README rewritten from scratch so a newcomer can follow it (closes #154, closes #155)

The old README opened with project history and one list of a hundred
settings. The new one leads with what smallwebwaf is, what it protects
against, how to build and deploy it, what happens to a request, the
settings most deployments touch, how to check it works, the entrypoints,
the rationale and the design, as REPO_POLICIES.md requires. The reference
lists, every setting, the rule file format, the endpoints, the request
log's fields, the alert events, the metrics, the state files, the image
and the gitea notes, move to files under docs/, each linked from the
README, with SPEC.md as the one place for behaviour. Every statement was
checked against the code on next.

Model: fable-5-1

README.md

@@ -8,7 +8,8 @@ scanners and other abusers before they reach the app.
 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.
+app's answers back. A request it does not refuse reaches the app as it came,
+apart from a few headers (see "Design" below).
 
 It needs no setting. Every setting has a default chosen for a service on the
 open internet. [`SPEC.md`](SPEC.md) says how `smallwebwaf` behaves and why. The
@@ -17,10 +18,10 @@ reference documents under [`docs/`](docs/) are listed under "Documents" below.
 ## What it protects against
 
 - Scrapers that fetch every page of a site, all day. Rate limiting gives each
-  client 6000 requests a minute, 100,000 an hour and 1,000,000 a day. Byte
-  limits give it 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
+  client 1000 requests a minute, 10,000 an hour and 50,000 a day. Byte limits
+  give it 10 GiB a minute, 20 GiB an hour and 50 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.
 - 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
@@ -29,8 +30,8 @@ reference documents under [`docs/`](docs/) are listed under "Documents" below.
   of your own, or an entry in `SWWAF_TRAP_PATHS`, bans those 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
+  common web attacks. Coraza, a Go engine, runs those rules (step 11 under "What
+  happens to a request" below). 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;
@@ -141,32 +142,89 @@ while working on it, see "Entrypoints" below.
 
 ## What happens to a request
 
-`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.
+Two terms recur below. A clear sign of attack is a request that matches a rule
+whose action is `ban`, or asks for a trap path (steps 9 and 10). An offence is a
+request that counts against its client in its history. It is one of:
 
-1. The health check, `GET /_smallwebwaf/healthz`, is answered at once.
-2. The client is identified.
-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.
-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.
+- a clear sign of attack;
+- a broken limit;
+- a refusal by a rule, by the Core Rule Set or for a missing or wrong token.
 
-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)).
+`smallwebwaf` handles each request in this order. A request one step refuses
+skips the steps after it, apart from step 13. Nothing of a refused request
+reaches the app. "What happens to a request" in [`SPEC.md`](SPEC.md) gives each
+step in full.
+
+1. `GET /_smallwebwaf/healthz` is answered `200` with `ok` at once, before any
+   check and without asking the app.
+2. The client is worked out. A netblock is a range of addresses, written as an
+   address and a prefix length: `203.0.113.0/24`. `SWWAF_TRUSTED_PROXIES` lists
+   the netblocks traefik comes from, by default the private address ranges. For
+   a TCP peer inside them, `X-Forwarded-For` is read from the right, and the
+   first address outside those netblocks is the client. A peer outside them is
+   the client itself. An IPv6 client is its group: the whole netblock around its
+   address, a /64 by default; `SWWAF_IPV6_GROUP_PREFIX` sets its length.
+3. A client in `SWWAF_ALLOW_NETS` skips steps 4 to 11, the byte limits and the
+   error burst, but still needs a token at step 12. A client in
+   `SWWAF_DENY_NETS` is refused.
+4. A client under a ban is refused. If the ban was made for a clear sign of
+   attack, this request makes it permanent.
+5. The client's AS number and country are looked up, unless
+   `SWWAF_LOOKUP_SOURCE` is `off`. An AS number names the network an address
+   belongs to, such as `AS64496`.
+6. The country lists are checked. A client from a country in
+   `SWWAF_DENIED_COUNTRIES` is refused. When
+   `SWWAF_EXCLUSIVELY_ALLOWED_COUNTRIES` is set, a client from any other country
+   is refused, and so is a client without a country. Such a refusal is not an
+   offence.
+7. The reputation sources are checked: the blocklists, the CrowdSec decision
+   list, the DNS blocklists and AbuseIPDB. A client on the CrowdSec decision
+   list is banned until the decision ends. Any other source refuses the client,
+   lowers its limits or only notes it, as `SWWAF_BLOCKLIST_ACTION` and
+   `SWWAF_REPUTATION_ACTION` say. No request waits for a query.
+8. Rate limiting counts the request, unless the client or the path is exempt. A
+   request that takes the client over a limit is refused and bans the client.
+9. A request for a path in `SWWAF_TRAP_PATHS` is refused and bans the client, as
+   a clear sign of attack.
+10. The rule files are checked. A `log` rule notes the match. A `block` rule
+    refuses the request. A `ban` rule refuses it and bans the client, as a clear
+    sign of attack.
+11. The Core Rule Set inspects the request's method, URL and headers, and, once
+    `SWWAF_WAF_BODY_LIMIT` is set, form, JSON and XML bodies. A request it takes
+    for an attack is refused while `SWWAF_WAF_MODE` is `block`, the default, and
+    let through while it is `detect`. It bans no one by itself.
+12. A request under `/_smallwebwaf/` is answered here by `smallwebwaf`, after
+    its token is checked. Any other request is passed to the app. The app's
+    answer is streamed back within the size and time limits.
+13. Once the answer has ended, a request passed to the app has its bytes counted
+    for the byte limits. If a rule, a trap path, the Core Rule Set or a token
+    check refused the request, the refusal is counted for the error burst. The
+    client's history and the anomaly counters are updated. More than
+    `SWWAF_ERROR_BURST_THRESHOLD` refusals of one client in a minute ban it.
+
+In `observe` mode (`SWWAF_MODE=observe`), `smallwebwaf` makes no ban of its own.
+It refuses a request only for a size or time limit, or for a missing or wrong
+token. A request it would otherwise have refused is passed to the app, and its
+log line says what `enforce` mode would have done. Observe mode is for trying a
+configuration before enforcing it.
+
+What a refused visitor sees:
+
+- `SWWAF_BAN_RESPONSE`, by default `403` with the plain text `Forbidden`. It can
+  be `429` instead, or `close`, which closes the connection, so that traefik
+  answers `502`. It answers:
+    - a ban or a broken rate limit;
+    - a `ban` rule or a trap path;
+    - `SWWAF_DENY_NETS` and the country lists;
+    - a reputation source whose action is `deny`.
+- `403` for a `block` rule and the Core Rule Set.
+- For a size or time limit:
+    - `431` for headers over their limit;
+    - `413` for a body over its limit;
+    - `408` for a client too slow to send its body;
+    - `502` or `504` when the app passes a limit or cannot be reached.
+- `401` from an endpoint of `smallwebwaf`'s own, for a request without its
+  token.
 
 ## Settings you are likely to touch
 
@@ -175,11 +233,8 @@ Each setting is an environment variable of the app's container, such as
 [`docs/settings.md`](docs/settings.md) lists every setting, its default and the
 values it takes. The ones most deployments touch:
 
-- `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_MODE=observe`: log what would have been refused, refuse almost nothing,
+  ban no one. For trying a configuration.
 - `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
@@ -321,32 +376,50 @@ nixpkgs fixed at one release. An app's `Dockerfile` installs a package with
 [`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 `smallwebwaf` 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
+- The container's first process is `runsvinit`, which starts runit, a service
+  supervisor. runit runs the `run` script of each directory under
+  `/etc/service`, and runs it again a second after its program exits.
+  `smallwebwaf` runs as the `smallwebwaf` user (uid 65532) and the app as a user
+  of its own. So the app cannot touch the state files or the process of
+  `smallwebwaf`.
+- `smallwebwaf` listens on port 8080, on every address. traefik sends the app's
+  requests there. `smallwebwaf` passes them 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`. The health check, the metrics and the ban management are on the
+  same port, under `/_smallwebwaf/`. A request for that prefix never reaches the
+  app.
+- The app sees what it would see from traefik directly: the same `Host`, the
+  same `X-Forwarded-Proto`, and `X-Forwarded-For` with traefik's address added
+  at the end. The app's TCP peer is `smallwebwaf` on `127.0.0.1`. So the app
+  must trust `127.0.0.1` and `::1` for forwarded headers, besides the private
+  address ranges. An app that keeps its usual trusted proxies sees every visitor
+  as `127.0.0.1`. Each request also carries its id in `X-Request-ID`. Any
+  `X-Client-ASN` or `X-Client-Country` header a client sent is removed.
+- Both processes start with the container's environment variables. That is why
+  every setting of `smallwebwaf` starts with `SWWAF_`. A token given as an
+  environment variable is readable by the app. A token given as a file that only
+  the `smallwebwaf` user can read is not (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.
-- `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
+- The state files live in `/var/lib/smallwebwaf`. Without a volume there, they
+  survive a restart of the container and are lost when a deploy replaces it. The
+  `run` script gives that directory and every file in it to the `smallwebwaf`
+  user at each start, so a host directory mounted there needs no change of
+  owner.
+- The image's health check passes while `smallwebwaf` answers
+  `GET /_smallwebwaf/healthz` and the app accepts connections. traefik sends a
+  container no requests until it is healthy.
+- When `smallwebwaf` or the app exits, runit starts it again a second later. The
+  other process keeps running. While either is down, the client gets `502`. A
+  `smallwebwaf` that stops at start, as on an invalid setting, is started again
+  every second until the cause is fixed, and logs its message each time.
+- `docker stop` has runit send `SIGTERM` to both processes at once.
+  `smallwebwaf` gives the requests in progress five seconds to finish and writes
+  its state files. To let them finish, 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.
+"Deployment" in [`SPEC.md`](SPEC.md) has the rest: moving `smallwebwaf` to
+another port, the health check's timing, and the forwarded headers.
+"Architecture" in [`SPEC.md`](SPEC.md) lists the packages and what each does.
 
 ## TODO
 

docs/alerts.md

@@ -42,7 +42,7 @@ on one line:
     "asn": "",
     "as_name": "",
     "country": "",
-    "reason": "requests per minute over the limit of 6000",
+    "reason": "requests per minute over the limit of 1000",
     "detail": {
         "ban_expires": "2026-10-06T13:00:00.123Z",
         "cause": "limit",
@@ -51,9 +51,9 @@ on one line:
             "as_name": "",
             "country": "",
             "kind": "requests",
-            "limit": 6000,
+            "limit": 1000,
             "window": "minute",
-            "count": 6001,
+            "count": 1001,
             "request": {
                 "time": "2026-10-06T12:00:00.123456789Z",
                 "method": "GET",
@@ -62,7 +62,7 @@ on one line:
                 "status": 403,
                 "user_agent": "scraper/1.0"
             },
-            "requests": 8210,
+            "requests": 5210,
             "refused": 0,
             "earlier_bans": {
                 "limit": 0,
@@ -79,17 +79,16 @@ on one line:
 - `instance`: `SWWAF_INSTANCE_NAME`. `time`: when the alert was raised. `event`:
   one of the events above.
 - `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
-  one of:
+  `source_failure` and `file_error`.
+- `netblock`: empty for `source_failure` and `file_error`; otherwise one of:
     - the ban's netblock;
-    - the netblock an anomaly counted, empty in the `asn` and `total` scopes;
+    - the netblock an anomaly counted;
     - for the other events, 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 known when the alert was
   raised. They are empty when GeoJS had not answered yet.
 - `reason`: a short sentence, such as
-  `requests per minute over the limit of 6000` or `listed by a blocklist`.
+  `requests per minute over the limit of 1000` or `listed by a blocklist`.
 - `detail`: what is particular to the event:
     - for a ban, its `cause`, `ban_expires` and `notes` (the notes are listed
       under `bans.json` in [`state-files.md`](state-files.md));
@@ -98,8 +97,6 @@ on one line:
     - for a Core Rule Set match, the `rule_ids`, `score`, `method` and `path`;
     - for a source failure, the `source` and `error`;
     - for a file error, the `file` and `error`;
-    - for a summary, the `hour` it covers, the `count` of alerts held back, and
-      that count by event in `events`;
     - `mode`, when the request was not refused: `detect` or `observe`.
 - `suppressed_repeats`: how many repeats the cooldown held back before this
   alert.

docs/gitea.md

@@ -11,10 +11,8 @@ checked again when gitea or the Core Rule Set changes version.
 
 - 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 clone is a response. It fits the defaults of 30 minutes and 5 GiB for all
+  but the largest repositories and slowest links.
 - A push is a request, and so is every other upload:
     - a git push;
     - an LFS object;
@@ -32,13 +30,12 @@ checked again when gitea or the Core Rule Set changes version.
   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
-  172,800 requests, under the request limits. Six such runners on one address,
-  each busy all day, pass the day limit of 1,000,000 within two days; five stay
-  under it. 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`.
+  43,200 requests a day, and reports a running job's log and state every second.
+  So it passes the day limit of 50,000 after about an hour and a quarter of
+  jobs. It is then banned, the job it is running fails, and each repeat within a
+  day makes the ban longer. Newer runners ask less often, but a busy one, or
+  several on one address, can still pass it. Put the runners' addresses in
+  `SWWAF_RATE_LIMIT_EXEMPT_NETS`.
 
 ## What the Core Rule Set lets through
 

docs/metrics.md

@@ -1,8 +1,8 @@
 # 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`.
+The metrics `GET /_smallwebwaf/metrics` answers with, as "Metrics endpoint" in
+[`SPEC.md`](../SPEC.md) describes it. Prometheus keeps the `instance` label as
+`exported_instance` unless the scrape sets `honor_labels: true`.
 
 ## Traffic
 

docs/settings.md

@@ -91,24 +91,24 @@ that take `off`, the `_FILE` form, and what each group does and why.
 ## Static lists
 
 - `SWWAF_ALLOW_NETS` (default empty): netblocks you trust, such as your
-  monitoring (see step 3 in [`SPEC.md`](../SPEC.md)).
+  monitoring. Their clients are refused only for a size or time limit or a
+  missing or wrong token.
 - `SWWAF_RATE_LIMIT_EXEMPT_NETS` (default empty): netblocks whose clients are
   exempt from rate limiting and the byte limits.
-- `SWWAF_DENY_NETS` (default empty): netblocks whose clients are refused (see
-  step 3 in [`SPEC.md`](../SPEC.md)).
+- `SWWAF_DENY_NETS` (default empty): netblocks whose clients are always refused.
 
 ## Request rate limits, per client
 
-- `SWWAF_RATE_LIMIT_PER_MINUTE` (default `6000`), `SWWAF_RATE_LIMIT_PER_HOUR`
-  (default `100000`) and `SWWAF_RATE_LIMIT_PER_DAY` (default `1000000`): the
-  most requests a client may make in each window. A count or `off`.
+- `SWWAF_RATE_LIMIT_PER_MINUTE` (default `1000`), `SWWAF_RATE_LIMIT_PER_HOUR`
+  (default `10000`) and `SWWAF_RATE_LIMIT_PER_DAY` (default `50000`): the most
+  requests a client may make in each window. A count or `off`.
 - `SWWAF_RATE_LIMIT_EXEMPT_PATHS` (default empty): path prefixes exempt from
   rate limiting and the byte limits, such as `/assets/`.
 
 ## 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 `10G`), `SWWAF_BYTES_LIMIT_PER_HOUR`
+  (default `20G`) and `SWWAF_BYTES_LIMIT_PER_DAY` (default `50G`): 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`.
@@ -131,18 +131,12 @@ that take `off`, the `_FILE` form, and what each group does and why.
   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
+- `SWWAF_RESPONSE_MAX_BYTES` (default `5G`): 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
-  the start while a setting that needs a lookup is set:
-    - the two country lists;
-    - `SWWAF_ADD_LOOKUP_HEADERS`;
-    - the four biased threshold lists and `SWWAF_ASN_LIMIT_PERCENT_URL`;
-    - `SWWAF_UNKNOWN_LIMIT_PERCENT` below `100`;
-    - an anomaly threshold per AS number.
+- `SWWAF_LOOKUP_SOURCE` (default `geojs`): `geojs`, `file` or `off`.
 - `SWWAF_LOOKUP_DB_PATH` (default empty): the IPinfo Lite database file, in its
   `.mmdb` form, for `SWWAF_LOOKUP_SOURCE=file`.
 - `SWWAF_LOOKUP_TIMEOUT` (default `1s`): how long a request waits for its
@@ -196,7 +190,8 @@ that take `off`, the `_FILE` form, and what each group does and why.
 - `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`.
 - `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`.
+  in a minute for a rule match, a trap path, a Core Rule Set match or a failed
+  token check. A count or `off`.
 
 ## Ban lengths, response and scope
 
@@ -291,7 +286,7 @@ as `REQUESTS_PER_MINUTE`:
       client;
     - `SWWAF_ANOMALY_NET_V6_PREFIX` (default `48`, from 0 to 128) for an IPv6
       client.
-- `SWWAF_ANOMALY_ASN_...`: per AS number.
+- `SWWAF_ANOMALY_ASN_...`: per AS number. Needs a lookup source.
 - `SWWAF_ANOMALY_TOTAL_...`: the whole service.
 - `SWWAF_WATCH_...`: each netblock in `SWWAF_WATCH_NETS`, as a whole.
   `SWWAF_WATCH_NETS` (default empty) is a list of name, `=` and netblock, such

internal/alerts/alerts.go

@@ -1,8 +1,8 @@
 // Package alerts sends alerts on bans, on traffic over an anomaly
 // threshold, on a source that fails and on a file with an error to each
 // destination set: to the webhook
-// SWWAF_ALERT_WEBHOOK_URL names, each as one JSON object, as "The JSON
-// object" in docs/alerts.md describes, to the Slack incoming
+// SWWAF_ALERT_WEBHOOK_URL names, each as one JSON object, as the "Alert
+// webhook schema" section of SPEC.md describes, to the Slack incoming
 // webhook SWWAF_ALERT_SLACK_WEBHOOK_URL names, as a message, and to the
 // ntfy topic SWWAF_ALERT_NTFY_URL names. A repeat within
 // SWWAF_ALERT_COOLDOWN is held back, and so is an alert past
@@ -149,10 +149,11 @@ type Params struct {
 }
 
 // Alert is one alert, as the webhook is sent it and alerts.json holds it,
-// with the fields of "The JSON object" in docs/alerts.md. ASN, ASName and
-// Country are, for a ban, the client's as the ban's notes give them.
+// with the fields of the "Alert webhook schema" section of SPEC.md. ASN,
+// ASName and Country are, for a ban, the client's as the ban's notes give
+// them.
 //
-//nolint:tagliatelle // docs/alerts.md names the alert's fields in snake_case
+//nolint:tagliatelle // SPEC.md's alert webhook schema names its fields in snake_case
 type Alert struct {
 	Instance string       `json:"instance"`
 	Time     time.Time    `json:"time"`

internal/anomaly/anomaly.go

@@ -1,8 +1,8 @@
 // Package anomaly counts requests and bytes over a minute and an hour, per
 // client, per surrounding netblock, per AS number, for the whole service
 // and per named netblock, and raises an anomaly alert for a count over its
-// threshold, as "Anomaly thresholds" under "Settings" in SPEC.md
-// describes. It refuses and bans nothing. At most 20,000 counters
+// threshold, as "Anomaly thresholds" under "Configuration surface" in
+// SPEC.md describes. It refuses and bans nothing. At most 20,000 counters
 // are kept, in memory, and written to alerts.json and read from it by the
 // state package.
 package anomaly

internal/config/config.go

@@ -502,17 +502,17 @@ func FromEnvironment(lookupEnv func(string) (string, bool)) (*Config, error) {
 		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"),
+		ResponseMaxBytes:        env.size("SWWAF_RESPONSE_MAX_BYTES", "5G"),
 		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", "6000"),
-		RateLimitPerHour:        env.count("SWWAF_RATE_LIMIT_PER_HOUR", "100000"),
-		RateLimitPerDay:         env.count("SWWAF_RATE_LIMIT_PER_DAY", "1000000"),
+		RateLimitPerMinute:      env.count("SWWAF_RATE_LIMIT_PER_MINUTE", "1000"),
+		RateLimitPerHour:        env.count("SWWAF_RATE_LIMIT_PER_HOUR", "10000"),
+		RateLimitPerDay:         env.count("SWWAF_RATE_LIMIT_PER_DAY", "50000"),
 		RateLimitExemptPaths:    env.pathPrefixes("SWWAF_RATE_LIMIT_EXEMPT_PATHS", ""),
-		BytesLimitPerMinute:     env.size("SWWAF_BYTES_LIMIT_PER_MINUTE", "4G"),
+		BytesLimitPerMinute:     env.size("SWWAF_BYTES_LIMIT_PER_MINUTE", "10G"),
 		BytesLimitPerHour:       env.size("SWWAF_BYTES_LIMIT_PER_HOUR", "20G"),
-		BytesLimitPerDay:        env.size("SWWAF_BYTES_LIMIT_PER_DAY", "200G"),
+		BytesLimitPerDay:        env.size("SWWAF_BYTES_LIMIT_PER_DAY", "50G"),
 		BytesCount:              env.bytesCount("SWWAF_BYTES_COUNT", "both"),
 		LookupSource:            env.lookupSource("SWWAF_LOOKUP_SOURCE", "geojs"),
 		LookupDBPath:            env.value("SWWAF_LOOKUP_DB_PATH", ""),

internal/config/config_test.go

@@ -261,10 +261,10 @@ func TestDefaults(t *testing.T) {
 		UpstreamRequestTimeout:      time.Minute,
 		UpstreamResponseTimeout:     30 * time.Minute,
 		RequestMaxBytes:             100 << 20,
-		ResponseMaxBytes:            1 << 30,
-		RateLimitPerMinute:          6000,
-		RateLimitPerHour:            100000,
-		RateLimitPerDay:             1000000,
+		ResponseMaxBytes:            5 << 30,
+		RateLimitPerMinute:          1000,
+		RateLimitPerHour:            10000,
+		RateLimitPerDay:             50000,
 		BanResponse:                 403,
 		LimitBanDuration:            time.Hour,
 		LimitBanRepeatWindow:        24 * time.Hour,
@@ -284,8 +284,8 @@ func TestDefaults(t *testing.T) {
 		LookupSource: defaultLookupSource, LookupTimeout: time.Second,
 	})
 	wantByteLimitSettings(t, cfg, config.Config{
-		BytesLimitPerMinute: 4 << 30, BytesLimitPerHour: 20 << 30,
-		BytesLimitPerDay: 200 << 30, BytesCount: "both",
+		BytesLimitPerMinute: 10 << 30, BytesLimitPerHour: 20 << 30,
+		BytesLimitPerDay: 50 << 30, BytesCount: "both",
 	})
 
 	if cfg.UpstreamURL.String() != "http://127.0.0.1:8081" {
@@ -2371,17 +2371,17 @@ func TestLogsEachSettingWithItsValue(t *testing.T) {
 		upstreamRequestTimeout:  "60s",
 		upstreamResponseTimeout: "30m",
 		requestMaxBytes:         "100M",
-		responseMaxBytes:        "1G",
+		responseMaxBytes:        "5G",
 		allowNets:               "",
 		rateLimitExemptNets:     "",
 		denyNets:                "",
-		rateLimitPerMinute:      "6000",
-		rateLimitPerHour:        "100000",
-		rateLimitPerDay:         "1000000",
+		rateLimitPerMinute:      "1000",
+		rateLimitPerHour:        "10000",
+		rateLimitPerDay:         "50000",
 		rateLimitExemptPaths:    "",
-		bytesLimitPerMinute:     "4G",
+		bytesLimitPerMinute:     "10G",
 		bytesLimitPerHour:       "20G",
-		bytesLimitPerDay:        "200G",
+		bytesLimitPerDay:        "50G",
 		bytesCount:              "both",
 		lookupSource:            defaultLookupSource,
 		lookupDBPath:            "",

internal/metrics/metrics.go

@@ -1,7 +1,6 @@
-// Package metrics keeps smallwebwaf's Prometheus metrics, as
-// docs/metrics.md lists them, and serves them in the Prometheus text
-// format, as the "Metrics endpoint" section of SPEC.md requires. No
-// metric carries a client's address.
+// Package metrics keeps smallwebwaf's Prometheus metrics, as the "Metrics
+// endpoint" section of SPEC.md lists them, and serves them in the
+// Prometheus text format. No metric carries a client's address.
 package metrics
 
 import (

internal/ratelimit/ratelimit.go

@@ -206,7 +206,7 @@ type Hit struct {
 // Counts are a client's requests and bytes in the minute, the hour and
 // the day that end at a request, that request's included.
 //
-//nolint:tagliatelle // docs/request-log.md names the fields in snake_case
+//nolint:tagliatelle // SPEC.md's request log names its fields in snake_case
 type Counts struct {
 	Minute      float64 `json:"minute"`
 	Hour        float64 `json:"hour"`

internal/requestlog/requestlog.go

@@ -64,10 +64,11 @@ const LimitHitErrorBurst = "error_burst"
 const timeLayout = "2006-01-02T15:04:05.000Z07:00"
 
 // Line is one request's line in the request log. The field names, and
-// their order, are those of docs/request-log.md. A field that may not
-// apply to a request is left out of its line when it does not.
+// their order, are those of the "Request log" section of SPEC.md. A field
+// that may not apply to a request is left out of its line when it does
+// not.
 //
-//nolint:tagliatelle // docs/request-log.md names the fields in snake_case
+//nolint:tagliatelle // SPEC.md's request log names its fields in snake_case
 type Line struct {
 	Type string `json:"type"`
 

internal/smallwebwaf/healthcheck_test.go

@@ -60,19 +60,8 @@ func TestHealthCheck(t *testing.T) {
 		}, 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: ")
+	app.Close()
+	wantHealthCheck(t, env, 1, "unhealthy: connect to the app: ")
 
 	stop()
 
@@ -81,6 +70,10 @@ func TestHealthCheck(t *testing.T) {
 	case <-time.After(waitLimit):
 		t.Fatal("still running after being told to stop")
 	}
+
+	wantHealthCheck(t, env, 1, "unhealthy: ask smallwebwaf: ")
+	wantHealthCheck(t, map[string]string{listenAddr: "8080"}, 1,
+		"unhealthy: invalid setting: SWWAF_LISTEN_ADDR: ")
 }
 
 func TestHealthCheckRefusesAnArgument(t *testing.T) {

internal/smallwebwaf/smallwebwaf_test.go

@@ -1240,13 +1240,13 @@ func wantStartingLine(t *testing.T, line map[string]any, appURL, dir string) {
 		"SWWAF_UPSTREAM_REQUEST_TIMEOUT":        "60s",
 		"SWWAF_UPSTREAM_RESPONSE_TIMEOUT":       "30m",
 		"SWWAF_REQUEST_MAX_BYTES":               "100M",
-		"SWWAF_RESPONSE_MAX_BYTES":              "1G",
+		"SWWAF_RESPONSE_MAX_BYTES":              "5G",
 		"SWWAF_ALLOW_NETS":                      "",
 		rateLimitExemptNets:                     "",
 		"SWWAF_DENY_NETS":                       "",
-		"SWWAF_RATE_LIMIT_PER_MINUTE":           "6000",
-		"SWWAF_RATE_LIMIT_PER_HOUR":             "100000",
-		rateLimitPerDay:                         "1000000",
+		"SWWAF_RATE_LIMIT_PER_MINUTE":           "1000",
+		"SWWAF_RATE_LIMIT_PER_HOUR":             "10000",
+		rateLimitPerDay:                         "50000",
 		"SWWAF_RATE_LIMIT_EXEMPT_PATHS":         "",
 		"SWWAF_DENIED_COUNTRIES":                "",
 		"SWWAF_EXCLUSIVELY_ALLOWED_COUNTRIES":   "",

internal/state/state.go

@@ -1,6 +1,5 @@
 // Package state keeps smallwebwaf's state in JSON files in
-// SWWAF_STATE_DIR, as the "Persistent state" section of SPEC.md requires
-// and docs/state-files.md lists them:
+// SWWAF_STATE_DIR, as the "Persistent state" section of SPEC.md describes:
 // bans.json holds the bans, clients.json each client's counters and
 // history, lookups.json GeoJS's answers, reputation.json the last try and
 // last good copy of each list fetched from a URL, the DNSBL zones'

internal/state/state_test.go

@@ -1019,8 +1019,8 @@ func TestEditJustBeforeAScheduledWriteSurvivesIt(t *testing.T) {
 		edit(t, dir, bansJSON, permanentBansJSON)
 
 		// The write takes the edit in first, and writes it back. The second
-		// ban, made after the admin opened the file, is lost, as the
-		// "Persistent state" section of SPEC.md says.
+		// ban, made after the admin opened the file, is lost, as "Edits
+		// while running" in SPEC.md says.
 		time.Sleep(time.Nanosecond)
 		synctest.Wait()
 

internal/waf/waf.go

@@ -1,8 +1,8 @@
 // Package waf runs the OWASP Core Rule Set 4.25.0, through Coraza, on the
 // method, the URL with its query and the headers of a request, and on its
 // body while SWWAF_WAF_BODY_LIMIT is set, with the six changes smallwebwaf
-// makes to it, as "Attack detection" under "Settings" in SPEC.md describes
-// them. It reads no response.
+// makes to it, as "Attack detection" under "Configuration surface" in
+// SPEC.md describes them. It reads no response.
 //
 // smallwebwaf writes only to its state directory, so Coraza is built with
 // its no_fs_access tag, as the Dockerfile and script/build build it: of a

script/gitea-requests

@@ -2,12 +2,11 @@
 # 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.
+# that reading gitea's source found the Core Rule Set refuses, 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.
 # 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,