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

@@ -30,9 +30,9 @@ 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 that runs those rules, inspects each
-  request the earlier checks let through. A request the rules take for an attack
-  is refused.
+  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;
     - give the clients of chosen networks and countries a fraction of every
@@ -132,8 +132,9 @@ docker run --detach --name app \
 
 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` looks addresses up in a database file on
-your own host (see "Lookup of AS number and country" in [`SPEC.md`](SPEC.md)).
+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)).
 
 `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
@@ -149,9 +150,10 @@ request that counts against its client in its history. It is one of:
 - a broken limit;
 - a refusal by a rule, by the Core Rule Set or for a missing or wrong token.
 
-`smallwebwaf` handles each request in this order. The first step that refuses it
-ends the handling. Nothing of a refused request reaches the app. "What happens
-to a request" in [`SPEC.md`](SPEC.md) gives each step in full.
+`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.
@@ -187,18 +189,18 @@ to a request" in [`SPEC.md`](SPEC.md) gives each step in full.
 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 the
-    body too once `SWWAF_WAF_BODY_LIMIT` is set. 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.
+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, the request's bytes are counted for the byte
-    limits. If a rule, a trap path, the Core Rule Set or a token check refused
-    it, 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.
+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
@@ -209,27 +211,32 @@ 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 without an answer.
-  It answers:
+  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.
-- `413` or `408` when the client passes a size or time limit, `502` or `504`
-  when the app does.
+- 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
 
+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:
 
 - `SWWAF_MODE=observe`: log what would have been refused, refuse almost nothing,
   ban no one. For trying a configuration.
-- `SWWAF_ALLOW_NETS`: netblocks whose clients are refused only for a size or
-  time limit or a missing or wrong token, such as your monitoring.
+- `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
@@ -237,7 +244,8 @@ values it takes. The ones most deployments touch:
   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.
+  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.
@@ -261,9 +269,8 @@ values it takes. The ones most deployments touch:
   `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` or through the
-  ban endpoint (see "Bans" in [`SPEC.md`](SPEC.md) and
-  [`docs/admin-endpoints.md`](docs/admin-endpoints.md)).
+  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.
@@ -285,8 +292,8 @@ the `Makefile` targets are thin shims that call them. The scripts are POSIX sh.
 The tests and the linter run in Docker, as phases of the `Dockerfile`, and never
 on the host.
 
-- `script/bootstrap`: installs what the other scripts need on the host.
-  `make bootstrap`. They need:
+- `script/bootstrap`: installs on the host what the other scripts need, with
+  `make bootstrap`:
     - `make`, `git` and `curl`;
     - Go, for `gofmt`;
     - node, yarn and prettier.
@@ -416,9 +423,9 @@ another port, the health check's timing, and the forwarded headers.
 
 ## TODO
 
-- Everything `SPEC.md` describes is built.
-- Two points `SPEC.md` defers until there is experience to go on: sharing bans
-  between the instances of several apps, and sending the log over RELP.
+- Planned, as "Planned, not built" in [`SPEC.md`](SPEC.md) describes:
+    - sharing bans between the instances of several apps;
+    - sending the log over RELP.
 
 ## Documents
 

docs/alerts.md

@@ -78,11 +78,14 @@ 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. `netblock`: the ban's
-  netblock, the netblock an anomaly counted, or, for the other events, the
-  client as rate limiting counts it: an IPv4 address as a /32, or an IPv6 group.
-  Both are empty for `source_failure` and `file_error`.
-- `asn`, `as_name` and `country`: the client's as known when the alert was
+- `client`: the address whose request raised the alert. Empty for
+  `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;
+    - 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 1000` or `listed by a blocklist`.

docs/gitea.md

@@ -21,10 +21,10 @@ checked again when gitea or the Core Rule Set changes version.
     - a release attachment.
 
     At the defaults, an upload larger than 100 MiB or taking more than 60
-    seconds is cut off, and no one is banned for it. "Size and time limits" in
-    `SPEC.md` gives the answers the client gets. A gitea that takes large
-    uploads needs `SWWAF_REQUEST_MAX_BYTES`, `SWWAF_CLIENT_REQUEST_TIMEOUT` and
-    `SWWAF_UPSTREAM_REQUEST_TIMEOUT` raised to fit.
+    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.
 
 - Archive download and blame or history pages are what scrapers hammer. The
   request limits do most of the work there.
@@ -63,15 +63,15 @@ toward). The request log names the rule in `waf_rule_ids`, which
 
 ### A query string that reads as an attack
 
-Most often this is a search. Every query parameter is checked against the Core
-Rule Set's lists of system files and commands, except the ten named under
-"Attack detection" in `SPEC.md`. A release attachment uploaded through the API
-as `docker-compose.yml` is refused the same way. Examples:
+Most often this is a search. A search term is a query parameter, which the Core
+Rule Set checks against its lists of system files and commands (see the fourth
+change under "Attack detection" in `SPEC.md`). A release attachment uploaded
+through the API as `docker-compose.yml` is refused the same way. Examples:
 
 - a name on those lists, such as `package.json`, `.gitignore` or
   `docker-compose.yml`;
-- text that starts with a command name, or whose first word has one right after
-  a `/`, such as `python3`, `ssh key` or `feat/docker-support`;
+- text that starts with a command name, such as `python3` or `ssh key`, or has
+  one right after a `/` in its first word, such as `feat/docker-support`;
 - a shell command with its options or a system path (`ls -la`, `sed -i`,
   `/bin/sh`), or a command in backticks;
 - script code (`fetch(`, `${VAR}`, `process.env`), HTML (`<img src=`) or an SQL
@@ -81,15 +81,15 @@ as `docker-compose.yml` is refused the same way. Examples:
 ### A branch, tag or file name that starts with a command name
 
 The Core Rule Set's list of commands (932260) holds names such as `docker-`,
-`python3`, `ansible`, `base64` and `whoami`. A branch, tag or file name that
-starts with one is refused. So is one that has such a name right after a `/`,
-such as `feat/docker-support`, `fix/docker-build` or
+`python3`, `ansible`, `base64` and `whoami`. A query parameter holding a branch,
+tag or file name that starts with one is refused. So is one that has such a name
+right after a `/`, such as `feat/docker-support`, `fix/docker-build` or
 `renovate/docker-build-push-action-6.x`. gitea's own pages send the name in a
 query parameter that 930120, 932160 and 932260 still check:
 
-- `refSubUrl`, the branch or tag of a directory listing. It is sent when the
-  listing asks for its entries' last commits in a second request, which it does
-  whenever gitea takes more than a second to work them out;
+- `refSubUrl`, the branch or tag of a directory listing. A listing sends it when
+  it asks for its entries' last commits in a second request. It does so whenever
+  gitea takes more than a second to work them out;
 - `name`, when a branch is deleted or restored on the branches page;
 - `tag`, when a release is started from a tag;
 - `template`, the file of an issue template, when an issue is opened from it;
@@ -110,9 +110,9 @@ What a visitor sees, for a branch named `docker-build`:
 ### A file name in a query parameter that trips the code rules
 
 The Core Rule Set's rules for Java, script, PowerShell and SQL find what they
-look for in some file names. This holds in the parameters `smallwebwaf` leaves
-out of 930120, 932160 and 932260 too (see the changes to the Core Rule Set under
-"Attack detection" in `SPEC.md`). Examples:
+look for in some file names. This holds too in the ten query parameters that
+930120, 932160 and 932260 do not check (see the fourth change under "Attack
+detection" in `SPEC.md`). Examples:
 
 - `runtime` in OpenJDK's `src/java.base/share/classes/java/lang/Runtime.java`
   (944110);
@@ -129,9 +129,9 @@ For such a file, these requests are refused:
 - the API's call for the contents of files that names it in its query (`body`);
 - the commit graph of that file alone (`file`);
 - the hidden lines of its diff (`path`), which stay hidden;
-- the sign-in page gitea sends a visitor to on the way to a page of the file
-  that needs signing in, such as its edit page (`redirect_to`). The visitor can
-  still sign in by opening the sign-in page itself.
+- the sign-in page, for a visitor who opens a page of the file that needs
+  signing in, such as its edit page (`redirect_to`). The visitor can still sign
+  in by opening the sign-in page itself.
 
 ### A path
 
@@ -143,25 +143,30 @@ For such a file, these requests are refused:
   `process.env.d.ts` does.
 - A path with a directory named `...` (930100, 930110), such as `.../notes.txt`.
 
-For such a file, the page of the file, its raw file, its history, its blame and
-its edit page are refused. The directory that holds it lists it, and a clone
-carries it.
+For such a file, these are refused:
+
+- the page of the file;
+- its raw file;
+- its history and its blame;
+- its edit page.
+
+The directory that holds it lists it, and a clone carries it.
 
 ### A container image push that reuses a layer
 
 A push can reuse a layer of an image docker has pushed to that gitea before.
 docker then asks gitea to take the layer from that image, naming it in the query
 parameter `from`, which 932260 checks. The request is refused when the image's
-owner starts with an entry on the list of commands. So is one whose name after
-the owner does. Examples are `owner/python3-app`, `owner/docker-base`, and any
-image of an owner named `ansible` or `docker-team`.
+owner starts with an entry on the list of commands. It is refused too when the
+image's name after the owner starts with one. Examples are `owner/python3-app`,
+`owner/docker-base`, and any image of an owner named `ansible` or `docker-team`.
 
 What happens next depends on docker's image store. A docker that keeps its
 images in containerd's image store fails the push, and fails each new try the
 same way. A new install of Docker Engine 29 does this. A docker that keeps them
 in its own older image store uploads the layer instead. The push then succeeds
 after one refusal for each layer it reuses, and each of those refusals counts
-toward the error burst.
+toward the error burst ("Attack detection" in `SPEC.md`).
 
 ### Artifact uploads from `actions/upload-artifact@v3`
 
@@ -169,9 +174,9 @@ This action sends the header `Content-Range`, which the Core Rule Set refuses
 (920450). The action sends two files at a time, does not retry a `403`, and
 sends no further file once one is refused. So an upload is refused once or
 twice, however many files it holds, and the step fails. One upload does not ban
-the runner. More than 30 such refusals from its address within a minute, as when
-many jobs upload at once, ban it through the error burst.
-`actions/upload-artifact@v4` does not send the header.
+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
 
@@ -193,8 +198,7 @@ Of the requests above, the script sends:
   code rules", the API's list of its commits;
 - for `Runtime.java` alone, the commit graph of that file, the hidden lines of
   its diff, and the API's call for the contents of files that names it;
-- the sign-in page gitea sends a visitor to on the way to the edit page of
-  `document.write.js`;
+- the sign-in page for a visitor who opens the edit page of `document.write.js`;
 - the pages of `java.lang.String.md`,
   `META-INF/services/org.apache.commons.logging.LogFactory`, `process.env.d.ts`
   and `.../notes.txt`;

docs/image.md

@@ -31,6 +31,7 @@ is pinned that way.
 - nixpkgs: the release file `nixexprs.tar.xz` of
   `nixos-26.05.11045.774debe7a0d1` on `releases.nixos.org`, named with its
   SHA-256 hash.
-- `runsvinit`: the archived repository, unchanged since 2015, at tag `v2.0.0`,
-  by commit hash, with a `go.mod` the build writes.
+- `runsvinit`: the archived repository, unchanged since 2015, at its last commit
+  (`b4b2c78`, eight commits after `v2.0.0`), by commit hash, with a `go.mod` the
+  build writes.
 - The Go image that builds `smallwebwaf`: by digest.

docs/metrics.md

@@ -1,10 +1,8 @@
 # The metrics
 
-`GET /_smallwebwaf/metrics` answers in the Prometheus text format. The
-requirements are under "Metrics endpoint" in [`SPEC.md`](../SPEC.md); this file
-lists the metrics. Every metric carries the label `instance`, set to
-`SWWAF_INSTANCE_NAME`; Prometheus keeps it as `exported_instance` unless the
-scrape sets `honor_labels: true`. No metric carries a client's address.
+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/request-log.md

@@ -12,9 +12,13 @@ sent to a syslog server. A field that does not apply to a request is left out.
 
 ## Every line
 
-Every line has `type` (`request`; the process's own messages have `process`),
-the standard web log fields, `request_id`, `peer_ip`, `client_group`, `asn`,
-`as_name`, `country`, `action` and `duration_total`.
+Every line 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
 
@@ -28,7 +32,7 @@ the standard web log fields, `request_id`, `peer_ip`, `client_group`, `asn`,
 ## Request detail
 
 - `request_id`: the `X-Request-ID` a trusted proxy sent, or a new random one of
-  26 letters and digits. It goes to the app in `X-Request-ID`.
+  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
@@ -73,15 +77,22 @@ the standard web log fields, `request_id`, `peer_ip`, `client_group`, `asn`,
   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. A count
-  can have a fraction, since each window is counted in two buckets with the
-  earlier one weighted:
+  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.
-- `limit_hit`: the limit broken: `minute`, `hour` or `day` for a rate limit;
-  `minute_bytes`, `hour_bytes` or `day_bytes` for a byte limit; or
-  `error_burst`. A request whose bytes broke a limit was passed on whole, so its
-  `action` stays `forward`.
+
+    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
@@ -91,7 +102,7 @@ the standard web log fields, `request_id`, `peer_ip`, `client_group`, `asn`,
     - the CrowdSec decision list's URL;
     - DNS blocklist zones;
     - `abuseipdb`.
-- `offence`: the kind of offence recorded, when one was.
+- `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`.
 

docs/settings.md

@@ -2,8 +2,7 @@
 
 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. A setting
-set to a value its entry does not allow stops the start.
+that take `off`, the `_FILE` form, and what each group does and why.
 
 ## Forms of values
 
@@ -27,8 +26,9 @@ set to a value its entry does not allow stops the start.
 
 - `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, an
-  optional host and a port. The host stays empty.
+- `SWWAF_LISTEN_ADDR` (default `:8080`): where `smallwebwaf` 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
@@ -42,8 +42,8 @@ set to a value its entry does not allow stops the start.
   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`): the most bans `smallwebwaf` made that are
-  kept, a whole number above zero.
+- `SWWAF_MAX_BANS` (default `5000`): how many of its own bans `smallwebwaf`
+  keeps, a whole number above zero.
 
 ## Tokens
 
@@ -90,8 +90,9 @@ set to a value its entry does not allow stops the start.
 
 ## Static lists
 
-- `SWWAF_ALLOW_NETS` (default empty): netblocks whose clients are refused only
-  for a size or time limit or a missing or wrong token, such as your monitoring.
+- `SWWAF_ALLOW_NETS` (default empty): 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` (default empty): netblocks whose clients are
   exempt from rate limiting and the byte limits.
 - `SWWAF_DENY_NETS` (default empty): netblocks whose clients are always refused.
@@ -150,7 +151,7 @@ set to a value its entry does not allow stops the start.
   such as `cn,ru,kp`.
 - `SWWAF_EXCLUSIVELY_ALLOWED_COUNTRIES` (default empty): when set, the only
   countries whose clients get through, such as `us,de`. A country on both lists
-  is refused.
+  stops the start.
 
 ## Biased thresholds
 
@@ -164,8 +165,8 @@ set to a value its entry does not allow stops the start.
 - `SWWAF_UNKNOWN_LIMIT_PERCENT` (default `100`): the percentage for a client the
   lookup cannot place.
 - `SWWAF_ASN_LIMIT_PERCENT_URL` (default unset): the `http` or `https` URL of a
-  text file of `AS<number>:<percent>` lines, one to a line. A URL that is also
-  in `SWWAF_BLOCKLIST_URLS` is refused.
+  text file with one AS number and percentage on each line, such as
+  `AS64496:50`. A URL that is also in `SWWAF_BLOCKLIST_URLS` is refused.
 
 ## Attack detection
 
@@ -260,8 +261,8 @@ set to a value its entry does not allow stops the start.
   `ban,permanent_ban,waf_block,anomaly,reputation_hit,source_failure,file_error`):
   the event types alerts are sent for, from those in [`alerts.md`](alerts.md)
   but `summary`. Any other name is refused.
-- `SWWAF_ALERT_COOLDOWN` (default `15m`): how long a repeat of an alert is held
-  back. A duration or `off`.
+- `SWWAF_ALERT_COOLDOWN` (default `15m`): how long after an alert is sent its
+  repeats are held back. A duration or `off`.
 - `SWWAF_ALERT_MAX_PER_HOUR` (default `60`): the most alerts sent in an hour. A
   whole number above zero, or `off`.
 
@@ -294,10 +295,8 @@ as `REQUESTS_PER_MINUTE`:
 
 ## Settings given as files
 
-Add `_FILE` to a setting's name to read its value from a file:
-`SWWAF_METRICS_TOKEN_FILE` names the file that holds `SWWAF_METRICS_TOKEN`. To
-keep a token from the app, make the file on the host, owned by uid 65532 with
-mode `0400`:
+To give a token as a file, as "Tokens" under "Deployment" in
+[`SPEC.md`](../SPEC.md) describes, make the file on the host:
 
 ```sh
 mkdir -p /srv/app/tokens
@@ -306,7 +305,7 @@ chown 65532:65532 /srv/app/tokens/metrics
 chmod 0400 /srv/app/tokens/metrics
 ```
 
-Mount its directory into the container read-only, and name the file:
+Then mount its directory into the container read-only, and name the file:
 
 ```sh
 docker run \

docs/state-files.md

@@ -15,8 +15,8 @@ those `smallwebwaf` made. Per entry:
 - `lifted`: when an admin lifted it, if one did;
 - `notes`: the notes below.
 
-To ban a netblock, add an entry with its `netblock`, `start` and `expires`.
-`reason`, `notes` and `cause` may be left out; the cause is then `admin`:
+An entry an admin adds needs `netblock`, `start` and `expires`; `reason`,
+`notes` and `cause` may be left out, and the cause is then `admin`:
 
 ```json
 {
@@ -32,20 +32,23 @@ To ban a netblock, add an entry with its `netblock`, `start` and `expires`.
 }
 ```
 
-To lift a ban, add `"lifted"` with the time you lift it, such as
-`"lifted": "2026-10-06T13:00:00Z"`. To keep a ban `smallwebwaf` made, set its
-`cause` to `admin`. To forget a ban, delete its entry.
-
-The notes:
+"Bans" in [`SPEC.md`](../SPEC.md) says how an edit lifts, keeps or forgets a
+ban. The notes:
 
 - `asn`, `as_name` and `country`: the client's, added when the lookup answers
   (empty when lookups are off);
-- what was broken: the rule id and target that matched, or the trap path, or the
-  limit, its window and the count reached;
-- the client's percentage of the limit, with the setting that gave it;
-- the reputation sources the client is on;
-- `request`: the request that caused the ban: time, method, host, path with its
-  query string, status and user agent, each text cut to 256 bytes;
+- for a broken limit, `kind` (`requests`, `bytes` or `refusals`), `limit`,
+  `window` and `count`: what the limit was on, the limit, its window and the
+  count reached;
+- `limit_percent` and `limit_percent_setting`: the client's percentage of that
+  limit and the setting that gave it, when a setting lowered it;
+- for a clear sign of attack, `rule_id` and `target`, or `trap_path`;
+- `reputation`: the sources the client was on, each with its `source` and, for
+  AbuseIPDB, its `score`;
+- `request`: the request that caused the ban, each text cut to 256 bytes:
+    - `time`, `method` and `host`;
+    - `path`, with its query string;
+    - `status` and `user_agent`;
 - `requests` and `refused`: the netblock's requests since it was first seen, and
   how many this ban has refused so far, kept up to date while the ban lasts;
 - `earlier_bans`: how many earlier bans the netblock had, by cause.
@@ -93,8 +96,9 @@ GeoJS answers, one per line:
   `SWWAF_MAX_TRACKED_CLIENTS`. Written every 15 minutes, that is under 2 GiB of
   disk writes a day.
 - `bans.json`: about 1.2 KiB per ban, at most about 2.5 KiB, so about 6 MiB at
-  the default `SWWAF_MAX_BANS`. With a full file, a hundred new bans a day come
-  to about 600 MiB of writes.
+  the default `SWWAF_MAX_BANS`. Written every 15 minutes, a full file comes to
+  about 600 MiB of writes a day, and a hundred new bans a day add about 600 MiB
+  more.
 - `lookups.json`: about 150 bytes per answer, under 1.5 GiB of writes a day when
   full.
 - `reputation.json` and `alerts.json`: usually a few MiB or less.