over the limit", 4 * sizeLimit, false,
-			http.StatusRequestEntityTooLarge, requestlog.ActionTooLarge, false},
-		{"not announced, at the limit", sizeLimit, false,
-			http.StatusOK, requestlog.ActionForward, false},
-	} {
-		t.Run(tc.name, func(t *testing.T) {
-			t.Parallel()
-
-			var calls atomic.Int32
-
-			app := startApp(t, func(_ http.ResponseWriter, r *http.Request) {
-				calls.Add(1)
-
-				_, _ = io.Copy(io.Discard, r.Body)
-			})
-			addr, out := startProxy(t, app.URL, map[string]string{
-				requestMaxBytes: sizeLimitSetting,
-				metricsToken:    token,
-			})
-
-			var body io.Reader = bytes.NewReader(make([]byte, tc.size))
-			if !tc.announced {
-				body = io.MultiReader(body) // hides the length
-			}
-
-			wantStatus(t, do(t, newRequest(t, http.MethodPost, addr, "/upload", body)),
-				tc.want)
-			wantLine(t, out.requestLine(t), tc.want, tc.action)
-
-			hits := 0
-			if tc.action == requestlog.ActionTooLarge {
-				hits = 1
-			}
-
-			wantLimitHits(t, addr, requestMaxBytes, hits)
-
-			if tc.refusedBeforeApp && calls.Load() != 0 {
-				t.Errorf("the app was called %d times, want never", calls.Load())
-			}
-		})
-	}
-}
-
-func TestResponseBodyLimit(t *testing.T) {
-	t.Parallel()
-
-	for _, tc := range []struct {
-		name string
-		size int
-		// announced sends the size in Content-Length; otherwise the body
-		// is sent in chunks with no length given.
-		announced bool
-		want      int
-		action    string
-		// received is how much of a body the client gets, and cutOff
-		// whether the connection is then cut.
-		received int
-		cutOff   bool
-	}{
-		{"announced, over the limit", 2 * sizeLimit, true, http.StatusBadGateway,
-			requestlog.ActionTooLarge, len("Bad Gateway\n"), false},
-		{"announced, at the limit", sizeLimit, true, http.StatusOK,
-			requestlog.ActionForward, sizeLimit, false},
-		{"not announced, over the limit", 4 * sizeLimit, false, http.StatusOK,
-			requestlog.ActionTooLarge, sizeLimit, true},
-		{"not announced, at the limit", sizeLimit, false, http.StatusOK,
-			requestlog.ActionForward, sizeLimit, false},
-	} {
-		t.Run(tc.name, func(t *testing.T) {
-			t.Parallel()
-
-			app := startApp(t, func(w http.ResponseWriter, _ *http.Request) {
-				answerWithSize(w, tc.size, tc.announced)
-			})
-			addr, out := startProxy(t, app.URL, map[string]string{
-				responseMaxBytes: sizeLimitSetting,
-				metricsToken:     token,
-			})
-
-			got := get(t, addr, "/download")
-			wantStatus(t, got, tc.want)
-
-			if len(got.body) != tc.received ||
-				errors.Is(got.err, io.ErrUnexpectedEOF) != tc.cutOff {
-				t.Errorf("client got %d bytes (%v), want %d",
-					len(got.body), got.err, tc.received)
-			}
-
-			line := out.requestLine(t)
-			wantLine(t, line, tc.want, tc.action)
-
-			if line.UpstreamStatus != http.StatusOK {
-				t.Errorf("log line has upstream_status %d", line.UpstreamStatus)
-			}
-
-			hits := 0
-			if tc.action == requestlog.ActionTooLarge {
-				hits = 1
-			}
-
-			wantLimitHits(t, addr, responseMaxBytes, hits)
-		})
-	}
-}
-
-// answerWithSize answers with a body of size bytes, announced in
-// Content-Length or sent in chunks with no length given.
-func answerWithSize(w http.ResponseWriter, size int, announced bool) {
-	body := make([]byte, size)
-	if announced {
-		w.Header().Set("Content-Length", strconv.Itoa(size))
-		_, _ = w.Write(body)
-
-		return
-	}
-
-	// Sending part of it before the end keeps Go's server from working
-	// out the length.
-	_, _ = w.Write(body[:size/2])
-	_ = http.NewResponseController(w).Flush()
-	_, _ = w.Write(body[size/2:])
-}

internal/proxy/passthrough_test.go

@@ -1,556 +0,0 @@
-package proxy_test
-
-import (
-	"bufio"
-	"bytes"
-	"errors"
-	"io"
-	"net/http"
-	"reflect"
-	"slices"
-	"strings"
-	"sync/atomic"
-	"testing"
-	"time"
-
-	"sneak.berlin/go/smallwebwaf/internal/config"
-	"sneak.berlin/go/smallwebwaf/internal/proxy"
-	"sneak.berlin/go/smallwebwaf/internal/ratelimit"
-	"sneak.berlin/go/smallwebwaf/internal/requestlog"
-)
-
-// A request target with an escaped slash and space in its path, and a
-// query with a parameter ReverseProxy cannot parse.
-const (
-	rawPath  = "/some%2Fpath/with%20space"
-	rawQuery = "b=2&a=1&bad=%zz;x"
-)
-
-// chunkSize is the size of each part of a body a test sends in parts.
-const chunkSize = 1 << 10
-
-var errNotStreamed = errors.New("the first part never reached the app")
-
-// appSaw is what the app received.
-type appSaw struct {
-	method string
-	target string
-	header http.Header
-	body   []byte
-}
-
-func TestPassesRequestAndAnswerUnchanged(t *testing.T) {
-	t.Parallel()
-
-	requestBody := bytes.Repeat([]byte("request body "), 8000)
-	answerBody := bytes.Repeat([]byte("answer body "), 8000)
-	saw := make(chan appSaw, 1)
-
-	app := startApp(t, func(w http.ResponseWriter, r *http.Request) {
-		body, _ := io.ReadAll(r.Body)
-		saw <- appSaw{r.Method, r.RequestURI, r.Header.Clone(), body}
-
-		w.Header().Set("X-App", "yes")
-		w.Header().Add("Set-Cookie", "a=1")
-		w.Header().Add("Set-Cookie", "b=2")
-		w.WriteHeader(http.StatusTeapot)
-		_, _ = w.Write(answerBody)
-	})
-	addr, out := startProxy(t, app.URL, nil)
-
-	req := newRequest(t, http.MethodPatch, addr, rawPath+"?"+rawQuery,
-		bytes.NewReader(requestBody))
-	req.Header.Add("X-Test", "one")
-	req.Header.Add("X-Test", "two")
-	req.Header.Set("User-Agent", "test-agent")
-
-	got := do(t, req)
-
-	wantAppSaw(t, <-saw, requestBody)
-	wantAnswer(t, got, answerBody)
-
-	line := out.requestLine(t)
-	wantLine(t, line, http.StatusTeapot, requestlog.ActionForward)
-	wantRequestFields(t, line, addr, len(requestBody), len(answerBody))
-}
-
-func TestPassesThePathAsSent(t *testing.T) {
-	t.Parallel()
-
-	for _, path := range []string{
-		// An encoded slash and a character Go escapes: |, ^, and é sent
-		// as its UTF-8 bytes.
-		"/a%2Fb|c", "/feat%2Fx/file^1", "/x%2Fy/café",
-		// A path starting with //, which Go would send as a scheme and
-		// host if it were put in URL.Opaque.
-		"//a%2Fb",
-	} {
-		t.Run(path, func(t *testing.T) {
-			t.Parallel()
-
-			saw := make(chan string, 1)
-			app := startApp(t, func(_ http.ResponseWriter, r *http.Request) {
-				saw <- r.RequestURI
-			})
-			addr, out := startProxy(t, app.URL, nil)
-
-			conn := dial(t, addr)
-			send(t, conn, "GET "+path+"?q=1 HTTP/1.1\r\nHost: "+appHost+"\r\n\r\n")
-
-			got := readResponse(t, conn)
-			if got.status != http.StatusOK {
-				t.Fatalf("status %d, want %d", got.status, http.StatusOK)
-			}
-
-			target := <-saw
-			if target != path+"?q=1" {
-				t.Errorf("app saw %s, want %s", target, path+"?q=1")
-			}
-
-			line := out.requestLine(t)
-			if line.Path != path {
-				t.Errorf("log line has path %s, want %s", line.Path, path)
-			}
-		})
-	}
-}
-
-// wantAppSaw checks that the app received the test's request unchanged.
-func wantAppSaw(t *testing.T, saw appSaw, body []byte) {
-	t.Helper()
-
-	if saw.method != http.MethodPatch || saw.target != rawPath+"?"+rawQuery {
-		t.Errorf("app saw %s %s, want %s %s", saw.method, saw.target,
-			http.MethodPatch, rawPath+"?"+rawQuery)
-	}
-
-	if !slices.Equal(saw.header.Values("X-Test"), []string{"one", "two"}) {
-		t.Errorf("app saw X-Test %q", saw.header.Values("X-Test"))
-	}
-
-	if saw.header.Get("User-Agent") != "test-agent" {
-		t.Errorf("app saw User-Agent %q", saw.header.Get("User-Agent"))
-	}
-
-	if !bytes.Equal(saw.body, body) {
-		t.Errorf("app saw a body of %d bytes, want the %d sent",
-			len(saw.body), len(body))
-	}
-}
-
-// wantAnswer checks that the client received the app's answer unchanged.
-func wantAnswer(t *testing.T, got answer, body []byte) {
-	t.Helper()
-
-	wantStatus(t, got, http.StatusTeapot)
-
-	if got.header.Get("X-App") != "yes" {
-		t.Errorf("client got X-App %q", got.header.Get("X-App"))
-	}
-
-	if !slices.Equal(got.header.Values("Set-Cookie"), []string{"a=1", "b=2"}) {
-		t.Errorf("client got Set-Cookie %q", got.header.Values("Set-Cookie"))
-	}
-
-	if got.err != nil || !bytes.Equal(got.body, body) {
-		t.Errorf("client got %d bytes (%v), want the %d the app sent",
-			len(got.body), got.err, len(body))
-	}
-}
-
-// wantRequestFields checks the log line's fields about the request. Its
-// time, its id and its timings are checked only for being there.
-func wantRequestFields(t *testing.T, line logLine, host string, sent, received int) {
-	t.Helper()
-
-	bytes := float64(sent + received)
-
-	want := withTimings(line, requestlog.Line{
-		Type: requestType, Time: line.Time, Instance: "app",
-		ClientIP: localhost, Method: http.MethodPatch, Scheme: plain, Host: host,
-		Path: rawPath, Query: rawQuery, Protocol: protocol,
-		Status: http.StatusTeapot, RequestBytes: int64(sent),
-		ResponseBytes: int64(received), UserAgent: "test-agent",
-		RequestID: line.RequestID, PeerIP: localhost, ClientGroup: localhost + "/32",
-		ContentLength: int64(sent), ResponseContentType: "text/plain; charset=utf-8",
-		UpstreamStatus: http.StatusTeapot, Action: requestlog.ActionForward,
-		Counts: ratelimit.Counts{
-			Minute: 1, Hour: 1, Day: 1,
-			MinuteBytes: bytes, HourBytes: bytes, DayBytes: bytes,
-		},
-	})
-	if !reflect.DeepEqual(line.Line, want) {
-		t.Errorf("log line\n%+v\nwant\n%+v", line.Line, want)
-	}
-
-	_, err := time.Parse(time.RFC3339, line.Time)
-	if err != nil || line.RequestID == "" || line.DurationTotal <= 0 ||
-		line.DurationUpstreamTotal == nil || *line.DurationUpstreamTotal <= 0 {
-		t.Errorf("log line has time %q, request_id %q and durations %v and %v",
-			line.Time, line.RequestID, line.DurationTotal,
-			line.fields["duration_upstream_total"])
-	}
-}
-
-func TestAddsNoContentTypeTheAppDidNotSend(t *testing.T) {
-	t.Parallel()
-
-	const typed = "text/plain"
-
-	app := startApp(t, func(w http.ResponseWriter, r *http.Request) {
-		if r.URL.Path == "/typed" {
-			w.Header().Set("Content-Type", typed)
-		} else {
-			// The key with no value keeps Go's server from adding one.
-			w.Header()["Content-Type"] = nil
-		}
-
-		_, _ = io.WriteString(w, "<!doctype html><title>page</title>")
-	})
-	addr, _ := startProxy(t, app.URL, nil)
-
-	got := get(t, addr, "/")
-	if got.header.Values("Content-Type") != nil {
-		t.Errorf("client got Content-Type %q, want none",
-			got.header.Get("Content-Type"))
-	}
-
-	got = get(t, addr, "/typed")
-	if got.header.Get("Content-Type") != typed {
-		t.Errorf("client got Content-Type %q, want %q",
-			got.header.Get("Content-Type"), typed)
-	}
-}
-
-func TestStreamsTheRequestBody(t *testing.T) {
-	t.Parallel()
-
-	chunk := bytes.Repeat([]byte("x"), chunkSize)
-	firstArrived := make(chan struct{})
-
-	app := startApp(t, func(w http.ResponseWriter, r *http.Request) {
-		first := make([]byte, len(chunk))
-
-		_, err := io.ReadFull(r.Body, first)
-		if err != nil {
-			return
-		}
-
-		close(firstArrived)
-
-		rest, _ := io.ReadAll(r.Body)
-		_, _ = w.Write(rest)
-	})
-	addr, _ := startProxy(t, app.URL, nil)
-
-	body, writer := io.Pipe()
-
-	go func() {
-		_, _ = writer.Write(chunk)
-
-		select {
-		case <-firstArrived:
-			_, _ = writer.Write(chunk)
-			_ = writer.Close()
-		case <-time.After(waitLimit):
-			_ = writer.CloseWithError(errNotStreamed)
-		}
-	}()
-
-	got := do(t, newRequest(t, http.MethodPost, addr, "/upload", body))
-	if got.err != nil || !bytes.Equal(got.body, chunk) {
-		t.Errorf("app read %d bytes after the first part (%v), want %d",
-			len(got.body), got.err, len(chunk))
-	}
-}
-
-func TestStreamsTheAnswerBody(t *testing.T) {
-	t.Parallel()
-
-	chunk := bytes.Repeat([]byte("y"), chunkSize)
-	firstArrived := make(chan struct{})
-
-	app := startApp(t, func(w http.ResponseWriter, _ *http.Request) {
-		_, _ = w.Write(chunk)
-		_ = http.NewResponseController(w).Flush()
-
-		select {
-		case <-firstArrived:
-			_, _ = w.Write(chunk)
-		case <-time.After(waitLimit):
-		}
-	})
-	addr, _ := startProxy(t, app.URL, nil)
-
-	req := newRequest(t, http.MethodGet, addr, "/download", http.NoBody)
-
-	res, err := newClient(t).Do(req)
-	if err != nil {
-		t.Fatalf("request: %v", err)
-	}
-
-	first := make([]byte, len(chunk))
-	_, err = io.ReadFull(res.Body, first)
-
-	close(firstArrived)
-
-	got := readAnswer(res)
-	if err != nil || got.err != nil || !bytes.Equal(got.body, chunk) {
-		t.Errorf("client read %d bytes after the first part (%v, %v), want %d",
-			len(got.body), err, got.err, len(chunk))
-	}
-}
-
-func TestUpgradedConnectionOutlastsTheTimeouts(t *testing.T) {
-	t.Parallel()
-
-	app := startApp(t, echoAfterUpgrade)
-	addr, out := startProxy(t, app.URL, map[string]string{
-		clientRequestTimeout:    shortTimeoutSetting,
-		clientResponseTimeout:   shortTimeoutSetting,
-		upstreamRequestTimeout:  shortTimeoutSetting,
-		upstreamResponseTimeout: shortTimeoutSetting,
-	})
-
-	conn := dial(t, addr)
-	send(t, conn, "GET /socket HTTP/1.1\r\nHost: app\r\n"+
-		"Connection: Upgrade\r\nUpgrade: websocket\r\n\r\n")
-
-	reader := bufio.NewReader(conn)
-
-	res, err := http.ReadResponse(reader, nil)
-	if err != nil {
-		t.Fatalf("read the answer to the upgrade: %v", err)
-	}
-
-	answered := time.Now()
-	_ = res.Body.Close()
-
-	if res.StatusCode != http.StatusSwitchingProtocols {
-		t.Fatalf("status %d, want %d", res.StatusCode, http.StatusSwitchingProtocols)
-	}
-
-	// Every timeout started before the upgrade was answered, the response
-	// timeouts last, at the end of the request: wait until just past
-	// shortTimeout after the answer was read, then use the connection.
-	time.Sleep(time.Until(answered.Add(shortTimeout + 100*time.Millisecond)))
-	send(t, conn, "still here\n")
-
-	echoed, err := reader.ReadString('\n')
-	if err != nil || echoed != "still here\n" {
-		t.Errorf("echo %q (%v), want %q", echoed, err, "still here\n")
-	}
-
-	_ = conn.Close()
-
-	wantLine(t, out.requestLine(t), http.StatusSwitchingProtocols,
-		requestlog.ActionForward)
-}
-
-// echoAfterUpgrade is an app that switches protocols on request, and then
-// sends back each line it receives.
-func echoAfterUpgrade(w http.ResponseWriter, r *http.Request) {
-	if r.Header.Get("Upgrade") != "websocket" {
-		http.Error(w, "not an upgrade", http.StatusBadRequest)
-
-		return
-	}
-
-	conn, buffered, err := http.NewResponseController(w).Hijack()
-	if err != nil {
-		return
-	}
-
-	defer func() {
-		_ = conn.Close()
-	}()
-
-	_, _ = buffered.WriteString("HTTP/1.1 101 Switching Protocols\r\n" +
-		"Connection: Upgrade\r\nUpgrade: websocket\r\n\r\n")
-	_ = buffered.Flush()
-
-	for {
-		line, err := buffered.ReadString('\n')
-		if err != nil {
-			return
-		}
-
-		_, _ = buffered.WriteString(line)
-		_ = buffered.Flush()
-	}
-}
-
-func TestAnswers502WhenTheAppSwitchesToAnotherProtocol(t *testing.T) {
-	t.Parallel()
-
-	// answerAfterUpgrade switches to websocket whatever the client asked
-	// for, and ReverseProxy passes on a switch only to the protocol the
-	// client asked for, here "websocket, foo".
-	app := startApp(t, answerAfterUpgrade)
-	addr, out := startProxy(t, app.URL, nil)
-
-	conn := dial(t, addr)
-	send(t, conn, "GET /ws HTTP/1.1\r\nHost: app\r\n"+
-		"Connection: Upgrade\r\nUpgrade: websocket, foo\r\n\r\n")
-
-	wantStatus(t, readResponse(t, conn), http.StatusBadGateway)
-	wantLine(t, out.requestLine(t), http.StatusBadGateway, requestlog.ActionUpstreamError)
-}
-
-func TestServerHasTheDefaultLimits(t *testing.T) {
-	t.Parallel()
-
-	cfg, err := config.FromEnvironment(func(string) (string, bool) { return "", false })
-	if err != nil {
-		t.Fatalf("default settings: %v", err)
-	}
-
-	server := proxy.New(proxy.Params{
-		Config:     cfg,
-		RequestLog: io.Discard,
-		ProcessLog: requestlog.NewProcessLogger(io.Discard, cfg.InstanceName, cfg.LogLevel),
-	})
-
-	if server.Addr != ":8080" || server.MaxHeaderBytes != 28<<10 ||
-		server.IdleTimeout != 2*time.Minute || server.ReadHeaderTimeout != time.Minute {
-		t.Errorf("server listens on %q with header limit %d, idle time %s and "+
-			"header timeout %s", server.Addr, server.MaxHeaderBytes,
-			server.IdleTimeout, server.ReadHeaderTimeout)
-	}
-}
-
-func TestRefusesHeadersOverTheLimit(t *testing.T) {
-	t.Parallel()
-
-	for _, tc := range []struct {
-		name  string
-		env   map[string]string
-		limit int
-	}{
-		{"by default", nil, 32 << 10},
-		{"as set", map[string]string{clientHeaderMaxBytes: "8K"}, 8 << 10},
-	} {
-		t.Run(tc.name, func(t *testing.T) {
-			t.Parallel()
-
-			var calls atomic.Int32
-
-			app := startApp(t, func(http.ResponseWriter, *http.Request) {
-				calls.Add(1)
-			})
-			addr, _ := startProxy(t, app.URL, tc.env)
-
-			// size counts every byte of the request: the request line,
-			// the headers and the blank line that ends them.
-			const (
-				start = "GET / HTTP/1.1\r\nHost: app\r\nX-Large: "
-				end   = "\r\n\r\n"
-			)
-
-			for _, sent := range []struct{ size, want int }{
-				{tc.limit, http.StatusOK},
-				{tc.limit + 1, http.StatusRequestHeaderFieldsTooLarge},
-			} {
-				conn := dial(t, addr)
-				send(t, conn,
-					start+strings.Repeat("a", sent.size-len(start)-len(end))+end)
-				wantStatus(t, readResponse(t, conn), sent.want)
-			}
-
-			if calls.Load() != 1 {
-				t.Errorf("the app was called %d times, want once", calls.Load())
-			}
-		})
-	}
-}
-
-func TestAnswers502WhenTheAppCannotBeReached(t *testing.T) {
-	t.Parallel()
-
-	// No test can listen on port 1: listening on port 0 gets one from 32768 up.
-	addr, out := startProxy(t, "http://"+localhost+":1", nil)
-
-	wantStatus(t, get(t, addr, "/"), http.StatusBadGateway)
-
-	line := out.requestLine(t)
-	wantLine(t, line, http.StatusBadGateway, requestlog.ActionUpstreamError)
-
-	// There never was a connection to the app, nor an answer from it.
-	wantTimings(t, line, "duration_total", "duration_checks",
-		"duration_upstream_total")
-
-	logged := slices.ContainsFunc(out.lines(t), func(line map[string]any) bool {
-		return line["type"] == "process" && line["msg"] == "request to the app failed"
-	})
-	if !logged {
-		t.Errorf("no process line says the request to the app failed")
-	}
-}
-
-func TestLogLevelHoldsBackNoRequestLine(t *testing.T) {
-	t.Parallel()
-
-	// At error the warning that the request to the app failed is held back,
-	// and is written before the answer is.
-	addr, out := startProxy(t, "http://"+localhost+":1", map[string]string{
-		"SWWAF_LOG_LEVEL": "error",
-	})
-
-	wantStatus(t, get(t, addr, "/"), http.StatusBadGateway)
-	wantLine(t, out.requestLine(t), http.StatusBadGateway, requestlog.ActionUpstreamError)
-
-	for _, line := range out.lines(t) {
-		if line["type"] == "process" {
-			t.Errorf("process line %v, want none at error", line)
-		}
-	}
-}
-
-func TestLogsAnAnswerThatBrokeOff(t *testing.T) {
-	t.Parallel()
-
-	app := startApp(t, func(w http.ResponseWriter, _ *http.Request) {
-		_, _ = io.WriteString(w, "the first part")
-		_ = http.NewResponseController(w).Flush()
-
-		panic(http.ErrAbortHandler) // drops the connection mid-answer
-	})
-	addr, out := startProxy(t, app.URL, nil)
-
-	got := get(t, addr, "/")
-	if string(got.body) != "the first part" || !errors.Is(got.err, io.ErrUnexpectedEOF) {
-		t.Errorf("client read %q (%v), want the first part cut off", got.body, got.err)
-	}
-
-	wantLine(t, out.requestLine(t), http.StatusOK, requestlog.ActionUpstreamError)
-}
-
-func TestLogsAClientThatWentAway(t *testing.T) {
-	t.Parallel()
-
-	arrived := make(chan struct{})
-
-	app := startApp(t, func(_ http.ResponseWriter, r *http.Request) {
-		close(arrived)
-		<-r.Context().Done()
-	})
-	addr, out := startProxy(t, app.URL, nil)
-
-	conn := dial(t, addr)
-	send(t, conn, "GET /slow HTTP/1.1\r\nHost: app\r\n\r\n")
-
-	select {
-	case <-arrived:
-	case <-time.After(waitLimit):
-		t.Fatal("the request never reached the app")
-	}
-
-	_ = conn.Close()
-
-	line := out.requestLine(t)
-	if !line.Aborted || line.Status != 0 || line.Action != requestlog.ActionForward {
-		t.Errorf("log line has aborted %v, status %d and action %q, "+
-			"want true, 0 and %q",
-			line.Aborted, line.Status, line.Action, requestlog.ActionForward)
-	}
-}

internal/proxy/reputation.go

@@ -1,122 +0,0 @@
-package proxy
-
-import (
-	"context"
-	"time"
-
-	"sneak.berlin/go/smallwebwaf/internal/alerts"
-	"sneak.berlin/go/smallwebwaf/internal/bans"
-	"sneak.berlin/go/smallwebwaf/internal/ratelimit"
-	"sneak.berlin/go/smallwebwaf/internal/reputation"
-)
-
-// deny is the SWWAF_BLOCKLIST_ACTION and the SWWAF_REPUTATION_ACTION that
-// refuses the requests of a client a source lists.
-const deny = "deny"
-
-// blocklistDenied notes the blocklists that list the client, as
-// noteListed does, and reports whether SWWAF_BLOCKLIST_ACTION, being deny,
-// refuses the request. Being limit, it lowers the client's limits instead
-// (see limitPercentages), and being log, it does nothing more.
-func (rq *request) blocklistDenied() bool {
-	listedBy := rq.h.lists.ListedBy(rq.client)
-	rq.blocklisted = len(listedBy) > 0
-	rq.noteListed(listedBy, "listed by a blocklist")
-
-	return rq.blocklisted && rq.h.config.BlocklistAction == deny
-}
-
-// crowdSecBanned reports whether a decision of the CrowdSec decision list
-// on the client is in force at now. If one is, it notes the list, as
-// noteHit does, and bans the client until that decision ends.
-func (rq *request) crowdSecBanned(now time.Time) bool {
-	decision, listed := rq.h.lists.CrowdSecDecision(rq.client, now)
-	if !listed {
-		return false
-	}
-
-	rq.noteHit(bans.ReputationHit{Source: rq.h.config.CrowdSecDecisionsURL},
-		"listed by the CrowdSec decision list")
-	rq.banForCrowdSec(now, decision)
-
-	return true
-}
-
-// dnsblDenied notes the DNSBL zones whose verdict lists the client, as
-// noteListed does, and reports whether SWWAF_REPUTATION_ACTION, being
-// deny, refuses the request. Being limit, it lowers the client's limits
-// instead (see limitPercentages), and being log, it does nothing more. A
-// zone without a verdict on the client is asked about it in the
-// background, and the request does not wait for the answer. ctx is the
-// request's own context.
-func (rq *request) dnsblDenied(ctx context.Context) bool {
-	listedBy := rq.h.dnsbl.ListedBy(ctx, rq.client)
-	rq.dnsblListed = len(listedBy) > 0
-	rq.noteListed(listedBy, "listed by a DNSBL zone")
-
-	return rq.dnsblListed && rq.h.config.ReputationAction == deny
-}
-
-// abuseIPDBDenied notes AbuseIPDB, as noteHit does, with the score, when
-// its score of the client is a hit, and reports whether
-// SWWAF_REPUTATION_ACTION, being deny, refuses the request, as dnsblDenied
-// does for a zone. While SWWAF_ABUSEIPDB_KEY is unset it does nothing. A
-// client without a score is checked in the background, by the request's
-// address, if its history counts an offence, and the request does not
-// wait for the answer. The score is then used for each address of the
-// client. ctx is the request's own context.
-func (rq *request) abuseIPDBDenied(ctx context.Context) bool {
-	if rq.h.config.AbuseIPDBKey == "" {
-		return false
-	}
-
-	client := rq.h.clientGroup(rq.client)
-	held, _ := rq.h.limiter.Client(client)
-	offender := held.History.Offences != ratelimit.Offences{}
-
-	score, hit := rq.h.abuseIPDB.Hit(ctx, client, rq.client, offender)
-	if !hit {
-		return false
-	}
-
-	rq.abuseIPDBHit = true
-	rq.noteHit(bans.ReputationHit{Source: reputation.AbuseIPDBSource, Score: &score},
-		"scored by AbuseIPDB at or over SWWAF_ABUSEIPDB_MIN_SCORE")
-
-	return rq.h.config.ReputationAction == deny
-}
-
-// noteListed notes each of sources, the URLs of the blocklists or the
-// DNSBL zones, their keys masked, that list the client, as noteHit does,
-// with reason.
-func (rq *request) noteListed(sources []string, reason string) {
-	for _, source := range sources {
-		rq.noteHit(bans.ReputationHit{Source: source}, reason)
-	}
-}
-
-// noteHit adds hit's source, which lists the client, to the log line's
-// reputation, and hit to the notes of a ban the request makes, counts the
-// source in the metrics, and raises a reputation_hit alert with reason,
-// whose detail gives hit's source and score.
-func (rq *request) noteHit(hit bans.ReputationHit, reason string) {
-	detail := map[string]any{"source": hit.Source}
-	if hit.Score != nil {
-		detail["score"] = *hit.Score
-	}
-
-	rq.line.Reputation = append(rq.line.Reputation, hit.Source)
-	rq.reputation = append(rq.reputation, hit)
-	rq.h.metrics.ReputationHit(hit.Source)
-	rq.h.alerts.Raise(alerts.Alert{
-		Event:    alerts.EventReputationHit,
-		Host:     rq.site,
-		Client:   rq.client,
-		Netblock: rq.h.clientGroup(rq.client),
-		ASN:      rq.line.ASN,
-		ASName:   rq.line.ASName,
-		Country:  rq.line.Country,
-		Reason:   reason,
-		Detail:   detail,
-	})
-}

internal/proxy/request.go

@@ -1,956 +0,0 @@
-package proxy
-
-import (
-	"context"
-	"errors"
-	"io"
-	"net/http"
-	"net/http/httptrace"
-	"net/http/httputil"
-	"net/netip"
-	"os"
-	"slices"
-	"strings"
-	"sync"
-	"sync/atomic"
-	"time"
-
-	"sneak.berlin/go/smallwebwaf/internal/anomaly"
-	"sneak.berlin/go/smallwebwaf/internal/bans"
-	"sneak.berlin/go/smallwebwaf/internal/config"
-	"sneak.berlin/go/smallwebwaf/internal/lookup"
-	"sneak.berlin/go/smallwebwaf/internal/ratelimit"
-	"sneak.berlin/go/smallwebwaf/internal/requestlog"
-	"sneak.berlin/go/smallwebwaf/internal/rules"
-)
-
-// flushAfterEachWrite has ReverseProxy pass on each part of the app's
-// answer as soon as it arrives.
-const flushAfterEachWrite time.Duration = -1
-
-// refusal is smallwebwaf refusing a request, or refusing to go on with it:
-// the status the client is answered if the response has not started yet,
-// 0 to close the connection without an answer, the action the log line
-// names, and the setting whose size or time limit the request passed, if
-// that is why.
-type refusal struct {
-	status int
-	action string
-	limit  string
-}
-
-// decision is what the checks note of a request: its log line, and what
-// counting the request needs once it has ended. servewaf keeps a copy of it
-// until the request's report comes. It holds no credentials, since the log line
-// never does, and neither the request's objects nor their bodies.
-type decision struct {
-	line   requestlog.Line
-	client netip.Addr
-	// requestURI is the path with the query, as a ban's notes keep it.
-	requestURI string
-	// site is, in servewaf, the host the visitor asked for, which the
-	// alerts name, since one servewaf serves many sites. It is "" otherwise.
-	site string
-	// allowed is true for a question answered with DispositionAllow.
-	allowed bool
-	// lookedUp is true once the client's AS number and country have been
-	// looked up, whether or not an answer was there, and lookupAnswer is
-	// what the lookup gave then, the zero Answer while GeoJS had given none.
-	lookedUp     bool
-	lookupAnswer lookup.Answer
-	// skippedLookupWait is true for a request that did not wait for GeoJS and
-	// found no answer kept. SWWAF_UNKNOWN_LIMIT_PERCENT does not apply to it,
-	// so that not waiting never lowers its client's limits.
-	skippedLookupWait bool
-	// counted is true for a request the rate limits counted, whose bytes
-	// the byte limits count once it has ended. limitPercent and
-	// bytesPercent are then its client's limit percentages for the rate
-	// limits and for the byte limits.
-	counted                    bool
-	limitPercent, bytesPercent percentage
-	// attack is true for a request that matched a ban rule or asked for a
-	// trap path, ruleBlocked for one a block rule refused, and wafBlocked for
-	// one the Core Rule Set refused, each an offence its client's history
-	// counts.
-	attack, ruleBlocked, wafBlocked bool
-	// reputation is the reputation sources that list the client, for the
-	// notes of a ban the request makes.
-	reputation []bans.ReputationHit
-}
-
-// request is one request on its way through smallwebwaf, from the moment
-// its headers have been read to its log line.
-type request struct {
-	decision
-
-	h  *handler
-	in *http.Request
-	// rc sets the deadlines of the connection to the client.
-	rc   *http.ResponseController
-	out  *responseWriter
-	body *requestBody // nil for a request without a body
-
-	peer        netip.Addr
-	peerTrusted bool
-	// tokenRefused is true for a request refused for a missing or wrong
-	// token, an offence its client's history counts.
-	tokenRefused bool
-	// blocklisted is true once a blocklist is found to list the client,
-	// dnsblListed once a DNSBL zone's verdict is, and abuseIPDBHit once
-	// AbuseIPDB's score of it is a hit.
-	blocklisted, dnsblListed, abuseIPDBHit bool
-	start                                  time.Time
-	// checked is when the checks were done, and upstreamStart when the
-	// request was handed to the app.
-	checked       time.Time
-	upstreamStart time.Time
-	// cancel ends the request to the app.
-	cancel context.CancelFunc
-	// refused is the first refusal, from whichever goroutine meets it.
-	refused atomic.Pointer[refusal]
-	// complete is true once the app's whole answer has been passed on.
-	complete bool
-	// upgraded is the connection to the app once the app has switched
-	// protocols, as for a WebSocket, and nil otherwise.
-	upgraded *upgradedConn
-
-	// mu guards what follows. The timeouts run on goroutines of their
-	// own, and the transport starts and stops them, and notes the times
-	// below, from its own; once timersStopped is set, none of the timeouts
-	// acts any more.
-	mu                    sync.Mutex
-	timersStopped         bool
-	clientRequestTimer    *time.Timer
-	upstreamRequestTimer  *time.Timer
-	upstreamResponseTimer *time.Timer
-	// connected is when there was a connection to the app, requestSent
-	// when the app had been sent the whole request, and answerStarted
-	// when the first byte of its answer arrived.
-	connected     time.Time
-	requestSent   time.Time
-	answerStarted time.Time
-}
-
-// newRequest starts handling r: it works out the client from the TCP peer
-// and X-Forwarded-For, and goes on as startRequest does.
-func (h *handler) newRequest(w http.ResponseWriter, r *http.Request) *request {
-	peer := peerAddress(r)
-	trusted := h.config.TrustedProxies
-	client := clientAddress(peer, r.Header.Values("X-Forwarded-For"), trusted)
-
-	return h.startRequest(w, r, client, peer, isInside(peer, trusted))
-}
-
-// startRequest starts handling r from client, which came through peer: it
-// notes the time, counts the request as under way, and starts the log line
-// with what is known of the request. peerTrusted says whether to believe
-// the request's id and scheme, which r's headers give.
-func (h *handler) startRequest(
-	w http.ResponseWriter, r *http.Request, client, peer netip.Addr, peerTrusted bool,
-) *request {
-	h.metrics.RequestStarted()
-
-	start := time.Now()
-	forwardedFor := r.Header.Values("X-Forwarded-For")
-
-	rq := &request{
-		decision: decision{
-			client:     client,
-			requestURI: r.URL.RequestURI(),
-			line: requestlog.Line{
-				Time:             requestlog.FormatTime(start),
-				Instance:         h.config.InstanceName,
-				ClientIP:         client.String(),
-				Method:           r.Method,
-				Scheme:           scheme(r, peerTrusted),
-				Host:             r.Host,
-				Path:             rules.Path(r),
-				Query:            r.URL.RawQuery,
-				Protocol:         r.Proto,
-				Referer:          r.Referer(),
-				UserAgent:        r.UserAgent(),
-				RequestID:        requestID(r, peerTrusted),
-				PeerIP:           peer.String(),
-				ForwardedFor:     strings.Join(forwardedFor, ", "),
-				ClientGroup:      h.clientGroup(client).String(),
-				ContentType:      r.Header.Get("Content-Type"),
-				RequestHeaders:   requestHeaders(r, h.config.LogRequestHeaders),
-				HasAuthorization: len(r.Header.Values("Authorization")) > 0,
-				HasCookie:        len(r.Header.Values("Cookie")) > 0,
-				Action:           requestlog.ActionForward,
-			},
-		},
-		h:           h,
-		in:          r,
-		rc:          http.NewResponseController(w),
-		out:         &responseWriter{ResponseWriter: w},
-		peer:        peer,
-		peerTrusted: peerTrusted,
-		start:       start,
-	}
-
-	// A length of -1 is a body whose length was not announced.
-	if r.ContentLength > 0 {
-		rq.line.ContentLength = r.ContentLength
-	}
-
-	if r.Body != http.NoBody {
-		rq.body = &requestBody{body: limitBody(r.Body, h.config.RequestMaxBytes), rq: rq}
-	}
-
-	return rq
-}
-
-// requestHeaders returns the headers of r that names lists, by name in
-// lower case, each with its values joined by ", ". Authorization, Cookie
-// and Set-Cookie are never among them, whatever names says.
-func requestHeaders(r *http.Request, names []string) map[string]string {
-	headers := map[string]string{}
-
-	for _, name := range names {
-		switch name {
-		case "authorization", "cookie", "set-cookie":
-			continue
-		}
-
-		values := r.Header.Values(name)
-		if len(values) > 0 {
-			headers[name] = strings.Join(values, ", ")
-		}
-	}
-
-	return headers
-}
-
-// check is the one place where a request can be refused once its client
-// is known, before anything reaches the app, and before its body is read,
-// but for the part the Core Rule Set reads. It returns nil to let the
-// request through. The checks of checkClient come first, answered with
-// SWWAF_BAN_RESPONSE, 403 for a block rule or the Core Rule Set, or 431 for
-// servewaf's header limits, and then the size limit, so that a request the
-// rate limits count is counted even when it is refused for its size. In
-// observe mode a request checkClient refuses goes on to the size limit like
-// any other. A size or time limit the Core Rule Set's reading of the body
-// meets ends the request in either mode. ctx is the request's own context.
-func (rq *request) check(ctx context.Context) *refusal {
-	action := rq.checkClient(ctx)
-
-	refused := rq.refused.Load()
-	if refused != nil {
-		return refused
-	}
-
-	switch {
-	case action == "":
-	case rq.h.config.Observe:
-		// The log line names what enforce mode would have done.
-		rq.line.WouldAction = action
-	case action == requestlog.ActionRuleBlocked || action == requestlog.ActionWAFBlocked:
-		return &refusal{status: http.StatusForbidden, action: action}
-	case action == requestlog.ActionTooLarge:
-		return &refusal{status: http.StatusRequestHeaderFieldsTooLarge, action: action}
-	default:
-		return rq.banResponse(action)
-	}
-
-	maxBytes := rq.h.config.RequestMaxBytes
-	if maxBytes > 0 && rq.in.ContentLength > maxBytes {
-		return &refusal{
-			status: http.StatusRequestEntityTooLarge,
-			action: requestlog.ActionTooLarge,
-			limit:  "SWWAF_REQUEST_MAX_BYTES",
-		}
-	}
-
-	return nil
-}
-
-// checkClient runs the checks on the request's client, and returns the
-// action of the first that refuses the request, or "" when none does. A
-// client in SWWAF_ALLOW_NETS skips them, and is not looked up. For any
-// other client, SWWAF_DENY_NETS comes first, then a ban on its netblock,
-// so that a client either refuses is not looked up, then the lookup of
-// its AS number and country, then the country lists, then the blocklists,
-// then the CrowdSec decision list, which bans the client it lists, then
-// the DNSBL zones' verdicts, and then AbuseIPDB's score; a request any of
-// them refuses is not counted for the rate limits. Then come the
-// rate limits, unless the client is in SWWAF_RATE_LIMIT_EXEMPT_NETS or the
-// request's path is exempt under SWWAF_RATE_LIMIT_EXEMPT_PATHS, so that
-// every other request is counted, each of them by the client's limit
-// percentages, then SWWAF_TRAP_PATHS, then the rule files, then, in
-// servewaf, the header limits, and last the Core Rule Set. A request exempt
-// from the rate limits is exempt from the byte limits too. ctx is the
-// request's own context.
-func (rq *request) checkClient(ctx context.Context) string {
-	cfg := rq.h.config
-	if isInside(rq.client, cfg.AllowNets) {
-		return ""
-	}
-
-	now := rq.h.now()
-
-	if isInside(rq.client, cfg.DenyNets) {
-		return requestlog.ActionDenied
-	}
-
-	if rq.banned(now) {
-		return requestlog.ActionBanned
-	}
-
-	rq.lookUp(ctx, now)
-
-	// The lookup can wait for GeoJS, so the checks after it read the time
-	// again: a request counted at the time it arrived could be counted
-	// after a later one of its client's, which the rate limits would take
-	// for the clock set back.
-	now = rq.h.now()
-
-	if rq.countryDenied() {
-		return requestlog.ActionCountryDenied
-	}
-
-	if rq.blocklistDenied() {
-		return requestlog.ActionDenied
-	}
-
-	if rq.crowdSecBanned(now) {
-		return requestlog.ActionBanned
-	}
-
-	if rq.dnsblDenied(ctx) || rq.abuseIPDBDenied(ctx) {
-		return requestlog.ActionDenied
-	}
-
-	rq.counted = rq.countedByRateLimits()
-	if rq.counted {
-		rq.limitPercent, rq.bytesPercent = rq.limitPercentages()
-		rq.line.LimitPercent, rq.line.LimitPercentSetting = rq.limitPercent.logged()
-		rq.line.BytesPercent, rq.line.BytesPercentSetting = rq.bytesPercent.logged()
-	}
-
-	if rq.counted && rq.limitBroken(now) {
-		return requestlog.ActionRateLimited
-	}
-
-	if rq.trapPath(now) {
-		return requestlog.ActionBanned
-	}
-
-	action := rq.checkRules(now)
-	if action != "" {
-		return action
-	}
-
-	if rq.overHeaderLimits() {
-		return requestlog.ActionTooLarge
-	}
-
-	return rq.checkCoreRuleSet()
-}
-
-// countedByRateLimits reports whether the rate limits count the request: its
-// client is not in SWWAF_RATE_LIMIT_EXEMPT_NETS, and its path is not exempt
-// under SWWAF_RATE_LIMIT_EXEMPT_PATHS.
-func (rq *request) countedByRateLimits() bool {
-	cfg := rq.h.config
-
-	return !isInside(rq.client, cfg.RateLimitExemptNets) &&
-		!pathExempt(rq.in, cfg.RateLimitExemptPaths)
-}
-
-// pathExempt reports whether r is exempt under prefixes,
-// SWWAF_RATE_LIMIT_EXEMPT_PATHS or SWWAF_WAF_EXEMPT_PATHS: whether its
-// path as sent, the path the app receives, not percent-decoded, starts
-// with one of prefixes, so that /%61ssets/x is not under /assets/ for an
-// app whose router matches the path as received. A request whose decoded
-// path contains .. anywhere or a backslash, or whose path as sent holds an
-// encoded slash (%2F or %2f), never is, since an app may act on it as a
-// path outside every prefix: /assets/..%2Flogin as /login, or /assets%2Fx
-// as one path segment, as Go's router does.
-func pathExempt(r *http.Request, prefixes []string) bool {
-	decoded := r.URL.Path
-	sent := rules.Path(r)
-
-	if strings.Contains(decoded, "..") || strings.Contains(decoded, `\`) ||
-		strings.Contains(strings.ToLower(sent), "%2f") {
-		return false
-	}
-
-	return slices.ContainsFunc(prefixes, func(prefix string) bool {
-		return strings.HasPrefix(sent, prefix)
-	})
-}
-
-// forward passes the request to the app and the app's answer back. ctx
-// is the request's own context.
-func (rq *request) forward(ctx context.Context) {
-	ctx, cancel := context.WithCancel(ctx)
-	defer cancel()
-
-	rq.cancel = cancel
-	ctx = httptrace.WithClientTrace(ctx, &httptrace.ClientTrace{
-		GotConn:              rq.gotConn,
-		WroteRequest:         rq.wroteRequest,
-		GotFirstResponseByte: rq.gotFirstResponseByte,
-	})
-
-	out := rq.in.WithContext(ctx)
-	if rq.body != nil {
-		out.Body = rq.body
-	}
-
-	reverseProxy := &httputil.ReverseProxy{
-		Rewrite:        rq.rewrite,
-		Transport:      rq.h.transport,
-		FlushInterval:  flushAfterEachWrite,
-		ErrorLog:       rq.h.errorLog,
-		ModifyResponse: rq.modifyResponse,
-		ErrorHandler:   rq.answerError,
-	}
-
-	rq.startRequestTimers()
-	rq.upstreamStart = time.Now()
-	reverseProxy.ServeHTTP(rq.out, out)
-}
-
-// rewrite makes the request the app receives: the client's request,
-// unchanged, sent to SWWAF_UPSTREAM_URL, with the forwarded headers and
-// the request's id set, without any X-Client-ASN or X-Client-Country the
-// client sent, whatever SWWAF_ADD_LOOKUP_HEADERS says, and, while it is
-// set, with the client's AS number and country in them.
-func (rq *request) rewrite(pr *httputil.ProxyRequest) {
-	upstream := rq.h.config.UpstreamURL
-	pr.Out.URL.Scheme = upstream.Scheme
-	pr.Out.URL.Host = upstream.Host
-	// ReverseProxy drops query parameters it cannot parse; the app gets
-	// the query as the client sent it.
-	pr.Out.URL.RawQuery = pr.In.URL.RawQuery
-	// ReverseProxy sends the path URL.EscapedPath gives, which, for a path
-	// holding a character Go escapes, such as |, is the whole path decoded
-	// and escaped again, %2F turned into /. Opaque is sent as it is, so the
-	// app gets the path as the client sent it. Left out are a target that
-	// is no path, such as *, and a path starting with //, which Go would
-	// send in Opaque as a scheme and host.
-	path := rules.Path(pr.In)
-	if strings.HasPrefix(path, "/") && !strings.HasPrefix(path, "//") {
-		pr.Out.URL.Opaque = path
-	}
-
-	setForwardedHeaders(pr.In, pr.Out, rq.peer, rq.peerTrusted)
-	pr.Out.Header.Set(requestIDHeader, rq.line.RequestID)
-	pr.Out.Header.Del(asnHeader)
-	pr.Out.Header.Del(countryHeader)
-
-	if rq.h.config.AddLookupHeaders {
-		setLookupHeaders(pr.Out.Header, rq.line.ASN, rq.line.Country)
-	}
-}
-
-// modifyResponse looks at the app's answer before ReverseProxy passes it
-// on.
-func (rq *request) modifyResponse(res *http.Response) error {
-	rq.line.UpstreamStatus = res.StatusCode
-
-	if res.StatusCode == http.StatusSwitchingProtocols {
-		// An upgraded connection, such as a WebSocket, is not cut by the
-		// timeouts. ReverseProxy writes this answer straight to the
-		// connection it takes over, not through rq.out, and then copies
-		// what passes each way through res.Body, the connection to the app.
-		// It may still refuse the switch, as when the app's Upgrade is not
-		// the client's, so the status is noted only once it has taken over
-		// the connection, by rq.out's Hijack.
-		rq.stopTimers()
-		rq.line.Websocket = true
-
-		conn, ok := res.Body.(io.ReadWriteCloser)
-		if ok {
-			rq.upgraded = &upgradedConn{ReadWriteCloser: conn}
-			res.Body = rq.upgraded
-		}
-
-		return nil
-	}
-
-	maxBytes := rq.h.config.ResponseMaxBytes
-	if maxBytes > 0 && res.Body != http.NoBody && res.ContentLength > maxBytes {
-		rq.refuse(refusal{
-			status: http.StatusBadGateway,
-			action: requestlog.ActionTooLarge,
-			limit:  "SWWAF_RESPONSE_MAX_BYTES",
-		})
-
-		return errResponseTooLarge
-	}
-
-	// Go's server adds a Content-Type it guesses from the body to a
-	// response whose headers have no Content-Type key. The key with no
-	// value sends none, as the app sent none.
-	if res.Header.Get("Content-Type") == "" {
-		rq.out.Header()["Content-Type"] = nil
-	}
-
-	res.Body = &responseBody{body: limitBody(res.Body, maxBytes), rq: rq}
-	rq.startClientResponseTimeout()
-
-	return nil
-}
-
-// answerError is ReverseProxy's ErrorHandler: the request could not be
-// passed to the app, or the app's answer cannot be passed on.
-func (rq *request) answerError(_ http.ResponseWriter, _ *http.Request, err error) {
-	if rq.upgraded != nil {
-		// The app switched protocols, but the switch was not passed on,
-		// and ReverseProxy leaves the app's connection open when it
-		// refuses it.
-		_ = rq.upgraded.Close()
-	}
-
-	refused := rq.refused.Load()
-	if refused == nil {
-		if rq.in.Context().Err() != nil {
-			return // the client has gone, and there is no one to answer
-		}
-
-		rq.h.processLog.Warn("request to the app failed", "error", err.Error())
-
-		refused = &refusal{
-			status: http.StatusBadGateway,
-			action: requestlog.ActionUpstreamError,
-		}
-	}
-
-	rq.answer(*refused)
-}
-
-// answer sends smallwebwaf's own answer, unless the response has already
-// started, and records the refusal for the log line.
-func (rq *request) answer(r refusal) {
-	rq.refused.CompareAndSwap(nil, &r)
-
-	if rq.out.status != 0 {
-		return // too late to answer: the connection can only be cut
-	}
-
-	if r.status == 0 {
-		// SWWAF_BAN_RESPONSE is close. This panic has Go's server close
-		// the connection without an answer, and log nothing; the log line
-		// is still written as the handler returns.
-		panic(http.ErrAbortHandler)
-	}
-
-	// A client found too slow is read no more; any other may go on
-	// sending until its time is up, so that Go's server can read the
-	// rest of the body and end the request cleanly.
-	deadline := rq.clientRequestDeadline()
-	if r.status == http.StatusRequestTimeout {
-		deadline = time.Now()
-	}
-
-	rq.stopReadingBody(deadline)
-
-	timeout := rq.h.config.ClientResponseTimeout
-	if timeout > 0 {
-		_ = rq.rc.SetWriteDeadline(time.Now().Add(timeout))
-	}
-
-	http.Error(rq.out, http.StatusText(r.status), r.status)
-}
-
-// refuse records r, unless an earlier refusal was, and ends the request
-// to the app, if one was made: smallwebwaf reads the body of a request
-// it answers itself too.
-func (rq *request) refuse(r refusal) {
-	rq.refused.CompareAndSwap(nil, &r)
-
-	if rq.cancel != nil {
-		rq.cancel()
-	}
-}
-
-// finish ends the request's timeouts, counts it in the metrics and writes
-// its log line.
-func (rq *request) finish() {
-	rq.stopTimers()
-
-	refused := rq.refused.Load()
-	if refused == nil {
-		rq.stopReadingBody(rq.clientRequestDeadline())
-	}
-
-	line := &rq.line
-	line.Status = rq.out.status
-	line.ResponseBytes = rq.out.bytes
-	header := rq.out.Header()
-	line.ResponseContentType = header.Get("Content-Type")
-	line.CacheControl = header.Get("Cache-Control")
-	line.Location = header.Get("Location")
-	line.RequestBytes = rq.requestBytes()
-
-	// limit is the setting whose size or time limit the request passed.
-	var limit string
-
-	switch {
-	case refused != nil:
-		line.Action = refused.action
-		limit = refused.limit
-	case errors.Is(rq.out.err, os.ErrDeadlineExceeded):
-		// The client took longer than SWWAF_CLIENT_RESPONSE_TIMEOUT to
-		// take the response.
-		line.Action = requestlog.ActionTimedOut
-		limit = "SWWAF_CLIENT_RESPONSE_TIMEOUT"
-	case !rq.complete && (rq.out.err != nil || rq.in.Context().Err() != nil):
-		line.Aborted = true
-	}
-
-	now := time.Now()
-	duration := now.Sub(rq.start)
-	line.DurationTotal = requestlog.Milliseconds(duration)
-	line.DurationChecks = timing(rq.start, rq.checked)
-
-	var upstreamDuration time.Duration
-
-	if !rq.upstreamStart.IsZero() {
-		upstreamDuration = now.Sub(rq.upstreamStart)
-		line.DurationUpstreamTotal = new(requestlog.Milliseconds(upstreamDuration))
-
-		rq.mu.Lock()
-		line.DurationUpstreamConnect = timing(rq.upstreamStart, rq.connected)
-		line.DurationUpstreamFirstByte = timing(rq.upstreamStart, rq.answerStarted)
-		rq.mu.Unlock()
-	}
-
-	// Counted before the log line is written, so that the metrics count
-	// every request whose line is out. An allowed request is the exception:
-	// its report gives the status, bytes and times the metrics count.
-	if rq.allowed {
-		rq.h.metrics.RequestAllowed()
-	} else {
-		rq.h.metrics.RequestEnded(line, limit, duration, upstreamDuration)
-	}
-
-	rq.writeLine()
-}
-
-// writeLine writes the request's log line.
-func (rq *request) writeLine() {
-	err := requestlog.Write(rq.h.requestLog, &rq.line)
-	if err != nil {
-		rq.h.processLog.Error("writing the request log failed", "error", err.Error())
-	}
-}
-
-// timing is the time from start to end in milliseconds, for one of the
-// log line's timings, or nil when end is zero: what it times never
-// happened.
-func timing(start, end time.Time) *float64 {
-	if end.IsZero() {
-		return nil
-	}
-
-	return new(requestlog.Milliseconds(end.Sub(start)))
-}
-
-// addToHistory adds the request, which has ended, to its client's
-// history, and counts its offences in the metrics, and then the lookup's
-// answer about the client, as answerAtTheEnd gives it, to that history and
-// to the notes of the bans on its netblock: an answer may have come
-// before either was there, and one from GeoJS that comes later is added
-// when it comes.
-func (rq *request) addToHistory() {
-	forwarded := !rq.upstreamStart.IsZero()
-	request := ratelimit.Request{
-		Forwarded:     forwarded,
-		Refused:       !forwarded && rq.refused.Load() != nil,
-		Status:        rq.out.status,
-		RequestBytes:  rq.requestBytes(),
-		ResponseBytes: rq.out.bytes,
-		BrokeLimit:    rq.line.Offence == requestlog.OffenceLimit,
-		Attack:        rq.attack,
-		RuleBlocked:   rq.ruleBlocked,
-		WAFBlocked:    rq.wafBlocked,
-		TokenRefused:  rq.tokenRefused,
-	}
-
-	rq.h.limiter.AddToHistory(rq.h.clientGroup(rq.client), rq.h.now(), request)
-	rq.h.metrics.Offences(request)
-
-	answer, found := rq.answerAtTheEnd()
-	if found {
-		rq.h.addLookup(answer)
-	}
-}
-
-// countAnomalies counts the request, which has ended, and its bytes, as
-// countedBytes gives them, for the anomaly thresholds, whatever was done
-// with it: a request refused, one from a client in SWWAF_ALLOW_NETS or
-// SWWAF_RATE_LIMIT_EXEMPT_NETS, and one for a path in
-// SWWAF_RATE_LIMIT_EXEMPT_PATHS are counted too. It is counted for its
-// client's AS number when answerAtTheEnd gives one. With every anomaly
-// threshold off, the default, it does nothing.
-func (rq *request) countAnomalies() {
-	if !anomalyThresholdsSet(rq.h.config) {
-		return
-	}
-
-	answer, _ := rq.answerAtTheEnd()
-
-	rq.h.anomalies.Count(rq.h.now(), anomaly.Request{
-		Host:        rq.site,
-		Client:      rq.client,
-		ClientGroup: rq.h.clientGroup(rq.client),
-		ASN:         answer.ASN,
-		ASName:      answer.ASName,
-		Country:     answer.Country,
-		Bytes:       rq.countedBytes(),
-	})
-}
-
-// anomalyThresholdsSet reports whether any anomaly threshold is set.
-func anomalyThresholdsSet(cfg *config.Config) bool {
-	off := anomaly.Thresholds{}
-
-	return cfg.AnomalyClient != off || cfg.AnomalyNet != off || cfg.AnomalyASN != off ||
-		cfg.AnomalyTotal != off || cfg.AnomalyWatch != off
-}
-
-// answerAtTheEnd returns, for a client that was looked up, the lookup's
-// answer about it as the request ends, and whether there is one: the
-// lookup database's, which was there at once, or the one GeoJS has given
-// by then, which a request does not wait for unless a setting needs it.
-func (rq *request) answerAtTheEnd() (lookup.Answer, bool) {
-	if !rq.lookedUp {
-		return lookup.Answer{}, false
-	}
-
-	if rq.h.config.LookupSource == "file" {
-		return rq.lookupAnswer, true
-	}
-
-	return rq.h.geojs.Kept(rq.h.clientGroup(rq.client))
-}
-
-// requestBytes is how many bytes of the request's body have been read.
-func (rq *request) requestBytes() int64 {
-	if rq.body == nil {
-		return 0
-	}
-
-	return rq.body.bytes.Load()
-}
-
-// clientRequestDeadline is when the client must have sent its whole
-// request, or zero when SWWAF_CLIENT_REQUEST_TIMEOUT is off.
-func (rq *request) clientRequestDeadline() time.Time {
-	timeout := rq.h.config.ClientRequestTimeout
-	if timeout == 0 {
-		return time.Time{}
-	}
-
-	return rq.start.Add(timeout)
-}
-
-// stopReadingBody ends, at deadline, the reading of a client body that has
-// not arrived whole: Go's server then reads no more of it, and closes the
-// connection after the answer.
-func (rq *request) stopReadingBody(deadline time.Time) {
-	if rq.body == nil || rq.body.received.Load() {
-		return
-	}
-
-	_ = rq.rc.SetReadDeadline(deadline)
-}
-
-// startRequestTimers starts the timeouts that run while the request goes
-// to the app: SWWAF_CLIENT_REQUEST_TIMEOUT until the client has sent its
-// whole body, and SWWAF_UPSTREAM_REQUEST_TIMEOUT until the app has been
-// sent the whole request.
-func (rq *request) startRequestTimers() {
-	rq.mu.Lock()
-	defer rq.mu.Unlock()
-
-	if rq.body != nil && rq.h.config.ClientRequestTimeout > 0 {
-		rq.clientRequestTimer = time.AfterFunc(
-			time.Until(rq.clientRequestDeadline()), func() {
-				rq.requestTimedOut("SWWAF_CLIENT_REQUEST_TIMEOUT")
-			})
-	}
-
-	timeout := rq.h.config.UpstreamRequestTimeout
-	if timeout > 0 {
-		rq.upstreamRequestTimer = time.AfterFunc(timeout, func() {
-			rq.requestTimedOut("SWWAF_UPSTREAM_REQUEST_TIMEOUT")
-		})
-	}
-}
-
-// requestTimedOut is called when limit, SWWAF_CLIENT_REQUEST_TIMEOUT or
-// SWWAF_UPSTREAM_REQUEST_TIMEOUT, runs out while the request is still on
-// its way to the app. The answer names the side smallwebwaf was waiting
-// on at that moment: 408 when it was waiting for the client to send more
-// of its body, 504 when it was waiting for the app to be reached or to
-// take what it had.
-func (rq *request) requestTimedOut(limit string) {
-	rq.mu.Lock()
-	defer rq.mu.Unlock()
-
-	if rq.timersStopped {
-		return
-	}
-
-	if rq.body == nil || !rq.body.waiting.Load() {
-		// Once the app has answered, the transport, ReverseProxy and Go's
-		// server each close the client's body, and closing it reads what
-		// is left of a body under 256 KiB without requestBody.Read, so
-		// waiting is false while that read waits for the client. That
-		// read ends now, before refuse: should smallwebwaf still answer
-		// itself, answer then sets the deadline it gives its own answers.
-		if !rq.answerStarted.IsZero() {
-			rq.stopReadingBody(time.Now())
-		}
-
-		rq.refuse(refusal{
-			status: http.StatusGatewayTimeout,
-			action: requestlog.ActionTimedOut,
-			limit:  limit,
-		})
-
-		return
-	}
-
-	rq.refuse(refusal{
-		status: http.StatusRequestTimeout,
-		action: requestlog.ActionTimedOut,
-		limit:  limit,
-	})
-	// The transport gives up on the app only once its Read of the
-	// client's body returns, so that Read is ended now. The lock keeps
-	// this from reaching the connection after the request is handled.
-	_ = rq.rc.SetReadDeadline(time.Now())
-}
-
-// bodyReceived is called once the client has sent its whole body.
-func (rq *request) bodyReceived() {
-	rq.mu.Lock()
-	defer rq.mu.Unlock()
-
-	stopTimer(rq.clientRequestTimer)
-}
-
-// gotConn is called once there is a connection to the app, a new one or
-// one kept open from an earlier request.
-func (rq *request) gotConn(httptrace.GotConnInfo) {
-	rq.mu.Lock()
-	defer rq.mu.Unlock()
-
-	rq.connected = time.Now()
-}
-
-// gotFirstResponseByte is called once the first byte of the app's answer
-// has arrived.
-func (rq *request) gotFirstResponseByte() {
-	rq.mu.Lock()
-	defer rq.mu.Unlock()
-
-	rq.answerStarted = time.Now()
-}
-
-// wroteRequest is called once the app has been sent the whole request:
-// the request timeouts end and SWWAF_UPSTREAM_RESPONSE_TIMEOUT starts.
-func (rq *request) wroteRequest(info httptrace.WroteRequestInfo) {
-	if info.Err != nil {
-		return // the transport gives up, or tries again
-	}
-
-	rq.mu.Lock()
-	defer rq.mu.Unlock()
-
-	if rq.timersStopped {
-		return
-	}
-
-	stopTimer(rq.clientRequestTimer)
-	stopTimer(rq.upstreamRequestTimer)
-	rq.requestSent = time.Now()
-
-	timeout := rq.h.config.UpstreamResponseTimeout
-	if timeout > 0 {
-		rq.upstreamResponseTimer = time.AfterFunc(timeout, rq.responseTimedOut)
-	}
-}
-
-// responseTimedOut is called when SWWAF_UPSTREAM_RESPONSE_TIMEOUT runs out
-// before the app has sent its whole answer.
-func (rq *request) responseTimedOut() {
-	rq.mu.Lock()
-	defer rq.mu.Unlock()
-
-	if !rq.timersStopped {
-		rq.refuse(refusal{
-			status: http.StatusGatewayTimeout,
-			action: requestlog.ActionTimedOut,
-			limit:  "SWWAF_UPSTREAM_RESPONSE_TIMEOUT",
-		})
-	}
-}
-
-// responseReceived is called once the app has sent its whole answer. An
-// app may answer before the client has sent its whole body, as with a 404
-// it sends without reading it. The timeouts then run on: until the
-// transport's read of the body returns, Go's server cannot send the
-// answer, and SWWAF_CLIENT_REQUEST_TIMEOUT is what ends that read for a
-// client that stops sending.
-func (rq *request) responseReceived() {
-	rq.complete = true
-
-	if rq.body != nil && !rq.body.received.Load() {
-		return
-	}
-
-	rq.stopTimers()
-}
-
-// startClientResponseTimeout sets SWWAF_CLIENT_RESPONSE_TIMEOUT on the
-// connection to the client: the response must reach the client within it
-// of the end of the request, or of now if the app answers before it has
-// the whole request.
-func (rq *request) startClientResponseTimeout() {
-	timeout := rq.h.config.ClientResponseTimeout
-	if timeout == 0 {
-		return
-	}
-
-	from := rq.sentAt()
-	if from.IsZero() {
-		from = time.Now()
-	}
-
-	_ = rq.rc.SetWriteDeadline(from.Add(timeout))
-}
-
-// sentAt is when the app had been sent the whole request, or zero.
-func (rq *request) sentAt() time.Time {
-	rq.mu.Lock()
-	defer rq.mu.Unlock()
-
-	return rq.requestSent
-}
-
-// stopTimers stops the request's timeouts and keeps any from starting
-// later: the app's answer is complete, the connection upgraded, or the
-// request handled.
-func (rq *request) stopTimers() {
-	rq.mu.Lock()
-	defer rq.mu.Unlock()
-
-	rq.timersStopped = true
-	stopTimer(rq.clientRequestTimer)
-	stopTimer(rq.upstreamRequestTimer)
-	stopTimer(rq.upstreamResponseTimer)
-}
-
-// stopTimer stops t, which is nil when its timeout is off.
-func stopTimer(t *time.Timer) {
-	if t != nil {
-		t.Stop()
-	}
-}

internal/proxy/request_internal_test.go

@@ -1,55 +0,0 @@
-package proxy
-
-import (
-	"io"
-	"net/http"
-	"net/http/httptest"
-	"testing"
-
-	"sneak.berlin/go/smallwebwaf/internal/config"
-)
-
-func TestAnAnswerWithoutAContentTypeGetsNone(t *testing.T) {
-	t.Parallel()
-
-	srv := httptest.NewServer(http.HandlerFunc(
-		func(w http.ResponseWriter, _ *http.Request) {
-			rq := &request{
-				h:   &handler{config: &config.Config{}},
-				out: &responseWriter{ResponseWriter: w},
-			}
-			app := &http.Response{
-				StatusCode: http.StatusOK,
-				Header:     http.Header{},
-				Body:       http.NoBody,
-			}
-
-			err := rq.modifyResponse(app)
-			if err != nil {
-				t.Errorf("modifyResponse: %v", err)
-			}
-
-			// The headers go out with this, the first part of the body,
-			// which Go's server would guess a Content-Type from.
-			_, _ = io.WriteString(w, "<!doctype html><title>page</title>")
-		}))
-	t.Cleanup(srv.Close)
-
-	req, err := http.NewRequestWithContext(t.Context(), http.MethodGet, srv.URL,
-		http.NoBody)
-	if err != nil {
-		t.Fatalf("new request: %v", err)
-	}
-
-	res, err := srv.Client().Do(req)
-	if err != nil {
-		t.Fatalf("get: %v", err)
-	}
-
-	_ = res.Body.Close()
-
-	if res.Header.Values("Content-Type") != nil {
-		t.Errorf("client got Content-Type %q, want none",
-			res.Header.Get("Content-Type"))
-	}
-}

internal/proxy/rules.go

@@ -1,64 +0,0 @@
-package proxy
-
-import (
-	"slices"
-	"time"
-
-	"sneak.berlin/go/smallwebwaf/internal/bans"
-	"sneak.berlin/go/smallwebwaf/internal/requestlog"
-	"sneak.berlin/go/smallwebwaf/internal/rules"
-)
-
-// trapPath reports whether the request asks for a path in
-// SWWAF_TRAP_PATHS: its path as a path rule sees it, without the query,
-// as sent or once percent-decoded, is one of them. Such a request is a
-// clear sign of attack, as a ban rule's match is: it bans the client's
-// netblock, or in observe mode raises the alert for the ban it would have
-// made. The ban's notes give the path as sent.
-func (rq *request) trapPath(now time.Time) bool {
-	path := rules.Path(rq.in)
-	if !slices.Contains(rq.h.config.TrapPaths, path) &&
-		!slices.Contains(rq.h.config.TrapPaths, rules.DecodeOnce(path)) {
-		return false
-	}
-
-	rq.attack = true
-	rq.banForAttack(now, bans.Notes{TrapPath: path})
-
-	return true
-}
-
-// checkRules checks the request against the rules of the rule files at
-// now, notes the ids of those it matches in the log line, and returns the
-// action of the rule that refuses it, ActionRuleBlocked for a block rule
-// and ActionBanned for a ban rule, or "" when none does. A ban rule bans
-// the client's netblock for a clear sign of attack, or in observe mode
-// raises the alert for the ban it would have made. Either rule's match
-// is noted as an offence, for the client's history.
-func (rq *request) checkRules(now time.Time) string {
-	matched := rq.h.rules.Match(rq.in)
-
-	for _, rule := range matched {
-		rq.line.RuleIDs = append(rq.line.RuleIDs, rule.ID)
-		rq.h.metrics.RuleMatched(rule.ID, rule.Action)
-	}
-
-	if len(matched) == 0 {
-		return ""
-	}
-
-	// Only the last rule matched can refuse the request.
-	switch last := matched[len(matched)-1]; last.Action {
-	case rules.ActionBlock:
-		rq.ruleBlocked = true
-
-		return requestlog.ActionRuleBlocked
-	case rules.ActionBan:
-		rq.attack = true
-		rq.banForAttack(now, bans.Notes{RuleID: last.ID, Target: last.Target})
-
-		return requestlog.ActionBanned
-	default:
-		return ""
-	}
-}

internal/proxy/timeouts_test.go

@@ -1,453 +0,0 @@
-package proxy_test
-
-import (
-	"errors"
-	"io"
-	"net"
-	"net/http"
-	"net/http/httptest"
-	"strconv"
-	"strings"
-	"sync"
-	"sync/atomic"
-	"testing"
-	"time"
-
-	"sneak.berlin/go/smallwebwaf/internal/requestlog"
-)
-
-// largeBodySize is more than the connections between the client,
-// smallwebwaf and the app can hold while nobody reads, so that a sender
-// soon waits.
-const largeBodySize = 64 << 20
-
-// writeSize is how much a test sender writes at a time.
-const writeSize = 32 << 10
-
-func TestRequestTimeouts(t *testing.T) {
-	t.Parallel()
-
-	for _, tc := range []struct {
-		name string
-		// limit is the setting set to shortTimeout, which runs out; long
-		// is one set to longTimeoutSetting, which does not, or "".
-		limit, long string
-		// appTakesNothing has the app never read, while the client sends
-		// as fast as it can; otherwise the app reads, and the client
-		// stops sending halfway.
-		appTakesNothing bool
-		want            int
-	}{
-		{
-			name:  "client request timeout, waiting on the client",
-			limit: clientRequestTimeout,
-			want:  http.StatusRequestTimeout,
-		},
-		{
-			name:  "upstream request timeout, waiting on the client",
-			limit: upstreamRequestTimeout,
-			long:  clientRequestTimeout,
-			want:  http.StatusRequestTimeout,
-		},
-		{
-			name:            "upstream request timeout, waiting on the app",
-			limit:           upstreamRequestTimeout,
-			appTakesNothing: true,
-			want:            http.StatusGatewayTimeout,
-		},
-		{
-			name:            "client request timeout, waiting on the app",
-			limit:           clientRequestTimeout,
-			long:            upstreamRequestTimeout,
-			appTakesNothing: true,
-			want:            http.StatusGatewayTimeout,
-		},
-	} {
-		t.Run(tc.name, func(t *testing.T) {
-			t.Parallel()
-
-			var (
-				app         *httptest.Server
-				appURL      string
-				sendRequest func(*testing.T, string) net.Conn
-				appGotBody  atomic.Bool
-			)
-
-			if tc.appTakesNothing {
-				appURL, sendRequest = startAppThatTakesNothing(t), sendLargeBody
-			} else {
-				app = startApp(t, func(_ http.ResponseWriter, r *http.Request) {
-					n, _ := io.Copy(io.Discard, r.Body)
-					appGotBody.Store(n > 0)
-				})
-				appURL, sendRequest = app.URL, sendPartOfBody
-			}
-
-			env := map[string]string{tc.limit: shortTimeoutSetting, metricsToken: token}
-			if tc.long != "" {
-				env[tc.long] = longTimeoutSetting
-			}
-
-			addr, out := startProxy(t, appURL, env)
-			start := time.Now()
-			got := readResponse(t, sendRequest(t, addr))
-			wantTimedOut(t, start)
-
-			want := tc.want
-
-			if app != nil {
-				// Close returns once the app has finished with the request.
-				app.Close()
-
-				// Until some of the body has reached the app, smallwebwaf
-				// waits on the app, and SPEC.md asks for 504; the timeout
-				// runs out then only if the test process is held up.
-				if !appGotBody.Load() {
-					want = http.StatusGatewayTimeout
-				}
-			}
-
-			wantStatus(t, got, want)
-			wantLine(t, out.requestLine(t), want, requestlog.ActionTimedOut)
-			wantLimitHits(t, addr, tc.limit, 1)
-		})
-	}
-}
-
-// startAppThatTakesNothing starts an app that accepts connections and
-// never reads from them, and returns its URL.
-func startAppThatTakesNothing(t *testing.T) string {
-	t.Helper()
-
-	listener, err := (&net.ListenConfig{}).Listen(t.Context(), "tcp", localhost+":0")
-	if err != nil {
-		t.Fatalf("listen: %v", err)
-	}
-
-	var (
-		mu   sync.Mutex
-		held []net.Conn
-	)
-
-	hold := func(conn net.Conn) {
-		mu.Lock()
-		defer mu.Unlock()
-
-		held = append(held, conn)
-	}
-
-	go func() {
-		for {
-			conn, err := listener.Accept()
-			if err != nil {
-				return
-			}
-
-			hold(conn)
-		}
-	}()
-
-	t.Cleanup(func() {
-		_ = listener.Close()
-
-		mu.Lock()
-		defer mu.Unlock()
-
-		for _, conn := range held {
-			_ = conn.Close()
-		}
-	})
-
-	return "http://" + listener.Addr().String()
-}
-
-// sendPartOfBody sends a request that announces a large body, and only
-// the first bytes of it.
-func sendPartOfBody(t *testing.T, addr string) net.Conn {
-	t.Helper()
-
-	conn := dial(t, addr)
-	send(t, conn, "POST /upload HTTP/1.1\r\nHost: app\r\nContent-Length: "+
-		strconv.Itoa(largeBodySize)+"\r\n\r\nthe first bytes")
-
-	return conn
-}
-
-// sendLargeBody sends a request with a large body, as fast as smallwebwaf
-// takes it, from a goroutine of its own.
-func sendLargeBody(t *testing.T, addr string) net.Conn {
-	t.Helper()
-
-	conn := dial(t, addr)
-	send(t, conn, "POST /upload HTTP/1.1\r\nHost: app\r\nContent-Length: "+
-		strconv.Itoa(largeBodySize)+"\r\n\r\n")
-
-	go func() {
-		chunk := make([]byte, writeSize)
-		for range largeBodySize / writeSize {
-			_, err := conn.Write(chunk)
-			if err != nil {
-				return
-			}
-		}
-	}()
-
-	return conn
-}
-
-func TestClientStopsSendingAfterTheAppHasAnswered(t *testing.T) {
-	t.Parallel()
-
-	// answeredAt is when the app answered, or nil if the bytes the client
-	// sent never reached it.
-	var answeredAt atomic.Pointer[time.Time]
-
-	// The app answers without reading the whole body, as an app does for
-	// a path it does not serve, and only once smallwebwaf waits for the
-	// rest of it: the app takes the bytes the client sent, and then waits
-	// half the timeout, far longer than smallwebwaf takes to go on to
-	// wait.
-	app := startApp(t, func(w http.ResponseWriter, r *http.Request) {
-		_, err := io.ReadFull(r.Body, make([]byte, len("the first bytes")))
-		if err != nil {
-			return
-		}
-
-		time.Sleep(shortTimeout / 2)
-		answeredAt.Store(new(time.Now()))
-		http.NotFound(w, r)
-	})
-	addr, out := startProxy(t, app.URL, map[string]string{
-		clientRequestTimeout: shortTimeoutSetting,
-		metricsToken:         token,
-	})
-
-	start := time.Now()
-	got := readResponse(t, sendPartOfBody(t, addr))
-	wantTimedOut(t, start)
-
-	// Close returns once the app has finished with the request.
-	app.Close()
-
-	// The app's answer came before the time ran out, so the client is
-	// sent that answer, not smallwebwaf's 408. Only a hold-up of the test
-	// process can make it come later, and SPEC.md then asks for 408, as
-	// smallwebwaf was waiting for the client, or for 504 if the bytes the
-	// client sent had not reached the app.
-	at := answeredAt.Load()
-	want := http.StatusNotFound
-
-	switch {
-	case at == nil:
-		want = http.StatusGatewayTimeout
-	case at.Sub(start) >= shortTimeout:
-		want = http.StatusRequestTimeout
-	}
-
-	wantStatus(t, got, want)
-	wantLine(t, out.requestLine(t), want, requestlog.ActionTimedOut)
-	wantLimitHits(t, addr, clientRequestTimeout, 1)
-}
-
-func TestClientStopsSendingWithLittleOfItsBodyLeft(t *testing.T) {
-	t.Parallel()
-
-	for _, tc := range []struct {
-		name string
-		// limit is the setting set to shortTimeout, which runs out, and
-		// clientTimeout what SWWAF_CLIENT_REQUEST_TIMEOUT is set to when it
-		// is not limit.
-		limit, clientTimeout string
-	}{
-		{
-			name:  "client request timeout",
-			limit: clientRequestTimeout,
-		},
-		{
-			name:          "upstream request timeout, client request timeout off",
-			limit:         upstreamRequestTimeout,
-			clientTimeout: off,
-		},
-		{
-			name:          "upstream request timeout, client request timeout longer",
-			limit:         upstreamRequestTimeout,
-			clientTimeout: longTimeoutSetting,
-		},
-	} {
-		t.Run(tc.name, func(t *testing.T) {
-			t.Parallel()
-
-			// appClosed is closed once smallwebwaf has closed its
-			// connection to the app, which it does once it has the app's
-			// answer.
-			appClosed := make(chan struct{})
-
-			// The app answers without reading the rest of the body, and
-			// says it closes the connection, only once smallwebwaf waits
-			// for the client to send more: it takes the bytes the client
-			// sent, and then waits half the timeout, far longer than
-			// smallwebwaf takes to go on to wait.
-			app := startApp(t, func(w http.ResponseWriter, _ *http.Request) {
-				conn, buf, err := http.NewResponseController(w).Hijack()
-				if err != nil {
-					return
-				}
-
-				_, _ = io.ReadFull(buf.Reader, make([]byte, len("the first bytes")))
-
-				time.Sleep(shortTimeout / 2)
-
-				_, _ = buf.WriteString("HTTP/1.1 404 Not Found\r\n" +
-					"Content-Length: 0\r\nConnection: close\r\n\r\n")
-				_ = buf.Flush()
-				_, _ = io.Copy(io.Discard, buf.Reader)
-				_ = conn.Close()
-
-				close(appClosed)
-			})
-
-			env := map[string]string{tc.limit: shortTimeoutSetting, metricsToken: token}
-			if tc.clientTimeout != "" {
-				env[clientRequestTimeout] = tc.clientTimeout
-			}
-
-			addr, out := startProxy(t, app.URL, env)
-
-			// Less than 256 KiB of the body is left after the first bytes,
-			// little enough for Go's server in smallwebwaf to read the rest
-			// itself before it sends the app's answer.
-			start := time.Now()
-			conn := dial(t, addr)
-			send(t, conn, "POST /upload HTTP/1.1\r\nHost: app\r\nContent-Length: 200000\r\n\r\n"+
-				"the first bytes")
-
-			select {
-			case <-appClosed:
-			case <-time.After(waitLimit):
-				t.Fatal("smallwebwaf did not close its connection to the app")
-			}
-
-			// More of the body, which can no longer go to the app, and then
-			// nothing.
-			send(t, conn, strings.Repeat("x", 8<<10))
-
-			got := readResponse(t, conn)
-			wantTimedOut(t, start)
-			wantStatus(t, got, http.StatusNotFound)
-			wantLine(t, out.requestLine(t), http.StatusNotFound, requestlog.ActionTimedOut)
-			wantLimitHits(t, addr, tc.limit, 1)
-		})
-	}
-}
-
-func TestAppTooSlowToAnswer(t *testing.T) {
-	t.Parallel()
-
-	app := startApp(t, func(_ http.ResponseWriter, r *http.Request) {
-		<-r.Context().Done()
-	})
-	addr, out := startProxy(t, app.URL, map[string]string{
-		upstreamResponseTimeout: shortTimeoutSetting,
-		metricsToken:            token,
-	})
-
-	start := time.Now()
-
-	wantStatus(t, get(t, addr, "/slow"), http.StatusGatewayTimeout)
-	wantTimedOut(t, start)
-
-	line := out.requestLine(t)
-	wantLine(t, line, http.StatusGatewayTimeout, requestlog.ActionTimedOut)
-
-	_, answered := line.fields["upstream_status"]
-	if answered {
-		t.Errorf("log line has upstream_status %v for an app that never answered",
-			line.fields["upstream_status"])
-	}
-
-	wantLimitHits(t, addr, upstreamResponseTimeout, 1)
-}
-
-func TestAppTooSlowToFinishItsAnswer(t *testing.T) {
-	t.Parallel()
-
-	app := startApp(t, func(w http.ResponseWriter, r *http.Request) {
-		_, _ = io.WriteString(w, "the first part")
-		_ = http.NewResponseController(w).Flush()
-
-		<-r.Context().Done()
-	})
-	addr, out := startProxy(t, app.URL, map[string]string{
-		upstreamResponseTimeout: shortTimeoutSetting,
-	})
-
-	start := time.Now()
-	got := get(t, addr, "/slow")
-	wantStatus(t, got, http.StatusOK)
-
-	if string(got.body) != "the first part" || !errors.Is(got.err, io.ErrUnexpectedEOF) {
-		t.Errorf("client read %q (%v), want the first part cut off", got.body, got.err)
-	}
-
-	wantTimedOut(t, start)
-
-	line := out.requestLine(t)
-	wantLine(t, line, http.StatusOK, requestlog.ActionTimedOut)
-
-	if line.UpstreamStatus != http.StatusOK {
-		t.Errorf("log line has upstream_status %d, want %d",
-			line.UpstreamStatus, http.StatusOK)
-	}
-}
-
-func TestClientTooSlowToTakeTheAnswer(t *testing.T) {
-	t.Parallel()
-
-	app := startApp(t, func(w http.ResponseWriter, _ *http.Request) {
-		chunk := make([]byte, writeSize)
-		for range largeBodySize / writeSize {
-			_, err := w.Write(chunk)
-			if err != nil {
-				return
-			}
-		}
-	})
-	addr, out := startProxy(t, app.URL, map[string]string{
-		clientResponseTimeout: shortTimeoutSetting,
-		metricsToken:          token,
-	})
-
-	start := time.Now()
-
-	// The client asks, and never reads the answer.
-	conn := dial(t, addr)
-	send(t, conn, "GET /large HTTP/1.1\r\nHost: app\r\n\r\n")
-
-	line := out.requestLine(t)
-	wantTimedOut(t, start)
-	wantLine(t, line, http.StatusOK, requestlog.ActionTimedOut)
-	wantLimitHits(t, addr, clientResponseTimeout, 1)
-}
-
-func TestClosesAnIdleConnection(t *testing.T) {
-	t.Parallel()
-
-	app := startApp(t, func(http.ResponseWriter, *http.Request) {})
-	addr, _ := startProxy(t, app.URL, map[string]string{
-		clientIdleTimeout: shortTimeoutSetting,
-	})
-
-	// The idle time starts once the answer is sent, so after start.
-	start := time.Now()
-	conn := dial(t, addr)
-	send(t, conn, "GET / HTTP/1.1\r\nHost: app\r\n\r\n")
-	wantStatus(t, readResponse(t, conn), http.StatusOK)
-
-	// The read deadline readResponse set still bounds this read.
-	_, err := conn.Read(make([]byte, 1))
-	if !errors.Is(err, io.EOF) {
-		t.Fatalf("read on the idle connection: %v, want it closed", err)
-	}
-
-	wantTimedOut(t, start)
-}

internal/ratelimit/history_test.go

@@ -23,8 +23,8 @@ func TestHistoryKeepsEveryRequest(t *testing.T) {
 		{Forwarded: true, Status: 502, ResponseBytes: 12},
 		// Closed without an answer: refused, and no response.
 		{Refused: true, Status: 0},
-		// Answered 404 at smallwebwaf's own endpoints: neither forwarded
-		// nor refused.
+		// Answered 404 for a path under /_smallwebwaf/: neither forwarded nor
+		// refused.
 		{Status: 404},
 	} {
 		limiter.AddToHistory(client, start.Add(time.Duration(i)*time.Minute), r)

internal/ratelimit/ratelimit.go

@@ -92,10 +92,9 @@ type History struct {
 	ASName   string    `json:"as_name,omitempty"`
 	Country  string    `json:"country,omitempty"`
 	LookedUp time.Time `json:"looked_up,omitzero"`
-	// Requests are all the client's requests: Forwarded those passed to
-	// the app, Refused those refused before anything reached it, a 401 at
-	// smallwebwaf's own endpoints included, and neither the others
-	// smallwebwaf answered there.
+	// Requests are all the client's requests: Forwarded those servewaf allowed,
+	// Refused those it refused, and neither those for a path under
+	// /_smallwebwaf/.
 	Requests  int64 `json:"requests"`
 	Forwarded int64 `json:"forwarded"`
 	Refused   int64 `json:"refused"`
@@ -124,21 +123,20 @@ type Offences struct {
 	// Limit is its requests that broke a rate limit, a byte limit or the
 	// error burst, Attack those that were a clear sign of attack, a match
 	// of a ban rule or a request for a trap path, RuleBlocked those a block
-	// rule refused, WAFBlocked those the Core Rule Set refused, and
-	// TokenRefused those refused for a missing or wrong token.
-	Limit        int64 `json:"limit"`
-	Attack       int64 `json:"attack"`
-	RuleBlocked  int64 `json:"rule_blocked"`
-	WAFBlocked   int64 `json:"waf_blocked"`
-	TokenRefused int64 `json:"token_refused"`
+	// rule refused, and WAFBlocked those the Core Rule Set refused.
+	Limit       int64 `json:"limit"`
+	Attack      int64 `json:"attack"`
+	RuleBlocked int64 `json:"rule_blocked"`
+	WAFBlocked  int64 `json:"waf_blocked"`
+	// TokenRefused is what a clients.json written by an earlier version gives,
+	// which must still load. Nothing adds to it.
+	TokenRefused int64 `json:"token_refused,omitempty"`
 }
 
 // Request is what a client's history keeps of one of its requests.
 type Request struct {
-	// Forwarded is true for a request passed to the app, Refused for one
-	// refused before anything reached it, a 401 at smallwebwaf's own
-	// endpoints included. Both are false for any other request smallwebwaf
-	// answered there.
+	// Forwarded is true for a request servewaf allowed, and Refused for one it
+	// refused. Both are false for a request for a path under /_smallwebwaf/.
 	Forwarded bool
 	Refused   bool
 	// Status is what the client was sent, 0 if nothing was.
@@ -149,14 +147,12 @@ type Request struct {
 	ResponseBytes int64
 	// BrokeLimit is true for a request that broke a rate limit, a byte
 	// limit or the error burst, Attack for one that matched a ban rule or
-	// asked for a trap path, RuleBlocked for one a block rule refused,
-	// WAFBlocked for one the Core Rule Set refused, and TokenRefused for
-	// one refused for a missing or wrong token.
-	BrokeLimit   bool
-	Attack       bool
-	RuleBlocked  bool
-	WAFBlocked   bool
-	TokenRefused bool
+	// asked for a trap path, RuleBlocked for one a block rule refused, and
+	// WAFBlocked for one the Core Rule Set refused.
+	BrokeLimit  bool
+	Attack      bool
+	RuleBlocked bool
+	WAFBlocked  bool
 }
 
 // New returns a Limiter for limits, with no client counted yet, whose
@@ -334,10 +330,6 @@ func (l *Limiter) AddToHistory(client netip.Prefix, now time.Time, r Request) {
 	if r.WAFBlocked {
 		h.Offences.WAFBlocked++
 	}
-
-	if r.TokenRefused {
-		h.Offences.TokenRefused++
-	}
 }
 
 // AddLookup gives client's history its AS number, AS name and country, as

internal/requestlog/requestlog.go

@@ -14,19 +14,13 @@ import (
 	"sneak.berlin/go/smallwebwaf/internal/ratelimit"
 )
 
-// The action a request line names: what smallwebwaf did with the
-// request.
+// The action a request line names: what servewaf did with the request.
 const (
-	// ActionForward is a request passed to the app.
+	// ActionForward is a request servewaf allowed, which rproxy passes to the
+	// app.
 	ActionForward = "forward"
-	// ActionTooLarge is a request or response over its size limit, or, in
-	// servewaf, a request over the header limits.
+	// ActionTooLarge is a request over the header limits.
 	ActionTooLarge = "too_large"
-	// ActionTimedOut is a request or response that ran out of time.
-	ActionTimedOut = "timed_out"
-	// ActionUpstreamError is a request the app could not be reached
-	// for, or whose answer could not be passed on.
-	ActionUpstreamError = "upstream_error"
 	// ActionRateLimited is a request refused because it took its client
 	// over a rate limit, which bans the client.
 	ActionRateLimited = "rate_limited"
@@ -48,8 +42,8 @@ const (
 	ActionDenied = "denied"
 	// ActionCountryDenied is a request refused for its client's country.
 	ActionCountryDenied = "country_denied"
-	// ActionAdmin is a request smallwebwaf answered at one of its own
-	// endpoints, under /_smallwebwaf/.
+	// ActionAdmin is a request servewaf answered at one of its own endpoints,
+	// or a question about a path under /_smallwebwaf/.
 	ActionAdmin = "admin"
 )
 
@@ -86,8 +80,8 @@ type Line struct {
 	// two lines about a question.
 	ServeWAFLine string `json:"servewaf_line,omitempty"`
 
-	// The standard web log fields. Scheme is how the client reached
-	// smallwebwaf, or the trusted proxy in front of it.
+	// The standard web log fields. Scheme is how the client reached rproxy, or
+	// the trusted proxy in front of it.
 	Time          string `json:"time"`
 	Instance      string `json:"instance"`
 	ClientIP      string `json:"client_ip"`
@@ -103,8 +97,8 @@ type Line struct {
 	Referer       string `json:"referer"`
 	UserAgent     string `json:"user_agent"`
 
-	// Request detail. RequestID is the X-Request-ID a trusted proxy sent,
-	// or a new one, and is sent on to the app. ForwardedFor is the
+	// Request detail. RequestID is the id rproxy made for the request, or for a
+	// request to servewaf's own endpoints a new one. ForwardedFor is the
 	// X-Forwarded-For header as received. ClientGroup is the netblock the
 	// client is counted as. ASN, ASName and Country are the client's AS
 	// number, AS name and country, as looked up.
@@ -123,17 +117,10 @@ type Line struct {
 	RequestHeaders   map[string]string `json:"request_headers,omitempty"`
 	HasAuthorization bool              `json:"has_authorization,omitempty"`
 	HasCookie        bool              `json:"has_cookie,omitempty"`
-	// Websocket is true when the connection was upgraded, as for a
-	// WebSocket.
-	Websocket bool `json:"websocket,omitempty"`
 
-	// Response detail, from the headers of the answer: the app's, as
-	// passed on, or those of smallwebwaf's own. Aborted is true when the
-	// client went away early.
+	// Response detail, of servewaf's own answer. Aborted is true when rproxy, or
+	// the admin's tool, went away before the answer.
 	ResponseContentType string `json:"response_content_type,omitempty"`
-	UpstreamStatus      int    `json:"upstream_status,omitempty"`
-	CacheControl        string `json:"cache_control,omitempty"`
-	Location            string `json:"location,omitempty"`
 	Aborted             bool   `json:"aborted,omitempty"`
 
 	// The decision.
@@ -144,6 +131,16 @@ type Line struct {
 	// ActionRuleBlocked, ActionWAFBlocked, or, in servewaf, ActionTooLarge
 	// for the header limits.
 	WouldAction string `json:"would_action,omitempty"`
+	// Heuristic is the name of the heuristic that refused the request, in
+	// observe mode too, and HeuristicFigures are the figures it acted on, by
+	// name.
+	Heuristic        string         `json:"heuristic,omitempty"`
+	HeuristicFigures map[string]any `json:"heuristic_figures,omitempty"`
+	// AfterAnswerHeuristic and AfterAnswerHeuristicFigures are the same for
+	// the heuristic that banned the client after servewaf answered the
+	// request.
+	AfterAnswerHeuristic        string         `json:"after_answer_heuristic,omitempty"`
+	AfterAnswerHeuristicFigures map[string]any `json:"after_answer_heuristic_figures,omitempty"` //nolint:lll // a struct tag cannot be split
 	// LimitPercent and LimitPercentSetting are, for a request the rate
 	// limits counted whose client a biased threshold gives a percentage of
 	// the rate limits below 100, that percentage and the setting that gave
@@ -183,17 +180,13 @@ type Line struct {
 
 	// The timings, in milliseconds. DurationChecks is the time until the
 	// checks were done, and DurationWAF the part of it the Core Rule Set
-	// took. DurationUpstreamConnect, DurationUpstreamFirstByte and
-	// DurationUpstreamTotal run from when the request was handed to the
-	// app: until there was a connection to it, until the first byte of its
-	// answer arrived, and until the end. Each but DurationTotal is nil for
-	// a request that did not get that far.
-	DurationTotal             float64  `json:"duration_total"`
-	DurationChecks            *float64 `json:"duration_checks,omitempty"`
-	DurationWAF               *float64 `json:"duration_waf,omitempty"`
-	DurationUpstreamConnect   *float64 `json:"duration_upstream_connect,omitempty"`
-	DurationUpstreamFirstByte *float64 `json:"duration_upstream_first_byte,omitempty"`
-	DurationUpstreamTotal     *float64 `json:"duration_upstream_total,omitempty"`
+	// took. DurationUpstreamTotal is what the report of an allowed request gives,
+	// from the hand-over to the app until the end of its answer. Each but
+	// DurationTotal is nil for a request that did not get that far.
+	DurationTotal         float64  `json:"duration_total"`
+	DurationChecks        *float64 `json:"duration_checks,omitempty"`
+	DurationWAF           *float64 `json:"duration_waf,omitempty"`
+	DurationUpstreamTotal *float64 `json:"duration_upstream_total,omitempty"`
 }
 
 // RProxyLine is rproxy's short line in the request log about one request. The

internal/rproxy/limits_test.go

@@ -1,7 +1,9 @@
 package rproxy_test
 
 import (
+	"bufio"
 	"bytes"
+	"errors"
 	"io"
 	"log/slog"
 	"net"
@@ -14,9 +16,9 @@ import (
 	"time"
 
 	"sneak.berlin/go/smallwebwaf/internal/config"
-	"sneak.berlin/go/smallwebwaf/internal/proxy"
 	"sneak.berlin/go/smallwebwaf/internal/requestlog"
 	"sneak.berlin/go/smallwebwaf/internal/rproxy"
+	"sneak.berlin/go/smallwebwaf/internal/servewaf"
 )
 
 // post is the start of a POST whose headers end with what follows it.
@@ -69,11 +71,11 @@ func TestABodyAnnouncedOverItsLimitIsRefusedOnceServeWAFAllowsIt(t *testing.T) {
 		t.Run(tc.name, func(t *testing.T) {
 			t.Parallel()
 
-			servewaf := startServeWAF(t, allow)
+			standIn := startServeWAF(t, allow)
 			app := startApp(t, func(http.ResponseWriter, *http.Request) {
 				t.Error("the app was asked")
 			})
-			addr, _ := startRProxy(t, servewaf.URL, app.URL, map[string]string{
+			addr, _ := startRProxy(t, standIn.URL, app.URL, map[string]string{
 				maxRequestSize: tc.limit,
 			})
 
@@ -83,11 +85,11 @@ func TestABodyAnnouncedOverItsLimitIsRefusedOnceServeWAFAllowsIt(t *testing.T) {
 				t.Errorf("answered %+v, want 413", got)
 			}
 
-			if asked := servewaf.question(t); len(asked.body) != tc.asked {
+			if asked := standIn.question(t); len(asked.body) != tc.asked {
 				t.Errorf("the question carries %d bytes, want %d", len(asked.body), tc.asked)
 			}
 
-			report := servewaf.report(t)
+			report := standIn.report(t)
 			if report.Status != http.StatusRequestEntityTooLarge {
 				t.Errorf("report %+v, want status 413", report)
 			}
@@ -98,9 +100,9 @@ func TestABodyAnnouncedOverItsLimitIsRefusedOnceServeWAFAllowsIt(t *testing.T) {
 func TestADenyOutranksTheBodySizeLimit(t *testing.T) {
 	t.Parallel()
 
-	servewaf := startServeWAF(t, deny)
+	standIn := startServeWAF(t, deny)
 	app := startApp(t, greet)
-	addr, _ := startRProxy(t, servewaf.URL, app.URL, map[string]string{
+	addr, _ := startRProxy(t, standIn.URL, app.URL, map[string]string{
 		maxRequestSize: "1K",
 	})
 
@@ -130,12 +132,12 @@ func TestABodyNotAnnouncedOverItsLimitIsRefused(t *testing.T) {
 
 			var asked atomic.Bool
 
-			servewaf := startServeWAF(t, allow)
+			standIn := startServeWAF(t, allow)
 			app := startApp(t, func(w http.ResponseWriter, r *http.Request) {
 				asked.Store(true)
 				greet(w, r)
 			})
-			addr, _ := startRProxy(t, servewaf.URL, app.URL, map[string]string{
+			addr, _ := startRProxy(t, standIn.URL, app.URL, map[string]string{
 				maxRequestSize: tc.limit,
 			})
 
@@ -163,12 +165,12 @@ func TestAResponseOverItsLimit(t *testing.T) {
 	t.Run("announced, is refused", func(t *testing.T) {
 		t.Parallel()
 
-		servewaf := startServeWAF(t, allow)
+		standIn := startServeWAF(t, allow)
 		app := startApp(t, func(w http.ResponseWriter, _ *http.Request) {
 			w.Header().Set(contentLengthHeader, strconv.Itoa(len(large)))
 			_, _ = io.WriteString(w, large)
 		})
-		addr, _ := startRProxy(t, servewaf.URL, app.URL, map[string]string{
+		addr, _ := startRProxy(t, standIn.URL, app.URL, map[string]string{
 			maxResponseSize: "1K",
 		})
 
@@ -177,7 +179,7 @@ func TestAResponseOverItsLimit(t *testing.T) {
 			t.Errorf("answered %d, want 502", got.status)
 		}
 
-		if report := servewaf.report(t); report.Status != http.StatusBadGateway {
+		if report := standIn.report(t); report.Status != http.StatusBadGateway {
 			t.Errorf("report %+v, want status 502", report)
 		}
 	})
@@ -185,13 +187,13 @@ func TestAResponseOverItsLimit(t *testing.T) {
 	t.Run("not announced, is cut off", func(t *testing.T) {
 		t.Parallel()
 
-		servewaf := startServeWAF(t, allow)
+		standIn := startServeWAF(t, allow)
 		app := startApp(t, func(w http.ResponseWriter, _ *http.Request) {
 			_, _ = io.WriteString(w, large[:1])
 			_ = http.NewResponseController(w).Flush()
 			_, _ = io.WriteString(w, large[1:])
 		})
-		addr, _ := startRProxy(t, servewaf.URL, app.URL, map[string]string{
+		addr, _ := startRProxy(t, standIn.URL, app.URL, map[string]string{
 			maxResponseSize: "1K",
 		})
 
@@ -203,7 +205,7 @@ func TestAResponseOverItsLimit(t *testing.T) {
 			t.Errorf("read %d bytes (%v), want the answer cut off", len(text), err)
 		}
 
-		report := servewaf.report(t)
+		report := standIn.report(t)
 		if report.Status != http.StatusOK || report.ResponseBytes > 1<<10 {
 			t.Errorf("report %+v, want status 200 and at most 1K of the answer", report)
 		}
@@ -215,11 +217,11 @@ func TestAHeadWhoseAnswerAnnouncesMoreThanTheResponseLimitIsPassedOn(t *testing.
 
 	const announced = "2048"
 
-	servewaf := startServeWAF(t, allow)
+	standIn := startServeWAF(t, allow)
 	app := startApp(t, func(w http.ResponseWriter, _ *http.Request) {
 		w.Header().Set(contentLengthHeader, announced)
 	})
-	addr, _ := startRProxy(t, servewaf.URL, app.URL, map[string]string{
+	addr, _ := startRProxy(t, standIn.URL, app.URL, map[string]string{
 		maxResponseSize: "1K",
 	})
 
@@ -238,9 +240,9 @@ func TestASettingOfOffSetsNoLimit(t *testing.T) {
 		t.Run(setting, func(t *testing.T) {
 			t.Parallel()
 
-			servewaf := startServeWAF(t, allow)
+			standIn := startServeWAF(t, allow)
 			app := startApp(t, greet)
-			addr, _ := startRProxy(t, servewaf.URL, app.URL, map[string]string{
+			addr, _ := startRProxy(t, standIn.URL, app.URL, map[string]string{
 				setting: "off",
 			})
 
@@ -249,7 +251,7 @@ func TestASettingOfOffSetsNoLimit(t *testing.T) {
 			wantGreeting(t, visit(t, newRequest(t, http.MethodPost, addr, "/",
 				strings.NewReader("a body"))))
 
-			if got := get(t, addr, proxy.HealthPath); got.status != http.StatusOK {
+			if got := get(t, addr, servewaf.HealthPath); got.status != http.StatusOK {
 				t.Errorf("answered %+v, want rproxy's own 200", got)
 			}
 		})
@@ -268,9 +270,9 @@ func TestAVisitorTooSlowToSendTheFirstPartIsAnswered408(t *testing.T) {
 		t.Run(tc.name, func(t *testing.T) {
 			t.Parallel()
 
-			servewaf := startServeWAF(t, allow)
+			standIn := startServeWAF(t, allow)
 			app := startApp(t, greet)
-			addr, out := startRProxy(t, servewaf.URL, app.URL, map[string]string{
+			addr, out := startRProxy(t, standIn.URL, app.URL, map[string]string{
 				maxRequestTime: "500",
 			})
 
@@ -286,11 +288,11 @@ func TestAVisitorTooSlowToSendTheFirstPartIsAnswered408(t *testing.T) {
 				t.Errorf("line %v, want no disposition and 10 bytes", line)
 			}
 
-			if len(servewaf.questions) != 0 {
+			if len(standIn.questions) != 0 {
 				t.Error("servewaf was asked")
 			}
 
-			servewaf.wantNoReport(t)
+			standIn.wantNoReport(t)
 		})
 	}
 }
@@ -298,9 +300,9 @@ func TestAVisitorTooSlowToSendTheFirstPartIsAnswered408(t *testing.T) {
 func TestAVisitorThatGoesAwayBeforeTheFirstPartIsNotAsked(t *testing.T) {
 	t.Parallel()
 
-	servewaf := startServeWAF(t, allow)
+	standIn := startServeWAF(t, allow)
 	app := startApp(t, greet)
-	addr, out := startRProxy(t, servewaf.URL, app.URL, nil)
+	addr, out := startRProxy(t, standIn.URL, app.URL, nil)
 
 	conn := dial(t, addr)
 	send(t, conn, post+announcedLength(100)+"some of it")
@@ -311,7 +313,7 @@ func TestAVisitorThatGoesAwayBeforeTheFirstPartIsNotAsked(t *testing.T) {
 		t.Errorf("line %v, want no answer and no disposition", line)
 	}
 
-	if len(servewaf.questions) != 0 {
+	if len(standIn.questions) != 0 {
 		t.Error("servewaf was asked")
 	}
 }
@@ -332,9 +334,9 @@ func TestABodyThatCannotBeReadClosesTheConnectionWithoutAnAnswer(t *testing.T) {
 		t.Run(tc.name, func(t *testing.T) {
 			t.Parallel()
 
-			servewaf := startServeWAF(t, allow)
+			standIn := startServeWAF(t, allow)
 			app := startApp(t, greet)
-			addr, out := startRProxy(t, servewaf.URL, app.URL, nil)
+			addr, out := startRProxy(t, standIn.URL, app.URL, nil)
 
 			conn := dial(t, addr)
 			send(t, conn, tc.request)
@@ -362,7 +364,7 @@ func TestABodyThatCannotBeReadClosesTheConnectionWithoutAnAnswer(t *testing.T) {
 				t.Errorf("line %v, want no answer and no disposition", line)
 			}
 
-			if len(servewaf.questions) != 0 {
+			if len(standIn.questions) != 0 {
 				t.Error("servewaf was asked")
 			}
 		})
@@ -402,11 +404,11 @@ func TestABodyLeftUnreadIsReadOnlyUntilTheRequestTimeLimit(t *testing.T) {
 		announced = 100 * questionBodyMaxBytes
 	)
 
-	servewaf := startServeWAF(t, allow)
+	standIn := startServeWAF(t, allow)
 	app := startApp(t, func(w http.ResponseWriter, _ *http.Request) {
 		w.WriteHeader(http.StatusNoContent)
 	})
-	_, _, server := startServer(t, servewaf.URL, app.URL, map[string]string{
+	_, _, server := startServer(t, standIn.URL, app.URL, map[string]string{
 		maxRequestTime: strconv.FormatInt(limit.Milliseconds(), 10),
 	})
 
@@ -452,9 +454,9 @@ func TestAnAnswerRProxyGivesItselfHasTheResponseTimeToBeSent(t *testing.T) {
 		t.Run(tc.name, func(t *testing.T) {
 			t.Parallel()
 
-			servewaf := startServeWAF(t, deny)
+			standIn := startServeWAF(t, deny)
 			app := startApp(t, greet)
-			_, _, server := startServer(t, servewaf.URL, app.URL, map[string]string{
+			_, _, server := startServer(t, standIn.URL, app.URL, map[string]string{
 				maxResponseTime: strconv.FormatInt(limit.Milliseconds(), 10),
 			})
 
@@ -482,9 +484,9 @@ func TestAnAnswerRProxyGivesItselfHasTheResponseTimeToBeSent(t *testing.T) {
 func TestAVisitorTooSlowToSendTheRestIsAnswered408(t *testing.T) {
 	t.Parallel()
 
-	servewaf := startServeWAF(t, allow)
+	standIn := startServeWAF(t, allow)
 	app := startApp(t, greet)
-	addr, _ := startRProxy(t, servewaf.URL, app.URL, map[string]string{
+	addr, _ := startRProxy(t, standIn.URL, app.URL, map[string]string{
 		maxRequestTime: "3000",
 	})
 
@@ -496,11 +498,11 @@ func TestAVisitorTooSlowToSendTheRestIsAnswered408(t *testing.T) {
 		t.Errorf("status %d, want 408", status)
 	}
 
-	if asked := servewaf.question(t); len(asked.body) != questionBodyMaxBytes {
+	if asked := standIn.question(t); len(asked.body) != questionBodyMaxBytes {
 		t.Errorf("the question carries %d bytes", len(asked.body))
 	}
 
-	if report := servewaf.report(t); report.Status != http.StatusRequestTimeout {
+	if report := standIn.report(t); report.Status != http.StatusRequestTimeout {
 		t.Errorf("report %+v, want status 408", report)
 	}
 }
@@ -551,8 +553,8 @@ func TestAnAppTooSlowToTakeTheRequestIsAnswered504(t *testing.T) {
 		writeSize = 32 << 10
 	)
 
-	servewaf := startServeWAF(t, allow)
-	addr, _ := startRProxy(t, servewaf.URL, startAppThatTakesNothing(t),
+	standIn := startServeWAF(t, allow)
+	addr, _ := startRProxy(t, standIn.URL, startAppThatTakesNothing(t),
 		map[string]string{maxRequestTime: "3000"})
 
 	conn := dial(t, addr)
@@ -578,14 +580,14 @@ func TestAnAppTooSlowToAnswerIsAnswered504(t *testing.T) {
 	t.Parallel()
 
 	release := make(chan struct{})
-	servewaf := startServeWAF(t, allow)
+	standIn := startServeWAF(t, allow)
 	app := startApp(t, func(http.ResponseWriter, *http.Request) {
 		<-release
 	})
 
 	t.Cleanup(func() { close(release) })
 
-	addr, _ := startRProxy(t, servewaf.URL, app.URL, map[string]string{
+	addr, _ := startRProxy(t, standIn.URL, app.URL, map[string]string{
 		maxResponseTime: "300",
 	})
 
@@ -594,7 +596,7 @@ func TestAnAppTooSlowToAnswerIsAnswered504(t *testing.T) {
 		t.Errorf("answered %d, want 504", got.status)
 	}
 
-	if report := servewaf.report(t); report.Status != http.StatusGatewayTimeout {
+	if report := standIn.report(t); report.Status != http.StatusGatewayTimeout {
 		t.Errorf("report %+v, want status 504", report)
 	}
 }
@@ -602,10 +604,12 @@ func TestAnAppTooSlowToAnswerIsAnswered504(t *testing.T) {
 func TestAnAppTooSlowToFinishItsAnswerIsCutOff(t *testing.T) {
 	t.Parallel()
 
+	const start = "the start"
+
 	release := make(chan struct{})
-	servewaf := startServeWAF(t, allow)
+	standIn := startServeWAF(t, allow)
 	app := startApp(t, func(w http.ResponseWriter, _ *http.Request) {
-		_, _ = io.WriteString(w, "the start")
+		_, _ = io.WriteString(w, start)
 		_ = http.NewResponseController(w).Flush()
 
 		<-release
@@ -613,20 +617,32 @@ func TestAnAppTooSlowToFinishItsAnswerIsCutOff(t *testing.T) {
 
 	t.Cleanup(func() { close(release) })
 
-	addr, _ := startRProxy(t, servewaf.URL, app.URL, map[string]string{
-		maxResponseTime: "300",
+	// The time limit is long enough for a loaded host to pass on the start of the
+	// answer before it runs out.
+	addr, _ := startRProxy(t, standIn.URL, app.URL, map[string]string{
+		maxResponseTime: "3000",
 	})
 
 	conn := dial(t, addr)
 	send(t, conn, "GET / HTTP/1.1\r\nHost: site.example\r\n\r\n")
 
-	// dial's deadline ends this read with an error if the connection stays open.
-	_, err := io.ReadAll(conn)
+	res, err := http.ReadResponse(bufio.NewReader(conn), nil)
 	if err != nil {
-		t.Errorf("read: %v, want the connection closed", err)
+		t.Fatalf("read the answer: %v", err)
 	}
 
-	if report := servewaf.report(t); report.Status != http.StatusOK {
+	// The body breaks off when rproxy closes the connection. If the connection
+	// stays open, dial's deadline ends this read with a timeout instead.
+	body, err := io.ReadAll(res.Body)
+	_ = res.Body.Close()
+
+	if res.StatusCode != http.StatusOK || string(body) != start ||
+		!errors.Is(err, io.ErrUnexpectedEOF) {
+		t.Errorf("answered %d %q (%v), want the app's 200 %q, then the connection closed",
+			res.StatusCode, body, err, start)
+	}
+
+	if report := standIn.report(t); report.Status != http.StatusOK {
 		t.Errorf("report %+v, want the status the visitor got", report)
 	}
 }
@@ -640,7 +656,7 @@ func TestAVisitorTooSlowToTakeTheAnswerIsCutOff(t *testing.T) {
 		writeSize = 32 << 10
 	)
 
-	servewaf := startServeWAF(t, allow)
+	standIn := startServeWAF(t, allow)
 	app := startApp(t, func(w http.ResponseWriter, _ *http.Request) {
 		part := make([]byte, writeSize)
 
@@ -651,8 +667,10 @@ func TestAVisitorTooSlowToTakeTheAnswerIsCutOff(t *testing.T) {
 			}
 		}
 	})
-	addr, out := startRProxy(t, servewaf.URL, app.URL, map[string]string{
-		maxResponseTime: "500",
+	// The time limit is long enough for a loaded host to start passing on the
+	// answer before it runs out.
+	addr, out := startRProxy(t, standIn.URL, app.URL, map[string]string{
+		maxResponseTime: "3000",
 	})
 
 	// The visitor asks, and never reads the answer.
@@ -666,7 +684,7 @@ func TestAVisitorTooSlowToTakeTheAnswerIsCutOff(t *testing.T) {
 		t.Errorf("line %v, want status 200 and the answer cut off", line)
 	}
 
-	report := servewaf.report(t)
+	report := standIn.report(t)
 	if report.Status != http.StatusOK || report.ResponseBytes >= bodySize {
 		t.Errorf("report %+v, want status 200 and the answer cut off", report)
 	}
@@ -675,15 +693,15 @@ func TestAVisitorTooSlowToTakeTheAnswerIsCutOff(t *testing.T) {
 func TestAnAppThatCannotBeReachedIsAnswered502WithAReport(t *testing.T) {
 	t.Parallel()
 
-	servewaf := startServeWAF(t, allow)
-	addr, _ := startRProxy(t, servewaf.URL, nowhere, nil)
+	standIn := startServeWAF(t, allow)
+	addr, _ := startRProxy(t, standIn.URL, nowhere, nil)
 
 	got := get(t, addr, "/")
 	if got.status != http.StatusBadGateway {
 		t.Errorf("answered %d, want 502", got.status)
 	}
 
-	if report := servewaf.report(t); report.Status != http.StatusBadGateway {
+	if report := standIn.report(t); report.Status != http.StatusBadGateway {
 		t.Errorf("report %+v, want status 502", report)
 	}
 }
@@ -691,11 +709,11 @@ func TestAnAppThatCannotBeReachedIsAnswered502WithAReport(t *testing.T) {
 func TestAVisitorThatStopsSendingAfterTheAppHasAnsweredGetsTheAnswer(t *testing.T) {
 	t.Parallel()
 
-	servewaf := startServeWAF(t, allow)
+	standIn := startServeWAF(t, allow)
 	app := startApp(t, func(w http.ResponseWriter, _ *http.Request) {
 		_, _ = io.WriteString(w, greeting)
 	})
-	addr, _ := startRProxy(t, servewaf.URL, app.URL, map[string]string{
+	addr, _ := startRProxy(t, standIn.URL, app.URL, map[string]string{
 		maxRequestTime: "3000",
 	})
 
@@ -714,12 +732,12 @@ func TestAVisitorThatStopsSendingWhileTheAppWorksGetsNoAnswer(t *testing.T) {
 	t.Parallel()
 
 	working := make(chan struct{})
-	servewaf := startServeWAF(t, allow)
+	standIn := startServeWAF(t, allow)
 	app := startApp(t, func(_ http.ResponseWriter, r *http.Request) {
 		close(working)
 		<-r.Context().Done()
 	})
-	addr, out := startRProxy(t, servewaf.URL, app.URL, nil)
+	addr, out := startRProxy(t, standIn.URL, app.URL, nil)
 
 	conn := dial(t, addr)
 	send(t, conn, "GET / HTTP/1.1\r\nHost: site.example\r\n\r\n")
@@ -755,7 +773,7 @@ func TestTheRequestTimeLimitDoesNotCutAnAnswerOnceTheAppHasTheRequest(t *testing
 
 	const answer = "the end of a long answer"
 
-	servewaf := startServeWAF(t, allow)
+	standIn := startServeWAF(t, allow)
 	app := startApp(t, func(w http.ResponseWriter, r *http.Request) {
 		_, _ = io.Copy(io.Discard, r.Body)
 		_ = http.NewResponseController(w).Flush()
@@ -764,7 +782,7 @@ func TestTheRequestTimeLimitDoesNotCutAnAnswerOnceTheAppHasTheRequest(t *testing
 
 		_, _ = io.WriteString(w, answer)
 	})
-	addr, _ := startRProxy(t, servewaf.URL, app.URL, map[string]string{
+	addr, _ := startRProxy(t, standIn.URL, app.URL, map[string]string{
 		maxRequestTime: "2000",
 	})
 
@@ -784,17 +802,19 @@ func TestAVisitorThatStopsSendingGetsAnAnswerRProxyGivesByTheDeadline(t *testing
 		{"a deny", post, http.StatusForbidden},
 		{
 			"the health check",
-			"GET " + proxy.HealthPath + " HTTP/1.1\r\nHost: site.example\r\n",
+			"GET " + servewaf.HealthPath + " HTTP/1.1\r\nHost: site.example\r\n",
 			http.StatusOK,
 		},
 	} {
 		t.Run(tc.name, func(t *testing.T) {
 			t.Parallel()
 
-			servewaf := startServeWAF(t, deny)
+			standIn := startServeWAF(t, deny)
 			app := startApp(t, greet)
-			addr, _ := startRProxy(t, servewaf.URL, app.URL, map[string]string{
-				maxRequestTime: "500",
+			// The time limit is long enough for a loaded host to read the first part of
+			// the body before it runs out.
+			addr, _ := startRProxy(t, standIn.URL, app.URL, map[string]string{
+				maxRequestTime: "3000",
 			})
 
 			// Go's server waits for a little of the body left before it sends an answer,

internal/rproxy/question_test.go

@@ -12,11 +12,11 @@ import (
 	"strings"
 	"testing"
 
-	"sneak.berlin/go/smallwebwaf/internal/proxy"
+	"sneak.berlin/go/smallwebwaf/internal/servewaf"
 )
 
 // questionBodyMaxBytes is the most of a body a question carries.
-const questionBodyMaxBytes = proxy.QuestionBodyMaxBytes
+const questionBodyMaxBytes = servewaf.QuestionBodyMaxBytes
 
 // chunked is the encoding of a body whose length the visitor did not announce.
 const chunked = "chunked"
@@ -29,9 +29,9 @@ const pathGoReencodes = "/some%2Fpath/with%20space|pipe"
 func TestQuestionIsTheVisitorsRequestWithRProxysHeaders(t *testing.T) {
 	t.Parallel()
 
-	servewaf := startServeWAF(t, allow)
+	standIn := startServeWAF(t, allow)
 	app := startApp(t, greet)
-	addr, _ := startRProxy(t, servewaf.URL, app.URL, nil)
+	addr, _ := startRProxy(t, standIn.URL, app.URL, nil)
 
 	const target = pathGoReencodes + "?b=2&a=1&bad=%zz;x"
 
@@ -42,16 +42,16 @@ func TestQuestionIsTheVisitorsRequestWithRProxysHeaders(t *testing.T) {
 	req.Header.Set(forwardedForHeader, "198.51.100.1")
 	req.Header.Set(forwardedProtoHeader, "gopher")
 	req.Header.Set(requestIDHeader, "the-visitor's")
-	req.Header.Set(proxy.ClientHeader, "198.51.100.2")
-	req.Header.Set(proxy.PeerHeader, "198.51.100.3")
-	req.Header.Set(proxy.ContentLengthHeader, "12345")
+	req.Header.Set(servewaf.ClientHeader, "198.51.100.2")
+	req.Header.Set(servewaf.PeerHeader, "198.51.100.3")
+	req.Header.Set(servewaf.ContentLengthHeader, "12345")
 	// Go's client then sends no User-Agent, so that one in the question would be
 	// Go's own.
 	req.Header["User-Agent"] = nil
 
 	wantGreeting(t, visit(t, req))
 
-	asked := servewaf.question(t)
+	asked := standIn.question(t)
 	if asked.method != http.MethodDelete || asked.target != target ||
 		asked.host != site {
 		t.Errorf("asked about %s %s at %s", asked.method, asked.target, asked.host)
@@ -68,8 +68,8 @@ func TestQuestionIsTheVisitorsRequestWithRProxysHeaders(t *testing.T) {
 	want.Set(forwardedForHeader, "198.51.100.1")
 	want.Set(forwardedProtoHeader, "http")
 	want.Set(requestIDHeader, asked.header.Get(requestIDHeader))
-	want.Set(proxy.ClientHeader, localhost)
-	want.Set(proxy.PeerHeader, localhost)
+	want.Set(servewaf.ClientHeader, localhost)
+	want.Set(servewaf.PeerHeader, localhost)
 
 	if !maps.EqualFunc(asked.header, want, slices.Equal) {
 		t.Errorf("the question's headers are %v, want %v", asked.header, want)
@@ -93,14 +93,14 @@ func TestQuestionNamesTheVisitorATrustedProxySpeaksFor(t *testing.T) {
 		t.Run(tc.name, func(t *testing.T) {
 			t.Parallel()
 
-			servewaf := startServeWAF(t, allow)
+			standIn := startServeWAF(t, allow)
 			forwarded := make(chan http.Header, 1)
 			app := startApp(t, func(w http.ResponseWriter, r *http.Request) {
 				forwarded <- r.Header.Clone()
 
 				greet(w, r)
 			})
-			addr, out := startRProxy(t, servewaf.URL, app.URL, map[string]string{
+			addr, out := startRProxy(t, standIn.URL, app.URL, map[string]string{
 				trustedProxies: tc.trusted,
 			})
 
@@ -109,9 +109,9 @@ func TestQuestionNamesTheVisitorATrustedProxySpeaksFor(t *testing.T) {
 			req.Header.Set(forwardedProtoHeader, "https")
 			wantGreeting(t, visit(t, req))
 
-			asked := servewaf.question(t)
-			if asked.header.Get(proxy.ClientHeader) != tc.client ||
-				asked.header.Get(proxy.PeerHeader) != localhost ||
+			asked := standIn.question(t)
+			if asked.header.Get(servewaf.ClientHeader) != tc.client ||
+				asked.header.Get(servewaf.PeerHeader) != localhost ||
 				asked.header.Get(forwardedForHeader) != visitor ||
 				asked.header.Get(forwardedProtoHeader) != tc.proto {
 				t.Errorf("the question's headers are %v", asked.header)
@@ -128,6 +128,52 @@ func TestQuestionNamesTheVisitorATrustedProxySpeaksFor(t *testing.T) {
 	}
 }
 
+func TestQuestionNamesTheClientAsTheForwardedAddressesSay(t *testing.T) {
+	t.Parallel()
+
+	for _, tc := range []struct {
+		name   string
+		header []string
+		client string
+	}{
+		{
+			"the first address outside the trusted proxies, from the right",
+			[]string{"198.51.100.7, 203.0.113.9, 10.0.0.2"}, "203.0.113.9",
+		},
+		{
+			"the leftmost, when every address is a trusted proxy",
+			[]string{"10.0.0.5, 10.0.0.2"}, "10.0.0.5",
+		},
+		{"the peer, with no header", nil, localhost},
+		{
+			"the last address read, before an entry that is not an address",
+			[]string{"203.0.113.9, unknown, 10.0.0.2"}, "10.0.0.2",
+		},
+		{
+			"read as one list, with several header lines",
+			[]string{"2001:db8::7", "10.0.0.2"}, "2001:db8::7",
+		},
+	} {
+		t.Run(tc.name, func(t *testing.T) {
+			t.Parallel()
+
+			standIn := startServeWAF(t, allow)
+			app := startApp(t, greet)
+			addr, _ := startRProxy(t, standIn.URL, app.URL, map[string]string{
+				trustedProxies: localhost + "/32,10.0.0.0/8",
+			})
+
+			req := newRequest(t, http.MethodGet, addr, "/", http.NoBody)
+			req.Header[forwardedForHeader] = tc.header
+			wantGreeting(t, visit(t, req))
+
+			if got := standIn.question(t).header.Get(servewaf.ClientHeader); got != tc.client {
+				t.Errorf("the question names %s, want %s", got, tc.client)
+			}
+		})
+	}
+}
+
 // randomBytes returns n random bytes.
 func randomBytes(n int) []byte {
 	body := make([]byte, n)
@@ -151,7 +197,7 @@ func TestFirst64KiBReachServeWAFAndTheWholeBodyTheApp(t *testing.T) {
 				t.Parallel()
 
 				body := randomBytes(size)
-				servewaf := startServeWAF(t, allow)
+				standIn := startServeWAF(t, allow)
 				received := make(chan []byte, 1)
 				app := startApp(t, func(w http.ResponseWriter, r *http.Request) {
 					whole, _ := io.ReadAll(r.Body)
@@ -159,7 +205,7 @@ func TestFirst64KiBReachServeWAFAndTheWholeBodyTheApp(t *testing.T) {
 
 					greet(w, r)
 				})
-				addr, _ := startRProxy(t, servewaf.URL, app.URL, nil)
+				addr, _ := startRProxy(t, standIn.URL, app.URL, nil)
 
 				req := newRequest(t, http.MethodPost, addr, "/", bytes.NewReader(body))
 				if !announced {
@@ -169,7 +215,7 @@ func TestFirst64KiBReachServeWAFAndTheWholeBodyTheApp(t *testing.T) {
 
 				wantGreeting(t, visit(t, req))
 
-				asked := servewaf.question(t)
+				asked := standIn.question(t)
 				want := body[:min(size, questionBodyMaxBytes)]
 				wantQuestionBody(t, asked, want, size, announced)
 
@@ -177,7 +223,7 @@ func TestFirst64KiBReachServeWAFAndTheWholeBodyTheApp(t *testing.T) {
 					t.Error("the app did not get the whole body")
 				}
 
-				if report := servewaf.report(t); report.RequestBytes != int64(size) {
+				if report := standIn.report(t); report.RequestBytes != int64(size) {
 					t.Errorf("report %+v, of %d bytes", report, size)
 				}
 			})
@@ -197,7 +243,7 @@ func wantQuestionBody(
 			len(want))
 	}
 
-	values := asked.header.Values(proxy.ContentLengthHeader)
+	values := asked.header.Values(servewaf.ContentLengthHeader)
 
 	if announced {
 		if !slices.Equal(values, []string{strconv.Itoa(size)}) ||
@@ -218,9 +264,9 @@ func wantQuestionBody(
 func TestDenyNeedsOnlyTheFirstPartOfALargeBody(t *testing.T) {
 	t.Parallel()
 
-	servewaf := startServeWAF(t, deny)
+	standIn := startServeWAF(t, deny)
 	app := startApp(t, greet)
-	addr, _ := startRProxy(t, servewaf.URL, app.URL, nil)
+	addr, _ := startRProxy(t, standIn.URL, app.URL, nil)
 
 	// Far more announced than sent. Go's server does not wait for that much, so
 	// the answer comes at once.
@@ -232,7 +278,7 @@ func TestDenyNeedsOnlyTheFirstPartOfALargeBody(t *testing.T) {
 		t.Errorf("status %d, want servewaf's 403", status)
 	}
 
-	if report := servewaf.report(t); report.RequestBytes != questionBodyMaxBytes {
+	if report := standIn.report(t); report.RequestBytes != questionBodyMaxBytes {
 		t.Errorf("report %+v, want the first part's bytes", report)
 	}
 }
@@ -260,8 +306,8 @@ func TestAQuestionCarriesItsBodyWhateverTheMethod(t *testing.T) {
 			t.Run(method+" "+tc.name, func(t *testing.T) {
 				t.Parallel()
 
-				servewaf := startServeWAF(t, deny)
-				addr, _ := startRProxy(t, servewaf.URL, nowhere, nil)
+				standIn := startServeWAF(t, deny)
+				addr, _ := startRProxy(t, standIn.URL, nowhere, nil)
 
 				conn := dial(t, addr)
 				send(t, conn, method+" /x HTTP/1.1\r\nHost: site.example\r\n"+tc.framing)
@@ -270,7 +316,7 @@ func TestAQuestionCarriesItsBodyWhateverTheMethod(t *testing.T) {
 					t.Errorf("status %d, want servewaf's 403", status)
 				}
 
-				asked := servewaf.question(t)
+				asked := standIn.question(t)
 				if string(asked.body) != tc.body ||
 					!slices.Equal(asked.transferEncoding, tc.encoding) {
 					t.Errorf("the question carries %q, encoded %v, want %q, encoded %v",
@@ -288,11 +334,11 @@ func TestAMethodNotPassedOnIsAnswered405(t *testing.T) {
 		t.Run(method, func(t *testing.T) {
 			t.Parallel()
 
-			servewaf := startServeWAF(t, allow)
+			standIn := startServeWAF(t, allow)
 			app := startApp(t, func(http.ResponseWriter, *http.Request) {
 				t.Error("the app was asked")
 			})
-			addr, out := startRProxy(t, servewaf.URL, app.URL, nil)
+			addr, out := startRProxy(t, standIn.URL, app.URL, nil)
 
 			got := visit(t, newRequest(t, method, addr, "/", http.NoBody))
 			if got.status != http.StatusMethodNotAllowed ||
@@ -306,11 +352,11 @@ func TestAMethodNotPassedOnIsAnswered405(t *testing.T) {
 				t.Errorf("line %v, want status 405 and no disposition", line)
 			}
 
-			if len(servewaf.questions) != 0 {
+			if len(standIn.questions) != 0 {
 				t.Error("servewaf was asked")
 			}
 
-			servewaf.wantNoReport(t)
+			standIn.wantNoReport(t)
 		})
 	}
 }
@@ -326,18 +372,18 @@ func TestEachMethodPassedOnReachesServeWAFAndTheApp(t *testing.T) {
 			t.Parallel()
 
 			reached := make(chan string, 1)
-			servewaf := startServeWAF(t, allow)
+			standIn := startServeWAF(t, allow)
 			app := startApp(t, func(_ http.ResponseWriter, r *http.Request) {
 				reached <- r.Method
 			})
-			addr, _ := startRProxy(t, servewaf.URL, app.URL, nil)
+			addr, _ := startRProxy(t, standIn.URL, app.URL, nil)
 
 			got := visit(t, newRequest(t, method, addr, "/", http.NoBody))
 			if got.status != http.StatusOK {
 				t.Errorf("answered %+v, want the app's 200", got)
 			}
 
-			if asked := servewaf.question(t); asked.method != method {
+			if asked := standIn.question(t); asked.method != method {
 				t.Errorf("servewaf was asked about %s", asked.method)
 			}
 
@@ -370,9 +416,9 @@ func TestARequestThatCannotGoToServeWAFAsSentIsRefused(t *testing.T) {
 		t.Run(name, func(t *testing.T) {
 			t.Parallel()
 
-			servewaf := startServeWAF(t, allow)
+			standIn := startServeWAF(t, allow)
 			app := startApp(t, greet)
-			addr, out := startRProxy(t, servewaf.URL, app.URL, nil)
+			addr, out := startRProxy(t, standIn.URL, app.URL, nil)
 
 			conn := dial(t, addr)
 			send(t, conn, request)
@@ -387,11 +433,11 @@ func TestARequestThatCannotGoToServeWAFAsSentIsRefused(t *testing.T) {
 				t.Errorf("line %v, want status 400 and no disposition", line)
 			}
 
-			if len(servewaf.questions) != 0 {
+			if len(standIn.questions) != 0 {
 				t.Error("servewaf was asked")
 			}
 
-			servewaf.wantNoReport(t)
+			standIn.wantNoReport(t)
 		})
 	}
 }
@@ -401,9 +447,9 @@ func TestAHostWithAPercentSignButNoBracketGoesToServeWAF(t *testing.T) {
 
 	const host = "a%b"
 
-	servewaf := startServeWAF(t, allow)
+	standIn := startServeWAF(t, allow)
 	app := startApp(t, greet)
-	addr, _ := startRProxy(t, servewaf.URL, app.URL, nil)
+	addr, _ := startRProxy(t, standIn.URL, app.URL, nil)
 
 	conn := dial(t, addr)
 	send(t, conn, "GET / HTTP/1.1\r\nHost: "+host+"\r\n\r\n")
@@ -412,7 +458,7 @@ func TestAHostWithAPercentSignButNoBracketGoesToServeWAF(t *testing.T) {
 		t.Errorf("status %d, want the app's 200", status)
 	}
 
-	if asked := servewaf.question(t); asked.host != host {
+	if asked := standIn.question(t); asked.host != host {
 		t.Errorf("asked about the host %q, want %q", asked.host, host)
 	}
 }
@@ -422,15 +468,15 @@ func TestATrustedPeerWithNoForwardedProtoIsAskedAboutAsHTTP(t *testing.T) {
 
 	const want = "http"
 
-	servewaf := startServeWAF(t, allow)
+	standIn := startServeWAF(t, allow)
 	app := startApp(t, greet)
-	addr, _ := startRProxy(t, servewaf.URL, app.URL, map[string]string{
+	addr, _ := startRProxy(t, standIn.URL, app.URL, map[string]string{
 		trustedProxies: localhost + "/32",
 	})
 
 	wantGreeting(t, get(t, addr, "/"))
 
-	asked := servewaf.question(t)
+	asked := standIn.question(t)
 	if got := asked.header.Get(forwardedProtoHeader); got != want {
 		t.Errorf("the question's %s is %q, want %s", forwardedProtoHeader, got, want)
 	}
@@ -451,9 +497,9 @@ func TestAQuestionNamesNoZone(t *testing.T) {
 		t.Run(tc.name, func(t *testing.T) {
 			t.Parallel()
 
-			servewaf := startServeWAF(t, deny)
+			standIn := startServeWAF(t, deny)
 			app := startApp(t, greet)
-			_, out, server := startServer(t, servewaf.URL, app.URL, map[string]string{
+			_, out, server := startServer(t, standIn.URL, app.URL, map[string]string{
 				trustedProxies: localhost + "/32",
 			})
 
@@ -463,9 +509,9 @@ func TestAQuestionNamesNoZone(t *testing.T) {
 
 			server.Handler.ServeHTTP(httptest.NewRecorder(), req)
 
-			asked := servewaf.question(t)
-			if asked.header.Get(proxy.ClientHeader) != tc.client ||
-				asked.header.Get(proxy.PeerHeader) != tc.peer {
+			asked := standIn.question(t)
+			if asked.header.Get(servewaf.ClientHeader) != tc.client ||
+				asked.header.Get(servewaf.PeerHeader) != tc.peer {
 				t.Errorf("the question's headers are %v", asked.header)
 			}
 

internal/rproxy/request.go

@@ -16,9 +16,9 @@ import (
 	"sync/atomic"
 	"time"
 
-	"sneak.berlin/go/smallwebwaf/internal/proxy"
 	"sneak.berlin/go/smallwebwaf/internal/requestlog"
 	"sneak.berlin/go/smallwebwaf/internal/rules"
+	"sneak.berlin/go/smallwebwaf/internal/servewaf"
 )
 
 // flushAfterEachWrite has ReverseProxy pass on each part of the app's answer as
@@ -129,7 +129,7 @@ func (rq *request) readFirstPartOfBody() bool {
 	}
 
 	_ = rq.rc.SetReadDeadline(rq.requestDeadline())
-	held, err := io.ReadAll(io.LimitReader(rq.body, proxy.QuestionBodyMaxBytes))
+	held, err := io.ReadAll(io.LimitReader(rq.body, servewaf.QuestionBodyMaxBytes))
 	// From here on, the request timer ends a read of the rest of the body, so that
 	// the answer can name the side rproxy was waiting on.
 	_ = rq.rc.SetReadDeadline(time.Time{})
@@ -384,7 +384,7 @@ func (rq *request) finish(ctx context.Context) {
 		return
 	}
 
-	report := &proxy.Report{
+	report := &servewaf.Report{
 		RequestID:     rq.id,
 		Status:        min(rq.out.status, reportStatusMax),
 		RequestBytes:  requestBytes,

internal/rproxy/rproxy.go

@@ -22,7 +22,7 @@ import (
 	"time"
 
 	"sneak.berlin/go/smallwebwaf/internal/config"
-	"sneak.berlin/go/smallwebwaf/internal/proxy"
+	"sneak.berlin/go/smallwebwaf/internal/servewaf"
 )
 
 // How rproxy keeps connections to the app and to servewaf open between
@@ -85,7 +85,7 @@ func New(params Params) *Server {
 		transport:         newTransport(),
 		serveWAFTransport: newServeWAFTransport(),
 		reportURL: (&url.URL{
-			Scheme: backend.Scheme, Host: backend.Host, Path: proxy.ReportPath,
+			Scheme: backend.Scheme, Host: backend.Host, Path: servewaf.ReportPath,
 		}).String(),
 	}
 
@@ -166,7 +166,7 @@ func (h *handler) ServeHTTP(w http.ResponseWriter, r *http.Request) {
 	rq := h.newRequest(w, r)
 	defer rq.finish(r.Context())
 
-	if r.Method == http.MethodGet && r.URL.Path == proxy.HealthPath {
+	if r.Method == http.MethodGet && r.URL.Path == servewaf.HealthPath {
 		rq.answerHealth()
 
 		return
@@ -199,9 +199,9 @@ func (h *handler) ServeHTTP(w http.ResponseWriter, r *http.Request) {
 	rq.noteAnswer(answer)
 
 	switch rq.disposition {
-	case proxy.DispositionAllow:
+	case servewaf.DispositionAllow:
 		rq.passToApp(r.Context())
-	case proxy.DispositionClose:
+	case servewaf.DispositionClose:
 		// This panic has Go's server close the connection without an answer,
 		// and log nothing; the deferred finish still runs.
 		panic(http.ErrAbortHandler)

internal/rproxy/rproxy_test.go

@@ -19,9 +19,9 @@ import (
 	"time"
 
 	"sneak.berlin/go/smallwebwaf/internal/config"
-	"sneak.berlin/go/smallwebwaf/internal/proxy"
 	"sneak.berlin/go/smallwebwaf/internal/requestlog"
 	"sneak.berlin/go/smallwebwaf/internal/rproxy"
+	"sneak.berlin/go/smallwebwaf/internal/servewaf"
 )
 
 const (
@@ -54,7 +54,7 @@ const (
 
 // The headers the tests set and look at.
 const (
-	dispositionHeader    = proxy.DispositionHeader
+	dispositionHeader    = servewaf.DispositionHeader
 	forwardedForHeader   = "X-Forwarded-For"
 	forwardedProtoHeader = "X-Forwarded-Proto"
 	requestIDHeader      = "X-Request-ID"
@@ -70,9 +70,9 @@ const (
 
 // What the stand-in for servewaf answers.
 const (
-	dispositionAllow = proxy.DispositionAllow
-	dispositionDeny  = proxy.DispositionDeny
-	dispositionClose = proxy.DispositionClose
+	dispositionAllow = servewaf.DispositionAllow
+	dispositionDeny  = servewaf.DispositionDeny
+	dispositionClose = servewaf.DispositionClose
 	// deniedBody is the body of a deny.
 	deniedBody = "refused by servewaf"
 )
@@ -173,7 +173,7 @@ type serveWAF struct {
 	*httptest.Server
 
 	questions chan question
-	reports   chan proxy.Report
+	reports   chan servewaf.Report
 }
 
 // startServeWAF starts a stand-in for servewaf.
@@ -182,11 +182,11 @@ func startServeWAF(t *testing.T, answer http.HandlerFunc) *serveWAF {
 
 	s := &serveWAF{
 		questions: make(chan question, 10),
-		reports:   make(chan proxy.Report, 10),
+		reports:   make(chan servewaf.Report, 10),
 	}
 	s.Server = httptest.NewServer(http.HandlerFunc(
 		func(w http.ResponseWriter, r *http.Request) {
-			if r.Header.Get(proxy.ClientHeader) == "" {
+			if r.Header.Get(servewaf.ClientHeader) == "" {
 				s.takeReport(t, w, r)
 
 				return
@@ -213,10 +213,10 @@ func startServeWAF(t *testing.T, answer http.HandlerFunc) *serveWAF {
 func (s *serveWAF) takeReport(t *testing.T, w http.ResponseWriter, r *http.Request) {
 	t.Helper()
 
-	var report proxy.Report
+	var report servewaf.Report
 
 	err := json.NewDecoder(r.Body).Decode(&report)
-	if err != nil || r.Method != http.MethodPost || r.URL.Path != proxy.ReportPath {
+	if err != nil || r.Method != http.MethodPost || r.URL.Path != servewaf.ReportPath {
 		t.Errorf("%s %s is no report: %v", r.Method, r.URL.Path, err)
 	}
 
@@ -237,7 +237,7 @@ func (s *serveWAF) wantNoReport(t *testing.T) {
 }
 
 // report waits for a report.
-func (s *serveWAF) report(t *testing.T) proxy.Report {
+func (s *serveWAF) report(t *testing.T) servewaf.Report {
 	t.Helper()
 
 	select {
@@ -246,7 +246,7 @@ func (s *serveWAF) report(t *testing.T) proxy.Report {
 	case <-time.After(waitLimit):
 		t.Fatal("no report")
 
-		return proxy.Report{}
+		return servewaf.Report{}
 	}
 }
 
@@ -273,7 +273,7 @@ func startServeWAFAnsweringReports(
 
 	backend := httptest.NewServer(http.HandlerFunc(
 		func(w http.ResponseWriter, r *http.Request) {
-			if r.Header.Get(proxy.ClientHeader) != "" {
+			if r.Header.Get(servewaf.ClientHeader) != "" {
 				answer(w, r)
 
 				return
@@ -498,7 +498,7 @@ func readStatus(t *testing.T, conn net.Conn) int {
 func TestPassesAnAllowedRequestToTheAppAndItsAnswerBack(t *testing.T) {
 	t.Parallel()
 
-	servewaf := startServeWAF(t, func(w http.ResponseWriter, r *http.Request) {
+	standIn := startServeWAF(t, func(w http.ResponseWriter, r *http.Request) {
 		w.Header().Set(asnHeader, "AS64496")
 		w.Header().Set(countryHeader, "DE")
 		allow(w, r)
@@ -512,7 +512,7 @@ func TestPassesAnAllowedRequestToTheAppAndItsAnswerBack(t *testing.T) {
 		w.WriteHeader(http.StatusTeapot)
 		_, _ = io.WriteString(w, greeting)
 	})
-	addr, _ := startRProxy(t, servewaf.URL, app.URL, nil)
+	addr, _ := startRProxy(t, standIn.URL, app.URL, nil)
 
 	const target = pathGoReencodes + "?b=2&a=1&bad=%zz;x"
 
@@ -530,7 +530,7 @@ func TestPassesAnAllowedRequestToTheAppAndItsAnswerBack(t *testing.T) {
 	}
 
 	received := <-seen
-	asked := servewaf.question(t)
+	asked := standIn.question(t)
 
 	if received.RequestURI != target || received.Host != site {
 		t.Errorf("the app saw %s for %s", received.RequestURI, received.Host)
@@ -557,14 +557,14 @@ func TestAPeerNotTrustedHasItsForwardedHeadersReplaced(t *testing.T) {
 		"X-Forwarded-Tls-Client-Cert-Info", "X-Real-Ip",
 	}
 
-	servewaf := startServeWAF(t, allow)
+	standIn := startServeWAF(t, allow)
 	seen := make(chan http.Header, 1)
 	app := startApp(t, func(w http.ResponseWriter, r *http.Request) {
 		seen <- r.Header.Clone()
 
 		greet(w, r)
 	})
-	addr, _ := startRProxy(t, servewaf.URL, app.URL, map[string]string{
+	addr, _ := startRProxy(t, standIn.URL, app.URL, map[string]string{
 		trustedProxies: "10.0.0.0/8",
 	})
 
@@ -602,14 +602,14 @@ func TestAPeerNotTrustedHasItsForwardedHeadersReplaced(t *testing.T) {
 func TestATrustedProxysForwardedHeadersPassOn(t *testing.T) {
 	t.Parallel()
 
-	servewaf := startServeWAF(t, allow)
+	standIn := startServeWAF(t, allow)
 	seen := make(chan http.Header, 1)
 	app := startApp(t, func(w http.ResponseWriter, r *http.Request) {
 		seen <- r.Header.Clone()
 
 		greet(w, r)
 	})
-	addr, _ := startRProxy(t, servewaf.URL, app.URL, map[string]string{
+	addr, _ := startRProxy(t, standIn.URL, app.URL, map[string]string{
 		trustedProxies: localhost + "/32",
 	})
 
@@ -641,12 +641,12 @@ func TestATrustedProxysForwardedHeadersPassOn(t *testing.T) {
 func TestAnAnswerWithoutAContentTypeGetsNone(t *testing.T) {
 	t.Parallel()
 
-	servewaf := startServeWAF(t, allow)
+	standIn := startServeWAF(t, allow)
 	app := startApp(t, func(w http.ResponseWriter, _ *http.Request) {
 		w.Header()["Content-Type"] = nil
 		_, _ = io.WriteString(w, "<html>")
 	})
-	_, _, server := startServer(t, servewaf.URL, app.URL, nil)
+	_, _, server := startServer(t, standIn.URL, app.URL, nil)
 
 	req := httptest.NewRequestWithContext(t.Context(), http.MethodGet, "/", http.NoBody)
 	w := httptest.NewRecorder()
@@ -704,11 +704,11 @@ func TestRemovesTheVisitorsLookupHeadersWhenServeWAFGivesNone(t *testing.T) {
 func TestDenyGivesTheVisitorServeWAFsAnswer(t *testing.T) {
 	t.Parallel()
 
-	servewaf := startServeWAF(t, deny)
+	standIn := startServeWAF(t, deny)
 	app := startApp(t, func(http.ResponseWriter, *http.Request) {
 		t.Error("the app was asked")
 	})
-	addr, out := startRProxy(t, servewaf.URL, app.URL, nil)
+	addr, out := startRProxy(t, standIn.URL, app.URL, nil)
 
 	got := get(t, addr, "/")
 	if got.status != http.StatusForbidden || got.body != deniedBody ||
@@ -720,7 +720,7 @@ func TestDenyGivesTheVisitorServeWAFsAnswer(t *testing.T) {
 		t.Errorf("the visitor got %s", dispositionHeader)
 	}
 
-	report := servewaf.report(t)
+	report := standIn.report(t)
 	if report.Status != http.StatusForbidden ||
 		report.ResponseBytes != int64(len(deniedBody)) ||
 		report.DurationUpstreamTotal != 0 {
@@ -736,9 +736,9 @@ func TestDenyGivesTheVisitorServeWAFsAnswer(t *testing.T) {
 func TestADeniedHeadKeepsServeWAFsContentLength(t *testing.T) {
 	t.Parallel()
 
-	servewaf := startServeWAF(t, deny)
+	standIn := startServeWAF(t, deny)
 	app := startApp(t, greet)
-	addr, _ := startRProxy(t, servewaf.URL, app.URL, nil)
+	addr, _ := startRProxy(t, standIn.URL, app.URL, nil)
 
 	got := visit(t, newRequest(t, http.MethodHead, addr, "/", http.NoBody))
 	if got.status != http.StatusForbidden ||
@@ -758,15 +758,15 @@ func TestAnAnswerRProxyHoldsWholeIsSentBeforeItsLogLine(t *testing.T) {
 	}{
 		{"a deny", "GET /" + host, deniedBody, http.StatusForbidden},
 		{"rproxy's own answer", "GET x:admin" + host, "Bad Request\n", http.StatusBadRequest},
-		{"the health check", "GET " + proxy.HealthPath + host, "ok\n", http.StatusOK},
+		{"the health check", "GET " + servewaf.HealthPath + host, "ok\n", http.StatusOK},
 	} {
 		t.Run(tc.name, func(t *testing.T) {
 			t.Parallel()
 
 			log := heldLog{release: make(chan struct{})}
-			servewaf := startServeWAF(t, deny)
+			standIn := startServeWAF(t, deny)
 			app := startApp(t, greet)
-			addr, _ := startServerLogging(t, servewaf.URL, app.URL, nil, log, io.Discard)
+			addr, _ := startServerLogging(t, standIn.URL, app.URL, nil, log, io.Discard)
 
 			t.Cleanup(func() { close(log.release) })
 
@@ -794,9 +794,9 @@ func TestAnAnswerRProxyHoldsWholeIsSentBeforeItsLogLine(t *testing.T) {
 func TestRProxysOwnAnswerIsPlainText(t *testing.T) {
 	t.Parallel()
 
-	servewaf := startServeWAF(t, allow)
+	standIn := startServeWAF(t, allow)
 	app := startApp(t, greet)
-	addr, _ := startRProxy(t, servewaf.URL, app.URL, nil)
+	addr, _ := startRProxy(t, standIn.URL, app.URL, nil)
 
 	conn := dial(t, addr)
 	send(t, conn, "GET x:admin HTTP/1.1\r\nHost: site.example\r\n\r\n")
@@ -817,14 +817,14 @@ func TestRProxysOwnAnswerIsPlainText(t *testing.T) {
 func TestCloseClosesTheConnectionWithoutAnAnswer(t *testing.T) {
 	t.Parallel()
 
-	servewaf := startServeWAF(t, func(w http.ResponseWriter, _ *http.Request) {
+	standIn := startServeWAF(t, func(w http.ResponseWriter, _ *http.Request) {
 		w.Header().Set(dispositionHeader, dispositionClose)
 		w.WriteHeader(http.StatusOK)
 	})
 	app := startApp(t, func(http.ResponseWriter, *http.Request) {
 		t.Error("the app was asked")
 	})
-	addr, out := startRProxy(t, servewaf.URL, app.URL, nil)
+	addr, out := startRProxy(t, standIn.URL, app.URL, nil)
 
 	conn := dial(t, addr)
 	send(t, conn, "GET / HTTP/1.1\r\nHost: site.example\r\n\r\n")
@@ -835,7 +835,7 @@ func TestCloseClosesTheConnectionWithoutAnAnswer(t *testing.T) {
 			text, err)
 	}
 
-	report := servewaf.report(t)
+	report := standIn.report(t)
 	if report.Status != 0 || report.ResponseBytes != 0 {
 		t.Errorf("report %+v, of a visitor sent nothing", report)
 	}
@@ -935,7 +935,7 @@ func TestAnAnswerOtherThanAllowGoesToTheVisitorAsServeWAFGaveIt(t *testing.T) {
 			t.Run(tc.name+" with the default "+setting, func(t *testing.T) {
 				t.Parallel()
 
-				servewaf := startServeWAF(t, func(w http.ResponseWriter, _ *http.Request) {
+				standIn := startServeWAF(t, func(w http.ResponseWriter, _ *http.Request) {
 					if tc.disposition != "" {
 						w.Header().Set(dispositionHeader, tc.disposition)
 					}
@@ -947,7 +947,7 @@ func TestAnAnswerOtherThanAllowGoesToTheVisitorAsServeWAFGaveIt(t *testing.T) {
 				app := startApp(t, func(http.ResponseWriter, *http.Request) {
 					t.Error("the app was asked")
 				})
-				addr, out := startRProxy(t, servewaf.URL, app.URL, map[string]string{
+				addr, out := startRProxy(t, standIn.URL, app.URL, map[string]string{
 					defaultDisposition: setting,
 				})
 
@@ -977,11 +977,11 @@ func TestAnAnswerOtherThanAllowGoesToTheVisitorAsServeWAFGaveIt(t *testing.T) {
 func TestAnAnswerWithoutAValidDispositionGetsNoReport(t *testing.T) {
 	t.Parallel()
 
-	servewaf := startServeWAF(t, func(w http.ResponseWriter, _ *http.Request) {
+	standIn := startServeWAF(t, func(w http.ResponseWriter, _ *http.Request) {
 		http.Error(w, "refused", http.StatusBadRequest)
 	})
 	app := startApp(t, greet)
-	addr, out := startRProxy(t, servewaf.URL, app.URL, nil)
+	addr, out := startRProxy(t, standIn.URL, app.URL, nil)
 
 	if got := get(t, addr, "/"); got.status != http.StatusBadRequest {
 		t.Errorf("answered %+v, want servewaf's 400", got)
@@ -991,18 +991,18 @@ func TestAnAnswerWithoutAValidDispositionGetsNoReport(t *testing.T) {
 		t.Errorf("line %v, want no disposition", line)
 	}
 
-	servewaf.wantNoReport(t)
+	standIn.wantNoReport(t)
 }
 
 func TestAnAnswerWithoutAContentTypeGoesToTheVisitorWithNone(t *testing.T) {
 	t.Parallel()
 
-	servewaf := startServeWAF(t, func(w http.ResponseWriter, _ *http.Request) {
+	standIn := startServeWAF(t, func(w http.ResponseWriter, _ *http.Request) {
 		w.Header()["Content-Type"] = nil
 		w.WriteHeader(http.StatusInternalServerError)
 		_, _ = io.WriteString(w, "<html>broken")
 	})
-	addr, _ := startRProxy(t, servewaf.URL, nowhere, nil)
+	addr, _ := startRProxy(t, standIn.URL, nowhere, nil)
 
 	got := get(t, addr, "/")
 	if contentType, sent := got.header["Content-Type"]; sent {
@@ -1015,11 +1015,11 @@ func TestAnAnswerOf1MiBGoesToTheVisitor(t *testing.T) {
 
 	const size = 1 << 20
 
-	servewaf := startServeWAF(t, func(w http.ResponseWriter, _ *http.Request) {
+	standIn := startServeWAF(t, func(w http.ResponseWriter, _ *http.Request) {
 		w.WriteHeader(http.StatusInternalServerError)
 		_, _ = w.Write(make([]byte, size))
 	})
-	addr, _ := startRProxy(t, servewaf.URL, nowhere, nil)
+	addr, _ := startRProxy(t, standIn.URL, nowhere, nil)
 
 	got := get(t, addr, "/")
 	if got.status != http.StatusInternalServerError || len(got.body) != size {
@@ -1135,15 +1135,15 @@ func TestAnAnswerThatCannotBePassedOnIsAnswered502(t *testing.T) {
 func TestAnAnswerThatCannotBePassedOnGetsNoReport(t *testing.T) {
 	t.Parallel()
 
-	servewaf := startServeWAF(t, overOneMiB(dispositionDeny))
-	addr, out := startRProxy(t, servewaf.URL, nowhere, nil)
+	standIn := startServeWAF(t, overOneMiB(dispositionDeny))
+	addr, out := startRProxy(t, standIn.URL, nowhere, nil)
 
 	if got := get(t, addr, "/"); got.status != http.StatusBadGateway {
 		t.Errorf("answered %+v, want 502", got)
 	}
 
 	out.requestLine(t)
-	servewaf.wantNoReport(t)
+	standIn.wantNoReport(t)
 }
 
 func TestWithoutAnAnswerTheDefaultDispositionDecides(t *testing.T) {
@@ -1199,20 +1199,20 @@ func TestAVisitorThatGoesAwayWhileServeWAFIsAskedGetsNoDefault(t *testing.T) {
 		t.Run("with the default "+disposition, func(t *testing.T) {
 			t.Parallel()
 
-			servewaf := startServeWAF(t, func(_ http.ResponseWriter, r *http.Request) {
+			standIn := startServeWAF(t, func(_ http.ResponseWriter, r *http.Request) {
 				<-r.Context().Done()
 			})
 			app := startApp(t, func(http.ResponseWriter, *http.Request) {
 				t.Error("the app was asked")
 			})
-			addr, out := startRProxy(t, servewaf.URL, app.URL, map[string]string{
+			addr, out := startRProxy(t, standIn.URL, app.URL, map[string]string{
 				timeoutSetting:     "60000",
 				defaultDisposition: disposition,
 			})
 
 			conn := dial(t, addr)
 			send(t, conn, "GET / HTTP/1.1\r\nHost: site.example\r\n\r\n")
-			servewaf.question(t)
+			standIn.question(t)
 
 			_ = conn.Close()
 
@@ -1226,7 +1226,7 @@ func TestAVisitorThatGoesAwayWhileServeWAFIsAskedGetsNoDefault(t *testing.T) {
 				t.Error("rproxy warned that servewaf gave no answer")
 			}
 
-			servewaf.wantNoReport(t)
+			standIn.wantNoReport(t)
 		})
 	}
 }
@@ -1244,17 +1244,17 @@ func TestRProxyWarnsWhenTheDefaultDecides(t *testing.T) {
 func TestSendsNoReportWithoutAnAnswer(t *testing.T) {
 	t.Parallel()
 
-	servewaf := startServeWAF(t, func(_ http.ResponseWriter, r *http.Request) {
+	standIn := startServeWAF(t, func(_ http.ResponseWriter, r *http.Request) {
 		<-r.Context().Done()
 	})
 	app := startApp(t, greet)
-	addr, out := startRProxy(t, servewaf.URL, app.URL, map[string]string{
+	addr, out := startRProxy(t, standIn.URL, app.URL, map[string]string{
 		timeoutSetting: "200",
 	})
 
 	wantGreeting(t, get(t, addr, "/"))
 	out.requestLine(t)
-	servewaf.wantNoReport(t)
+	standIn.wantNoReport(t)
 }
 
 func TestAPathUnderOwnPrefixNeverReachesTheApp(t *testing.T) {
@@ -1274,25 +1274,25 @@ func TestAPathUnderOwnPrefixNeverReachesTheApp(t *testing.T) {
 func TestHealthCheckIsAnsweredWhileServeWAFIsDown(t *testing.T) {
 	t.Parallel()
 
-	servewaf := startServeWAF(t, allow)
+	standIn := startServeWAF(t, allow)
 	app := startApp(t, greet)
 	addr, out := startRProxy(t, nowhere, app.URL, nil)
 
-	got := get(t, addr, proxy.HealthPath)
+	got := get(t, addr, servewaf.HealthPath)
 	if got.status != http.StatusOK || got.body != "ok\n" {
 		t.Errorf("answered %+v, want ok", got)
 	}
 
 	line := out.requestLine(t)
-	if line["path"] != proxy.HealthPath || line["disposition"] != nil {
+	if line["path"] != servewaf.HealthPath || line["disposition"] != nil {
 		t.Errorf("line %v, want one with no disposition", line)
 	}
 
 	// With servewaf up too, it is not asked.
-	addr, _ = startRProxy(t, servewaf.URL, app.URL, nil)
-	get(t, addr, proxy.HealthPath)
+	addr, _ = startRProxy(t, standIn.URL, app.URL, nil)
+	get(t, addr, servewaf.HealthPath)
 
-	if len(servewaf.questions) != 0 {
+	if len(standIn.questions) != 0 {
 		t.Error("servewaf was asked about the health check")
 	}
 }
@@ -1353,8 +1353,10 @@ func TestAReportServeWAFLeavesUnansweredIsDroppedAtTheTimeLimit(t *testing.T) {
 		})
 
 	app := startApp(t, greet)
+	// The time limit is long enough for a loaded host to answer the question before
+	// it runs out.
 	addr, out := startRProxy(t, backend, app.URL, map[string]string{
-		timeoutSetting: "1000",
+		timeoutSetting: "3000",
 	})
 
 	t.Cleanup(func() { close(release) })
@@ -1394,15 +1396,15 @@ func TestAReportAnswered101IsDroppedAtOnce(t *testing.T) {
 func TestAReportDueAfterWaitForReportsIsDropped(t *testing.T) {
 	t.Parallel()
 
-	servewaf := startServeWAF(t, allow)
+	standIn := startServeWAF(t, allow)
 	app := startApp(t, greet)
-	addr, out, server := startServer(t, servewaf.URL, app.URL, nil)
+	addr, out, server := startServer(t, standIn.URL, app.URL, nil)
 
 	server.WaitForReports()
 
 	wantGreeting(t, get(t, addr, "/"))
 	out.requestLine(t)
-	servewaf.wantNoReport(t)
+	standIn.wantNoReport(t)
 }
 
 func TestReportGivesWhatHappened(t *testing.T) {
@@ -1410,14 +1412,14 @@ func TestReportGivesWhatHappened(t *testing.T) {
 
 	const body = "the visitor's body"
 
-	servewaf := startServeWAF(t, allow)
+	standIn := startServeWAF(t, allow)
 	app := startApp(t, greet)
-	addr, out := startRProxy(t, servewaf.URL, app.URL, nil)
+	addr, out := startRProxy(t, standIn.URL, app.URL, nil)
 
 	wantGreeting(t, visit(t, newRequest(t, http.MethodPost, addr, "/",
 		strings.NewReader(body))))
 
-	report := servewaf.report(t)
+	report := standIn.report(t)
 
 	if report.RequestID == "" || report.Status != http.StatusOK ||
 		report.RequestBytes != int64(len(body)) ||
@@ -1440,7 +1442,7 @@ func TestWaitForReportsWaitsForAReportBeingSent(t *testing.T) {
 	release := make(chan struct{})
 	backend := httptest.NewServer(http.HandlerFunc(
 		func(w http.ResponseWriter, r *http.Request) {
-			if r.Header.Get(proxy.ClientHeader) != "" {
+			if r.Header.Get(servewaf.ClientHeader) != "" {
 				allow(w, r)
 
 				return
@@ -1495,9 +1497,9 @@ func TestWaitForReportsWaitsForAReportBeingSent(t *testing.T) {
 func TestReportOfAWebSocketCountsWhatItCarried(t *testing.T) {
 	t.Parallel()
 
-	servewaf := startServeWAF(t, allow)
+	standIn := startServeWAF(t, allow)
 	app := startApp(t, echoAfterUpgrade)
-	addr, out := startRProxy(t, servewaf.URL, app.URL, map[string]string{
+	addr, out := startRProxy(t, standIn.URL, app.URL, map[string]string{
 		maxRequestTime:  "2000",
 		maxResponseTime: "2000",
 	})
@@ -1533,7 +1535,7 @@ func TestReportOfAWebSocketCountsWhatItCarried(t *testing.T) {
 
 	_ = conn.Close()
 
-	report := servewaf.report(t)
+	report := standIn.report(t)
 	if report.Status != http.StatusSwitchingProtocols ||
 		report.RequestBytes != int64(len(message)) ||
 		report.ResponseBytes != int64(len(message)) {
@@ -1550,7 +1552,7 @@ func TestAWebSocketPassesOnThatTheVisitorStoppedSending(t *testing.T) {
 
 	const goodbye = "sent after the visitor stopped sending\n"
 
-	servewaf := startServeWAF(t, allow)
+	standIn := startServeWAF(t, allow)
 	app := startApp(t, func(w http.ResponseWriter, _ *http.Request) {
 		conn, buffered, err := http.NewResponseController(w).Hijack()
 		if err != nil {
@@ -1570,7 +1572,7 @@ func TestAWebSocketPassesOnThatTheVisitorStoppedSending(t *testing.T) {
 		_, _ = buffered.WriteString(goodbye)
 		_ = buffered.Flush()
 	})
-	addr, _ := startRProxy(t, servewaf.URL, app.URL, nil)
+	addr, _ := startRProxy(t, standIn.URL, app.URL, nil)
 
 	conn := dial(t, addr)
 	send(t, conn, "GET /socket HTTP/1.1\r\nHost: app\r\n"+
@@ -1608,7 +1610,7 @@ func TestAWebSocketPassesOnThatTheVisitorStoppedSending(t *testing.T) {
 //nolint:paralleltest // see above
 func TestASwitchNotPassedOnClosesTheAppsConnection(t *testing.T) {
 	closed := make(chan error, 1)
-	servewaf := startServeWAF(t, allow)
+	standIn := startServeWAF(t, allow)
 	app := startApp(t, func(w http.ResponseWriter, _ *http.Request) {
 		conn, buffered, err := http.NewResponseController(w).Hijack()
 		if err != nil {
@@ -1631,7 +1633,7 @@ func TestASwitchNotPassedOnClosesTheAppsConnection(t *testing.T) {
 		_, err = buffered.ReadByte()
 		closed <- err
 	})
-	addr, _ := startRProxy(t, servewaf.URL, app.URL, nil)
+	addr, _ := startRProxy(t, standIn.URL, app.URL, nil)
 
 	conn := dial(t, addr)
 	send(t, conn, "GET /socket HTTP/1.1\r\nHost: app\r\n"+
@@ -1679,9 +1681,9 @@ func TestEachRequestGetsAFreshID(t *testing.T) {
 
 	const fromTraefik = "an-id-from-traefik"
 
-	servewaf := startServeWAF(t, allow)
+	standIn := startServeWAF(t, allow)
 	app := startApp(t, greet)
-	addr, _ := startRProxy(t, servewaf.URL, app.URL, map[string]string{
+	addr, _ := startRProxy(t, standIn.URL, app.URL, map[string]string{
 		trustedProxies: localhost + "/32",
 	})
 
@@ -1692,7 +1694,7 @@ func TestEachRequestGetsAFreshID(t *testing.T) {
 		req.Header.Set(requestIDHeader, fromTraefik)
 		wantGreeting(t, visit(t, req))
 
-		ids = append(ids, servewaf.question(t).header.Get(requestIDHeader))
+		ids = append(ids, standIn.question(t).header.Get(requestIDHeader))
 	}
 
 	if slices.Contains(ids, fromTraefik) || ids[0] == "" || ids[0] == ids[1] {
@@ -1709,16 +1711,16 @@ func TestLogLineGivesTheRequestAsSent(t *testing.T) {
 		body  = "the visitor's body"
 	)
 
-	servewaf := startServeWAF(t, allow)
+	standIn := startServeWAF(t, allow)
 	app := startApp(t, greet)
-	addr, out := startRProxy(t, servewaf.URL, app.URL, nil)
+	addr, out := startRProxy(t, standIn.URL, app.URL, nil)
 
 	req := newRequest(t, http.MethodPost, addr, path+"?"+query, strings.NewReader(body))
 	req.Host = site
 	wantGreeting(t, visit(t, req))
 
 	line := out.requestLine(t)
-	asked := servewaf.question(t)
+	asked := standIn.question(t)
 
 	for name, want := range map[string]any{
 		"type":           "request",

internal/rproxy/servewaf.go

@@ -11,7 +11,7 @@ import (
 	"net/http"
 	"strings"
 
-	"sneak.berlin/go/smallwebwaf/internal/proxy"
+	"sneak.berlin/go/smallwebwaf/internal/servewaf"
 )
 
 // answerBodyMaxBytes is the most of the body of servewaf's answer that is read.
@@ -38,10 +38,10 @@ type servewafAnswer struct {
 // notes nothing, and no report is due for it: servewaf holds no decision to report
 // on.
 func (rq *request) noteAnswer(answer *servewafAnswer) {
-	disposition := answer.header.Get(proxy.DispositionHeader)
+	disposition := answer.header.Get(servewaf.DispositionHeader)
 
 	switch disposition {
-	case proxy.DispositionAllow, proxy.DispositionDeny, proxy.DispositionClose:
+	case servewaf.DispositionAllow, servewaf.DispositionDeny, servewaf.DispositionClose:
 		rq.disposition = disposition
 		rq.answered = true
 		rq.asn = answer.header.Get(asnHeader)
@@ -74,7 +74,7 @@ func (rq *request) handleNoUsableAnswer(ctx context.Context, err error) {
 		rq.disposition = rq.h.config.DefaultDisposition
 		rq.byDefault = true
 
-		if rq.disposition == proxy.DispositionAllow {
+		if rq.disposition == servewaf.DispositionAllow {
 			rq.passToApp(ctx)
 		} else {
 			rq.answer(http.StatusServiceUnavailable)
@@ -169,13 +169,13 @@ func (rq *request) newQuestion(ctx context.Context) (*http.Request, error) {
 	question.TransferEncoding = in.TransferEncoding
 
 	question.Header = in.Header.Clone()
-	question.Header.Set(proxy.ClientHeader, rq.client.String())
-	question.Header.Set(proxy.PeerHeader, rq.peer.String())
-	question.Header.Del(proxy.ContentLengthHeader)
+	question.Header.Set(servewaf.ClientHeader, rq.client.String())
+	question.Header.Set(servewaf.PeerHeader, rq.peer.String())
+	question.Header.Del(servewaf.ContentLengthHeader)
 
 	announced := in.Header.Get("Content-Length")
 	if announced != "" {
-		question.Header.Set(proxy.ContentLengthHeader, announced)
+		question.Header.Set(servewaf.ContentLengthHeader, announced)
 	}
 
 	question.Header.Set(requestIDHeader, rq.id)
@@ -196,7 +196,7 @@ func (rq *request) answerWith(answer *servewafAnswer) {
 
 	header := rq.out.Header()
 	maps.Copy(header, answer.header)
-	header.Del(proxy.DispositionHeader)
+	header.Del(servewaf.DispositionHeader)
 
 	// Go's server adds a Content-Type it guesses from the body to a response whose
 	// headers have no Content-Type key. The key with no value sends none.
@@ -210,7 +210,7 @@ func (rq *request) answerWith(answer *servewafAnswer) {
 // sendReport sends servewaf report on a goroutine of its own, so that the
 // visitor does not wait for it. The report goes on after ctx, the request's own
 // context, has ended.
-func (h *handler) sendReport(ctx context.Context, report *proxy.Report) {
+func (h *handler) sendReport(ctx context.Context, report *servewaf.Report) {
 	h.reportsMu.Lock()
 	defer h.reportsMu.Unlock()
 
@@ -228,7 +228,7 @@ func (h *handler) sendReport(ctx context.Context, report *proxy.Report) {
 
 // postReport posts report to servewaf, and waits for its answer for up to
 // SWRP_TIMEOUT_MS.
-func (h *handler) postReport(ctx context.Context, report *proxy.Report) error {
+func (h *handler) postReport(ctx context.Context, report *servewaf.Report) error {
 	body, err := json.Marshal(report)
 	if err != nil {
 		return fmt.Errorf("encode the report: %w", err)

internal/servewaf/abuseipdb.go

@@ -0,0 +1,55 @@
+package servewaf
+
+// The heuristic abuseipdb. It reads SWWAF_ABUSEIPDB_KEY,
+// SWWAF_ABUSEIPDB_MIN_SCORE and SWWAF_REPUTATION_ACTION.
+
+import (
+	"context"
+	"time"
+
+	"sneak.berlin/go/smallwebwaf/internal/bans"
+	"sneak.berlin/go/smallwebwaf/internal/ratelimit"
+	"sneak.berlin/go/smallwebwaf/internal/reputation"
+	"sneak.berlin/go/smallwebwaf/internal/requestlog"
+)
+
+// abuseIPDB notes AbuseIPDB, as noteHit does, with the score, when its score
+// of the client is a hit, and refuses the request when SWWAF_REPUTATION_ACTION
+// is deny, as dnsbl does for a zone. While SWWAF_ABUSEIPDB_KEY is unset it does
+// nothing. A client without a score is checked in the background, by the
+// request's address, if its history counts an offence, and the request does
+// not wait for the answer. The score is then used for each address of the
+// client. Its figures are the score and SWWAF_ABUSEIPDB_MIN_SCORE.
+type abuseIPDB struct{}
+
+func (abuseIPDB) name() string { return "abuseipdb" }
+
+func (abuseIPDB) check(ctx context.Context, rq *request, _ time.Time) *verdict {
+	if rq.h.config.AbuseIPDBKey == "" {
+		return nil
+	}
+
+	client := rq.h.clientGroup(rq.client)
+	held, _ := rq.h.limiter.Client(client)
+	offender := held.History.Offences != ratelimit.Offences{}
+
+	score, hit := rq.h.abuseIPDB.Hit(ctx, client, rq.client, offender)
+	if !hit {
+		return nil
+	}
+
+	rq.abuseIPDBHit = true
+	rq.noteHit(bans.ReputationHit{Source: reputation.AbuseIPDBSource, Score: &score},
+		"scored by AbuseIPDB at or over SWWAF_ABUSEIPDB_MIN_SCORE")
+
+	if rq.h.config.ReputationAction != deny {
+		return nil
+	}
+
+	return &verdict{
+		action: requestlog.ActionDenied,
+		figures: map[string]any{
+			figureScore: score, "min_score": rq.h.config.AbuseIPDBMinScore,
+		},
+	}
+}

internal/servewaf/admin.go

@@ -1,4 +1,4 @@
-package proxy
+package servewaf
 
 import (
 	"bytes"
@@ -9,7 +9,6 @@ import (
 	"io"
 	"net/http"
 	"net/netip"
-	"os"
 	"strings"
 	"time"
 
@@ -50,16 +49,13 @@ func (rq *request) answerHealth() {
 	_, _ = io.WriteString(rq.out, "ok\n")
 }
 
-// answerAdmin answers a request for smallwebwaf itself, under
-// /_smallwebwaf/, once it has passed the checks. Each endpoint needs a
-// token, sent as Authorization: Bearer <token>: the metrics
-// SWWAF_METRICS_TOKEN, the others SWWAF_ADMIN_TOKEN. A request without
-// it is refused with 401, which counts toward the error burst. An
-// endpoint whose token is unset answers 404, as any other request under
-// /_smallwebwaf/ does.
+// answerAdmin answers a request for one of servewaf's own endpoints. Each
+// needs a token, sent as Authorization: Bearer <token>: the metrics
+// SWWAF_METRICS_TOKEN, the others SWWAF_ADMIN_TOKEN. A request without it is
+// refused with 401. An endpoint whose token is unset answers 404, as any other
+// path does.
 func (rq *request) answerAdmin() {
 	rq.line.Action = requestlog.ActionAdmin
-	rq.startClientResponseTimeout()
 
 	token, answer := rq.endpoint()
 
@@ -67,12 +63,8 @@ func (rq *request) answerAdmin() {
 	case token == "":
 		http.Error(rq.out, http.StatusText(http.StatusNotFound), http.StatusNotFound)
 	case !hasToken(rq.in, token):
-		rq.tokenRefused = true
 		rq.out.Header().Set("WWW-Authenticate", "Bearer")
-		rq.answer(refusal{
-			status: http.StatusUnauthorized,
-			action: requestlog.ActionAdmin,
-		})
+		http.Error(rq.out, http.StatusText(http.StatusUnauthorized), http.StatusUnauthorized)
 	default:
 		answer()
 	}
@@ -129,26 +121,7 @@ type banToAdd struct {
 // an admin, from now for the duration the body gives, with its reason,
 // and answers with that ban.
 func (rq *request) addBan() {
-	// The body must arrive within SWWAF_CLIENT_REQUEST_TIMEOUT, as any
-	// other request's must.
-	rq.stopReadingBody(rq.clientRequestDeadline())
-
 	toAdd, err := rq.readBanToAdd()
-	if refused := rq.refused.Load(); refused != nil {
-		rq.answer(*refused) // the body is over SWWAF_REQUEST_MAX_BYTES
-
-		return
-	}
-
-	if errors.Is(err, os.ErrDeadlineExceeded) {
-		rq.answer(refusal{
-			status: http.StatusRequestTimeout,
-			action: requestlog.ActionTimedOut,
-			limit:  "SWWAF_CLIENT_REQUEST_TIMEOUT",
-		})
-
-		return
-	}
 
 	var (
 		netblock netip.Prefix
@@ -177,12 +150,9 @@ func (rq *request) addBan() {
 // readBanToAdd reads the body of POST BansPath: a JSON object with
 // nothing but whitespace after it, in at most banBodyMaxBytes.
 func (rq *request) readBanToAdd() (banToAdd, error) {
-	var body io.ReadCloser = http.NoBody
-	if rq.body != nil {
-		body = rq.body
-	}
+	data, err := io.ReadAll(http.MaxBytesReader(nil, rq.in.Body, banBodyMaxBytes))
+	rq.requestBytes = int64(len(data))
 
-	data, err := io.ReadAll(http.MaxBytesReader(nil, body, banBodyMaxBytes))
 	if err != nil {
 		return banToAdd{}, fmt.Errorf("%w: %w", errNotBanToAdd, err)
 	}
@@ -280,9 +250,9 @@ type clientAnswer struct {
 	Bans   []state.BanEntry  `json:"bans"`
 }
 
-// showClient answers GET ClientsPath<ip> with what smallwebwaf knows of
-// the client: its counters, its history, which holds its country as last
-// looked up and its offences, and its bans with their notes.
+// showClient answers GET ClientsPath<ip> with what servewaf knows of the client:
+// its counters, its history, which holds its country as last looked up and its
+// offences, and its bans with their notes.
 func (rq *request) showClient() {
 	addr, err := pathAddress(rq.in.URL.Path, ClientsPath)
 	if err != nil {

internal/servewaf/admin_test.go

@@ -1,19 +1,18 @@
-package proxy_test
+package servewaf_test
 
 import (
 	"encoding/json"
 	"net/http"
 	"net/netip"
 	"reflect"
-	"strconv"
 	"strings"
 	"testing"
 	"time"
 
 	"sneak.berlin/go/smallwebwaf/internal/bans"
-	"sneak.berlin/go/smallwebwaf/internal/proxy"
 	"sneak.berlin/go/smallwebwaf/internal/ratelimit"
 	"sneak.berlin/go/smallwebwaf/internal/requestlog"
+	"sneak.berlin/go/smallwebwaf/internal/servewaf"
 	"sneak.berlin/go/smallwebwaf/internal/state"
 )
 
@@ -23,8 +22,6 @@ const (
 	// how a request carries it.
 	adminSecret = "fedcba9876543210fedcba9876543210"
 	adminBearer = "Bearer " + adminSecret
-	// adminClient is the client the tests' admin sends its requests from.
-	adminClient = "192.0.2.10"
 	// banOtherClient is the body of a request to ban otherClient for an
 	// hour.
 	banOtherClient = `{"netblock": "` + otherClient + `", "duration": "1h", ` +
@@ -43,8 +40,7 @@ func TestAdminEndpointsAreOffWhileTheTokenIsUnset(t *testing.T) {
 	// An empty token does not match the unset one either.
 	for _, authorization := range []string{adminBearer, bearer, "Bearer ", ""} {
 		for _, e := range adminEndpoints() {
-			s.adminRequest(adminClient, authorization, e.method, e.path, e.body,
-				http.StatusNotFound, requestlog.ActionAdmin)
+			s.adminRequest(authorization, e.method, e.path, e.body, http.StatusNotFound)
 		}
 	}
 
@@ -71,8 +67,8 @@ func TestAdminEndpointsNeedTheAdminToken(t *testing.T) {
 		for _, authorization := range []string{
 			"", bearer, "Bearer " + strings.ToUpper(adminSecret), "Basic " + adminSecret,
 		} {
-			got := s.adminRequest(adminClient, authorization, e.method, e.path, e.body,
-				http.StatusUnauthorized, requestlog.ActionAdmin)
+			got := s.adminRequest(authorization, e.method, e.path, e.body,
+				http.StatusUnauthorized)
 			if got.header.Get("WWW-Authenticate") != "Bearer" {
 				t.Errorf("%s %s with %q was answered without WWW-Authenticate: Bearer",
 					e.method, e.path, authorization)
@@ -92,11 +88,11 @@ func TestAdminEndpointsNeedTheAdminToken(t *testing.T) {
 
 	// Any other request under /_smallwebwaf/ is not found.
 	for _, e := range []adminEndpoint{
-		{http.MethodPut, proxy.BansPath, banOtherClient},
-		{http.MethodDelete, proxy.BansPath, ""},
-		{http.MethodGet, proxy.BansPath + "/" + otherClient, ""},
-		{http.MethodPost, proxy.ClientsPath + otherClient, ""},
-		{http.MethodGet, strings.TrimSuffix(proxy.ClientsPath, "/"), ""},
+		{http.MethodPut, servewaf.BansPath, banOtherClient},
+		{http.MethodDelete, servewaf.BansPath, ""},
+		{http.MethodGet, servewaf.BansPath + "/" + otherClient, ""},
+		{http.MethodPost, servewaf.ClientsPath + otherClient, ""},
+		{http.MethodGet, strings.TrimSuffix(servewaf.ClientsPath, "/"), ""},
 	} {
 		s.admin(e.method, e.path, e.body, http.StatusNotFound)
 	}
@@ -122,7 +118,7 @@ func TestBanAddedListedAndLiftedThroughTheEndpoints(t *testing.T) {
 		Reason:   "probes for logins",
 	}
 
-	wantBans(t, s.admin(http.MethodPost, proxy.BansPath, banOtherClient, http.StatusOK),
+	wantBans(t, s.admin(http.MethodPost, servewaf.BansPath, banOtherClient, http.StatusOK),
 		want)
 
 	line := s.get(client, http.StatusForbidden, requestlog.ActionBanned)
@@ -133,7 +129,7 @@ func TestBanAddedListedAndLiftedThroughTheEndpoints(t *testing.T) {
 	// Its notes count the request it refused.
 	want.Notes.Requests, want.Notes.Refused = 1, 1
 
-	wantBans(t, s.admin(http.MethodGet, proxy.BansPath, "", http.StatusOK), want)
+	wantBans(t, s.admin(http.MethodGet, servewaf.BansPath, "", http.StatusOK), want)
 
 	// Ten minutes on, lifting the bans on client lifts that one, which is
 	// kept, marked lifted.
@@ -142,13 +138,13 @@ func TestBanAddedListedAndLiftedThroughTheEndpoints(t *testing.T) {
 	lifted := clk.Now()
 	want.Lifted = &lifted
 
-	wantBans(t, s.admin(http.MethodDelete, proxy.BansPath+"/"+client, "",
+	wantBans(t, s.admin(http.MethodDelete, servewaf.BansPath+"/"+client, "",
 		http.StatusOK), want)
 	s.get(client, http.StatusOK, requestlog.ActionForward)
-	wantBans(t, s.admin(http.MethodGet, proxy.BansPath, "", http.StatusOK), want)
+	wantBans(t, s.admin(http.MethodGet, servewaf.BansPath, "", http.StatusOK), want)
 
 	// No ban on it is active any more.
-	s.admin(http.MethodDelete, proxy.BansPath+"/"+client, "", http.StatusNotFound)
+	s.admin(http.MethodDelete, servewaf.BansPath+"/"+client, "", http.StatusNotFound)
 }
 
 func TestBanToAddGivesItsNetblockAndDuration(t *testing.T) {
@@ -185,7 +181,7 @@ func TestBanToAddGivesItsNetblockAndDuration(t *testing.T) {
 			want.Expires = &expires
 		}
 
-		wantBans(t, s.admin(http.MethodPost, proxy.BansPath, body, http.StatusOK), want)
+		wantBans(t, s.admin(http.MethodPost, servewaf.BansPath, body, http.StatusOK), want)
 	}
 }
 
@@ -254,7 +250,7 @@ func TestBanToAddThatCannotBeReadIsRefused(t *testing.T) {
 			"request body too large",
 		},
 	} {
-		got := s.admin(http.MethodPost, proxy.BansPath, tc.body, http.StatusBadRequest)
+		got := s.admin(http.MethodPost, servewaf.BansPath, tc.body, http.StatusBadRequest)
 		if !strings.Contains(string(got.body), tc.want) {
 			t.Errorf("%.80s was answered %q, want it to say %q", tc.body, got.body, tc.want)
 		}
@@ -265,64 +261,12 @@ func TestBanToAddThatCannotBeReadIsRefused(t *testing.T) {
 	}
 }
 
-func TestBanToAddOverTheRequestSizeLimitIsRefused(t *testing.T) {
-	t.Parallel()
-
-	s, _, server := startWithClock(t, "", map[string]string{
-		adminToken:      adminSecret,
-		requestMaxBytes: "16",
-	})
-
-	// Sent in a chunk, its length is not announced, so that it is found
-	// over SWWAF_REQUEST_MAX_BYTES only as it is read.
-	chunk := `{"netblock": "203.0.113.9", "duration": "1h"}`
-	s.adminRequest(adminClient, adminBearer+"\r\nTransfer-Encoding: chunked",
-		http.MethodPost, proxy.BansPath,
-		strconv.FormatInt(int64(len(chunk)), 16)+"\r\n"+chunk+"\r\n0\r\n\r\n",
-		http.StatusRequestEntityTooLarge, requestlog.ActionTooLarge)
-
-	if held := server.Ledger.Snapshot(); len(held) != 0 {
-		t.Errorf("the ledger holds %+v, want no ban", held)
-	}
-}
-
-func TestBanToAddSlowerThanTheClientRequestTimeoutIsRefused(t *testing.T) {
-	t.Parallel()
-
-	s, _, server := startWithClock(t, "", map[string]string{
-		adminToken:           adminSecret,
-		metricsToken:         token,
-		clientRequestTimeout: shortTimeoutSetting,
-	})
-
-	// The chunk announces 256 bytes and the rest of it never comes, so only
-	// the timeout ends the wait. A hold-up of the test process can only
-	// make the answer later, so the time is checked only for not being
-	// shorter than the timeout.
-	start := time.Now()
-
-	s.adminRequest(adminClient, adminBearer+"\r\nTransfer-Encoding: chunked",
-		http.MethodPost, proxy.BansPath, "100\r\n"+`{"netblock": "203.0.113.9", `,
-		http.StatusRequestTimeout, requestlog.ActionTimedOut)
-
-	if took := time.Since(start); took < shortTimeout {
-		t.Errorf("answered after %s, before the timeout of %s ran out", took, shortTimeout)
-	}
-
-	wantLimitHits(t, s.addr, clientRequestTimeout, 1)
-
-	if held := server.Ledger.Snapshot(); len(held) != 0 {
-		t.Errorf("the ledger holds %+v, want no ban", held)
-	}
-}
-
 func TestClientEndpointShowsTheClientAndItsBans(t *testing.T) {
 	t.Parallel()
 
 	s, clk, _ := startWithClock(t, "", map[string]string{
-		adminToken:          adminSecret,
-		rateLimitPerMinute:  "2",
-		rateLimitExemptNets: adminClient,
+		adminToken:         adminSecret,
+		rateLimitPerMinute: "2",
 	})
 	start := clk.Now()
 
@@ -339,7 +283,7 @@ func TestClientEndpointShowsTheClientAndItsBans(t *testing.T) {
 			Bans   []state.BanEntry  `json:"bans"`
 		}
 
-		decode(t, s.admin(http.MethodGet, proxy.ClientsPath+addr, "", http.StatusOK), &got)
+		decode(t, s.admin(http.MethodGet, servewaf.ClientsPath+addr, "", http.StatusOK), &got)
 
 		if got.Client == nil {
 			t.Fatalf("%s: no client", addr)
@@ -361,71 +305,16 @@ func TestClientEndpointShowsTheClientAndItsBans(t *testing.T) {
 
 	// Of an address no request came from and no ban covers, nothing is
 	// known.
-	got := s.admin(http.MethodGet, proxy.ClientsPath+"198.51.100.99", "", http.StatusOK)
+	got := s.admin(http.MethodGet, servewaf.ClientsPath+"198.51.100.99", "", http.StatusOK)
 	if string(got.body) != "{\n    \"client\": null,\n    \"bans\": []\n}\n" {
 		t.Errorf("an unknown client is answered\n%s", got.body)
 	}
 
-	s.admin(http.MethodGet, proxy.ClientsPath+"203.0.113", "", http.StatusBadRequest)
-	s.admin(http.MethodDelete, proxy.BansPath+"/203.0.113.0/24", "",
+	s.admin(http.MethodGet, servewaf.ClientsPath+"203.0.113", "", http.StatusBadRequest)
+	s.admin(http.MethodDelete, servewaf.BansPath+"/203.0.113.0/24", "",
 		http.StatusBadRequest)
 }
 
-func TestBannedClientIsRefusedAtTheEndpointsEvenWithTheToken(t *testing.T) {
-	t.Parallel()
-
-	s, _, _ := startWithClock(t, "", map[string]string{adminToken: adminSecret})
-
-	s.admin(http.MethodPost, proxy.BansPath, banOtherClient, http.StatusOK)
-
-	// otherClient cannot lift its own ban either.
-	for _, e := range adminEndpoints() {
-		s.adminRequest(otherClient, adminBearer, e.method, e.path, e.body,
-			http.StatusForbidden, requestlog.ActionBanned)
-	}
-}
-
-func TestAdminRequestsCountTowardTheLimits(t *testing.T) {
-	t.Parallel()
-
-	s, _, _ := startWithClock(t, "", map[string]string{
-		adminToken:         adminSecret,
-		rateLimitPerMinute: "2",
-	})
-
-	// A request refused for a missing token and one answered count toward
-	// the limit of two a minute, so the next breaks it.
-	s.adminRequest(client, "", http.MethodGet, proxy.BansPath, "",
-		http.StatusUnauthorized, requestlog.ActionAdmin)
-	s.adminRequest(client, adminBearer, http.MethodGet, proxy.BansPath, "",
-		http.StatusOK, requestlog.ActionAdmin)
-	s.adminRequest(client, adminBearer, http.MethodGet, proxy.BansPath, "",
-		http.StatusForbidden, requestlog.ActionRateLimited)
-}
-
-func TestClientInAllowNetsSkipsTheChecksButNeedsTheToken(t *testing.T) {
-	t.Parallel()
-
-	const allowed = "192.0.2.60" // in SWWAF_ALLOW_NETS
-
-	s, clk, server := startWithClock(t, "", map[string]string{
-		adminToken:         adminSecret,
-		allowNets:          allowed,
-		rateLimitPerMinute: "1",
-	})
-
-	// A ban on it refuses nothing, and its requests are not counted.
-	server.Ledger.BanForAdmin(netip.MustParsePrefix(allowed+"/32"), clk.Now(),
-		time.Time{}, "")
-
-	for range 2 {
-		s.adminRequest(allowed, "", http.MethodGet, proxy.BansPath, "",
-			http.StatusUnauthorized, requestlog.ActionAdmin)
-		s.adminRequest(allowed, adminBearer, http.MethodGet, proxy.BansPath, "",
-			http.StatusOK, requestlog.ActionAdmin)
-	}
-}
-
 func TestAdminEndpointsNeedTheTokenInObserveMode(t *testing.T) {
 	t.Parallel()
 
@@ -435,8 +324,7 @@ func TestAdminEndpointsNeedTheTokenInObserveMode(t *testing.T) {
 	})
 
 	for _, e := range adminEndpoints() {
-		s.adminRequest(adminClient, "", e.method, e.path, e.body,
-			http.StatusUnauthorized, requestlog.ActionAdmin)
+		s.adminRequest("", e.method, e.path, e.body, http.StatusUnauthorized)
 	}
 
 	if held := server.Ledger.Snapshot(); len(held) != 0 {
@@ -454,46 +342,40 @@ type adminEndpoint struct {
 // bans on otherClient, and asking about otherClient.
 func adminEndpoints() []adminEndpoint {
 	return []adminEndpoint{
-		{http.MethodGet, proxy.BansPath, ""},
-		{http.MethodPost, proxy.BansPath, banOtherClient},
-		{http.MethodDelete, proxy.BansPath + "/" + otherClient, ""},
-		{http.MethodGet, proxy.ClientsPath + otherClient, ""},
+		{http.MethodGet, servewaf.BansPath, ""},
+		{http.MethodPost, servewaf.BansPath, banOtherClient},
+		{http.MethodDelete, servewaf.BansPath + "/" + otherClient, ""},
+		{http.MethodGet, servewaf.ClientsPath + otherClient, ""},
 	}
 }
 
-// admin sends a request with method for path, with body, from
-// adminClient, with the admin token, and checks that it is answered with
-// status, its log line's action admin. It returns the answer.
+// admin sends a request with method for path, with body, to servewaf's own
+// address, with the admin token, and checks that it is answered with status, its
+// log line's action admin. It returns the answer.
 func (s *sender) admin(method, path, body string, status int) answer {
 	s.t.Helper()
 
-	return s.adminRequest(adminClient, adminBearer, method, path, body, status,
-		requestlog.ActionAdmin)
+	return s.adminRequest(adminBearer, method, path, body, status)
 }
 
-// adminRequest sends a request with method for path, with body, from the
-// client at from, with authorization as its Authorization header unless
-// it is "", and checks its answer's status and its log line's action, as
-// request does. authorization may end in more header lines. A body that
-// is not "" has its length announced, unless authorization names
-// Transfer-Encoding. It returns the answer.
+// adminRequest is admin with authorization as the request's Authorization header
+// unless it is "".
 func (s *sender) adminRequest(
-	from, authorization, method, path, body string, status int, action string,
+	authorization, method, path, body string, status int,
 ) answer {
 	s.t.Helper()
 
-	var header []string
-
+	req := newRequest(s.t, method, s.serveWAFAddr, path, strings.NewReader(body))
 	if authorization != "" {
-		header = append(header, "Authorization: "+authorization)
+		req.Header.Set("Authorization", authorization)
 	}
 
-	if body != "" && !strings.Contains(authorization, "Transfer-Encoding") {
-		header = append(header, "Content-Length: "+strconv.Itoa(len(body)))
-	}
+	got := do(s.t, req)
+	wantStatus(s.t, got, status)
 
-	_, got := s.requestWithBody(method, from, path, strings.Join(header, "\r\n"),
-		body, status, action)
+	line := s.out.endedLines(s.t, s.sent+1)[s.sent]
+	s.sent++
+	wantLine(s.t, line, status, requestlog.ActionAdmin)
 
 	return got
 }

internal/servewaf/alerts_test.go

@@ -1,4 +1,4 @@
-package proxy_test
+package servewaf_test
 
 import (
 	"maps"
@@ -10,8 +10,8 @@ import (
 
 	"sneak.berlin/go/smallwebwaf/internal/alerts"
 	"sneak.berlin/go/smallwebwaf/internal/bans"
-	"sneak.berlin/go/smallwebwaf/internal/proxy"
 	"sneak.berlin/go/smallwebwaf/internal/requestlog"
+	"sneak.berlin/go/smallwebwaf/internal/servewaf"
 )
 
 const (
@@ -201,7 +201,7 @@ func TestObserveModeWorksOutABanOnlyWhenItsAlertWouldBeSent(t *testing.T) {
 // never sent them, and returns the queue they wait in as well.
 func startWithAlerts(
 	t *testing.T, env map[string]string,
-) (*sender, *clock, *proxy.Server, *alerts.Queue) {
+) (*sender, *clock, *servewaf.Server, *alerts.Queue) {
 	t.Helper()
 
 	return startAppWithAlerts(t, func(http.ResponseWriter, *http.Request) {}, env)
@@ -210,7 +210,7 @@ func startWithAlerts(
 // startAppWithAlerts is startWithAlerts in front of the app handler.
 func startAppWithAlerts(
 	t *testing.T, handler http.HandlerFunc, env map[string]string,
-) (*sender, *clock, *proxy.Server, *alerts.Queue) {
+) (*sender, *clock, *servewaf.Server, *alerts.Queue) {
 	t.Helper()
 
 	app := startApp(t, handler)
@@ -224,7 +224,9 @@ func startAppWithAlerts(
 
 	addr, out, server, queue := startProxyWithAlerts(t, app.URL, "", clk.Now, settings)
 
-	return &sender{t: t, addr: addr, out: out}, clk, server, queue
+	s := &sender{t: t, addr: addr, serveWAFAddr: server.Addr, out: out}
+
+	return s, clk, server, queue
 }
 
 // banAlert returns the alert for event, raised by a request from client at
@@ -237,6 +239,7 @@ func banAlert(
 		Instance: alertInstance,
 		Time:     raised,
 		Event:    event,
+		Host:     appHost,
 		Client:   netip.MustParseAddr(client),
 		Netblock: ban.Netblock,
 		Reason:   ban.Reason,

internal/servewaf/anomaly_internal_test.go

@@ -1,4 +1,4 @@
-package proxy
+package servewaf
 
 import (
 	"net/netip"

internal/servewaf/anomaly_test.go

@@ -1,4 +1,4 @@
-package proxy_test
+package servewaf_test
 
 import (
 	"maps"
@@ -13,9 +13,9 @@ import (
 
 	"sneak.berlin/go/smallwebwaf/internal/alerts"
 	"sneak.berlin/go/smallwebwaf/internal/anomaly"
-	"sneak.berlin/go/smallwebwaf/internal/proxy"
 	"sneak.berlin/go/smallwebwaf/internal/ratelimit"
 	"sneak.berlin/go/smallwebwaf/internal/requestlog"
+	"sneak.berlin/go/smallwebwaf/internal/servewaf"
 )
 
 // The anomaly thresholds: the prefix of a scope followed by the end of a
@@ -117,6 +117,7 @@ func TestEachScopeAndWindowOverItsThresholdAlertsOncePerCooldown(t *testing.T) {
 					Instance: alertInstance,
 					Time:     start,
 					Event:    alerts.EventAnomaly,
+					Host:     appHost,
 					Client:   netip.MustParseAddr(client),
 					Netblock: scope.netblock,
 					ASN:      asnDE,
@@ -318,7 +319,7 @@ func TestRequestCountsForTheASNumberGeoJSGivesBeforeItEnds(t *testing.T) {
 	// kept.
 	geojsURL, _, release := startHeldGeoJS(t)
 
-	var server atomic.Pointer[proxy.Server]
+	var server atomic.Pointer[servewaf.Server]
 
 	app := startApp(t, func(http.ResponseWriter, *http.Request) {
 		release()

internal/servewaf/answertime_test.go

@@ -1,4 +1,4 @@
-package proxy_test
+package servewaf_test
 
 import (
 	"fmt"
@@ -16,10 +16,10 @@ import (
 
 	"sneak.berlin/go/smallwebwaf/internal/bans"
 	"sneak.berlin/go/smallwebwaf/internal/lookup"
-	"sneak.berlin/go/smallwebwaf/internal/proxy"
 	"sneak.berlin/go/smallwebwaf/internal/ratelimit"
 	"sneak.berlin/go/smallwebwaf/internal/reputation"
 	"sneak.berlin/go/smallwebwaf/internal/requestlog"
+	"sneak.berlin/go/smallwebwaf/internal/servewaf"
 )
 
 const (
@@ -81,7 +81,7 @@ func TestSixteenThousandCookiesAreRefusedWellWithinTheTimeLimit(t *testing.T) {
 		t.Errorf("answered after %s, want well within %s", took, answerTimeLimit)
 	}
 
-	wantDisposition(t, got, tooLarge, proxy.DispositionDeny)
+	wantDisposition(t, got, tooLarge, servewaf.DispositionDeny)
 
 	line := s.out.requestLine(t)
 	wantLine(t, line, tooLarge, requestlog.ActionTooLarge)
@@ -91,6 +91,18 @@ func TestSixteenThousandCookiesAreRefusedWellWithinTheTimeLimit(t *testing.T) {
 	}
 }
 
+func TestHeaderLimitRefusalNamesItsHeuristicCountsAndLimits(t *testing.T) {
+	t.Parallel()
+
+	s := startServeWAF(t, "", nil)
+	req := s.question(siteA, client, "/")
+	fillHeaders(req, headerFieldLimit+1)
+	do(t, req)
+
+	wantHeuristic(t, s.out.requestLine(t), "header_limits",
+		`{"fields": 101, "fields_limit": 100, "cookies": 0, "cookies_limit": 50}`)
+}
+
 func TestEachHeaderLimitRefusesARequestOverIt(t *testing.T) {
 	t.Parallel()
 
@@ -144,13 +156,13 @@ func TestEachHeaderLimitRefusesARequestOverIt(t *testing.T) {
 			line := s.out.requestLine(t)
 
 			if tc.refused {
-				wantDisposition(t, got, tooLarge, proxy.DispositionDeny)
+				wantDisposition(t, got, tooLarge, servewaf.DispositionDeny)
 				wantLine(t, line, tooLarge, requestlog.ActionTooLarge)
 
 				return
 			}
 
-			wantDisposition(t, got, http.StatusOK, proxy.DispositionAllow)
+			wantDisposition(t, got, http.StatusOK, servewaf.DispositionAllow)
 			wantLine(t, line, http.StatusOK, requestlog.ActionForward)
 
 			if line.DurationWAF == nil {
@@ -175,7 +187,7 @@ func TestHeaderLimitsHoldWhateverTheCoreRuleSetSettingsSay(t *testing.T) {
 			req := s.question(siteA, client, "/")
 			req.Header.Set(cookieHeader, cookies(cookieLimit+1))
 
-			wantDisposition(t, do(t, req), tooLarge, proxy.DispositionDeny)
+			wantDisposition(t, do(t, req), tooLarge, servewaf.DispositionDeny)
 		})
 	}
 }
@@ -187,7 +199,7 @@ func TestClientInTheAllowNetsSkipsTheHeaderLimits(t *testing.T) {
 	req := s.question(siteA, client, "/")
 	req.Header.Set(cookieHeader, cookies(cookieLimit+1))
 
-	wantDisposition(t, do(t, req), http.StatusOK, proxy.DispositionAllow)
+	wantDisposition(t, do(t, req), http.StatusOK, servewaf.DispositionAllow)
 }
 
 func TestObserveModeAllowsARequestOverTheHeaderLimitsUnread(t *testing.T) {
@@ -204,7 +216,7 @@ func TestObserveModeAllowsARequestOverTheHeaderLimitsUnread(t *testing.T) {
 		t.Errorf("answered after %s, want well within %s", took, answerTimeLimit)
 	}
 
-	wantDisposition(t, got, http.StatusOK, proxy.DispositionAllow)
+	wantDisposition(t, got, http.StatusOK, servewaf.DispositionAllow)
 
 	line := s.out.requestLine(t)
 	if line.WouldAction != requestlog.ActionTooLarge || line.DurationWAF != nil {
@@ -224,8 +236,8 @@ func TestRequestsOverTheHeaderLimitsCountTowardTheRateLimits(t *testing.T) {
 		return do(t, req)
 	}
 
-	wantDisposition(t, ask(), tooLarge, proxy.DispositionDeny)
-	wantDisposition(t, ask(), http.StatusForbidden, proxy.DispositionDeny)
+	wantDisposition(t, ask(), tooLarge, servewaf.DispositionDeny)
+	wantDisposition(t, ask(), http.StatusForbidden, servewaf.DispositionDeny)
 
 	lines := s.out.requestLines(t, 2)
 	wantLine(t, lines[1], http.StatusForbidden, requestlog.ActionRateLimited)
@@ -249,7 +261,7 @@ func TestTheHeaderLimitsComeAfterTheTrapPathsAndTheRuleFiles(t *testing.T) {
 			req := s.question(siteA, client, tc.path)
 			req.Header.Set(cookieHeader, cookies(cookieLimit+1))
 
-			wantDisposition(t, do(t, req), http.StatusForbidden, proxy.DispositionDeny)
+			wantDisposition(t, do(t, req), http.StatusForbidden, servewaf.DispositionDeny)
 			wantLine(t, s.out.requestLine(t), http.StatusForbidden, tc.action)
 		})
 	}
@@ -265,7 +277,7 @@ func TestNotWaitingForGeoJSNeverLowersAClientsLimit(t *testing.T) {
 	req := s.question(siteA, fromDE, "/")
 	req.Header.Set(cookieHeader, cookies(cookieLimit+1))
 
-	wantDisposition(t, do(t, req), tooLarge, proxy.DispositionDeny)
+	wantDisposition(t, do(t, req), tooLarge, servewaf.DispositionDeny)
 
 	line := s.out.requestLine(t)
 	wantLine(t, line, tooLarge, requestlog.ActionTooLarge)
@@ -275,7 +287,7 @@ func TestNotWaitingForGeoJSNeverLowersAClientsLimit(t *testing.T) {
 	}
 
 	// The client is under no ban, and GeoJS places it in a country.
-	wantDisposition(t, s.ask(fromDE, "/"), http.StatusOK, proxy.DispositionAllow)
+	wantDisposition(t, s.ask(fromDE, "/"), http.StatusOK, servewaf.DispositionAllow)
 }
 
 func TestAClientGeoJSPlacedInNoCountryCountsAsUnknownWithoutWaiting(t *testing.T) {
@@ -291,7 +303,7 @@ func TestAClientGeoJSPlacedInNoCountryCountsAsUnknownWithoutWaiting(t *testing.T
 	req := s.question(siteA, client, "/")
 	req.Header.Set(cookieHeader, cookies(cookieLimit+1))
 
-	wantDisposition(t, do(t, req), http.StatusForbidden, proxy.DispositionDeny)
+	wantDisposition(t, do(t, req), http.StatusForbidden, servewaf.DispositionDeny)
 	wantLine(t, s.out.requestLine(t), http.StatusForbidden, requestlog.ActionRateLimited)
 }
 
@@ -306,7 +318,7 @@ func TestObserveModeWaitsForGeoJSForARequestOverTheHeaderLimits(t *testing.T) {
 	req.Header.Set(cookieHeader, cookies(cookieLimit+1))
 
 	got := do(t, req)
-	wantDisposition(t, got, http.StatusOK, proxy.DispositionAllow)
+	wantDisposition(t, got, http.StatusOK, servewaf.DispositionAllow)
 
 	asn, country := got.header.Get("X-Client-Asn"), got.header.Get("X-Client-Country")
 	if asn != asnDE || country != "DE" {
@@ -315,31 +327,18 @@ func TestObserveModeWaitsForGeoJSForARequestOverTheHeaderLimits(t *testing.T) {
 	}
 }
 
-func TestWithoutACommandTheHeaderLimitsDoNotApply(t *testing.T) {
-	t.Parallel()
-
-	app := startApp(t, func(http.ResponseWriter, *http.Request) {})
-	addr, out := startProxy(t, app.URL, nil)
-
-	req := newRequest(t, http.MethodGet, addr, "/", http.NoBody)
-	req.Header.Set(cookieHeader, cookies(cookieLimit+1))
-	fillHeaders(req, headerFieldLimit+1)
-
-	wantStatus(t, do(t, req), http.StatusOK)
-	wantLine(t, out.requestLine(t), http.StatusOK, requestlog.ActionForward)
-}
-
 // newServeWAFInBubble makes a servewaf for a synctest bubble: GeoJS never
 // answers, a setting needs its answer, and everything is at its default but
 // for env. No request to it may use the network.
-func newServeWAFInBubble(t *testing.T, env map[string]string) (*proxy.Server, *output) {
+func newServeWAFInBubble(
+	t *testing.T, env map[string]string,
+) (*servewaf.Server, *output) {
 	t.Helper()
 
 	settings := map[string]string{deniedCountries: "KP"}
 	maps.Copy(settings, env)
 
-	server, out, _ := newServerWith(t, proxy.NewServeWAF, "http://app.invalid",
-		unansweredGeoJSURL, time.Now, settings)
+	server, out, _ := newServeWAF(t, unansweredGeoJSURL, time.Now, settings)
 
 	return server, out
 }
@@ -347,13 +346,13 @@ func newServeWAFInBubble(t *testing.T, env map[string]string) (*proxy.Server, *o
 // askDirectly hands a question about a request from client straight to server,
 // as change leaves it, and returns the answer's status and how long it took.
 func askDirectly(
-	t *testing.T, server *proxy.Server, change func(*http.Request),
+	t *testing.T, server *servewaf.Server, change func(*http.Request),
 ) (int, time.Duration) {
 	t.Helper()
 
 	req := httptest.NewRequestWithContext(t.Context(), http.MethodGet, "/", http.NoBody)
 	req.RemoteAddr = net.JoinHostPort(rproxyPeer, "1234")
-	req.Header.Set(proxy.ClientHeader, client)
+	req.Header.Set(servewaf.ClientHeader, client)
 	req.Header.Set(requestIDHeader, "the-id")
 	change(req)
 
@@ -366,17 +365,17 @@ func askDirectly(
 }
 
 // banClient bans client at now.
-func banClient(_ *testing.T, server *proxy.Server, now time.Time) {
+func banClient(_ *testing.T, server *servewaf.Server, now time.Time) {
 	server.Ledger.BanForLimit(netip.MustParsePrefix(client+"/32"), now, bans.Notes{})
 }
 
 // countClient counts one request from client at now for the rate limits.
-func countClient(_ *testing.T, server *proxy.Server, now time.Time) {
+func countClient(_ *testing.T, server *servewaf.Server, now time.Time) {
 	server.Limiter.Count(netip.MustParsePrefix(client+"/32"), now, wholeLimit)
 }
 
 // listClient puts client on the blocklist at dropURL.
-func listClient(t *testing.T, server *proxy.Server, now time.Time) {
+func listClient(t *testing.T, server *servewaf.Server, now time.Time) {
 	t.Helper()
 
 	err := server.Lists.Load([]reputation.List{{
@@ -388,13 +387,13 @@ func listClient(t *testing.T, server *proxy.Server, now time.Time) {
 }
 
 // decideOnClient puts client on the CrowdSec decision list.
-func decideOnClient(t *testing.T, server *proxy.Server, now time.Time) {
+func decideOnClient(t *testing.T, server *servewaf.Server, now time.Time) {
 	t.Helper()
 	loadDecisions(t, server, now, clientsDecision)
 }
 
 // leaveAsItIs prepares nothing.
-func leaveAsItIs(*testing.T, *proxy.Server, time.Time) {}
+func leaveAsItIs(*testing.T, *servewaf.Server, time.Time) {}
 
 func TestARefusedRequestDoesNotWaitForASlowGeoJS(t *testing.T) {
 	t.Parallel()
@@ -405,7 +404,7 @@ func TestARefusedRequestDoesNotWaitForASlowGeoJS(t *testing.T) {
 		name string
 		env  map[string]string
 		// prepare gets the server ready, at now, before the question.
-		prepare func(t *testing.T, server *proxy.Server, now time.Time)
+		prepare func(t *testing.T, server *servewaf.Server, now time.Time)
 		// cookie is the request's Cookie header.
 		cookie string
 		status int
@@ -476,7 +475,7 @@ func TestAQuestionWaitsForASlowGeoJSOnlyAsLongAsTheDefaultSays(t *testing.T) {
 		name string
 		env  map[string]string
 		// prepare gets the server ready, at now, before the question.
-		prepare func(t *testing.T, server *proxy.Server, now time.Time)
+		prepare func(t *testing.T, server *servewaf.Server, now time.Time)
 		status  int
 		action  string
 	}{
@@ -521,27 +520,6 @@ func TestAQuestionWaitsForASlowGeoJSOnlyAsLongAsTheDefaultSays(t *testing.T) {
 	}
 }
 
-func TestWithoutACommandARefusedRequestStillWaitsForGeoJS(t *testing.T) {
-	t.Parallel()
-
-	synctest.Test(t, func(t *testing.T) {
-		server, out, _ := newProxy(t, "http://app.invalid", unansweredGeoJSURL,
-			time.Now, map[string]string{deniedCountries: "KP", blocklistURLs: dropURL})
-		listClient(t, server, time.Now())
-
-		status, took := askDirectly(t, server, func(req *http.Request) {
-			req.RemoteAddr = net.JoinHostPort(client, "1234")
-		})
-
-		if status != http.StatusForbidden || took != defaultLookupWait {
-			t.Errorf("answered %d after %s, want %d after %s; output:\n%s",
-				status, took, http.StatusForbidden, defaultLookupWait, out.text())
-		}
-
-		wantLine(t, out.requestLine(t), http.StatusForbidden, requestlog.ActionDenied)
-	})
-}
-
 func TestServeWAFAnswersWithinTheTimeLimitWhileEveryOutsideSourceHangs(t *testing.T) {
 	t.Parallel()
 
@@ -555,11 +533,11 @@ func TestServeWAFAnswersWithinTheTimeLimitWhileEveryOutsideSourceHangs(t *testin
 
 	t.Cleanup(func() { _ = resolver.Close() })
 
-	server, out, _ := newServerWith(t, func(params proxy.Params) *proxy.Server {
+	server, out, _ := newServeWAFWith(t, func(params servewaf.Params) *servewaf.Server {
 		params.AbuseIPDBURL = silentAbuseIPDBURL
 
-		return proxy.NewServeWAF(params)
-	}, "http://app.invalid", held, time.Now, map[string]string{
+		return servewaf.New(params)
+	}, held, time.Now, map[string]string{
 		deniedCountries: "KP", wafMode: block,
 		dnsblZones: dnsblZone, dnsblResolver: resolver.LocalAddr().String(),
 		abuseIPDBKey:  accountKey,

internal/servewaf/bans.go

@@ -1,7 +1,10 @@
-package proxy
+package servewaf
+
+// The heuristic active_ban, and the code that makes bans, which several
+// heuristics share. active_ban reads SWWAF_MODE; the bans are the ban ledger's.
 
 import (
-	"net/http"
+	"context"
 	"net/netip"
 	"time"
 
@@ -18,11 +21,15 @@ func (rq *request) banResponse(action string) *refusal {
 	return &refusal{status: rq.h.config.BanResponse, action: action}
 }
 
-// banned reports whether a ban on a netblock the client is in covers the
-// request at now, and notes for the log line when that ban ends. A
-// request that makes the ban permanent, or in observe mode would have,
-// raises the alert for it.
-func (rq *request) banned(now time.Time) bool {
+// activeBan refuses a client a ban covers: a ban on a netblock the client is
+// in, in force at now. It notes for the log line when that ban ends. A request
+// that makes the ban permanent, or in observe mode would have, raises the alert
+// for it. Its figures are the ban's netblock and when it ends.
+type activeBan struct{}
+
+func (activeBan) name() string { return "active_ban" }
+
+func (activeBan) check(_ context.Context, rq *request, now time.Time) *verdict {
 	check := rq.h.ledger.Check
 	if rq.h.config.Observe {
 		check = rq.h.ledger.Find // the ban refuses nothing, and stays as it is
@@ -38,105 +45,31 @@ func (rq *request) banned(now time.Time) bool {
 		rq.alertBan(ban)
 	}
 
-	return banned
-}
-
-// limitBroken counts the request for the rate limits at now, notes the
-// client's counts for the log line, and reports whether the request takes
-// the client over a rate limit, as its limit percentage lowers it, which
-// breaks it.
-func (rq *request) limitBroken(now time.Time) bool {
-	counts, hit, over := rq.h.limiter.Count(rq.h.clientGroup(rq.client), now,
-		rq.limitPercent.percent)
-	rq.line.Counts = counts
-
-	if over {
-		rq.banForLimit(now, hit, rq.h.config.BanResponse)
+	if !banned {
+		return nil
 	}
 
-	return over
-}
-
-// countBytes counts the request's bytes, as countedBytes gives them, for
-// the byte limits, once its response has ended, and notes the client's
-// byte totals for the log line; its requests stay there as the rate limits
-// counted them. Only a request passed to the app has them counted, and
-// only one the rate limits counted; in observe mode, not one that enforce
-// mode would have refused. Bytes that take the client over a byte limit,
-// as its limit percentage for the byte limits lowers it, break it; the
-// response was passed on whole.
-func (rq *request) countBytes() {
-	if !rq.counted || rq.line.WouldAction != "" {
-		return
-	}
-
-	now := rq.h.now()
-
-	counts, hit, over := rq.h.limiter.CountBytes(rq.h.clientGroup(rq.client), now,
-		rq.countedBytes(), rq.bytesPercent.percent)
-	rq.line.Counts.MinuteBytes = counts.MinuteBytes
-	rq.line.Counts.HourBytes = counts.HourBytes
-	rq.line.Counts.DayBytes = counts.DayBytes
-
-	if over {
-		rq.banForLimit(now, hit, rq.out.status)
+	return &verdict{
+		action: requestlog.ActionBanned,
+		figures: map[string]any{
+			figureNetblock: ban.Netblock.String(), "ban_expires": rq.line.BanExpires,
+		},
 	}
 }
 
-// countRefusal counts the request for the error burst once it has been
-// answered, if smallwebwaf refused it after a rule file match, a trap path
-// or a Core Rule Set match, or for a missing or wrong token, and in
-// observe mode if enforce mode would have: more than
-// SWWAF_ERROR_BURST_THRESHOLD such refusals of the client within a minute
-// break a limit. A client in SWWAF_ALLOW_NETS, which the checks skip, is
-// not counted, and nothing is while the threshold is off.
-func (rq *request) countRefusal() {
-	cfg := rq.h.config
-	if cfg.ErrorBurstThreshold == 0 {
-		return
+// limitFigures are the figures of a heuristic that broke hit, a limit: its
+// window, the count and the limit.
+func limitFigures(hit ratelimit.Hit) map[string]any {
+	return map[string]any{
+		figureWindow: hit.Window, figureCount: hit.Count, figureLimit: hit.Limit,
 	}
-
-	// In observe mode, a request that enforce mode would have refused
-	// before it reached the endpoint has had no token refused there.
-	tokenRefused := rq.tokenRefused && rq.line.WouldAction == "" &&
-		!isInside(rq.client, cfg.AllowNets)
-	if !rq.attack && !rq.ruleBlocked && !rq.wafBlocked && !tokenRefused {
-		return
-	}
-
-	now := rq.h.now()
-
-	hit, over := rq.h.limiter.CountRefusal(rq.h.clientGroup(rq.client), now,
-		cfg.ErrorBurstThreshold)
-	if !over {
-		return
-	}
-
-	// What the client was sent, or in observe mode would have been.
-	status := rq.out.status
-
-	switch rq.line.WouldAction {
-	case requestlog.ActionRuleBlocked, requestlog.ActionWAFBlocked:
-		status = http.StatusForbidden
-	case requestlog.ActionBanned:
-		status = cfg.BanResponse
-	}
-
-	rq.banForLimit(now, hit, status)
 }
 
 // countedBytes returns the request's bytes, once it has ended, as the
 // byte limits and the anomaly thresholds count them: the response's body
-// bytes, the request's, or both, as SWWAF_BYTES_COUNT says. For an
-// upgraded connection, such as a WebSocket, which has closed by then, what
-// it carried from the app counts with the response's and what it carried
-// from the client with the request's.
+// bytes, the request's, or both, as SWWAF_BYTES_COUNT says.
 func (rq *request) countedBytes() int64 {
-	response, request := rq.out.bytes, rq.requestBytes()
-	if rq.upgraded != nil {
-		response += rq.upgraded.fromApp.Load()
-		request += rq.upgraded.toApp.Load()
-	}
+	response, request := rq.out.bytes, rq.requestBytes
 
 	switch rq.h.config.BytesCount {
 	case "response":
@@ -151,7 +84,7 @@ func (rq *request) countedBytes() int64 {
 // banForLimit bans the client's netblock at now for a broken limit, the
 // one hit names, notes the offence for the log line and counts the hit in
 // the metrics. status is what the client was sent, or is sent:
-// SWWAF_BAN_RESPONSE for a request over a rate limit, the app's answer for
+// SWWAF_BAN_RESPONSE for a request over a rate limit, what the report says for
 // one whose bytes broke a byte limit, the refusal for one that broke the
 // error burst. The ban's notes give the client's limit percentage for a
 // rate limit or a byte limit; the error burst is not lowered. The ban sets

internal/servewaf/bans_test.go

@@ -1,4 +1,4 @@
-package proxy_test
+package servewaf_test
 
 import (
 	"bufio"
@@ -9,13 +9,14 @@ import (
 	"net/netip"
 	"reflect"
 	"slices"
+	"strings"
 	"sync"
 	"testing"
 	"time"
 
 	"sneak.berlin/go/smallwebwaf/internal/bans"
-	"sneak.berlin/go/smallwebwaf/internal/proxy"
 	"sneak.berlin/go/smallwebwaf/internal/requestlog"
+	"sneak.berlin/go/smallwebwaf/internal/servewaf"
 )
 
 const (
@@ -227,6 +228,22 @@ func TestBannedClientIsRefusedBeforeItsCountryIsLookedUp(t *testing.T) {
 	}
 }
 
+func TestRefusalUnderABanNamesItsHeuristicNetblockAndEnd(t *testing.T) {
+	t.Parallel()
+
+	s, clk, _ := startWithClock(t, "", map[string]string{
+		rateLimitPerMinute: "1", banScopeV4Prefix: "24",
+	})
+	expires := requestlog.FormatTime(clk.Now().Add(time.Hour))
+
+	s.get(client, http.StatusOK, requestlog.ActionForward)
+	s.get(client, http.StatusForbidden, requestlog.ActionRateLimited)
+
+	line := s.get(otherClient, http.StatusForbidden, requestlog.ActionBanned)
+	wantHeuristic(t, line, "active_ban",
+		`{"netblock": "`+clientsNet+`", "ban_expires": "`+expires+`"}`)
+}
+
 func TestBanResponseAnswersEveryRefusalButTheSizeLimits(t *testing.T) {
 	t.Parallel()
 
@@ -374,14 +391,14 @@ func (c *clock) advance(d time.Duration) {
 	c.now = c.now.Add(d)
 }
 
-// startWithClock starts smallwebwaf in front of an app that answers 200,
+// startWithClock starts servewaf, and rproxy in front of an app that answers 200,
 // with the settings in env on top of trusting localhost's
 // X-Forwarded-For, clients' AS numbers and countries looked up at
 // geojsURL, and a clock set to midnight, the start of a bucket in every
 // window.
 func startWithClock(
 	t *testing.T, geojsURL string, env map[string]string,
-) (*sender, *clock, *proxy.Server) {
+) (*sender, *clock, *servewaf.Server) {
 	t.Helper()
 
 	app := startApp(t, func(http.ResponseWriter, *http.Request) {})
@@ -391,18 +408,19 @@ func startWithClock(
 
 	addr, out, server := startProxyWithClock(t, app.URL, geojsURL, clk.Now, settings)
 
-	return &sender{t: t, addr: addr, out: out}, clk, server
+	return &sender{t: t, addr: addr, serveWAFAddr: server.Addr, out: out}, clk, server
 }
 
-// sender sends requests to smallwebwaf one after another, each on a
-// connection of its own, and checks each one's answer and log line. They
-// must be the only requests smallwebwaf is sent, since the log lines are
-// matched to them in order.
+// sender sends requests to rproxy one after another, each on a connection of its
+// own, and checks each one's answer and log line. serveWAFAddr is where servewaf's
+// own endpoints are, which adminRequest asks. Every request servewaf gets must
+// come through the sender, since the log lines are matched to them in order.
 type sender struct {
-	t    *testing.T
-	addr string
-	out  *output
-	sent int
+	t            *testing.T
+	addr         string
+	serveWAFAddr string
+	out          *output
+	sent         int
 }
 
 // get sends a GET request for / from the client at from.
@@ -419,22 +437,19 @@ func (s *sender) get(from string, status int, action string) logLine {
 func (s *sender) request(from, path string, status int, action string) logLine {
 	s.t.Helper()
 
-	line, _ := s.requestWithHeader(from, path, "", status, action)
-
-	return line
+	return s.requestWithHeader(from, path, "", status, action)
 }
 
 // requestWithHeader is request with header, such as "Authorization:
-// Bearer x", added to the request unless it is "". It returns the body of
-// the answer too.
+// Bearer x", added to the request unless it is "".
 func (s *sender) requestWithHeader(
 	from, path, header string, status int, action string,
-) (logLine, string) {
+) logLine {
 	s.t.Helper()
 
-	line, got := s.requestWithBody(http.MethodGet, from, path, header, "", status, action)
+	line, _ := s.requestWithBody(http.MethodGet, from, path, header, "", status, action)
 
-	return line, string(got.body)
+	return line
 }
 
 // requestWithBody is requestWithHeader for a request with method, whose
@@ -450,10 +465,14 @@ func (s *sender) requestWithBody(
 		header += "\r\n"
 	}
 
+	// rproxy refuses a request with more than one.
+	if !strings.Contains(header, "User-Agent:") {
+		header += "User-Agent: " + userAgent + "\r\n"
+	}
+
 	conn := dial(s.t, s.addr)
-	send(s.t, conn, method+" "+path+" HTTP/1.1\r\nHost: "+appHost+
-		"\r\nUser-Agent: "+userAgent+"\r\n"+forwardedFor+": "+from+"\r\n"+
-		header+"\r\n"+body)
+	send(s.t, conn, method+" "+path+" HTTP/1.1\r\nHost: "+appHost+"\r\n"+
+		forwardedFor+": "+from+"\r\n"+header+"\r\n"+body)
 
 	err := conn.SetReadDeadline(time.Now().Add(waitLimit))
 	if err != nil {
@@ -478,7 +497,7 @@ func (s *sender) requestWithBody(
 			got.status, status)
 	}
 
-	line := s.out.requestLines(s.t, s.sent+1)[s.sent]
+	line := s.out.endedLines(s.t, s.sent+1)[s.sent]
 	s.sent++
 	wantLine(s.t, line, status, action)
 

internal/servewaf/biased.go

@@ -1,4 +1,4 @@
-package proxy
+package servewaf
 
 import (
 	"sneak.berlin/go/smallwebwaf/internal/config"

internal/servewaf/biased_test.go

@@ -1,10 +1,9 @@
-package proxy_test
+package servewaf_test
 
 import (
 	"fmt"
 	"io"
 	"maps"
-	"net"
 	"net/http"
 	"net/http/httptest"
 	"net/netip"
@@ -17,8 +16,8 @@ import (
 	"sneak.berlin/go/smallwebwaf/internal/alerts"
 	"sneak.berlin/go/smallwebwaf/internal/bans"
 	"sneak.berlin/go/smallwebwaf/internal/lookup/lookuptest"
-	"sneak.berlin/go/smallwebwaf/internal/proxy"
 	"sneak.berlin/go/smallwebwaf/internal/requestlog"
+	"sneak.berlin/go/smallwebwaf/internal/servewaf"
 )
 
 // The biased thresholds.
@@ -281,12 +280,12 @@ func TestClientWithoutAnAnswerInTimeHasTheUnknownLimitPercent(t *testing.T) {
 	// In a synctest bubble, as TestRequestWaitsAsLongAsTheLookupTimeoutSays
 	// says, with a GeoJS that never answers.
 	synctest.Test(t, func(t *testing.T) {
-		server, out, _ := newProxy(t, "http://app.invalid", unansweredGeoJSURL,
-			time.Now, map[string]string{unknownLimitPercent: "0"})
+		server, out, _ := newServeWAF(t, unansweredGeoJSURL, time.Now,
+			map[string]string{unknownLimitPercent: "0"})
 
 		// Once the time the request waits for its answer is up, the client
 		// counts as without a country, and its zero allowance refuses the
-		// request before it reaches the app.
+		// request.
 		serveFromDE(t, server, http.MethodGet, http.NoBody)
 
 		line := out.requestLine(t)
@@ -320,13 +319,8 @@ func TestRequestWaitsForItsLookupWhileABiasedThresholdIsSet(t *testing.T) {
 			// In a synctest bubble, as TestRequestWaitsAsLongAsTheLookupTimeoutSays
 			// says, with a GeoJS that never answers.
 			synctest.Test(t, func(t *testing.T) {
-				// The request's body is over SWWAF_REQUEST_MAX_BYTES, so that it
-				// is refused after the checks, and never reaches the app.
-				server, out, _ := newProxy(t, "http://app.invalid", unansweredGeoJSURL,
-					time.Now, map[string]string{
-						lookupTimeout: timeout.String(), requestMaxBytes: "1",
-						tc.setting: tc.value,
-					})
+				server, out, _ := newServeWAF(t, unansweredGeoJSURL, time.Now,
+					map[string]string{lookupTimeout: timeout.String(), tc.setting: tc.value})
 				began := time.Now()
 
 				serveFromDE(t, server, http.MethodPost, strings.NewReader("ab"))
@@ -340,8 +334,7 @@ func TestRequestWaitsForItsLookupWhileABiasedThresholdIsSet(t *testing.T) {
 					t.Errorf("the request waited %s for its answer, want %s", waited, want)
 				}
 
-				wantLine(t, out.requestLine(t), http.StatusRequestEntityTooLarge,
-					requestlog.ActionTooLarge)
+				wantLine(t, out.requestLine(t), http.StatusOK, requestlog.ActionForward)
 
 				// The bubble's clock stops once this function returns, so the
 				// request to GeoJS, which a request that did not wait leaves
@@ -426,7 +419,7 @@ func TestBanForALoweredLimitGivesThePercentageInItsNotesAndItsAlert(t *testing.T
 // clock.
 func startWithLookups(
 	t *testing.T, env map[string]string,
-) (*sender, *proxy.Server, *alerts.Queue) {
+) (*sender, *servewaf.Server, *alerts.Queue) {
 	t.Helper()
 
 	s, _, server, queue := startWithLookupsAndClock(t, env)
@@ -441,7 +434,7 @@ func startWithLookups(
 // country, and no other address.
 func startWithLookupsAndClock(
 	t *testing.T, env map[string]string,
-) (*sender, *clock, *proxy.Server, *alerts.Queue) {
+) (*sender, *clock, *servewaf.Server, *alerts.Queue) {
 	t.Helper()
 
 	path := filepath.Join(t.TempDir(), "ipinfo_lite.mmdb")
@@ -467,13 +460,15 @@ func (s *sender) uploadFrom(from string) logLine {
 	return line
 }
 
-// serveFromDE hands a request from fromDE with method and body straight to
-// server's handler, without the network, and returns once it is answered.
-func serveFromDE(t *testing.T, server *proxy.Server, method string, body io.Reader) {
+// serveFromDE hands a question about a request from fromDE with method and body
+// straight to server's handler, without the network, and returns once it is
+// answered.
+func serveFromDE(t *testing.T, server *servewaf.Server, method string, body io.Reader) {
 	t.Helper()
 
 	req := httptest.NewRequestWithContext(t.Context(), method, "/", body)
-	req.RemoteAddr = net.JoinHostPort(fromDE, "1234")
+	req.Header.Set(servewaf.ClientHeader, fromDE)
+	req.Header.Set(requestIDHeader, "the-id")
 
 	server.Handler.ServeHTTP(httptest.NewRecorder(), req)
 }

internal/servewaf/blocklists.go

@@ -0,0 +1,41 @@
+package servewaf
+
+// The heuristic blocklists. It reads SWWAF_BLOCKLIST_ACTION, and the blocklists
+// through the reputation lists.
+
+import (
+	"context"
+	"time"
+
+	"sneak.berlin/go/smallwebwaf/internal/requestlog"
+)
+
+// blocklists notes the blocklists that list the client, as noteListed does,
+// and refuses the request when SWWAF_BLOCKLIST_ACTION is deny. Being limit, it
+// lowers the client's limits instead (see limitPercentages), and being log, it
+// does nothing more. Its figure is the blocklists that list the client.
+type blocklists struct{}
+
+func (blocklists) name() string { return "blocklists" }
+
+func (blocklists) check(_ context.Context, rq *request, _ time.Time) *verdict {
+	listedBy := rq.h.lists.ListedBy(rq.client)
+	rq.blocklisted = len(listedBy) > 0
+	rq.noteListed(listedBy, "listed by a blocklist")
+
+	if !rq.refusedByBlocklists(listedBy) {
+		return nil
+	}
+
+	return &verdict{
+		action:  requestlog.ActionDenied,
+		figures: map[string]any{"lists": listedBy},
+	}
+}
+
+// refusedByBlocklists reports whether the heuristic blocklists refuses a
+// client, given listedBy, the blocklists that list it: it does when one lists
+// it and SWWAF_BLOCKLIST_ACTION is deny.
+func (rq *request) refusedByBlocklists(listedBy []string) bool {
+	return len(listedBy) > 0 && rq.h.config.BlocklistAction == deny
+}

internal/servewaf/bytelimits.go

@@ -0,0 +1,43 @@
+package servewaf
+
+// The heuristic byte_limits. It reads SWWAF_BYTES_COUNT, and the byte limits
+// and biased thresholds through the limiter and limitPercentages.
+
+import (
+	"context"
+	"time"
+
+	"sneak.berlin/go/smallwebwaf/internal/requestlog"
+)
+
+// byteLimits counts the request's bytes, as countedBytes gives them, for the
+// byte limits, once its report has come, and notes the client's byte totals for
+// the log line; its requests stay there as the rate limits counted them. Only
+// an allowed request has them counted, and only one the rate limits counted; in
+// observe mode, not one that enforce mode would have refused. Bytes that take
+// the client over a byte limit, as its limit percentage for the byte limits
+// lowers it, break it, which bans the client; the response was passed on whole.
+// Its figures are the window, the count and the limit.
+type byteLimits struct{}
+
+func (byteLimits) name() string { return "byte_limits" }
+
+func (byteLimits) check(_ context.Context, rq *request, now time.Time) *verdict {
+	if !rq.counted || rq.line.WouldAction != "" {
+		return nil
+	}
+
+	counts, hit, over := rq.h.limiter.CountBytes(rq.h.clientGroup(rq.client), now,
+		rq.countedBytes(), rq.bytesPercent.percent)
+	rq.line.Counts.MinuteBytes = counts.MinuteBytes
+	rq.line.Counts.HourBytes = counts.HourBytes
+	rq.line.Counts.DayBytes = counts.DayBytes
+
+	if !over {
+		return nil
+	}
+
+	rq.banForLimit(now, hit, rq.out.status)
+
+	return &verdict{action: requestlog.ActionBanned, figures: limitFigures(hit)}
+}

internal/servewaf/bytelimits_test.go

@@ -1,4 +1,4 @@
-package proxy_test
+package servewaf_test
 
 import (
 	"bufio"
@@ -47,8 +47,6 @@ const (
 func TestEachByteLimitBansOnceTheResponseHasEnded(t *testing.T) {
 	t.Parallel()
 
-	const scraper = "192.0.2.200"
-
 	for _, tc := range []struct {
 		setting, window string
 		// apart is the time between the two requests, which the window
@@ -94,12 +92,27 @@ func TestEachByteLimitBansOnceTheResponseHasEnded(t *testing.T) {
 
 			s.get(client, http.StatusForbidden, requestlog.ActionBanned)
 
-			wantMetric(t, s.scrape(scraper), `smallwebwaf_rate_limit_hits_total{`+
+			wantMetric(t, s.scrape(), `smallwebwaf_rate_limit_hits_total{`+
 				`instance="`+alertInstance+`",kind="bytes",window="`+tc.window+`"}`, 1)
 		})
 	}
 }
 
+func TestByteLimitBanNamesItsHeuristicWindowCountAndLimit(t *testing.T) {
+	t.Parallel()
+
+	s, _ := startWithAnswers(t, map[string]string{bytesLimitPerMinute: byteLimit})
+
+	line, _ := s.download()
+	wantAfterAnswerHeuristic(t, line, "", "null")
+
+	// Two answers of 70 bytes are over the limit of 99.
+	line, _ = s.download()
+	wantHeuristic(t, line, "", "null")
+	wantAfterAnswerHeuristic(t, line, "byte_limits",
+		`{"window": "minute", "count": 140, "limit": 99}`)
+}
+
 func TestResponseOverAByteLimitByItselfIsPassedOnWhole(t *testing.T) {
 	t.Parallel()
 
@@ -126,7 +139,7 @@ func TestBytesOfAnAnswerThatBreaksOffAreCounted(t *testing.T) {
 	// The 70 bytes passed on before the app broke off are over the limit of
 	// 50, and ban the client for an hour.
 	line, got := s.requestWithBody(http.MethodGet, client, "/", "", "", http.StatusOK,
-		requestlog.ActionUpstreamError)
+		requestlog.ActionForward)
 	if len(got.body) != answerBytes || line.LimitHit != minuteBytes ||
 		line.BanExpires != expires {
 		t.Errorf("got %d bytes, and the log line has limit_hit %q and ban_expires %q, "+
@@ -168,39 +181,6 @@ func TestWebSocketBytesAreCountedOnceItCloses(t *testing.T) {
 	}
 }
 
-func TestWebSocketPassesTheAnswerAfterTheClientStopsSending(t *testing.T) {
-	t.Parallel()
-
-	app := startApp(t, echoOnceTheClientStops)
-	addr, out := startProxy(t, app.URL,
-		map[string]string{trustedProxies: trustLocalhost})
-	s := &sender{t: t, addr: addr, out: out}
-
-	conn, reader := s.openWebSocket()
-	send(t, conn, uploadBody)
-
-	// The client closes its sending side and waits for the answer, which the
-	// app sends only once it has seen the client stop. smallwebwaf passes the
-	// close on to the app through CloseWrite on upgradedConn; without that,
-	// it closes both connections, and the answer is lost.
-	tcp, ok := conn.(*net.TCPConn)
-	if !ok {
-		t.Fatalf("connection is a %T, want a *net.TCPConn", conn)
-	}
-
-	err := tcp.CloseWrite()
-	if err != nil {
-		t.Fatalf("close the sending side: %v", err)
-	}
-
-	got, err := io.ReadAll(reader)
-	if err != nil || string(got) != uploadBody {
-		t.Errorf("got %q (%v), want %q", got, err, uploadBody)
-	}
-
-	s.closeWebSocket(conn)
-}
-
 func TestBytesCountSaysWhichBytesCount(t *testing.T) {
 	t.Parallel()
 
@@ -465,28 +445,6 @@ func answerAfterUpgrade(w http.ResponseWriter, _ *http.Request) {
 	}
 }
 
-// echoOnceTheClientStops is an app that switches protocols, as for a
-// WebSocket, reads what the client sends until the client stops sending,
-// and then sends it all back.
-func echoOnceTheClientStops(w http.ResponseWriter, _ *http.Request) {
-	conn, buffered, err := http.NewResponseController(w).Hijack()
-	if err != nil {
-		return
-	}
-
-	defer func() {
-		_ = conn.Close()
-	}()
-
-	_, _ = buffered.WriteString("HTTP/1.1 101 Switching Protocols\r\n" +
-		"Connection: Upgrade\r\nUpgrade: websocket\r\n\r\n")
-	_ = buffered.Flush()
-
-	received, _ := io.ReadAll(buffered)
-	_, _ = buffered.Write(received)
-	_ = buffered.Flush()
-}
-
 // webSocket opens a WebSocket from client to answerAfterUpgrade, sends a
 // line of bodyBytes on it, reads the answer, and closes it. It checks the
 // answer, and the log line as request does, and returns the log line.
@@ -543,7 +501,7 @@ func (s *sender) closeWebSocket(conn net.Conn) logLine {
 
 	_ = conn.Close()
 
-	line := s.out.requestLines(s.t, s.sent+1)[s.sent]
+	line := s.out.endedLines(s.t, s.sent+1)[s.sent]
 	s.sent++
 	wantLine(s.t, line, http.StatusSwitchingProtocols, requestlog.ActionForward)
 

internal/servewaf/client.go

@@ -0,0 +1,62 @@
+package servewaf
+
+import (
+	"crypto/rand"
+	"net/http"
+	"net/netip"
+	"slices"
+)
+
+// peerAddress is the address of the request's TCP peer.
+func peerAddress(r *http.Request) netip.Addr {
+	addrPort, err := netip.ParseAddrPort(r.RemoteAddr)
+	if err != nil {
+		return netip.Addr{}
+	}
+
+	return addrPort.Addr().Unmap()
+}
+
+// requestIDHeader carries the request's id, from rproxy.
+const requestIDHeader = "X-Request-ID"
+
+// requestID is the request's id: the one a question gives, or for any other
+// request a new random one.
+func requestID(r *http.Request, isQuestion bool) string {
+	if isQuestion {
+		return r.Header.Get(requestIDHeader)
+	}
+
+	return rand.Text()
+}
+
+// scheme is how the visitor reached rproxy, or the trusted proxy in front of
+// it, as a question says in X-Forwarded-Proto, or otherwise http.
+func scheme(r *http.Request, isQuestion bool) string {
+	proto := r.Header.Get("X-Forwarded-Proto")
+	if !isQuestion || proto == "" {
+		return "http"
+	}
+
+	return proto
+}
+
+// clientGroup is the client a request is counted toward: its IPv4
+// address, or its IPv6 group, the netblock its IPv6 address is in of the
+// length SWWAF_IPV6_GROUP_PREFIX sets, a /64 by default, since one abuser
+// usually holds a whole /64. An IPv4 address in IPv6 form counts as IPv4.
+func (h *handler) clientGroup(addr netip.Addr) netip.Prefix {
+	addr = addr.Unmap()
+	if addr.Is6() {
+		return netip.PrefixFrom(addr, h.config.IPv6GroupPrefix).Masked()
+	}
+
+	return netip.PrefixFrom(addr, addr.BitLen())
+}
+
+// isInside reports whether addr is in one of the netblocks.
+func isInside(addr netip.Addr, netblocks []netip.Prefix) bool {
+	return slices.ContainsFunc(netblocks, func(netblock netip.Prefix) bool {
+		return netblock.Contains(addr)
+	})
+}

internal/servewaf/coreruleset.go

@@ -1,9 +1,10 @@
-package proxy
+package servewaf
+
+// The heuristic core_rule_set. It reads SWWAF_WAF_MODE, SWWAF_WAF_EXEMPT_PATHS
+// and SWWAF_WAF_ANOMALY_THRESHOLD.
 
 import (
-	"errors"
-	"net/http"
-	"os"
+	"context"
 	"time"
 
 	"sneak.berlin/go/smallwebwaf/internal/alerts"
@@ -12,27 +13,29 @@ import (
 	"sneak.berlin/go/smallwebwaf/internal/waf"
 )
 
-// checkCoreRuleSet inspects the request with the Core Rule Set, unless
+// coreRuleSet inspects the request with the Core Rule Set, unless
 // SWWAF_WAF_MODE is off or SWWAF_WAF_EXEMPT_PATHS exempts its path, as
 // pathExempt decides, and notes the rules it matched and its score in the
 // log line, and the rules in the metrics. A score at or over
 // SWWAF_WAF_ANOMALY_THRESHOLD is a match: it raises the waf_block alert,
-// and in block mode refuses the request, which is an offence its client's
-// history counts, and so returns ActionWAFBlocked. It returns "" for a
-// request it does not refuse, and for one whose body meets a size or time
-// limit while the Core Rule Set reads it, which it notes nothing of.
-func (rq *request) checkCoreRuleSet() string {
+// and in block mode refuses the request with 403, which is an offence its
+// client's history counts. Its figures are the score and the threshold.
+type coreRuleSet struct{}
+
+func (coreRuleSet) name() string { return "core_rule_set" }
+
+func (coreRuleSet) check(_ context.Context, rq *request, _ time.Time) *verdict {
 	cfg := rq.h.config
 	if cfg.WAFMode == config.WAFModeOff || pathExempt(rq.in, cfg.WAFExemptPaths) {
-		return ""
+		return nil
 	}
 
 	start := time.Now()
 
-	result := rq.inspect()
-	if rq.refused.Load() != nil {
-		return "" // the refusal for that limit, which check returns
-	}
+	// A question's body has been read into memory, so that reading it here
+	// cannot fail.
+	result, read, _ := rq.h.coreRuleSet.Inspect(rq.in, rq.client, rq.in.Body)
+	rq.requestBytes = int64(len(read))
 
 	rq.line.DurationWAF = new(requestlog.Milliseconds(time.Since(start)))
 	rq.line.WAFRuleIDs = result.RuleIDs
@@ -44,51 +47,21 @@ func (rq *request) checkCoreRuleSet() string {
 
 	threshold := cfg.WAFAnomalyThreshold
 	if threshold == 0 || result.Score < threshold {
-		return ""
+		return nil
 	}
 
 	rq.alertWAFBlock(result)
 
 	if cfg.WAFMode == config.WAFModeDetect {
-		return ""
+		return nil
 	}
 
 	rq.wafBlocked = true
 
-	return requestlog.ActionWAFBlocked
-}
-
-// inspect runs the Core Rule Set on the request, which reads the part of
-// its body it inspects within SWWAF_CLIENT_REQUEST_TIMEOUT, and keeps that
-// part for the app. A client that runs out of time is refused with 408
-// here, and a body over SWWAF_REQUEST_MAX_BYTES with 413 as it is read;
-// check returns the refusal. A body that breaks off for any other reason
-// is passed on as far as it came, and the request to the app fails there,
-// as it would have without the Core Rule Set.
-func (rq *request) inspect() waf.Result {
-	if rq.body == nil {
-		// Nothing is read of no body, so nothing can go wrong reading it.
-		result, _, _ := rq.h.coreRuleSet.Inspect(rq.in, rq.client, http.NoBody)
-
-		return result
+	return &verdict{
+		action:  requestlog.ActionWAFBlocked,
+		figures: map[string]any{figureScore: result.Score, "threshold": threshold},
 	}
-
-	_ = rq.rc.SetReadDeadline(rq.clientRequestDeadline())
-	result, read, err := rq.h.coreRuleSet.Inspect(rq.in, rq.client, rq.body)
-	// The timeouts that run while the request goes to the app take over.
-	_ = rq.rc.SetReadDeadline(time.Time{})
-
-	rq.body.readByCoreRuleSet = read
-
-	if errors.Is(err, os.ErrDeadlineExceeded) {
-		rq.refuse(refusal{
-			status: http.StatusRequestTimeout,
-			action: requestlog.ActionTimedOut,
-			limit:  "SWWAF_CLIENT_REQUEST_TIMEOUT",
-		})
-	}
-
-	return result
 }
 
 // alertWAFBlock raises the waf_block alert for the request, which the Core

internal/servewaf/coreruleset_test.go

@@ -1,4 +1,4 @@
-package proxy_test
+package servewaf_test
 
 import (
 	"io"
@@ -8,7 +8,6 @@ import (
 	"strconv"
 	"strings"
 	"testing"
-	"time"
 
 	"sneak.berlin/go/smallwebwaf/internal/alerts"
 	"sneak.berlin/go/smallwebwaf/internal/ratelimit"
@@ -29,6 +28,13 @@ const (
 // formData is the type of a form's body.
 const formData = "application/x-www-form-urlencoded"
 
+// sizeLimit is SWWAF_WAF_BODY_LIMIT in the tests that read bodies, 1K as a
+// setting.
+const (
+	sizeLimit        = 1 << 10
+	sizeLimitSetting = "1K"
+)
+
 // sqlInjection asks for / with an SQL injection in its query, which only
 // the Core Rule Set's rule 942100 matches, with a score of 5, the default
 // SWWAF_WAF_ANOMALY_THRESHOLD.
@@ -96,7 +102,7 @@ func TestCoreRuleSetRefusesAttacksInBlockModeAndOnlyLogsThemInDetectMode(t *test
 			} {
 				s, _, _ := startWithClock(t, "", map[string]string{wafMode: tc.mode})
 
-				line, _ := s.requestWithHeader(client, attack.path, attack.header,
+				line := s.requestWithHeader(client, attack.path, attack.header,
 					tc.status, tc.action)
 				wantWAF(t, line, &attack.score, attack.ruleIDs...)
 			}
@@ -104,6 +110,16 @@ func TestCoreRuleSetRefusesAttacksInBlockModeAndOnlyLogsThemInDetectMode(t *test
 	}
 }
 
+func TestCoreRuleSetRefusalNamesItsHeuristicScoreAndThreshold(t *testing.T) {
+	t.Parallel()
+
+	s, _, _ := startWithClock(t, "", map[string]string{wafMode: block})
+
+	line := s.request(client, sqlInjection, http.StatusForbidden,
+		requestlog.ActionWAFBlocked)
+	wantHeuristic(t, line, "core_rule_set", `{"score": 5, "threshold": 5}`)
+}
+
 func TestOrdinaryRequestIsInspectedAndPassed(t *testing.T) {
 	t.Parallel()
 
@@ -299,7 +315,7 @@ func TestBodiesReachTheAppAsSentWhileBodiesAreRead(t *testing.T) {
 				tc.name, len(got.body), got.status, len(tc.body))
 		}
 
-		line := out.requestLines(t, i+1)[i]
+		line := out.endedLines(t, i+1)[i]
 		wantLine(t, line, http.StatusOK, requestlog.ActionForward)
 
 		if line.RequestBytes != int64(len(tc.body)) {
@@ -309,119 +325,6 @@ func TestBodiesReachTheAppAsSentWhileBodiesAreRead(t *testing.T) {
 	}
 }
 
-func TestFormBodyLongerThanTheLimitStreamsOnToTheApp(t *testing.T) {
-	t.Parallel()
-
-	const (
-		first = "a=" // and twice the limit of b's, then the rest
-		rest  = 64 * sizeLimit
-	)
-
-	// past is closed once the app has received twice what the Core Rule
-	// Set reads, and got is the length of the whole body it received.
-	past := make(chan struct{})
-	got := make(chan int64, 1)
-	app := startApp(t, func(_ http.ResponseWriter, r *http.Request) {
-		n, _ := io.CopyN(io.Discard, r.Body, 2*sizeLimit)
-
-		close(past)
-
-		m, _ := io.Copy(io.Discard, r.Body)
-		got <- n + m
-	})
-	addr, out := startProxy(t, app.URL, map[string]string{
-		wafMode: block, wafBodyLimit: sizeLimitSetting,
-	})
-
-	// The client sends the rest only once the app has received the first
-	// part: were smallwebwaf to hold the body until the end, it would
-	// never come.
-	body, sender := io.Pipe()
-
-	go func() {
-		_, _ = io.WriteString(sender, first+strings.Repeat("b", 2*sizeLimit))
-
-		select {
-		case <-past:
-		case <-time.After(waitLimit):
-			t.Error("the app got no more than the Core Rule Set reads " +
-				"before the whole body was sent")
-
-			_ = sender.CloseWithError(io.ErrUnexpectedEOF)
-
-			return
-		}
-
-		_, _ = io.WriteString(sender, strings.Repeat("b", rest))
-		_ = sender.Close()
-	}()
-
-	req := newRequest(t, http.MethodPost, addr, "/", body)
-	req.Header.Set("Content-Type", formData)
-	wantStatus(t, do(t, req), http.StatusOK)
-
-	want := int64(len(first) + 2*sizeLimit + rest)
-	if n := <-got; n != want {
-		t.Errorf("the app got %d bytes, want %d", n, want)
-	}
-
-	wantLine(t, out.requestLine(t), http.StatusOK, requestlog.ActionForward)
-}
-
-func TestClientTooSlowToSendWhatTheCoreRuleSetReads(t *testing.T) {
-	t.Parallel()
-
-	app := startApp(t, func(http.ResponseWriter, *http.Request) {})
-	addr, out := startProxy(t, app.URL, map[string]string{
-		wafMode: block, wafBodyLimit: sizeLimitSetting,
-		clientRequestTimeout: shortTimeoutSetting, metricsToken: token,
-	})
-
-	conn := dial(t, addr)
-	send(t, conn, "POST /comment HTTP/1.1\r\nHost: app\r\nContent-Type: "+formData+
-		"\r\nContent-Length: 100\r\n\r\ncontent=the first bytes")
-
-	wantStatus(t, readResponse(t, conn), http.StatusRequestTimeout)
-
-	line := out.requestLine(t)
-	wantLine(t, line, http.StatusRequestTimeout, requestlog.ActionTimedOut)
-	wantNotSentToTheApp(t, line)
-	wantLimitHits(t, addr, clientRequestTimeout, 1)
-}
-
-func TestBodyOverTheSizeLimitWhileTheCoreRuleSetReadsIt(t *testing.T) {
-	t.Parallel()
-
-	app := startApp(t, func(http.ResponseWriter, *http.Request) {})
-	addr, out := startProxy(t, app.URL, map[string]string{
-		wafMode: block, wafBodyLimit: "4K",
-		requestMaxBytes: sizeLimitSetting, metricsToken: token,
-	})
-
-	// Sent in chunks, its length is not announced, and is found to be over
-	// the limit as the Core Rule Set reads it.
-	body := io.MultiReader(strings.NewReader("a=" + strings.Repeat("b", 2*sizeLimit)))
-	req := newRequest(t, http.MethodPost, addr, "/", body)
-	req.Header.Set("Content-Type", formData)
-	wantStatus(t, do(t, req), http.StatusRequestEntityTooLarge)
-
-	line := out.requestLine(t)
-	wantLine(t, line, http.StatusRequestEntityTooLarge, requestlog.ActionTooLarge)
-	wantNotSentToTheApp(t, line)
-	wantLimitHits(t, addr, requestMaxBytes, 1)
-}
-
-// wantNotSentToTheApp checks that the request of line was not sent to the
-// app at all.
-func wantNotSentToTheApp(t *testing.T, line logLine) {
-	t.Helper()
-
-	_, sent := line.fields["duration_upstream_total"]
-	if sent {
-		t.Error("log line has duration_upstream_total, for a request sent to the app")
-	}
-}
-
 func TestResponsesAreNotInspected(t *testing.T) {
 	t.Parallel()
 
@@ -441,14 +344,12 @@ func TestResponsesAreNotInspected(t *testing.T) {
 		t.Errorf("answered %d with %q, want 200 with the app's page", got.status, got.body)
 	}
 
-	wantLine(t, out.requestLine(t), http.StatusOK, requestlog.ActionForward)
+	wantLine(t, out.endedLine(t), http.StatusOK, requestlog.ActionForward)
 }
 
 func TestCoreRuleSetRefusalIsAnOffenceAndCountsTowardTheErrorBurst(t *testing.T) {
 	t.Parallel()
 
-	const scraper = "192.0.2.200"
-
 	s, _, server := startWithClock(t, "", map[string]string{
 		wafMode: block, errorBurstThreshold: "2", metricsToken: token,
 	})
@@ -474,7 +375,7 @@ func TestCoreRuleSetRefusalIsAnOffenceAndCountsTowardTheErrorBurst(t *testing.T)
 		t.Errorf("history counts the offences %+v, want %+v", offences, want)
 	}
 
-	metrics := s.scrape(scraper)
+	metrics := s.scrape()
 	wantMetric(t, metrics,
 		`smallwebwaf_waf_matches_total{instance="app",mode="block",rule_id="942100"}`, 3)
 	wantMetric(t, metrics,
@@ -486,8 +387,6 @@ func TestCoreRuleSetRefusalIsAnOffenceAndCountsTowardTheErrorBurst(t *testing.T)
 func TestDetectModeMatchIsNoOffenceAndNotCountedTowardTheErrorBurst(t *testing.T) {
 	t.Parallel()
 
-	const scraper = "192.0.2.200"
-
 	s, _, server := startWithClock(t, "", map[string]string{
 		wafMode: detect, errorBurstThreshold: "2", metricsToken: token,
 	})
@@ -503,7 +402,7 @@ func TestDetectModeMatchIsNoOffenceAndNotCountedTowardTheErrorBurst(t *testing.T
 		t.Errorf("history counts the offences %+v, want none", offences)
 	}
 
-	metrics := s.scrape(scraper)
+	metrics := s.scrape()
 	wantMetric(t, metrics,
 		`smallwebwaf_waf_matches_total{instance="app",mode="detect",rule_id="942100"}`, 3)
 	wantNoSeries(t, metrics,
@@ -576,6 +475,7 @@ func TestCoreRuleSetMatchRaisesTheWAFBlockAlert(t *testing.T) {
 				Instance: alertInstance,
 				Time:     clk.Now(),
 				Event:    alerts.EventWAFBlock,
+				Host:     appHost,
 				Client:   netip.MustParseAddr(client),
 				Netblock: netip.MustParsePrefix(client + "/32"),
 				Reason:   "scored by the Core Rule Set at or over SWWAF_WAF_ANOMALY_THRESHOLD",

internal/servewaf/countries.go

@@ -0,0 +1,42 @@
+package servewaf
+
+// The heuristic countries. It reads SWWAF_DENIED_COUNTRIES and
+// SWWAF_EXCLUSIVELY_ALLOWED_COUNTRIES.
+
+import (
+	"context"
+	"slices"
+	"time"
+
+	"sneak.berlin/go/smallwebwaf/internal/requestlog"
+)
+
+// countries refuses a request by the client's country as it was looked up. A
+// client without a country, or whose country cannot be found, is refused only
+// by SWWAF_EXCLUSIVELY_ALLOWED_COUNTRIES. Its figures are the country and the
+// setting that refused it.
+type countries struct{}
+
+func (countries) name() string { return "countries" }
+
+func (countries) check(_ context.Context, rq *request, _ time.Time) *verdict {
+	denied := rq.h.config.DeniedCountries
+	allowed := rq.h.config.ExclusivelyAllowedCountries
+	country := rq.line.Country
+
+	var setting string
+
+	switch {
+	case slices.Contains(denied, country):
+		setting = "SWWAF_DENIED_COUNTRIES"
+	case len(allowed) > 0 && !slices.Contains(allowed, country):
+		setting = "SWWAF_EXCLUSIVELY_ALLOWED_COUNTRIES"
+	default:
+		return nil
+	}
+
+	return &verdict{
+		action:  requestlog.ActionCountryDenied,
+		figures: map[string]any{"country": country, "setting": setting},
+	}
+}

internal/servewaf/countries_test.go

@@ -1,4 +1,4 @@
-package proxy_test
+package servewaf_test
 
 import (
 	"encoding/json"
@@ -65,7 +65,7 @@ func TestCountryLists(t *testing.T) {
 				req.Header.Set(forwardedFor, sent.client)
 				got := do(t, req)
 
-				line := out.requestLines(t, i+1)[i]
+				line := out.endedLines(t, i+1)[i]
 				if line.ASN != sent.asn || line.ASName != sent.asName ||
 					line.Country != sent.country {
 					t.Errorf("log line has %q, %q and %q, want %q, %q and %q",
@@ -90,7 +90,24 @@ func TestCountryLists(t *testing.T) {
 	}
 }
 
-func TestCountryRefusalComesBeforeTheBody(t *testing.T) {
+func TestCountryRefusalNamesItsHeuristicCountryAndSetting(t *testing.T) {
+	t.Parallel()
+
+	geojsURL, _ := startGeoJS(t)
+	s, _, _ := startWithClock(t, geojsURL, map[string]string{
+		lookupTimeout: "1h", deniedCountries: "kp", allowedCountries: "de",
+	})
+
+	line := s.get(fromKP, http.StatusForbidden, requestlog.ActionCountryDenied)
+	wantHeuristic(t, line, "countries",
+		`{"country": "KP", "setting": "SWWAF_DENIED_COUNTRIES"}`)
+
+	line = s.get(unplaced, http.StatusForbidden, requestlog.ActionCountryDenied)
+	wantHeuristic(t, line, "countries",
+		`{"country": "", "setting": "SWWAF_EXCLUSIVELY_ALLOWED_COUNTRIES"}`)
+}
+
+func TestCountryRefusalKeepsARequestFromTheApp(t *testing.T) {
 	t.Parallel()
 
 	var calls atomic.Int32
@@ -109,13 +126,9 @@ func TestCountryRefusalComesBeforeTheBody(t *testing.T) {
 	req.Header.Set(forwardedFor, fromKP)
 	wantStatus(t, do(t, req), http.StatusForbidden)
 
-	line := out.requestLine(t)
+	line := out.endedLine(t)
 	wantLine(t, line, http.StatusForbidden, requestlog.ActionCountryDenied)
 
-	if line.RequestBytes != 0 {
-		t.Errorf("log line has request_bytes %d, want 0", line.RequestBytes)
-	}
-
 	if calls.Load() != 0 {
 		t.Errorf("the app was called %d times, want none", calls.Load())
 	}
@@ -211,7 +224,7 @@ func TestPrivateAddressIsNeverLookedUp(t *testing.T) {
 
 				wantStatus(t, do(t, req), http.StatusOK)
 
-				line := out.requestLines(t, i+1)[i]
+				line := out.endedLines(t, i+1)[i]
 				wantLine(t, line, http.StatusOK, requestlog.ActionForward)
 
 				for _, field := range []string{"asn", "as_name", "country"} {

internal/servewaf/crowdsec.go

@@ -0,0 +1,49 @@
+package servewaf
+
+// The heuristic crowdsec. It reads SWWAF_CROWDSEC_LAPI_URL, and the decisions
+// through the reputation lists.
+
+import (
+	"context"
+	"time"
+
+	"sneak.berlin/go/smallwebwaf/internal/bans"
+	"sneak.berlin/go/smallwebwaf/internal/reputation"
+	"sneak.berlin/go/smallwebwaf/internal/requestlog"
+)
+
+// crowdSec refuses a request when a decision of the CrowdSec decision list on
+// the client is in force at now. It then notes the list, as noteHit does, and
+// bans the client until that decision ends. Its figures are the decision's
+// scenario and when it ends.
+type crowdSec struct{}
+
+func (crowdSec) name() string { return "crowdsec" }
+
+func (crowdSec) check(_ context.Context, rq *request, now time.Time) *verdict {
+	decision, listed := rq.crowdSecDecisionInForce(now)
+	if !listed {
+		return nil
+	}
+
+	rq.noteHit(bans.ReputationHit{Source: rq.h.config.CrowdSecDecisionsURL},
+		"listed by the CrowdSec decision list")
+	rq.banForCrowdSec(now, decision)
+
+	return &verdict{
+		action: requestlog.ActionBanned,
+		figures: map[string]any{
+			"scenario": decision.Scenario,
+			"expires":  requestlog.FormatTime(decision.Expires),
+		},
+	}
+}
+
+// crowdSecDecisionInForce returns the decision of the CrowdSec decision list on
+// the client that is in force at now, and reports whether there is one, which
+// the heuristic crowdsec refuses the request for.
+func (rq *request) crowdSecDecisionInForce(
+	now time.Time,
+) (reputation.Decision, bool) {
+	return rq.h.lists.CrowdSecDecision(rq.client, now)
+}

internal/servewaf/crowdsec_test.go

@@ -1,4 +1,4 @@
-package proxy_test
+package servewaf_test
 
 import (
 	"net/http"
@@ -9,9 +9,9 @@ import (
 
 	"sneak.berlin/go/smallwebwaf/internal/alerts"
 	"sneak.berlin/go/smallwebwaf/internal/bans"
-	"sneak.berlin/go/smallwebwaf/internal/proxy"
 	"sneak.berlin/go/smallwebwaf/internal/reputation"
 	"sneak.berlin/go/smallwebwaf/internal/requestlog"
+	"sneak.berlin/go/smallwebwaf/internal/servewaf"
 )
 
 // The CrowdSec settings, and the tests' engine, which is never asked: each
@@ -84,7 +84,7 @@ func TestClientTheCrowdSecDecisionListListsIsBannedUntilTheDecisionEnds(t *testi
 
 	// The ban and the hit are counted, and the list has the metrics of any
 	// list fetched from a URL.
-	metrics := s.scrape(unplaced)
+	metrics := s.scrape()
 	labels := `{instance="` + alertInstance + `",source="` + decisionsURL + `"}`
 
 	wantMetric(t, metrics, `smallwebwaf_bans_made_total{cause="crowdsec",`+
@@ -95,6 +95,21 @@ func TestClientTheCrowdSecDecisionListListsIsBannedUntilTheDecisionEnds(t *testi
 		float64(fetched.Unix()))
 }
 
+func TestCrowdSecBanNamesItsHeuristicScenarioAndEnd(t *testing.T) {
+	t.Parallel()
+
+	s, clk, server, _ := startWithAlerts(t, map[string]string{
+		crowdSecURL: lapi, crowdSecKey: bouncerKey,
+	})
+	loadDecisions(t, server, clk.Now(), `[{"duration": "4h0m0s", `+
+		`"scenario": "crowdsecurity/ssh-bf", "scope": "Ip", "type": "ban", `+
+		`"value": "`+client+`"}]`)
+
+	line := s.get(client, http.StatusForbidden, requestlog.ActionBanned)
+	wantHeuristic(t, line, "crowdsec", `{"scenario": "crowdsecurity/ssh-bf", `+
+		`"expires": "`+requestlog.FormatTime(clk.Now().Add(4*time.Hour))+`"}`)
+}
+
 func TestEndedCrowdSecDecisionNoLongerBansThoughTheCopyStillHoldsIt(t *testing.T) {
 	t.Parallel()
 
@@ -168,7 +183,7 @@ func TestObserveModeForwardsAClientTheCrowdSecDecisionListListsAndAlertsTheBan(
 // decisionsURL, answer, the engine's answer, fetched at fetched, as
 // reputation.json would at start.
 func loadDecisions(
-	t *testing.T, server *proxy.Server, fetched time.Time, answer string,
+	t *testing.T, server *servewaf.Server, fetched time.Time, answer string,
 ) {
 	t.Helper()
 

internal/servewaf/denynets.go

@@ -0,0 +1,29 @@
+package servewaf
+
+// The heuristic deny_nets. It reads SWWAF_DENY_NETS.
+
+import (
+	"context"
+	"time"
+
+	"sneak.berlin/go/smallwebwaf/internal/requestlog"
+)
+
+// denyNets refuses a client in SWWAF_DENY_NETS. Its figure is the netblock of
+// the setting the client is in.
+type denyNets struct{}
+
+func (denyNets) name() string { return "deny_nets" }
+
+func (denyNets) check(_ context.Context, rq *request, _ time.Time) *verdict {
+	for _, netblock := range rq.h.config.DenyNets {
+		if netblock.Contains(rq.client) {
+			return &verdict{
+				action:  requestlog.ActionDenied,
+				figures: map[string]any{figureNetblock: netblock.String()},
+			}
+		}
+	}
+
+	return nil
+}

internal/servewaf/dnsbl.go

@@ -0,0 +1,36 @@
+package servewaf
+
+// The heuristic dnsbl. It reads SWWAF_REPUTATION_ACTION, and the DNSBL zones'
+// verdicts through the DNSBL checker.
+
+import (
+	"context"
+	"time"
+
+	"sneak.berlin/go/smallwebwaf/internal/requestlog"
+)
+
+// dnsbl notes the DNSBL zones whose verdict lists the client, as noteListed
+// does, and refuses the request when SWWAF_REPUTATION_ACTION is deny. Being
+// limit, it lowers the client's limits instead (see limitPercentages), and
+// being log, it does nothing more. A zone without a verdict on the client is
+// asked about it in the background, and the request does not wait for the
+// answer. Its figure is the zones that list the client, their keys masked.
+type dnsbl struct{}
+
+func (dnsbl) name() string { return "dnsbl" }
+
+func (dnsbl) check(ctx context.Context, rq *request, _ time.Time) *verdict {
+	listedBy := rq.h.dnsbl.ListedBy(ctx, rq.client)
+	rq.dnsblListed = len(listedBy) > 0
+	rq.noteListed(listedBy, "listed by a DNSBL zone")
+
+	if !rq.dnsblListed || rq.h.config.ReputationAction != deny {
+		return nil
+	}
+
+	return &verdict{
+		action:  requestlog.ActionDenied,
+		figures: map[string]any{"zones": listedBy},
+	}
+}

internal/servewaf/headerlimits.go

@@ -0,0 +1,71 @@
+package servewaf
+
+// The heuristic header_limits. It reads no setting: its limits are fixed.
+
+import (
+	"context"
+	"strings"
+	"time"
+
+	"sneak.berlin/go/smallwebwaf/internal/requestlog"
+)
+
+// The header limits: the most cookies and header fields a request may have
+// when the checks reach the Core Rule Set. Real clients never reach them.
+const (
+	maxCookies      = 50
+	maxHeaderFields = 100
+)
+
+// headerLimits refuses a request over the header limits, with 431. Its figures
+// are the request's header fields and cookies, and the limit of each.
+type headerLimits struct{}
+
+func (headerLimits) name() string { return "header_limits" }
+
+func (headerLimits) check(_ context.Context, rq *request, _ time.Time) *verdict {
+	fields, cookies := rq.headerCounts()
+	if !overHeaderLimits(fields, cookies) {
+		return nil
+	}
+
+	return &verdict{
+		action: requestlog.ActionTooLarge,
+		figures: map[string]any{
+			"fields": fields, "fields_limit": maxHeaderFields,
+			"cookies": cookies, "cookies_limit": maxCookies,
+		},
+	}
+}
+
+// overHeaderLimits reports whether a request with these counts of header fields
+// and cookies, as headerCounts counts them, is over the header limits: it has
+// more than maxHeaderFields fields or more than maxCookies cookies.
+func overHeaderLimits(fields, cookies int) bool {
+	return fields > maxHeaderFields || cookies > maxCookies
+}
+
+// headerCounts returns the request's header fields, each value of a header sent
+// twice being one, and its cookies, each part of a Cookie header between
+// semicolons being one unless it is empty or only spaces and tabs. The Core
+// Rule Set runs each of its rules on each cookie, so that thousands of small
+// cookies keep it busy for over a second. It trims only spaces and control
+// characters, of which a header value can hold only tabs, so a part of Unicode
+// spaces is a cookie to it.
+func (rq *request) headerCounts() (int, int) {
+	fields, cookies := 0, 0
+
+	for _, values := range rq.in.Header {
+		fields += len(values)
+	}
+
+	for _, value := range rq.in.Header.Values("Cookie") {
+		for part := range strings.SplitSeq(value, ";") {
+			if strings.Trim(part, " \t") != "" {
+				cookies++
+			}
+		}
+	}
+
+	return fields, cookies
+}

internal/servewaf/health_test.go

@@ -0,0 +1,40 @@
+package servewaf_test
+
+import (
+	"net/http"
+	"testing"
+
+	"sneak.berlin/go/smallwebwaf/internal/requestlog"
+	"sneak.berlin/go/smallwebwaf/internal/servewaf"
+)
+
+func TestHealthEndpointCountsTowardNoLimit(t *testing.T) {
+	t.Parallel()
+
+	// With a limit of one request a minute, any request counted before
+	// the last one would have it refused.
+	s, _, _ := startWithClock(t, "", map[string]string{rateLimitPerMinute: "1"})
+
+	const (
+		healthChecks = 3
+		contentType  = "text/plain; charset=utf-8"
+	)
+
+	for range healthChecks {
+		got := s.adminRequest("", http.MethodGet, servewaf.HealthPath, "", http.StatusOK)
+
+		if string(got.body) != "ok\n" || got.header.Get("Content-Type") != contentType {
+			t.Errorf("health endpoint answered %q with Content-Type %q, want ok "+
+				"with %q", got.body, got.header.Get("Content-Type"), contentType)
+		}
+	}
+
+	s.get(client, http.StatusOK, requestlog.ActionForward)
+
+	for _, line := range s.out.endedLines(t, healthChecks)[:healthChecks] {
+		if line.ResponseContentType != contentType {
+			t.Errorf("health check's log line has response_content_type %q, "+
+				"want %q", line.ResponseContentType, contentType)
+		}
+	}
+}

internal/servewaf/heuristics.go

@@ -0,0 +1,133 @@
+package servewaf
+
+import (
+	"context"
+	"time"
+)
+
+// To add a heuristic, write one file with a type that implements heuristic,
+// and add one line for it to one of the lists below. Its settings go in
+// config.Config, and the comment at the top of its file names them.
+
+// heuristic is one of the checks that decide what servewaf does with a request.
+type heuristic interface {
+	// name is the heuristic's name, which the log line gives.
+	name() string
+	// check looks at the request at now, and returns nil to let it through.
+	// ctx is the request's own context.
+	check(ctx context.Context, rq *request, now time.Time) *verdict
+}
+
+// verdict is a heuristic refusing a request, or banning its client: the action
+// the log line names, one of requestlog's Action constants, and the figures the
+// heuristic acted on, by name, such as the count and the limit.
+type verdict struct {
+	action  string
+	figures map[string]any
+}
+
+// The names of the figures that more than one heuristic gives.
+const (
+	figureWindow   = "window"
+	figureCount    = "count"
+	figureLimit    = "limit"
+	figureScore    = "score"
+	figureNetblock = "netblock"
+)
+
+// The lists of heuristics, each in the order its heuristics run. A client in
+// SWWAF_ALLOW_NETS skips them all.
+
+// beforeLookup are the heuristics that run before the client's AS number and
+// country are looked up, so that a client they refuse is not looked up.
+func beforeLookup() []heuristic {
+	return []heuristic{
+		denyNets{},
+		activeBan{},
+	}
+}
+
+// afterLookup are the heuristics that run once the lookup has been made.
+func afterLookup() []heuristic {
+	return []heuristic{
+		countries{},
+		blocklists{},
+		crowdSec{},
+		dnsbl{},
+		abuseIPDB{},
+		rateLimits{},
+		trapPaths{},
+		ruleFiles{},
+		headerLimits{},
+		coreRuleSet{},
+	}
+}
+
+// afterAnswer are the heuristics that run on a request once servewaf has
+// answered it, before its decision line is written. They ban the client, and do
+// not change what the request got: their verdict's action is not used.
+func afterAnswer() []heuristic {
+	return []heuristic{
+		refusalLimit{},
+	}
+}
+
+// onReport are the heuristics that run on an allowed request when rproxy's
+// report of it comes, before its report line is written. Like afterAnswer, they
+// only ban.
+func onReport() []heuristic {
+	return []heuristic{
+		byteLimits{},
+	}
+}
+
+// runAfterAnswer runs the heuristics of afterAnswer on the request, at the time
+// it is called.
+func (rq *request) runAfterAnswer(ctx context.Context) {
+	rq.runBanningHeuristics(ctx, afterAnswer())
+}
+
+// runHeuristics runs list, beforeLookup or afterLookup, on the request at now,
+// and returns the first verdict, or nil when none gives one. The log line's
+// heuristic and heuristic_figures name the heuristic that gave it, and give its
+// figures. ctx is the request's own context.
+func (rq *request) runHeuristics(
+	ctx context.Context, list []heuristic, now time.Time,
+) *verdict {
+	name, v := rq.firstVerdict(ctx, list, now)
+	if v != nil {
+		rq.line.Heuristic = name
+		rq.line.HeuristicFigures = v.figures
+	}
+
+	return v
+}
+
+// runBanningHeuristics runs list, afterAnswer or onReport, on the request at
+// the time it is called. The log line's after_answer_heuristic and
+// after_answer_heuristic_figures name the heuristic that gave a verdict, and
+// give its figures, so that heuristic and heuristic_figures still name the one
+// that refused the request. ctx is the request's own context.
+func (rq *request) runBanningHeuristics(ctx context.Context, list []heuristic) {
+	name, v := rq.firstVerdict(ctx, list, rq.h.now())
+	if v != nil {
+		rq.line.AfterAnswerHeuristic = name
+		rq.line.AfterAnswerHeuristicFigures = v.figures
+	}
+}
+
+// firstVerdict runs list on the request at now, in order, until a heuristic
+// gives a verdict, and returns that heuristic's name and its verdict, or "" and
+// nil when none gives one. ctx is the request's own context.
+func (rq *request) firstVerdict(
+	ctx context.Context, list []heuristic, now time.Time,
+) (string, *verdict) {
+	for _, each := range list {
+		v := each.check(ctx, rq, now)
+		if v != nil {
+			return each.name(), v
+		}
+	}
+
+	return "", nil
+}

internal/servewaf/history_test.go

@@ -1,4 +1,4 @@
-package proxy_test
+package servewaf_test
 
 import (
 	"io"
@@ -8,9 +8,9 @@ import (
 	"testing"
 	"time"
 
-	"sneak.berlin/go/smallwebwaf/internal/proxy"
 	"sneak.berlin/go/smallwebwaf/internal/ratelimit"
 	"sneak.berlin/go/smallwebwaf/internal/requestlog"
+	"sneak.berlin/go/smallwebwaf/internal/servewaf"
 )
 
 func TestHistoryKeepsEachRequestOfTheClient(t *testing.T) {
@@ -86,7 +86,7 @@ func TestHistoryCountsTheBodiesEachWay(t *testing.T) {
 
 	got := do(t, newRequest(t, http.MethodPost, addr, "/", strings.NewReader("abc")))
 	wantStatus(t, got, http.StatusOK)
-	out.requestLine(t)
+	out.endedLine(t)
 
 	history := historyOf(t, server, localhost)
 	if history.RequestBytes != 3 || history.ResponseBytes != 5 {
@@ -95,43 +95,38 @@ func TestHistoryCountsTheBodiesEachWay(t *testing.T) {
 	}
 }
 
-func TestHealthEndpointIsNotInTheHistory(t *testing.T) {
+func TestOwnEndpointsAreNotInTheHistory(t *testing.T) {
 	t.Parallel()
 
-	app := startApp(t, func(http.ResponseWriter, *http.Request) {})
-	addr, out, server := startProxyWithClock(t, app.URL, "", time.Now, nil)
+	s, _, server := startWithClock(t, "", map[string]string{metricsToken: token})
 
-	wantStatus(t, get(t, addr, proxy.HealthPath), http.StatusOK)
-	out.requestLine(t)
+	s.adminRequest("", http.MethodGet, servewaf.HealthPath, "", http.StatusOK)
+	s.adminRequest("", http.MethodGet, servewaf.MetricsPath, "", http.StatusUnauthorized)
+	s.scrape()
 
 	if clients := server.Limiter.Snapshot(); len(clients) != 0 {
 		t.Errorf("the table holds %+v, want no client", clients)
 	}
 }
 
-func TestRequestForSmallwebwafIsRefusedOnlyWithoutTheToken(t *testing.T) {
+func TestPathUnderTheOwnPrefixIsNeitherForwardedNorRefused(t *testing.T) {
 	t.Parallel()
 
 	app := startApp(t, func(http.ResponseWriter, *http.Request) {})
-	addr, out, server := startProxyWithClock(t, app.URL, "", time.Now,
-		map[string]string{metricsToken: token})
+	addr, out, server := startProxyWithClock(t, app.URL, "", time.Now, nil)
 
-	// The metrics and the 404 are neither forwarded nor refused; the 401
-	// is refused.
-	scrape(t, addr)
 	wantStatus(t, get(t, addr, "/_smallwebwaf/nothing"), http.StatusNotFound)
-	wantStatus(t, get(t, addr, proxy.MetricsPath), http.StatusUnauthorized)
-	out.requestLines(t, 3)
+	out.endedLine(t)
 
 	history := historyOf(t, server, localhost)
-	if history.Requests != 3 || history.Forwarded != 0 || history.Refused != 1 {
+	if history.Requests != 1 || history.Forwarded != 0 || history.Refused != 0 {
 		t.Errorf("history counts %d requests, %d forwarded and %d refused, "+
-			"want 3, 0 and 1", history.Requests, history.Forwarded, history.Refused)
+			"want 1, 0 and 0", history.Requests, history.Forwarded, history.Refused)
 	}
 }
 
 // historyOf returns the history of the client at addr.
-func historyOf(t *testing.T, server *proxy.Server, addr string) ratelimit.History {
+func historyOf(t *testing.T, server *servewaf.Server, addr string) ratelimit.History {
 	t.Helper()
 
 	client := netip.MustParsePrefix(addr + "/32")

internal/servewaf/lookup.go

@@ -1,4 +1,4 @@
-package proxy
+package servewaf
 
 import (
 	"context"
@@ -9,11 +9,10 @@ import (
 	"sneak.berlin/go/smallwebwaf/internal/lookup"
 )
 
-// The headers in which the app is passed the client's AS number and
-// country while SWWAF_ADD_LOOKUP_HEADERS is set. Go writes every header
-// name in this form, as it sends it and as it receives it, so X-Client-ASN
-// arrives as X-Client-Asn, and Del removes a client's own whatever their
-// case; header names are not case-sensitive.
+// The headers in which an answer of allow gives rproxy the client's AS number
+// and country, for the app, while SWWAF_ADD_LOOKUP_HEADERS is set. Go writes
+// every header name in this form, as it sends it and as it receives it, so
+// X-Client-ASN arrives as X-Client-Asn; header names are not case-sensitive.
 const (
 	asnHeader     = "X-Client-Asn"
 	countryHeader = "X-Client-Country"
@@ -37,7 +36,7 @@ func (rq *request) lookUp(ctx context.Context, now time.Time) {
 	switch {
 	case rq.h.config.LookupSource == "file":
 		rq.lookupAnswer = rq.h.lookupFile.LookUp(client)
-	case rq.h.answersQuestions() && rq.refusedWhateverTheAnswer(now):
+	case rq.refusedWhateverTheAnswer(now):
 		rq.lookupAnswer = rq.h.geojs.LookUpWithoutWaiting(ctx, client)
 		rq.skippedLookupWait = rq.lookupAnswer.Answered.IsZero()
 	default:
@@ -60,8 +59,8 @@ func (h *handler) addLookup(answer lookup.Answer) {
 		answer.ASN, answer.ASName, answer.Country)
 }
 
-// setLookupHeaders sets the headers in which the app is passed the
-// client's AS number and country, leaving out one that is unknown.
+// setLookupHeaders sets the headers that give the client's AS number and
+// country, leaving out one that is unknown.
 func setLookupHeaders(header http.Header, asn, country string) {
 	if asn != "" {
 		header.Set(asnHeader, asn)

internal/servewaf/lookup_test.go

@@ -1,9 +1,7 @@
-package proxy_test
+package servewaf_test
 
 import (
-	"net"
 	"net/http"
-	"net/http/httptest"
 	"net/netip"
 	"path/filepath"
 	"slices"
@@ -142,7 +140,7 @@ func TestRequestThatWaitedForItsLookupIsCountedWhenItGoesOn(t *testing.T) {
 		t.Fatalf("first request: %v", err)
 	}
 
-	wantLine(t, out.requestLines(t, 2)[1], http.StatusOK, requestlog.ActionForward)
+	wantLine(t, out.endedLines(t, 2)[1], http.StatusOK, requestlog.ActionForward)
 
 	// The third request's count holds all three: the first was counted
 	// when it went on, in the minute under way, and the second's count
@@ -150,7 +148,7 @@ func TestRequestThatWaitedForItsLookupIsCountedWhenItGoesOn(t *testing.T) {
 	clk.advance(500 * time.Millisecond)
 	wantStatus(t, do(t, requestFromDE()), http.StatusOK)
 
-	if got := out.requestLines(t, 3)[2].Counts.Minute; got != 3 {
+	if got := out.endedLines(t, 3)[2].Counts.Minute; got != 3 {
 		t.Errorf("the third request's count in the minute is %v, want 3", got)
 	}
 }
@@ -381,24 +379,21 @@ func TestRequestWaitsAsLongAsTheLookupTimeoutSays(t *testing.T) {
 	// clock of the test's own: the wait lasts exactly as long as it should,
 	// however slowly the test process runs. Nothing in it may wait on the
 	// network, which would keep that clock from moving on: the request is
-	// handed to the proxy's handler, and GeoJS is one that never answers.
+	// handed to servewaf's handler, and GeoJS is one that never answers.
 	synctest.Test(t, func(t *testing.T) {
 		// Not the default. The exclusive list needs the answer, and the app
 		// is never reached.
 		const timeout = 3 * time.Second
 
-		server, out, _ := newProxy(t, "http://app.invalid", unansweredGeoJSURL,
-			time.Now, map[string]string{
+		server, out, _ := newServeWAF(t, unansweredGeoJSURL, time.Now,
+			map[string]string{
 				lookupTimeout:    timeout.String(),
 				allowedCountries: "DE",
 			})
 
-		req := httptest.NewRequestWithContext(t.Context(), http.MethodGet, "/",
-			http.NoBody)
-		req.RemoteAddr = net.JoinHostPort(fromDE, "1234")
 		began := time.Now()
 
-		server.Handler.ServeHTTP(httptest.NewRecorder(), req)
+		serveFromDE(t, server, http.MethodGet, http.NoBody)
 
 		if waited := time.Since(began); waited != timeout {
 			t.Errorf("the request waited %s for its answer, want %s", waited, timeout)

internal/servewaf/metrics_test.go

@@ -1,4 +1,4 @@
-package proxy_test
+package servewaf_test
 
 import (
 	"io"
@@ -7,15 +7,13 @@ import (
 	"net/netip"
 	"strconv"
 	"strings"
-	"sync"
-	"sync/atomic"
 	"testing"
 	"time"
 
 	"sneak.berlin/go/smallwebwaf/internal/bans"
 	"sneak.berlin/go/smallwebwaf/internal/lookup"
-	"sneak.berlin/go/smallwebwaf/internal/proxy"
 	"sneak.berlin/go/smallwebwaf/internal/requestlog"
+	"sneak.berlin/go/smallwebwaf/internal/servewaf"
 )
 
 const (
@@ -30,65 +28,38 @@ const (
 func TestMetricsAreOffWhileTheTokenIsUnset(t *testing.T) {
 	t.Parallel()
 
-	var calls atomic.Int32
-
-	app := startApp(t, func(http.ResponseWriter, *http.Request) {
-		calls.Add(1)
-	})
-	addr, out := startProxy(t, app.URL, nil)
+	s, _, _ := startWithClock(t, "", nil)
 
 	// An empty token does not match the unset one either.
-	for i, authorization := range []string{bearer, "Bearer ", ""} {
-		req := newRequest(t, http.MethodGet, addr, proxy.MetricsPath, http.NoBody)
-		if authorization != "" {
-			req.Header.Set("Authorization", authorization)
-		}
-
-		wantStatus(t, do(t, req), http.StatusNotFound)
-		wantLine(t, out.requestLines(t, i+1)[i], http.StatusNotFound,
-			requestlog.ActionAdmin)
-	}
-
-	if calls.Load() != 0 {
-		t.Errorf("the app was called %d times, want never", calls.Load())
+	for _, authorization := range []string{bearer, "Bearer ", ""} {
+		s.adminRequest(authorization, http.MethodGet, servewaf.MetricsPath, "",
+			http.StatusNotFound)
 	}
 }
 
 func TestMetricsNeedTheTokenAndOtherPathsAreNotFound(t *testing.T) {
 	t.Parallel()
 
-	var calls atomic.Int32
+	s, _, _ := startWithClock(t, "", map[string]string{metricsToken: token})
 
-	app := startApp(t, func(http.ResponseWriter, *http.Request) {
-		calls.Add(1)
-	})
-	addr, out := startProxy(t, app.URL, map[string]string{metricsToken: token})
-
-	for i, tc := range []struct {
+	for _, tc := range []struct {
 		method, path, authorization string
 		status                      int
 	}{
-		{http.MethodGet, proxy.MetricsPath, "", http.StatusUnauthorized},
+		{http.MethodGet, servewaf.MetricsPath, "", http.StatusUnauthorized},
 		{
-			http.MethodGet, proxy.MetricsPath, "Bearer " + strings.ToUpper(token),
+			http.MethodGet, servewaf.MetricsPath, "Bearer " + strings.ToUpper(token),
 			http.StatusUnauthorized,
 		},
-		{http.MethodGet, proxy.MetricsPath, "Basic " + token, http.StatusUnauthorized},
-		{http.MethodGet, proxy.MetricsPath, bearer, http.StatusOK},
-		{http.MethodGet, proxy.MetricsPath, "bearer " + token, http.StatusOK},
-		{http.MethodPost, proxy.MetricsPath, bearer, http.StatusNotFound},
-		{http.MethodGet, proxy.MetricsPath + "/", bearer, http.StatusNotFound},
+		{http.MethodGet, servewaf.MetricsPath, "Basic " + token, http.StatusUnauthorized},
+		{http.MethodGet, servewaf.MetricsPath, bearer, http.StatusOK},
+		{http.MethodGet, servewaf.MetricsPath, "bearer " + token, http.StatusOK},
+		{http.MethodPost, servewaf.MetricsPath, bearer, http.StatusNotFound},
+		{http.MethodGet, servewaf.MetricsPath + "/", bearer, http.StatusNotFound},
 		{http.MethodGet, "/_smallwebwaf/bans", bearer, http.StatusNotFound},
-		{http.MethodPost, proxy.HealthPath, "", http.StatusNotFound},
+		{http.MethodPost, servewaf.HealthPath, "", http.StatusNotFound},
 	} {
-		req := newRequest(t, tc.method, addr, tc.path, http.NoBody)
-		if tc.authorization != "" {
-			req.Header.Set("Authorization", tc.authorization)
-		}
-
-		got := do(t, req)
-		wantStatus(t, got, tc.status)
-		wantLine(t, out.requestLines(t, i+1)[i], tc.status, requestlog.ActionAdmin)
+		got := s.adminRequest(tc.authorization, tc.method, tc.path, "", tc.status)
 
 		if tc.status == http.StatusUnauthorized &&
 			got.header.Get("WWW-Authenticate") != "Bearer" {
@@ -101,58 +72,28 @@ func TestMetricsNeedTheTokenAndOtherPathsAreNotFound(t *testing.T) {
 			t.Errorf("the metrics are\n%s", got.body)
 		}
 	}
-
-	if calls.Load() != 0 {
-		t.Errorf("the app was called %d times, want never", calls.Load())
-	}
-}
-
-func TestMetricsAreAskedForThroughTheChecks(t *testing.T) {
-	t.Parallel()
-
-	s, _, _ := startWithClock(t, "", map[string]string{
-		metricsToken:       token,
-		rateLimitPerMinute: "1",
-	})
-
-	// Asking for the metrics counts toward the client's limit of one
-	// request a minute, so its next request breaks it, and bans it. A
-	// banned client is refused the metrics too.
-	s.scrape(client)
-	s.get(client, http.StatusForbidden, requestlog.ActionRateLimited)
-	s.requestWithHeader(client, proxy.MetricsPath, "Authorization: "+bearer,
-		http.StatusForbidden, requestlog.ActionBanned)
 }
 
 func TestMetricsCountTheTraffic(t *testing.T) {
 	t.Parallel()
 
-	arrived, release := make(chan struct{}), make(chan struct{})
 	app := startApp(t, func(w http.ResponseWriter, r *http.Request) {
 		_, _ = io.Copy(io.Discard, r.Body)
-
-		if r.URL.Path == "/held" {
-			close(arrived)
-			<-release
-		}
-
 		_, _ = io.WriteString(w, "hello")
 	})
-	releaseApp := sync.OnceFunc(func() { close(release) })
-	t.Cleanup(releaseApp)
-
-	addr, out := startProxy(t, app.URL, map[string]string{metricsToken: token})
+	addr, out, server := startProxyWithClock(t, app.URL, "", time.Now,
+		map[string]string{metricsToken: token})
 
 	got := do(t, newRequest(t, http.MethodPost, addr, "/", strings.NewReader("abc")))
 	wantStatus(t, got, http.StatusOK)
 	wantStatus(t, get(t, addr, "/_smallwebwaf/nothing"), http.StatusNotFound)
-	out.requestLines(t, 2)
+	out.endedLines(t, 2)
 
 	forward := `{action="forward",instance="app",status_class="2xx"}`
 	notFound := `{action="admin",instance="app",status_class="4xx"}`
 
 	// The request for the metrics is itself under way.
-	metrics := scrape(t, addr)
+	metrics := scrape(t, server.Addr)
 	wantMetric(t, metrics, "smallwebwaf_requests_total"+forward, 1)
 	wantMetric(t, metrics, "smallwebwaf_requests_total"+notFound, 1)
 	wantMetric(t, metrics, "smallwebwaf_request_bytes_total"+forward, 3)
@@ -166,50 +107,20 @@ func TestMetricsCountTheTraffic(t *testing.T) {
 	wantMetric(t, metrics, `smallwebwaf_requests_in_flight{instance="app"}`, 1)
 	metric(t, metrics, `go_goroutines{instance="app"}`)
 	metric(t, metrics, `process_start_time_seconds{instance="app"}`)
-
-	// A request the app holds is under way until it ends.
-	httpClient := newClient(t)
-	held := newRequest(t, http.MethodGet, addr, "/held", http.NoBody)
-	ended := make(chan error, 1)
-
-	go func() {
-		res, err := httpClient.Do(held)
-		if err == nil {
-			err = readAnswer(res).err
-		}
-
-		ended <- err
-	}()
-
-	<-arrived
-	wantMetric(t, scrape(t, addr), `smallwebwaf_requests_in_flight{instance="app"}`, 2)
-	releaseApp()
-
-	err := <-ended
-	if err != nil {
-		t.Fatalf("held request: %v", err)
-	}
-
-	out.requestLines(t, 5)
-	wantMetric(t, scrape(t, addr), `smallwebwaf_requests_in_flight{instance="app"}`, 1)
 }
 
 func TestMetricsCountLimitsAndBans(t *testing.T) {
 	t.Parallel()
 
-	const (
-		scraper = "192.0.2.200" // in SWWAF_RATE_LIMIT_EXEMPT_NETS
-		denied  = "192.0.2.50"  // in SWWAF_DENY_NETS
-	)
+	const denied = "192.0.2.50" // in SWWAF_DENY_NETS
 
 	s, clk, _ := startWithClock(t, "", map[string]string{
-		metricsToken:        token,
-		rateLimitPerMinute:  "1",
-		rateLimitExemptNets: scraper,
-		denyNets:            denied,
-		banResponse:         banResponseClose,
-		limitBanDuration:    "1h",
-		maxBanDuration:      "2h",
+		metricsToken:       token,
+		rateLimitPerMinute: "1",
+		denyNets:           denied,
+		banResponse:        banResponseClose,
+		limitBanDuration:   "1h",
+		maxBanDuration:     "2h",
 	})
 
 	// SWWAF_BAN_RESPONSE=close sends no status at all.
@@ -219,7 +130,7 @@ func TestMetricsCountLimitsAndBans(t *testing.T) {
 	s.get(client, http.StatusOK, requestlog.ActionForward)
 	s.get(client, 0, requestlog.ActionRateLimited)
 
-	metrics := s.scrape(scraper)
+	metrics := s.scrape()
 	wantMetric(t, metrics,
 		`smallwebwaf_requests_total{action="denied",instance="app",status_class="none"}`, 1)
 	wantMetric(t, metrics, `smallwebwaf_rate_limit_hits_total{instance="app",`+
@@ -230,38 +141,35 @@ func TestMetricsCountLimitsAndBans(t *testing.T) {
 	wantMetric(t, metrics, `smallwebwaf_permanent_bans{instance="app"}`, 0)
 
 	clk.advance(time.Hour)
-	wantMetric(t, s.scrape(scraper), `smallwebwaf_active_bans{instance="app"}`, 0)
+	wantMetric(t, s.scrape(), `smallwebwaf_active_bans{instance="app"}`, 0)
 
 	// A limit broken again right after would ban for three hours, longer
 	// than SWWAF_MAX_BAN_DURATION, so the ban is permanent.
 	s.get(client, http.StatusOK, requestlog.ActionForward)
 	s.get(client, 0, requestlog.ActionRateLimited)
 
-	metrics = s.scrape(scraper)
+	metrics = s.scrape()
 	wantMetric(t, metrics, `smallwebwaf_rate_limit_hits_total{instance="app",`+
 		`kind="requests",window="minute"}`, 2)
 	wantMetric(t, metrics, `smallwebwaf_offences_total{instance="app",kind="limit"}`, 2)
 	wantMetric(t, metrics, `smallwebwaf_bans_made_total{cause="limit",instance="app"}`, 2)
 	wantMetric(t, metrics, `smallwebwaf_active_bans{instance="app"}`, 1)
 	wantMetric(t, metrics, `smallwebwaf_permanent_bans{instance="app"}`, 1)
-	// denied, client, and the scraper as of its earlier requests.
-	wantMetric(t, metrics, `smallwebwaf_tracked_clients{instance="app"}`, 3)
+	// denied and client.
+	wantMetric(t, metrics, `smallwebwaf_tracked_clients{instance="app"}`, 2)
 }
 
 func TestMetricsCountTheBansAnAdminMakes(t *testing.T) {
 	t.Parallel()
 
-	const scraper = "192.0.2.200" // in SWWAF_RATE_LIMIT_EXEMPT_NETS
-
 	s, clk, server := startWithClock(t, "", map[string]string{
-		metricsToken:        token,
-		adminToken:          adminSecret,
-		rateLimitExemptNets: scraper,
+		metricsToken: token,
+		adminToken:   adminSecret,
 	})
 
 	const admins = `smallwebwaf_bans_made_total{cause="admin",instance="app"}`
 
-	wantMetric(t, s.scrape(scraper), admins, 0)
+	wantMetric(t, s.scrape(), admins, 0)
 
 	// As an admin's edit of bans.json that adds a ban is taken in.
 	server.Ledger.LoadEdit([]bans.Ban{{
@@ -269,11 +177,11 @@ func TestMetricsCountTheBansAnAdminMakes(t *testing.T) {
 		Start:    clk.Now(),
 	}})
 
-	wantMetric(t, s.scrape(scraper), admins, 1)
+	wantMetric(t, s.scrape(), admins, 1)
 
 	// And a ban made through the endpoint.
-	s.admin(http.MethodPost, proxy.BansPath, banOtherClient, http.StatusOK)
-	wantMetric(t, s.scrape(scraper), admins, 2)
+	s.admin(http.MethodPost, servewaf.BansPath, banOtherClient, http.StatusOK)
+	wantMetric(t, s.scrape(), admins, 2)
 }
 
 func TestMetricsByCountryKeepTheBusiestAndCountTheRestAsOther(t *testing.T) {
@@ -312,7 +220,7 @@ func TestMetricsByCountryKeepTheBusiestAndCountTheRestAsOther(t *testing.T) {
 			// Each is counted before the next is sent, so that the
 			// countries are ranked in the order sent.
 			lines++
-			out.requestLines(t, lines)
+			out.endedLines(t, lines)
 		}
 	}
 
@@ -321,7 +229,7 @@ func TestMetricsByCountryKeepTheBusiestAndCountTheRestAsOther(t *testing.T) {
 	send(fromDE, 2, http.StatusOK)
 	send(fromFR, 1, http.StatusOK)
 
-	metrics := scrape(t, addr)
+	metrics := scrape(t, server.Addr)
 	lines++
 
 	wantMetric(t, metrics,
@@ -349,7 +257,7 @@ func TestMetricsByCountryKeepTheBusiestAndCountTheRestAsOther(t *testing.T) {
 	// from then on, and DE's is gone.
 	send(fromFR, 3, http.StatusOK)
 
-	metrics = scrape(t, addr)
+	metrics = scrape(t, server.Addr)
 	wantMetric(t, metrics,
 		`smallwebwaf_country_requests_total{country="KP",instance="app"}`, 3)
 	wantMetric(t, metrics,
@@ -383,13 +291,12 @@ func TestMetricsByASNumberKeepTheBusiestAndCountTheRestAsOther(t *testing.T) {
 		answer(fromDE, "AS64501"), answer(fromKP, "AS64502"),
 	})
 
-	// With one AS number of its own, the other is counted as other. The
-	// metrics are asked for from a private address, which has no AS number.
+	// With one AS number of its own, the other is counted as other.
 	s.get(fromDE, http.StatusOK, requestlog.ActionForward)
 	s.get(fromDE, http.StatusOK, requestlog.ActionForward)
 	s.get(fromKP, http.StatusOK, requestlog.ActionForward)
 
-	metrics := s.scrape("10.0.0.9")
+	metrics := s.scrape()
 	wantMetric(t, metrics,
 		`smallwebwaf_asn_requests_total{asn="AS64501",instance="app"}`, 2)
 	wantMetric(t, metrics,
@@ -412,11 +319,12 @@ func TestMetricsCountGeoJSRequestsAndFailures(t *testing.T) {
 	t.Cleanup(geojs.Close)
 
 	app := startApp(t, func(http.ResponseWriter, *http.Request) {})
-	addr, _ := startProxyWithGeoJS(t, app.URL, geojs.URL, map[string]string{
-		trustedProxies:  trustLocalhost,
-		metricsToken:    token,
-		deniedCountries: "kp",
-	})
+	addr, _, server := startProxyWithClock(t, app.URL, geojs.URL, time.Now,
+		map[string]string{
+			trustedProxies:  trustLocalhost,
+			metricsToken:    token,
+			deniedCountries: "kp",
+		})
 
 	// GeoJS fails, so the client counts as coming from an unknown country,
 	// which SWWAF_DENIED_COUNTRIES does not refuse.
@@ -427,13 +335,13 @@ func TestMetricsCountGeoJSRequestsAndFailures(t *testing.T) {
 	// The client stops waiting for GeoJS once SWWAF_LOOKUP_TIMEOUT is up, so
 	// GeoJS's failure can come after its request has ended.
 	deadline := time.Now().Add(waitLimit)
-	metrics := scrape(t, addr)
+	metrics := scrape(t, server.Addr)
 
 	for metric(t, metrics, `smallwebwaf_geojs_failures_total{instance="app"}`) == 0 &&
 		time.Now().Before(deadline) {
 		time.Sleep(pollInterval)
 
-		metrics = scrape(t, addr)
+		metrics = scrape(t, server.Addr)
 	}
 
 	wantMetric(t, metrics, `smallwebwaf_geojs_requests_total{instance="app"}`, 1)
@@ -452,12 +360,12 @@ func keptAnswer(addr, country string) lookup.Answer {
 	}
 }
 
-// scrape asks smallwebwaf at addr for the metrics, with the token, and
-// returns them.
+// scrape asks servewaf at addr for the metrics, with the token, and returns
+// them.
 func scrape(t *testing.T, addr string) string {
 	t.Helper()
 
-	req := newRequest(t, http.MethodGet, addr, proxy.MetricsPath, http.NoBody)
+	req := newRequest(t, http.MethodGet, addr, servewaf.MetricsPath, http.NoBody)
 	req.Header.Set("Authorization", bearer)
 
 	got := do(t, req)
@@ -468,15 +376,12 @@ func scrape(t *testing.T, addr string) string {
 	return string(got.body)
 }
 
-// scrape asks for the metrics, with the token, from the client at from,
-// and returns them.
-func (s *sender) scrape(from string) string {
+// scrape asks for the metrics, with the token, and returns them.
+func (s *sender) scrape() string {
 	s.t.Helper()
 
-	_, metrics := s.requestWithHeader(from, proxy.MetricsPath, "Authorization: "+bearer,
-		http.StatusOK, requestlog.ActionAdmin)
-
-	return metrics
+	return string(s.adminRequest(bearer, http.MethodGet, servewaf.MetricsPath, "",
+		http.StatusOK).body)
 }
 
 // metric returns the value of series in metrics, which are in the
@@ -524,22 +429,3 @@ func wantNoSeries(t *testing.T, metrics, series string) {
 		t.Errorf("there is a series %s", series)
 	}
 }
-
-// wantLimitHits checks that the metrics of smallwebwaf at addr count hits
-// requests that passed the size or time limit of the setting limit, with
-// no series for it when hits is 0.
-func wantLimitHits(t *testing.T, addr, limit string, hits int) {
-	t.Helper()
-
-	series := `smallwebwaf_size_and_time_limit_hits_total{instance="app",limit="` +
-		limit + `"}`
-	metrics := scrape(t, addr)
-
-	if hits == 0 {
-		wantNoSeries(t, metrics, series)
-
-		return
-	}
-
-	wantMetric(t, metrics, series, float64(hits))
-}

internal/servewaf/observe_test.go

@@ -1,23 +1,31 @@
-package proxy_test
+package servewaf_test
 
 import (
-	"bytes"
-	"io"
 	"net/http"
 	"net/netip"
 	"reflect"
-	"sync/atomic"
 	"testing"
 	"time"
 
 	"sneak.berlin/go/smallwebwaf/internal/bans"
-	"sneak.berlin/go/smallwebwaf/internal/proxy"
 	"sneak.berlin/go/smallwebwaf/internal/requestlog"
 )
 
 // observe is the value of SWWAF_MODE for observe mode.
 const observe = "observe"
 
+func TestObserveModeNamesTheHeuristicThatWouldHaveRefused(t *testing.T) {
+	t.Parallel()
+
+	s, _, _ := startWithClock(t, "", map[string]string{
+		mode: observe, denyNets: client,
+	})
+
+	line := s.get(client, http.StatusOK, requestlog.ActionForward)
+	wantWouldAction(t, line, requestlog.ActionDenied)
+	wantHeuristic(t, line, "deny_nets", `{"netblock": "`+client+`/32"}`)
+}
+
 func TestObserveModeForwardsWhatEnforceModeRefuses(t *testing.T) {
 	t.Parallel()
 
@@ -76,11 +84,6 @@ func TestObserveModeForwardsWhatEnforceModeRefuses(t *testing.T) {
 				// Passed to the app, which answered it.
 				line := s.get(sent.from, http.StatusOK, requestlog.ActionForward)
 				wantWouldAction(t, line, sent.refusal)
-
-				if line.UpstreamStatus != http.StatusOK {
-					t.Errorf("log line has upstream_status %d, want 200",
-						line.UpstreamStatus)
-				}
 			}
 		})
 	}
@@ -133,62 +136,6 @@ func TestObserveModeMakesNoBanAndKeepsTheBansItHas(t *testing.T) {
 	}
 }
 
-func TestObserveModeKeepsTheSizeLimitsAndTheToken(t *testing.T) {
-	t.Parallel()
-
-	const denied = "192.0.2.50" // in SWWAF_DENY_NETS
-
-	var calls atomic.Int32
-
-	app := startApp(t, func(w http.ResponseWriter, _ *http.Request) {
-		calls.Add(1)
-		answerWithSize(w, 2*sizeLimit, true)
-	})
-	addr, out := startProxy(t, app.URL, map[string]string{
-		mode:             observe,
-		trustedProxies:   trustLocalhost,
-		denyNets:         denied,
-		requestMaxBytes:  sizeLimitSetting,
-		responseMaxBytes: sizeLimitSetting,
-		metricsToken:     token,
-	})
-
-	// SWWAF_DENY_NETS would refuse each request; instead a size limit or
-	// the missing token does.
-	for i, tc := range []struct {
-		method, path string
-		body         io.Reader
-		status       int
-		action       string
-	}{
-		{
-			http.MethodPost, "/upload", bytes.NewReader(make([]byte, 2*sizeLimit)),
-			http.StatusRequestEntityTooLarge, requestlog.ActionTooLarge,
-		},
-		{
-			http.MethodGet, "/download", http.NoBody,
-			http.StatusBadGateway, requestlog.ActionTooLarge,
-		},
-		{
-			http.MethodGet, proxy.MetricsPath, http.NoBody,
-			http.StatusUnauthorized, requestlog.ActionAdmin,
-		},
-	} {
-		req := newRequest(t, tc.method, addr, tc.path, tc.body)
-		req.Header.Set(forwardedFor, denied)
-		wantStatus(t, do(t, req), tc.status)
-
-		line := out.requestLines(t, i+1)[i]
-		wantLine(t, line, tc.status, tc.action)
-		wantWouldAction(t, line, requestlog.ActionDenied)
-	}
-
-	// The upload was refused before it reached the app.
-	if calls.Load() != 1 {
-		t.Errorf("the app was called %d times, want once", calls.Load())
-	}
-}
-
 // wantWouldAction checks the request log line's would_action, and that a
 // line that should have none has no such field.
 func wantWouldAction(t *testing.T, line logLine, want string) {

internal/servewaf/proxy.go

@@ -1,16 +1,12 @@
-// Package proxy runs the checks on each request and writes its request log
-// line. New passes each request it lets through to the app and the app's
-// answer back, unchanged, within the size and time limits. NewServeWAF instead
-// answers rproxy's question about each request, and takes rproxy's report once
-// the visitor's answer has ended, which writes the request a second log line.
-package proxy
+// Package servewaf is the server the servewaf command runs. It answers rproxy's
+// questions, takes rproxy's reports and answers its own endpoints, and writes a
+// log line for each.
+package servewaf
 
 import (
 	"io"
-	"log"
 	"log/slog"
 	"net/http"
-	"strings"
 	"time"
 
 	lru "github.com/hashicorp/golang-lru/v2"
@@ -27,18 +23,12 @@ import (
 	"sneak.berlin/go/smallwebwaf/internal/waf"
 )
 
-// How smallwebwaf keeps connections to the app open between requests.
-const (
-	appIdleConns       = 100
-	appIdleConnTimeout = 90 * time.Second
-)
-
-// adminPrefix starts the path of every request for smallwebwaf itself,
-// which never reaches the app.
+// adminPrefix starts the path of each of servewaf's own endpoints. The app never
+// sees a path under it.
 const adminPrefix = "/_smallwebwaf/"
 
-// HealthPath is smallwebwaf's health endpoint, which the container's
-// health check asks.
+// HealthPath is the health endpoint of servewaf and of rproxy, which the
+// container's health check asks.
 const HealthPath = "/_smallwebwaf/healthz"
 
 // MetricsPath is where the metrics are, for a request that carries
@@ -49,15 +39,15 @@ const MetricsPath = "/_smallwebwaf/metrics"
 // a client's address, lifts them, with SWWAF_ADMIN_TOKEN.
 const BansPath = "/_smallwebwaf/bans"
 
-// ClientsPath is where an admin asks what smallwebwaf knows of a client,
-// by the client's address after it, with SWWAF_ADMIN_TOKEN.
+// ClientsPath is where an admin asks what servewaf knows of a client, by the
+// client's address after it, with SWWAF_ADMIN_TOKEN.
 const ClientsPath = "/_smallwebwaf/clients/"
 
 // Params are what New needs.
 type Params struct {
 	Config *config.Config
-	// RequestLog receives one JSON line per request, and from servewaf a second
-	// when the request's report comes.
+	// RequestLog receives two JSON lines per question, one at its decision and
+	// one when its report comes, and one per request to servewaf's own endpoints.
 	RequestLog io.Writer
 	// ProcessLog receives the process's own messages.
 	ProcessLog *slog.Logger
@@ -77,7 +67,7 @@ type Params struct {
 	// Rules are the rule files' rules, which each request is checked
 	// against.
 	Rules *rules.Files
-	// Alerts receive the alert for each ban the proxy makes or makes
+	// Alerts receive the alert for each ban servewaf makes or makes
 	// permanent, for each count over an anomaly threshold, for each request
 	// whose client a blocklist, the CrowdSec decision list, a DNSBL zone or
 	// AbuseIPDB lists, for each request the Core Rule Set scores at or over
@@ -87,11 +77,10 @@ type Params struct {
 	Alerts *alerts.Queue
 }
 
-// Server is the server smallwebwaf runs, with the parts of the proxy
-// whose state the state files keep, the lookup database, nil unless
-// SWWAF_LOOKUP_SOURCE is file, the lists fetched from URLs, which its Run
-// fetches, the DNSBL zones' verdicts, AbuseIPDB's scores and checks
-// spent, and the metrics.
+// Server is the server servewaf runs, with the parts whose state the state
+// files keep, the lookup database, nil unless SWWAF_LOOKUP_SOURCE is file, the
+// lists fetched from URLs, which its Run fetches, the DNSBL zones' verdicts,
+// AbuseIPDB's scores and checks spent, and the metrics.
 type Server struct {
 	*http.Server
 
@@ -106,41 +95,24 @@ type Server struct {
 	Metrics    *metrics.Metrics
 }
 
-// New returns the server smallwebwaf runs: each request it reads passes
-// through the proxy. Go's server itself refuses a request line and
-// headers over SWWAF_CLIENT_REQUEST_HEADER_MAX_BYTES, with 431, closes a
-// connection idle for SWWAF_CLIENT_IDLE_TIMEOUT, and applies
-// SWWAF_CLIENT_REQUEST_TIMEOUT while the headers arrive; the proxy
-// applies the timeouts and size limits from then on.
-func New(params Params) *Server {
-	h := newHandler(params)
-
-	return h.server(&http.Server{
-		Handler:           h,
-		ReadHeaderTimeout: params.Config.ClientRequestTimeout,
-		// Off is an IdleTimeout of 0, which Go's server replaces with
-		// ReadTimeout: no limit, as long as ReadTimeout stays unset.
-		IdleTimeout: params.Config.ClientIdleTimeout,
-		// Go's server reads 4 KiB past MaxHeaderBytes before it
-		// refuses, so the limit a client meets is the setting.
-		MaxHeaderBytes: int(params.Config.ClientRequestHeaderMaxBytes - 4<<10),
-	})
-}
-
 // newHandler returns the handler with what every request shares, as the
 // settings in params make it.
 func newHandler(params Params) *handler {
-	errorLog := slog.NewLogLogger(params.ProcessLog.Handler(), slog.LevelWarn)
 	m := metrics.New(params.Config.MetricsTopN, params.Config.InstanceName)
 	lists, dnsbl, abuseIPDB := newReputation(params, m)
+
+	awaitingReport, err := lru.New[string, *decision](maxAwaitingReport)
+	if err != nil {
+		panic(err) // New fails only for a size below one
+	}
+
 	h := &handler{
-		config:     params.Config,
-		requestLog: params.RequestLog,
-		processLog: params.ProcessLog,
-		errorLog:   errorLog,
-		transport:  newTransport(),
-		now:        params.Now,
-		metrics:    m,
+		config:         params.Config,
+		requestLog:     params.RequestLog,
+		processLog:     params.ProcessLog,
+		now:            params.Now,
+		metrics:        m,
+		awaitingReport: awaitingReport,
 		limiter: ratelimit.New(ratelimit.Limits{
 			PerMinute:      params.Config.RateLimitPerMinute,
 			PerHour:        params.Config.RateLimitPerHour,
@@ -232,7 +204,10 @@ func newReputation(
 
 // newCoreRuleSet returns the Core Rule Set at SWWAF_WAF_PARANOIA_LEVEL,
 // without the rules SWWAF_WAF_DISABLED_RULES switches off, reading bodies
-// up to SWWAF_WAF_BODY_LIMIT, or nil while SWWAF_WAF_MODE is off.
+// up to SWWAF_WAF_BODY_LIMIT, or nil while SWWAF_WAF_MODE is off. It reads at
+// most QuestionBodyMaxBytes less one byte: a question's body of
+// QuestionBodyMaxBytes may be cut short, and the Core Rule Set does not read a
+// JSON or XML body over its limit.
 func newCoreRuleSet(cfg *config.Config) *waf.CoreRuleSet {
 	if cfg.WAFMode == config.WAFModeOff {
 		return nil
@@ -240,26 +215,24 @@ func newCoreRuleSet(cfg *config.Config) *waf.CoreRuleSet {
 
 	coreRuleSet, err := waf.New(waf.Params{
 		ParanoiaLevel: cfg.WAFParanoiaLevel, DisabledRules: cfg.WAFDisabledRules,
-		BodyLimit: cfg.WAFBodyLimit,
+		BodyLimit: min(cfg.WAFBodyLimit, QuestionBodyMaxBytes-1),
 	})
 	if err != nil {
 		// The Core Rule Set is built in, and the settings cannot break it:
-		// the paranoia level is from 1 to 4, the body limit at most 1G, and
-		// the id of no rule switches nothing off.
+		// the paranoia level is from 1 to 4, and the id of no rule switches
+		// nothing off.
 		panic(err)
 	}
 
 	return coreRuleSet
 }
 
-// handler is the proxy. It holds what every request shares; what belongs
-// to one request is in a request.
+// handler is servewaf's handler. It holds what every request shares; what
+// belongs to one request is in a request.
 type handler struct {
 	config      *config.Config
 	requestLog  io.Writer
 	processLog  *slog.Logger
-	errorLog    *log.Logger
-	transport   http.RoundTripper
 	now         func() time.Time
 	metrics     *metrics.Metrics
 	limiter     *ratelimit.Limiter
@@ -273,88 +246,7 @@ type handler struct {
 	rules       *rules.Files
 	coreRuleSet *waf.CoreRuleSet
 	alerts      *alerts.Queue
-	// awaitingReport holds, in servewaf, the decision on each answered
-	// question by its id until its report comes, and nil for a question still
-	// being handled.
+	// awaitingReport holds the decision on each answered question by its id
+	// until its report comes, and nil for a question still being handled.
 	awaitingReport *lru.Cache[string, *decision]
 }
-
-// newTransport returns what carries requests to the app. It never goes
-// through a proxy named in the environment, and leaves the app's answers
-// compressed or not as the app sent them.
-func newTransport() *http.Transport {
-	return &http.Transport{
-		MaxIdleConns:        appIdleConns,
-		MaxIdleConnsPerHost: appIdleConns,
-		IdleConnTimeout:     appIdleConnTimeout,
-		DisableCompression:  true,
-	}
-}
-
-// ServeHTTP handles one request: it works out the client, runs the
-// checks, passes the request to the app and the answer back within the
-// limits, or answers it itself if it is for smallwebwaf, and writes the
-// request's log line.
-func (h *handler) ServeHTTP(w http.ResponseWriter, r *http.Request) {
-	rq := h.newRequest(w, r)
-	defer rq.finish()
-
-	// The health endpoint is answered at once, before any check, so that
-	// a health checker is never refused. It does not ask the app.
-	if r.Method == http.MethodGet && r.URL.Path == HealthPath {
-		rq.answerHealth()
-
-		return
-	}
-
-	// Once the request has ended, before its log line is written. The
-	// last deferred runs first: countRefusal before addToHistory, so that
-	// a broken error burst is in the client's history.
-	defer rq.addToHistory()
-	defer rq.countAnomalies()
-	defer rq.countRefusal()
-
-	refused := rq.check(r.Context())
-	rq.checked = time.Now()
-
-	if refused != nil {
-		rq.answer(*refused)
-
-		return
-	}
-
-	// A request for smallwebwaf itself is answered where another would be
-	// passed to the app, so that it goes through every check first.
-	if strings.HasPrefix(r.URL.Path, adminPrefix) {
-		rq.answerAdmin()
-
-		return
-	}
-
-	// Once the response has ended, before the request is added to its
-	// client's history. Deferred, since ReverseProxy panics to end a
-	// response it cannot finish.
-	defer rq.countBytes()
-
-	rq.forward(r.Context())
-}
-
-// server returns the Server of h, which listens at SWWAF_LISTEN_ADDR and
-// logs through h, with what httpServer sets.
-func (h *handler) server(httpServer *http.Server) *Server {
-	httpServer.Addr = h.config.ListenAddr
-	httpServer.ErrorLog = h.errorLog
-
-	return &Server{
-		Server:     httpServer,
-		Ledger:     h.ledger,
-		Limiter:    h.limiter,
-		GeoJS:      h.geojs,
-		Anomalies:  h.anomalies,
-		LookupFile: h.lookupFile,
-		Lists:      h.lists,
-		DNSBL:      h.dnsbl,
-		AbuseIPDB:  h.abuseIPDB,
-		Metrics:    h.metrics,
-	}
-}

internal/servewaf/proxy_test.go

@@ -1,10 +1,11 @@
-package proxy_test
+package servewaf_test
 
 import (
 	"bufio"
 	"bytes"
 	"encoding/json"
 	"io"
+	"log/slog"
 	"maps"
 	"net"
 	"net/http"
@@ -17,75 +18,70 @@ import (
 	"sneak.berlin/go/smallwebwaf/internal/alerts"
 	"sneak.berlin/go/smallwebwaf/internal/config"
 	"sneak.berlin/go/smallwebwaf/internal/lookup"
-	"sneak.berlin/go/smallwebwaf/internal/proxy"
 	"sneak.berlin/go/smallwebwaf/internal/requestlog"
+	"sneak.berlin/go/smallwebwaf/internal/rproxy"
 	"sneak.berlin/go/smallwebwaf/internal/rules"
+	"sneak.berlin/go/smallwebwaf/internal/servewaf"
 )
 
 const (
-	// shortTimeout is what a test sets a timeout to, to see it run out.
-	// It starts before the test has set up its case, such as an upgrade
-	// or the app's buffers filling, so it is as long as the hold-up of the
-	// test process that wantTimedOut allows: a shorter one can run out
-	// first on a busy host.
-	shortTimeout = waitLimit / 2
-	// longTimeoutSetting is a timeout that does not run out in a test.
-	longTimeoutSetting = "1m"
 	// waitLimit bounds how long a test waits for what should happen.
 	waitLimit = 10 * time.Second
 	// pollInterval is how often a test looks for a log line.
 	pollInterval = 10 * time.Millisecond
-	// localhost is where every test server listens, and so the address
-	// smallwebwaf sees each test's requests come from.
+	// localhost is where every test server listens, and so the address rproxy
+	// sees each test's requests come from.
 	localhost = "127.0.0.1"
 	// requestType is the type that marks a request log line.
 	requestType = "request"
-	// protocol is the protocol of every test's requests.
+	// protocol is the protocol of every question.
 	protocol = "HTTP/1.1"
+	// trustLocalhost trusts the address every test connects from, and a
+	// network for proxies in front of it.
+	trustLocalhost = localhost + "/32,10.0.0.0/8"
+	// appHost is the host every test asks for.
+	appHost = "app.example"
+	// client is the client's address, as a proxy names it.
+	client = "203.0.113.9"
+	// forwardedFor is the header that lists the client and its proxies,
+	// and forwardedProto the one that gives the scheme the client used.
+	forwardedFor   = "X-Forwarded-For"
+	forwardedProto = "X-Forwarded-Proto"
+	// secure is the scheme a client reached traefik with, and plain the one
+	// rproxy serves.
+	secure = "https"
+	plain  = "http"
 )
 
-// shortTimeoutSetting is shortTimeout as a setting's value.
-//
-//nolint:gochecknoglobals // a constant cannot call String
-var shortTimeoutSetting = shortTimeout.String()
-
 // The settings the tests set.
 const (
-	clientRequestTimeout    = "SWWAF_CLIENT_REQUEST_TIMEOUT"
-	clientHeaderMaxBytes    = "SWWAF_CLIENT_REQUEST_HEADER_MAX_BYTES"
-	clientIdleTimeout       = "SWWAF_CLIENT_IDLE_TIMEOUT"
-	clientResponseTimeout   = "SWWAF_CLIENT_RESPONSE_TIMEOUT"
-	upstreamRequestTimeout  = "SWWAF_UPSTREAM_REQUEST_TIMEOUT"
-	upstreamResponseTimeout = "SWWAF_UPSTREAM_RESPONSE_TIMEOUT"
-	mode                    = "SWWAF_MODE"
-	requestMaxBytes         = "SWWAF_REQUEST_MAX_BYTES"
-	responseMaxBytes        = "SWWAF_RESPONSE_MAX_BYTES"
-	trustedProxies          = "SWWAF_TRUSTED_PROXIES"
-	ipv6GroupPrefix         = "SWWAF_IPV6_GROUP_PREFIX"
-	maxTrackedClients       = "SWWAF_MAX_TRACKED_CLIENTS"
-	allowNets               = "SWWAF_ALLOW_NETS"
-	rateLimitExemptNets     = "SWWAF_RATE_LIMIT_EXEMPT_NETS"
-	denyNets                = "SWWAF_DENY_NETS"
-	rateLimitPerMinute      = "SWWAF_RATE_LIMIT_PER_MINUTE"
-	rateLimitPerDay         = "SWWAF_RATE_LIMIT_PER_DAY"
-	rateLimitExemptPaths    = "SWWAF_RATE_LIMIT_EXEMPT_PATHS"
-	lookupSource            = "SWWAF_LOOKUP_SOURCE"
-	lookupDBPath            = "SWWAF_LOOKUP_DB_PATH"
-	lookupTimeout           = "SWWAF_LOOKUP_TIMEOUT"
-	addLookupHeaders        = "SWWAF_ADD_LOOKUP_HEADERS"
-	deniedCountries         = "SWWAF_DENIED_COUNTRIES"
-	allowedCountries        = "SWWAF_EXCLUSIVELY_ALLOWED_COUNTRIES"
-	banResponse             = "SWWAF_BAN_RESPONSE"
-	limitBanDuration        = "SWWAF_LIMIT_BAN_DURATION"
-	limitBanRepeatWindow    = "SWWAF_LIMIT_BAN_REPEAT_WINDOW"
-	maxBanDuration          = "SWWAF_MAX_BAN_DURATION"
-	maxBans                 = "SWWAF_MAX_BANS"
-	banScopeV4Prefix        = "SWWAF_BAN_SCOPE_V4_PREFIX"
-	instanceName            = "SWWAF_INSTANCE_NAME"
-	logRequestHeaders       = "SWWAF_LOG_REQUEST_HEADERS"
-	attackBanDuration       = "SWWAF_ATTACK_BAN_DURATION"
-	rulesDir                = "SWWAF_RULES_DIR"
-	wafMode                 = "SWWAF_WAF_MODE"
+	mode                 = "SWWAF_MODE"
+	trustedProxies       = "SWRP_TRUSTED_PROXIES"
+	ipv6GroupPrefix      = "SWWAF_IPV6_GROUP_PREFIX"
+	maxTrackedClients    = "SWWAF_MAX_TRACKED_CLIENTS"
+	allowNets            = "SWWAF_ALLOW_NETS"
+	rateLimitExemptNets  = "SWWAF_RATE_LIMIT_EXEMPT_NETS"
+	denyNets             = "SWWAF_DENY_NETS"
+	rateLimitPerMinute   = "SWWAF_RATE_LIMIT_PER_MINUTE"
+	rateLimitPerDay      = "SWWAF_RATE_LIMIT_PER_DAY"
+	rateLimitExemptPaths = "SWWAF_RATE_LIMIT_EXEMPT_PATHS"
+	lookupSource         = "SWWAF_LOOKUP_SOURCE"
+	lookupDBPath         = "SWWAF_LOOKUP_DB_PATH"
+	lookupTimeout        = "SWWAF_LOOKUP_TIMEOUT"
+	addLookupHeaders     = "SWWAF_ADD_LOOKUP_HEADERS"
+	deniedCountries      = "SWWAF_DENIED_COUNTRIES"
+	allowedCountries     = "SWWAF_EXCLUSIVELY_ALLOWED_COUNTRIES"
+	banResponse          = "SWWAF_BAN_RESPONSE"
+	limitBanDuration     = "SWWAF_LIMIT_BAN_DURATION"
+	limitBanRepeatWindow = "SWWAF_LIMIT_BAN_REPEAT_WINDOW"
+	maxBanDuration       = "SWWAF_MAX_BAN_DURATION"
+	maxBans              = "SWWAF_MAX_BANS"
+	banScopeV4Prefix     = "SWWAF_BAN_SCOPE_V4_PREFIX"
+	instanceName         = "SWWAF_INSTANCE_NAME"
+	logRequestHeaders    = "SWWAF_LOG_REQUEST_HEADERS"
+	attackBanDuration    = "SWWAF_ATTACK_BAN_DURATION"
+	rulesDir             = "SWWAF_RULES_DIR"
+	wafMode              = "SWWAF_WAF_MODE"
 )
 
 // off is the value that switches a setting off.
@@ -179,6 +175,73 @@ func (o *output) requestLine(t *testing.T) logLine {
 	return o.requestLines(t, 1)[0]
 }
 
+// endedLines waits for count requests that went through rproxy, or to servewaf's
+// own endpoints, to have ended, and returns the last log line of each, in the
+// order servewaf took them. A question's last line is the one its report writes.
+func (o *output) endedLines(t *testing.T, count int) []logLine {
+	t.Helper()
+
+	deadline := time.Now().Add(waitLimit)
+	for time.Now().Before(deadline) {
+		found := o.lastLines(t)
+
+		ended := len(found) >= count
+		for _, line := range found[:min(count, len(found))] {
+			if line.ServeWAFLine == requestlog.ServeWAFLineDecision {
+				ended = false
+			}
+		}
+
+		if ended {
+			return found
+		}
+
+		time.Sleep(pollInterval)
+	}
+
+	t.Fatalf("fewer than %d requests have ended after %s", count, waitLimit)
+
+	return nil
+}
+
+// lastLines returns the last request log line written so far of each request,
+// in the order servewaf took them.
+func (o *output) lastLines(t *testing.T) []logLine {
+	t.Helper()
+
+	var found []logLine
+
+	places := map[string]int{}
+
+	for _, fields := range o.lines(t) {
+		if fields["type"] != requestType {
+			continue
+		}
+
+		line := decodeLine(t, fields)
+
+		place, seen := places[line.RequestID]
+		if seen {
+			found[place] = line
+
+			continue
+		}
+
+		places[line.RequestID] = len(found)
+		found = append(found, line)
+	}
+
+	return found
+}
+
+// endedLine waits for a test's one request to have ended, and returns its last
+// log line.
+func (o *output) endedLine(t *testing.T) logLine {
+	t.Helper()
+
+	return o.endedLines(t, 1)[0]
+}
+
 // decodeLine reads a request log line's fields into a logLine.
 func decodeLine(t *testing.T, fields map[string]any) logLine {
 	t.Helper()
@@ -198,7 +261,7 @@ func decodeLine(t *testing.T, fields map[string]any) logLine {
 	return line
 }
 
-// startApp starts app as the app smallwebwaf passes requests to.
+// startApp starts app as the app rproxy passes requests to.
 func startApp(t *testing.T, app http.HandlerFunc) *httptest.Server {
 	t.Helper()
 
@@ -208,9 +271,9 @@ func startApp(t *testing.T, app http.HandlerFunc) *httptest.Server {
 	return server
 }
 
-// startProxy starts smallwebwaf in front of the app at appURL, with the
-// settings in env on top of the defaults, and returns where it listens and
-// what it writes.
+// startProxy starts servewaf, and rproxy in front of the app at appURL, each with
+// the settings in env on top of the defaults, and returns where rproxy listens
+// and what servewaf writes.
 func startProxy(t *testing.T, appURL string, env map[string]string) (string, *output) {
 	t.Helper()
 
@@ -230,14 +293,14 @@ func startProxyWithGeoJS(
 }
 
 // startProxyWithClock is startProxyWithGeoJS with requests counted and
-// bans made by the time now tells, and returns the server as well. Unless
-// env sets SWWAF_RULES_DIR, it is an empty directory, of no rules, and
-// unless it sets SWWAF_INSTANCE_NAME, that is app, the label instance of
-// every metric.
+// bans made by the time now tells, and returns servewaf's server as well, whose
+// Addr is where servewaf listens. Unless env sets SWWAF_RULES_DIR, it is an empty
+// directory, of no rules, and unless it sets SWWAF_INSTANCE_NAME, that is app,
+// the label instance of every metric.
 func startProxyWithClock(
 	t *testing.T, appURL, geojsURL string, now func() time.Time,
 	env map[string]string,
-) (string, *output, *proxy.Server) {
+) (string, *output, *servewaf.Server) {
 	t.Helper()
 
 	addr, out, server, _ := startProxyWithAlerts(t, appURL, geojsURL, now, env)
@@ -246,14 +309,70 @@ func startProxyWithClock(
 }
 
 // startProxyWithAlerts is startProxyWithClock, and returns the queue of
-// the alerts the proxy raises as well, as newProxy makes them.
+// the alerts servewaf raises as well, as newServeWAF makes them.
 func startProxyWithAlerts(
 	t *testing.T, appURL, geojsURL string, now func() time.Time,
 	env map[string]string,
-) (string, *output, *proxy.Server, *alerts.Queue) {
+) (string, *output, *servewaf.Server, *alerts.Queue) {
 	t.Helper()
 
-	server, out, alertQueue := newProxy(t, appURL, geojsURL, now, env)
+	server, out, alertQueue := newServeWAF(t, geojsURL, now, env)
+	serve(t, server)
+
+	return startRProxy(t, server.Addr, appURL, env), out, server, alertQueue
+}
+
+// serve serves server on a port of its own until the test ends, and sets its
+// Addr to where it listens.
+func serve(t *testing.T, server *servewaf.Server) {
+	t.Helper()
+
+	listener, err := (&net.ListenConfig{}).Listen(t.Context(), "tcp", localhost+":0")
+	if err != nil {
+		t.Fatalf("listen: %v", err)
+	}
+
+	server.Addr = listener.Addr().String()
+
+	go func() {
+		_ = server.Serve(listener)
+	}()
+
+	t.Cleanup(func() {
+		_ = server.Close()
+	})
+}
+
+// startRProxy starts rproxy in front of the app at appURL, asking the servewaf
+// at serveWAFAddr, with the settings in env on top of the defaults, and returns
+// where it listens. What it writes is dropped. SWRP_TIMEOUT_MS is a minute unless
+// env sets it, so that on a busy host SWRP_DEFAULT_DISPOSITION does not decide.
+func startRProxy(
+	t *testing.T, serveWAFAddr, appURL string, env map[string]string,
+) string {
+	t.Helper()
+
+	settings := map[string]string{
+		"SWRP_WAF_BACKEND":  "http://" + serveWAFAddr,
+		"SWRP_UPSTREAM_URL": appURL,
+		"SWRP_TIMEOUT_MS":   "60000",
+	}
+	maps.Copy(settings, env)
+
+	cfg, err := config.RProxyFromEnvironment(func(name string) (string, bool) {
+		value, ok := settings[name]
+
+		return value, ok
+	})
+	if err != nil {
+		t.Fatalf("settings %v: %v", settings, err)
+	}
+
+	server := rproxy.New(rproxy.Params{
+		Config:     cfg,
+		RequestLog: io.Discard,
+		ProcessLog: requestlog.NewProcessLogger(io.Discard, "rproxy", slog.LevelInfo),
+	})
 
 	listener, err := (&net.ListenConfig{}).Listen(t.Context(), "tcp", localhost+":0")
 	if err != nil {
@@ -268,38 +387,35 @@ func startProxyWithAlerts(
 		_ = server.Close()
 	})
 
-	return listener.Addr().String(), out, server, alertQueue
+	return listener.Addr().String()
 }
 
-// newProxy makes the server startProxyWithClock starts, without starting
-// it, and returns it, what it writes, and the queue of the alerts the
-// proxy raises, as the settings in env make it. No alert is sent from the
-// queue: they wait in it, for the test to look at. With no geojsURL, there
-// is no stand-in for GeoJS to look clients up at, and SWWAF_LOOKUP_SOURCE
-// is off unless env sets it. While it is file, the lookup database
-// SWWAF_LOOKUP_DB_PATH names is read. Clients are checked with AbuseIPDB
-// at abuseIPDBURL while env sets SWWAF_ABUSEIPDB_KEY. SWWAF_WAF_MODE is off
-// unless env sets it, so that only the tests of the Core Rule Set have
-// their requests inspected by it.
-func newProxy(
-	t *testing.T, appURL, geojsURL string, now func() time.Time,
-	env map[string]string,
-) (*proxy.Server, *output, *alerts.Queue) {
+// newServeWAF makes servewaf's server, without starting it, and returns it, what
+// it writes, and the queue of the alerts it raises, as the settings in env make
+// it. No alert is sent from the queue: they wait in it, for the test to look at.
+// With no geojsURL, there is no stand-in for GeoJS to look clients up at, and
+// SWWAF_LOOKUP_SOURCE is off unless env sets it. While it is file, the lookup
+// database SWWAF_LOOKUP_DB_PATH names is read. Clients are checked with AbuseIPDB
+// at abuseIPDBURL while env sets SWWAF_ABUSEIPDB_KEY. SWWAF_WAF_MODE is off unless
+// env sets it, so that only the tests of the Core Rule Set have their requests
+// inspected by it.
+func newServeWAF(
+	t *testing.T, geojsURL string, now func() time.Time, env map[string]string,
+) (*servewaf.Server, *output, *alerts.Queue) {
 	t.Helper()
 
-	return newServerWith(t, proxy.New, appURL, geojsURL, now, env)
+	return newServeWAFWith(t, servewaf.New, geojsURL, now, env)
 }
 
-// newServerWith is newProxy for the server build makes.
-func newServerWith(
-	t *testing.T, build func(proxy.Params) *proxy.Server,
-	appURL, geojsURL string, now func() time.Time, env map[string]string,
-) (*proxy.Server, *output, *alerts.Queue) {
+// newServeWAFWith is newServeWAF for the server build makes.
+func newServeWAFWith(
+	t *testing.T, build func(servewaf.Params) *servewaf.Server,
+	geojsURL string, now func() time.Time, env map[string]string,
+) (*servewaf.Server, *output, *alerts.Queue) {
 	t.Helper()
 
 	settings := map[string]string{
-		"SWWAF_UPSTREAM_URL": appURL, rulesDir: t.TempDir(), instanceName: "app",
-		wafMode: off,
+		rulesDir: t.TempDir(), instanceName: "app", wafMode: off,
 	}
 	if geojsURL == "" {
 		settings[lookupSource] = off
@@ -347,7 +463,7 @@ func newServerWith(
 		}
 	}
 
-	server := build(proxy.Params{
+	server := build(servewaf.Params{
 		Config:       cfg,
 		RequestLog:   out,
 		ProcessLog:   processLog,
@@ -391,7 +507,7 @@ func readAnswer(res *http.Response) answer {
 	return answer{status: res.StatusCode, header: res.Header, body: body, err: err}
 }
 
-// newRequest makes a request for path to smallwebwaf at addr.
+// newRequest makes a request for path to addr, where rproxy or servewaf listens.
 func newRequest(t *testing.T, method, addr, path string, body io.Reader) *http.Request {
 	t.Helper()
 
@@ -415,15 +531,15 @@ func do(t *testing.T, req *http.Request) answer {
 	return readAnswer(res)
 }
 
-// get sends a GET request for path to smallwebwaf at addr.
+// get sends a GET request for path to addr.
 func get(t *testing.T, addr, path string) answer {
 	t.Helper()
 
 	return do(t, newRequest(t, http.MethodGet, addr, path, http.NoBody))
 }
 
-// dial opens a connection to smallwebwaf at addr, for requests the HTTP
-// client cannot make, such as one that stops sending halfway.
+// dial opens a connection to addr, for requests the HTTP client cannot make,
+// such as one that stops sending halfway.
 func dial(t *testing.T, addr string) net.Conn {
 	t.Helper()
 
@@ -484,14 +600,3 @@ func wantStatus(t *testing.T, got answer, status int) {
 		t.Errorf("status %d, want %d", got.status, status)
 	}
 }
-
-// wantTimedOut checks that what began at start ended once shortTimeout
-// had run out, and not much later.
-func wantTimedOut(t *testing.T, start time.Time) {
-	t.Helper()
-
-	took := time.Since(start)
-	if took < shortTimeout || took > shortTimeout+waitLimit/2 {
-		t.Errorf("took %s, want %s", took, shortTimeout)
-	}
-}

internal/servewaf/ratelimits.go

@@ -0,0 +1,65 @@
+package servewaf
+
+// The heuristic rate_limits. It reads SWWAF_RATE_LIMIT_EXEMPT_NETS,
+// SWWAF_RATE_LIMIT_EXEMPT_PATHS and SWWAF_BAN_RESPONSE, and the rate limits and
+// biased thresholds through the limiter and limitPercentages.
+
+import (
+	"context"
+	"time"
+
+	"sneak.berlin/go/smallwebwaf/internal/requestlog"
+)
+
+// rateLimits counts the request for the rate limits, unless
+// countedByRateLimits exempts it, by the client's limit percentages, which it
+// notes for the log line with the client's counts. A request that takes the
+// client over a rate limit, as its limit percentage lowers it, breaks it: it is
+// refused, and bans the client. A request exempt from the rate limits is exempt
+// from the byte limits too. Its figures are the window, the count and the
+// limit.
+type rateLimits struct{}
+
+func (rateLimits) name() string { return "rate_limits" }
+
+func (rateLimits) check(_ context.Context, rq *request, now time.Time) *verdict {
+	rq.counted = rq.countedByRateLimits()
+	if !rq.counted {
+		return nil
+	}
+
+	rq.limitPercent, rq.bytesPercent = rq.limitPercentages()
+	rq.line.LimitPercent, rq.line.LimitPercentSetting = rq.limitPercent.logged()
+	rq.line.BytesPercent, rq.line.BytesPercentSetting = rq.bytesPercent.logged()
+
+	counts, hit, over := rq.h.limiter.Count(rq.h.clientGroup(rq.client), now,
+		rq.limitPercent.percent)
+	rq.line.Counts = counts
+
+	if !over {
+		return nil
+	}
+
+	rq.banForLimit(now, hit, rq.h.config.BanResponse)
+
+	return &verdict{action: requestlog.ActionRateLimited, figures: limitFigures(hit)}
+}
+
+// overAWholeRateLimit reports whether the heuristic rate_limits will refuse the
+// request at now, whatever its client's limit percentages: the rate limits
+// count it, and one more request from its client takes it over a whole rate
+// limit. It counts nothing.
+func (rq *request) overAWholeRateLimit(now time.Time) bool {
+	return rq.countedByRateLimits() &&
+		rq.h.limiter.OverARateLimit(rq.h.clientGroup(rq.client), now)
+}
+
+// countedByRateLimits reports whether the rate limits count the request: its
+// client is not in SWWAF_RATE_LIMIT_EXEMPT_NETS, and its path is not exempt
+// under SWWAF_RATE_LIMIT_EXEMPT_PATHS.
+func (rq *request) countedByRateLimits() bool {
+	cfg := rq.h.config
+
+	return !isInside(rq.client, cfg.RateLimitExemptNets) &&
+		!pathExempt(rq.in, cfg.RateLimitExemptPaths)
+}

internal/servewaf/ratelimits_test.go

@@ -1,4 +1,4 @@
-package proxy_test
+package servewaf_test
 
 import (
 	"net/http"
@@ -51,7 +51,7 @@ func TestRateLimitRefusesBeforeTheApp(t *testing.T) {
 		req.Header.Set(forwardedFor, sent.client)
 		wantStatus(t, do(t, req), sent.want)
 
-		line := out.requestLines(t, i+1)[i]
+		line := out.endedLines(t, i+1)[i]
 		if line.ClientIP != sent.logged {
 			t.Errorf("log line has client_ip %q, want %q", line.ClientIP, sent.logged)
 		}
@@ -72,6 +72,17 @@ func TestRateLimitRefusesBeforeTheApp(t *testing.T) {
 	}
 }
 
+func TestRateLimitRefusalNamesItsHeuristicWindowCountAndLimit(t *testing.T) {
+	t.Parallel()
+
+	s, _, _ := startWithClock(t, "", map[string]string{rateLimitPerMinute: "1"})
+
+	s.get(client, http.StatusOK, requestlog.ActionForward)
+
+	line := s.get(client, http.StatusForbidden, requestlog.ActionRateLimited)
+	wantHeuristic(t, line, "rate_limits", `{"window": "minute", "count": 2, "limit": 1}`)
+}
+
 func TestIPv6GroupPrefixSetsTheClientTheLimitsCount(t *testing.T) {
 	t.Parallel()
 

internal/servewaf/refusallimit.go

@@ -0,0 +1,54 @@
+package servewaf
+
+// The heuristic refusal_limit. It reads SWWAF_ERROR_BURST_THRESHOLD and
+// SWWAF_BAN_RESPONSE.
+
+import (
+	"context"
+	"net/http"
+	"time"
+
+	"sneak.berlin/go/smallwebwaf/internal/requestlog"
+)
+
+// refusalLimit counts the request once it has been answered, if servewaf
+// refused it after a rule file match, a trap path or a Core Rule Set match, and
+// in observe mode if enforce mode would have: more than
+// SWWAF_ERROR_BURST_THRESHOLD such refusals of the client within a minute break
+// a limit, which bans the client. A client in SWWAF_ALLOW_NETS, which the
+// heuristics skip, is not counted, and nothing is while the threshold is off.
+// Its figures are the window, the count and the limit.
+type refusalLimit struct{}
+
+func (refusalLimit) name() string { return "refusal_limit" }
+
+func (refusalLimit) check(_ context.Context, rq *request, now time.Time) *verdict {
+	cfg := rq.h.config
+	if cfg.ErrorBurstThreshold == 0 {
+		return nil
+	}
+
+	if !rq.attack && !rq.ruleBlocked && !rq.wafBlocked {
+		return nil
+	}
+
+	hit, over := rq.h.limiter.CountRefusal(rq.h.clientGroup(rq.client), now,
+		cfg.ErrorBurstThreshold)
+	if !over {
+		return nil
+	}
+
+	// What the client was sent, or in observe mode would have been.
+	status := rq.out.status
+
+	switch rq.line.WouldAction {
+	case requestlog.ActionRuleBlocked, requestlog.ActionWAFBlocked:
+		status = http.StatusForbidden
+	case requestlog.ActionBanned:
+		status = cfg.BanResponse
+	}
+
+	rq.banForLimit(now, hit, status)
+
+	return &verdict{action: requestlog.ActionBanned, figures: limitFigures(hit)}
+}

internal/servewaf/refusallimit_test.go

@@ -1,4 +1,4 @@
-package proxy_test
+package servewaf_test
 
 import (
 	"maps"
@@ -10,15 +10,15 @@ import (
 
 	"sneak.berlin/go/smallwebwaf/internal/alerts"
 	"sneak.berlin/go/smallwebwaf/internal/bans"
-	"sneak.berlin/go/smallwebwaf/internal/proxy"
 	"sneak.berlin/go/smallwebwaf/internal/ratelimit"
 	"sneak.berlin/go/smallwebwaf/internal/requestlog"
+	"sneak.berlin/go/smallwebwaf/internal/servewaf"
 )
 
 const errorBurstThreshold = "SWWAF_ERROR_BURST_THRESHOLD"
 
-// refused is a request the tests here send, which smallwebwaf refuses
-// after a rule file match, or for a missing or wrong token.
+// refused is a request the tests here send, which servewaf refuses after a rule
+// file match.
 type refused int
 
 const (
@@ -27,11 +27,6 @@ const (
 	// banRule is one its ban rule refuses with 403, and bans the client
 	// for.
 	banRule
-	// noMetricsToken is one for the metrics without a token, and
-	// wrongAdminToken one for the bans with the metrics token, each
-	// refused with 401.
-	noMetricsToken
-	wrongAdminToken
 )
 
 // send sends r from the client at from, checks its answer and log line as
@@ -45,14 +40,6 @@ func (r refused) send(s *sender, from string) logLine {
 			requestlog.ActionRuleBlocked)
 	case banRule:
 		return s.request(from, probePath, http.StatusForbidden, requestlog.ActionBanned)
-	case noMetricsToken:
-		return s.request(from, proxy.MetricsPath, http.StatusUnauthorized,
-			requestlog.ActionAdmin)
-	case wrongAdminToken:
-		line, _ := s.requestWithHeader(from, proxy.BansPath, "Authorization: "+bearer,
-			http.StatusUnauthorized, requestlog.ActionAdmin)
-
-		return line
 	}
 
 	s.t.Fatalf("no request for the refusal %d", r)
@@ -60,17 +47,16 @@ func (r refused) send(s *sender, from string) logLine {
 	return logLine{}
 }
 
-// startForErrorBurst is startWithClock with testRules, both tokens and
+// startForErrorBurst is startWithClock with testRules, the metrics token and
 // SWWAF_ERROR_BURST_THRESHOLD at threshold, and the settings in env.
 func startForErrorBurst(
 	t *testing.T, threshold string, env map[string]string,
-) (*sender, *clock, *proxy.Server) {
+) (*sender, *clock, *servewaf.Server) {
 	t.Helper()
 
 	settings := map[string]string{
 		errorBurstThreshold: threshold,
 		rulesDir:            writeRules(t, testRules),
-		adminToken:          adminSecret,
 		metricsToken:        token,
 	}
 	maps.Copy(settings, env)
@@ -87,14 +73,7 @@ func TestErrorBurstBreaksAtOneOverTheThreshold(t *testing.T) {
 		refusals []refused
 	}{
 		{"block rule", []refused{blockRule, blockRule, blockRule, blockRule}},
-		{
-			"missing or wrong token",
-			[]refused{noMetricsToken, wrongAdminToken, noMetricsToken, wrongAdminToken},
-		},
-		{
-			"a mix ending in a ban rule",
-			[]refused{blockRule, noMetricsToken, blockRule, banRule},
-		},
+		{"a ban rule last", []refused{blockRule, blockRule, blockRule, banRule}},
 	} {
 		t.Run(tc.name, func(t *testing.T) {
 			t.Parallel()
@@ -127,16 +106,33 @@ func TestErrorBurstBreaksAtOneOverTheThreshold(t *testing.T) {
 	}
 }
 
-func TestErrorBurstBanNotesHistoryAndMetrics(t *testing.T) {
+func TestRefusalLimitBanNamesItsHeuristicWindowCountAndLimit(t *testing.T) {
 	t.Parallel()
 
-	const scraper = "192.0.2.200"
+	s, _, _ := startForErrorBurst(t, "1", nil)
+
+	const ruleFigures = `{"rule_id": "blocked", "rule_action": "block"}`
+
+	line := blockRule.send(s, client)
+	wantHeuristic(t, line, "rule_files", ruleFigures)
+	wantAfterAnswerHeuristic(t, line, "", "null")
+
+	// The second refusal is the request refusal_limit bans for, and the line
+	// names both.
+	line = blockRule.send(s, client)
+	wantHeuristic(t, line, "rule_files", ruleFigures)
+	wantAfterAnswerHeuristic(t, line, "refusal_limit",
+		`{"window": "minute", "count": 2, "limit": 1}`)
+}
+
+func TestErrorBurstBanNotesHistoryAndMetrics(t *testing.T) {
+	t.Parallel()
 
 	s, clk, server := startForErrorBurst(t, "2", nil)
 	start := clk.Now()
 
 	blockRule.send(s, client)
-	wrongAdminToken.send(s, client)
+	blockRule.send(s, client)
 	line := blockRule.send(s, client)
 
 	expires := start.Add(time.Hour)
@@ -173,19 +169,17 @@ func TestErrorBurstBanNotesHistoryAndMetrics(t *testing.T) {
 		t.Fatalf("bans\n%+v\nwant\n%+v", got, want)
 	}
 
-	wantOffences := ratelimit.Offences{Limit: 1, RuleBlocked: 2, TokenRefused: 1}
+	wantOffences := ratelimit.Offences{Limit: 1, RuleBlocked: 3}
 	if offences := historyOf(t, server, client).Offences; offences != wantOffences {
 		t.Errorf("history counts the offences %+v, want %+v", offences, wantOffences)
 	}
 
-	metrics := s.scrape(scraper)
+	metrics := s.scrape()
 	wantMetric(t, metrics, `smallwebwaf_rate_limit_hits_total{instance="app",`+
 		`kind="refusals",window="minute"}`, 1)
 	wantMetric(t, metrics, `smallwebwaf_offences_total{instance="app",kind="limit"}`, 1)
 	wantMetric(t, metrics,
-		`smallwebwaf_offences_total{instance="app",kind="rule_blocked"}`, 2)
-	wantMetric(t, metrics,
-		`smallwebwaf_offences_total{instance="app",kind="token_refused"}`, 1)
+		`smallwebwaf_offences_total{instance="app",kind="rule_blocked"}`, 3)
 	wantMetric(t, metrics, `smallwebwaf_bans_made_total{cause="limit",instance="app"}`, 1)
 }
 
@@ -291,19 +285,15 @@ func TestErrorBurstCountsEachClientTheChecksApplyTo(t *testing.T) {
 		allowNets: allowed, rateLimitExemptNets: exempt,
 	})
 
-	// A client in SWWAF_ALLOW_NETS still needs the token, but is not
-	// counted.
+	// A client in SWWAF_ALLOW_NETS is not refused, and so not counted.
 	for range 3 {
-		line := noMetricsToken.send(s, allowed)
-		if line.LimitHit != "" {
-			t.Errorf("log line has limit_hit %q, want none", line.LimitHit)
-		}
+		s.request(allowed, blockedPath, http.StatusOK, requestlog.ActionForward)
 	}
 
 	// One the rate limits do not apply to is.
-	noMetricsToken.send(s, exempt)
+	blockRule.send(s, exempt)
 
-	line := wrongAdminToken.send(s, exempt)
+	line := blockRule.send(s, exempt)
 	if line.LimitHit != requestlog.LimitHitErrorBurst {
 		t.Errorf("log line has limit_hit %q, want error_burst", line.LimitHit)
 	}
@@ -336,7 +326,6 @@ func TestObserveModeLogsAndAlertsTheErrorBurst(t *testing.T) {
 		mode:                observe,
 		errorBurstThreshold: "1",
 		rulesDir:            writeRules(t, testRules),
-		adminToken:          adminSecret,
 	})
 	start := clk.Now()
 	held := bans.Ban{
@@ -347,10 +336,11 @@ func TestObserveModeLogsAndAlertsTheErrorBurst(t *testing.T) {
 	}
 	server.Ledger.Load([]bans.Ban{held})
 
-	// Under a ban, enforce mode would have refused these before the
-	// endpoint, so their tokens are not counted.
+	// Under a ban, enforce mode would have refused these before the rule, so
+	// they are not counted.
 	for range 2 {
-		line := wrongAdminToken.send(s, otherClient)
+		line := s.request(otherClient, blockedPath, http.StatusOK,
+			requestlog.ActionForward)
 		wantWouldAction(t, line, requestlog.ActionBanned)
 
 		if line.LimitHit != "" {
@@ -360,7 +350,7 @@ func TestObserveModeLogsAndAlertsTheErrorBurst(t *testing.T) {
 
 	// The block rule's refusal, which enforce mode would have answered 403,
 	// is the second of the client's, and would have banned it.
-	wrongAdminToken.send(s, client)
+	s.request(client, blockedPath, http.StatusOK, requestlog.ActionForward)
 
 	line := s.request(client, blockedPath, http.StatusOK, requestlog.ActionForward)
 	wantWouldAction(t, line, requestlog.ActionRuleBlocked)

internal/servewaf/reputation.go

@@ -0,0 +1,48 @@
+package servewaf
+
+// What the reputation heuristics share: blocklists, crowdsec, dnsbl and
+// abuseipdb.
+
+import (
+	"sneak.berlin/go/smallwebwaf/internal/alerts"
+	"sneak.berlin/go/smallwebwaf/internal/bans"
+)
+
+// deny is the SWWAF_BLOCKLIST_ACTION and the SWWAF_REPUTATION_ACTION that
+// refuses the requests of a client a source lists.
+const deny = "deny"
+
+// noteListed notes each of sources, the URLs of the blocklists or the
+// DNSBL zones, their keys masked, that list the client, as noteHit does,
+// with reason.
+func (rq *request) noteListed(sources []string, reason string) {
+	for _, source := range sources {
+		rq.noteHit(bans.ReputationHit{Source: source}, reason)
+	}
+}
+
+// noteHit adds hit's source, which lists the client, to the log line's
+// reputation, and hit to the notes of a ban the request makes, counts the
+// source in the metrics, and raises a reputation_hit alert with reason,
+// whose detail gives hit's source and score.
+func (rq *request) noteHit(hit bans.ReputationHit, reason string) {
+	detail := map[string]any{"source": hit.Source}
+	if hit.Score != nil {
+		detail["score"] = *hit.Score
+	}
+
+	rq.line.Reputation = append(rq.line.Reputation, hit.Source)
+	rq.reputation = append(rq.reputation, hit)
+	rq.h.metrics.ReputationHit(hit.Source)
+	rq.h.alerts.Raise(alerts.Alert{
+		Event:    alerts.EventReputationHit,
+		Host:     rq.site,
+		Client:   rq.client,
+		Netblock: rq.h.clientGroup(rq.client),
+		ASN:      rq.line.ASN,
+		ASName:   rq.line.ASName,
+		Country:  rq.line.Country,
+		Reason:   reason,
+		Detail:   detail,
+	})
+}

internal/servewaf/reputation_test.go

@@ -1,4 +1,4 @@
-package proxy_test
+package servewaf_test
 
 import (
 	"fmt"
@@ -15,10 +15,10 @@ import (
 
 	"sneak.berlin/go/smallwebwaf/internal/alerts"
 	"sneak.berlin/go/smallwebwaf/internal/bans"
-	"sneak.berlin/go/smallwebwaf/internal/proxy"
 	"sneak.berlin/go/smallwebwaf/internal/ratelimit"
 	"sneak.berlin/go/smallwebwaf/internal/reputation"
 	"sneak.berlin/go/smallwebwaf/internal/requestlog"
+	"sneak.berlin/go/smallwebwaf/internal/servewaf"
 )
 
 // The reputation settings.
@@ -118,6 +118,56 @@ func TestEachBlocklistActionForAListedAddressAndAListedNetblock(t *testing.T) {
 	}
 }
 
+func TestReputationRefusalNamesItsHeuristicAndWhatListedTheClient(t *testing.T) {
+	t.Parallel()
+
+	for _, tc := range []struct {
+		heuristic string
+		env       map[string]string
+		load      func(*testing.T, *servewaf.Server)
+		figures   string
+	}{
+		{
+			"blocklists",
+			map[string]string{blocklistURLs: dropURL, blocklistAction: actionDeny},
+			func(t *testing.T, server *servewaf.Server) {
+				t.Helper()
+				loadLists(t, server, map[string][]string{dropURL: {client}})
+			},
+			`{"lists": ["` + dropURL + `"]}`,
+		},
+		{
+			"dnsbl",
+			map[string]string{
+				dnsblZones: dnsblZone, dnsblResolver: noResolver,
+				reputationAction: actionDeny,
+			},
+			func(_ *testing.T, server *servewaf.Server) {
+				loadVerdicts(server, map[string][]string{client: {dnsblZone}})
+			},
+			`{"zones": ["` + dnsblZone + `"]}`,
+		},
+		{
+			"abuseipdb",
+			map[string]string{abuseIPDBKey: accountKey, reputationAction: actionDeny},
+			func(_ *testing.T, server *servewaf.Server) {
+				loadScores(server, map[string]int64{client: 80})
+			},
+			`{"score": 80, "min_score": 75}`,
+		},
+	} {
+		t.Run(tc.heuristic, func(t *testing.T) {
+			t.Parallel()
+
+			s, server, _ := startWithLookups(t, tc.env)
+			tc.load(t, server)
+
+			line := s.get(client, http.StatusForbidden, requestlog.ActionDenied)
+			wantHeuristic(t, line, tc.heuristic, tc.figures)
+		})
+	}
+}
+
 func TestBlocklistsComeAfterTheCountryListsAndSkipAllowNets(t *testing.T) {
 	t.Parallel()
 
@@ -272,6 +322,7 @@ func TestEachBlocklistThatListsAClientRaisesAnAlertOncePerCooldownAndIsCounted(
 			Instance: alertInstance,
 			Time:     clk.Now(),
 			Event:    alerts.EventReputationHit,
+			Host:     appHost,
 			Client:   netip.MustParseAddr(fromDE),
 			Netblock: netip.MustParsePrefix(fromDE + "/32"),
 			ASN:      asnDE,
@@ -289,7 +340,7 @@ func TestEachBlocklistThatListsAClientRaisesAnAlertOncePerCooldownAndIsCounted(
 
 	// Each list's hits, none of its fetches failed, and when its copy was
 	// fetched, 0 for the one without.
-	metrics := s.scrape(unplaced)
+	metrics := s.scrape()
 	fetched := float64(listsFetched().Unix())
 
 	for listURL, want := range map[string]struct{ hits, fetched float64 }{
@@ -513,6 +564,7 @@ func TestEachZoneThatListsAClientRaisesAnAlertOncePerCooldownAndIsCounted(
 			Instance: alertInstance,
 			Time:     clk.Now(),
 			Event:    alerts.EventReputationHit,
+			Host:     appHost,
 			Client:   netip.MustParseAddr(fromDE),
 			Netblock: netip.MustParsePrefix(fromDE + "/32"),
 			ASN:      asnDE,
@@ -530,7 +582,7 @@ func TestEachZoneThatListsAClientRaisesAnAlertOncePerCooldownAndIsCounted(
 
 	// Each zone's hits, and its queries and their failures, none, since
 	// every client had its verdicts.
-	metrics := s.scrape(unplaced)
+	metrics := s.scrape()
 
 	for _, zone := range []string{dnsblZone, otherZone} {
 		labels := `{instance="` + alertInstance + `",source="` + zone + `"}`
@@ -564,7 +616,7 @@ func TestZoneKeyIsMaskedInTheLogTheAlertAndTheMetrics(t *testing.T) {
 			masked)
 	}
 
-	metrics := s.scrape(unplaced)
+	metrics := s.scrape()
 	wantMetric(t, metrics, `smallwebwaf_reputation_hits_total{instance="`+
 		alertInstance+`",source="`+masked+`"}`, 1)
 
@@ -615,7 +667,7 @@ const (
 // AbuseIPDB.
 const abuseipdb = reputation.AbuseIPDBSource
 
-// abuseIPDBURL is where newProxy has clients checked with AbuseIPDB: at
+// abuseIPDBURL is where newServeWAF has clients checked with AbuseIPDB: at
 // abuseIPDBStandIn, which TestMain registers with Go's default transport,
 // through which AbuseIPDB is asked.
 const abuseIPDBURL = "abuseipdb://stand-in/api/v2/check"
@@ -737,10 +789,6 @@ func TestClientRefusedForAnOffenceIsCheckedWithAbuseIPDBAtItsNextRequest(t *test
 			"a trap path", "/xmlrpc.php", http.StatusForbidden, requestlog.ActionBanned,
 			ratelimit.Offences{Attack: 1},
 		},
-		{
-			"a missing token", proxy.MetricsPath, http.StatusUnauthorized,
-			requestlog.ActionAdmin, ratelimit.Offences{TokenRefused: 1},
-		},
 	} {
 		t.Run(tc.name, func(t *testing.T) {
 			t.Parallel()
@@ -748,7 +796,7 @@ func TestClientRefusedForAnOffenceIsCheckedWithAbuseIPDBAtItsNextRequest(t *test
 			s, clk, server := startWithClock(t, "", map[string]string{
 				abuseIPDBKey: accountKey, reputationAction: actionLog,
 				rulesDir: writeRules(t, testRules), attackBanDuration: "1h",
-				trapPaths: trapPathList, metricsToken: token, wafMode: block,
+				trapPaths: trapPathList, wafMode: block,
 			})
 
 			s.request(client, tc.path, tc.status, tc.action)
@@ -862,7 +910,7 @@ func TestAbuseIPDBHitRaisesAnAlertWithTheScoreOncePerCooldownAndIsCounted(
 
 	// The hits, and the checks, none, since no client committed an
 	// offence, so that the whole budget is left.
-	metrics := s.scrape(unplaced)
+	metrics := s.scrape()
 	labels := `{instance="` + alertInstance + `",source="` + abuseipdb + `"}`
 
 	wantMetric(t, metrics, "smallwebwaf_reputation_hits_total"+labels, 2)
@@ -889,7 +937,7 @@ func TestWithoutAnAbuseIPDBKeyNoClientIsCheckedNorAScoreUsed(t *testing.T) {
 	wantReputation(t, s.get(fromDE, http.StatusOK, forward))
 	wantAbuseIPDBChecks(t, server, 0)
 
-	wantNoSeries(t, s.scrape(unplaced), `smallwebwaf_reputation_daily_budget_remaining{`+
+	wantNoSeries(t, s.scrape(), `smallwebwaf_reputation_daily_budget_remaining{`+
 		`instance="`+alertInstance+`",source="`+abuseipdb+`"}`)
 }
 
@@ -977,7 +1025,7 @@ func verdictsFetched() time.Time {
 // verdictsFetched, as reputation.json would at start: one that lists the
 // client from each zone listedBy gives for it, and one that does not from
 // each other zone.
-func loadVerdicts(server *proxy.Server, listedBy map[string][]string) {
+func loadVerdicts(server *servewaf.Server, listedBy map[string][]string) {
 	verdicts := make([]reputation.Verdict, 0, len(listedBy)*len(server.DNSBL.Zones()))
 
 	for client, zones := range listedBy {
@@ -995,7 +1043,7 @@ func loadVerdicts(server *proxy.Server, listedBy map[string][]string) {
 // loadScores puts into server's AbuseIPDB the score scores gives each
 // client, an IPv4 address, fetched at verdictsFetched, as reputation.json
 // would at start.
-func loadScores(server *proxy.Server, scores map[string]int64) {
+func loadScores(server *servewaf.Server, scores map[string]int64) {
 	kept := make([]reputation.Score, 0, len(scores))
 	for client, score := range scores {
 		kept = append(kept, reputation.Score{
@@ -1009,7 +1057,7 @@ func loadScores(server *proxy.Server, scores map[string]int64) {
 
 // wantAbuseIPDBChecks checks how many clients server has checked with
 // AbuseIPDB.
-func wantAbuseIPDBChecks(t *testing.T, server *proxy.Server, want int) {
+func wantAbuseIPDBChecks(t *testing.T, server *servewaf.Server, want int) {
 	t.Helper()
 
 	if got := server.AbuseIPDB.Checked(); got != want {
@@ -1019,7 +1067,7 @@ func wantAbuseIPDBChecks(t *testing.T, server *proxy.Server, want int) {
 
 // loadLists puts copies of lists into server's lists, by URL, each with
 // its lines, fetched at listsFetched, as reputation.json would at start.
-func loadLists(t *testing.T, server *proxy.Server, copies map[string][]string) {
+func loadLists(t *testing.T, server *servewaf.Server, copies map[string][]string) {
 	t.Helper()
 
 	lists := make([]reputation.List, 0, len(copies))

internal/servewaf/request.go

@@ -0,0 +1,400 @@
+package servewaf
+
+import (
+	"context"
+	"net/http"
+	"net/netip"
+	"slices"
+	"strings"
+	"time"
+
+	"sneak.berlin/go/smallwebwaf/internal/anomaly"
+	"sneak.berlin/go/smallwebwaf/internal/bans"
+	"sneak.berlin/go/smallwebwaf/internal/config"
+	"sneak.berlin/go/smallwebwaf/internal/lookup"
+	"sneak.berlin/go/smallwebwaf/internal/ratelimit"
+	"sneak.berlin/go/smallwebwaf/internal/requestlog"
+	"sneak.berlin/go/smallwebwaf/internal/rules"
+)
+
+// refusal is servewaf refusing a request: the status the visitor is to get, 0
+// to close its connection without an answer, and the action the log line names.
+type refusal struct {
+	status int
+	action string
+}
+
+// decision is what the checks note of a request: its log line, and what
+// counting the request needs once it has ended. servewaf keeps a copy of it
+// until the request's report comes. It holds no credentials, since the log line
+// never does, and neither the request's objects nor their bodies.
+type decision struct {
+	line   requestlog.Line
+	client netip.Addr
+	// requestURI is the path with the query, as a ban's notes keep it.
+	requestURI string
+	// site is, for a question, the host the visitor asked for, which the
+	// alerts name, since one servewaf serves many sites.
+	site string
+	// allowed is true for a question answered with DispositionAllow.
+	allowed bool
+	// lookedUp is true once the client's AS number and country have been
+	// looked up, whether or not an answer was there, and lookupAnswer is
+	// what the lookup gave then, the zero Answer while GeoJS had given none.
+	lookedUp     bool
+	lookupAnswer lookup.Answer
+	// skippedLookupWait is true for a request that did not wait for GeoJS and
+	// found no answer kept. SWWAF_UNKNOWN_LIMIT_PERCENT does not apply to it,
+	// so that not waiting never lowers its client's limits.
+	skippedLookupWait bool
+	// counted is true for a request the rate limits counted, whose bytes
+	// the byte limits count once it has ended. limitPercent and
+	// bytesPercent are then its client's limit percentages for the rate
+	// limits and for the byte limits.
+	counted                    bool
+	limitPercent, bytesPercent percentage
+	// attack is true for a request that matched a ban rule or asked for a
+	// trap path, ruleBlocked for one a block rule refused, and wafBlocked for
+	// one the Core Rule Set refused, each an offence its client's history
+	// counts.
+	attack, ruleBlocked, wafBlocked bool
+	// reputation is the reputation sources that list the client, for the
+	// notes of a ban the request makes.
+	reputation []bans.ReputationHit
+}
+
+// request is one request to servewaf, from the moment its headers have been
+// read to its log line.
+type request struct {
+	decision
+
+	h   *handler
+	in  *http.Request
+	out *responseWriter
+
+	// blocklisted is true once a blocklist is found to list the client,
+	// dnsblListed once a DNSBL zone's verdict is, and abuseIPDBHit once
+	// AbuseIPDB's score of it is a hit.
+	blocklisted, dnsblListed, abuseIPDBHit bool
+	start                                  time.Time
+	// checked is when the checks were done.
+	checked time.Time
+	// refused is what the request was refused with, nil if it was not.
+	refused *refusal
+	// requestBytes is how many bytes of the request's body have been read.
+	requestBytes int64
+}
+
+// startRequest starts handling r from client, which came through peer: it
+// notes the time, counts the request as under way, and starts the log line
+// with what is known of the request. isQuestion says whether r is a question,
+// whose headers give the request's id and scheme.
+func (h *handler) startRequest(
+	w http.ResponseWriter, r *http.Request, client, peer netip.Addr, isQuestion bool,
+) *request {
+	h.metrics.RequestStarted()
+
+	start := time.Now()
+	forwardedFor := r.Header.Values("X-Forwarded-For")
+
+	rq := &request{
+		decision: decision{
+			client:     client,
+			requestURI: r.URL.RequestURI(),
+			line: requestlog.Line{
+				Time:             requestlog.FormatTime(start),
+				Instance:         h.config.InstanceName,
+				ClientIP:         client.String(),
+				Method:           r.Method,
+				Scheme:           scheme(r, isQuestion),
+				Host:             r.Host,
+				Path:             rules.Path(r),
+				Query:            r.URL.RawQuery,
+				Protocol:         r.Proto,
+				Referer:          r.Referer(),
+				UserAgent:        r.UserAgent(),
+				RequestID:        requestID(r, isQuestion),
+				PeerIP:           peer.String(),
+				ForwardedFor:     strings.Join(forwardedFor, ", "),
+				ClientGroup:      h.clientGroup(client).String(),
+				ContentType:      r.Header.Get("Content-Type"),
+				RequestHeaders:   requestHeaders(r, h.config.LogRequestHeaders),
+				HasAuthorization: len(r.Header.Values("Authorization")) > 0,
+				HasCookie:        len(r.Header.Values("Cookie")) > 0,
+				Action:           requestlog.ActionForward,
+			},
+		},
+		h:     h,
+		in:    r,
+		out:   &responseWriter{ResponseWriter: w},
+		start: start,
+	}
+
+	// A length of -1 is a body whose length was not announced.
+	if r.ContentLength > 0 {
+		rq.line.ContentLength = r.ContentLength
+	}
+
+	return rq
+}
+
+// requestHeaders returns the headers of r that names lists, by name in
+// lower case, each with its values joined by ", ". Authorization, Cookie
+// and Set-Cookie are never among them, whatever names says.
+func requestHeaders(r *http.Request, names []string) map[string]string {
+	headers := map[string]string{}
+
+	for _, name := range names {
+		switch name {
+		case "authorization", "cookie", "set-cookie":
+			continue
+		}
+
+		values := r.Header.Values(name)
+		if len(values) > 0 {
+			headers[name] = strings.Join(values, ", ")
+		}
+	}
+
+	return headers
+}
+
+// check is the one place where a request can be refused. It returns nil to let
+// the request through. The heuristics of checkClient decide: a request they
+// refuse is answered with SWWAF_BAN_RESPONSE, 403 for a block rule or the Core
+// Rule Set, or 431 for the header limits. In observe mode nothing is refused,
+// and the log line names what enforce mode would have done. ctx is the
+// request's own context.
+func (rq *request) check(ctx context.Context) *refusal {
+	v := rq.checkClient(ctx)
+	if v == nil {
+		return nil
+	}
+
+	action := v.action
+
+	switch {
+	case rq.h.config.Observe:
+		rq.line.WouldAction = action
+
+		return nil
+	case action == requestlog.ActionRuleBlocked || action == requestlog.ActionWAFBlocked:
+		return &refusal{status: http.StatusForbidden, action: action}
+	case action == requestlog.ActionTooLarge:
+		return &refusal{status: http.StatusRequestHeaderFieldsTooLarge, action: action}
+	default:
+		return rq.banResponse(action)
+	}
+}
+
+// checkClient runs the heuristics of beforeLookup on the request, then looks
+// up the client's AS number and country, then runs those of afterLookup. It
+// returns the first verdict, or nil when none gives one. A client in
+// SWWAF_ALLOW_NETS skips them all, and is not looked up. ctx is the request's
+// own context.
+func (rq *request) checkClient(ctx context.Context) *verdict {
+	if isInside(rq.client, rq.h.config.AllowNets) {
+		return nil
+	}
+
+	now := rq.h.now()
+
+	v := rq.runHeuristics(ctx, beforeLookup(), now)
+	if v != nil {
+		return v
+	}
+
+	rq.lookUp(ctx, now)
+
+	// The lookup can wait for GeoJS, so the checks after it read the time
+	// again: a request counted at the time it arrived could be counted
+	// after a later one of its client's, which the rate limits would take
+	// for the clock set back.
+	return rq.runHeuristics(ctx, afterLookup(), rq.h.now())
+}
+
+// pathExempt reports whether r is exempt under prefixes,
+// SWWAF_RATE_LIMIT_EXEMPT_PATHS or SWWAF_WAF_EXEMPT_PATHS: whether its
+// path as sent, the path the app receives, not percent-decoded, starts
+// with one of prefixes, so that /%61ssets/x is not under /assets/ for an
+// app whose router matches the path as received. A request whose decoded
+// path contains .. anywhere or a backslash, or whose path as sent holds an
+// encoded slash (%2F or %2f), never is, since an app may act on it as a
+// path outside every prefix: /assets/..%2Flogin as /login, or /assets%2Fx
+// as one path segment, as Go's router does.
+func pathExempt(r *http.Request, prefixes []string) bool {
+	decoded := r.URL.Path
+	sent := rules.Path(r)
+
+	if strings.Contains(decoded, "..") || strings.Contains(decoded, `\`) ||
+		strings.Contains(strings.ToLower(sent), "%2f") {
+		return false
+	}
+
+	return slices.ContainsFunc(prefixes, func(prefix string) bool {
+		return strings.HasPrefix(sent, prefix)
+	})
+}
+
+// finish counts the request in the metrics and writes its log line.
+func (rq *request) finish() {
+	line := &rq.line
+	line.Status = rq.out.status
+	line.ResponseBytes = rq.out.bytes
+	line.ResponseContentType = rq.out.Header().Get("Content-Type")
+	line.RequestBytes = rq.requestBytes
+
+	switch {
+	case rq.refused != nil:
+		line.Action = rq.refused.action
+	case rq.out.err != nil || rq.in.Context().Err() != nil:
+		line.Aborted = true
+	}
+
+	duration := time.Since(rq.start)
+	line.DurationTotal = requestlog.Milliseconds(duration)
+	line.DurationChecks = timing(rq.start, rq.checked)
+
+	// Counted before the log line is written, so that the metrics count
+	// every request whose line is out. An allowed request is the exception:
+	// its report gives the status, bytes and times the metrics count.
+	if rq.allowed {
+		rq.h.metrics.RequestAllowed()
+	} else {
+		rq.h.metrics.RequestEnded(line, duration)
+	}
+
+	rq.writeLine()
+}
+
+// writeLine writes the request's log line.
+func (rq *request) writeLine() {
+	err := requestlog.Write(rq.h.requestLog, &rq.line)
+	if err != nil {
+		rq.h.processLog.Error("writing the request log failed", "error", err.Error())
+	}
+}
+
+// timing is the time from start to end in milliseconds, for one of the
+// log line's timings, or nil when end is zero: what it times never
+// happened.
+func timing(start, end time.Time) *float64 {
+	if end.IsZero() {
+		return nil
+	}
+
+	return new(requestlog.Milliseconds(end.Sub(start)))
+}
+
+// addToHistory adds the request, which has ended, to its client's
+// history, and counts its offences in the metrics, and then the lookup's
+// answer about the client, as answerAtTheEnd gives it, to that history and
+// to the notes of the bans on its netblock: an answer may have come
+// before either was there, and one from GeoJS that comes later is added
+// when it comes.
+func (rq *request) addToHistory() {
+	request := ratelimit.Request{
+		Forwarded:     rq.allowed,
+		Refused:       rq.refused != nil,
+		Status:        rq.out.status,
+		RequestBytes:  rq.requestBytes,
+		ResponseBytes: rq.out.bytes,
+		BrokeLimit:    rq.line.Offence == requestlog.OffenceLimit,
+		Attack:        rq.attack,
+		RuleBlocked:   rq.ruleBlocked,
+		WAFBlocked:    rq.wafBlocked,
+	}
+
+	rq.h.limiter.AddToHistory(rq.h.clientGroup(rq.client), rq.h.now(), request)
+	rq.h.metrics.Offences(request)
+
+	answer, found := rq.answerAtTheEnd()
+	if found {
+		rq.h.addLookup(answer)
+	}
+}
+
+// countAnomalies counts the request, which has ended, and its bytes, as
+// countedBytes gives them, for the anomaly thresholds, whatever was done
+// with it: a request refused, one from a client in SWWAF_ALLOW_NETS or
+// SWWAF_RATE_LIMIT_EXEMPT_NETS, and one for a path in
+// SWWAF_RATE_LIMIT_EXEMPT_PATHS are counted too. It is counted for its
+// client's AS number when answerAtTheEnd gives one. With every anomaly
+// threshold off, the default, it does nothing.
+func (rq *request) countAnomalies() {
+	if !anomalyThresholdsSet(rq.h.config) {
+		return
+	}
+
+	answer, _ := rq.answerAtTheEnd()
+
+	rq.h.anomalies.Count(rq.h.now(), anomaly.Request{
+		Host:        rq.site,
+		Client:      rq.client,
+		ClientGroup: rq.h.clientGroup(rq.client),
+		ASN:         answer.ASN,
+		ASName:      answer.ASName,
+		Country:     answer.Country,
+		Bytes:       rq.countedBytes(),
+	})
+}
+
+// anomalyThresholdsSet reports whether any anomaly threshold is set.
+func anomalyThresholdsSet(cfg *config.Config) bool {
+	off := anomaly.Thresholds{}
+
+	return cfg.AnomalyClient != off || cfg.AnomalyNet != off || cfg.AnomalyASN != off ||
+		cfg.AnomalyTotal != off || cfg.AnomalyWatch != off
+}
+
+// answerAtTheEnd returns, for a client that was looked up, the lookup's
+// answer about it as the request ends, and whether there is one: the
+// lookup database's, which was there at once, or the one GeoJS has given
+// by then, which a request does not wait for unless a setting needs it.
+func (rq *request) answerAtTheEnd() (lookup.Answer, bool) {
+	if !rq.lookedUp {
+		return lookup.Answer{}, false
+	}
+
+	if rq.h.config.LookupSource == "file" {
+		return rq.lookupAnswer, true
+	}
+
+	return rq.h.geojs.Kept(rq.h.clientGroup(rq.client))
+}
+
+// responseWriter is servewaf's answer to a request. It notes the status and
+// size for the log line, and the first error writing the answer.
+type responseWriter struct {
+	http.ResponseWriter
+
+	// status is the status sent, or zero before one is.
+	status int
+	bytes  int64
+	err    error
+}
+
+// WriteHeader sends the status and headers.
+func (w *responseWriter) WriteHeader(status int) {
+	if w.status == 0 {
+		w.status = status
+	}
+
+	w.ResponseWriter.WriteHeader(status)
+}
+
+// Write sends part of the body.
+func (w *responseWriter) Write(p []byte) (int, error) {
+	if w.status == 0 {
+		w.status = http.StatusOK
+	}
+
+	n, err := w.ResponseWriter.Write(p)
+	w.bytes += int64(n)
+
+	if w.err == nil {
+		w.err = err
+	}
+
+	return n, err
+}

internal/servewaf/requestlog_test.go

@@ -1,8 +1,8 @@
-package proxy_test
+package servewaf_test
 
 import (
+	"encoding/json"
 	"io"
-	"maps"
 	"math"
 	"net/http"
 	"reflect"
@@ -11,9 +11,9 @@ import (
 	"testing"
 	"time"
 
-	"sneak.berlin/go/smallwebwaf/internal/proxy"
 	"sneak.berlin/go/smallwebwaf/internal/ratelimit"
 	"sneak.berlin/go/smallwebwaf/internal/requestlog"
+	"sneak.berlin/go/smallwebwaf/internal/servewaf"
 )
 
 const (
@@ -42,9 +42,6 @@ func TestLogLineHasEachFieldWhereItApplies(t *testing.T) {
 			return
 		}
 
-		w.Header().Set("Content-Type", "text/html")
-		w.Header().Set("Cache-Control", "no-store")
-		w.Header().Set("Location", "/elsewhere")
 		w.WriteHeader(http.StatusFound)
 		_, _ = io.WriteString(w, "moved")
 	})
@@ -70,7 +67,7 @@ func TestLogLineHasEachFieldWhereItApplies(t *testing.T) {
 
 	// A request's log line can come after its answer: each is waited for
 	// before the next request, so that the lines are in order.
-	full := out.requestLines(t, 1)[0]
+	full := out.endedLines(t, 1)[0]
 
 	// This one comes from 127.0.0.1, which the rate limits do not count,
 	// with a body of 4 bytes whose length it does not announce, so that its
@@ -81,7 +78,7 @@ func TestLogLineHasEachFieldWhereItApplies(t *testing.T) {
 		"Transfer-Encoding: chunked\r\n\r\n4\r\nbody\r\n0\r\n\r\n")
 	wantStatus(t, readResponse(t, conn), http.StatusNoContent)
 
-	bare := out.requestLines(t, 2)[1]
+	bare := out.endedLines(t, 2)[1]
 
 	wantFullLine(t, full)
 	wantBareLine(t, bare)
@@ -108,24 +105,23 @@ func wantFullLine(t *testing.T, line logLine) {
 	headers := map[string]string{"accept": "text/html", "x-custom": "one, two"}
 
 	want := withTimings(line, requestlog.Line{
-		Type: requestType, Time: line.Time, Instance: instance,
+		Type: requestType, ServeWAFLine: requestlog.ServeWAFLineReport,
+		Time: line.Time, Instance: instance,
 		ClientIP: ipv6Client, Method: http.MethodPost, Scheme: secure,
 		Host: appHost, Path: "/full", Protocol: protocol,
 		Status: http.StatusFound, RequestBytes: 3, ResponseBytes: 5,
-		RequestID: "from-traefik", PeerIP: localhost,
+		RequestID: line.RequestID, PeerIP: localhost,
 		ForwardedFor: "198.51.100.7, " + ipv6Client, ClientGroup: ipv6Group,
 		ContentType: "application/x-www-form-urlencoded", ContentLength: 3,
 		RequestHeaders: headers, HasAuthorization: true, HasCookie: true,
-		ResponseContentType: "text/html", UpstreamStatus: http.StatusFound,
-		CacheControl: "no-store", Location: "/elsewhere",
 		Action: requestlog.ActionForward,
 		// Its 3 bytes in and 5 out, each way counted by default.
 		Counts: ratelimit.Counts{
 			Minute: 1, Hour: 1, Day: 1, MinuteBytes: 8, HourBytes: 8, DayBytes: 8,
 		},
 	})
-	if !reflect.DeepEqual(line.Line, want) {
-		t.Errorf("log line\n%+v\nwant\n%+v", line.Line, want)
+	if !reflect.DeepEqual(line.Line, want) || line.RequestID == "from-traefik" {
+		t.Errorf("log line\n%+v\nwant\n%+v, with a new request id", line.Line, want)
 	}
 }
 
@@ -135,12 +131,13 @@ func wantBareLine(t *testing.T, line logLine) {
 	t.Helper()
 
 	want := withTimings(line, requestlog.Line{
-		Type: requestType, Time: line.Time, Instance: instance,
+		Type: requestType, ServeWAFLine: requestlog.ServeWAFLineReport,
+		Time: line.Time, Instance: instance,
 		ClientIP: localhost, Method: http.MethodPost, Scheme: plain,
 		Host: appHost, Path: "/bare", Protocol: protocol,
 		Status: http.StatusNoContent, RequestBytes: 4, RequestID: line.RequestID,
 		PeerIP: localhost, ClientGroup: localhost + "/32",
-		UpstreamStatus: http.StatusNoContent, Action: requestlog.ActionForward,
+		Action: requestlog.ActionForward,
 	})
 	if !reflect.DeepEqual(line.Line, want) || line.RequestID == "" {
 		t.Errorf("log line\n%+v\nwant\n%+v, with a request id", line.Line, want)
@@ -148,8 +145,7 @@ func wantBareLine(t *testing.T, line logLine) {
 
 	for _, name := range []string{
 		"forwarded_for", "content_type", "content_length", "request_headers",
-		"has_authorization", "has_cookie", "websocket", "response_content_type",
-		"cache_control", "location", "counts",
+		"has_authorization", "has_cookie", "response_content_type", "counts",
 	} {
 		_, present := line.fields[name]
 		if present {
@@ -162,8 +158,6 @@ func wantBareLine(t *testing.T, line logLine) {
 func withTimings(line logLine, want requestlog.Line) requestlog.Line {
 	want.DurationTotal = line.DurationTotal
 	want.DurationChecks = line.DurationChecks
-	want.DurationUpstreamConnect = line.DurationUpstreamConnect
-	want.DurationUpstreamFirstByte = line.DurationUpstreamFirstByte
 	want.DurationUpstreamTotal = line.DurationUpstreamTotal
 
 	return want
@@ -188,7 +182,7 @@ func TestHasAuthorizationAndHasCookieEachComeFromTheirOwnHeader(t *testing.T) {
 			req.Header.Set(tc.header, "secret")
 			wantStatus(t, do(t, req), http.StatusOK)
 
-			line := out.requestLine(t)
+			line := out.endedLine(t)
 
 			_, otherPresent := line.fields[tc.other]
 			if line.fields[tc.field] != true || otherPresent {
@@ -199,81 +193,20 @@ func TestHasAuthorizationAndHasCookieEachComeFromTheirOwnHeader(t *testing.T) {
 	}
 }
 
-func TestRequestIDAndSchemeComeOnlyFromATrustedProxy(t *testing.T) {
-	t.Parallel()
-
-	const sentID = "from-traefik"
-
-	sent := http.Header{requestIDHeader: {sentID}, forwardedProto: {secure}}
-	trusted := map[string]string{trustedProxies: trustLocalhost}
-
-	for _, tc := range []struct {
-		name   string
-		env    map[string]string
-		header http.Header
-		// wantID is the request id logged, "" for a new one.
-		wantID, wantScheme string
-	}{
-		{"a trusted proxy's are kept", trusted, sent, sentID, secure},
-		{"without them, the id is new and the scheme http", trusted, nil, "", plain},
-		{"another peer's are replaced", nil, sent, "", plain},
-	} {
-		t.Run(tc.name, func(t *testing.T) {
-			t.Parallel()
-
-			received := make(chan string, 2)
-			app := startApp(t, func(_ http.ResponseWriter, r *http.Request) {
-				received <- r.Header.Get(requestIDHeader)
-			})
-			addr, out := startProxy(t, app.URL, tc.env)
-
-			// Two requests, so that two new ids can be told apart.
-			ids := make([]string, 0, 2)
-
-			for i := range 2 {
-				req := newRequest(t, http.MethodGet, addr, "/", http.NoBody)
-				maps.Copy(req.Header, tc.header)
-				wantStatus(t, do(t, req), http.StatusOK)
-
-				line := out.requestLines(t, i+1)[i]
-				ids = append(ids, line.RequestID)
-
-				got := <-received
-				if line.RequestID != got || line.Scheme != tc.wantScheme {
-					t.Errorf("log line has request_id %q and scheme %q, and the "+
-						"app received id %q; want the same id and scheme %q",
-						line.RequestID, line.Scheme, got, tc.wantScheme)
-				}
-			}
-
-			switch {
-			case tc.wantID != "" && (ids[0] != tc.wantID || ids[1] != tc.wantID):
-				t.Errorf("request ids %q, want %q", ids, tc.wantID)
-			case tc.wantID == "" && (slices.Contains(ids, sentID) ||
-				slices.Contains(ids, "") || ids[0] == ids[1]):
-				t.Errorf("request ids %q, want two new ones", ids)
-			}
-		})
-	}
-}
-
 func TestTimingsAreInOrder(t *testing.T) {
 	t.Parallel()
 
 	const denied = "192.0.2.50" // in SWWAF_DENY_NETS
 
 	app := startApp(t, func(w http.ResponseWriter, _ *http.Request) {
-		// The pauses set the times apart; a hold-up of the test only
-		// lengthens them.
-		time.Sleep(time.Millisecond)
-		w.WriteHeader(http.StatusOK)
-		_ = http.NewResponseController(w).Flush()
-
+		// The pause sets the times apart; a hold-up of the test only lengthens
+		// it.
 		time.Sleep(time.Millisecond)
 
 		_, _ = io.WriteString(w, "done")
 	})
-	addr, out := startProxy(t, app.URL, map[string]string{
+
+	addr, out, server := startProxyWithClock(t, app.URL, "", time.Now, map[string]string{
 		trustedProxies: trustLocalhost,
 		denyNets:       denied,
 	})
@@ -281,20 +214,19 @@ func TestTimingsAreInOrder(t *testing.T) {
 	// Each log line is waited for before the next request, so that the
 	// lines are in order.
 	wantStatus(t, get(t, addr, "/"), http.StatusOK)
-	forwarded := out.requestLines(t, 1)[0]
+	forwarded := out.endedLines(t, 1)[0]
 
 	req := newRequest(t, http.MethodGet, addr, "/", http.NoBody)
 	req.Header.Set(forwardedFor, denied)
 	wantStatus(t, do(t, req), http.StatusForbidden)
-	refused := out.requestLines(t, 2)[1]
+	refused := out.endedLines(t, 2)[1]
 
-	wantStatus(t, get(t, addr, proxy.HealthPath), http.StatusOK)
-	health := out.requestLines(t, 3)[2]
+	wantStatus(t, get(t, server.Addr, servewaf.HealthPath), http.StatusOK)
+	health := out.endedLines(t, 3)[2]
 
 	// A request passed to the app has every timing; one refused, none of
 	// the app's; the health check, which runs no check, only the total.
 	wantTimings(t, forwarded, "duration_total", "duration_checks",
-		"duration_upstream_connect", "duration_upstream_first_byte",
 		"duration_upstream_total")
 	wantTimings(t, refused, "duration_total", "duration_checks")
 	wantTimings(t, health, "duration_total")
@@ -307,17 +239,12 @@ func TestTimingsAreInOrder(t *testing.T) {
 	// exact.
 	total := microseconds(forwarded.DurationTotal)
 	checks := microseconds(*forwarded.DurationChecks)
-	connect := microseconds(*forwarded.DurationUpstreamConnect)
-	firstByte := microseconds(*forwarded.DurationUpstreamFirstByte)
 	upstream := microseconds(*forwarded.DurationUpstreamTotal)
 
-	// The checks end before the request is handed to the app, and the
-	// connection comes before the answer, which the app ends after a
-	// pause.
-	if checks+upstream > total || connect >= firstByte || firstByte >= upstream {
-		t.Errorf("timings in microseconds: total %d, checks %d, connect %d, "+
-			"first byte %d, upstream total %d", total, checks, connect, firstByte,
-			upstream)
+	// The checks end before the request is handed to the app.
+	if checks+upstream > total {
+		t.Errorf("timings in microseconds: total %d, checks %d, upstream total %d",
+			total, checks, upstream)
 	}
 
 	if *refused.DurationChecks > refused.DurationTotal {
@@ -346,26 +273,49 @@ func wantTimings(t *testing.T, line logLine, want ...string) {
 	}
 }
 
+// wantHeuristic checks that line names heuristic as the one that refused the
+// request, with figures, a JSON object. A heuristic of "" with figures "null" is
+// a line that names none.
+func wantHeuristic(t *testing.T, line logLine, heuristic, figures string) {
+	t.Helper()
+
+	if line.Heuristic != heuristic ||
+		!reflect.DeepEqual(line.HeuristicFigures, decodeFigures(t, figures)) {
+		t.Errorf("log line has heuristic %q with heuristic_figures %v, want %q with %s",
+			line.Heuristic, line.HeuristicFigures, heuristic, figures)
+	}
+}
+
+// wantAfterAnswerHeuristic checks after_answer_heuristic and
+// after_answer_heuristic_figures as wantHeuristic checks heuristic and
+// heuristic_figures.
+func wantAfterAnswerHeuristic(t *testing.T, line logLine, heuristic, figures string) {
+	t.Helper()
+
+	if line.AfterAnswerHeuristic != heuristic ||
+		!reflect.DeepEqual(line.AfterAnswerHeuristicFigures, decodeFigures(t, figures)) {
+		t.Errorf("log line has after_answer_heuristic %q with "+
+			"after_answer_heuristic_figures %v, want %q with %s",
+			line.AfterAnswerHeuristic, line.AfterAnswerHeuristicFigures, heuristic, figures)
+	}
+}
+
+// decodeFigures decodes figures, a JSON object of a heuristic's figures, as
+// the log line's figures are decoded.
+func decodeFigures(t *testing.T, figures string) map[string]any {
+	t.Helper()
+
+	var decoded map[string]any
+
+	err := json.Unmarshal([]byte(figures), &decoded)
+	if err != nil {
+		t.Fatalf("decode %s: %v", figures, err)
+	}
+
+	return decoded
+}
+
 // microseconds is a timing in whole microseconds.
 func microseconds(milliseconds float64) int64 {
 	return int64(math.Round(milliseconds * 1000))
 }
-
-func TestLogsAnUpgradedConnection(t *testing.T) {
-	t.Parallel()
-
-	app := startApp(t, echoAfterUpgrade)
-	addr, out := startProxy(t, app.URL, nil)
-
-	conn := dial(t, addr)
-	send(t, conn, "GET /socket HTTP/1.1\r\nHost: app\r\n"+
-		"Connection: Upgrade\r\nUpgrade: websocket\r\n\r\n")
-	wantStatus(t, readResponse(t, conn), http.StatusSwitchingProtocols)
-
-	_ = conn.Close()
-
-	line := out.requestLine(t)
-	if line.fields["websocket"] != true {
-		t.Errorf("log line has websocket %v, want true", line.fields["websocket"])
-	}
-}

internal/servewaf/rulefiles.go

@@ -0,0 +1,55 @@
+package servewaf
+
+// The heuristic rule_files. It reads the rules of the rule files, which
+// SWWAF_RULES_DIR and SWWAF_RULES_ENABLED name.
+
+import (
+	"context"
+	"time"
+
+	"sneak.berlin/go/smallwebwaf/internal/bans"
+	"sneak.berlin/go/smallwebwaf/internal/requestlog"
+	"sneak.berlin/go/smallwebwaf/internal/rules"
+)
+
+// ruleFiles checks the request against the rules of the rule files at now,
+// notes the ids of those it matches in the log line, and refuses the request
+// when the last rule it matches refuses it: with ActionRuleBlocked for a block
+// rule, and ActionBanned for a ban rule. A ban rule bans the client's netblock
+// for a clear sign of attack, or in observe mode raises the alert for the ban
+// it would have made. Either rule's match is noted as an offence, for the
+// client's history. Its figures are the rule's id and action.
+type ruleFiles struct{}
+
+func (ruleFiles) name() string { return "rule_files" }
+
+func (ruleFiles) check(_ context.Context, rq *request, now time.Time) *verdict {
+	matched := rq.h.rules.Match(rq.in)
+
+	for _, rule := range matched {
+		rq.line.RuleIDs = append(rq.line.RuleIDs, rule.ID)
+		rq.h.metrics.RuleMatched(rule.ID, rule.Action)
+	}
+
+	if len(matched) == 0 {
+		return nil
+	}
+
+	// Only the last rule matched can refuse the request.
+	last := matched[len(matched)-1]
+	figures := map[string]any{"rule_id": last.ID, "rule_action": last.Action}
+
+	switch last.Action {
+	case rules.ActionBlock:
+		rq.ruleBlocked = true
+
+		return &verdict{action: requestlog.ActionRuleBlocked, figures: figures}
+	case rules.ActionBan:
+		rq.attack = true
+		rq.banForAttack(now, bans.Notes{RuleID: last.ID, Target: last.Target})
+
+		return &verdict{action: requestlog.ActionBanned, figures: figures}
+	default:
+		return nil
+	}
+}

internal/servewaf/rulefiles_test.go

@@ -1,4 +1,4 @@
-package proxy_test
+package servewaf_test
 
 import (
 	"net/http"
@@ -93,6 +93,21 @@ func TestEachRuleAction(t *testing.T) {
 	s.get(client, http.StatusTooManyRequests, requestlog.ActionBanned)
 }
 
+func TestRuleRefusalNamesItsHeuristicAndTheRule(t *testing.T) {
+	t.Parallel()
+
+	s, _, _ := startWithClock(t, "", map[string]string{
+		rulesDir: writeRules(t, "noted path log ^/\n"+testRules),
+	})
+
+	line := s.request(client, "/blocked", http.StatusForbidden,
+		requestlog.ActionRuleBlocked)
+	wantHeuristic(t, line, "rule_files", `{"rule_id": "blocked", "rule_action": "block"}`)
+
+	line = s.request(client, "/.env", http.StatusForbidden, requestlog.ActionBanned)
+	wantHeuristic(t, line, "rule_files", `{"rule_id": "probe", "rule_action": "ban"}`)
+}
+
 func TestNextClearSignOfAttackAfterABanBansPermanently(t *testing.T) {
 	t.Parallel()
 
@@ -185,8 +200,6 @@ func TestObserveModeLogsWhatTheRulesWouldDo(t *testing.T) {
 func TestMetricsCountRuleMatchesAndBansForAnAttack(t *testing.T) {
 	t.Parallel()
 
-	const scraper = "192.0.2.200"
-
 	s, _, _ := startWithClock(t, "", map[string]string{
 		rulesDir:     writeRules(t, testRules),
 		metricsToken: token,
@@ -196,7 +209,7 @@ func TestMetricsCountRuleMatchesAndBansForAnAttack(t *testing.T) {
 	s.request(client, "/.env", http.StatusForbidden, requestlog.ActionBanned)
 	s.get(client, http.StatusForbidden, requestlog.ActionBanned)
 
-	metrics := s.scrape(scraper)
+	metrics := s.scrape()
 	wantMetric(t, metrics,
 		`smallwebwaf_rule_matches_total{action="block",instance="app",rule_id="blocked"}`, 1)
 	wantMetric(t, metrics,

internal/servewaf/servewaf.go

@@ -1,11 +1,13 @@
-package proxy
+package servewaf
 
 import (
 	"bytes"
+	"context"
 	"encoding/json"
 	"errors"
 	"fmt"
 	"io"
+	"log/slog"
 	"net/http"
 	"net/netip"
 	"strconv"
@@ -13,8 +15,6 @@ import (
 	"time"
 	"unicode/utf8"
 
-	lru "github.com/hashicorp/golang-lru/v2"
-
 	"sneak.berlin/go/smallwebwaf/internal/requestlog"
 )
 
@@ -53,13 +53,6 @@ const ReportPath = "/_smallwebwaf/report"
 // QuestionBodyMaxBytes is the most of a visitor's body a question carries.
 const QuestionBodyMaxBytes = 64 << 10
 
-// The header limits: the most cookies and header fields a request may have
-// when the checks reach the Core Rule Set. Real clients never reach them.
-const (
-	maxCookies      = 50
-	maxHeaderFields = 100
-)
-
 const (
 	// maxAwaitingReport is the most answered requests held until their
 	// reports come. Past it, the request answered longest ago is dropped.
@@ -104,46 +97,39 @@ type Report struct {
 	DurationUpstreamTotal float64 `json:"duration_upstream_total"`
 }
 
-// NewServeWAF returns the server `smallwebwaf servewaf` runs. It answers
-// rproxy's questions with the checks New runs, takes rproxy's reports and
-// answers its own endpoints. It passes nothing to an app. rproxy applies
-// the size and time limits to the visitor, so their settings do not apply
-// here. Go's default limit on a request's line and headers, 1 MiB, stays:
-// it is far above rproxy's, and a question refused for its size would have
-// rproxy let the request through.
-func NewServeWAF(params Params) *Server {
-	cfg := *params.Config
-	cfg.RequestMaxBytes = 0
-	cfg.ClientRequestTimeout = serveWAFTimeout
-	// The server's WriteTimeout does this. It sets a new deadline for each
-	// request, where a deadline a handler sets stays on a kept-open
-	// connection, and would run out under a later request's answer.
-	cfg.ClientResponseTimeout = 0
-	// A question's body of QuestionBodyMaxBytes may be cut short, and the
-	// Core Rule Set does not read a JSON or XML body over its limit.
-	cfg.WAFBodyLimit = min(cfg.WAFBodyLimit, QuestionBodyMaxBytes-1)
-	params.Config = &cfg
-
+// New returns the server `smallwebwaf servewaf` runs. It answers
+// rproxy's questions, takes rproxy's reports and answers its own endpoints. It
+// passes nothing to an app. rproxy applies the size and time limits to the
+// visitor. Go's default limit on a request's line and headers, 1 MiB, stays: it
+// is far above rproxy's, and a question refused for its size would have rproxy
+// let the request through.
+func New(params Params) *Server {
 	h := newHandler(params)
 
-	awaitingReport, err := lru.New[string, *decision](maxAwaitingReport)
-	if err != nil {
-		panic(err) // New fails only for a size below one
+	return &Server{
+		Server: &http.Server{
+			Addr:         params.Config.ListenAddr,
+			Handler:      h,
+			ErrorLog:     slog.NewLogLogger(params.ProcessLog.Handler(), slog.LevelWarn),
+			ReadTimeout:  serveWAFTimeout,
+			WriteTimeout: serveWAFTimeout,
+			IdleTimeout:  serveWAFIdleTimeout,
+		},
+		Ledger:     h.ledger,
+		Limiter:    h.limiter,
+		GeoJS:      h.geojs,
+		Anomalies:  h.anomalies,
+		LookupFile: h.lookupFile,
+		Lists:      h.lists,
+		DNSBL:      h.dnsbl,
+		AbuseIPDB:  h.abuseIPDB,
+		Metrics:    h.metrics,
 	}
-
-	h.awaitingReport = awaitingReport
-
-	return h.server(&http.Server{
-		Handler:      http.HandlerFunc(h.serveWAF),
-		ReadTimeout:  serveWAFTimeout,
-		WriteTimeout: serveWAFTimeout,
-		IdleTimeout:  serveWAFIdleTimeout,
-	})
 }
 
-// serveWAF handles one request to servewaf: a request carrying
-// ClientHeader is rproxy's question, and any other is for servewaf itself.
-func (h *handler) serveWAF(w http.ResponseWriter, r *http.Request) {
+// ServeHTTP handles one request to servewaf: a request carrying ClientHeader is
+// rproxy's question, and any other is for servewaf itself.
+func (h *handler) ServeHTTP(w http.ResponseWriter, r *http.Request) {
 	if len(r.Header.Values(ClientHeader)) > 0 {
 		h.answerQuestion(w, r)
 
@@ -153,60 +139,22 @@ func (h *handler) serveWAF(w http.ResponseWriter, r *http.Request) {
 	h.answerOwnEndpoint(w, r)
 }
 
-// answersQuestions reports whether h is servewaf, which alone holds requests
-// for their reports.
-func (h *handler) answersQuestions() bool {
-	return h.awaitingReport != nil
-}
-
 // refusedWhateverTheAnswer reports whether the request is one that does not wait
 // for GeoJS, since the checks will refuse it at now whatever GeoJS answers about
-// its client: it is over the header limits, a blocklist lists its client while
-// SWWAF_BLOCKLIST_ACTION is deny, the CrowdSec decision list lists it, or it is
-// over a whole rate limit. In observe mode, which refuses nothing, none is.
-// rproxy lets a request through when servewaf answers too late.
+// its client: the heuristic crowdsec, header_limits, blocklists or rate_limits
+// will refuse it, as a function in that heuristic's file says. In observe mode,
+// which refuses nothing, none is. rproxy lets a request through when servewaf
+// answers too late.
 func (rq *request) refusedWhateverTheAnswer(now time.Time) bool {
 	if rq.h.config.Observe {
 		return false
 	}
 
-	lists := rq.h.lists
-	_, decided := lists.CrowdSecDecision(rq.client, now)
+	_, decided := rq.crowdSecDecisionInForce(now)
 
-	return decided || rq.overHeaderLimits() ||
-		(rq.h.config.BlocklistAction == deny && len(lists.ListedBy(rq.client)) > 0) ||
-		(rq.countedByRateLimits() &&
-			rq.h.limiter.OverARateLimit(rq.h.clientGroup(rq.client), now))
-}
-
-// overHeaderLimits reports whether servewaf refuses the request for its
-// headers: it has more than maxHeaderFields fields, each value of a header sent
-// twice being one, or more than maxCookies cookies, each part of a Cookie header
-// between semicolons being one unless it is empty or only spaces and tabs. The
-// Core Rule Set runs each of its rules on each cookie, so that thousands of small
-// cookies keep it busy for over a second. It trims only spaces and control
-// characters, of which a header value can hold only tabs, so a part of Unicode
-// spaces is a cookie to it.
-func (rq *request) overHeaderLimits() bool {
-	if !rq.h.answersQuestions() {
-		return false
-	}
-
-	fields, cookies := 0, 0
-
-	for _, values := range rq.in.Header {
-		fields += len(values)
-	}
-
-	for _, value := range rq.in.Header.Values("Cookie") {
-		for part := range strings.SplitSeq(value, ";") {
-			if strings.Trim(part, " \t") != "" {
-				cookies++
-			}
-		}
-	}
-
-	return fields > maxHeaderFields || cookies > maxCookies
+	return decided || overHeaderLimits(rq.headerCounts()) ||
+		rq.refusedByBlocklists(rq.h.lists.ListedBy(rq.client)) ||
+		rq.overAWholeRateLimit(now)
 }
 
 // answerQuestion runs the checks on the visitor's request a question
@@ -237,17 +185,18 @@ func (h *handler) answerQuestion(w http.ResponseWriter, r *http.Request) {
 
 	if refused == nil && !underOwnPrefix {
 		// In observe mode, what enforce mode would have refused counts here.
-		defer rq.countRefusal()
+		defer rq.runAfterAnswer(r.Context())
 
 		rq.allow()
 
 		return
 	}
 
-	// The last deferred runs first, as in ServeHTTP.
+	// The last deferred runs first: runAfterAnswer before addToHistory, so that
+	// a broken refusal limit is in the client's history.
 	defer rq.addToHistory()
 	defer rq.countAnomalies()
-	defer rq.countRefusal()
+	defer rq.runAfterAnswer(r.Context())
 
 	if refused != nil {
 		rq.deny(*refused)
@@ -374,10 +323,11 @@ func (rq *request) holdForReport() {
 
 // deny answers a question with what the visitor is to get for r.
 func (rq *request) deny(r refusal) {
+	rq.refused = &r
+
 	if r.status == 0 {
 		// SWWAF_BAN_RESPONSE is close. Written past rq.out, since the log line's
 		// status stays 0: the visitor is sent nothing.
-		rq.refused.CompareAndSwap(nil, &r)
 		rq.out.Header().Set(DispositionHeader, DispositionClose)
 		rq.out.ResponseWriter.WriteHeader(http.StatusOK)
 
@@ -385,7 +335,7 @@ func (rq *request) deny(r refusal) {
 	}
 
 	rq.out.Header().Set(DispositionHeader, DispositionDeny)
-	rq.answer(r)
+	http.Error(rq.out, http.StatusText(r.status), r.status)
 }
 
 // answerOwnEndpoint answers a request to servewaf's own address. No check
@@ -425,9 +375,10 @@ func (h *handler) takeReport(w http.ResponseWriter, r *http.Request) {
 	}
 
 	held, found := h.awaitingReport.Peek(report.RequestID)
-	// Remove reports true to one report only, of several that name the id.
+	// Remove reports true to one report only, of several that name the id. A
+	// question still being handled is held as nil.
 	if found && held != nil && h.awaitingReport.Remove(report.RequestID) {
-		h.finishWith(held, report)
+		h.finishWith(r.Context(), held, report)
 	}
 
 	w.WriteHeader(http.StatusNoContent)
@@ -490,18 +441,17 @@ func (report *Report) checkRanges() error {
 
 // finishWith finishes a request with what its report says, and writes the
 // request's last log line, which holds its decision's fields and the report's.
-// For an allowed request it first takes the steps ServeHTTP takes once a
-// request passed to the app has ended, with the status and bytes of the report
-// in place of those it would have seen. A denied request's counting was
-// finished at its decision.
-func (h *handler) finishWith(held *decision, report Report) {
+// For an allowed request it first runs the heuristics of onReport, and adds the
+// request to its client's history, the anomaly counters and the metrics, with
+// the status and bytes the report gives. A denied request's counting was
+// finished at its decision. ctx is the report's own context.
+func (h *handler) finishWith(ctx context.Context, held *decision, report Report) {
 	rq := &request{
-		decision: *held,
-		h:        h,
-		out:      &responseWriter{status: report.Status, bytes: report.ResponseBytes},
-		body:     &requestBody{},
+		decision:     *held,
+		h:            h,
+		out:          &responseWriter{status: report.Status, bytes: report.ResponseBytes},
+		requestBytes: report.RequestBytes,
 	}
-	rq.body.bytes.Store(report.RequestBytes)
 
 	rq.line.ServeWAFLine = requestlog.ServeWAFLineReport
 	rq.line.Status = report.Status
@@ -511,10 +461,8 @@ func (h *handler) finishWith(held *decision, report Report) {
 
 	if rq.allowed {
 		rq.line.DurationUpstreamTotal = &report.DurationUpstreamTotal
-		// addToHistory goes by this for whether the request reached the app.
-		rq.upstreamStart = time.Now()
 
-		rq.countBytes()
+		rq.runBanningHeuristics(ctx, onReport())
 		rq.countAnomalies()
 		rq.addToHistory()
 

internal/servewaf/servewaf_test.go

@@ -1,4 +1,4 @@
-package proxy_test
+package servewaf_test
 
 import (
 	"context"
@@ -19,9 +19,9 @@ import (
 
 	"sneak.berlin/go/smallwebwaf/internal/alerts"
 	"sneak.berlin/go/smallwebwaf/internal/bans"
-	"sneak.berlin/go/smallwebwaf/internal/proxy"
 	"sneak.berlin/go/smallwebwaf/internal/ratelimit"
 	"sneak.berlin/go/smallwebwaf/internal/requestlog"
+	"sneak.berlin/go/smallwebwaf/internal/servewaf"
 )
 
 const (
@@ -57,7 +57,7 @@ type serveWAF struct {
 	t      *testing.T
 	addr   string
 	out    *output
-	server *proxy.Server
+	server *servewaf.Server
 	clock  *clock
 	queue  *alerts.Queue
 }
@@ -67,13 +67,13 @@ type serveWAF struct {
 func startServeWAF(t *testing.T, geojsURL string, env map[string]string) *serveWAF {
 	t.Helper()
 
-	return startServeWAFWith(t, geojsURL, env, func(*proxy.Server) {})
+	return startServeWAFWith(t, geojsURL, env, func(*servewaf.Server) {})
 }
 
 // startServeWAFWith is startServeWAF with change applied to the server before
 // it starts.
 func startServeWAFWith(
-	t *testing.T, geojsURL string, env map[string]string, change func(*proxy.Server),
+	t *testing.T, geojsURL string, env map[string]string, change func(*servewaf.Server),
 ) *serveWAF {
 	t.Helper()
 
@@ -84,26 +84,12 @@ func startServeWAFWith(
 	}
 	maps.Copy(settings, env)
 
-	server, out, queue := newServerWith(t, proxy.NewServeWAF,
-		"http://127.0.0.1:8081", geojsURL, clk.Now, settings)
+	server, out, queue := newServeWAF(t, geojsURL, clk.Now, settings)
 	change(server)
-
-	listener, err := (&net.ListenConfig{}).Listen(t.Context(), "tcp", localhost+":0")
-	if err != nil {
-		t.Fatalf("listen: %v", err)
-	}
-
-	go func() {
-		_ = server.Serve(listener)
-	}()
-
-	t.Cleanup(func() {
-		_ = server.Close()
-	})
+	serve(t, server)
 
 	return &serveWAF{
-		t: t, addr: listener.Addr().String(), out: out, server: server,
-		clock: clk, queue: queue,
+		t: t, addr: server.Addr, out: out, server: server, clock: clk, queue: queue,
 	}
 }
 
@@ -117,8 +103,8 @@ func (s *serveWAF) questionWith(
 
 	req := newRequest(s.t, method, s.addr, path, body)
 	req.Host = host
-	req.Header.Set(proxy.ClientHeader, from)
-	req.Header.Set(proxy.PeerHeader, rproxyPeer)
+	req.Header.Set(servewaf.ClientHeader, from)
+	req.Header.Set(servewaf.PeerHeader, rproxyPeer)
 	req.Header.Set(requestIDHeader, rand.Text())
 
 	return req
@@ -145,13 +131,13 @@ func (s *serveWAF) allowed(from string) string {
 	s.t.Helper()
 
 	req := s.question(siteA, from, "/")
-	wantDisposition(s.t, do(s.t, req), http.StatusOK, proxy.DispositionAllow)
+	wantDisposition(s.t, do(s.t, req), http.StatusOK, servewaf.DispositionAllow)
 
 	return req.Header.Get(requestIDHeader)
 }
 
 // report sends rproxy's report and returns the answer.
-func (s *serveWAF) report(report proxy.Report) answer {
+func (s *serveWAF) report(report servewaf.Report) answer {
 	s.t.Helper()
 
 	body, err := json.Marshal(report)
@@ -166,7 +152,7 @@ func (s *serveWAF) report(report proxy.Report) answer {
 func (s *serveWAF) reportBody(body string) answer {
 	s.t.Helper()
 
-	return do(s.t, newRequest(s.t, http.MethodPost, s.addr, proxy.ReportPath,
+	return do(s.t, newRequest(s.t, http.MethodPost, s.addr, servewaf.ReportPath,
 		strings.NewReader(body)))
 }
 
@@ -175,7 +161,7 @@ func (s *serveWAF) reportBody(body string) answer {
 func (s *serveWAF) passedOn(from string) {
 	s.t.Helper()
 
-	got := s.report(proxy.Report{
+	got := s.report(servewaf.Report{
 		RequestID:     s.allowed(from),
 		Status:        http.StatusOK,
 		RequestBytes:  bodyBytes,
@@ -196,7 +182,7 @@ func (s *serveWAF) history() ratelimit.History {
 func (s *serveWAF) metrics() string {
 	s.t.Helper()
 
-	req := newRequest(s.t, http.MethodGet, s.addr, proxy.MetricsPath, http.NoBody)
+	req := newRequest(s.t, http.MethodGet, s.addr, servewaf.MetricsPath, http.NoBody)
 	req.Header.Set("Authorization", bearer)
 
 	got := do(s.t, req)
@@ -210,7 +196,7 @@ func wantDisposition(t *testing.T, got answer, status int, disposition string) {
 	t.Helper()
 	wantStatus(t, got, status)
 
-	if answered := got.header.Get(proxy.DispositionHeader); answered != disposition {
+	if answered := got.header.Get(servewaf.DispositionHeader); answered != disposition {
 		t.Errorf("answered with disposition %q, want %q", answered, disposition)
 	}
 }
@@ -262,10 +248,10 @@ func TestQuestionAllowedIsAnsweredAndLogged(t *testing.T) {
 	req := s.question(siteA, client, "/page?q=1&token=visible")
 	req.Header.Set(requestIDHeader, "the-id")
 	req.Header.Set("X-Forwarded-Proto", "https")
-	req.Header.Set(proxy.ContentLengthHeader, "1234")
+	req.Header.Set(servewaf.ContentLengthHeader, "1234")
 
 	got := do(t, req)
-	wantDisposition(t, got, http.StatusOK, proxy.DispositionAllow)
+	wantDisposition(t, got, http.StatusOK, servewaf.DispositionAllow)
 	wantBody(t, got, "")
 
 	if id := got.header.Get(requestIDHeader); id != "" {
@@ -292,7 +278,7 @@ func TestIPv6VisitorIsCountedInItsGroup(t *testing.T) {
 	s.allowed("2001:db8::1")
 
 	got := s.ask("2001:db8::2", "/")
-	wantDisposition(t, got, http.StatusForbidden, proxy.DispositionDeny)
+	wantDisposition(t, got, http.StatusForbidden, servewaf.DispositionDeny)
 }
 
 func TestIPv4VisitorInIPv6FormIsTheIPv4Client(t *testing.T) {
@@ -301,9 +287,9 @@ func TestIPv4VisitorInIPv6FormIsTheIPv4Client(t *testing.T) {
 	s := startServeWAF(t, "", map[string]string{denyNets: client})
 
 	req := s.question(siteA, "::ffff:"+client, "/")
-	req.Header.Set(proxy.PeerHeader, "::ffff:"+rproxyPeer)
+	req.Header.Set(servewaf.PeerHeader, "::ffff:"+rproxyPeer)
 
-	wantDisposition(t, do(t, req), http.StatusForbidden, proxy.DispositionDeny)
+	wantDisposition(t, do(t, req), http.StatusForbidden, servewaf.DispositionDeny)
 
 	line := s.out.requestLine(t)
 	if line.ClientIP != client || line.PeerIP != rproxyPeer {
@@ -319,13 +305,13 @@ func TestMalformedQuestionGets400AndAWarningAndNoLine(t *testing.T) {
 		change func(*http.Request)
 	}{
 		{"client not an address", func(req *http.Request) {
-			req.Header.Set(proxy.ClientHeader, "not an address")
+			req.Header.Set(servewaf.ClientHeader, "not an address")
 		}},
 		{"client empty", func(req *http.Request) {
-			req.Header.Set(proxy.ClientHeader, "")
+			req.Header.Set(servewaf.ClientHeader, "")
 		}},
 		{"client address with a zone", func(req *http.Request) {
-			req.Header.Set(proxy.ClientHeader, "2001:db8::1%eth0")
+			req.Header.Set(servewaf.ClientHeader, "2001:db8::1%eth0")
 		}},
 		{"id absent", func(req *http.Request) {
 			req.Header.Del(requestIDHeader)
@@ -367,7 +353,7 @@ func TestLongestValidIDIsTaken(t *testing.T) {
 
 	req := s.question(siteA, client, "/")
 	req.Header.Set(requestIDHeader, strings.Repeat("x", 128))
-	wantDisposition(t, do(t, req), http.StatusOK, proxy.DispositionAllow)
+	wantDisposition(t, do(t, req), http.StatusOK, servewaf.DispositionAllow)
 }
 
 func TestQuestionWithABodyOver64KiBGets400(t *testing.T) {
@@ -375,15 +361,15 @@ func TestQuestionWithABodyOver64KiBGets400(t *testing.T) {
 
 	s := startServeWAF(t, "", nil)
 
-	over := strings.NewReader(strings.Repeat("x", proxy.QuestionBodyMaxBytes+1))
+	over := strings.NewReader(strings.Repeat("x", servewaf.QuestionBodyMaxBytes+1))
 	got := do(t, s.questionWith(http.MethodPost, siteA, client, "/", over))
 	wantDisposition(t, got, http.StatusBadRequest, "")
 	wantProcessMessages(t, s, "a question is refused", 1)
 	wantNoRequestLines(t, s)
 
-	whole := strings.NewReader(strings.Repeat("x", proxy.QuestionBodyMaxBytes))
+	whole := strings.NewReader(strings.Repeat("x", servewaf.QuestionBodyMaxBytes))
 	got = do(t, s.questionWith(http.MethodPost, siteA, client, "/", whole))
-	wantDisposition(t, got, http.StatusOK, proxy.DispositionAllow)
+	wantDisposition(t, got, http.StatusOK, servewaf.DispositionAllow)
 }
 
 func TestQuestionWithAHeldIDIsRefused(t *testing.T) {
@@ -399,15 +385,15 @@ func TestQuestionWithAHeldIDIsRefused(t *testing.T) {
 	wantProcessMessages(t, s, "a question is refused", 1)
 
 	// A denied request's id is held as well.
-	denied := s.question(siteA, otherClient, proxy.HealthPath)
-	wantDisposition(t, do(t, denied), http.StatusNotFound, proxy.DispositionDeny)
+	denied := s.question(siteA, otherClient, servewaf.HealthPath)
+	wantDisposition(t, do(t, denied), http.StatusNotFound, servewaf.DispositionDeny)
 
 	again = s.question(siteA, client, "/")
 	again.Header.Set(requestIDHeader, denied.Header.Get(requestIDHeader))
 	wantDisposition(t, do(t, again), http.StatusBadRequest, "")
 
 	// The report ends the holding, and the refused questions changed nothing.
-	got := s.report(proxy.Report{RequestID: id, ResponseBytes: answerBytes})
+	got := s.report(servewaf.Report{RequestID: id, ResponseBytes: answerBytes})
 	wantStatus(t, got, http.StatusNoContent)
 
 	if history := s.history(); history.ResponseBytes != answerBytes {
@@ -416,7 +402,7 @@ func TestQuestionWithAHeldIDIsRefused(t *testing.T) {
 
 	again = s.question(siteA, client, "/")
 	again.Header.Set(requestIDHeader, id)
-	wantDisposition(t, do(t, again), http.StatusOK, proxy.DispositionAllow)
+	wantDisposition(t, do(t, again), http.StatusOK, servewaf.DispositionAllow)
 }
 
 func TestReportNeverReachesAQuestionStillBeingHandled(t *testing.T) {
@@ -450,7 +436,7 @@ func TestReportNeverReachesAQuestionStillBeingHandled(t *testing.T) {
 
 	// A report for a question not yet answered is ignored, and that question's
 	// id is taken.
-	got := s.report(proxy.Report{RequestID: id, ResponseBytes: 1000})
+	got := s.report(servewaf.Report{RequestID: id, ResponseBytes: 1000})
 	wantStatus(t, got, http.StatusNoContent)
 
 	// This would wait on the same lookup were the id not taken.
@@ -465,7 +451,7 @@ func TestReportNeverReachesAQuestionStillBeingHandled(t *testing.T) {
 
 	select {
 	case got := <-answered:
-		wantDisposition(t, got, http.StatusOK, proxy.DispositionAllow)
+		wantDisposition(t, got, http.StatusOK, servewaf.DispositionAllow)
 	case <-time.After(waitLimit):
 		t.Fatal("the question got no answer")
 	}
@@ -480,7 +466,7 @@ func TestReportNeverReachesAQuestionStillBeingHandled(t *testing.T) {
 	}
 
 	// The true report comes after, and is the one that counts.
-	got = s.report(proxy.Report{RequestID: id, ResponseBytes: answerBytes})
+	got = s.report(servewaf.Report{RequestID: id, ResponseBytes: answerBytes})
 	wantStatus(t, got, http.StatusNoContent)
 
 	if history := s.history(); history.ResponseBytes != answerBytes {
@@ -498,13 +484,13 @@ func TestPeerAbsentOrUnreadableIsAnsweredAndLoggedInvalid(t *testing.T) {
 			s := startServeWAF(t, "", nil)
 
 			req := s.question(siteA, client, "/")
-			req.Header.Del(proxy.PeerHeader)
+			req.Header.Del(servewaf.PeerHeader)
 
 			if peer != "" {
-				req.Header.Set(proxy.PeerHeader, peer)
+				req.Header.Set(servewaf.PeerHeader, peer)
 			}
 
-			wantDisposition(t, do(t, req), http.StatusOK, proxy.DispositionAllow)
+			wantDisposition(t, do(t, req), http.StatusOK, servewaf.DispositionAllow)
 
 			if line := s.out.requestLine(t); line.PeerIP != "invalid IP" {
 				t.Errorf("log line has peer_ip %q, want invalid IP", line.PeerIP)
@@ -525,8 +511,8 @@ func TestContentLengthUnreadableOrNegativeCountsAsAbsent(t *testing.T) {
 			})
 
 			req := s.question(siteA, client, "/")
-			req.Header.Set(proxy.ContentLengthHeader, announced)
-			wantDisposition(t, do(t, req), http.StatusOK, proxy.DispositionAllow)
+			req.Header.Set(servewaf.ContentLengthHeader, announced)
+			wantDisposition(t, do(t, req), http.StatusOK, servewaf.DispositionAllow)
 
 			if line := s.out.requestLine(t); line.ContentLength != 0 {
 				t.Errorf("log line has content_length %d, want none", line.ContentLength)
@@ -541,13 +527,13 @@ func TestHeaderSentTwiceUsesItsFirstValue(t *testing.T) {
 	s := startServeWAF(t, "", nil)
 
 	req := s.question(siteA, client, "/")
-	req.Header.Add(proxy.ClientHeader, otherClient)
-	req.Header.Add(proxy.PeerHeader, "172.18.0.3")
+	req.Header.Add(servewaf.ClientHeader, otherClient)
+	req.Header.Add(servewaf.PeerHeader, "172.18.0.3")
 	req.Header.Set(requestIDHeader, "first")
 	req.Header.Add(requestIDHeader, "second")
-	req.Header.Set(proxy.ContentLengthHeader, "1234")
-	req.Header.Add(proxy.ContentLengthHeader, "5678")
-	wantDisposition(t, do(t, req), http.StatusOK, proxy.DispositionAllow)
+	req.Header.Set(servewaf.ContentLengthHeader, "1234")
+	req.Header.Add(servewaf.ContentLengthHeader, "5678")
+	wantDisposition(t, do(t, req), http.StatusOK, servewaf.DispositionAllow)
 
 	line := s.out.requestLine(t)
 	if line.ClientIP != client || line.PeerIP != rproxyPeer ||
@@ -576,7 +562,7 @@ func sendQuestionWithPartOfItsBody(t *testing.T, conn net.Conn) {
 	_, err := fmt.Fprintf(conn,
 		"POST / HTTP/1.1\r\nHost: %s\r\n%s: %s\r\n%s: an-id\r\n"+
 			"Content-Length: 100\r\n\r\npart",
-		siteA, proxy.ClientHeader, client, requestIDHeader)
+		siteA, servewaf.ClientHeader, client, requestIDHeader)
 	if err != nil {
 		t.Fatalf("send the question: %v", err)
 	}
@@ -606,7 +592,7 @@ func TestQuestionWhoseBodyStopsArrivingGetsNoAnswer(t *testing.T) {
 			t.Parallel()
 
 			s := startServeWAFWith(t, "", map[string]string{metricsToken: token},
-				func(server *proxy.Server) { server.ReadTimeout = readTimeout })
+				func(server *servewaf.Server) { server.ReadTimeout = readTimeout })
 
 			conn := dial(t, s.addr)
 			sendQuestionWithPartOfItsBody(t, conn)
@@ -626,13 +612,10 @@ func TestQuestionWhoseBodyStopsArrivingGetsNoAnswer(t *testing.T) {
 			wantProcessMessages(t, s, "a question's body stopped arriving", 1)
 			wantNoRequestLines(t, s)
 
-			// The id was not taken, and the metrics count nothing for it.
+			// The id was not taken.
 			again := s.question(siteA, client, "/")
 			again.Header.Set(requestIDHeader, "an-id")
-			wantDisposition(t, do(t, again), http.StatusOK, proxy.DispositionAllow)
-			wantNoSeries(t, s.metrics(),
-				`smallwebwaf_size_and_time_limit_hits_total{instance="`+alertInstance+
-					`",limit="SWWAF_CLIENT_REQUEST_TIMEOUT"}`)
+			wantDisposition(t, do(t, again), http.StatusOK, servewaf.DispositionAllow)
 		})
 	}
 }
@@ -649,7 +632,7 @@ func TestQuestionDeniedGetsTheBanResponse(t *testing.T) {
 			})
 
 			got := s.ask(client, "/")
-			wantDisposition(t, got, status, proxy.DispositionDeny)
+			wantDisposition(t, got, status, servewaf.DispositionDeny)
 			wantBody(t, got, http.StatusText(status)+"\n")
 			wantLine(t, s.out.requestLine(t), status, requestlog.ActionDenied)
 		})
@@ -664,7 +647,7 @@ func TestBanResponseCloseIsAnAnswerOfItsOwn(t *testing.T) {
 	})
 
 	got := s.ask(client, "/")
-	wantDisposition(t, got, http.StatusOK, proxy.DispositionClose)
+	wantDisposition(t, got, http.StatusOK, servewaf.DispositionClose)
 	wantBody(t, got, "")
 	// The visitor is sent nothing.
 	wantLine(t, s.out.requestLine(t), 0, requestlog.ActionDenied)
@@ -681,12 +664,12 @@ func TestBlockRuleIsDeniedWith403AndABanRuleWithTheBanResponse(t *testing.T) {
 	})
 
 	got := s.ask(client, "/blocked")
-	wantDisposition(t, got, http.StatusForbidden, proxy.DispositionDeny)
+	wantDisposition(t, got, http.StatusForbidden, servewaf.DispositionDeny)
 	wantLine(t, s.out.requestLine(t), http.StatusForbidden,
 		requestlog.ActionRuleBlocked)
 
 	got = s.ask(client, "/.env")
-	wantDisposition(t, got, http.StatusTooManyRequests, proxy.DispositionDeny)
+	wantDisposition(t, got, http.StatusTooManyRequests, servewaf.DispositionDeny)
 	wantLine(t, s.out.requestLines(t, 2)[1], http.StatusTooManyRequests,
 		requestlog.ActionBanned)
 }
@@ -698,15 +681,17 @@ func TestQuestionUnderTheOwnPrefixIsDeniedWith404AfterTheChecks(t *testing.T) {
 		metricsToken: token, denyNets: otherClient,
 	})
 
-	for _, path := range []string{proxy.HealthPath, proxy.MetricsPath, proxy.ReportPath} {
+	for _, path := range []string{
+		servewaf.HealthPath, servewaf.MetricsPath, servewaf.ReportPath,
+	} {
 		got := s.ask(client, path)
-		wantDisposition(t, got, http.StatusNotFound, proxy.DispositionDeny)
+		wantDisposition(t, got, http.StatusNotFound, servewaf.DispositionDeny)
 	}
 
 	wantLine(t, s.out.requestLine(t), http.StatusNotFound, requestlog.ActionAdmin)
 
-	got := s.ask(otherClient, proxy.MetricsPath)
-	wantDisposition(t, got, http.StatusForbidden, proxy.DispositionDeny)
+	got := s.ask(otherClient, servewaf.MetricsPath)
+	wantDisposition(t, got, http.StatusForbidden, servewaf.DispositionDeny)
 }
 
 func TestObserveModeAllowsAndLogsWhatEnforceModeWouldHaveDone(t *testing.T) {
@@ -715,7 +700,7 @@ func TestObserveModeAllowsAndLogsWhatEnforceModeWouldHaveDone(t *testing.T) {
 	s := startServeWAF(t, "", map[string]string{mode: observe, denyNets: client})
 
 	got := s.ask(client, "/")
-	wantDisposition(t, got, http.StatusOK, proxy.DispositionAllow)
+	wantDisposition(t, got, http.StatusOK, servewaf.DispositionAllow)
 
 	line := s.out.requestLine(t)
 	wantLine(t, line, http.StatusOK, requestlog.ActionForward)
@@ -731,7 +716,7 @@ func TestObserveModeRefusalAnsweredAllowCountsForTheErrorBurst(t *testing.T) {
 
 	for range 2 {
 		got := s.ask(client, "/blocked")
-		wantDisposition(t, got, http.StatusOK, proxy.DispositionAllow)
+		wantDisposition(t, got, http.StatusOK, servewaf.DispositionAllow)
 	}
 
 	lines := s.out.requestLines(t, 2)
@@ -750,7 +735,7 @@ func TestDeniedQuestionCountsForTheErrorBurst(t *testing.T) {
 
 	for range 2 {
 		got := s.ask(client, "/blocked")
-		wantDisposition(t, got, http.StatusForbidden, proxy.DispositionDeny)
+		wantDisposition(t, got, http.StatusForbidden, servewaf.DispositionDeny)
 	}
 
 	lines := s.out.requestLines(t, 2)
@@ -779,7 +764,7 @@ func TestAllowCarriesTheLookupHeadersWhileTheSettingIsSet(t *testing.T) {
 			})
 
 			got := s.ask(fromDE, "/")
-			wantDisposition(t, got, http.StatusOK, proxy.DispositionAllow)
+			wantDisposition(t, got, http.StatusOK, servewaf.DispositionAllow)
 
 			asn, country := got.header.Get("X-Client-Asn"), got.header.Get("X-Client-Country")
 			if asn != tc.wantASN || country != tc.wantCountry {
@@ -804,7 +789,7 @@ func TestReportCountsTowardAByteLimitWhichThenBans(t *testing.T) {
 	}
 
 	// 100 bytes are over the limit of 99.
-	got := s.report(proxy.Report{
+	got := s.report(servewaf.Report{
 		RequestID: id, Status: http.StatusBadGateway,
 		RequestBytes: bodyBytes, ResponseBytes: answerBytes,
 	})
@@ -828,7 +813,7 @@ func TestReportCountsTowardAByteLimitWhichThenBans(t *testing.T) {
 	}
 
 	got = s.ask(client, "/")
-	wantDisposition(t, got, http.StatusForbidden, proxy.DispositionDeny)
+	wantDisposition(t, got, http.StatusForbidden, servewaf.DispositionDeny)
 }
 
 func TestReportCountsAtThePercentageItsQuestionWasGiven(t *testing.T) {
@@ -842,10 +827,10 @@ func TestReportCountsAtThePercentageItsQuestionWasGiven(t *testing.T) {
 	})
 
 	s.passedOn(fromKP)
-	wantDisposition(t, s.ask(fromKP, "/"), http.StatusOK, proxy.DispositionAllow)
+	wantDisposition(t, s.ask(fromKP, "/"), http.StatusOK, servewaf.DispositionAllow)
 
 	s.passedOn(fromDE)
-	wantDisposition(t, s.ask(fromDE, "/"), http.StatusForbidden, proxy.DispositionDeny)
+	wantDisposition(t, s.ask(fromDE, "/"), http.StatusForbidden, servewaf.DispositionDeny)
 }
 
 func TestReportAddsTheRequestToItsClientsHistoryAndTheAnomalyCounters(t *testing.T) {
@@ -863,7 +848,7 @@ func TestReportAddsTheRequestToItsClientsHistoryAndTheAnomalyCounters(t *testing
 		t.Errorf("anomaly counters %v before the report, want none", counters)
 	}
 
-	got := s.report(proxy.Report{
+	got := s.report(servewaf.Report{
 		RequestID: id, Status: http.StatusBadGateway,
 		RequestBytes: bodyBytes, ResponseBytes: answerBytes,
 	})
@@ -891,7 +876,7 @@ func TestDeniedRequestIsFinishedAtItsDecision(t *testing.T) {
 	s.allowed(client)
 
 	denied := s.question(siteA, client, "/")
-	wantDisposition(t, do(t, denied), http.StatusForbidden, proxy.DispositionDeny)
+	wantDisposition(t, do(t, denied), http.StatusForbidden, servewaf.DispositionDeny)
 
 	counters := s.server.Anomalies.Snapshot()
 	if len(counters) != 1 || counters[0].Minute.Current != 1 {
@@ -908,7 +893,7 @@ func TestDeniedRequestIsFinishedAtItsDecision(t *testing.T) {
 
 	wantMetric(t, s.metrics(), series, 1)
 
-	got := s.report(proxy.Report{
+	got := s.report(servewaf.Report{
 		RequestID: denied.Header.Get(requestIDHeader), Status: http.StatusForbidden,
 		ResponseBytes: 1000, DurationTotal: 2,
 	})
@@ -941,7 +926,7 @@ func TestMetricsCountAnAllowedRequestFromItsReport(t *testing.T) {
 	wantMetric(t, metrics, `smallwebwaf_requests_in_flight{instance="`+alertInstance+`"}`,
 		1) // the scrape itself
 
-	got := s.report(proxy.Report{
+	got := s.report(servewaf.Report{
 		RequestID: id, Status: http.StatusBadGateway,
 		RequestBytes: bodyBytes, ResponseBytes: answerBytes,
 		DurationTotal: 5, DurationUpstreamTotal: 4,
@@ -959,7 +944,7 @@ func TestMetricsCountAnAllowedRequestFromItsReport(t *testing.T) {
 	// check needs a server that has not been scraped yet.
 	unscraped := startServeWAF(t, "", map[string]string{metricsToken: token})
 
-	got = unscraped.report(proxy.Report{
+	got = unscraped.report(servewaf.Report{
 		RequestID: unscraped.allowed(client), Status: http.StatusBadGateway, DurationTotal: 5,
 	})
 	wantStatus(t, got, http.StatusNoContent)
@@ -972,7 +957,7 @@ func TestReportForARequestNotHeldIsIgnored(t *testing.T) {
 
 	s := startServeWAF(t, "", map[string]string{bytesLimitPerMinute: byteLimit})
 
-	got := s.report(proxy.Report{RequestID: "no-such-request", ResponseBytes: 1000})
+	got := s.report(servewaf.Report{RequestID: "no-such-request", ResponseBytes: 1000})
 	wantStatus(t, got, http.StatusNoContent)
 
 	if clients := s.server.Limiter.Snapshot(); len(clients) != 0 {
@@ -989,7 +974,7 @@ func TestReportForARequestNotHeldIsIgnored(t *testing.T) {
 	// A second report of the same request does not count it twice.
 	id := s.allowed(client)
 	for range 2 {
-		got = s.report(proxy.Report{RequestID: id, ResponseBytes: answerBytes})
+		got = s.report(servewaf.Report{RequestID: id, ResponseBytes: answerBytes})
 		wantStatus(t, got, http.StatusNoContent)
 	}
 
@@ -1177,7 +1162,7 @@ func TestBytesAtTheirMostEachWayBanRatherThanOverflow(t *testing.T) {
 
 	s := startServeWAF(t, "", map[string]string{bytesLimitPerMinute: byteLimit})
 
-	got := s.report(proxy.Report{
+	got := s.report(servewaf.Report{
 		RequestID: s.allowed(client), Status: http.StatusOK,
 		RequestBytes: reportedBytesLimit, ResponseBytes: reportedBytesLimit,
 	})
@@ -1262,9 +1247,9 @@ func TestReportWritesTheLastLineWithTheDecisionsAndTheReportsFields(t *testing.T
 	req.Header.Set("X-Forwarded-Proto", "https")
 	id := req.Header.Get(requestIDHeader)
 
-	wantDisposition(t, do(t, req), http.StatusOK, proxy.DispositionAllow)
+	wantDisposition(t, do(t, req), http.StatusOK, servewaf.DispositionAllow)
 
-	got := s.report(proxy.Report{
+	got := s.report(servewaf.Report{
 		RequestID: id, Status: http.StatusCreated,
 		RequestBytes: bodyBytes, ResponseBytes: answerBytes,
 		DurationTotal: 12.5, DurationUpstreamTotal: 10.25,
@@ -1311,7 +1296,7 @@ func TestEveryDeniedRequestsReportGetsItsLastLine(t *testing.T) {
 			"close", map[string]string{denyNets: client, banResponse: banResponseClose}, "/",
 			0, requestlog.ActionDenied,
 		},
-		{"own prefix", nil, proxy.HealthPath, http.StatusNotFound, requestlog.ActionAdmin},
+		{"own prefix", nil, servewaf.HealthPath, http.StatusNotFound, requestlog.ActionAdmin},
 	} {
 		t.Run(tc.name, func(t *testing.T) {
 			t.Parallel()
@@ -1322,7 +1307,7 @@ func TestEveryDeniedRequestsReportGetsItsLastLine(t *testing.T) {
 			id := req.Header.Get(requestIDHeader)
 			do(t, req)
 
-			got := s.report(proxy.Report{
+			got := s.report(servewaf.Report{
 				RequestID: id, Status: tc.status, ResponseBytes: 8, DurationTotal: 3,
 			})
 			wantStatus(t, got, http.StatusNoContent)
@@ -1358,18 +1343,18 @@ func TestOldestAnsweredRequestIsDroppedPastTheBound(t *testing.T) {
 			t.Fatalf("question: %v", err)
 		}
 
-		wantDisposition(t, readAnswer(res), http.StatusOK, proxy.DispositionAllow)
+		wantDisposition(t, readAnswer(res), http.StatusOK, servewaf.DispositionAllow)
 	}
 
 	// The table is full again with next and those, without oldest.
-	got := s.report(proxy.Report{RequestID: oldest, ResponseBytes: answerBytes})
+	got := s.report(servewaf.Report{RequestID: oldest, ResponseBytes: answerBytes})
 	wantStatus(t, got, http.StatusNoContent)
 
 	if counted := s.history().Requests; counted != 0 {
 		t.Errorf("history holds %d requests, want the dropped one not counted", counted)
 	}
 
-	got = s.report(proxy.Report{RequestID: next, ResponseBytes: answerBytes})
+	got = s.report(servewaf.Report{RequestID: next, ResponseBytes: answerBytes})
 	wantStatus(t, got, http.StatusNoContent)
 
 	if counted := s.history().Requests; counted != 1 {
@@ -1383,10 +1368,10 @@ func TestBanMadeThroughOneHostRefusesTheClientOnAnother(t *testing.T) {
 	s := startServeWAF(t, "", map[string]string{rulesDir: writeRules(t, testRules)})
 
 	got := do(t, s.question(siteA, client, "/.env"))
-	wantDisposition(t, got, http.StatusForbidden, proxy.DispositionDeny)
+	wantDisposition(t, got, http.StatusForbidden, servewaf.DispositionDeny)
 
 	got = do(t, s.question(siteB, client, "/"))
-	wantDisposition(t, got, http.StatusForbidden, proxy.DispositionDeny)
+	wantDisposition(t, got, http.StatusForbidden, servewaf.DispositionDeny)
 
 	lines := s.out.requestLines(t, 2)
 	if lines[0].Host != siteA || lines[1].Host != siteB {
@@ -1412,7 +1397,7 @@ func TestRequestsOnEverySiteCountTowardOneSetOfLimits(t *testing.T) {
 	s.allowed(client)
 
 	got := do(t, s.question(siteB, client, "/"))
-	wantDisposition(t, got, http.StatusForbidden, proxy.DispositionDeny)
+	wantDisposition(t, got, http.StatusForbidden, servewaf.DispositionDeny)
 }
 
 func TestOwnEndpointsAnswerOnlyWithoutTheClientHeader(t *testing.T) {
@@ -1427,13 +1412,13 @@ func TestOwnEndpointsAnswerOnlyWithoutTheClientHeader(t *testing.T) {
 		path, authorization string
 		want                int
 	}{
-		{proxy.HealthPath, "", http.StatusOK},
-		{proxy.MetricsPath, bearer, http.StatusOK},
-		{proxy.MetricsPath, "", http.StatusUnauthorized},
-		{proxy.BansPath, adminBearer, http.StatusOK},
-		{proxy.BansPath, "", http.StatusUnauthorized},
-		{proxy.ClientsPath + client, adminBearer, http.StatusOK},
-		{proxy.ReportPath, "", http.StatusNotFound},
+		{servewaf.HealthPath, "", http.StatusOK},
+		{servewaf.MetricsPath, bearer, http.StatusOK},
+		{servewaf.MetricsPath, "", http.StatusUnauthorized},
+		{servewaf.BansPath, adminBearer, http.StatusOK},
+		{servewaf.BansPath, "", http.StatusUnauthorized},
+		{servewaf.ClientsPath + client, adminBearer, http.StatusOK},
+		{servewaf.ReportPath, "", http.StatusNotFound},
 		{"/_smallwebwaf/other", "", http.StatusNotFound},
 		{"/", "", http.StatusNotFound},
 	} {
@@ -1446,9 +1431,9 @@ func TestOwnEndpointsAnswerOnlyWithoutTheClientHeader(t *testing.T) {
 		req.Header.Set("Authorization", tc.authorization)
 
 		if strings.HasPrefix(tc.path, "/_smallwebwaf/") {
-			wantDisposition(t, do(t, req), http.StatusNotFound, proxy.DispositionDeny)
+			wantDisposition(t, do(t, req), http.StatusNotFound, servewaf.DispositionDeny)
 		} else {
-			wantDisposition(t, do(t, req), http.StatusOK, proxy.DispositionAllow)
+			wantDisposition(t, do(t, req), http.StatusOK, servewaf.DispositionAllow)
 		}
 	}
 }
@@ -1458,33 +1443,28 @@ func TestOwnEndpointsLinesDoNotSayWhichOfTheTwoTheyAre(t *testing.T) {
 
 	s := startServeWAF(t, "", nil)
 
-	wantStatus(t, get(t, s.addr, proxy.HealthPath), http.StatusOK)
+	wantStatus(t, get(t, s.addr, servewaf.HealthPath), http.StatusOK)
 
 	line := s.out.requestLine(t)
-	if _, there := line.fields["servewaf_line"]; there || line.Path != proxy.HealthPath {
+	if _, there := line.fields["servewaf_line"]; there ||
+		line.Path != servewaf.HealthPath {
 		t.Errorf("the health check's log line is %+v", line.fields)
 	}
 }
 
-func TestSettingsOfTheLimitsAndTheProxiesAreIgnored(t *testing.T) {
+func TestALargeBodyAnnouncedAndLongHeadersAreNoReasonToRefuse(t *testing.T) {
 	t.Parallel()
 
-	s := startServeWAF(t, "", map[string]string{
-		requestMaxBytes:       "1",
-		clientHeaderMaxBytes:  "5K",
-		clientRequestTimeout:  off,
-		clientResponseTimeout: off,
-		trustedProxies:        localhost,
-	})
+	s := startServeWAF(t, "", nil)
 
 	req := s.questionWith(http.MethodPost, siteA, client, "/",
 		strings.NewReader("a body"))
-	req.Header.Set(proxy.ContentLengthHeader, "1073741824")
+	req.Header.Set(servewaf.ContentLengthHeader, "1073741824")
 	req.Header.Set(forwardedFor, otherClient)
 	req.Header.Set("X-Long", strings.Repeat("x", 40<<10))
 
 	got := do(t, req)
-	wantDisposition(t, got, http.StatusOK, proxy.DispositionAllow)
+	wantDisposition(t, got, http.StatusOK, servewaf.DispositionAllow)
 
 	line := s.out.requestLine(t)
 	if line.ClientIP != client || line.ContentLength != 1<<30 {
@@ -1493,33 +1473,23 @@ func TestSettingsOfTheLimitsAndTheProxiesAreIgnored(t *testing.T) {
 	}
 }
 
-func TestShortClientResponseTimeoutIsIgnored(t *testing.T) {
+func TestLogLevelHoldsBackNoRequestLine(t *testing.T) {
 	t.Parallel()
 
-	// The setting would leave no time to send any answer.
-	s := startServeWAF(t, "", map[string]string{
-		clientResponseTimeout: time.Nanosecond.String(), denyNets: client,
-	})
+	s := startServeWAF(t, "", map[string]string{"SWWAF_LOG_LEVEL": "error"})
 
-	wantDisposition(t, s.ask(client, "/"), http.StatusForbidden, proxy.DispositionDeny)
-	wantStatus(t, get(t, s.addr, proxy.HealthPath), http.StatusOK)
-}
+	// A refused question would write a process warning, held back at error.
+	req := s.question(siteA, client, "/")
+	req.Header.Del(requestIDHeader)
+	wantStatus(t, do(t, req), http.StatusBadRequest)
 
-func TestShortClientRequestTimeoutIsIgnored(t *testing.T) {
-	t.Parallel()
+	s.allowed(client)
+	wantLine(t, s.out.requestLine(t), http.StatusOK, requestlog.ActionForward)
 
-	// The setting would have run out while the Core Rule Set read the body. Go's
-	// server would then take the connection for gone, and the line say aborted.
-	s := startServeWAF(t, "", map[string]string{
-		clientRequestTimeout: time.Nanosecond.String(), wafMode: block, wafBodyLimit: "1M",
-	})
-
-	req := s.questionWith(http.MethodPost, siteA, client, "/", strings.NewReader("a=1"))
-	req.Header.Set("Content-Type", formData)
-	wantDisposition(t, do(t, req), http.StatusOK, proxy.DispositionAllow)
-
-	if line := s.out.requestLine(t); line.Aborted {
-		t.Errorf("log line says aborted: %+v", line.Line)
+	for _, line := range s.out.lines(t) {
+		if line["type"] == "process" {
+			t.Errorf("process line %v, want none at error", line)
+		}
 	}
 }
 
@@ -1562,7 +1532,7 @@ carried     header:Content-Length                block  ^6$
 			strings.NewReader("a body"))
 
 		if tc.announced != "" {
-			req.Header.Set(proxy.ContentLengthHeader, tc.announced)
+			req.Header.Set(servewaf.ContentLengthHeader, tc.announced)
 		}
 
 		wantStatus(t, do(t, req), tc.want)
@@ -1573,26 +1543,26 @@ func TestCoreRuleSetReadsTheBodyAQuestionCarries(t *testing.T) {
 	t.Parallel()
 
 	s := startServeWAF(t, "", map[string]string{
-		wafMode: block, wafBodyLimit: "1M",
+		wafMode: block, wafBodyLimit: "64K",
 	})
 
 	ask := func(contentType, body string) answer {
 		req := s.questionWith(http.MethodPost, siteA, client, "/",
 			strings.NewReader(body))
 		req.Header.Set("Content-Type", contentType)
-		req.Header.Set(proxy.ContentLengthHeader, "100000")
+		req.Header.Set(servewaf.ContentLengthHeader, "100000")
 
 		return do(t, req)
 	}
 
 	got := ask(formData, "id=1'%20OR%20'1'='1")
-	wantDisposition(t, got, http.StatusForbidden, proxy.DispositionDeny)
+	wantDisposition(t, got, http.StatusForbidden, servewaf.DispositionDeny)
 
 	// The first 64 KiB of a longer JSON body cannot be parsed, which is no
 	// attack, so the Core Rule Set does not read it.
-	cut := `{"text":"` + strings.Repeat("x", proxy.QuestionBodyMaxBytes)
-	got = ask("application/json", cut[:proxy.QuestionBodyMaxBytes])
-	wantDisposition(t, got, http.StatusOK, proxy.DispositionAllow)
+	cut := `{"text":"` + strings.Repeat("x", servewaf.QuestionBodyMaxBytes)
+	got = ask("application/json", cut[:servewaf.QuestionBodyMaxBytes])
+	wantDisposition(t, got, http.StatusOK, servewaf.DispositionAllow)
 }
 
 func TestCoreRuleSetAlertNamesTheSite(t *testing.T) {
@@ -1601,7 +1571,7 @@ func TestCoreRuleSetAlertNamesTheSite(t *testing.T) {
 	s := startServeWAF(t, "", map[string]string{wafMode: block})
 
 	got := s.ask(client, sqlInjection)
-	wantDisposition(t, got, http.StatusForbidden, proxy.DispositionDeny)
+	wantDisposition(t, got, http.StatusForbidden, servewaf.DispositionDeny)
 
 	waiting := s.queue.Snapshot().Waiting[alerts.DestinationWebhook]
 	if len(waiting) != 1 || waiting[0].Event != alerts.EventWAFBlock ||
@@ -1616,7 +1586,7 @@ func TestReputationHitAlertNamesTheSite(t *testing.T) {
 	s := startServeWAF(t, "", map[string]string{blocklistURLs: dropURL})
 	loadLists(t, s.server, map[string][]string{dropURL: {client}})
 
-	wantDisposition(t, s.ask(client, "/"), http.StatusForbidden, proxy.DispositionDeny)
+	wantDisposition(t, s.ask(client, "/"), http.StatusForbidden, servewaf.DispositionDeny)
 
 	waiting := s.queue.Snapshot().Waiting[alerts.DestinationWebhook]
 	if len(waiting) != 1 || waiting[0].Event != alerts.EventReputationHit ||

internal/servewaf/staticlists_test.go

@@ -1,4 +1,4 @@
-package proxy_test
+package servewaf_test
 
 import (
 	"net/http"
@@ -17,7 +17,7 @@ const (
 	unlistedAddr = "2001:db8::2"
 )
 
-func TestAllowNetsSkipEveryCheckButTheSizeLimit(t *testing.T) {
+func TestAllowNetsSkipEveryCheck(t *testing.T) {
 	t.Parallel()
 
 	var calls atomic.Int32
@@ -34,7 +34,6 @@ func TestAllowNetsSkipEveryCheckButTheSizeLimit(t *testing.T) {
 		denyNets:           fromKP,
 		deniedCountries:    "kp",
 		rateLimitPerMinute: "1",
-		requestMaxBytes:    "1K",
 	})
 
 	// Neither SWWAF_DENY_NETS, the country lists nor the limit of one
@@ -49,14 +48,6 @@ func TestAllowNetsSkipEveryCheckButTheSizeLimit(t *testing.T) {
 		t.Errorf("GeoJS was asked about %v, want nothing", asked())
 	}
 
-	// The size limit still applies.
-	body := strings.NewReader(strings.Repeat("a", 2<<10))
-	req := newRequest(t, http.MethodPost, addr, "/", body)
-	req.Header.Set(forwardedFor, fromKP)
-	wantStatus(t, do(t, req), http.StatusRequestEntityTooLarge)
-	wantLine(t, out.requestLines(t, 3)[2],
-		http.StatusRequestEntityTooLarge, requestlog.ActionTooLarge)
-
 	if calls.Load() != 2 {
 		t.Errorf("the app was called %d times, want 2", calls.Load())
 	}
@@ -82,7 +73,7 @@ func TestRequestFromAllowNetsIsNotCounted(t *testing.T) {
 	})
 }
 
-func TestDenyNetsRefuseBeforeTheLookupAndTheBody(t *testing.T) {
+func TestDenyNetsRefuseBeforeTheLookup(t *testing.T) {
 	t.Parallel()
 
 	var calls atomic.Int32
@@ -101,13 +92,9 @@ func TestDenyNetsRefuseBeforeTheLookupAndTheBody(t *testing.T) {
 	req.Header.Set(forwardedFor, fromDE)
 	wantStatus(t, do(t, req), http.StatusForbidden)
 
-	line := out.requestLine(t)
+	line := out.endedLine(t)
 	wantLine(t, line, http.StatusForbidden, requestlog.ActionDenied)
 
-	if line.RequestBytes != 0 {
-		t.Errorf("log line has request_bytes %d, want 0", line.RequestBytes)
-	}
-
 	if len(asked()) != 0 {
 		t.Errorf("GeoJS was asked about %v, want nothing", asked())
 	}
@@ -117,6 +104,15 @@ func TestDenyNetsRefuseBeforeTheLookupAndTheBody(t *testing.T) {
 	}
 }
 
+func TestDenyNetsRefusalNamesItsHeuristicAndNetblock(t *testing.T) {
+	t.Parallel()
+
+	s, _, _ := startWithClock(t, "", map[string]string{denyNets: clientsNet})
+
+	line := s.get(client, http.StatusForbidden, requestlog.ActionDenied)
+	wantHeuristic(t, line, "deny_nets", `{"netblock": "`+clientsNet+`"}`)
+}
+
 func TestRequestRefusedByDenyNetsIsNotCounted(t *testing.T) {
 	t.Parallel()
 
@@ -180,6 +176,6 @@ func wantAnswers(t *testing.T, addr string, out *output, requests []sentRequest)
 		req := newRequest(t, http.MethodGet, addr, "/", http.NoBody)
 		req.Header.Set(forwardedFor, sent.client)
 		wantStatus(t, do(t, req), sent.status)
-		wantLine(t, out.requestLines(t, i+1)[i], sent.status, sent.action)
+		wantLine(t, out.endedLines(t, i+1)[i], sent.status, sent.action)
 	}
 }

internal/servewaf/trappaths.go

@@ -0,0 +1,39 @@
+package servewaf
+
+// The heuristic trap_paths. It reads SWWAF_TRAP_PATHS.
+
+import (
+	"context"
+	"slices"
+	"time"
+
+	"sneak.berlin/go/smallwebwaf/internal/bans"
+	"sneak.berlin/go/smallwebwaf/internal/requestlog"
+	"sneak.berlin/go/smallwebwaf/internal/rules"
+)
+
+// trapPaths refuses a request for a path in SWWAF_TRAP_PATHS: its path as a
+// path rule sees it, without the query, as sent or once percent-decoded, is one
+// of them. Such a request is a clear sign of attack, as a ban rule's match is:
+// it bans the client's netblock, or in observe mode raises the alert for the
+// ban it would have made. The ban's notes give the path as sent, and so does
+// its figure.
+type trapPaths struct{}
+
+func (trapPaths) name() string { return "trap_paths" }
+
+func (trapPaths) check(_ context.Context, rq *request, now time.Time) *verdict {
+	path := rules.Path(rq.in)
+	if !slices.Contains(rq.h.config.TrapPaths, path) &&
+		!slices.Contains(rq.h.config.TrapPaths, rules.DecodeOnce(path)) {
+		return nil
+	}
+
+	rq.attack = true
+	rq.banForAttack(now, bans.Notes{TrapPath: path})
+
+	return &verdict{
+		action:  requestlog.ActionBanned,
+		figures: map[string]any{"path": path},
+	}
+}

internal/servewaf/trappaths_test.go

@@ -1,4 +1,4 @@
-package proxy_test
+package servewaf_test
 
 import (
 	"net/http"
@@ -83,6 +83,16 @@ func TestTrapPathBansAsABanRuleDoes(t *testing.T) {
 	}
 }
 
+func TestTrapPathRefusalNamesItsHeuristicAndPath(t *testing.T) {
+	t.Parallel()
+
+	s, _, _ := startWithClock(t, "", map[string]string{trapPaths: trapPathList})
+
+	line := s.request(client, "/wp-login.php?redirect_to=x", http.StatusForbidden,
+		requestlog.ActionBanned)
+	wantHeuristic(t, line, "trap_paths", `{"path": "/wp-login.php"}`)
+}
+
 func TestTrapPathMatchesThePathDecodedOnce(t *testing.T) {
 	t.Parallel()
 

internal/smallwebwaf/healthcheck.go

@@ -11,19 +11,22 @@ import (
 	"time"
 
 	"sneak.berlin/go/smallwebwaf/internal/config"
-	"sneak.berlin/go/smallwebwaf/internal/proxy"
+	"sneak.berlin/go/smallwebwaf/internal/servewaf"
 )
 
 // healthCheckTimeout bounds the whole health check.
 const healthCheckTimeout = 5 * time.Second
 
-var errHealthEndpoint = errors.New("smallwebwaf's health endpoint answered")
+var errHealthEndpoint = errors.New("the health endpoint answered")
 
-// HealthCheck is the container's health check. It returns 0 while
-// smallwebwaf answers its health endpoint on 127.0.0.1, at the port in
-// SWWAF_LISTEN_ADDR, and the app accepts connections at the address in
-// SWWAF_UPSTREAM_URL. Otherwise it writes why to stderr and returns 1.
-// It reads no other setting, nor a file that another names, so neither
+// HealthCheck is the container's health check. In servewaf's container, where
+// SMALLWEBWAF_COMMAND is servewaf, it returns 0 while servewaf answers its health
+// endpoint on 127.0.0.1, at the port in SWWAF_LISTEN_ADDR. In rproxy's container,
+// where SMALLWEBWAF_COMMAND is rproxy, unset or empty, it returns 0 while rproxy
+// answers its health endpoint on 127.0.0.1, at the port in SWRP_LISTEN_ADDR, and
+// the app accepts connections at the address in SWRP_UPSTREAM_URL. Otherwise,
+// any other value of SMALLWEBWAF_COMMAND included, it writes why to stderr and
+// returns 1. It reads no other setting, nor a file that another names, so neither
 // can fail it.
 // args are the arguments after `healthcheck`; it takes none, and given
 // one it names it on stderr and returns 1 without checking anything.
@@ -38,7 +41,20 @@ func HealthCheck(
 		return 1
 	}
 
-	err := healthCheck(ctx, lookupEnv)
+	ctx, cancel := context.WithTimeout(ctx, healthCheckTimeout)
+	defer cancel()
+
+	command, err := config.Command(lookupEnv)
+
+	switch {
+	case err != nil:
+		err = fmt.Errorf("invalid setting: %w", err)
+	case command == "servewaf":
+		err = checkServeWAF(ctx, lookupEnv)
+	default:
+		err = checkRProxyAndApp(ctx, lookupEnv)
+	}
+
 	if err != nil {
 		_, _ = fmt.Fprintln(stderr, "unhealthy:", err)
 
@@ -48,33 +64,33 @@ func HealthCheck(
 	return 0
 }
 
-func healthCheck(ctx context.Context, lookupEnv func(string) (string, bool)) error {
-	ctx, cancel := context.WithTimeout(ctx, healthCheckTimeout)
-	defer cancel()
-
-	listenAddr, upstreamURL, err := config.ListenAddrAndUpstreamURL(lookupEnv)
+// checkServeWAF asks servewaf's health endpoint.
+func checkServeWAF(ctx context.Context, lookupEnv func(string) (string, bool)) error {
+	listenAddr, err := config.ServeWAFListenAddr(lookupEnv)
 	if err != nil {
 		return fmt.Errorf("invalid setting: %w", err)
 	}
 
-	// The settings have checked that the address has a port.
-	_, port, _ := net.SplitHostPort(listenAddr)
-	health := "http://" + net.JoinHostPort("127.0.0.1", port) + proxy.HealthPath
-
-	req, err := http.NewRequestWithContext(ctx, http.MethodGet, health, http.NoBody)
+	err = askHealthEndpoint(ctx, listenAddr)
 	if err != nil {
-		return fmt.Errorf("make the request: %w", err)
+		return fmt.Errorf("ask servewaf: %w", err)
 	}
 
-	res, err := http.DefaultClient.Do(req)
+	return nil
+}
+
+// checkRProxyAndApp asks rproxy's health endpoint, and connects to the app.
+func checkRProxyAndApp(
+	ctx context.Context, lookupEnv func(string) (string, bool),
+) error {
+	listenAddr, upstreamURL, err := config.RProxyListenAddrAndUpstreamURL(lookupEnv)
 	if err != nil {
-		return fmt.Errorf("ask smallwebwaf: %w", err)
+		return fmt.Errorf("invalid setting: %w", err)
 	}
 
-	_ = res.Body.Close()
-
-	if res.StatusCode != http.StatusOK {
-		return fmt.Errorf("%w %s", errHealthEndpoint, res.Status)
+	err = askHealthEndpoint(ctx, listenAddr)
+	if err != nil {
+		return fmt.Errorf("ask rproxy: %w", err)
 	}
 
 	conn, err := (&net.Dialer{}).DialContext(ctx, "tcp", appAddress(upstreamURL))
@@ -87,6 +103,31 @@ func healthCheck(ctx context.Context, lookupEnv func(string) (string, bool)) err
 	return nil
 }
 
+// askHealthEndpoint asks the health endpoint on 127.0.0.1 at the port of
+// listenAddr, which the settings have checked has one.
+func askHealthEndpoint(ctx context.Context, listenAddr string) error {
+	_, port, _ := net.SplitHostPort(listenAddr)
+	health := "http://" + net.JoinHostPort("127.0.0.1", port) + servewaf.HealthPath
+
+	req, err := http.NewRequestWithContext(ctx, http.MethodGet, health, http.NoBody)
+	if err != nil {
+		return fmt.Errorf("make the request: %w", err)
+	}
+
+	res, err := http.DefaultClient.Do(req)
+	if err != nil {
+		return fmt.Errorf("send the request: %w", err)
+	}
+
+	_ = res.Body.Close()
+
+	if res.StatusCode != http.StatusOK {
+		return fmt.Errorf("%w %s", errHealthEndpoint, res.Status)
+	}
+
+	return nil
+}
+
 // appAddress is the host and port of the app's URL, the port being the
 // scheme's own when the URL names none.
 func appAddress(app *url.URL) string {

internal/smallwebwaf/healthcheck_test.go

@@ -15,11 +15,16 @@ import (
 	"sneak.berlin/go/smallwebwaf/internal/smallwebwaf"
 )
 
-func TestHealthCheck(t *testing.T) {
-	t.Parallel()
+const (
+	// commandSetting says which command a container runs, and which the health
+	// check checks.
+	commandSetting = "SMALLWEBWAF_COMMAND"
+	// serveWAFCommand is the command that runs servewaf.
+	serveWAFCommand = "servewaf"
+)
 
-	app := httptest.NewServer(http.NotFoundHandler())
-	defer app.Close()
+func TestHealthCheckInServeWAFsContainer(t *testing.T) {
+	t.Parallel()
 
 	ctx, stop := context.WithCancel(t.Context())
 	defer stop()
@@ -27,10 +32,9 @@ func TestHealthCheck(t *testing.T) {
 	out := &output{}
 	exited := make(chan int, 1)
 	settings := map[string]string{
-		listenAddr:  localhost + ":0",
-		upstreamURL: app.URL,
-		stateDir:    t.TempDir(),
-		rulesDir:    t.TempDir(),
+		listenAddr: localhost + ":0",
+		stateDir:   t.TempDir(),
+		rulesDir:   t.TempDir(),
 	}
 
 	go func() {
@@ -39,40 +43,36 @@ func TestHealthCheck(t *testing.T) {
 
 	addr, _ := out.line(t, "msg", "starting")["address"].(string)
 	_, port, _ := net.SplitHostPort(addr)
+
 	// The container's settings: an address to listen on with an empty
 	// host part, which the health check asks at 127.0.0.1.
-	env := map[string]string{listenAddr: ":" + port, upstreamURL: app.URL}
+	wantHealthCheck(t, map[string]string{
+		commandSetting: serveWAFCommand, listenAddr: ":" + port,
+	}, 0, "")
 
-	wantHealthCheck(t, env, 0, "")
-
-	// The health check reads those two settings alone, here given as
-	// files: a removed or invalid token file, or an invalid value of
-	// another setting, does not fail it.
+	// The health check reads that setting alone, here given as a file: a removed
+	// or invalid token file, or an invalid value of another setting, does not
+	// fail it.
 	for _, other := range []struct{ name, value string }{
 		{"SWWAF_METRICS_TOKEN_FILE", filepath.Join(t.TempDir(), "removed")},
 		{"SWWAF_METRICS_TOKEN_FILE", writeFile(t, "too short\n")},
 		{"SWWAF_MODE", "neither"},
 	} {
 		wantHealthCheck(t, map[string]string{
-			listenAddr + "_FILE":  writeFile(t, ":"+port+"\n"),
-			upstreamURL + "_FILE": writeFile(t, app.URL+"\n"),
-			other.name:            other.value,
+			commandSetting:       serveWAFCommand,
+			listenAddr + "_FILE": writeFile(t, ":"+port+"\n"),
+			other.name:           other.value,
 		}, 0, "")
 	}
 
-	// Another test can take a closed server's port at once, so the app's
-	// address here is a multicast address, to which TCP cannot connect.
-	wantHealthCheck(t, map[string]string{
-		listenAddr:  ":" + port,
-		upstreamURL: "http://224.0.0.1",
-	}, 1, "unhealthy: connect to the app: ")
-
 	// Listening on port 0 takes any free port, so nothing listens on port 0
 	// itself.
-	wantHealthCheck(t, map[string]string{listenAddr: ":0"}, 1,
-		"unhealthy: ask smallwebwaf: ")
-	wantHealthCheck(t, map[string]string{listenAddr: "8080"}, 1,
-		"unhealthy: invalid setting: SWWAF_LISTEN_ADDR: ")
+	wantHealthCheck(t, map[string]string{
+		commandSetting: serveWAFCommand, listenAddr: ":0",
+	}, 1, "unhealthy: ask servewaf: ")
+	wantHealthCheck(t, map[string]string{
+		commandSetting: serveWAFCommand, listenAddr: "8080",
+	}, 1, "unhealthy: invalid setting: SWWAF_LISTEN_ADDR: ")
 
 	stop()
 
@@ -83,6 +83,63 @@ func TestHealthCheck(t *testing.T) {
 	}
 }
 
+func TestHealthCheckInRProxysContainer(t *testing.T) {
+	t.Parallel()
+
+	app := httptest.NewServer(http.NotFoundHandler())
+	defer app.Close()
+
+	// Nothing listens at the backend. The health check asks rproxy and the app,
+	// whether or not servewaf answers.
+	site, _ := startRProxy(t, "http://127.0.0.1:9", app.URL)
+	_, port, _ := net.SplitHostPort(strings.TrimPrefix(site, "http://"))
+	settings := func(more ...string) map[string]string {
+		env := map[string]string{rproxyListenAddr: ":" + port, rproxyUpstreamURL: app.URL}
+		for i := 0; i < len(more); i += 2 {
+			env[more[i]] = more[i+1]
+		}
+
+		return env
+	}
+
+	wantHealthCheck(t, settings(), 0, "")
+	wantHealthCheck(t, settings(commandSetting, ""), 0, "")
+	wantHealthCheck(t, settings(commandSetting, "rproxy"), 0, "")
+
+	// SMALLWEBWAF_COMMAND cannot be given as a file.
+	wantHealthCheck(t, settings(commandSetting+"_FILE", writeFile(t, "servewaf\n")),
+		0, "")
+
+	// Another setting does not fail it, even an invalid one, and neither does
+	// SWRP_WAF_BACKEND being unset.
+	wantHealthCheck(t, settings("SWRP_TIMEOUT_MS", "soon"), 0, "")
+
+	// Another test can take a closed server's port at once, so the app's
+	// address here is a multicast address, to which TCP cannot connect.
+	wantHealthCheck(t, settings(rproxyUpstreamURL, "http://224.0.0.1"), 1,
+		"unhealthy: connect to the app: ")
+
+	// Listening on port 0 takes any free port, so nothing listens on port 0
+	// itself.
+	wantHealthCheck(t, settings(rproxyListenAddr, ":0"), 1, "unhealthy: ask rproxy: ")
+	wantHealthCheck(t, settings(rproxyListenAddr, "8080"), 1,
+		"unhealthy: invalid setting: SWRP_LISTEN_ADDR: ")
+
+	// No setting of rproxy's has a form given as a file.
+	wantHealthCheck(t, map[string]string{
+		rproxyListenAddr + "_FILE": writeFile(t, ":"+port+"\n"),
+		rproxyUpstreamURL:          app.URL,
+	}, 1, "unhealthy: ask rproxy: ")
+}
+
+func TestHealthCheckFailsWithAnyOtherCommand(t *testing.T) {
+	t.Parallel()
+
+	wantHealthCheck(t, map[string]string{commandSetting: "healthcheck"}, 1,
+		"unhealthy: invalid setting: SMALLWEBWAF_COMMAND: "+
+			"\"healthcheck\" is not rproxy or servewaf\n")
+}
+
 func TestHealthCheckRefusesAnArgument(t *testing.T) {
 	t.Parallel()
 

internal/smallwebwaf/rproxy_test.go

@@ -19,7 +19,7 @@ import (
 	"testing"
 	"time"
 
-	"sneak.berlin/go/smallwebwaf/internal/proxy"
+	"sneak.berlin/go/smallwebwaf/internal/servewaf"
 	"sneak.berlin/go/smallwebwaf/internal/smallwebwaf"
 )
 
@@ -28,6 +28,8 @@ const (
 	wafBackend = "SWRP_WAF_BACKEND"
 	// rproxyListenAddr is the setting that says where rproxy listens.
 	rproxyListenAddr = "SWRP_LISTEN_ADDR"
+	// rproxyUpstreamURL is the setting that says where the app is.
+	rproxyUpstreamURL = "SWRP_UPSTREAM_URL"
 	// rproxyTimeout is the setting that says how long rproxy waits for servewaf.
 	rproxyTimeout = "SWRP_TIMEOUT_MS"
 	// bannedProbe is a path the default rule file bans a client for.
@@ -100,7 +102,7 @@ func startServeWAF(t *testing.T, env map[string]string) (string, *output, func()
 	exited := make(chan int, 1)
 
 	go func() {
-		exited <- runAs(ctx, true, env, out)
+		exited <- run(ctx, env, out)
 	}()
 
 	addr, _ := out.line(t, "msg", "starting")["address"].(string)
@@ -151,7 +153,7 @@ func TestABanThroughOneSiteRefusesTheClientOnTheOther(t *testing.T) {
 
 	// One request's three lines carry one id, rproxy's with servewaf's answer.
 	line := firstOut.line(t, "path", bannedProbe)
-	if line["disposition"] != proxy.DispositionDeny || line["client_ip"] != placed {
+	if line["disposition"] != servewaf.DispositionDeny || line["client_ip"] != placed {
 		t.Errorf("rproxy's line is %v", line)
 	}
 
@@ -223,7 +225,7 @@ func TestTheSiteAnswersWhileServeWAFIsStoppedAndStartedAgain(t *testing.T) {
 	wantStatus(t, site+"/after-stop", placed, http.StatusOK)
 
 	line := out.line(t, "path", "/after-stop")
-	if line["disposition"] != proxy.DispositionAllow ||
+	if line["disposition"] != servewaf.DispositionAllow ||
 		line["default_disposition"] != true {
 		t.Errorf("rproxy's line is %v", line)
 	}
@@ -316,7 +318,7 @@ func TestAChunkedBodyStaysABodyAtServeWAF(t *testing.T) {
 	const smuggledID = "smuggled-request"
 
 	smuggled := "GET " + bannedProbe + " HTTP/1.1\r\nHost: site.example\r\n" +
-		proxy.ClientHeader + ": " + otherClient + "\r\n" +
+		servewaf.ClientHeader + ": " + otherClient + "\r\n" +
 		"X-Request-ID: " + smuggledID + "\r\n\r\n"
 
 	status := sendRaw(t, site, "POST /upload HTTP/1.1\r\nHost: site.example\r\n"+
@@ -457,10 +459,10 @@ func TestRProxyAsksAServeWAFThatSpeaksHTTP2OverHTTP1(t *testing.T) {
 	protocols := make(chan string, 10)
 	backend := httptest.NewUnstartedServer(http.HandlerFunc(
 		func(w http.ResponseWriter, r *http.Request) {
-			if r.Header.Get(proxy.ClientHeader) != "" {
+			if r.Header.Get(servewaf.ClientHeader) != "" {
 				protocols <- r.Proto
 
-				w.Header().Set(proxy.DispositionHeader, proxy.DispositionDeny)
+				w.Header().Set(servewaf.DispositionHeader, servewaf.DispositionDeny)
 				w.WriteHeader(http.StatusForbidden)
 			}
 		}))
@@ -530,8 +532,8 @@ func TestRProxyStoppingWaitsForAReportBeingSent(t *testing.T) {
 	release := make(chan struct{})
 	backend := httptest.NewServer(http.HandlerFunc(
 		func(w http.ResponseWriter, r *http.Request) {
-			if r.Header.Get(proxy.ClientHeader) != "" {
-				w.Header().Set(proxy.DispositionHeader, proxy.DispositionAllow)
+			if r.Header.Get(servewaf.ClientHeader) != "" {
+				w.Header().Set(servewaf.DispositionHeader, servewaf.DispositionAllow)
 
 				return
 			}
@@ -638,7 +640,7 @@ func TestRProxyStoppingCutsOffARequestAfterFiveSeconds(t *testing.T) {
 
 	backend := httptest.NewServer(http.HandlerFunc(
 		func(w http.ResponseWriter, _ *http.Request) {
-			w.Header().Set(proxy.DispositionHeader, proxy.DispositionAllow)
+			w.Header().Set(servewaf.DispositionHeader, servewaf.DispositionAllow)
 		}))
 	t.Cleanup(backend.Close)
 
@@ -755,7 +757,7 @@ func TestMainRunsRProxy(t *testing.T) {
 	addr, cmd, out := startRProxyProcess(t, wafBackend+"=http://127.0.0.1:9")
 
 	req, err := http.NewRequestWithContext(t.Context(), http.MethodGet,
-		"http://"+addr+proxy.HealthPath, http.NoBody)
+		"http://"+addr+servewaf.HealthPath, http.NoBody)
 	if err != nil {
 		t.Fatalf("new request: %v", err)
 	}

internal/smallwebwaf/servewaf_test.go

@@ -1,6 +1,7 @@
 package smallwebwaf_test
 
 import (
+	"bytes"
 	"context"
 	"crypto/rand"
 	"io"
@@ -13,7 +14,7 @@ import (
 	"testing"
 	"time"
 
-	"sneak.berlin/go/smallwebwaf/internal/proxy"
+	"sneak.berlin/go/smallwebwaf/internal/servewaf"
 	"sneak.berlin/go/smallwebwaf/internal/smallwebwaf"
 )
 
@@ -33,59 +34,88 @@ func TestMain(m *testing.M) {
 	os.Exit(smallwebwaf.Main(testVersion))
 }
 
-func TestMainAnswersQuestionsOnlyAsServeWAF(t *testing.T) {
+func TestMainRunsServeWAF(t *testing.T) {
 	t.Parallel()
 
-	for _, tc := range []struct {
-		command, disposition string
-	}{
-		{"servewaf", proxy.DispositionAllow},
-		{"", ""},
-	} {
-		t.Run("command "+tc.command, func(t *testing.T) {
+	binary, err := os.Executable()
+	if err != nil {
+		t.Fatalf("find the test binary: %v", err)
+	}
+
+	ctx, cancel := context.WithTimeout(t.Context(), 3*waitLimit)
+	defer cancel()
+
+	out := &output{}
+	cmd := exec.CommandContext(ctx, binary) //nolint:gosec // this test binary
+	cmd.Stdout = out
+
+	cmd.Env = append(os.Environ(),
+		commandForMain+"="+serveWAFCommand,
+		listenAddr+"="+localhost+":0",
+		stateDir+"="+t.TempDir(),
+		rulesDir+"="+t.TempDir(),
+		lookupSource+"=off")
+
+	err = cmd.Start()
+	if err != nil {
+		t.Fatalf("start: %v", err)
+	}
+
+	t.Cleanup(func() {
+		_ = cmd.Process.Kill()
+		_ = cmd.Wait()
+	})
+
+	addr, _ := out.line(t, "msg", "starting")["address"].(string)
+	ask(t, addr, "/", http.StatusOK, servewaf.DispositionAllow)
+
+	err = cmd.Process.Signal(syscall.SIGTERM)
+	if err != nil {
+		t.Fatalf("signal: %v", err)
+	}
+
+	err = cmd.Wait()
+	if err != nil {
+		t.Errorf("exit: %v; output:\n%s", err, out.text())
+	}
+}
+
+func TestMainWithoutACommandItKnowsPrintsTheCommands(t *testing.T) {
+	t.Parallel()
+
+	binary, err := os.Executable()
+	if err != nil {
+		t.Fatalf("find the test binary: %v", err)
+	}
+
+	for _, command := range []string{"", "serve"} {
+		t.Run("command "+command, func(t *testing.T) {
 			t.Parallel()
 
-			binary, err := os.Executable()
-			if err != nil {
-				t.Fatalf("find the test binary: %v", err)
-			}
-
-			ctx, cancel := context.WithTimeout(t.Context(), 3*waitLimit)
+			ctx, cancel := context.WithTimeout(t.Context(), waitLimit)
 			defer cancel()
 
-			out := &output{}
-			cmd := exec.CommandContext(ctx, binary) //nolint:gosec // this test binary
-			cmd.Stdout = out
+			var stdout, stderr bytes.Buffer
 
-			cmd.Env = append(os.Environ(),
-				commandForMain+"="+tc.command,
-				listenAddr+"="+localhost+":0",
-				upstreamURL+"="+startApp(t),
-				stateDir+"="+t.TempDir(),
-				rulesDir+"="+t.TempDir(),
-				lookupSource+"=off")
+			cmd := exec.CommandContext(ctx, binary)
+			cmd.Stdout, cmd.Stderr = &stdout, &stderr
 
-			err = cmd.Start()
-			if err != nil {
-				t.Fatalf("start: %v", err)
+			cmd.Env = append(os.Environ(), commandForMain+"="+command)
+
+			err := cmd.Run()
+
+			if code := cmd.ProcessState.ExitCode(); code != 2 {
+				t.Errorf("exit status %d (%v), want 2", code, err)
 			}
 
-			t.Cleanup(func() {
-				_ = cmd.Process.Kill()
-				_ = cmd.Wait()
-			})
-
-			addr, _ := out.line(t, "msg", "starting")["address"].(string)
-			ask(t, addr, "/", http.StatusOK, tc.disposition)
-
-			err = cmd.Process.Signal(syscall.SIGTERM)
-			if err != nil {
-				t.Fatalf("signal: %v", err)
+			for _, name := range []string{"rproxy", serveWAFCommand, "healthcheck"} {
+				if !strings.Contains(stderr.String(), name) {
+					t.Errorf("stderr %q does not name %s", stderr.String(), name)
+				}
 			}
 
-			err = cmd.Wait()
-			if err != nil {
-				t.Errorf("exit: %v; output:\n%s", err, out.text())
+			if stdout.Len() != 0 {
+				t.Errorf("stdout %q, want nothing", stdout.String())
 			}
 		})
 	}
@@ -102,7 +132,7 @@ func ask(t *testing.T, addr, path string, status int, disposition string) {
 		t.Fatalf("new request: %v", err)
 	}
 
-	req.Header.Set(proxy.ClientHeader, placed)
+	req.Header.Set(servewaf.ClientHeader, placed)
 	req.Header.Set("X-Request-ID", rand.Text())
 
 	transport := &http.Transport{}
@@ -117,9 +147,9 @@ func ask(t *testing.T, addr, path string, status int, disposition string) {
 	_ = res.Body.Close()
 
 	if res.StatusCode != status ||
-		res.Header.Get(proxy.DispositionHeader) != disposition {
+		res.Header.Get(servewaf.DispositionHeader) != disposition {
 		t.Errorf("answered %d with disposition %q, want %d with %q", res.StatusCode,
-			res.Header.Get(proxy.DispositionHeader), status, disposition)
+			res.Header.Get(servewaf.DispositionHeader), status, disposition)
 	}
 }
 
@@ -134,7 +164,7 @@ func runServeWAF(t *testing.T, env map[string]string, use func(addr string)) {
 	exited := make(chan int, 1)
 
 	go func() {
-		exited <- runAs(ctx, true, env, out)
+		exited <- run(ctx, env, out)
 	}()
 
 	addr, _ := out.line(t, "msg", "starting")["address"].(string)
@@ -163,48 +193,12 @@ func TestServeWAFKeepsItsBansAcrossARestartAndNeedsNoApp(t *testing.T) {
 	}
 
 	runServeWAF(t, env, func(addr string) {
-		ask(t, addr, "/", http.StatusOK, proxy.DispositionAllow)
+		ask(t, addr, "/", http.StatusOK, servewaf.DispositionAllow)
 		// The default rule file bans a probe for this.
-		ask(t, addr, "/.env", http.StatusForbidden, proxy.DispositionDeny)
+		ask(t, addr, "/.env", http.StatusForbidden, servewaf.DispositionDeny)
 	})
 
 	runServeWAF(t, env, func(addr string) {
-		ask(t, addr, "/", http.StatusForbidden, proxy.DispositionDeny)
-	})
-}
-
-func TestWithoutACommandTheClientHeaderIsNoQuestion(t *testing.T) {
-	t.Parallel()
-
-	runUntilStopped(t, map[string]string{
-		listenAddr:  localhost + ":0",
-		upstreamURL: startApp(t),
-		stateDir:    t.TempDir(),
-		rulesDir:    t.TempDir(),
-	}, func(url string) {
-		req, err := http.NewRequestWithContext(t.Context(), http.MethodGet, url,
-			http.NoBody)
-		if err != nil {
-			t.Fatalf("new request: %v", err)
-		}
-
-		req.Header.Set(proxy.ClientHeader, placed)
-
-		transport := &http.Transport{}
-		defer transport.CloseIdleConnections()
-
-		res, err := (&http.Client{Transport: transport}).Do(req)
-		if err != nil {
-			t.Fatalf("request: %v", err)
-		}
-
-		body, err := io.ReadAll(res.Body)
-		_ = res.Body.Close()
-
-		if err != nil || string(body) != greeting ||
-			res.Header.Get(proxy.DispositionHeader) != "" {
-			t.Errorf("answered %q (%v) with disposition %q, want the app's greeting",
-				body, err, res.Header.Get(proxy.DispositionHeader))
-		}
+		ask(t, addr, "/", http.StatusForbidden, servewaf.DispositionDeny)
 	})
 }

internal/smallwebwaf/smallwebwaf.go

@@ -1,15 +1,16 @@
-// Package smallwebwaf runs the smallwebwaf process: it reads the settings,
-// the rule files, the lookup database and the state files, serves requests
-// until it is told to stop, and then stops in an orderly way, writing the
-// state files. It serves them in front of an app, or, as `smallwebwaf
-// servewaf`, by answering rproxy's questions about them. As `smallwebwaf
-// rproxy`, it instead reads rproxy's settings alone, and runs the reverse proxy
-// in front of one app that asks servewaf about each request.
+// Package smallwebwaf runs the smallwebwaf process, as the command it is given.
+// `smallwebwaf servewaf` reads the settings, the rule files, the lookup database
+// and the state files, answers rproxy's questions until it is told to stop, and
+// then stops in an orderly way, writing the state files. `smallwebwaf rproxy`
+// reads rproxy's settings alone, and runs the reverse proxy in front of one app
+// that asks servewaf about each request. `smallwebwaf healthcheck` is the
+// container's health check.
 package smallwebwaf
 
 import (
 	"context"
 	"errors"
+	"fmt"
 	"io"
 	"log/slog"
 	"net"
@@ -22,11 +23,11 @@ import (
 	"sneak.berlin/go/smallwebwaf/internal/alerts"
 	"sneak.berlin/go/smallwebwaf/internal/config"
 	"sneak.berlin/go/smallwebwaf/internal/lookup"
-	"sneak.berlin/go/smallwebwaf/internal/proxy"
 	"sneak.berlin/go/smallwebwaf/internal/remotelog"
 	"sneak.berlin/go/smallwebwaf/internal/reputation"
 	"sneak.berlin/go/smallwebwaf/internal/requestlog"
 	"sneak.berlin/go/smallwebwaf/internal/rules"
+	"sneak.berlin/go/smallwebwaf/internal/servewaf"
 	"sneak.berlin/go/smallwebwaf/internal/state"
 )
 
@@ -35,12 +36,25 @@ import (
 // runit and docker wait a little longer before they kill the process.
 const shutdownTimeout = 5 * time.Second
 
-// remoteLogStopTimeout is how long, as smallwebwaf stops, the log lines
-// still waiting are sent to SWWAF_LOG_REMOTE_URL before they are given
-// up. stdout has carried them.
+// remoteLogStopTimeout is how long, as servewaf stops, the log lines still
+// waiting are sent to SWWAF_LOG_REMOTE_URL before they are given up. stdout has
+// carried them.
 const remoteLogStopTimeout = 2 * time.Second
 
-// Params are what Run needs from the process.
+// usageStatus is the exit status with no command, or one smallwebwaf does not
+// know.
+const usageStatus = 2
+
+// usage is what smallwebwaf prints then.
+const usage = `usage: smallwebwaf <command>
+
+commands:
+  rproxy       the reverse proxy in front of one app
+  servewaf     decides for rproxy, and keeps bans, counters and history
+  healthcheck  the container's health check
+`
+
+// Params are what RunServeWAF and RunRProxy need from the process.
 type Params struct {
 	// Version is the version of the binary, set when it is built.
 	Version string
@@ -48,44 +62,47 @@ type Params struct {
 	LookupEnv func(string) (string, bool)
 	// Stdout receives the request log and the process's own messages.
 	Stdout io.Writer
-	// ServeWAF makes it `smallwebwaf servewaf`, which answers rproxy's
-	// questions, rather than the proxy in front of an app.
-	ServeWAF bool
 }
 
-// Main runs smallwebwaf until SIGTERM or SIGINT, and returns the
-// process's exit status. Run as `smallwebwaf servewaf`, it answers
-// rproxy's questions rather than pass requests to an app. Run as
-// `smallwebwaf rproxy`, it is the reverse proxy that asks those questions.
-// Run as `smallwebwaf healthcheck`, it is the container's health check
-// instead.
+// Main runs the command os.Args names, and returns the process's exit status.
+// `smallwebwaf rproxy` and `smallwebwaf servewaf` run until SIGTERM or SIGINT.
+// With no command, or one it does not know, it prints the commands and returns
+// usageStatus.
 func Main(version string) int {
-	if len(os.Args) > 1 && os.Args[1] == "healthcheck" {
-		return HealthCheck(context.Background(), os.Args[2:], os.LookupEnv, os.Stderr)
+	args := os.Args[1:]
+	if len(args) == 0 {
+		return printUsage(os.Stderr)
 	}
 
 	ctx, stop := signal.NotifyContext(context.Background(),
 		syscall.SIGTERM, os.Interrupt)
 	defer stop()
 
-	params := Params{
-		Version:   version,
-		LookupEnv: os.LookupEnv,
-		Stdout:    os.Stdout,
-		ServeWAF:  len(os.Args) > 1 && os.Args[1] == "servewaf",
-	}
+	params := Params{Version: version, LookupEnv: os.LookupEnv, Stdout: os.Stdout}
 
-	if len(os.Args) > 1 && os.Args[1] == "rproxy" {
+	switch args[0] {
+	case "rproxy":
 		return RunRProxy(ctx, params)
+	case "servewaf":
+		return RunServeWAF(ctx, params)
+	case "healthcheck":
+		return HealthCheck(ctx, args[1:], os.LookupEnv, os.Stderr)
+	default:
+		return printUsage(os.Stderr)
 	}
-
-	return Run(ctx, params)
 }
 
-// Run reads the settings, the rule files, the lookup database and the
-// state files, then serves requests until ctx is done. It returns the
-// process's exit status, 1 when smallwebwaf cannot start.
-func Run(ctx context.Context, params Params) int {
+// printUsage writes the commands to w, and returns usageStatus.
+func printUsage(w io.Writer) int {
+	_, _ = fmt.Fprint(w, usage)
+
+	return usageStatus
+}
+
+// RunServeWAF is `smallwebwaf servewaf`: it reads the settings, the rule files,
+// the lookup database and the state files, then serves requests until ctx is
+// done. It returns the process's exit status, 1 when servewaf cannot start.
+func RunServeWAF(ctx context.Context, params Params) int {
 	// Until the settings are read, the one message is an invalid setting's
 	// error, which every SWWAF_LOG_LEVEL lets through.
 	processLog := requestlog.NewProcessLogger(params.Stdout,
@@ -133,12 +150,7 @@ func Run(ctx context.Context, params Params) int {
 		return 1
 	}
 
-	newProxy := proxy.New
-	if params.ServeWAF {
-		newProxy = proxy.NewServeWAF
-	}
-
-	server, err := newServer(newProxy, cfg, stdout, processLog, now, ruleFiles, alertQueue)
+	server, err := newServer(cfg, stdout, processLog, now, ruleFiles, alertQueue)
 	if err != nil {
 		processLog.Error("cannot use the lookup database", "error", err.Error())
 
@@ -172,15 +184,13 @@ func Run(ctx context.Context, params Params) int {
 	return serve(ctx, server, listener, files, ruleFiles, alertQueue, processLog)
 }
 
-// newServer returns the server smallwebwaf runs, which newProxy makes, with
-// the metrics of the alerts, after reading the lookup database while
-// SWWAF_LOOKUP_SOURCE is file. A lookup database that cannot be read is an
-// error.
+// newServer returns the server servewaf runs, with the metrics of the alerts,
+// after reading the lookup database while SWWAF_LOOKUP_SOURCE is file. A lookup
+// database that cannot be read is an error.
 func newServer(
-	newProxy func(proxy.Params) *proxy.Server,
 	cfg *config.Config, stdout io.Writer, processLog *slog.Logger,
 	now func() time.Time, ruleFiles *rules.Files, alertQueue *alerts.Queue,
-) (*proxy.Server, error) {
+) (*servewaf.Server, error) {
 	var lookupFile *lookup.File
 
 	if cfg.LookupSource == "file" {
@@ -197,7 +207,7 @@ func newServer(
 		}
 	}
 
-	server := newProxy(proxy.Params{
+	server := servewaf.New(servewaf.Params{
 		Config:       cfg,
 		RequestLog:   stdout,
 		ProcessLog:   processLog,
@@ -220,7 +230,7 @@ func newServer(
 // loadStateFiles reads the state files into the parts of server and into
 // alertQueue, as state.Load does.
 func loadStateFiles(
-	cfg *config.Config, server *proxy.Server, alertQueue *alerts.Queue,
+	cfg *config.Config, server *servewaf.Server, alertQueue *alerts.Queue,
 	now func() time.Time, processLog *slog.Logger,
 ) (*state.Files, error) {
 	return state.Load(state.Params{
@@ -306,7 +316,7 @@ func startSending(
 // shutdownTimeout to finish, and writes every state file, alerts.json with
 // the alerts still waiting.
 func serve(
-	ctx context.Context, server *proxy.Server, listener net.Listener,
+	ctx context.Context, server *servewaf.Server, listener net.Listener,
 	files *state.Files, ruleFiles *rules.Files, alertQueue *alerts.Queue,
 	processLog *slog.Logger,
 ) int {
@@ -361,12 +371,10 @@ func serve(
 
 	// Run and Watch have ended, so nothing else reads or writes the
 	// files, and no alert is being sent, so that alerts.json keeps every
-	// alert not yet sent. Every request has ended too, but for two kinds
-	// that Go's server does not wait for: one cut off because Shutdown
-	// timed out, and one whose connection switched protocols, such as a
-	// WebSocket. Such a request adds to its client's history only as it
-	// ends, which can be after this write, and then that request is
-	// missing from clients.json.
+	// alert not yet sent. Every request has ended too, but for one cut off
+	// because Shutdown timed out, which adds to its client's history only as
+	// it ends. That can be after this write, and then that request is missing
+	// from clients.json.
 	<-written
 	<-watched
 	<-rulesWatched

internal/smallwebwaf/smallwebwaf_test.go

@@ -3,6 +3,7 @@ package smallwebwaf_test
 import (
 	"bytes"
 	"context"
+	"crypto/rand"
 	"encoding/json"
 	"io"
 	"net"
@@ -19,6 +20,7 @@ import (
 	"time"
 
 	"sneak.berlin/go/smallwebwaf/internal/lookup/lookuptest"
+	"sneak.berlin/go/smallwebwaf/internal/servewaf"
 	"sneak.berlin/go/smallwebwaf/internal/smallwebwaf"
 )
 
@@ -32,8 +34,6 @@ const (
 	// localhost is where the tests listen.
 	localhost            = "127.0.0.1"
 	listenAddr           = "SWWAF_LISTEN_ADDR"
-	upstreamURL          = "SWWAF_UPSTREAM_URL"
-	trustedProxies       = "SWWAF_TRUSTED_PROXIES"
 	stateDir             = "SWWAF_STATE_DIR"
 	stateWriteDelay      = "SWWAF_STATE_WRITE_DELAY"
 	stateCounterInterval = "SWWAF_STATE_COUNTER_INTERVAL"
@@ -122,18 +122,11 @@ func (o *output) text() string {
 	return o.buf.String()
 }
 
-// run runs smallwebwaf with the settings in env until ctx is done, and
-// returns its exit status. SWWAF_LOOKUP_SOURCE is off unless env sets it,
+// run runs `smallwebwaf servewaf` with the settings in env until ctx is done,
+// and returns its exit status. SWWAF_LOOKUP_SOURCE is off unless env sets it,
 // so that no test sends GeoJS its clients' addresses.
 func run(ctx context.Context, env map[string]string, out *output) int {
-	return runAs(ctx, false, env, out)
-}
-
-// runAs is run as `smallwebwaf servewaf` while serveWAF is true.
-func runAs(
-	ctx context.Context, serveWAF bool, env map[string]string, out *output,
-) int {
-	return smallwebwaf.Run(ctx, smallwebwaf.Params{
+	return smallwebwaf.RunServeWAF(ctx, smallwebwaf.Params{
 		Version: testVersion,
 		LookupEnv: func(name string) (string, bool) {
 			value, ok := env[name]
@@ -143,8 +136,7 @@ func runAs(
 
 			return value, ok
 		},
-		Stdout:   out,
-		ServeWAF: serveWAF,
+		Stdout: out,
 	})
 }
 
@@ -154,8 +146,8 @@ func TestInvalidSettingStopsTheStart(t *testing.T) {
 	out := &output{}
 
 	status := run(t.Context(), map[string]string{
-		"SWWAF_REQUEST_MAX_BYTES": "lots",
-		instanceName:              instance,
+		"SWWAF_BYTES_LIMIT_PER_MINUTE": "lots",
+		instanceName:                   instance,
 	}, out)
 	if status != 1 {
 		t.Errorf("exit status %d, want 1", status)
@@ -166,7 +158,7 @@ func TestInvalidSettingStopsTheStart(t *testing.T) {
 
 	if line["type"] != "process" || line["instance"] != instance ||
 		line["level"] != "ERROR" ||
-		!strings.HasPrefix(message, "SWWAF_REQUEST_MAX_BYTES: ") {
+		!strings.HasPrefix(message, "SWWAF_BYTES_LIMIT_PER_MINUTE: ") {
 		t.Errorf("start refused with %v", line)
 	}
 }
@@ -228,7 +220,6 @@ func TestAddressInUseStopsTheStart(t *testing.T) {
 func TestServesUntilToldToStop(t *testing.T) {
 	t.Parallel()
 
-	appURL := startApp(t)
 	dir := t.TempDir()
 
 	ctx, stop := context.WithCancel(t.Context())
@@ -237,10 +228,9 @@ func TestServesUntilToldToStop(t *testing.T) {
 
 	go func() {
 		exited <- run(ctx, map[string]string{
-			listenAddr:  localhost + ":0",
-			upstreamURL: appURL,
-			stateDir:    dir,
-			rulesDir:    filepath.Join("..", "..", "share", "rules.d"),
+			listenAddr: localhost + ":0",
+			stateDir:   dir,
+			rulesDir:   filepath.Join("..", "..", "share", "rules.d"),
 		}, out)
 	}()
 
@@ -250,10 +240,10 @@ func TestServesUntilToldToStop(t *testing.T) {
 	}
 
 	starting := out.line(t, "msg", "starting")
-	wantStartingLine(t, starting, appURL, dir)
+	wantStartingLine(t, starting, dir)
 
 	addr, _ := starting["address"].(string)
-	wantGreeting(t, "http://"+addr+"/")
+	wantAllowed(t, "http://"+addr+"/")
 	out.line(t, "type", "request")
 
 	stop()
@@ -325,7 +315,6 @@ func TestEveryLogLineAndMetricCarriesTheInstanceName(t *testing.T) {
 
 	env := map[string]string{
 		listenAddr:   localhost + ":0",
-		upstreamURL:  startApp(t),
 		stateDir:     t.TempDir(),
 		rulesDir:     t.TempDir(),
 		metricsToken: token,
@@ -363,7 +352,6 @@ func TestStateKeptAcrossRestarts(t *testing.T) {
 
 	env := map[string]string{
 		listenAddr:      localhost + ":0",
-		upstreamURL:     startApp(t),
 		stateDir:        t.TempDir(),
 		rulesDir:        t.TempDir(),
 		rateLimitPerDay: "2",
@@ -375,8 +363,8 @@ func TestStateKeptAcrossRestarts(t *testing.T) {
 
 	// The two requests a day allows, and a stop.
 	runUntilStopped(t, env, func(url string) {
-		wantGreeting(t, url)
-		wantGreeting(t, url)
+		wantAllowed(t, url)
+		wantAllowed(t, url)
 	})
 
 	// After a restart the client has no fresh allowance: its third
@@ -400,10 +388,8 @@ func TestBanRefusesItsNetblockAfterARestartWithAnotherScope(t *testing.T) {
 
 	env := map[string]string{
 		listenAddr:      localhost + ":0",
-		upstreamURL:     startApp(t),
 		stateDir:        t.TempDir(),
 		rulesDir:        t.TempDir(),
-		trustedProxies:  localhost + "/32",
 		rateLimitPerDay: "1",
 		scope:           "24",
 	}
@@ -447,11 +433,9 @@ func TestBanAddedAndLiftedByEditingBansJSON(t *testing.T) {
 
 	dir := t.TempDir()
 	env := map[string]string{
-		listenAddr:     localhost + ":0",
-		upstreamURL:    startApp(t),
-		stateDir:       dir,
-		rulesDir:       t.TempDir(),
-		trustedProxies: localhost + "/32",
+		listenAddr: localhost + ":0",
+		stateDir:   dir,
+		rulesDir:   t.TempDir(),
 		// No write comes due in the test, so only the watch on the
 		// directory can take the edits in.
 		stateWriteDelay:      "1h",
@@ -472,12 +456,10 @@ func TestBanAddedAndLiftedThroughTheEndpointsKeptInBansJSON(t *testing.T) {
 
 	dir := t.TempDir()
 	env := map[string]string{
-		listenAddr:     localhost + ":0",
-		upstreamURL:    startApp(t),
-		stateDir:       dir,
-		rulesDir:       t.TempDir(),
-		trustedProxies: localhost + "/32",
-		adminToken:     adminSecret,
+		listenAddr: localhost + ":0",
+		stateDir:   dir,
+		rulesDir:   t.TempDir(),
+		adminToken: adminSecret,
 		// Neither comes due in the test: the files are written as
 		// smallwebwaf stops.
 		stateWriteDelay:      "1h",
@@ -517,17 +499,16 @@ func TestRuleFileAddedWhileRunningTakesEffect(t *testing.T) {
 
 	dir := t.TempDir()
 	env := map[string]string{
-		listenAddr:  localhost + ":0",
-		upstreamURL: startApp(t),
-		stateDir:    t.TempDir(),
-		rulesDir:    dir,
+		listenAddr: localhost + ":0",
+		stateDir:   t.TempDir(),
+		rulesDir:   dir,
 		// The requests sent until the rule takes effect must not break a
 		// rate limit, whose ban would refuse them too.
 		"SWWAF_RATE_LIMIT_PER_MINUTE": "off",
 	}
 
 	out := runUntilStopped(t, env, func(url string) {
-		wantGreeting(t, url)
+		wantAllowed(t, url)
 
 		// Written once: each change would start the rule files' wait
 		// again. A file written before smallwebwaf watches the directory is
@@ -580,10 +561,8 @@ func TestLookupDatabaseReplacedWhileRunningTakesEffect(t *testing.T) {
 
 	env := map[string]string{
 		listenAddr:               localhost + ":0",
-		upstreamURL:              startApp(t),
 		stateDir:                 t.TempDir(),
 		rulesDir:                 t.TempDir(),
-		trustedProxies:           localhost + "/32",
 		metricsToken:             token,
 		instanceName:             instance,
 		lookupSource:             "file",
@@ -679,10 +658,8 @@ func TestBlocklistTriesAndCopiesKeptInReputationJSONAcrossRestarts(t *testing.T)
 	dir := t.TempDir()
 	env := map[string]string{
 		listenAddr:             localhost + ":0",
-		upstreamURL:            startApp(t),
 		stateDir:               dir,
 		rulesDir:               t.TempDir(),
-		trustedProxies:         localhost + "/32",
 		metricsToken:           token,
 		instanceName:           instance,
 		"SWWAF_BLOCKLIST_URLS": torURL,
@@ -763,10 +740,8 @@ func TestCrowdSecDecisionListKeptInReputationJSONAcrossARestart(t *testing.T) {
 	dir := t.TempDir()
 	env := map[string]string{
 		listenAddr:                localhost + ":0",
-		upstreamURL:               startApp(t),
 		stateDir:                  dir,
 		rulesDir:                  t.TempDir(),
-		trustedProxies:            localhost + "/32",
 		"SWWAF_CROWDSEC_LAPI_URL": engine.URL,
 		"SWWAF_CROWDSEC_LAPI_KEY": bouncerKey,
 	}
@@ -864,14 +839,13 @@ func TestEveryLineIsAlsoSentToTheRemoteLogEndpoint(t *testing.T) {
 
 	env := map[string]string{
 		listenAddr:             localhost + ":0",
-		upstreamURL:            startApp(t),
 		stateDir:               t.TempDir(),
 		rulesDir:               t.TempDir(),
 		"SWWAF_LOG_REMOTE_URL": "syslog+tcp://" + endpoint.Addr().String(),
 	}
 
 	out := runUntilStopped(t, env, func(url string) {
-		wantGreeting(t, url)
+		wantAllowed(t, url)
 	})
 	out.line(t, "type", "request")
 
@@ -920,7 +894,6 @@ func TestStalledRemoteLogEndpointHoldsUpNoRequest(t *testing.T) {
 
 	env := map[string]string{
 		listenAddr:                localhost + ":0",
-		upstreamURL:               startApp(t),
 		stateDir:                  t.TempDir(),
 		rulesDir:                  t.TempDir(),
 		"SWWAF_LOG_REMOTE_URL":    "syslog+tls://" + endpoint.Addr().String(),
@@ -930,7 +903,7 @@ func TestStalledRemoteLogEndpointHoldsUpNoRequest(t *testing.T) {
 	}
 
 	out := runUntilStopped(t, env, func(url string) {
-		wantGreeting(t, url)
+		wantAllowed(t, url)
 
 		// More than one line has been written, and the buffer holds the
 		// last.
@@ -980,7 +953,6 @@ func TestBanIsAlertedAndAnAlertNotSentIsKeptAcrossARestart(t *testing.T) {
 	dir := t.TempDir()
 	env := map[string]string{
 		listenAddr:                    localhost + ":0",
-		upstreamURL:                   startApp(t),
 		stateDir:                      dir,
 		rulesDir:                      rules,
 		"SWWAF_ALERT_WEBHOOK_URL":     webhook.url,
@@ -1065,10 +1037,8 @@ func TestBanIsAlertedToSlackAndNtfy(t *testing.T) {
 	slack, ntfy := startDestination(t), startDestination(t)
 	env := map[string]string{
 		listenAddr:      localhost + ":0",
-		upstreamURL:     startApp(t),
 		stateDir:        t.TempDir(),
 		rulesDir:        t.TempDir(),
-		trustedProxies:  localhost + "/32",
 		rateLimitPerDay: "1",
 		// The metrics are read from 127.0.0.1, which no limit counts.
 		"SWWAF_ALLOW_NETS":              localhost + "/32",
@@ -1208,8 +1178,8 @@ func startApp(t *testing.T) string {
 	return app.URL
 }
 
-// runUntilStopped runs smallwebwaf with the settings in env, has use send
-// it requests at url, then stops it as SIGTERM does, checks that it
+// runUntilStopped runs `smallwebwaf servewaf` with the settings in env, has use
+// send it requests at url, then stops it as SIGTERM does, checks that it
 // stopped in order, and returns its output.
 func runUntilStopped(
 	t *testing.T, env map[string]string, use func(url string),
@@ -1242,43 +1212,33 @@ func runUntilStopped(
 
 // wantStartingLine checks that the line at start gives the version and
 // every setting's value.
-func wantStartingLine(t *testing.T, line map[string]any, appURL, dir string) {
+func wantStartingLine(t *testing.T, line map[string]any, dir string) {
 	t.Helper()
 
 	settings, _ := line["settings"].(map[string]any)
 	want := map[string]any{
-		listenAddr:                              localhost + ":0",
-		upstreamURL:                             appURL,
-		stateDir:                                dir,
-		"SWWAF_MODE":                            "enforce",
-		stateWriteDelay:                         "10s",
-		stateCounterInterval:                    "15m",
-		trustedProxies:                          "10.0.0.0/8,172.16.0.0/12,192.168.0.0/16",
-		"SWWAF_CLIENT_REQUEST_TIMEOUT":          "60s",
-		"SWWAF_CLIENT_REQUEST_HEADER_MAX_BYTES": "32K",
-		"SWWAF_CLIENT_IDLE_TIMEOUT":             "120s",
-		"SWWAF_CLIENT_RESPONSE_TIMEOUT":         "30m",
-		"SWWAF_UPSTREAM_REQUEST_TIMEOUT":        "60s",
-		"SWWAF_UPSTREAM_RESPONSE_TIMEOUT":       "30m",
-		"SWWAF_REQUEST_MAX_BYTES":               "100M",
-		"SWWAF_RESPONSE_MAX_BYTES":              "1G",
-		"SWWAF_ALLOW_NETS":                      "",
-		rateLimitExemptNets:                     "",
-		"SWWAF_DENY_NETS":                       "",
-		"SWWAF_RATE_LIMIT_PER_MINUTE":           "500",
-		"SWWAF_RATE_LIMIT_PER_HOUR":             "20000",
-		rateLimitPerDay:                         "300000",
-		"SWWAF_RATE_LIMIT_EXEMPT_PATHS":         "",
-		"SWWAF_DENIED_COUNTRIES":                "",
-		"SWWAF_EXCLUSIVELY_ALLOWED_COUNTRIES":   "",
-		"SWWAF_BAN_RESPONSE":                    "403",
-		"SWWAF_LIMIT_BAN_DURATION":              "1h",
-		"SWWAF_LIMIT_BAN_REPEAT_WINDOW":         "24h",
-		"SWWAF_MAX_BAN_DURATION":                "7d",
-		"SWWAF_ATTACK_BAN_DURATION":             "7d",
-		"SWWAF_MAX_BANS":                        "5000",
-		"SWWAF_BAN_SCOPE_V4_PREFIX":             "32",
-		"SWWAF_RULES_ENABLED":                   "true",
+		listenAddr:                            localhost + ":0",
+		stateDir:                              dir,
+		"SWWAF_MODE":                          "enforce",
+		stateWriteDelay:                       "10s",
+		stateCounterInterval:                  "15m",
+		"SWWAF_ALLOW_NETS":                    "",
+		rateLimitExemptNets:                   "",
+		"SWWAF_DENY_NETS":                     "",
+		"SWWAF_RATE_LIMIT_PER_MINUTE":         "120",
+		"SWWAF_RATE_LIMIT_PER_HOUR":           "1500",
+		rateLimitPerDay:                       "6000",
+		"SWWAF_RATE_LIMIT_EXEMPT_PATHS":       "",
+		"SWWAF_DENIED_COUNTRIES":              "",
+		"SWWAF_EXCLUSIVELY_ALLOWED_COUNTRIES": "",
+		"SWWAF_BAN_RESPONSE":                  "403",
+		"SWWAF_LIMIT_BAN_DURATION":            "1h",
+		"SWWAF_LIMIT_BAN_REPEAT_WINDOW":       "24h",
+		"SWWAF_MAX_BAN_DURATION":              "7d",
+		"SWWAF_ATTACK_BAN_DURATION":           "7d",
+		"SWWAF_MAX_BANS":                      "5000",
+		"SWWAF_BAN_SCOPE_V4_PREFIX":           "32",
+		"SWWAF_RULES_ENABLED":                 "true",
 	}
 
 	for name, value := range want {
@@ -1292,30 +1252,11 @@ func wantStartingLine(t *testing.T, line map[string]any, appURL, dir string) {
 	}
 }
 
-// wantGreeting checks that a request to url gets the app's answer.
-func wantGreeting(t *testing.T, url string) {
+// wantAllowed checks that servewaf at url allows a request from localhost.
+func wantAllowed(t *testing.T, url string) {
 	t.Helper()
 
-	req, err := http.NewRequestWithContext(t.Context(), http.MethodGet, url,
-		http.NoBody)
-	if err != nil {
-		t.Fatalf("new request: %v", err)
-	}
-
-	transport := &http.Transport{}
-	defer transport.CloseIdleConnections()
-
-	res, err := (&http.Client{Transport: transport}).Do(req)
-	if err != nil {
-		t.Fatalf("request: %v", err)
-	}
-
-	body, err := io.ReadAll(res.Body)
-	_ = res.Body.Close()
-
-	if err != nil || string(body) != greeting {
-		t.Errorf("got %q (%v), want the app's answer", body, err)
-	}
+	wantStatus(t, url, localhost, http.StatusOK)
 }
 
 // messages returns the message of each record in received, octet-counted
@@ -1496,34 +1437,16 @@ func onlyBan(t *testing.T, dir string) map[string]any {
 	return file.Bans[0]
 }
 
-// wantRefused checks that a request to url is refused with 403, the
-// default SWWAF_BAN_RESPONSE.
+// wantRefused checks that servewaf at url refuses a request from localhost with
+// 403, the default SWWAF_BAN_RESPONSE.
 func wantRefused(t *testing.T, url string) {
 	t.Helper()
 
-	req, err := http.NewRequestWithContext(t.Context(), http.MethodGet, url,
-		http.NoBody)
-	if err != nil {
-		t.Fatalf("new request: %v", err)
-	}
-
-	transport := &http.Transport{}
-	defer transport.CloseIdleConnections()
-
-	res, err := (&http.Client{Transport: transport}).Do(req)
-	if err != nil {
-		t.Fatalf("request: %v", err)
-	}
-
-	_ = res.Body.Close()
-
-	if res.StatusCode != http.StatusForbidden {
-		t.Errorf("status %d, want %d", res.StatusCode, http.StatusForbidden)
-	}
+	wantStatus(t, url, localhost, http.StatusForbidden)
 }
 
-// wantStatus checks that a request to url from the client at from, as
-// X-Forwarded-For names it, is answered with status.
+// wantStatus checks that a request to url from the client at from, as statusFrom
+// sends it, is answered with status.
 func wantStatus(t *testing.T, url, from string, status int) {
 	t.Helper()
 
@@ -1690,8 +1613,10 @@ func (w *webhook) waitFor(t *testing.T, event string, answered bool) webhookPost
 	}
 }
 
-// statusFrom returns the status a request to url from the client at
-// from, as X-Forwarded-For names it, is answered with.
+// statusFrom returns the status a request to url from the client at from is
+// answered with. The request serves rproxy and servewaf alike. rproxy reads the
+// client from X-Forwarded-For, and replaces the other two headers. To servewaf,
+// they make it a question about that client.
 func statusFrom(t *testing.T, url, from string) int {
 	t.Helper()
 
@@ -1702,6 +1627,8 @@ func statusFrom(t *testing.T, url, from string) int {
 	}
 
 	req.Header.Set("X-Forwarded-For", from)
+	req.Header.Set(servewaf.ClientHeader, from)
+	req.Header.Set("X-Request-ID", rand.Text())
 
 	transport := &http.Transport{}
 	defer transport.CloseIdleConnections()

internal/state/state_test.go

@@ -648,6 +648,27 @@ func TestClientWithRefusalsInTheMinuteWithoutTheirStartStopsTheStart(t *testing.
 		`: entry 1 has no "minute_refusals.start"`)
 }
 
+func TestClientsJSONFromAnEarlierVersionWithTokenRefusalsLoads(t *testing.T) {
+	t.Parallel()
+
+	dir := t.TempDir()
+
+	err := os.WriteFile(filepath.Join(dir, clientsJSON),
+		[]byte(`{"version": 1, "clients": [{"client": "203.0.113.9/32", `+
+			`"history": {"offences": {"token_refused": 2}}}]}`), 0o600)
+	if err != nil {
+		t.Fatalf("write %s: %v", clientsJSON, err)
+	}
+
+	params := newParams(dir)
+	load(t, params)
+
+	clients := params.Limiter.Snapshot()
+	if len(clients) != 1 || clients[0].History.Offences.TokenRefused != 2 {
+		t.Errorf("clients %+v, want one with its two refusals kept", clients)
+	}
+}
+
 func TestReputationJSONEntryWithoutAFieldItNeedsStopsTheStart(t *testing.T) {
 	t.Parallel()
 

internal/waf/waf.go

@@ -212,8 +212,7 @@ type Result struct {
 // method, its URL with the query, and its headers, the Cookie header
 // without the cookies in cookiesNotRead, and on body, r's body as the
 // caller has it, as readBody reads it. It returns what it found, what it
-// read of body, which the app is still to be sent, and the error that
-// ended the reading early, if one did.
+// read of body, and the error that ended the reading early, if one did.
 func (c *CoreRuleSet) Inspect(
 	r *http.Request, client netip.Addr, body io.Reader,
 ) (Result, []byte, error) {

script/example-app

@@ -1,19 +1,28 @@
 #!/bin/sh
 # script/example-app: build the image, and on it the example app in
-# deploy/example-app, then run the app's container with a volume for the
-# state files and check that the health check passes, that a request is
-# served through smallwebwaf, that a second one in a minute bans the
-# client, that a probe for /.env bans another client, which its next
-# request bans for good, that `sv stop` stops smallwebwaf in order, that
-# `docker stop` stops the container without having to kill it, that a
-# new container on the same volume still refuses the banned client, that
-# a container with its state files on a new volume mounted at the
-# directory SWWAF_STATE_DIR_FILE names becomes healthy, and that one whose
-# SWWAF_STATE_DIR does not exist logs smallwebwaf's message about it. The
-# containers run with SWWAF_LOOKUP_SOURCE=off, so that no address is sent
-# to GeoJS. The containers, the volumes and both images are removed
-# however the script ends. Building the app needs network access, for
-# nixpkgs' binary cache. script/check does not run this.
+# deploy/example-app, then run the app's container, with rproxy in it, and
+# servewaf in a container of its own with a volume for the state files. It
+# checks:
+#   - that the health checks pass;
+#   - that a request is served through rproxy, and a second one in a minute
+#     bans the client;
+#   - that a probe for /.env bans another client, which its next request bans
+#     for good;
+#   - that only servewaf's container changes the state directory's owner;
+#   - that the app still answers through rproxy with servewaf stopped, and
+#     that once servewaf has started again, bans apply again;
+#   - that `sv stop` stops rproxy in order, and `docker stop` stops each
+#     container without having to kill it;
+#   - that a new servewaf container on the same volume still refuses the banned
+#     client;
+#   - that a servewaf container with its state files on a new volume mounted at
+#     the directory SWWAF_STATE_DIR_FILE names becomes healthy;
+#   - that one whose SWWAF_STATE_DIR does not exist logs servewaf's message
+#     about it.
+# servewaf runs with SWWAF_LOOKUP_SOURCE=off, so that no address is sent to
+# GeoJS. The containers, the network, the volumes and both images are removed
+# however the script ends. Building the app needs network access, for nixpkgs'
+# binary cache. script/check does not run this.
 set -eu
 
 SCRIPT_DIR="$(cd "$(dirname "$0")" && pwd -P)"
@@ -24,7 +33,9 @@ ROOT="$(cd "$SCRIPT_DIR/.." && pwd -P)"
 NAME="$("$SCRIPT_DIR/projectname")-example-$$"
 IMAGE="$NAME-base"
 APP_IMAGE="$NAME-app"
-CONTAINER="$NAME"
+NETWORK="$NAME"
+APP="$NAME-app-container"
+SERVEWAF="$NAME-servewaf"
 VOLUME="$NAME-state"
 # The volumes of the container whose state directory SWWAF_STATE_DIR_FILE
 # names: its state files, and the file that names their directory.
@@ -32,15 +43,18 @@ MOVED_VOLUME="$NAME-moved-state"
 SETTINGS_VOLUME="$NAME-settings"
 
 cleanup() {
-    docker rm --force "$CONTAINER" >/dev/null 2>&1 || true
+    docker rm --force "$APP" "$SERVEWAF" >/dev/null 2>&1 || true
+    docker network rm "$NETWORK" >/dev/null 2>&1 || true
     docker volume rm --force "$VOLUME" "$MOVED_VOLUME" "$SETTINGS_VOLUME" \
         >/dev/null 2>&1 || true
     docker rmi --force "$APP_IMAGE" "$IMAGE" >/dev/null 2>&1 || true
 }
 
 fail() {
-    echo "example-app: $*; the container's output:" >&2
-    docker logs "$CONTAINER" >&2 || true
+    echo "example-app: $*; the app container's output:" >&2
+    docker logs "$APP" >&2 || true
+    echo "example-app: servewaf's output:" >&2
+    docker logs "$SERVEWAF" >&2 || true
     exit 1
 }
 
@@ -57,52 +71,73 @@ wait_for() {
     done
 }
 
+# healthy <container>: docker says the container's health check passes.
 healthy() {
-    status="$(docker inspect --format '{{.State.Health.Status}}' "$CONTAINER")"
+    status="$(docker inspect --format '{{.State.Health.Status}}' "$1")"
     [ "$status" = healthy ]
 }
 
-# logged <text>...: a line of the container's output holds every text,
-# in any order.
+# logged <container> <text>...: a line of the container's output holds every
+# text, in any order.
 logged() {
-    lines="$(docker logs "$CONTAINER" 2>&1)"
+    lines="$(docker logs "$1" 2>&1)"
+    shift
     for text in "$@"; do
         lines="$(printf '%s\n' "$lines" | grep -F "$text")" || return 1
     done
 }
 
-# start_container: run the app's container, with the state files on the
-# volume, a rate limit of one request a minute and no client looked up,
-# and wait until it is healthy.
-start_container() {
-    docker run --detach --name "$CONTAINER" --publish 127.0.0.1::8080 \
+# start_servewaf: run servewaf from the image, with the state files on the
+# volume, a rate limit of one request a minute and no client looked up, and wait
+# until it is healthy.
+start_servewaf() {
+    docker run --detach --name "$SERVEWAF" --network "$NETWORK" \
         --volume "$VOLUME:/var/lib/smallwebwaf" \
+        --env SMALLWEBWAF_COMMAND=servewaf \
         --env SWWAF_RATE_LIMIT_PER_MINUTE=1 \
         --env SWWAF_LOOKUP_SOURCE=off \
-        "$APP_IMAGE" >/dev/null
-    wait_for "the health check did not pass" healthy
-    address="$(docker port "$CONTAINER" 8080/tcp)"
+        "$IMAGE" >/dev/null
+    wait_for "servewaf's health check did not pass" healthy "$SERVEWAF"
 }
 
-# start_moved_container: run the app's container with the state files on
-# a new volume at /srv/state, which SWWAF_STATE_DIR_FILE names in a file
-# only the smallwebwaf user can read, as under "Settings given as files"
-# in docs/settings.md, and wait until it is healthy. smallwebwaf can write the
-# new volume only once the run script has given it to that user.
-start_moved_container() {
+# start_app: run the app's container, with rproxy in it, and wait until it is
+# healthy.
+start_app() {
+    docker run --detach --name "$APP" --network "$NETWORK" --publish 127.0.0.1::8080 \
+        --env SWRP_WAF_BACKEND="http://$SERVEWAF:8080" \
+        "$APP_IMAGE" >/dev/null
+    wait_for "the app's health check did not pass" healthy "$APP"
+    address="$(docker port "$APP" 8080/tcp)"
+}
+
+# start_moved_servewaf: run servewaf with the state files on a new volume at
+# /srv/state, which SWWAF_STATE_DIR_FILE names in a file only the smallwebwaf
+# user can read, as under "Settings given as files" in docs/settings.md, and
+# wait until it is healthy. servewaf can write the new volume only once the run
+# script has given it to that user.
+start_moved_servewaf() {
     docker volume create "$MOVED_VOLUME" >/dev/null
     docker volume create "$SETTINGS_VOLUME" >/dev/null
     docker run --rm --volume "$SETTINGS_VOLUME:/settings" \
         --entrypoint bash "$IMAGE" -c 'echo /srv/state > /settings/state-dir &&
             chown smallwebwaf:smallwebwaf /settings/state-dir &&
             chmod 0400 /settings/state-dir'
-    docker run --detach --name "$CONTAINER" \
+    docker run --detach --name "$SERVEWAF" --network "$NETWORK" \
         --volume "$MOVED_VOLUME:/srv/state" \
         --volume "$SETTINGS_VOLUME:/etc/smallwebwaf/settings:ro" \
+        --env SMALLWEBWAF_COMMAND=servewaf \
         --env SWWAF_STATE_DIR_FILE=/etc/smallwebwaf/settings/state-dir \
         --env SWWAF_LOOKUP_SOURCE=off \
-        "$APP_IMAGE" >/dev/null
-    wait_for "the health check did not pass" healthy
+        "$IMAGE" >/dev/null
+    wait_for "servewaf's health check did not pass" healthy "$SERVEWAF"
+}
+
+# status_from <client> <path>: print the status a request for path from client,
+# as X-Forwarded-For names it, gets. rproxy believes the header from docker's
+# gateway, a private address.
+status_from() {
+    curl --silent --output /dev/null --write-out '%{http_code}' \
+        --max-time 10 --header "X-Forwarded-For: $1" "http://$address$2" || true
 }
 
 # refused: a request to the container gets 403, SWWAF_BAN_RESPONSE's
@@ -113,13 +148,14 @@ refused() {
     [ "$code" = 403 ]
 }
 
-# refused_from <client> <path>: a request for path from client, as
-# X-Forwarded-For names it, gets 403. smallwebwaf believes the header
-# from docker's gateway, a private address.
+# refused_from <client> <path>: a request for path from client gets 403.
 refused_from() {
-    code="$(curl --silent --output /dev/null --write-out '%{http_code}' \
-        --max-time 10 --header "X-Forwarded-For: $1" "http://$address$2")" || true
-    [ "$code" = 403 ]
+    [ "$(status_from "$1" "$2")" = 403 ]
+}
+
+# owner_of_state_dir <container>: print who owns /var/lib/smallwebwaf there.
+owner_of_state_dir() {
+    docker exec "$1" stat --format '%U' /var/lib/smallwebwaf
 }
 
 main() {
@@ -131,58 +167,88 @@ main() {
     docker build --no-cache --build-arg SMALLWEBWAF_IMAGE="$IMAGE" \
         -t "$APP_IMAGE" deploy/example-app
 
+    docker network create "$NETWORK" >/dev/null
     docker volume create "$VOLUME" >/dev/null
-    start_container
-    echo "example-app: the health check passes"
+    start_servewaf
+    start_app
+    echo "example-app: the health checks pass"
+
+    [ "$(owner_of_state_dir "$SERVEWAF")" = smallwebwaf ] ||
+        fail "servewaf's container did not give the state directory to smallwebwaf"
+    [ "$(owner_of_state_dir "$APP")" = root ] ||
+        fail "the app's container changed the state directory's owner"
+    echo "example-app: only servewaf's container changes the state directory's owner"
 
     page="$(curl --fail --silent --show-error --max-time 10 "http://$address/")" ||
         fail "no answer on port 8080"
     [ "$page" = "hello from the example app" ] || fail "port 8080 answered $page"
-    wait_for "smallwebwaf logged no request it forwarded" logged '"action":"forward"'
-    echo "example-app: smallwebwaf passes a request to the app and its answer back"
+    wait_for "servewaf logged no request it allowed" \
+        logged "$SERVEWAF" '"action":"forward"' '"servewaf_line":"report"'
+    echo "example-app: rproxy passes a request to the app and its answer back"
 
     refused || fail "a second request in a minute was not refused"
-    wait_for "smallwebwaf logged no ban" logged '"action":"rate_limited"'
+    wait_for "servewaf logged no ban" logged "$SERVEWAF" '"action":"rate_limited"'
     echo "example-app: a second request in a minute bans the client"
 
     refused_from 203.0.113.9 /.env || fail "a probe for /.env was not refused"
-    wait_for "smallwebwaf logged no ban for the probe" \
-        logged '"action":"banned"' '"rule_ids":["env-file"]'
+    wait_for "servewaf logged no ban for the probe" \
+        logged "$SERVEWAF" '"action":"banned"' '"rule_ids":["env-file"]'
     refused_from 203.0.113.9 / || fail "the client of the probe was let through"
     wait_for "the client's next request did not make its ban permanent" \
-        logged '"ban_expires":"permanent"'
+        logged "$SERVEWAF" '"ban_expires":"permanent"'
     echo "example-app: a probe for /.env bans the client, its next request for good"
 
-    docker exec "$CONTAINER" sv stop smallwebwaf >/dev/null ||
-        fail "sv stop smallwebwaf failed"
-    wait_for "smallwebwaf did not stop in order" logged '"msg":"stopped"'
-    echo "example-app: sv stop stops smallwebwaf in order"
+    docker exec "$SERVEWAF" sv stop smallwebwaf >/dev/null ||
+        fail "sv stop smallwebwaf failed in servewaf's container"
+    wait_for "servewaf did not stop in order" logged "$SERVEWAF" '"msg":"stopped"'
+    [ "$(status_from 203.0.113.9 /)" = 200 ] ||
+        fail "with servewaf stopped, the app did not answer through rproxy"
+    wait_for "rproxy logged no request SWRP_DEFAULT_DISPOSITION decided" \
+        logged "$APP" '"default_disposition":true'
+    docker exec "$APP" /usr/local/bin/smallwebwaf healthcheck ||
+        fail "with servewaf stopped, the app's health check failed"
+    echo "example-app: with servewaf stopped, the app answers through rproxy"
 
-    docker stop "$CONTAINER" >/dev/null
-    status="$(docker inspect --format '{{.State.ExitCode}}' "$CONTAINER")"
-    [ "$status" = 0 ] || fail "docker stop left exit status $status"
-    echo "example-app: docker stop stops the container in order"
+    docker exec "$SERVEWAF" sv start smallwebwaf >/dev/null ||
+        fail "sv start smallwebwaf failed in servewaf's container"
+    wait_for "once servewaf had started again, the ban did not apply" \
+        refused_from 203.0.113.9 /
+    echo "example-app: once servewaf has started again, bans apply again"
 
-    docker rm "$CONTAINER" >/dev/null
-    start_container
-    refused || fail "the new container let the banned client through"
-    wait_for "smallwebwaf logged no request refused under the ban" \
-        logged '"action":"banned"'
-    echo "example-app: a new container on the same volume keeps the ban"
+    docker exec "$APP" sv stop smallwebwaf >/dev/null ||
+        fail "sv stop smallwebwaf failed in the app's container"
+    wait_for "rproxy did not stop in order" logged "$APP" '"msg":"stopped"'
+    echo "example-app: sv stop stops rproxy in order"
 
-    docker rm --force "$CONTAINER" >/dev/null
-    start_moved_container
+    for container in "$APP" "$SERVEWAF"; do
+        docker stop "$container" >/dev/null
+        status="$(docker inspect --format '{{.State.ExitCode}}' "$container")"
+        [ "$status" = 0 ] || fail "docker stop left exit status $status"
+    done
+    echo "example-app: docker stop stops each container in order"
+
+    docker rm "$APP" "$SERVEWAF" >/dev/null
+    start_servewaf
+    start_app
+    refused || fail "the new servewaf container let the banned client through"
+    wait_for "servewaf logged no request refused under the ban" \
+        logged "$SERVEWAF" '"action":"banned"'
+    echo "example-app: a new servewaf container on the same volume keeps the ban"
+
+    docker rm --force "$SERVEWAF" >/dev/null
+    start_moved_servewaf
     echo "example-app: the run script gives the state files' directory named" \
         "by SWWAF_STATE_DIR_FILE to the smallwebwaf user"
 
-    docker rm --force "$CONTAINER" >/dev/null
-    docker run --detach --name "$CONTAINER" \
+    docker rm --force "$SERVEWAF" >/dev/null
+    docker run --detach --name "$SERVEWAF" --network "$NETWORK" \
+        --env SMALLWEBWAF_COMMAND=servewaf \
         --env SWWAF_STATE_DIR=/srv/missing \
         --env SWWAF_LOOKUP_SOURCE=off \
-        "$APP_IMAGE" >/dev/null
-    wait_for "smallwebwaf did not report the missing state directory" \
-        logged "SWWAF_STATE_DIR cannot be written"
-    echo "example-app: smallwebwaf reports a state directory that does not exist"
+        "$IMAGE" >/dev/null
+    wait_for "servewaf did not report the missing state directory" \
+        logged "$SERVEWAF" "SWWAF_STATE_DIR cannot be written"
+    echo "example-app: servewaf reports a state directory that does not exist"
 }
 
 main "$@"

script/gitea-requests

@@ -1,13 +1,14 @@
 #!/bin/sh
-# script/gitea-requests: build the image and run gitea 1.27.3 behind it,
-# with every setting of smallwebwaf at its default but SWWAF_UPSTREAM_URL,
-# which names gitea's container. Then send through it the gitea requests
-# that reading gitea's source found the Core Rule Set refuses, which
-# docs/gitea.md records, and a short sample of gitea's ordinary use:
-# signing in, pages of files and commits, a diff, the API, a push, clone
-# and fetch over HTTP, and two container image pushes. Last, print each
-# request smallwebwaf logged, with what it did with it and the ids of the
-# Core Rule Set's rules that matched it.
+# script/gitea-requests: build the image and run gitea 1.27.3 behind rproxy
+# and servewaf, three containers on one network. Every setting is at its
+# default but these: SWRP_UPSTREAM_URL names gitea's container, SWRP_WAF_BACKEND
+# names servewaf's, and SWWAF_LOG_REQUEST_HEADERS adds the header that labels a
+# request. Then send through rproxy the gitea requests that reading gitea's
+# source found the Core Rule Set refuses, which docs/gitea.md records, and a
+# short sample of gitea's ordinary use: signing in, pages of files and commits,
+# a diff, the API, a push, clone and fetch over HTTP, and two container image
+# pushes. Last, print each request servewaf logged, with what it did with it and
+# the ids of the Core Rule Set's rules that matched it.
 # Every request comes from one client, docker's gateway, so more than
 # SWWAF_ERROR_BURST_THRESHOLD, 30, refusals in a minute would ban it, and
 # the requests after would show as banned. The containers, the network,
@@ -29,7 +30,8 @@ GITEA_IMAGE="gitea/gitea@sha256:87a67ee09d3ae0d1df5fda5dcda3e2a1f9236a45b0a59025
 NAME="$("$SCRIPT_DIR/projectname")-gitea-$$"
 IMAGE="$NAME-image"
 NETWORK="$NAME"
-SMALLWEBWAF="$NAME-smallwebwaf"
+RPROXY="$NAME-rproxy"
+SERVEWAF="$NAME-servewaf"
 GITEA="$NAME-gitea"
 
 # gitea's one user, who owns the repository and the container images.
@@ -37,16 +39,23 @@ PASSWORD="owner-password"
 
 BROWSER="Mozilla/5.0 (X11; Linux x86_64; rv:131.0) Gecko/20100101 Firefox/131.0"
 
-# The files the script makes, and smallwebwaf's address once it runs,
-# localhost and the port docker publishes it on: a host name, since the
-# Core Rule Set takes a Host that is an IP address for a warning (920350).
+# The header that labels a request in the report. rproxy makes every request's
+# id itself, so a label cannot be the X-Request-ID.
+LABEL_HEADER="X-Case"
+
+# The default of SWWAF_LOG_REQUEST_HEADERS, and the header above.
+LOGGED_HEADERS="accept,accept-language,accept-encoding,content-type,origin,range,x-case"
+
+# The files the script makes, and rproxy's address once it runs, localhost and
+# the port docker publishes it on: a host name, since the Core Rule Set takes a
+# Host that is an IP address for a warning (920350).
 WORK=""
 address=""
 
 cleanup() {
     # So that a signal cannot stop it partway through.
     trap '' HUP INT TERM
-    docker rm --force --volumes "$SMALLWEBWAF" "$GITEA" >/dev/null 2>&1 || true
+    docker rm --force --volumes "$RPROXY" "$SERVEWAF" "$GITEA" >/dev/null 2>&1 || true
     docker network rm "$NETWORK" >/dev/null 2>&1 || true
     docker rmi --force "$IMAGE" >/dev/null 2>&1 || true
     if [ -n "$address" ]; then
@@ -75,30 +84,30 @@ wait_for() {
     done
 }
 
+# healthy <container>: docker says the container's health check passes.
 healthy() {
-    status="$(docker inspect --format '{{.State.Health.Status}}' "$SMALLWEBWAF")"
+    status="$(docker inspect --format '{{.State.Health.Status}}' "$1")"
     [ "$status" = healthy ]
 }
 
-# logged <text>...: a line of smallwebwaf's output holds every text, in
-# any order.
+# logged <text>...: a line of servewaf's output holds every text, in any order.
 logged() {
-    lines="$(docker logs "$SMALLWEBWAF" 2>&1)"
+    lines="$(docker logs "$SERVEWAF" 2>&1)"
     for text in "$@"; do
         lines="$(printf '%s\n' "$lines" | grep -F "$text")" || return 1
     done
 }
 
-# send <label> <path> <curl option>...: send a request for path to
-# smallwebwaf, with label as its X-Request-ID, which the report gives,
-# and keep the body of the answer in $WORK/answer. The Core Rule Set
-# reads that header too, so a label names no file the cases name.
+# send <label> <path> <curl option>...: send a request for path to rproxy, with
+# label in LABEL_HEADER, which the report gives, and keep the body of the answer
+# in $WORK/answer. The Core Rule Set reads that header too, so a label names no
+# file the cases name.
 send() {
     label="$1"
     path="$2"
     shift 2
     curl --silent --show-error --max-time 30 --output "$WORK/answer" \
-        --header "X-Request-ID: $label" "$@" "http://$address$path"
+        --header "$LABEL_HEADER: $label" "$@" "http://$address$path"
 }
 
 # page <label> <path> <curl option>...: send the request as a browser
@@ -173,7 +182,7 @@ make_repository() {
     echo "line 41" >>"$dir/src/java.base/share/classes/java/lang/Runtime.java"
     repo_git -C "$dir" commit --quiet --all --message "Add a line"
 
-    repo_git -C "$dir" -c "http.extraHeader=X-Request-ID: git-push" push --quiet \
+    repo_git -C "$dir" -c "http.extraHeader=$LABEL_HEADER: git-push" push --quiet \
         "http://owner:$PASSWORD@$address/owner/repo.git" main ||
         fail "the push of the repository failed"
 }
@@ -236,9 +245,8 @@ call_api() {
 # push_images: push a container image to owner/python3-app, then the same
 # image to owner/app. For the second, the case, docker asks gitea to take
 # its layer from owner/python3-app, naming it in the query parameter
-# from. docker sends no X-Request-ID, so its requests have the ids
-# smallwebwaf gives them. The image is one small file, imported rather
-# than built.
+# from. docker sends no label, so the report gives its requests none. The image
+# is one small file, imported rather than built.
 push_images() {
     echo "$NAME" >"$WORK/layer.txt"
     tar -cf - -C "$WORK" layer.txt |
@@ -258,10 +266,10 @@ push_images() {
 
 # clone_and_fetch: the clone and fetch over HTTP of the sample.
 clone_and_fetch() {
-    repo_git -c "http.extraHeader=X-Request-ID: git-clone" clone --quiet \
+    repo_git -c "http.extraHeader=$LABEL_HEADER: git-clone" clone --quiet \
         "http://owner:$PASSWORD@$address/owner/repo.git" "$WORK/clone" ||
         fail "the clone failed"
-    repo_git -C "$WORK/clone" -c "http.extraHeader=X-Request-ID: git-fetch" fetch --quiet ||
+    repo_git -C "$WORK/clone" -c "http.extraHeader=$LABEL_HEADER: git-fetch" fetch --quiet ||
         fail "the fetch failed"
 }
 
@@ -271,19 +279,19 @@ field() {
     printf '%s\n' "$2" | sed -n "s/.*\"$1\":\"\([^\"]*\)\".*/\1/p"
 }
 
-# report: print a line for each request smallwebwaf logged, but its
-# health checks: what it did with the request, the ids of the Core Rule
-# Set's rules that matched it, its X-Request-ID, and the request.
-# waf_blocked is a refusal by the Core Rule Set, and forward a request
-# passed on to gitea, whatever gitea answered.
+# report: print a line for each request rproxy reported to servewaf: what
+# servewaf did with the request, the ids of the Core Rule Set's rules that
+# matched it, its label, and the request. waf_blocked is a refusal by the Core
+# Rule Set, and forward a request passed on to gitea, whatever gitea answered.
 report() {
-    docker logs "$SMALLWEBWAF" 2>/dev/null | grep '"type":"request"' |
-        grep -v '"action":"admin"' | sed 's/\\u0026/\&/g' >"$WORK/requests"
+    docker logs "$SERVEWAF" 2>/dev/null | grep '"servewaf_line":"report"' |
+        sed 's/\\u0026/\&/g' >"$WORK/requests"
     while IFS= read -r line; do
         ids="$(printf '%s\n' "$line" | sed -n 's/.*"waf_rule_ids":\[\([0-9,]*\)\].*/\1/p')"
         query="$(field query "$line")"
+        label="$(field x-case "$line")"
         printf '%-11s %-13s %-17s %s %s%s\n' "$(field action "$line")" "${ids:--}" \
-            "$(field request_id "$line")" "$(field method "$line")" \
+            "${label:--}" "$(field method "$line")" \
             "$(field path "$line")" "${query:+?$query}"
     done <"$WORK/requests"
     echo "gitea-requests: $(grep -c . "$WORK/requests") requests," \
@@ -298,24 +306,30 @@ main() {
 
     docker build --no-cache -t "$IMAGE" .
 
-    # smallwebwaf first, so that gitea can be given the address it is
-    # reached at, and gitea's image pulled before, so that gitea starts
-    # within the minute smallwebwaf's health check waits for it.
+    # rproxy first, so that gitea can be given the address it is reached at,
+    # and gitea's image pulled before, so that gitea starts within the minute
+    # rproxy's health check waits for it.
     docker pull --quiet "$GITEA_IMAGE" >/dev/null
     docker network create "$NETWORK" >/dev/null
-    docker run --detach --name "$SMALLWEBWAF" --network "$NETWORK" \
-        --publish 127.0.0.1::8080 \
-        --env SWWAF_UPSTREAM_URL="http://$GITEA:3000" \
+    docker run --detach --name "$SERVEWAF" --network "$NETWORK" \
+        --env SMALLWEBWAF_COMMAND=servewaf \
+        --env SWWAF_LOG_REQUEST_HEADERS="$LOGGED_HEADERS" \
         "$IMAGE" >/dev/null
-    published="$(docker port "$SMALLWEBWAF" 8080/tcp)"
+    wait_for "servewaf's health check did not pass" healthy "$SERVEWAF"
+    docker run --detach --name "$RPROXY" --network "$NETWORK" \
+        --publish 127.0.0.1::8080 \
+        --env SWRP_UPSTREAM_URL="http://$GITEA:3000" \
+        --env SWRP_WAF_BACKEND="http://$SERVEWAF:8080" \
+        "$IMAGE" >/dev/null
+    published="$(docker port "$RPROXY" 8080/tcp)"
     address="localhost:${published##*:}"
 
     docker run --detach --name "$GITEA" --network "$NETWORK" \
         --env GITEA__security__INSTALL_LOCK=true \
         --env GITEA__server__ROOT_URL="http://$address/" \
         "$GITEA_IMAGE" >/dev/null
-    # smallwebwaf's health check passes once gitea takes connections.
-    wait_for "the health check did not pass" healthy
+    # rproxy's health check passes once gitea takes connections.
+    wait_for "rproxy's health check did not pass" healthy "$RPROXY"
     docker exec --user git "$GITEA" gitea admin user create --admin \
         --username owner --password "$PASSWORD" --email owner@example.invalid \
         --must-change-password=false >/dev/null
@@ -328,8 +342,8 @@ main() {
 
     # The fetch's last request is the last of all; once it is logged, so
     # is every other.
-    wait_for "smallwebwaf logged no line for the fetch" \
-        logged '"request_id":"git-fetch"' '"method":"POST"'
+    wait_for "servewaf logged no report of the fetch" \
+        logged '"x-case":"git-fetch"' '"method":"POST"' '"servewaf_line":"report"'
     report
 }
 

script/gitea-setup

@@ -0,0 +1,216 @@
+#!/bin/sh
+# script/gitea-setup: build the image, bring up deploy/gitea under a project
+# name of its own, and check it:
+#   - that a page load, a push and a clone sent through traefik pass through
+#     rproxy, and that servewaf checks them;
+#   - that gitea logs the visitor's address, not rproxy's;
+#   - that a request from a container on the shared network skips the checks;
+#   - that with servewaf stopped, gitea still answers through rproxy.
+# It publishes no port of traefik's, since this host's ports 80 and 443 may be
+# taken. It reaches traefik at its address on the shared network instead, so
+# its own requests come from the network's gateway, which servewaf checks like
+# any visitor. Two runs at once on one docker host cannot both start, since
+# both would use the subnet compose.yaml names. The containers, the network,
+# the volumes, the image and the files the script makes are removed however it
+# ends; the gitea and traefik images stay, as the base images of a build do.
+# It needs network access. script/check does not run this.
+set -eu
+
+SCRIPT_DIR="$(cd "$(dirname "$0")" && pwd -P)"
+ROOT="$(cd "$SCRIPT_DIR/.." && pwd -P)"
+
+# Named after this run, so that runs in other clones on the same host
+# never touch each other's.
+NAME="$("$SCRIPT_DIR/projectname")-gitea-setup-$$"
+IMAGE="$NAME-image"
+NETWORK="${NAME}_shared"
+VISITOR="$NAME-visitor"
+
+# The site's host name and gitea's image, as deploy/gitea/compose.yaml names
+# them. gitea's image also runs the container on the shared network.
+SITE="git.example.org"
+# gitea 1.27.3, 2026-08-29
+GITEA_IMAGE="gitea/gitea@sha256:87a67ee09d3ae0d1df5fda5dcda3e2a1f9236a45b0a59025d6e00e46adc43bef"
+
+# gitea's one user, who owns the repository.
+PASSWORD="owner-password"
+
+# The files the script makes, gitea's secret key for this run, and traefik's
+# and the gateway's addresses on the shared network once the setup runs.
+WORK=""
+secret_key=""
+traefik=""
+gateway=""
+
+cleanup() {
+    # So that a signal cannot stop it partway through.
+    trap '' HUP INT TERM
+    docker rm --force "$VISITOR" >/dev/null 2>&1 || true
+    if [ -n "$WORK" ]; then
+        compose down --volumes --remove-orphans --timeout 5 >/dev/null 2>&1 || true
+        rm -rf "$WORK"
+    fi
+    docker rmi --force "$IMAGE" >/dev/null 2>&1 || true
+}
+
+# compose <argument>...: docker compose on the setup, under this run's project
+# name, with the image built here, this run's secret key and no port of
+# traefik's published.
+compose() {
+    SMALLWEBWAF_IMAGE="$IMAGE" GITEA_SECRET_KEY="$secret_key" \
+        docker compose --project-name "$NAME" \
+        --file "$ROOT/deploy/gitea/compose.yaml" --file "$WORK/no-ports.yaml" "$@"
+}
+
+fail() {
+    echo "gitea-setup: $*; the last lines of each container's output:" >&2
+    compose logs --no-color --tail 30 >&2 || true
+    exit 1
+}
+
+# wait_for <what fails> <command>...: run the command every second until
+# it succeeds, for at most a minute.
+wait_for() {
+    failure="$1"
+    shift
+    tries=0
+    until "$@"; do
+        tries=$((tries + 1))
+        [ "$tries" -lt 60 ] || fail "$failure"
+        sleep 1
+    done
+}
+
+# logged <service> <text>...: a line of the service's output holds every text,
+# in any order.
+logged() {
+    lines="$(compose logs --no-color --no-log-prefix "$1" 2>&1)"
+    shift
+    for text in "$@"; do
+        lines="$(printf '%s\n' "$lines" | grep -F -e "$text")" || return 1
+    done
+}
+
+# send <path> <curl option>...: send a request for path to the site, at
+# traefik's address, and print the status of the answer, 000 for none. traefik
+# answers with a certificate it made itself, since the setup names no
+# certificate resolver.
+send() {
+    path="$1"
+    shift
+    curl --silent --show-error --insecure --max-time 30 --output /dev/null \
+        --write-out '%{http_code}' --resolve "$SITE:443:$traefik" "$@" \
+        "https://$SITE$path" || true
+}
+
+# routed: traefik passes a request for the site's front page on to gitea.
+routed() {
+    [ "$(send / 2>/dev/null)" = 200 ]
+}
+
+# site_git <git argument>...: run git as the owner, without the host's own git
+# settings, reaching the site at traefik's address. git gives up on a transfer
+# slower than 1000 bytes a second for 30 seconds.
+site_git() {
+    GIT_CONFIG_GLOBAL=/dev/null GIT_CONFIG_NOSYSTEM=1 git \
+        -c user.name=owner -c user.email=owner@example.invalid \
+        -c http.sslVerify=false -c "http.curloptResolve=$SITE:443:$traefik" \
+        -c http.lowSpeedLimit=1000 -c http.lowSpeedTime=30 "$@"
+}
+
+# address_of <service>: print the service's address on the shared network.
+address_of() {
+    docker inspect --format "{{(index .NetworkSettings.Networks \"$NETWORK\").IPAddress}}" \
+        "$(compose ps --quiet "$1")"
+}
+
+# passed_through <method> <path>: rproxy passed a request from the gateway for
+# path to gitea on servewaf's allow, and servewaf checked it: its report line
+# gives the client's counts and the Core Rule Set's score.
+passed_through() {
+    wait_for "rproxy logged no $1 $2 that servewaf allowed" logged rproxy \
+        "\"method\":\"$1\"" "\"path\":\"$2\"" "\"client_ip\":\"$gateway\"" \
+        '"disposition":"allow"'
+    wait_for "servewaf logged no check of $1 $2" logged servewaf \
+        '"servewaf_line":"report"' "\"method\":\"$1\"" "\"path\":\"$2\"" \
+        "\"client_ip\":\"$gateway\"" '"action":"forward"' '"counts":' '"waf_score":'
+}
+
+main() {
+    cd "$ROOT"
+    trap cleanup EXIT
+    trap 'exit 1' HUP INT TERM
+    WORK="$(mktemp -d)"
+    printf 'services:\n    traefik:\n        ports: !reset []\n' >"$WORK/no-ports.yaml"
+
+    docker build --no-cache -t "$IMAGE" .
+    secret_key="$(docker run --rm "$GITEA_IMAGE" gitea generate secret SECRET_KEY)"
+
+    # rproxy is healthy once gitea takes connections.
+    compose up --detach --quiet-pull --wait --wait-timeout 120 ||
+        fail "the setup did not start"
+    traefik="$(address_of traefik)"
+    gateway="$(docker network inspect --format '{{(index .IPAM.Config 0).Gateway}}' "$NETWORK")"
+    wait_for "traefik did not route the site to rproxy" routed
+
+    compose exec --user git gitea gitea admin user create --admin \
+        --username owner --password "$PASSWORD" --email owner@example.invalid \
+        --must-change-password=false >/dev/null || fail "creating gitea's user failed"
+    status="$(send /api/v1/user/repos --user "owner:$PASSWORD" \
+        --header "Content-Type: application/json" --data '{"name":"repo"}')"
+    [ "$status" = 201 ] || fail "creating the repository was answered $status"
+
+    status="$(send /owner/repo)"
+    [ "$status" = 200 ] || fail "the repository's page was answered $status"
+    passed_through GET /owner/repo
+    echo "gitea-setup: a page load passes through rproxy, and servewaf checks it"
+
+    wait_for "gitea did not log the visitor's address" logged gitea \
+        "GET /owner/repo for $gateway:"
+    echo "gitea-setup: gitea logs the visitor's address, not rproxy's"
+
+    site_git init --quiet --initial-branch=main "$WORK/repo"
+    echo "hello" >"$WORK/repo/README.md"
+    site_git -C "$WORK/repo" add README.md
+    site_git -C "$WORK/repo" commit --quiet --message "Add a README"
+    site_git -C "$WORK/repo" push --quiet \
+        "https://owner:$PASSWORD@$SITE/owner/repo.git" main ||
+        fail "the push failed"
+    passed_through POST /owner/repo.git/git-receive-pack
+    echo "gitea-setup: a push passes through rproxy, and servewaf checks it"
+
+    site_git clone --quiet "https://owner:$PASSWORD@$SITE/owner/repo.git" \
+        "$WORK/clone" || fail "the clone failed"
+    [ "$(cat "$WORK/clone/README.md")" = hello ] || fail "the clone lacks the README"
+    passed_through POST /owner/repo.git/git-upload-pack
+    echo "gitea-setup: a clone passes through rproxy, and servewaf checks it"
+
+    # A container on the shared network, as sandcastle is, asks for the site
+    # by its name, and so reaches traefik from its own address.
+    status="$(docker run --rm --name "$VISITOR" --network "$NETWORK" \
+        --entrypoint curl "$GITEA_IMAGE" --silent --insecure --max-time 30 \
+        --output /dev/null --write-out '%{http_code}' "https://$SITE/api/v1/version" ||
+        true)"
+    [ "$status" = 200 ] || fail "the request from the shared network was answered $status"
+    wait_for "servewaf logged no request from the shared network" logged servewaf \
+        '"servewaf_line":"report"' '"path":"/api/v1/version"' '"action":"forward"'
+    line="$(compose logs --no-color --no-log-prefix servewaf |
+        grep -F '"servewaf_line":"report"' | grep -F '"path":"/api/v1/version"')"
+    case "$line" in
+        *"\"client_ip\":\"$gateway\""*)
+            fail "the request from the shared network came from the gateway" ;;
+        *'"counts":'* | *'"waf_score":'*)
+            fail "servewaf checked the request from the shared network" ;;
+    esac
+    echo "gitea-setup: a request from the shared network skips the checks"
+
+    compose stop servewaf >/dev/null 2>&1 || fail "servewaf did not stop"
+    status="$(send /owner/repo)"
+    [ "$status" = 200 ] ||
+        fail "with servewaf stopped, the repository's page was answered $status"
+    wait_for "rproxy logged no request SWRP_DEFAULT_DISPOSITION decided" \
+        logged rproxy '"path":"/owner/repo"' '"default_disposition":true'
+    echo "gitea-setup: with servewaf stopped, gitea answers through rproxy"
+}
+
+main "$@"