waf: decide every visitor request within rproxy's timeout (closes #394)

The Core Rule Set is the one check whose time a visitor can stretch.
At paranoia level 4 it took over 2 s on a request with an 8 KiB
request line, three 8 KiB Cookie lines and a 64 KiB form body.
SWW_WAF_CORE_RULE_SET_BODY_INSPECTION_SIZE now takes at most 8K. The
Core Rule Set also reads no JSON body over 1 KiB, since Coraza turns
JSON into up to 8 times its size in names and values. That brings
such a request under 1 s.

A test per kind of input times the Core Rule Set on the worst request
within the limits, at the slowest settings. SPEC.md lists the limits
that bound it.

Model: opus-5-5

README.md

@@ -2,7 +2,20 @@
 
 `smallwebwaf` is an MIT-licensed web application firewall, written in Go by
 [@sneak](https://sneak.berlin), for self-hosted web apps. It refuses the
-requests of scrapers, scanners and other abusers before they reach an app.
+requests of misbehaving scrapers, scanners and other abusers before they reach
+an app.
+
+With the default settings, a client is banned when it does any of these:
+
+- makes more than 120 requests in a minute, 1500 in an hour or 6000 in a day;
+- moves more than `50G` of request and response bodies in an hour, or `100G` in
+  a day;
+- asks for a secret or backup file, such as `/.env` or `/.git/config`;
+- sends a user agent that names a security scanner, such as `sqlmap` or `nikto`;
+- has more than 30 requests in a minute refused as probes or attacks.
+
+A scraper that does none of these is left alone. A scraper that waits 15 seconds
+between requests stays under the rate limits.
 
 ## What it does
 
@@ -10,10 +23,10 @@ A web application firewall reads each request on its way to a web app and
 refuses the ones that look like abuse. `smallwebwaf` is one program, `sww`,
 shipped in one image, with two commands that do this together:
 
-- `sww rproxy` is a small reverse proxy in front of one app. traefik routes to
-  it. It asks `waf` about each request, passes the allowed ones to the app, and
-  passes the app's answers back. It keeps nothing between requests and writes
-  nothing to disk.
+- `sww rproxy` is a small reverse proxy in front of one app. It sits behind a
+  TLS-terminating proxy, such as traefik, nginx or Caddy. It asks `waf` about
+  each request, passes the allowed ones to the app, and passes the app's answers
+  back. It writes nothing to disk.
 - `sww waf` decides. It runs the checks and keeps the bans, the counters and
   each client's history. One `waf` serves many sites: a client banned through
   one site is refused on all of them, and its requests on all of them count
@@ -22,7 +35,26 @@ shipped in one image, with two commands that do this together:
 The site keeps answering while `waf` is down, slow or restarting: without an
 answer in time, `rproxy` passes the request to the app.
 
-It protects against:
+`rproxy` also protects the app on its own, whether or not `waf` answers. With
+the default settings, `rproxy`:
+
+- answers `400` to a malformed request, such as a broken header line or a
+  missing `Host`;
+- answers `405` to a method it does not pass on, such as `TRACE`;
+- answers `431` to a request line and headers over 32 KiB together;
+- gives the visitor 60 seconds to send the request line and headers, and then 60
+  seconds more for the whole request to reach the app;
+- answers `413` to a request body over 100 MiB;
+- gives the app's answer 30 minutes to reach the visitor, counted from the end
+  of the request;
+- answers `502` in place of an app's answer whose body is over 1 GiB, or cuts it
+  off if it has started;
+- closes a kept-open connection after 120 seconds idle.
+
+`rproxy` does not limit the number of headers. `waf` limits the number of
+headers and cookies, and the length of the request line and of each header line.
+
+Together, `rproxy` and `waf` protect against:
 
 - Scrapers that fetch every page of a site, all day. Each client gets a limit on
   requests and on body bytes per minute, per hour and per day. The defaults
@@ -43,10 +75,7 @@ It protects against:
     - 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, 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
-  and a size limit.
+      AbuseIPDB score.
 
 For the operator, it:
 
@@ -58,8 +87,7 @@ For the operator, it:
 
 Not built, and not planned:
 
-- TLS and routing by host name. Both stay with traefik, the reverse proxy in
-  front of `rproxy`.
+- TLS and routing by host name. Both stay with the TLS-terminating proxy.
 - Browser challenges such as captchas.
 - A web console, or a configuration file.
 - Defence against floods large enough to fill the host's network link.
@@ -91,20 +119,61 @@ accepts connections, whether or not `waf` answers; in `waf`'s container, once
 The usual setup is three containers on one private network:
 
 - the app;
-- `rproxy`, in front of the app, which traefik routes to:
+- `rproxy`, in front of the app, which the TLS-terminating proxy forwards to:
   `SWW_RPROXY_WAF_BACKEND` names `waf` and `SWW_RPROXY_UPSTREAM_URL` names the
   app;
 - `waf`, with `SWW_COMMAND=waf` and a volume at `/var/lib/sww` 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 `waf`. Anything on that network can reach the app around
-`rproxy`, and can ask `waf` questions, so the network holds only what you trust.
-Each further app adds its own container and its own `rproxy`, whose
+Publish no port of the app or of `waf`. Anything on that network can reach the
+app around `rproxy`, and can ask `waf` questions, so the network holds only what
+you trust. Each further app adds its own container and its own `rproxy`, whose
 `SWW_RPROXY_WAF_BACKEND` names the same `waf`. The "Smallest setup" example
 below shows this shape.
 
+### The TLS-terminating proxy
+
+`rproxy` serves plain HTTP. It runs behind any TLS-terminating proxy, such as
+traefik, nginx or Caddy. The TLS-terminating proxy must:
+
+- forward each request to port 8080 of `rproxy` over plain HTTP;
+- keep the visitor's `Host` header;
+- add the visitor's address to `X-Forwarded-For`;
+- set `X-Forwarded-Proto` to the scheme the visitor used;
+- close an unused connection to `rproxy` in under 120 seconds;
+- connect to `rproxy` from an address in `SWW_RPROXY_TRUSTED_PROXIES`, by
+  default `10.0.0.0/8`, `172.16.0.0/12` or `192.168.0.0/16`.
+
+From any other address, `rproxy` ignores the forwarded headers and takes the
+TLS-terminating proxy for the visitor. Every visitor then shares one address,
+and one ban.
+
+traefik and Caddy keep the `Host` header and set both forwarded headers by
+default. traefik's Docker label
+`traefik.http.services.<name>.loadbalancer.server.port=8080` names the port.
+Caddy keeps an unused connection for 120 seconds by default, so its site
+shortens that to 90 seconds:
+
+```caddyfile
+reverse_proxy rproxy:8080 {
+    transport http {
+        keepalive 90s
+    }
+}
+```
+
+By default nginx sends the host in `proxy_pass` as `Host` and sets neither
+forwarded header, so its site sets all three:
+
+```nginx
+location / {
+    proxy_pass http://rproxy:8080;
+    proxy_set_header Host $host;
+    proxy_set_header X-Forwarded-For $proxy_add_x_forwarded_for;
+    proxy_set_header X-Forwarded-Proto $scheme;
+}
+```
+
 ### `rproxy` in the app's container
 
 An app's image can instead be built on the `smallwebwaf` image, so that `rproxy`
@@ -155,13 +224,13 @@ entrypoint starts `rproxy` and the app side by side, each as its own user. Run
 the app's image with `SWW_RPROXY_WAF_BACKEND` set. `deploy/example-app` is such
 an app, and the "`rproxy` beside the app" example below runs one.
 
-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.
+The app's TCP peer is `rproxy`. The app sees the headers the TLS-terminating
+proxy sent, with that proxy's address added to `X-Forwarded-For`. 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.
 
 ### Checking that it works
 
@@ -169,7 +238,7 @@ does.
   `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.
+- A request to the site through the TLS-terminating proxy gets the app's answer.
   `https://<site>/_sww/healthz` answers `ok`. `waf`'s log lines about the
   request have `"action":"forward"`.
 - To see a refusal without banning yourself, run `waf` with
@@ -229,7 +298,7 @@ Every setting the code reads, with its default:
 | `SWW_RPROXY_LISTEN_ADDR`                          | `:8080`                                                                                  | Where `rproxy` listens; leave the host part empty.                                                                                                                                                                                                              |
 | `SWW_RPROXY_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.                                                                                                                                                                       |
 | `SWW_RPROXY_WAF_BACKEND_TIMEOUT_MS`               | `2000`                                                                                   | How long `rproxy` waits for `waf`'s answer to a question and to a report, in milliseconds.                                                                                                                                                                      |
-| `SWW_RPROXY_WAF_BACKEND_NO_ANSWER_DISPOSITION`    | `allow`                                                                                  | What `rproxy` does with a request when `waf` cannot be reached or does not answer in time: `allow` passes it to the app, `deny` answers `503`.                                                                                                                  |
+| `SWW_RPROXY_WAF_BACKEND_NO_ANSWER_DISPOSITION`    | `allow`                                                                                  | What `rproxy` does with a request when `waf` gives no answer in time, and while the circuit breaker for asks to `waf` is open: `allow` passes it to the app, `deny` answers `503`.                                                                              |
 | `SWW_RPROXY_MAX_REQUEST_SIZE`                     | `100M`                                                                                   | The largest request body, a size or `off`; a larger one is answered `413`.                                                                                                                                                                                      |
 | `SWW_RPROXY_MAX_RESPONSE_SIZE`                    | `1G`                                                                                     | The largest response body, a size or `off`. The visitor gets `502` in place of a larger one, or it is cut off if it has already started.                                                                                                                        |
 | `SWW_RPROXY_MAX_REQUEST_TIME_MS`                  | `60000`                                                                                  | Two time limits, each this long, in milliseconds or `off`: one for the visitor to send its request line and headers, then one for the whole request to reach the app.                                                                                           |
@@ -261,7 +330,7 @@ Every setting the code reads, with its default:
 | `SWW_WAF_LOOKUP_SOURCE`                           | `geojs`                                                                                  | Where each client's AS number and country come from: `geojs` (a web service), `file` (a local database) or `off`.                                                                                                                                               |
 | `SWW_WAF_LOOKUP_DB_PATH`                          | empty                                                                                    | The IPinfo Lite database file, in its `.mmdb` form, read while the source is `file`.                                                                                                                                                                            |
 | `SWW_WAF_ASN_AND_COUNTRY_LOOKUP_TIMEOUT_MS`       | `800`                                                                                    | 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, in milliseconds.                                                                                                                |
-| `SWW_WAF_ADD_LOOKUP_HEADERS`                      | `false`                                                                                  | `true` passes the app the client's AS number and country in `X-Client-ASN` and `X-Client-Country`.                                                                                                                                                              |
+| `SWW_WAF_ADD_LOOKUP_HEADERS`                      | `true`, or `false` while the lookup source is `off`                                      | `true` passes the app the client's AS number and country in `X-Client-ASN` and `X-Client-Country`.                                                                                                                                                              |
 | `SWW_WAF_EXCLUSIVELY_ALLOWED_COUNTRIES`           | empty                                                                                    | When set, the only countries whose clients get through; a client the lookup cannot place is refused too.                                                                                                                                                        |
 | `SWW_WAF_TAG_LISTS`                               | empty                                                                                    | Address lists that each add a tag to their clients' requests, as `name=URL` pairs, such as `torexit=https://example.com/tor.txt`.                                                                                                                               |
 | `SWW_WAF_TAG_DENY`                                | empty                                                                                    | Tags whose requests are refused, such as `torexit,country=CN`.                                                                                                                                                                                                  |
@@ -279,7 +348,7 @@ Every setting the code reads, with its default:
 | `SWW_WAF_CORE_RULE_SET_SCORE_THRESHOLD`           | `5`                                                                                      | The Core Rule Set score at which a request is a match, a whole number or `off`; one critical rule scores 5.                                                                                                                                                     |
 | `SWW_WAF_CORE_RULE_SET_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.                                                                                                                                                |
 | `SWW_WAF_CORE_RULE_SET_EXEMPT_PATHS`              | empty                                                                                    | Path prefixes the Core Rule Set does not inspect.                                                                                                                                                                                                               |
-| `SWW_WAF_CORE_RULE_SET_BODY_INSPECTION_SIZE`      | `off`                                                                                    | How much of a request body the Core Rule Set reads, a size up to `64K`; `off` reads none.                                                                                                                                                                       |
+| `SWW_WAF_CORE_RULE_SET_BODY_INSPECTION_SIZE`      | `off`                                                                                    | How much of a request body the Core Rule Set reads, a size up to `8K`; `off` reads none.                                                                                                                                                                        |
 | `SWW_WAF_CORE_RULE_SET_EXCLUSIONS_FILE`           | unset                                                                                    | A file of Core Rule Set exclusions, as Coraza directives, that switch rules off for some fields or paths only.                                                                                                                                                  |
 | `SWW_WAF_APPS`                                    | unset                                                                                    | The apps each hostname serves, such as `git.example.com:gitea;blog.example.com:wordpress`; only those apps' fixes apply there. "Attack detection" lists the apps. Listing `forgejo` brings gitea's fixes too. Unset, every app's fixes apply to every hostname. |
 | `SWW_WAF_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`.                                                                                                                                     |
@@ -290,8 +359,6 @@ Every setting the code reads, with its default:
 | `SWW_WAF_ABUSEIPDB_KEY`                           | unset                                                                                    | The key of your AbuseIPDB account; set, a client that has committed an offence is checked in the background.                                                                                                                                                    |
 | `SWW_WAF_ABUSEIPDB_MIN_SCORE`                     | `75`                                                                                     | The least AbuseIPDB abuse confidence score, from 0 to 100, that is a hit.                                                                                                                                                                                       |
 | `SWW_WAF_ABUSEIPDB_DAILY_BUDGET`                  | `900`                                                                                    | The most AbuseIPDB checks made in a day.                                                                                                                                                                                                                        |
-| `SWW_WAF_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.                                                                                                         |
-| `SWW_WAF_CROWDSEC_LAPI_KEY`                       | unset                                                                                    | The key the engine gave for `smallwebwaf`, as `cscli bouncers add smallwebwaf` prints it; set with the URL, never alone.                                                                                                                                        |
 | `SWW_WAF_DNSBL_ABUSEIPDB_ACTION`                  | `limit:25`                                                                               | What a client listed by a DNS blocklist, or scored a hit by AbuseIPDB, gets: `deny`, `limit:<percent>` or `log`.                                                                                                                                                |
 | `SWW_WAF_IP_REPUTATION_CACHE_TTL`                 | `24h`                                                                                    | How long a DNS blocklist verdict or an AbuseIPDB score is used.                                                                                                                                                                                                 |
 | `SWW_WAF_DNSBL_ABUSEIPDB_TIMEOUT_MS`              | `2000`                                                                                   | How long a DNS blocklist query or an AbuseIPDB check may take, in milliseconds.                                                                                                                                                                                 |
@@ -543,9 +610,10 @@ request reaches the app.
 A refused visitor is answered with `SWW_WAF_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 `SWW_WAF_REFUSALS_LIMIT_PER_MINUTE`
-instead. A request over the header limits of step 3 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.
+instead. A request over the header limits of step 3 is answered `414` for a
+request line over 8 KiB and `431` otherwise. It 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.
 
 ### Clients and bans
 
@@ -570,8 +638,7 @@ Each request gets tags from what `waf` knows of its client, written in the
 - `asn=<number>` and `country=<code>`, from the lookup;
 - one tag per list of `SWW_WAF_TAG_LISTS` that holds the client, such as
   `torexit` or `vpn=mullvad`;
-- `crowdsec`, `dnsbl=<zone>` and `abuseipdb`, when that reputation source lists
-  the client;
+- `dnsbl=<zone>` and `abuseipdb`, when that reputation source lists the client;
 - `exploitsignature`, when a rule file or the Core Rule Set matched the request;
 - `asn=<number>` and `prefix=<netblock>`, from a routewatch instance, while
   `SWW_WAF_ROUTEWATCH_URL` is set.

SPEC.md

@@ -3,7 +3,7 @@
 `smallwebwaf` is a web application firewall for self-hosted apps. It is one
 binary, `sww`, and two of its commands do the work:
 
-- `sww rproxy` is a reverse proxy between traefik and one app.
+- `sww rproxy` is a reverse proxy between a TLS-terminating proxy and one app.
 - `sww waf` decides what happens to each request, for many sites.
 
 This document says what it must do and why, each requirement once. Everything in
@@ -45,7 +45,8 @@ never as a time.
 
 ## Non-goals
 
-- TLS, certificates and routing by host name. Those are traefik's job.
+- TLS, certificates and routing by host name. Those are the job of the
+  TLS-terminating proxy, such as traefik, nginx or Caddy.
 - More than one app behind one `rproxy`. Each app has its own.
 - Browser challenges such as captchas or proof of work. If wanted, chain Anubis
   between `rproxy` and the app.
@@ -151,32 +152,31 @@ field gives that name. `refusal_limit` and `byte_limits` give theirs in
       around its address, a /64 by default, since one abuser usually controls a
       whole /64. A client is therefore one IPv4 address or one IPv6 group.
 3. The header limits (`header_limits`; see "Answering in time"). They come first
-   after `SWW_WAF_ALLOW_NETS`, since they only count header fields and cookies.
-   Next, the tag lists (`tag_lists`; see "Request tags"). Each list that holds
-   the client adds its tag. Next, `routewatch_tags` adds the client's `asn=` and
-   `prefix=` tags while `SWW_WAF_ROUTEWATCH_URL` is set. A client in
-   `SWW_WAF_ALLOW_NETS` skips the header limits and gets no tag.
+   after `SWW_WAF_ALLOW_NETS`, since they only measure lines and count header
+   fields and cookies. Next, the tag lists (`tag_lists`; see "Request tags").
+   Each list that holds the client adds its tag. Next, `routewatch_tags` adds
+   the client's `asn=` and `prefix=` tags while `SWW_WAF_ROUTEWATCH_URL` is set.
+   A client in `SWW_WAF_ALLOW_NETS` skips the header limits and gets no tag.
 4. The static lists. A client in `SWW_WAF_ALLOW_NETS` skips steps 5 to 15, the
    byte limits and the refusal limit. A client in `SWW_WAF_DENY_NETS` is refused
    (`deny_nets`); a client in both lists is let through.
 5. Bans. A client under a ban is refused (`active_ban`; see "Bans").
 6. The lookup, unless `SWW_WAF_LOOKUP_SOURCE` is `off` (see "Lookup of AS number
-   and country"). The request goes on at once. It waits for the first GeoJS
-   answer, up to `SWW_WAF_ASN_AND_COUNTRY_LOOKUP_TIMEOUT_MS`, only when one of
-   these needs it:
+   and country"). The request waits for the first GeoJS answer, up to
+   `SWW_WAF_ASN_AND_COUNTRY_LOOKUP_TIMEOUT_MS`, when one of these needs it:
+    - `SWW_WAF_ADD_LOOKUP_HEADERS`, which is `true` by default;
     - the country list;
     - a biased threshold;
     - `SWW_WAF_TAG_DENY` or `SWW_WAF_TAG_LIMIT_PERCENT` naming an `asn=` or
-      `country=` tag;
-    - `SWW_WAF_ADD_LOOKUP_HEADERS`.
+      `country=` tag.
 
-    A request that ends before the answer comes is logged without it.
+    Otherwise the request goes on at once. A request that ends before the answer
+    comes is logged without it.
 
 7. The country list (`countries`; see "Country list").
 8. The reputation sources (see "Reputation"), in this order:
     - A client on a fetched blocklist gets `SWW_WAF_BLOCKLIST_ACTION`
       (`blocklists`).
-    - A client on the CrowdSec decision list is banned (`crowdsec`).
     - A client listed by a DNS blocklist gets `SWW_WAF_DNSBL_ABUSEIPDB_ACTION`
       (`dnsbl`).
     - A client scored at least `SWW_WAF_ABUSEIPDB_MIN_SCORE` by AbuseIPDB gets
@@ -198,10 +198,10 @@ field gives that name. `refusal_limit` and `byte_limits` give theirs in
 16. A path under `/_sww/` is answered `404`, so that the app never sees that
     prefix.
 17. `rproxy` passes the request to `SWW_RPROXY_UPSTREAM_URL`, streaming (see
-    "Passing a request to the app"). With `SWW_WAF_ADD_LOOKUP_HEADERS`,
-    `X-Client-ASN` and `X-Client-Country` are added for the app's own logs; a
-    header whose value is unknown is left out. Whatever that setting says, any
-    such header the client sent is removed.
+    "Passing a request to the app"). While `SWW_WAF_ADD_LOOKUP_HEADERS` is
+    `true`, as by default, `X-Client-ASN` and `X-Client-Country` are added for
+    the app's own logs; a header whose value is unknown is left out. Whatever
+    that setting says, any such header the client sent is removed.
 18. After the visitor's answer has ended, `rproxy` sends the report (see "The
     report"). `waf` then counts:
     - For a request it allowed, the body bytes of the response, of the request
@@ -253,9 +253,9 @@ does not reach neighbours who did nothing. Requests refused under a ban are not
 counted against limits. They are counted in the client's history and in the
 ban's notes.
 
-A request over the header limits is refused with `431` before the bans are
-checked (see "Answering in time"). It makes no ban, makes no ban permanent and
-is not counted in a ban's notes.
+A request over the header limits is refused with `414` or `431` before the bans
+are checked (see "Answering in time"). It makes no ban, makes no ban permanent
+and is not counted in a ban's notes.
 
 An offence is a request `waf` holds against the client. It is one of:
 
@@ -301,14 +301,6 @@ without a ban, because the Core Rule Set has false positives. A `block` rule
 does the same. Those refusals count toward the refusal limit, so a client that
 keeps setting them off is banned for a broken limit.
 
-A client on the CrowdSec decision list is banned until the decision ends, with
-the cause `crowdsec`. Only a client that sends a request is banned, so a long
-list does not fill `bans.json`. Such a ban is never made permanent. It does not
-make the netblock's next ban for a broken limit longer. A ban lifted while the
-decision is in force is made again at the client's next request. To lift it for
-good, delete the decision in CrowdSec, then lift the ban once the list has been
-fetched again.
-
 These refuse each request they cover, record nothing in `bans.json`, and count
 no offence:
 
@@ -338,10 +330,10 @@ toward `SWW_WAF_MAX_BANS`, so such bans can never fill the table.
 
 A request refused under a ban that runs out is logged with the action
 `temporarily_banned`. Under a permanent ban the action is `permanently_banned`.
-A request refused for a clear sign of attack or a CrowdSec decision takes the
-action for the ban it made. A request that makes a ban permanent is logged as
-`permanently_banned`. A request over a rate limit is logged as
-`client_is_rate_limited`, whichever ban it makes.
+A request refused for a clear sign of attack takes the action for the ban it
+made. A request that makes a ban permanent is logged as `permanently_banned`. A
+request over a rate limit is logged as `client_is_rate_limited`, whichever ban
+it makes.
 
 ## Settings
 
@@ -575,9 +567,9 @@ Each tag and where it comes from:
 - One tag per list of `SWW_WAF_TAG_LISTS` that holds the client (`tag_lists`),
   the tag being the list's name, such as `torexit` or `vpn=mullvad`. These lists
   are fetched and kept like a blocklist. `waf` ships none of its own.
-- `crowdsec`, `dnsbl=<zone>` and `abuseipdb`, when that reputation source lists
-  the client, whatever the source's action. A zone with a key is named with the
-  key masked, as the `reputation` field gives it.
+- `dnsbl=<zone>` and `abuseipdb`, when that reputation source lists the client,
+  whatever the source's action. A zone with a key is named with the key masked,
+  as the `reputation` field gives it.
 - `exploitsignature`, when a rule file or the Core Rule Set matched the request.
   For the Core Rule Set a match is a score at or over
   `SWW_WAF_CORE_RULE_SET_SCORE_THRESHOLD`.
@@ -712,11 +704,12 @@ files, the limits and the bans still apply to the client that sends it.
       rules is loaded yet.
 
 - `SWW_WAF_CORE_RULE_SET_BODY_INSPECTION_SIZE` switches body inspection on, up
-  to that size. It takes at most `64K`, since `waf` gets no more of a body than
-  that (see "The answer"). Form data and multipart bodies are read up to the
-  size. JSON and XML bodies are read only when no larger than the size, since
-  those cannot be read in part. Any other body is not read: the Core Rule Set
-  would read it as form data, where binary content such as a git push trips
+  to that size. It takes at most `8K`, so that `waf` answers in time (see
+  "Answering in time"). Form data and multipart bodies are read up to the size.
+  JSON and XML bodies are read only when no larger than the size, since those
+  cannot be read in part. A JSON body over 1 KiB is not read either, whatever
+  the size (see "Answering in time"). Any other body is not read: the Core Rule
+  Set would read it as form data, where binary content such as a git push trips
   rules written for text. A body the Core Rule Set cannot parse adds 5 to the
   score, and so does a multipart body cut by the limit in the middle of a part's
   header. Body inspection suits apps whose forms carry no code.
@@ -1952,20 +1945,19 @@ leave out a cookie only when its name matches exactly, case included.
 ### Ban lengths, response and scope
 
 `SWW_WAF_BAN_RESPONSE` is `403` by default, which makes a ban easy to recognise
-when debugging; `429` and `close` are the alternatives. Behind traefik, `close`
-does not leave the client unanswered: traefik answers `502`, as it does whenever
-its backend drops a connection. `SWW_WAF_BAN_SCOPE_V4_PREFIX` widens an IPv4 ban
-to the surrounding netblock. The four ban lengths are under "Bans".
+when debugging; `429` and `close` are the alternatives. `close` does not leave
+the client unanswered: the TLS-terminating proxy answers `502`, as it does
+whenever its backend drops a connection. `SWW_WAF_BAN_SCOPE_V4_PREFIX` widens an
+IPv4 ban to the surrounding netblock. The four ban lengths are under "Bans".
 
 ### Reputation
 
 No source is on by default. A source acts on a list kept elsewhere; the defaults
-judge a client only by what it does here. AbuseIPDB and CrowdSec also need an
-account or an engine of the operator's own. The list best suited to be on by
-default, Spamhaus DROP, has terms, below, that forbid frequent fetching, and
-Spamhaus may block an address that breaks them. Each `waf` fetches its own copy,
-so several of them on one host, sharing one address, would often fetch too close
-together.
+judge a client only by what it does here. AbuseIPDB also needs an account of the
+operator's own. The list best suited to be on by default, Spamhaus DROP, has
+terms, below, that forbid frequent fetching, and Spamhaus may block an address
+that breaks them. Each `waf` fetches its own copy, so several of them on one
+host, sharing one address, would often fetch too close together.
 
 - Blocklists (`SWW_WAF_BLOCKLIST_URLS`) are text files of addresses and
   netblocks, one to a line, as the Spamhaus DROP list is written. Anything after
@@ -1998,18 +1990,6 @@ together.
   percentage of every request and byte limit, and suits a list of addresses
   shared with ordinary visitors, such as Tor exits. `log` only notes the hit in
   the log line and raises an alert.
-- A CrowdSec engine on the host (`SWW_WAF_CROWDSEC_LAPI_URL`) has its decision
-  list fetched every minute, with `SWW_WAF_CROWDSEC_LAPI_KEY` in the `X-Api-Key`
-  header. The list is kept like a fetched blocklist, and a client on it is
-  banned (see "Bans"). Only decisions of the type `ban` on an address or a
-  netblock are used; any other, such as a captcha or a country, is left out. A
-  decision lasts for the `duration` it had left when the engine answered. This
-  is how a fleet-wide blocklist can arrive without `waf` depending on CrowdSec.
-  A fetch fails when:
-    - the engine answers other than `200`, a redirect included;
-    - the fetch does not finish within a minute;
-    - the answer is longer than 16 MiB;
-    - the answer is not a list of decisions.
 - Each DNS blocklist (`SWW_WAF_DNSBL_ZONES`) is asked about a client's own
   address in the background, the first time the client is seen. No request waits
   for the answer. The name asked about is the one RFC 5782 gives: the numbers of
@@ -2395,15 +2375,15 @@ runs no check, writes no request log line and counts nothing in the metrics.
 answer but the last below carries `X-Sww-Disposition`.
 
 - `X-Sww-Disposition: allow`, status `200`, no body. `rproxy` passes the request
-  to the app. With `SWW_WAF_ADD_LOOKUP_HEADERS` the answer also carries
-  `X-Client-ASN` and `X-Client-Country`, which `rproxy` adds to the request it
-  passes on. A header whose value is unknown is left out.
+  to the app. While `SWW_WAF_ADD_LOOKUP_HEADERS` is `true`, the answer also
+  carries `X-Client-ASN` and `X-Client-Country`, which `rproxy` adds to the
+  request it passes on. A header whose value is unknown is left out.
 - `X-Sww-Disposition: deny`, with the status, headers and body the visitor is to
   get. `rproxy` gives them to the visitor, less this header. The status is one
   of:
     - `SWW_WAF_BAN_RESPONSE`, for a refusal;
     - `403`, for a `block` rule or the Core Rule Set;
-    - `431`, for a request over the header limits;
+    - `414` or `431`, for a request over the header limits;
     - `404`, for a path under `/_sww/` that passes the checks, so that the app
       never sees that prefix.
 - `X-Sww-Disposition: close`, status `200`, no body. This takes the place of a
@@ -2418,9 +2398,7 @@ In `observe` mode a request that `enforce` mode would refuse is answered
 answered `404`.
 
 The Core Rule Set inspects the body a question carries only while
-`SWW_WAF_CORE_RULE_SET_BODY_INSPECTION_SIZE` is set. It inspects at most 64 KiB
-less one byte. So it does not inspect a JSON or XML body of 64 KiB or more,
-which may have been cut short.
+`SWW_WAF_CORE_RULE_SET_BODY_INSPECTION_SIZE` is set, and at most 8 KiB of it.
 
 ### Answering in time
 
@@ -2437,14 +2415,13 @@ client without an answer by then counts as unknown. No question waits on these,
 which run in the background:
 
 - the DNS blocklists and AbuseIPDB;
-- fetching the blocklists, the tag lists, the CrowdSec decision list and the
-  file `SWW_WAF_ASN_LIMIT_PERCENT_URL` names.
+- fetching the blocklists, the tag lists and the file
+  `SWW_WAF_ASN_LIMIT_PERCENT_URL` names.
 
 In `enforce` mode, a question does not wait for GeoJS when it is a request:
 
 - from a client on a fetched blocklist, while `SWW_WAF_BLOCKLIST_ACTION` is
   `deny`;
-- from a client on the CrowdSec decision list;
 - that would take its client over a rate limit at 100% of it, since a percentage
   can only lower a limit.
 
@@ -2465,33 +2442,57 @@ never wait. These can still wait for GeoJS:
 - a rule file;
 - the Core Rule Set.
 
-The header limits are fixed, with no setting. `waf` refuses a request over
-either one:
+The header limits are fixed, with no setting. A line's length is in bytes and
+does not count its line ending. `waf` refuses a request whose request line is
+longer than 8 KiB with `414`. An example is `GET /search?q=` followed by 30,000
+characters.
 
+It refuses a request with `431` for any of:
+
+- a header line longer than 8 KiB. Each value of a header sent twice is a line
+  of its own. `Host` counts as a line.
 - more than 50 cookies. Each part of its `Cookie` headers between semicolons
   counts as one, unless it is empty or only spaces and tabs.
 - more than 100 header fields. A header sent twice counts twice. `Host` and
   `Transfer-Encoding` do not count. `X-Request-ID` and `X-Forwarded-Proto` do.
 
-Real clients never reach these limits. The answer is `deny` with `431`, and the
-log line's action is `request_header_too_large`. The refusal makes no ban and is
-no offence.
+Real clients rarely reach these limits. nginx refuses lines over 8 KiB by
+default, and Apache's default limit is about the same. The answer is `deny`. The
+log line's action is `request_line_too_long` for `414` and
+`request_header_too_large` for `431`. The refusal makes no ban and is no
+offence.
 
 The header limits are the first check after `SWW_WAF_ALLOW_NETS`. A request over
 them is refused before any later check runs. So it causes no lookup, no query to
 an outside source and no rule match, and the rate limits do not count it. A
-client under a ban or in `SWW_WAF_DENY_NETS` also gets `431` for such a request.
+client under a ban or in `SWW_WAF_DENY_NETS` also gets `414` or `431` for such a
+request.
 
 The limits apply on every path and in every `SWW_WAF_CORE_RULE_SET_MODE`. A
 client in `SWW_WAF_ALLOW_NETS` skips them, as it skips the Core Rule Set. In
 `observe` mode such a request is answered `allow` with `would_action`, and no
 other check runs on it.
 
-The Core Rule Set runs each of its rules on each cookie, so thousands of small
-cookies would keep it busy for over a second. Within the limits, one long cookie
-or query string can still keep it busy for a fraction of a second. So enough
-such requests at once can overload `waf` past
-`SWW_RPROXY_WAF_BACKEND_TIMEOUT_MS`.
+The Core Rule Set is the one check a visitor can keep busy for long. It runs
+each of its rules on each part of a request, so thousands of small cookies would
+keep it busy for over a second. These fixed limits bound what it reads:
+
+- the header limits above;
+- `rproxy`'s limit of 32 KiB on the request line and headers together (see
+  "`rproxy`'s limits");
+- 8 KiB of a body, the most `SWW_WAF_CORE_RULE_SET_BODY_INSPECTION_SIZE` takes,
+  or 1 KiB of a JSON body.
+
+Coraza names each value in a JSON body by the whole path to it, such as
+`json.users.0.name`. So the names and values the Core Rule Set reads in a JSON
+body can add up to more than the body. From 1 KiB of JSON, Coraza makes at most
+8 KiB of them, no more than the largest body of another kind.
+
+A request can reach all of these at once. At paranoia level 4, with no rule
+switched off, the Core Rule Set takes under a second on one core of a current
+server to inspect it. So `waf` answers it within the default 2 seconds, even
+after the default 800 milliseconds of waiting for GeoJS. Enough such requests at
+once can still overload `waf` past `SWW_RPROXY_WAF_BACKEND_TIMEOUT_MS`.
 
 ### The report
 
@@ -2595,11 +2596,11 @@ request and ban notes name the site by its host.
 ## `rproxy`
 
 `sww rproxy` is the reverse proxy in front of one app. It asks `waf` about each
-request, and passes on what `waf` allows. It keeps nothing between requests and
-writes nothing to disk. When `waf` cannot be connected to, does not answer at
-all, or does not answer within `SWW_RPROXY_WAF_BACKEND_TIMEOUT_MS`,
-`SWW_RPROXY_WAF_BACKEND_NO_ANSWER_DISPOSITION` decides. Its default, `allow`,
-keeps the site answering.
+request, and passes on what `waf` allows. It writes nothing to disk. The only
+thing it keeps between requests is its circuit breaker for asks to `waf`.
+`SWW_RPROXY_WAF_BACKEND_NO_ANSWER_DISPOSITION` decides what is done with a
+request when `waf` gives no answer in time, and while the circuit breaker is
+open. Its default, `allow`, keeps the site answering.
 
 `rproxy` reads only its `SWW_RPROXY_` settings, which `docs/settings.md` lists.
 One of them is required: `SWW_RPROXY_WAF_BACKEND`, `waf`'s URL. It has no
@@ -2617,7 +2618,8 @@ only. The image runs it by default (see "Deployment").
 4. It refuses a request with a method it does not pass on, or one it cannot put
    to `waf` as the visitor sent it (see "Requests `rproxy` refuses itself").
 5. It reads up to the first 64 KiB of the body into memory.
-6. It sends `waf` the question (see "The question"). It speaks HTTP/1.1 to
+6. It sends `waf` the question (see "The question"), unless the circuit breaker
+   keeps it from asking (see "The circuit breaker"). It speaks HTTP/1.1 to
    `waf`, whatever `waf` offers. Go's HTTP/2 client would refuse to send a
    visitor's `Upgrade` header, and most `Connection` headers. The question never
    carries the visitor's `Trailer`.
@@ -2691,23 +2693,24 @@ log line has status `0`.
 ### Without an answer from `waf`
 
 `SWW_RPROXY_WAF_BACKEND_NO_ANSWER_DISPOSITION` decides what is done with the
-request only when `waf`:
+request when `waf`:
 
 - cannot be connected to;
 - does not answer at all;
 - does not answer within `SWW_RPROXY_WAF_BACKEND_TIMEOUT_MS`, which covers
   connecting, sending the question and reading the whole answer.
 
-An answer whose body breaks off counts as no answer at all.
+An answer whose body breaks off counts as no answer at all. The setting also
+decides, without asking `waf`, while the circuit breaker is open.
 
 `allow`, the default, passes the request to the app. `deny` answers `503`.
 Either way `rproxy` writes a process warning, its log line has
 `waf_backend_no_answer`, and it sends no report.
 
-A visitor can make `waf` slow. A request that keeps `waf` busy past
-`SWW_RPROXY_WAF_BACKEND_TIMEOUT_MS`, like any request while `waf` is overloaded,
-gets `SWW_RPROXY_WAF_BACKEND_NO_ANSWER_DISPOSITION`. With `deny`, such a request
-gets `503` instead of reaching the app.
+`waf` taking longer than `SWW_RPROXY_WAF_BACKEND_TIMEOUT_MS` to decide a request
+is a bug in `waf`. Such a request gets
+`SWW_RPROXY_WAF_BACKEND_NO_ANSWER_DISPOSITION`, like any request while `waf` is
+overloaded. With `deny`, it gets `503` instead of reaching the app.
 
 A path under `/_sww/` that `allow` would pass on is answered `404` instead, so
 that the app never sees that prefix.
@@ -2722,6 +2725,28 @@ A visitor that goes away while `waf` is being asked is no failure of `waf`.
 `SWW_RPROXY_WAF_BACKEND_NO_ANSWER_DISPOSITION` does not apply. Its log line has
 status `0` and no `disposition`.
 
+### The circuit breaker
+
+`rproxy` stops asking `waf` for a while when `waf` keeps failing to answer. An
+ask fails when `waf` gives no answer in time (see "Without an answer from
+`waf`"), or an answer `rproxy` cannot pass on. Any other answer in time
+succeeds, whatever it decides. A visitor that goes away while `waf` is being
+asked counts as neither.
+
+The breaker works like this:
+
+- It opens when 5 asks fail within 5 seconds. Fewer failures never open it.
+- While it is open, a request gets
+  `SWW_RPROXY_WAF_BACKEND_NO_ANSWER_DISPOSITION` at once, without asking `waf`.
+  It gets the same process warning and `waf_backend_no_answer` as a request
+  whose ask failed.
+- While it is open, one request a second still asks `waf`.
+- Each ask that succeeds clears the failures counted so far, and closes the
+  breaker if it is open.
+
+The breaker lives in memory, and a restart of `rproxy` closes it. It has no
+settings.
+
 ### Passing a request to the app
 
 `rproxy` sends the app at `SWW_RPROXY_UPSTREAM_URL` the visitor's request: the
@@ -2784,9 +2809,9 @@ its whole body. The visitor gets that answer at once, and the connection closes
 after it.
 
 The largest request line and headers is 32 KiB. A kept-open connection is closed
-after 120 seconds idle. Neither has a setting. traefik, by default, closes an
-unused connection after 90 seconds. So traefik closes first, and never sends a
-request on a connection `rproxy` is closing.
+after 120 seconds idle. Neither has a setting. The TLS-terminating proxy should
+close an unused connection sooner, so that it never sends a request on a
+connection `rproxy` is closing. traefik closes one after 90 seconds by default.
 
 What the visitor gets when a limit is passed:
 
@@ -2837,14 +2862,16 @@ chooses: `waf` runs `waf`, and with it unset the image runs `rproxy`.
 The usual setup is three containers on one private network:
 
 - the app;
-- `rproxy`, which traefik routes to, with `SWW_RPROXY_UPSTREAM_URL` naming the
-  app and `SWW_RPROXY_WAF_BACKEND` naming `waf`;
+- `rproxy`, which the TLS-terminating proxy forwards to, with
+  `SWW_RPROXY_UPSTREAM_URL` naming the app and `SWW_RPROXY_WAF_BACKEND` naming
+  `waf`;
 - `waf`, with `SWW_COMMAND=waf` and a volume for its state files.
 
 Each further app adds its own container and its own `rproxy`, whose
 `SWW_RPROXY_WAF_BACKEND` names the same `waf` (see "Sites"). Anything on that
 network can reach an app around `rproxy`, and can ask `waf` questions or send it
-reports. So the network holds only what you trust.
+reports. So the network holds only what you trust. `README.md` lists what the
+TLS-terminating proxy must do.
 
 ### `rproxy` in the app's container
 
@@ -2916,10 +2943,10 @@ process that stops at start is started again every second, not in a tight loop.
   container's output, which `docker logs` shows.
 - When a service exits, runit runs its `run` script again, and the container
   does not stop. Beside an app, the other process keeps running.
-- While `rproxy` is down, traefik answers `502`. While the app is down, `rproxy`
-  answers `502`, which is not a client offence. While `waf` is down,
-  `SWW_RPROXY_WAF_BACKEND_NO_ANSWER_DISPOSITION` decides (see "Without an answer
-  from `waf`").
+- While `rproxy` is down, the TLS-terminating proxy answers `502`. While the app
+  is down, `rproxy` answers `502`, which is not a client offence. While `waf` is
+  down, `SWW_RPROXY_WAF_BACKEND_NO_ANSWER_DISPOSITION` decides (see "Without an
+  answer from `waf`").
 - Only faults found at start stop `waf`:
     - invalid configuration;
     - a lookup database that is missing or unreadable;
@@ -2952,23 +2979,26 @@ checks:
 - With `SWW_COMMAND` unset, empty or `rproxy`, it passes while `rproxy` answers
   that request on `127.0.0.1`, at the port in `SWW_RPROXY_LISTEN_ADDR`, and the
   app accepts connections at `SWW_RPROXY_UPSTREAM_URL`. It does not ask `waf`,
-  so that the site stays in traefik's routes while `waf` is down.
+  so that the site stays in the TLS-terminating proxy's routes while `waf` is
+  down.
 - With any other value, it fails with a message naming `SWW_COMMAND` and its
   value.
 
-traefik sends a container no requests until it shows as healthy. So the check
-runs every second from the container's start until it first passes, for up to a
-minute, and every 30 seconds after that. An app with a health check of its own
-can replace the image's `HEALTHCHECK` with one that checks both.
+A TLS-terminating proxy that reads Docker's health status, as traefik does,
+sends a container no requests until it shows as healthy. So the check runs every
+second from the container's start until it first passes, for up to a minute, and
+every 30 seconds after that. An app with a health check of its own can replace
+the image's `HEALTHCHECK` with one that checks both.
 
 ### Ports
 
 `rproxy` listens on no port but the one in `SWW_RPROXY_LISTEN_ADDR`, 8080 by
-default, which traefik routes to. It passes requests to the app at
-`SWW_RPROXY_UPSTREAM_URL`, `http://127.0.0.1:8081` by default. Another port may
-be set: the health check follows the setting, and traefik's port label
-(`traefik.http.services.<name>.loadbalancer.server.port`) must name it. An app
-beside `rproxy` must leave that port free.
+default, which the TLS-terminating proxy forwards to. It passes requests to the
+app at `SWW_RPROXY_UPSTREAM_URL`, `http://127.0.0.1:8081` by default. Another
+port may be set: the health check follows the setting, and the TLS-terminating
+proxy must name it, as traefik's port label
+(`traefik.http.services.<name>.loadbalancer.server.port`) does. An app beside
+`rproxy` must leave that port free.
 
 `waf` listens on no port but the one in `SWW_WAF_LISTEN_ADDR`, 8080 by default.
 The questions, the reports and its own endpoints all come there.
@@ -2990,8 +3020,8 @@ host directory, keeps them across deploys. A host directory mounted there needs
 no change of owner, and files an earlier owner left in it can be read and
 replaced. The volume holds a few tens of MiB at most with the defaults, and
 needs no backup beyond the host's own. The image declares no volume, since every
-app image built on it would inherit it. `rproxy` keeps nothing, and needs no
-volume.
+app image built on it would inherit it. `rproxy` writes nothing to disk, and
+needs no volume.
 
 `waf` keeps its cache files in `SWW_WAF_CACHE_DIR`, `/var/cache/sww` by default,
 which the `run` script makes. The cache directory needs no volume and can be
@@ -3009,9 +3039,9 @@ in `docs/settings.md` shows the commands.
 ### Forwarded headers
 
 The app's TCP peer is `rproxy`, and the `X-Forwarded-For` the app receives ends
-with traefik's address, which `rproxy` adds after the visitor's. So the app must
-trust `rproxy`'s address for forwarded headers, besides the private address
-ranges traefik is on.
+with the TLS-terminating proxy's address, which `rproxy` adds after the
+visitor's. So the app must trust `rproxy`'s address for forwarded headers,
+besides the private address ranges the TLS-terminating proxy is on.
 
 - In a container of its own, `rproxy`'s address is on the private network. The
   usual default for a trusted-proxy setting, the private ranges, covers it.

docs/alerts.md

@@ -13,9 +13,8 @@ back or dropped.
   threshold. The request was refused unless the alert's `detail` gives `mode`:
   `detect` or `observe`.
 - `anomaly`: a count over an anomaly threshold.
-- `reputation_hit`: a request from a client on a blocklist, the CrowdSec
-  decision list or a DNS blocklist, or with an AbuseIPDB score that is a hit.
-  One alert per source.
+- `reputation_hit`: a request from a client on a blocklist or a DNS blocklist,
+  or with an AbuseIPDB score that is a hit. One alert per source.
 - `source_failure`: one of:
     - GeoJS failing;
     - a list that cannot be fetched;
@@ -69,8 +68,7 @@ on one line:
             "earlier_bans": {
                 "limit": 0,
                 "attack": 0,
-                "admin": 0,
-                "crowdsec": 0
+                "admin": 0
             }
         }
     },

docs/request-log.md

@@ -68,7 +68,8 @@ Every one of these lines has:
 ### 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.
+- `peer_ip`: the address of `rproxy`'s TCP peer, normally the TLS-terminating
+  proxy.
 - `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.
@@ -97,12 +98,13 @@ Every one of these lines has:
     - `client_denied`: refused for `SWW_WAF_DENY_NETS`, for a reputation source
       with the action `deny`, or for a tag in `SWW_WAF_TAG_DENY`;
     - `temporarily_banned`: refused under a ban that runs out, or for a `ban`
-      rule, a trap path or a CrowdSec decision that made such a ban;
+      rule or a trap path that made such a ban;
     - `permanently_banned`: refused under a ban that never runs out, including a
       ban this request made or made permanent;
     - `country_denied`, `client_is_rate_limited`, `blocked_by_block_rule` and
       `blocked_by_core_rule_set`: refused by that check;
-    - `request_header_too_large`: over a header limit;
+    - `request_line_too_long`: a request line over the header limits;
+    - `request_header_too_large`: headers over the header limits;
     - `own_endpoint`: answered at one of `waf`'s own endpoints, or `404` for a
       path under `/_sww/`.
 - `would_action`: in `observe` mode, what `enforce` mode would have done with a
@@ -118,15 +120,16 @@ Every one of these lines has:
     - `countries`: `country`, and `setting`, the country list that refused it;
     - `tag_deny`: `tag`, the tag of `SWW_WAF_TAG_DENY` the request carries;
     - `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`, `SWW_WAF_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`;
+    - `header_limits`: for a request line, `request_line_bytes` and
+      `request_line_bytes_limit`; for headers, `longest_header_line_bytes`,
+      `header_line_bytes_limit`, `fields`, `fields_limit`, `cookies` and
+      `cookies_limit`;
     - `core_rule_set`: `score`, and `threshold`,
       `SWW_WAF_CORE_RULE_SET_SCORE_THRESHOLD`;
     - `refusal_limit`: `window`, `count` and `limit`, of the refusal limit;
@@ -171,7 +174,6 @@ Every one of these lines has:
   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`.
 - `tags`: the request's tags, sorted, left out when it has none. Each tag and
@@ -236,7 +238,8 @@ meanings where they differ:
 - `disposition`: what was done with the request: `allow`, `deny` or `close`. It
   is `waf`'s answer, or the value of
   `SWW_RPROXY_WAF_BACKEND_NO_ANSWER_DISPOSITION`. It is left out when:
-    - `waf` was not asked, as for the health check;
+    - `waf` was not asked and `SWW_RPROXY_WAF_BACKEND_NO_ANSWER_DISPOSITION` did
+      not apply, as for the health check;
     - the visitor went away while `waf` was being asked;
     - `waf`'s answer had no valid `X-Sww-Disposition`;
     - `rproxy` could not pass on `waf`'s answer, and answered `502`.

docs/settings.md

@@ -150,7 +150,7 @@ cut off; the client is banned.
 - `SWW_WAF_LOOKUP_SOURCE` (default `geojs`): `geojs`, `file` or `off`. `off`
   stops the start while a setting that needs a lookup is set:
     - `SWW_WAF_EXCLUSIVELY_ALLOWED_COUNTRIES`;
-    - `SWW_WAF_ADD_LOOKUP_HEADERS`;
+    - `SWW_WAF_ADD_LOOKUP_HEADERS` set to `true`;
     - `SWW_WAF_TAG_DENY` or `SWW_WAF_TAG_LIMIT_PERCENT` naming a `country=` tag,
       or an `asn=` tag while `SWW_WAF_ROUTEWATCH_URL` is unset;
     - the two byte percentage lists and `SWW_WAF_ASN_LIMIT_PERCENT_URL`;
@@ -161,9 +161,11 @@ cut off; the client is banned.
 - `SWW_WAF_ASN_AND_COUNTRY_LOOKUP_TIMEOUT_MS` (default `800`): how long a
   request waits for its client's first answer from GeoJS, and how long a request
   to GeoJS may take. A time in milliseconds; never `off`.
-- `SWW_WAF_ADD_LOOKUP_HEADERS` (default `false`): `true` has `rproxy` pass the
+- `SWW_WAF_ADD_LOOKUP_HEADERS` (default `true`): `true` has `rproxy` pass the
   app the client's AS number in `X-Client-ASN` and its country in
-  `X-Client-Country`.
+  `X-Client-Country`. The default is `false` while `SWW_WAF_LOOKUP_SOURCE` is
+  `off`. With GeoJS, a new client's first request waits for its answer, up to
+  `SWW_WAF_ASN_AND_COUNTRY_LOOKUP_TIMEOUT_MS`.
 
 ## Country list
 
@@ -180,8 +182,8 @@ in [`SPEC.md`](../SPEC.md).
   `name=URL` pairs, such as `torexit=https://example.com/tor.txt`. A name is the
   tag, and may hold `=`, such as `vpn=mullvad`. Each list is an `http` or
   `https` URL fetched like a blocklist. A name or URL listed twice is refused.
-  So is a URL that is also in `SWW_WAF_BLOCKLIST_URLS`,
-  `SWW_WAF_ASN_LIMIT_PERCENT_URL`, or the CrowdSec decision list.
+  So is a URL that is also in `SWW_WAF_BLOCKLIST_URLS` or is
+  `SWW_WAF_ASN_LIMIT_PERCENT_URL`.
 - `SWW_WAF_TAG_DENY` (default empty): tags whose requests are refused, such as
   `torexit,country=CN`. A tag listed twice, an `asn=` tag without a number, or a
   `country=` tag without a country, is refused.
@@ -214,9 +216,6 @@ tag that no request can get stops the start. A request can get only these:
   `SWW_WAF_CORE_RULE_SET_MODE` nor `SWW_WAF_CORE_RULE_SET_SCORE_THRESHOLD` is
   `off`.
 
-`crowdsec` stops the start in both settings, because a CrowdSec decision refuses
-the request first.
-
 ## Biased thresholds
 
 - `SWW_WAF_ASN_BYTES_LIMIT_PERCENT` and `SWW_WAF_COUNTRY_BYTES_LIMIT_PERCENT`
@@ -252,10 +251,9 @@ the request first.
 - `SWW_WAF_CORE_RULE_SET_EXEMPT_PATHS` (default empty): path prefixes the Core
   Rule Set does not inspect.
 - `SWW_WAF_CORE_RULE_SET_BODY_INSPECTION_SIZE` (default `off`): `off`, or how
-  much of a request body 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)).
+  much of a request body the Core Rule Set reads, a size of at most `8K`. A
+  larger size would let one request keep it busy past `rproxy`'s timeout (see
+  "Answering in time" in [`SPEC.md`](../SPEC.md)).
 - `SWW_WAF_CORE_RULE_SET_EXCLUSIONS_FILE` (default unset): a file of Core Rule
   Set exclusions, written as Coraza directives. It is loaded before the Core
   Rule Set's rules, so it holds only `SecAction` and `SecRule` lines that
@@ -333,14 +331,6 @@ the request first.
   score, from 0 to 100, that is a hit.
 - `SWW_WAF_ABUSEIPDB_DAILY_BUDGET` (default `900`): the most checks made in a
   day, a whole number above zero. AbuseIPDB's free accounts may make 1,000.
-- `SWW_WAF_CROWDSEC_LAPI_URL` (default unset): the local API of a CrowdSec
-  engine you run, such as `http://172.17.0.1:8080`. An `http` or `https` URL
-  without a user or a fragment; its decision list is at `v1/decisions` under it.
-  Set without the key, it is refused. So is a decision list URL that is also in
-  `SWW_WAF_BLOCKLIST_URLS`, or that is `SWW_WAF_ASN_LIMIT_PERCENT_URL`.
-- `SWW_WAF_CROWDSEC_LAPI_KEY` (default unset): the key the engine gave for
-  `smallwebwaf`, as `cscli bouncers add smallwebwaf` prints it. Set without the
-  URL, it is refused.
 - `SWW_WAF_DNSBL_ABUSEIPDB_ACTION` (default `limit:25`): `deny`,
   `limit:<percent>` or `log`, for DNS blocklist and AbuseIPDB hits.
 - `SWW_WAF_IP_REPUTATION_CACHE_TTL` (default `24h`): how long a zone's verdict
@@ -432,8 +422,9 @@ A few limits are fixed rather than settings:
 - at most 20,000 anomaly counters are kept;
 - each alert destination's queue holds at most 1,000 alerts;
 - `waf` holds at most 10,000 answered requests awaiting their reports;
-- `waf` refuses a request with more than 50 cookies or more than 100 header
-  fields (see "Answering in time" under "`waf`" in [`SPEC.md`](../SPEC.md));
+- `waf` refuses a request with a request line or header line over 8 KiB, more
+  than 50 cookies or more than 100 header fields (see "Answering in time" under
+  "`waf`" in [`SPEC.md`](../SPEC.md));
 - `rproxy` takes a request line and headers of at most 32 KiB, and closes a
   kept-open connection idle for 120 seconds;
 - `rproxy` reads at most 1 MiB of the body of `waf`'s answer, and answers `502`
@@ -461,10 +452,9 @@ start, and an invalid value stops the start. Any can be given as a file, as a
   for `waf`'s answer, to a question and to a report. A time in milliseconds;
   never `off`.
 - `SWW_RPROXY_WAF_BACKEND_NO_ANSWER_DISPOSITION` (default `allow`): what is done
-  with a request when `waf` cannot be connected to, does not answer at all, or
-  does not answer within `SWW_RPROXY_WAF_BACKEND_TIMEOUT_MS`. `allow` passes it
-  to the app, and `deny` answers `503`. It does not apply to an answer `waf`
-  gives, such as an error.
+  with a request when `waf` gives no answer in time, and while the circuit
+  breaker for asks to `waf` is open. `allow` passes it to the app, and `deny`
+  answers `503`. It does not apply to an answer `waf` gives, such as an error.
 - `SWW_RPROXY_MAX_REQUEST_SIZE` (default `100M`): the largest request body. A
   size or `off`.
 - `SWW_RPROXY_MAX_RESPONSE_SIZE` (default `1G`): the largest response body. A
@@ -486,9 +476,9 @@ start, and an invalid value stops the start. Any can be given as a file, as a
   `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. 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.
+  reach `rproxy` directly, or visitors on a private network reach the
+  TLS-terminating proxy, they can name another address in the header. Narrowing
+  the setting to the TLS-terminating proxy's own network closes that gap.
 
 ## The image's command
 

docs/state-files.md

@@ -25,7 +25,7 @@ Active and past bans: every ban an admin made, and up to `SWW_WAF_MAX_BANS` of
 those `waf` made. Per entry:
 
 - `netblock`, `start` and `expires` (`null` for a permanent ban);
-- `cause`: `attack`, `limit`, `admin` or `crowdsec`;
+- `cause`: `attack`, `limit` or `admin`;
 - `reason`: a short reason;
 - `lifted`: when an admin lifted it, if one did;
 - `notes`: the notes below.

internal/alerts/alerts.go

@@ -48,9 +48,8 @@ const (
 	// SWW_WAF_CORE_RULE_SET_SCORE_THRESHOLD, refused in block mode, let through in
 	// detect mode.
 	EventCoreRuleSetMatch = "core_rule_set_match"
-	// EventReputationHit is a request whose client a blocklist, the
-	// CrowdSec decision list or a DNSBL zone lists, or whose AbuseIPDB score
-	// is a hit.
+	// EventReputationHit is a request whose client a blocklist or a DNSBL
+	// zone lists, or whose AbuseIPDB score is a hit.
 	EventReputationHit = "reputation_hit"
 	// EventSourceFailure is GeoJS failing or refusing sww, a fetch
 	// of a list failing, a query to a DNSBL zone or a check with AbuseIPDB

internal/bans/bans.go

@@ -1,10 +1,8 @@
 // Package bans is the ban ledger: the bans sww makes on the
 // netblocks of clients that break a rate limit, a byte limit or the refusal
-// limit, show a clear sign of attack or are listed by the CrowdSec
-// decision list, and
-// those an admin makes, with their notes, as the "Bans" section of SPEC.md
-// describes. The bans are kept in memory, and written to bans.json and
-// read from it by the state package.
+// limit or show a clear sign of attack, and those an admin makes, with their
+// notes, as the "Bans" section of SPEC.md describes. The bans are kept in
+// memory, and written to bans.json and read from it by the state package.
 package bans
 
 import (
@@ -28,9 +26,6 @@ const (
 	// CauseAdmin is a ban an admin made, or one sww made that an
 	// admin keeps. It is never dropped.
 	CauseAdmin = "admin"
-	// CauseCrowdSec is a ban sww made for a client the CrowdSec
-	// decision list lists. It ends when CrowdSec's decision does.
-	CauseCrowdSec = "crowdsec"
 )
 
 // repeatFactor is how many times as long as the netblock's last ban a ban
@@ -45,8 +40,8 @@ type Params struct {
 	// LimitBanDuration is how long a first ban for a broken limit lasts.
 	LimitBanDuration time.Duration
 	// LimitBanRepeatWindow is how soon after the end of the netblock's
-	// ban that ended last, other than one for a clear sign of attack or for
-	// CrowdSec's decision, a broken limit counts as a repeat, which bans for
+	// ban that ended last, other than one for a clear sign of attack, a
+	// broken limit counts as a repeat, which bans for
 	// repeatFactor times as long as that ban.
 	LimitBanRepeatWindow time.Duration
 	// A ban for a broken limit that would be longer than
@@ -68,11 +63,10 @@ type Ban struct {
 	Start    time.Time
 	// Expires is when the ban ends, zero for a permanent ban.
 	Expires time.Time
-	// Cause is CauseLimit, CauseAttack, CauseAdmin or CauseCrowdSec.
+	// Cause is CauseLimit, CauseAttack or CauseAdmin.
 	Cause string
-	// Reason is a short text: for a ban sww made, the limit broken,
-	// the rule that matched or the scenario of CrowdSec's decision; for an
-	// admin's, what the admin wrote.
+	// Reason is a short text: for a ban sww made, the limit broken or
+	// the rule that matched; for an admin's, what the admin wrote.
 	Reason string
 	// Lifted is when an admin lifted the ban, zero while no admin has. A
 	// lifted ban refuses nothing, and does not make the netblock's next
@@ -133,8 +127,7 @@ type Notes struct {
 	// log's reputation names them. It is left out when none did.
 	Reputation []ReputationHit `json:"reputation,omitempty"`
 	// Request is the request that broke the limit, or whose bytes broke
-	// it, that was the clear sign of attack, or that came from a client the
-	// CrowdSec decision list lists.
+	// it, or that was the clear sign of attack.
 	Request Request `json:"request"`
 	// Requests is how many requests the netblock has sent since it was
 	// first seen, and Refused how many of them the ban has refused so
@@ -148,9 +141,8 @@ type Notes struct {
 
 // ReputationHit is a reputation source that listed a client, as a
 // reputation_hit alert's detail gives it: Source is the URL of the
-// blocklist or of the CrowdSec decision list, the DNSBL zone with its key
-// masked, or "abuseipdb", and Score, for AbuseIPDB alone, its score of the
-// client.
+// blocklist, the DNSBL zone with its key masked, or "abuseipdb", and Score,
+// for AbuseIPDB alone, its score of the client.
 type ReputationHit struct {
 	Source string `json:"source"`
 	Score  *int64 `json:"score,omitempty"`
@@ -158,10 +150,9 @@ type ReputationHit struct {
 
 // EarlierBans counts a netblock's bans before a ban, by cause.
 type EarlierBans struct {
-	Limit    int `json:"limit"`
-	Attack   int `json:"attack"`
-	Admin    int `json:"admin"`
-	CrowdSec int `json:"crowdsec"`
+	Limit  int `json:"limit"`
+	Attack int `json:"attack"`
+	Admin  int `json:"admin"`
 }
 
 // Request is a request in a ban's notes. Each text is cut to 256 bytes.
@@ -303,8 +294,7 @@ func activeBan(bans []Ban, now time.Time) *Ban {
 // BanForLimit bans netblock at now for a broken limit, with notes, and
 // returns the ban, and true. A first ban lasts LimitBanDuration. A ban
 // made within LimitBanRepeatWindow after the netblock's ban that ended
-// last, other than one for a clear sign of attack or for CrowdSec's
-// decision, or a lifted one, lasts
+// last, other than one for a clear sign of attack or a lifted one, lasts
 // repeatFactor times as long as that one. A ban that would be longer
 // than LimitBanPermanentAbove is permanent instead. If a ban on netblock is still
 // active, as when two of its requests break a limit at once, that ban is
@@ -318,7 +308,6 @@ func (l *Ledger) BanForLimit(
 	return l.ban(
 		netblock,
 		now,
-		time.Time{},
 		CauseLimit,
 		limitReason(notes),
 		notes,
@@ -334,7 +323,6 @@ func (l *Ledger) WouldBanForLimit(
 	return l.ban(
 		netblock,
 		now,
-		time.Time{},
 		CauseLimit,
 		limitReason(notes),
 		notes,
@@ -353,7 +341,6 @@ func (l *Ledger) BanForAttack(
 	return l.ban(
 		netblock,
 		now,
-		time.Time{},
 		CauseAttack,
 		attackReason(notes),
 		notes,
@@ -369,7 +356,6 @@ func (l *Ledger) WouldBanForAttack(
 	return l.ban(
 		netblock,
 		now,
-		time.Time{},
 		CauseAttack,
 		attackReason(notes),
 		notes,
@@ -377,51 +363,9 @@ func (l *Ledger) WouldBanForAttack(
 	)
 }
 
-// BanForCrowdSec bans netblock at now until expires, when CrowdSec's
-// decision on the client ends, with notes, and returns the ban, and
-// whether it made it, as BanForLimit does. Its reason is "CrowdSec's
-// decision for <scenario>", the scenario that made the decision.
-func (l *Ledger) BanForCrowdSec(
-	netblock netip.Prefix,
-	now, expires time.Time,
-	scenario string,
-	notes Notes,
-) (Ban, bool) {
-	return l.ban(
-		netblock,
-		now,
-		expires,
-		CauseCrowdSec,
-		crowdSecReason(scenario),
-		notes,
-		true,
-	)
-}
-
-// WouldBanForCrowdSec returns what BanForCrowdSec would, without making
-// the ban: what observe mode would have done.
-func (l *Ledger) WouldBanForCrowdSec(
-	netblock netip.Prefix,
-	now, expires time.Time,
-	scenario string,
-	notes Notes,
-) (Ban, bool) {
-	return l.ban(
-		netblock,
-		now,
-		expires,
-		CauseCrowdSec,
-		crowdSecReason(scenario),
-		notes,
-		false,
-	)
-}
-
-// WouldBePermanent reports whether a ban on netblock for cause, CauseLimit,
-// CauseAttack or CauseCrowdSec, made at now would be permanent, as
-// BanForLimit, BanForAttack or BanForCrowdSec would make it. It works out
-// nothing else of the ban. A ban for CrowdSec's decision is never
-// permanent: it ends with the decision.
+// WouldBePermanent reports whether a ban on netblock for cause, CauseLimit
+// or CauseAttack, made at now would be permanent, as BanForLimit or
+// BanForAttack would make it. It works out nothing else of the ban.
 func (l *Ledger) WouldBePermanent(
 	netblock netip.Prefix, now time.Time, cause string,
 ) bool {
@@ -433,14 +377,11 @@ func (l *Ledger) WouldBePermanent(
 		held = *bans
 	}
 
-	switch cause {
-	case CauseAttack:
+	if cause == CauseAttack {
 		return l.attackExpiry(held, now).IsZero()
-	case CauseLimit:
-		return l.limitExpiry(held, now).IsZero()
-	default: // CauseCrowdSec
-		return false
 	}
+
+	return l.limitExpiry(held, now).IsZero()
 }
 
 // limitReason is the reason of a ban for a broken limit, with notes.
@@ -459,12 +400,6 @@ func attackReason(notes Notes) string {
 	return "matched the rule " + notes.RuleID
 }
 
-// crowdSecReason is the reason of a ban for CrowdSec's decision, which
-// scenario made.
-func crowdSecReason(scenario string) string {
-	return "CrowdSec's decision for " + scenario
-}
-
 // BanForAdmin bans netblock at now for an admin, with reason, until
 // expires, or for good when expires is zero, and returns the ban, whose
 // cause is CauseAdmin. Unlike BanForLimit and BanForAttack, it makes the
@@ -704,15 +639,13 @@ func (l *Ledger) holds(netblock netip.Prefix, start time.Time) bool {
 	})
 }
 
-// ban bans netblock at now for cause, with reason and notes, as
-// BanForLimit, BanForAttack and BanForCrowdSec describe, and returns the
-// ban, and whether it made it. expires is when a ban for CauseCrowdSec
-// ends, and zero for the others, whose end the ledger works out. Unless
-// keep is true, the ban is not made, only returned: it is the ban that
-// would have been made.
+// ban bans netblock at now for cause, CauseLimit or CauseAttack, with
+// reason and notes, as BanForLimit and BanForAttack describe, and returns
+// the ban, and whether it made it. Unless keep is true, the ban is not
+// made, only returned: it is the ban that would have been made.
 func (l *Ledger) ban(
 	netblock netip.Prefix,
-	now, expires time.Time,
+	now time.Time,
 	cause, reason string,
 	notes Notes,
 	keep bool,
@@ -743,13 +676,10 @@ func (l *Ledger) ban(
 		Notes:    notes,
 	}
 
-	switch cause {
-	case CauseAttack:
+	if cause == CauseAttack {
 		ban.Expires = l.attackExpiry(held, now)
-	case CauseLimit:
+	} else {
 		ban.Expires = l.limitExpiry(held, now)
-	default: // CauseCrowdSec
-		ban.Expires = expires
 	}
 
 	if !keep {
@@ -784,16 +714,13 @@ func earlierBans(held []Ban) EarlierBans {
 			fromHere.Attack++
 		case CauseAdmin:
 			fromHere.Admin++
-		case CauseCrowdSec:
-			fromHere.CrowdSec++
 		}
 
 		notes := ban.Notes.EarlierBans
 		count := EarlierBans{
-			Limit:    notes.Limit + fromHere.Limit,
-			Attack:   notes.Attack + fromHere.Attack,
-			Admin:    notes.Admin + fromHere.Admin,
-			CrowdSec: notes.CrowdSec + fromHere.CrowdSec,
+			Limit:  notes.Limit + fromHere.Limit,
+			Attack: notes.Attack + fromHere.Attack,
+			Admin:  notes.Admin + fromHere.Admin,
 		}
 
 		// Of counts that name as many bans, the earlier ban's is taken: it
@@ -808,7 +735,7 @@ func earlierBans(held []Ban) EarlierBans {
 
 // total returns how many bans e counts, of all causes.
 func (e EarlierBans) total() int {
-	return e.Limit + e.Attack + e.Admin + e.CrowdSec
+	return e.Limit + e.Attack + e.Admin
 }
 
 // markChanged has Changed receive a value, unless one is waiting already.
@@ -913,9 +840,9 @@ func (l *Ledger) add(ban Ban) {
 // limitExpiry returns when a ban for a broken limit made at now ends, or
 // zero when it is permanent. held are the netblock's bans, none of them
 // active, of which the one that ended last, other than a ban for a clear
-// sign of attack or for CrowdSec's decision, or a lifted one, can make the
-// new ban longer. A ban an admin adds to bans.json can start after
-// another and end before it, so that one is looked for among them all.
+// sign of attack or a lifted one, can make the new ban longer. A ban an
+// admin adds to bans.json can start after another and end before it, so
+// that one is looked for among them all.
 func (l *Ledger) limitExpiry(held []Ban, now time.Time) time.Time {
 	length := l.params.LimitBanDuration
 

internal/bans/crowdsec_test.go

@@ -1,136 +0,0 @@
-package bans_test
-
-import (
-	"net/netip"
-	"reflect"
-	"testing"
-	"time"
-
-	"sneak.berlin/go/smallwebwaf/internal/bans"
-)
-
-// scenario is the scenario of the tests' CrowdSec decisions.
-const scenario = "crowdsecurity/ssh-bf"
-
-func TestCrowdSecBanLastsUntilTheDecisionEnds(t *testing.T) {
-	t.Parallel()
-
-	ledger := bans.New(defaultParams())
-	netblock := netip.MustParsePrefix("203.0.113.9/32")
-	expires := midnight().Add(4 * time.Hour)
-
-	// The ban that would be made is not made.
-	would, wouldBan := ledger.WouldBanForCrowdSec(
-		netblock,
-		midnight(),
-		expires,
-		scenario,
-		bans.Notes{},
-	)
-	if !wouldBan || len(ledger.Bans(netblock)) != 0 {
-		t.Errorf(
-			"would ban %t, and the ledger holds %+v, want true and nothing",
-			wouldBan,
-			ledger.Bans(netblock),
-		)
-	}
-
-	const reason = "CrowdSec's decision for " + scenario
-
-	ban, made := ledger.BanForCrowdSec(
-		netblock,
-		midnight(),
-		expires,
-		scenario,
-		bans.Notes{},
-	)
-	if !made || !reflect.DeepEqual(ban, would) ||
-		ban.Cause != bans.CauseCrowdSec ||
-		!ban.Expires.Equal(expires) ||
-		ban.Reason != reason ||
-		ledger.Made(bans.CauseCrowdSec) != 1 {
-		t.Errorf(
-			"made %t the ban %+v, want the one that would be made, %+v, for "+
-				"crowdsec until %s",
-			made,
-			ban,
-			would,
-			expires,
-		)
-	}
-
-	// A second decision on the netblock while the ban lasts makes no other.
-	again, made := ledger.BanForCrowdSec(netblock, midnight().Add(time.Hour),
-		expires.Add(time.Hour), scenario, bans.Notes{})
-	if made || !again.Expires.Equal(expires) ||
-		ledger.Made(bans.CauseCrowdSec) != 1 {
-		t.Errorf(
-			"made %t the ban %+v while the first lasts, want none",
-			made,
-			again,
-		)
-	}
-}
-
-func TestCrowdSecBanIsNeverMadePermanent(t *testing.T) {
-	t.Parallel()
-
-	ledger := bans.New(defaultParams())
-	netblock := netip.MustParsePrefix("203.0.113.9/32")
-	expires := midnight().Add(4 * time.Hour)
-	ledger.BanForCrowdSec(
-		netblock,
-		midnight(),
-		expires,
-		scenario,
-		bans.Notes{},
-	)
-
-	// A request as the ban ends is refused, and leaves it as it is.
-	last := expires.Add(-time.Nanosecond)
-
-	held, banned, madePermanent := ledger.Check(netblock.Addr(), last)
-	if !banned || madePermanent || !held.Expires.Equal(expires) ||
-		ledger.WouldBePermanent(netblock, last, bans.CauseCrowdSec) {
-		t.Errorf(
-			"as the ban ends, banned %t with %+v, made permanent %t, want "+
-				"refused under the ban as it was",
-			banned,
-			held,
-			madePermanent,
-		)
-	}
-
-	if _, banned, _ := ledger.Check(netblock.Addr(), expires); banned {
-		t.Error("the ban refuses a request once the decision has ended")
-	}
-}
-
-func TestCrowdSecBanIsCountedAndDoesNotLengthenTheNextBanForALimit(
-	t *testing.T,
-) {
-	t.Parallel()
-
-	ledger := bans.New(defaultParams())
-	netblock := netip.MustParsePrefix("203.0.113.9/32")
-
-	// Three times the three days would be permanent; a limit broken as the
-	// ban for CrowdSec's decision ends bans for an hour, as a first broken
-	// limit does.
-	crowdSec, _ := ledger.BanForCrowdSec(
-		netblock,
-		midnight(),
-		midnight().Add(3*day),
-		scenario,
-		bans.Notes{},
-	)
-	limit, _ := ledger.BanForLimit(netblock, crowdSec.Expires, bans.Notes{})
-
-	if limit.Expires.Sub(limit.Start) != time.Hour ||
-		limit.Notes.EarlierBans != (bans.EarlierBans{CrowdSec: 1}) {
-		t.Errorf(
-			"the ban for a limit is %+v, want one of an hour after one for crowdsec",
-			limit,
-		)
-	}
-}

internal/config/waf.go

@@ -84,7 +84,8 @@ type WAF struct {
 	// client's first answer from GeoJS while a setting needs it
 	// (SWW_WAF_ASN_AND_COUNTRY_LOOKUP_TIMEOUT_MS), which cannot be off.
 	// AddLookupHeaders is true when the app is passed the client's AS number
-	// and country in headers (SWW_WAF_ADD_LOOKUP_HEADERS).
+	// and country in headers (SWW_WAF_ADD_LOOKUP_HEADERS), by default unless
+	// LookupSource is off.
 	LookupSource               string
 	LookupDBPath               string
 	ASNAndCountryLookupTimeout time.Duration
@@ -157,13 +158,6 @@ type WAF struct {
 	DNSBLAbuseIPDBLimitPercent int64
 	IPReputationCacheTTL       time.Duration
 	DNSBLAbuseIPDBTimeout      time.Duration
-	// CrowdSecDecisionsURL is where the decision list of the CrowdSec
-	// engine whose local API SWW_WAF_CROWDSEC_LAPI_URL names is fetched from:
-	// that URL with v1/decisions added to its path, "" while it is unset and
-	// none is. CrowdSecKey is the key the engine is asked with
-	// (SWW_WAF_CROWDSEC_LAPI_KEY).
-	CrowdSecDecisionsURL string
-	CrowdSecKey          string
 	// BanResponse is the status a refused client is answered with, 403
 	// or 429, or 0 to close the connection without an answer
 	// (SWW_WAF_BAN_RESPONSE). It answers a banned client, a request that
@@ -371,8 +365,8 @@ var (
 		"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 waf gets of a body")
+	errOver8K       = errors.New(
+		"is more than 8K, the most the Core Rule Set can read in time")
 	errNotDurationAboveZero = errors.New(
 		"is not a duration above zero, such as 1h or 7d")
 	errNotNumberAboveZero = errors.New(
@@ -473,21 +467,12 @@ var (
 		"is not an IP address with an optional port, " +
 			"such as 192.0.2.53 or [2001:db8::53]:5353",
 	)
-	errNotLAPIURL = errors.New(
-		"is not an http or https URL without a user or a fragment, " +
-			"such as http://172.17.0.1:8080")
 	errNotRouteWatchURL = errors.New(
 		"is not an http or https URL without a user or a fragment, " +
 			"such as https://routewatch.example")
-	errNeedsLAPIKey  = errors.New("the engine answers no request without it")
-	errLAPIKeyUnused = errors.New(
-		"it is sent only to the engine at that URL",
-	)
-	errAnotherList = errors.New(
+	errFetchedOtherwise = errors.New(
 		"is in SWW_WAF_BLOCKLIST_URLS or is SWW_WAF_ASN_LIMIT_PERCENT_URL too",
 	)
-	errFetchedOtherwise = errors.New("is in SWW_WAF_BLOCKLIST_URLS, is " +
-		"SWW_WAF_ASN_LIMIT_PERCENT_URL or is the CrowdSec decision list too")
 	errNotTagList = errors.New(
 		"is not a name, = and an http or https URL, such as " +
 			"torexit=https://example.com/tor.txt")
@@ -502,8 +487,6 @@ var (
 	errExploitTag = errors.New(
 		"cannot lower limits: the rate limits count a request before its " +
 			"rules are matched")
-	errCrowdSecTag = errors.New(
-		"cannot be used: a CrowdSec decision refuses the request first")
 	errNoRequestGetsTag = errors.New(
 		"is a tag no request can get: it is not a name in SWW_WAF_TAG_LISTS, an " +
 			"asn= or country= tag, a dnsbl= tag of a zone in SWW_WAF_DNSBL_ZONES, " +
@@ -567,7 +550,6 @@ func WAFFromEnvironment(v *viper.Viper) (*WAF, error) {
 			"SWW_WAF_ASN_AND_COUNTRY_LOOKUP_TIMEOUT_MS",
 			"800",
 		),
-		AddLookupHeaders: env.boolean("SWW_WAF_ADD_LOOKUP_HEADERS", "false"),
 		ExclusivelyAllowedCountries: env.countries(
 			"SWW_WAF_EXCLUSIVELY_ALLOWED_COUNTRIES", ""),
 		TagLists:        env.tagLists("SWW_WAF_TAG_LISTS"),
@@ -605,10 +587,6 @@ func WAFFromEnvironment(v *viper.Viper) (*WAF, error) {
 			"SWW_WAF_DNSBL_ABUSEIPDB_TIMEOUT_MS",
 			"2000",
 		),
-		CrowdSecDecisionsURL: env.crowdSecDecisionsURL(
-			"SWW_WAF_CROWDSEC_LAPI_URL",
-		),
-		CrowdSecKey: env.secret("SWW_WAF_CROWDSEC_LAPI_KEY"),
 		BanResponse: env.banResponse("SWW_WAF_BAN_RESPONSE", "403"),
 		LimitBanDuration: env.durationNotOff(
 			"SWW_WAF_LIMIT_BAN_DURATION",
@@ -746,6 +724,9 @@ func WAFFromEnvironment(v *viper.Viper) (*WAF, error) {
 
 	cfg.LogRemoteAppName = env.appName("SWW_WAF_LOG_REMOTE_APP_NAME",
 		cfg.InstanceName, cfg.LogRemoteURL != nil)
+	// The app gets the headers by default, unless no client is looked up.
+	cfg.AddLookupHeaders = env.boolean("SWW_WAF_ADD_LOOKUP_HEADERS",
+		strconv.FormatBool(cfg.LookupSource != off))
 	cfg.BlocklistAction, cfg.BlocklistLimitPercent = env.action(
 		"SWW_WAF_BLOCKLIST_ACTION", "deny")
 	cfg.DNSBLAbuseIPDBAction, cfg.DNSBLAbuseIPDBLimitPercent = env.action(
@@ -755,7 +736,6 @@ func WAFFromEnvironment(v *viper.Viper) (*WAF, error) {
 	env.checkLookupDBPath(cfg)
 	env.checkCountriesAndLookups(cfg)
 	env.checkASNLimitPercentURL(cfg)
-	env.checkCrowdSec(cfg)
 	env.checkTagLists(cfg)
 	env.checkTags(cfg)
 
@@ -1061,26 +1041,6 @@ func (e *environment) resolver(name string) netip.AddrPort {
 	return resolver
 }
 
-// crowdSecDecisionsURL reads the setting that is the URL of the CrowdSec
-// engine's local API, such as http://172.17.0.1:8080, and returns the URL
-// its decision list is fetched from, that URL with v1/decisions added to
-// its path, "" while it is unset or empty.
-func (e *environment) crowdSecDecisionsURL(name string) string {
-	value := e.value(name, "")
-	if value == "" {
-		return ""
-	}
-
-	lapi, err := url.Parse(value)
-	if err != nil || !isHTTPURL(lapi) {
-		e.check(name, fmt.Errorf("%q %w", value, errNotLAPIURL))
-
-		return ""
-	}
-
-	return lapi.JoinPath("v1", "decisions").String()
-}
-
 // routeWatchURL reads the setting that is the URL of a routewatch instance,
 // "" while it is unset or empty.
 func (e *environment) routeWatchURL(name string) string {
@@ -1190,39 +1150,12 @@ func (e *environment) checkASNLimitPercentURL(cfg *WAF) {
 	}
 }
 
-// checkCrowdSec refuses SWW_WAF_CROWDSEC_LAPI_URL without
-// SWW_WAF_CROWDSEC_LAPI_KEY, the key without the URL, and a decision list
-// that is fetched as another list too.
-func (e *environment) checkCrowdSec(cfg *WAF) {
-	decisionsURL := cfg.CrowdSecDecisionsURL
-
-	switch {
-	case decisionsURL != "" && cfg.CrowdSecKey == "":
-		e.check("SWW_WAF_CROWDSEC_LAPI_URL", fmt.Errorf(
-			"is set while SWW_WAF_CROWDSEC_LAPI_KEY is unset; %w",
-			errNeedsLAPIKey,
-		))
-	case decisionsURL == "" && cfg.CrowdSecKey != "":
-		e.check("SWW_WAF_CROWDSEC_LAPI_KEY", fmt.Errorf(
-			"is set while SWW_WAF_CROWDSEC_LAPI_URL is unset; %w",
-			errLAPIKeyUnused,
-		))
-	case decisionsURL != "" && (slices.Contains(cfg.BlocklistURLs, decisionsURL) ||
-		decisionsURL == cfg.ASNLimitPercentURL):
-		e.check(
-			"SWW_WAF_CROWDSEC_LAPI_URL",
-			fmt.Errorf("gives the decision list %q, which %w",
-				decisionsURL, errAnotherList),
-		)
-	}
-}
-
 // checkTagLists refuses a list of SWW_WAF_TAG_LISTS whose URL is fetched as
 // another list too: the file at a URL is read as one kind of list.
 func (e *environment) checkTagLists(cfg *WAF) {
 	for _, list := range cfg.TagLists {
 		if slices.Contains(cfg.BlocklistURLs, list.URL) ||
-			list.URL == cfg.ASNLimitPercentURL || list.URL == cfg.CrowdSecDecisionsURL {
+			list.URL == cfg.ASNLimitPercentURL {
 			e.check(
 				"SWW_WAF_TAG_LISTS",
 				fmt.Errorf("%q %w", list.URL, errFetchedOtherwise),
@@ -1232,8 +1165,7 @@ func (e *environment) checkTagLists(cfg *WAF) {
 }
 
 // checkTags refuses a tag of SWW_WAF_TAG_DENY or SWW_WAF_TAG_LIMIT_PERCENT that would
-// never apply: crowdsec, whose request is refused before tags are acted on, and
-// any tag these settings cannot give a request.
+// never apply: any tag these settings cannot give a request.
 func (e *environment) checkTags(cfg *WAF) {
 	for _, tag := range cfg.TagDeny {
 		e.check("SWW_WAF_TAG_DENY", checkTag(cfg, tag))
@@ -1246,10 +1178,6 @@ func (e *environment) checkTags(cfg *WAF) {
 
 // checkTag returns an error when tag would never apply, as checkTags says.
 func checkTag(cfg *WAF, tag string) error {
-	if tag == CrowdSecTag {
-		return fmt.Errorf("%q %w", tag, errCrowdSecTag)
-	}
-
 	if !requestCanGetTag(cfg, tag) {
 		return fmt.Errorf("%q %w", MaskZoneKey(tag), errNoRequestGetsTag)
 	}
@@ -1673,16 +1601,16 @@ func durationOrDays(value string) (time.Duration, error) {
 }
 
 // parseCoreRuleSetBodyInspectionSize reads the most of a request body the Core Rule Set
-// reads: a size as parseSize reads it, or off, but at most 64K, since waf
-// gets no more of a body than that.
+// reads: a size as parseSize reads it, or off, but at most 8K, so that one
+// request cannot keep the Core Rule Set busy past rproxy's timeout.
 func parseCoreRuleSetBodyInspectionSize(value string) (int64, error) {
 	limit, err := parseSize(value)
 	if err != nil {
 		return 0, err
 	}
 
-	if limit > 64*kibibyte {
-		return 0, fmt.Errorf("%q %w", value, errOver64K)
+	if limit > 8*kibibyte {
+		return 0, fmt.Errorf("%q %w", value, errOver8K)
 	}
 
 	return limit, nil
@@ -2010,7 +1938,6 @@ const (
 	DNSBLTagPrefix   = "dnsbl="
 	PrefixTagPrefix  = "prefix="
 	AbuseIPDBTag     = "abuseipdb"
-	CrowdSecTag      = "crowdsec"
 	// ExploitSignatureTag is the tag of a request a rule file or the Core
 	// Rule Set matched.
 	ExploitSignatureTag = "exploitsignature"

internal/config/waf_test.go

@@ -65,8 +65,6 @@ const (
 	ipReputationCacheTTL           = "SWW_WAF_IP_REPUTATION_CACHE_TTL"
 	dnsblAbuseIPDBTimeout          = "SWW_WAF_DNSBL_ABUSEIPDB_TIMEOUT_MS"
 	routeWatchURL                  = "SWW_WAF_ROUTEWATCH_URL"
-	crowdSecURL                    = "SWW_WAF_CROWDSEC_LAPI_URL"
-	crowdSecKey                    = "SWW_WAF_CROWDSEC_LAPI_KEY"
 	banResponse                    = "SWW_WAF_BAN_RESPONSE"
 	limitBanDuration               = "SWW_WAF_LIMIT_BAN_DURATION"
 	limitBanRepeatWindow           = "SWW_WAF_LIMIT_BAN_REPEAT_WINDOW"
@@ -289,6 +287,7 @@ func TestDefaults(t *testing.T) {
 	})
 	wantLookupSettings(t, cfg, config.WAF{
 		LookupSource: defaultLookupSource, ASNAndCountryLookupTimeout: 800 * time.Millisecond,
+		AddLookupHeaders: true,
 	})
 	wantByteLimitSettings(t, cfg, config.WAF{
 		BytesLimitPerMinute: 0, BytesLimitPerHour: 50 << 30,
@@ -617,7 +616,7 @@ func TestCoreRuleSetSettings(t *testing.T) {
 				coreRuleSetScoreThreshold:     "10",
 				coreRuleSetDisabledRules:      "942100, 920350",
 				coreRuleSetExemptPaths:        "/api/, /static/",
-				coreRuleSetBodyInspectionSize: "32K",
+				coreRuleSetBodyInspectionSize: "4K",
 				exclusionsFile:                "/etc/sww/crs-exclusions.conf",
 			},
 			config.WAF{
@@ -626,7 +625,7 @@ func TestCoreRuleSetSettings(t *testing.T) {
 				CoreRuleSetScoreThreshold:     10,
 				CoreRuleSetDisabledRules:      []int{942100, 920350},
 				CoreRuleSetExemptPaths:        []string{"/api/", "/static/"},
-				CoreRuleSetBodyInspectionSize: 32 << 10,
+				CoreRuleSetBodyInspectionSize: 4 << 10,
 				CoreRuleSetExclusionsFile:     "/etc/sww/crs-exclusions.conf",
 			},
 		},
@@ -763,15 +762,15 @@ func TestInvalidAppsStopsTheStart(t *testing.T) {
 	}
 }
 
-func TestCoreRuleSetBodyInspectionSizeOf64K(t *testing.T) {
+func TestCoreRuleSetBodyInspectionSizeOf8K(t *testing.T) {
 	t.Parallel()
 
 	cfg := wafFromEnvironment(
 		t,
-		environment{coreRuleSetBodyInspectionSize: "64K"},
+		environment{coreRuleSetBodyInspectionSize: "8K"},
 	)
-	if cfg.CoreRuleSetBodyInspectionSize != 64<<10 {
-		t.Errorf("64K read as %d", cfg.CoreRuleSetBodyInspectionSize)
+	if cfg.CoreRuleSetBodyInspectionSize != 8<<10 {
+		t.Errorf("8K read as %d", cfg.CoreRuleSetBodyInspectionSize)
 	}
 }
 
@@ -820,11 +819,13 @@ func TestInvalidCoreRuleSetSettingStopsTheStart(t *testing.T) {
 			coreRuleSetBodyInspectionSize, "128KB",
 			`"128KB" is not a size such as 512K, 100M or 5G, or off`,
 		},
-		{coreRuleSetBodyInspectionSize, "65K", `"65K" is more than 64K, the most waf ` +
-			`gets of a body`},
 		{
-			coreRuleSetBodyInspectionSize, "65537",
-			`"65537" is more than 64K, the most waf gets of a body`,
+			coreRuleSetBodyInspectionSize, "9K",
+			`"9K" is more than 8K, the most the Core Rule Set can read in time`,
+		},
+		{
+			coreRuleSetBodyInspectionSize, "8193",
+			`"8193" is more than 8K, the most the Core Rule Set can read in time`,
 		},
 	} {
 		t.Run(tc.name+"="+tc.value, func(t *testing.T) {
@@ -1397,13 +1398,13 @@ func TestLookupSettingsAsSet(t *testing.T) {
 	t.Parallel()
 
 	cfg := wafFromEnvironment(t, environment{
-		asnAndCountryLookupTimeout: "500", addLookupHeaders: enabled,
+		asnAndCountryLookupTimeout: "500", addLookupHeaders: disabled,
 	})
 	wantLookupSettings(t, cfg, config.WAF{
 		LookupSource: defaultLookupSource, ASNAndCountryLookupTimeout: 500 * time.Millisecond,
-		AddLookupHeaders: true,
 	})
 
+	// With no client looked up, the headers are off unless set.
 	cfg = wafFromEnvironment(t, environment{lookupSource: off})
 	wantLookupSettings(t, cfg, config.WAF{
 		LookupSource: off, ASNAndCountryLookupTimeout: 800 * time.Millisecond,
@@ -1424,6 +1425,10 @@ func TestLookupDBPathGoesWithTheFileSourceAlone(t *testing.T) {
 			cfg.LookupSource, cfg.LookupDBPath, path)
 	}
 
+	if !cfg.AddLookupHeaders {
+		t.Error("headers off by default with lookups from file, want on")
+	}
+
 	for _, tc := range []struct {
 		env  environment
 		want string
@@ -1813,9 +1818,6 @@ func TestTagThatNoRequestCanGetIsToldApartFromOneItCan(t *testing.T) {
 			"abuseipdb with a key",
 			environment{abuseIPDBKey: "k", tagLimitPercent: "abuseipdb:50"}, "",
 		},
-		{"crowdsec, though a list has its name", environment{
-			tagLists: "crowdsec=https://example.com/c.txt", tagDeny: "crowdsec",
-		}, `"crowdsec" cannot be used`},
 		{exploitTag, environment{tagDeny: exploitTag}, ""},
 		{
 			exploitTag + " with rule files off",
@@ -1887,26 +1889,20 @@ func TestErrorOfATagSettingLeavesOutAZoneKey(t *testing.T) {
 func TestTagListURLFetchedAsAnotherListStopsTheStart(t *testing.T) {
 	t.Parallel()
 
-	const lapi = "http://172.17.0.1:8080"
-
 	for _, tc := range []struct {
 		name, listURL string
 		env           environment
 	}{
 		{"a blocklist", dropURL, environment{blocklistURLs: dropURL}},
 		{"the file of AS:percent lines", asnURL, environment{asnLimitPercentURL: asnURL}},
-		{
-			"the CrowdSec decision list", lapi + "/v1/decisions",
-			environment{"SWW_WAF_CROWDSEC_LAPI_URL": lapi, "SWW_WAF_CROWDSEC_LAPI_KEY": "key"},
-		},
 	} {
 		t.Run(tc.name, func(t *testing.T) {
 			t.Parallel()
 
 			tc.env[tagLists] = "dup=" + tc.listURL
 
-			want := tagLists + `: "` + tc.listURL + `" is in SWW_WAF_BLOCKLIST_URLS, is ` +
-				"SWW_WAF_ASN_LIMIT_PERCENT_URL or is the CrowdSec decision list too"
+			want := tagLists + `: "` + tc.listURL + `" is in SWW_WAF_BLOCKLIST_URLS ` +
+				"or is SWW_WAF_ASN_LIMIT_PERCENT_URL too"
 
 			_, err := config.WAFFromEnvironment(tc.env.viper())
 			if err == nil || err.Error() != want {
@@ -2456,138 +2452,6 @@ func TestAbuseIPDBKeyIsLoggedMasked(t *testing.T) {
 	}
 }
 
-func TestCrowdSecSettingsGiveTheDecisionListAndTheKey(t *testing.T) {
-	t.Parallel()
-
-	cfg := wafFromEnvironment(t, environment{})
-	if cfg.CrowdSecDecisionsURL != "" || cfg.CrowdSecKey != "" {
-		t.Errorf(
-			"by default, the decision list %q and the key %q, want neither",
-			cfg.CrowdSecDecisionsURL,
-			cfg.CrowdSecKey,
-		)
-	}
-
-	for lapi, want := range map[string]string{
-		"http://172.17.0.1:8080":          "http://172.17.0.1:8080/v1/decisions",
-		"http://172.17.0.1:8080/":         "http://172.17.0.1:8080/v1/decisions",
-		"https://crowdsec.example/lapi/":  "https://crowdsec.example/lapi/v1/decisions",
-		"https://crowdsec.example:8443/x": "https://crowdsec.example:8443/x/v1/decisions",
-	} {
-		cfg := wafFromEnvironment(
-			t,
-			environment{crowdSecURL: lapi, crowdSecKey: token},
-		)
-		if cfg.CrowdSecDecisionsURL != want || cfg.CrowdSecKey != token {
-			t.Errorf(
-				"%s=%s gave the decision list %q and the key %q, want %s and %s",
-				crowdSecURL,
-				lapi,
-				cfg.CrowdSecDecisionsURL,
-				cfg.CrowdSecKey,
-				want,
-				token,
-			)
-		}
-	}
-}
-
-func TestInvalidCrowdSecSettingStopsTheStartSayingWhatIsWrong(t *testing.T) {
-	t.Parallel()
-
-	const (
-		lapi       = "http://172.17.0.1:8080"
-		notLAPIURL = " is not an http or https URL without a user or a fragment, " +
-			"such as http://172.17.0.1:8080"
-		anotherList = `gives the decision list "` + lapi + `/v1/decisions", which is in ` +
-			`SWW_WAF_BLOCKLIST_URLS or is SWW_WAF_ASN_LIMIT_PERCENT_URL too`
-	)
-
-	for _, tc := range []struct {
-		name string
-		env  environment
-		want string
-	}{
-		{
-			"a URL that is not http",
-			environment{crowdSecURL: "ftp://172.17.0.1", crowdSecKey: token},
-			crowdSecURL + `: "ftp://172.17.0.1"` + notLAPIURL,
-		},
-		{
-			"a URL with a user",
-			environment{crowdSecURL: "http://bouncer@172.17.0.1:8080", crowdSecKey: token},
-			crowdSecURL + `: "http://bouncer@172.17.0.1:8080"` + notLAPIURL,
-		},
-		{
-			"the URL without the key",
-			environment{crowdSecURL: lapi},
-			crowdSecURL + ": is set while " + crowdSecKey + " is unset; the engine " +
-				"answers no request without it",
-		},
-		{
-			"the key without the URL",
-			environment{crowdSecKey: token},
-			crowdSecKey + ": is set while " + crowdSecURL + " is unset; it is sent only " +
-				"to the engine at that URL",
-		},
-		{
-			"the decision list as a blocklist too",
-			environment{
-				crowdSecURL: lapi, crowdSecKey: token,
-				blocklistURLs: "https://lists.example/drop.txt," + lapi + "/v1/decisions",
-			},
-			crowdSecURL + ": " + anotherList,
-		},
-		{
-			"the decision list as the file of AS:percent lines too",
-			environment{
-				crowdSecURL: lapi + "/", crowdSecKey: token,
-				asnLimitPercentURL: lapi + "/v1/decisions",
-			},
-			crowdSecURL + ": " + anotherList,
-		},
-		// The key itself is never shown.
-		{
-			"a key with a control character",
-			environment{crowdSecURL: lapi, crowdSecKey: token + "\r"},
-			crowdSecKey + ": holds a control character, such as the carriage return " +
-				"of a Windows line end",
-		},
-	} {
-		t.Run(tc.name, func(t *testing.T) {
-			t.Parallel()
-
-			_, err := config.WAFFromEnvironment(tc.env.viper())
-			if err == nil || err.Error() != tc.want {
-				t.Errorf("error %v, want %s", err, tc.want)
-			}
-		})
-	}
-}
-
-func TestCrowdSecKeyIsLoggedMasked(t *testing.T) {
-	t.Parallel()
-
-	cfg := wafFromEnvironment(t, environment{
-		crowdSecURL: "http://172.17.0.1:8080", crowdSecKey: token,
-	})
-
-	var out bytes.Buffer
-
-	slog.New(slog.NewJSONHandler(&out, nil)).
-		Info("starting", "settings", cfg)
-
-	logged := out.String()
-	if strings.Contains(logged, token) ||
-		!strings.Contains(logged, `"`+crowdSecKey+`":"********"`) ||
-		!strings.Contains(
-			logged,
-			`"`+crowdSecURL+`":"http://172.17.0.1:8080"`,
-		) {
-		t.Errorf("the key is not logged masked beside the URL: %s", logged)
-	}
-}
-
 func TestSizesAndOff(t *testing.T) {
 	t.Parallel()
 
@@ -2714,10 +2578,10 @@ func TestInvalidLookupTagOrLogValueStopsTheStart(t *testing.T) {
 		{tagDeny, "a,,b"}, {tagDeny, "country=nk"}, {tagDeny, "asn=abc"},
 		{tagDeny, "asn="},
 		{tagDeny, "torexit,TOREXIT"}, {tagDeny, "torexti"},
-		{tagDeny, zenTag}, {tagDeny, "abuseipdb"}, {tagDeny, "crowdsec"},
+		{tagDeny, zenTag}, {tagDeny, "abuseipdb"},
 		{tagLimitPercent, "torexti:50"},
 		{tagLimitPercent, "dnsbl=zen.example:50"},
-		{tagLimitPercent, "abuseipdb:50"}, {tagLimitPercent, "crowdsec:50"},
+		{tagLimitPercent, "abuseipdb:50"},
 		{tagLimitPercent, "vpn :50"},
 		{tagLimitPercent, "vpn"}, {tagLimitPercent, ":50"},
 		{tagLimitPercent, "vpn:"},
@@ -3070,7 +2934,7 @@ func TestLogsEachSettingWithItsValue(t *testing.T) {
 		lookupSource:                   defaultLookupSource,
 		lookupDBPath:                   "",
 		asnAndCountryLookupTimeout:     "800",
-		addLookupHeaders:               disabled,
+		addLookupHeaders:               enabled,
 		allowedCountries:               "",
 		tagLists:                       "",
 		tagDeny:                        "",
@@ -3091,8 +2955,6 @@ func TestLogsEachSettingWithItsValue(t *testing.T) {
 		ipReputationCacheTTL:           defaultIPReputationCacheTTL,
 		dnsblAbuseIPDBTimeout:          "2000",
 		routeWatchURL:                  "",
-		crowdSecURL:                    "",
-		crowdSecKey:                    "",
 		banResponse:                    "403",
 		limitBanDuration:               "1h",
 		limitBanRepeatWindow:           "24h",

internal/coreruleset/coreruleset.go

@@ -481,12 +481,21 @@ func (c *CoreRuleSet) Inspect(
 	return Result{RuleIDs: ids, Score: score(tx)}, read, err
 }
 
+// mostJSONRead is the largest JSON body the Core Rule Set reads, even while
+// SWW_WAF_CORE_RULE_SET_BODY_INSPECTION_SIZE is larger. Coraza names each
+// value in a JSON body by the whole path to it, so what it gives the Core
+// Rule Set to read can outgrow the body: up to 8 times its size, and up to
+// 4 KiB for a small body. 1 KiB of JSON thus gives at most 8 KiB, no more
+// than the largest body of another kind.
+const mostJSONRead = 1 << 10
+
 // readBody reads body, the body of the request in tx, which has run on
 // the request's headers, while SWW_WAF_CORE_RULE_SET_BODY_INSPECTION_SIZE is
 // set and the body is of a kind the Core Rule Set reads: form data and
 // multipart, of which it reads the first c.bodyInspectionSize bytes, and
 // JSON and XML, which it reads only when they are no longer than that,
-// since they cannot be read in part.
+// since they cannot be read in part. The Core Rule Set reads no JSON body
+// longer than mostJSONRead either.
 // readBody reads one byte past c.bodyInspectionSize, to tell which they
 // are, gives the Core Rule Set what it reads, and returns what it read and
 // the error that ended the reading early, if one did.
@@ -499,6 +508,8 @@ func (c *CoreRuleSet) readBody(
 	}
 
 	inPart := false
+	// largest is the largest JSON or XML body the Core Rule Set reads.
+	largest := c.bodyInspectionSize
 	// How the body is read is a variable of the transaction, which only
 	// Coraza's interface for plugins reads.
 	state := tx.(plugintypes.TransactionState) //nolint:forcetypeassert // every one is
@@ -506,14 +517,16 @@ func (c *CoreRuleSet) readBody(
 	switch state.Variables().RequestBodyProcessor().Get() {
 	case "URLENCODED", "MULTIPART":
 		inPart = true
-	case "JSON", "XML":
+	case "JSON":
+		largest = min(largest, mostJSONRead)
+	case "XML":
 	default:
 		return nil, nil
 	}
 
 	read, err := io.ReadAll(io.LimitReader(body, c.bodyInspectionSize+1))
 
-	if inPart || (err == nil && int64(len(read)) <= c.bodyInspectionSize) {
+	if inPart || (err == nil && int64(len(read)) <= largest) {
 		// Coraza holds what it reads of the body in memory, up to the
 		// limit, so this cannot fail.
 		_, _, _ = tx.WriteRequestBody(read)

internal/coreruleset/coreruleset_test.go

@@ -390,22 +390,15 @@ func TestMoreParametersThanCorazaKeepsIsAMatch(t *testing.T) {
 		matched(900300),
 	)
 
-	// So it is with the fields of a form data or JSON body.
+	// So it is with the fields of a form data body. A JSON body the Core
+	// Rule Set reads, of at most mostJSONRead bytes, cannot hold that many.
 	crs = readingBodies(t)
 
-	for _, tc := range []struct{ header, body string }{
-		{formData, strings.Repeat("a=1&", 999) + attack},
-		{jsonBody, `{"a":[` + strings.Repeat("1,", 998) + `1],"id":"` + injection + `"}`},
-	} {
-		wantBody(t, crs, post(tc.header), tc.body, matched(942100), tc.body)
-	}
+	body := strings.Repeat("a=1&", 999) + attack
+	wantBody(t, crs, post(formData), body, matched(942100), body)
 
-	for _, tc := range []struct{ header, body string }{
-		{formData, strings.Repeat("a=1&", 1000) + attack},
-		{jsonBody, `{"a":[` + strings.Repeat("1,", 999) + `1],"id":"` + injection + `"}`},
-	} {
-		wantBody(t, crs, post(tc.header), tc.body, matched(900300), tc.body)
-	}
+	body = strings.Repeat("a=1&", 1000) + attack
+	wantBody(t, crs, post(formData), body, matched(900300), body)
 }
 
 func TestRedirectURIMayNameALocalAddress(t *testing.T) {
@@ -1512,13 +1505,15 @@ const (
 	wpTags    = "/wp-json/wp/v2/tags"
 )
 
-// readingBodiesUpTo64K returns the Core Rule Set as sww runs it by default,
+// readingBodiesUpTo8K returns the Core Rule Set as sww runs it by default,
 // but reading bodies up to the largest SWW_WAF_CORE_RULE_SET_BODY_INSPECTION_SIZE.
-func readingBodiesUpTo64K(t *testing.T) *coreruleset.CoreRuleSet {
+func readingBodiesUpTo8K(t *testing.T) *coreruleset.CoreRuleSet {
 	t.Helper()
 
 	return shared(t, coreruleset.Params{
-		ParanoiaLevel: 1, DisabledRules: defaultDisabledRules, BodyInspectionSize: 64<<10 - 1,
+		ParanoiaLevel:      1,
+		DisabledRules:      defaultDisabledRules,
+		BodyInspectionSize: mostBodyRead,
 	})
 }
 
@@ -1582,7 +1577,7 @@ func TestWordPressAttacksAreRefused(t *testing.T) {
 
 	const threshold = 5 // SWW_WAF_CORE_RULE_SET_SCORE_THRESHOLD's default
 
-	defaults, bodies := atDefaults(t), readingBodiesUpTo64K(t)
+	defaults, bodies := atDefaults(t), readingBodiesUpTo8K(t)
 
 	for _, attack := range []string{
 		sqlInjection,
@@ -1693,7 +1688,7 @@ func wordpressRESTAddresses(route string) []string {
 func TestWordPressExclusionsFollowEveryRESTAddress(t *testing.T) {
 	t.Parallel()
 
-	crs := readingBodiesUpTo64K(t)
+	crs := readingBodiesUpTo8K(t)
 	content := `{"content":"` + wordpressBlock + `"}`
 
 	for _, route := range []string{
@@ -1919,7 +1914,7 @@ func TestWordPressCommandAfterASeparatorIsRefusedOnSearchesAndNames(
 		wantResult(t, crs, get(target+command), matched(932235))
 	}
 
-	bodies := readingBodiesUpTo64K(t)
+	bodies := readingBodiesUpTo8K(t)
 
 	for _, p := range wordpressBodyFields(command) {
 		r := request{http.MethodPost, p.target, []string{p.contentType}}
@@ -2143,7 +2138,7 @@ func TestWordPressBodyFieldsAreCheckedInTheQuery(t *testing.T) {
 func TestWordPressBodyNamesAndAddressesAreExcludedOnlyThere(t *testing.T) {
 	t.Parallel()
 
-	crs := readingBodiesUpTo64K(t)
+	crs := readingBodiesUpTo8K(t)
 
 	for _, v := range wordpressWords() {
 		for _, field := range []string{"title", "excerpt", "name"} {
@@ -2262,7 +2257,7 @@ func TestWordPressExclusionsAreNarrow(t *testing.T) {
 		length  = "Content-Length: 2"
 	)
 
-	crs := readingBodiesUpTo64K(t)
+	crs := readingBodiesUpTo8K(t)
 	saving := request{
 		http.MethodPost,
 		wpPost,
@@ -2473,19 +2468,35 @@ func TestFormDataAndMultipartAreReadUpToTheLimit(t *testing.T) {
 func TestJSONAndXMLAreReadOnlyWhenNoLargerThanTheLimit(t *testing.T) {
 	t.Parallel()
 
-	crs := readingBodies(t)
+	// The limit is the body inspection size, but at most mostJSONRead for
+	// JSON. smallSize is a body inspection size under mostJSONRead.
+	const smallSize = 512
 
-	for _, tc := range []struct{ header, head, tail string }{
-		{jsonBody, `{"q":"` + injection + `","pad":"`, `"}`},
-		{xmlBody, "<r><q>" + injection + "</q><pad>", "</pad></r>"},
+	bodies, smallBodies := readingBodies(t), shared(t, coreruleset.Params{
+		ParanoiaLevel: 1, DisabledRules: defaultDisabledRules,
+		BodyInspectionSize: smallSize,
+	})
+	jsonHead, jsonTail := `{"q":"`+injection+`","pad":"`, `"}`
+
+	for _, tc := range []struct {
+		crs                *coreruleset.CoreRuleSet
+		header, head, tail string
+		limit              int
+	}{
+		{bodies, jsonBody, jsonHead, jsonTail, mostJSONRead},
+		{smallBodies, jsonBody, jsonHead, jsonTail, smallSize},
+		{
+			bodies, xmlBody, "<r><q>" + injection + "</q><pad>", "</pad></r>",
+			bodyInspectionSize,
+		},
 	} {
-		fits := padded(tc.head, tc.tail, bodyInspectionSize)
-		wantBody(t, crs, post(tc.header), fits, matched(942100), fits)
+		fits := padded(tc.head, tc.tail, tc.limit)
+		wantBody(t, tc.crs, post(tc.header), fits, matched(942100), fits)
 
-		larger := padded(tc.head, tc.tail, bodyInspectionSize+1)
+		larger := padded(tc.head, tc.tail, tc.limit+1)
 		wantBody(
 			t,
-			crs,
+			tc.crs,
 			post(tc.header),
 			larger,
 			coreruleset.Result{},

internal/coreruleset/inspectiontime_test.go

@@ -0,0 +1,371 @@
+package coreruleset_test
+
+import (
+	"maps"
+	"net/http"
+	"net/http/httptest"
+	"net/netip"
+	"slices"
+	"strconv"
+	"strings"
+	"testing"
+	"time"
+
+	"sneak.berlin/go/smallwebwaf/internal/coreruleset"
+)
+
+// The bounds on what a visitor can send, as SPEC.md gives them.
+const (
+	// lineLimit is the longest request line or header line.
+	lineLimit = 8 << 10
+	// headerLimit is the most bytes rproxy reads of a request line and
+	// headers together.
+	headerLimit = 32 << 10
+	// mostCookies and mostHeaderFields are waf's limits on cookies and header
+	// fields.
+	mostCookies      = 50
+	mostHeaderFields = 100
+	// mostBodyRead is the largest SWW_WAF_CORE_RULE_SET_BODY_INSPECTION_SIZE.
+	mostBodyRead = 8 << 10
+	// mostJSONRead is the largest JSON body the Core Rule Set reads.
+	mostJSONRead = 1 << 10
+)
+
+// inspectionTimeLimit is the most time the Core Rule Set may take on one
+// request. It is the default of rproxy's SWW_RPROXY_WAF_BACKEND_TIMEOUT_MS, 2
+// seconds, less the default of SWW_WAF_ASN_AND_COUNTRY_LOOKUP_TIMEOUT_MS, 800
+// milliseconds, which a question can also wait for GeoJS, and less 200
+// milliseconds for waf's other checks.
+const inspectionTimeLimit = time.Second
+
+// text returns n bytes of letters, digits and spaces, which the Core Rule Set
+// takes longer over than one letter repeated.
+func text(n int) string {
+	const words = "select 0x2f from tbl_1 where name like abc_9 "
+
+	return strings.Repeat(words, n/len(words)+1)[:n]
+}
+
+// visitorRequest is a request a visitor can send, at the most of one or more
+// of the bounds above.
+type visitorRequest struct {
+	name   string
+	target string
+	// header holds the headers besides Host.
+	header http.Header
+	// contentType is the body's type, "" for no body.
+	contentType string
+	body        string
+}
+
+// longestTarget returns a target whose request line, "POST <target>
+// HTTP/1.1", is lineLimit bytes long.
+func longestTarget() string {
+	const around = len("POST /?q= HTTP/1.1")
+
+	return "/?q=" + strings.ReplaceAll(text(lineLimit-around), " ", "+")
+}
+
+// cookieLine returns a Cookie value whose line, "Cookie: <value>", is
+// lineLimit bytes long, made of count cookies.
+func cookieLine(count int) string {
+	const linePrefix = len("Cookie: ")
+
+	cookies := make([]string, count)
+	for i := range cookies {
+		cookies[i] = "c" + strconv.Itoa(i) + "="
+	}
+
+	// Each cookie is followed by "; ", but for the last.
+	room := lineLimit - linePrefix - len(strings.Join(cookies, "; "))
+	for i := range cookies {
+		share := room / count
+		if i == 0 {
+			share += room % count
+		}
+
+		cookies[i] += strings.ReplaceAll(text(share), " ", "_")
+	}
+
+	return strings.Join(cookies, "; ")
+}
+
+// headerValue returns a value whose line, "<name>: <value>", is n bytes long.
+func headerValue(name string, n int) string {
+	return text(n - len(name) - len(": "))
+}
+
+// formFields returns a form body of mostBodyRead bytes holding count fields.
+func formFields(count int) string {
+	fields := make([]string, count)
+	for i := range fields {
+		fields[i] = "f" + strconv.Itoa(i) + "="
+	}
+
+	room := mostBodyRead - len(strings.Join(fields, "&"))
+	for i := range fields {
+		share := room / count
+		if i == 0 {
+			share += room % count
+		}
+
+		fields[i] += strings.ReplaceAll(text(share), " ", "+")
+	}
+
+	return strings.Join(fields, "&")
+}
+
+// multipartBody returns a multipart body of mostBodyRead bytes, with the
+// boundary "b", holding fields of about size bytes each.
+func multipartBody(size int) string {
+	var body strings.Builder
+
+	const end = "--b--\r\n"
+
+	for i := 0; ; i++ {
+		head := "--b\r\nContent-Disposition: form-data; name=\"f" +
+			strconv.Itoa(i) + "\"\r\n\r\n"
+
+		room := mostBodyRead - body.Len() - len(
+			end,
+		) - len(
+			head,
+		) - len(
+			"\r\n",
+		)
+		if room <= 0 {
+			break
+		}
+
+		body.WriteString(head + text(min(size, room)) + "\r\n")
+	}
+
+	body.WriteString(end)
+
+	return body.String()
+}
+
+// jsonArrayOfMostElements returns a JSON array of at most mostJSONRead bytes
+// holding as many elements as fit, each the number 1.
+func jsonArrayOfMostElements() string {
+	return "[1" + strings.Repeat(
+		",1",
+		(mostJSONRead-len("[1]"))/len(",1"),
+	) + "]"
+}
+
+// jsonOfMostElementsUnderAKey returns a JSON body of mostJSONRead bytes
+// holding as many elements as fit, each the number 1, in an array under a
+// key of 6 bytes. Coraza names each element "json.<key>.<index>", so a
+// longer key makes longer names. 6 bytes is the longest key that keeps the
+// names and values of this body within the 8 KiB Coraza allows.
+func jsonOfMostElementsUnderAKey() string {
+	head := `{"` + text(6) + `":[1`
+
+	return head + strings.Repeat(
+		",1",
+		(mostJSONRead-len(head+"]}"))/len(",1"),
+	) + "]}"
+}
+
+// The kinds of body the Core Rule Set reads, and the header that names a
+// request's cookies.
+const (
+	formType      = "application/x-www-form-urlencoded"
+	jsonType      = "application/json"
+	multipartType = "multipart/form-data; boundary=b"
+	cookieHeader  = "Cookie"
+)
+
+// fullLine is the length of each of the request line and the three or four
+// header lines that together fill rproxy's limit, with room for the line
+// endings and the other headers.
+const fullLine = lineLimit - 64
+
+// worstCaseRequests are, for each kind of thing a visitor sends, the requests
+// that keep the Core Rule Set busiest, within the bounds above. The last
+// holds the most of everything at once: Cookie lines keep it busier than
+// other header lines, and the JSON body of the most elements under a key
+// keeps it busier than the other bodies.
+func worstCaseRequests() []visitorRequest {
+	fullCookieLine := cookieLine(1)[:fullLine-len("Cookie: ")]
+
+	return append(
+		append(worstCaseHeaders(), worstCaseBodies()...),
+		visitorRequest{
+			name:   "the longest request line, three Cookie lines and body",
+			target: longestTarget()[:fullLine-len("POST  HTTP/1.1")],
+			header: http.Header{cookieHeader: {
+				fullCookieLine, fullCookieLine, fullCookieLine,
+			}},
+			contentType: jsonType, body: jsonOfMostElementsUnderAKey(),
+		},
+	)
+}
+
+// worstCaseHeaders are the requests of worstCaseRequests with no body.
+func worstCaseHeaders() []visitorRequest {
+	headerFields := http.Header{}
+
+	for i := range mostHeaderFields - 1 {
+		name := "X-Field-" + strconv.Itoa(i)
+		headerFields.Set(
+			name,
+			headerValue(name, headerLimit/mostHeaderFields),
+		)
+	}
+
+	return []visitorRequest{
+		{name: "the longest request line", target: longestTarget()},
+		{
+			name: "the longest request line, as query parameters",
+			target: "/?" + strings.Repeat(
+				"a=1&",
+				(lineLimit-len("POST /? HTTP/1.1"))/len("a=1&"),
+			),
+		},
+		{
+			name:   "the longest Cookie line, as one cookie",
+			target: "/",
+			header: http.Header{cookieHeader: {cookieLine(1)}},
+		},
+		{
+			name:   "the longest Cookie line, as the most cookies",
+			target: "/",
+			header: http.Header{cookieHeader: {cookieLine(mostCookies)}},
+		},
+		{name: "the most header fields", target: "/", header: headerFields},
+		{
+			name:   "the longest header lines",
+			target: "/",
+			header: http.Header{
+				"User-Agent": {headerValue("User-Agent", fullLine)},
+				"Referer":    {headerValue("Referer", fullLine)},
+				"Accept":     {headerValue("Accept", fullLine)},
+				"X-Long":     {headerValue("X-Long", fullLine)},
+			},
+		},
+	}
+}
+
+// worstCaseBodies are the requests of worstCaseRequests whose body holds
+// the most the Core Rule Set reads.
+func worstCaseBodies() []visitorRequest {
+	const nested = (mostJSONRead - len(`{"a":1}`)) / len(`{"a":}`)
+
+	return []visitorRequest{
+		{
+			name: "a form body of one field", target: "/",
+			contentType: formType, body: formFields(1),
+		},
+		{
+			name: "a form body of the most fields Coraza keeps", target: "/",
+			contentType: formType, body: formFields(1000),
+		},
+		{
+			name: "a JSON body of one string", target: "/",
+			contentType: jsonType,
+			body: `{"a":"` + text(
+				mostJSONRead-len(`{"a":""}`),
+			) + `"}`,
+		},
+		{
+			name: "a JSON body of the most elements", target: "/",
+			contentType: jsonType, body: jsonArrayOfMostElements(),
+		},
+		{
+			name: "a JSON body of the most elements under a key", target: "/",
+			contentType: jsonType, body: jsonOfMostElementsUnderAKey(),
+		},
+		{
+			name: "a JSON body nested deep", target: "/",
+			contentType: jsonType,
+			body: strings.Repeat(`{"a":`, nested) + "1" +
+				strings.Repeat("}", nested),
+		},
+		{
+			name: "an XML body of many elements", target: "/",
+			contentType: "application/xml",
+			body: "<a>" + strings.Repeat(
+				"<b>x</b>",
+				(mostBodyRead-len("<a></a>"))/len("<b>x</b>"),
+			) + "</a>",
+		},
+		{
+			name: "a multipart body of one field", target: "/",
+			contentType: multipartType, body: multipartBody(mostBodyRead),
+		},
+		{
+			name: "a multipart body of many fields", target: "/",
+			contentType: multipartType, body: multipartBody(1),
+		},
+	}
+}
+
+// inspectionTime returns how long crs takes to inspect tc, and fails t unless
+// it reads all of tc's body and Coraza parses it.
+func inspectionTime(
+	t *testing.T, crs *coreruleset.CoreRuleSet, tc visitorRequest,
+) time.Duration {
+	t.Helper()
+
+	req := httptest.NewRequestWithContext(
+		t.Context(), http.MethodPost, tc.target, nil,
+	)
+	maps.Copy(req.Header, tc.header)
+
+	if tc.contentType != "" {
+		req.Header.Set("Content-Type", tc.contentType)
+	}
+
+	began := time.Now()
+	result, read, _ := crs.Inspect(
+		req, netip.MustParseAddr("192.0.2.1"), strings.NewReader(tc.body),
+	)
+	took := time.Since(began)
+
+	if string(read) != tc.body {
+		t.Errorf("read %d bytes of %d", len(read), len(tc.body))
+	}
+
+	// Rule 900440 matches a body Coraza could not parse.
+	if slices.Contains(result.RuleIDs, 900440) {
+		t.Errorf("Coraza could not parse the body")
+	}
+
+	return took
+}
+
+// TestTheCoreRuleSetInspectsEachWorstCaseRequestInTime runs one at a time, so
+// that the tests running in parallel do not slow it. Other work on the host
+// can still slow one try, so a request fails only when three tries in a row
+// take too long.
+//
+//nolint:paralleltest // one at a time, as above
+func TestTheCoreRuleSetInspectsEachWorstCaseRequestInTime(t *testing.T) {
+	const tries = 3
+
+	// The settings that make the Core Rule Set slowest: the highest paranoia
+	// level, no rule switched off, and the most of a body read.
+	crs := shared(t, coreruleset.Params{
+		ParanoiaLevel: 4, BodyInspectionSize: mostBodyRead,
+	})
+
+	for _, tc := range worstCaseRequests() {
+		t.Run(tc.name, func(t *testing.T) {
+			var took time.Duration
+
+			for range tries {
+				took = inspectionTime(t, crs, tc)
+				if took <= inspectionTimeLimit {
+					return
+				}
+			}
+
+			t.Errorf(
+				"took %s on the last of %d tries, over %s",
+				took, tries, inspectionTimeLimit,
+			)
+		})
+	}
+}

internal/metrics/metrics.go

@@ -185,7 +185,7 @@ func (m *Metrics) AddBansAndClients(
 	ledger *bans.Ledger, limiter *ratelimit.Limiter, now func() time.Time,
 ) {
 	for _, cause := range []string{
-		bans.CauseLimit, bans.CauseAttack, bans.CauseAdmin, bans.CauseCrowdSec,
+		bans.CauseLimit, bans.CauseAttack, bans.CauseAdmin,
 	} {
 		m.registry.MustRegister(
 			prometheus.NewCounterFunc(prometheus.CounterOpts{
@@ -302,20 +302,20 @@ const sourceLabel = "source"
 
 // AddReputation adds the metrics of the lists fetched from URLs and of the
 // DNSBL zones, by source, each list's URL or each zone, its key masked as
-// config.MaskZoneKey masks it: the requests whose client a blocklist, the
-// CrowdSec decision list, a zone's verdict or AbuseIPDB's score lists,
-// which ReputationHit counts, and, read from lists and dnsbl as the
-// metrics are asked for, for a list, the fetches that failed and when the
-// copy in use was fetched, and for a zone, the queries made and those that
-// failed. It is called once, before ReputationHit.
+// config.MaskZoneKey masks it: the requests whose client a blocklist, a
+// zone's verdict or AbuseIPDB's score lists, which ReputationHit counts,
+// and, read from lists and dnsbl as the metrics are asked for, for a list,
+// the fetches that failed and when the copy in use was fetched, and for a
+// zone, the queries made and those that failed. It is called once, before
+// ReputationHit.
 func (m *Metrics) AddReputation(
 	lists *reputation.Lists,
 	dnsbl *reputation.DNSBL,
 ) {
 	m.reputationHits = counterVec(
 		"sww_reputation_hits_total",
-		"Requests whose client a blocklist, the CrowdSec decision list, a DNSBL "+
-			"zone or AbuseIPDB lists, by the list's URL, the zone, or abuseipdb.",
+		"Requests whose client a blocklist, a DNSBL zone or AbuseIPDB lists, "+
+			"by the list's URL, the zone, or abuseipdb.",
 		[]string{sourceLabel},
 	)
 	m.registry.MustRegister(m.reputationHits)
@@ -378,9 +378,8 @@ func (m *Metrics) AddAbuseIPDB(abuseIPDB *reputation.AbuseIPDB) {
 	)
 }
 
-// ReputationHit counts a request whose client source lists: a blocklist
-// or the CrowdSec decision list, by its URL, a DNSBL zone, its key masked,
-// or AbuseIPDB, abuseipdb.
+// ReputationHit counts a request whose client source lists: a blocklist,
+// by its URL, a DNSBL zone, its key masked, or AbuseIPDB, abuseipdb.
 func (m *Metrics) ReputationHit(source string) {
 	m.reputationHits.WithLabelValues(source).Inc()
 }

internal/reputation/crowdsec_test.go

@@ -1,622 +0,0 @@
-package reputation_test
-
-import (
-	"bytes"
-	"encoding/json"
-	"fmt"
-	"io"
-	"log/slog"
-	"net/http"
-	"net/netip"
-	"reflect"
-	"strings"
-	"sync"
-	"testing"
-	"testing/synctest"
-	"time"
-
-	"sneak.berlin/go/smallwebwaf/internal/alerts"
-	"sneak.berlin/go/smallwebwaf/internal/reputation"
-)
-
-// The tests run in a synctest bubble, as those of the blocklists do, and
-// fetch the decision list from engine, a stand-in for a CrowdSec engine
-// that answers without the network.
-
-const (
-	// decisionsURL is the decision list of the tests' engine, and engineKey
-	// the key it answers.
-	decisionsURL = "http://crowdsec.example:8080/v1/decisions"
-	engineKey    = "crowdsec-key-0123456789abcdef"
-	// sshBF and probing are scenarios of the engine's decisions.
-	sshBF   = "crowdsecurity/ssh-bf"
-	probing = "crowdsecurity/http-probing"
-	// ban is the type of a decision to ban, and rangeScope the scope of a
-	// decision on a netblock, as CrowdSec names them.
-	ban        = "ban"
-	rangeScope = "Range"
-)
-
-func TestCrowdSecDecisionBansItsNetblockUntilItEndsEvenWithTheEngineDown(
-	t *testing.T,
-) {
-	t.Parallel()
-
-	synctest.Test(t, func(t *testing.T) {
-		began := time.Now()
-		manual := "manual 'ban' from 'localhost'"
-		e := &engine{key: engineKey, decisions: []decision{
-			{"Ip", suspect, ban, manual, began.Add(6 * time.Hour)},
-			// A shorter decision on the same address, which is not the one
-			// used.
-			{"Ip", suspect, ban, sshBF, began.Add(4 * time.Hour)},
-			{
-				rangeScope,
-				"198.51.100.0/24",
-				ban,
-				probing,
-				began.Add(time.Hour),
-			},
-			{"Ip", "2001:db8::1", ban, sshBF, began.Add(2 * time.Hour)},
-			// Left out: a decision to show a captcha, and one on a country.
-			{"Ip", "192.0.2.50", "captcha", probing, began.Add(time.Hour)},
-			{"Country", "KP", ban, manual, began.Add(time.Hour)},
-		}}
-		lists := start(t, e, crowdSecParams())
-
-		for addr, want := range map[string]reputation.Decision{
-			suspect:          {Expires: began.Add(6 * time.Hour), Scenario: manual},
-			"198.51.100.0":   {Expires: began.Add(time.Hour), Scenario: probing},
-			"198.51.100.255": {Expires: began.Add(time.Hour), Scenario: probing},
-			"2001:db8::1":    {Expires: began.Add(2 * time.Hour), Scenario: sshBF},
-			"203.0.113.10":   {},
-			"198.51.101.0":   {},
-			"2001:db8::2":    {},
-			"192.0.2.50":     {},
-		} {
-			wantDecision(t, lists, addr, want)
-		}
-
-		// With the engine down, the copy kept still holds the decision on
-		// 198.51.100.0/24, which no longer bans once it has ended.
-		e.set(func(e *engine) { e.failing = true })
-		time.Sleep(time.Hour - time.Nanosecond)
-		synctest.Wait()
-		wantDecision(
-			t,
-			lists,
-			"198.51.100.7",
-			reputation.Decision{
-				Expires:  began.Add(time.Hour),
-				Scenario: probing,
-			},
-		)
-
-		time.Sleep(time.Nanosecond)
-		synctest.Wait()
-		wantDecision(t, lists, "198.51.100.7", reputation.Decision{})
-		wantDecision(
-			t,
-			lists,
-			suspect,
-			reputation.Decision{
-				Expires:  began.Add(6 * time.Hour),
-				Scenario: manual,
-			},
-		)
-	})
-}
-
-func TestCrowdSecDecisionListFetchedAgainEveryMinute(t *testing.T) {
-	t.Parallel()
-
-	synctest.Test(t, func(t *testing.T) {
-		began := time.Now()
-		e := &engine{key: engineKey, decisions: []decision{
-			{"Ip", suspect, ban, sshBF, began.Add(4 * time.Hour)},
-		}}
-		lists := start(t, e, crowdSecParams())
-		wantEngineFetches(t, e, 1)
-
-		added := reputation.Decision{
-			Expires:  began.Add(2 * time.Hour),
-			Scenario: probing,
-		}
-
-		e.set(func(e *engine) {
-			e.decisions = append(e.decisions,
-				decision{"Ip", "203.0.113.10", ban, probing, added.Expires})
-		})
-
-		time.Sleep(time.Minute - time.Nanosecond)
-		wantEngineFetches(t, e, 1)
-		wantDecision(t, lists, "203.0.113.10", reputation.Decision{})
-
-		time.Sleep(time.Nanosecond)
-		wantEngineFetches(t, e, 2)
-		wantDecision(t, lists, "203.0.113.10", added)
-	})
-}
-
-func TestCrowdSecDecisionOnAClientIsTheOneThatEndsLast(t *testing.T) {
-	t.Parallel()
-
-	synctest.Test(t, func(t *testing.T) {
-		began := time.Now()
-		e := &engine{key: engineKey, decisions: []decision{
-			// Two decisions on one address, the shorter listed first.
-			{"Ip", suspect, ban, sshBF, began.Add(2 * time.Hour)},
-			{"Ip", suspect, ban, probing, began.Add(4 * time.Hour)},
-			// 198.51.100.130 is held by a decision on its address that ends
-			// after the one on its netblock, and 192.0.2.20 by one that ends
-			// before.
-			{
-				rangeScope,
-				"198.51.100.128/25",
-				ban,
-				sshBF,
-				began.Add(time.Hour),
-			},
-			{"Ip", "198.51.100.130", ban, probing, began.Add(3 * time.Hour)},
-			{
-				rangeScope,
-				"192.0.2.0/24",
-				ban,
-				probing,
-				began.Add(5 * time.Hour),
-			},
-			{"Ip", "192.0.2.20", ban, sshBF, began.Add(2 * time.Hour)},
-		}}
-		lists := start(t, e, crowdSecParams())
-
-		wantDecision(
-			t,
-			lists,
-			suspect,
-			reputation.Decision{
-				Expires:  began.Add(4 * time.Hour),
-				Scenario: probing,
-			},
-		)
-		wantDecision(
-			t,
-			lists,
-			"198.51.100.130",
-			reputation.Decision{
-				Expires:  began.Add(3 * time.Hour),
-				Scenario: probing,
-			},
-		)
-		wantDecision(
-			t,
-			lists,
-			"192.0.2.20",
-			reputation.Decision{
-				Expires:  began.Add(5 * time.Hour),
-				Scenario: probing,
-			},
-		)
-	})
-}
-
-func TestCrowdSecAnswerOfNoDecisionIsAGoodCopyThatListsNoClient(
-	t *testing.T,
-) {
-	t.Parallel()
-
-	synctest.Test(t, func(t *testing.T) {
-		began := time.Now()
-		e := &engine{key: engineKey, decisions: []decision{
-			{"Ip", suspect, ban, sshBF, began.Add(4 * time.Hour)},
-		}}
-		lists := start(t, e, crowdSecParams())
-
-		// With its decision deleted, the engine answers null.
-		e.set(func(e *engine) { e.decisions = nil })
-		time.Sleep(time.Minute)
-		wantEngineFetches(t, e, 2)
-
-		want := []reputation.List{{
-			URL: decisionsURL, Tried: time.Now(), Fetched: time.Now(), Lines: []string{"null"},
-		}}
-		if got := lists.Snapshot(); !reflect.DeepEqual(got, want) {
-			t.Errorf("lists %+v, want %+v", got, want)
-		}
-
-		if lists.Failures(decisionsURL) != 0 {
-			t.Errorf("%d failures, want 0", lists.Failures(decisionsURL))
-		}
-
-		wantDecision(t, lists, suspect, reputation.Decision{})
-	})
-}
-
-func TestCrowdSecFailureKeepsTheLastGoodCopyAlertsOncePerCooldownAndHidesTheKey(
-	t *testing.T,
-) {
-	t.Parallel()
-
-	for _, tc := range crowdSecFailures() {
-		t.Run(tc.name, func(t *testing.T) {
-			t.Parallel()
-
-			synctest.Test(t, func(t *testing.T) {
-				var log bytes.Buffer
-
-				began := time.Now()
-				e := &engine{key: engineKey, decisions: []decision{
-					{"Ip", suspect, ban, sshBF, began.Add(4 * time.Hour)},
-				}}
-				queue := newQueue()
-				p := crowdSecParams()
-				p.ProcessLog = slog.New(slog.NewJSONHandler(&log, nil))
-				p.Alerts = queue
-				lists := start(t, e, p)
-				kept := lists.Snapshot()
-
-				e.set(tc.fail)
-
-				// Each failure is tried again a minute after it.
-				for range 2 {
-					time.Sleep(time.Minute)
-					synctest.Wait()
-				}
-
-				wantEngineFetches(t, e, 3)
-				wantDecision(
-					t,
-					lists,
-					suspect,
-					reputation.Decision{
-						Expires:  began.Add(4 * time.Hour),
-						Scenario: sshBF,
-					},
-				)
-
-				want := kept[0]
-				want.Tried = time.Now()
-
-				got := lists.Snapshot()
-				if !reflect.DeepEqual(got, []reputation.List{want}) {
-					t.Errorf(
-						"lists %+v, want the first copy, last tried now, %+v",
-						got,
-						want,
-					)
-				}
-
-				if n := lists.Failures(decisionsURL); n != 2 {
-					t.Errorf("%d failures, want 2", n)
-				}
-
-				// One alert for the first failure; the cooldown holds back the
-				// second.
-				failed := time.Now().Add(-time.Minute)
-				alert := fetchFailure(failed, decisionsURL, tc.error)
-				wantAlert(t, queue, alert)
-
-				if !strings.Contains(
-					log.String(),
-					`"msg":"fetching a list failed",`+
-						`"url":"`+decisionsURL+`","error":"`+tc.error,
-				) {
-					t.Errorf("logged\n%s\nwant the failures", log.String())
-				}
-
-				wantKeyNotShown(t, e, log.String(), lists, queue)
-			})
-		})
-	}
-}
-
-// crowdSecFailure is a way for the engine to fail: fail has it answer the
-// fetches after the first so that they fail with error.
-type crowdSecFailure struct {
-	name  string
-	fail  func(e *engine)
-	error string
-}
-
-// crowdSecFailures returns the ways the engine can fail.
-func crowdSecFailures() []crowdSecFailure {
-	const notDecision = " does not give an address or a netblock and a duration, " +
-		"such as 4h0m0s"
-
-	return []crowdSecFailure{
-		{
-			"an answer other than 200",
-			func(e *engine) { e.failing = true },
-			"the server answered 503 Service Unavailable",
-		},
-		{
-			"a key the engine refuses",
-			func(e *engine) { e.key = "another-key-0123456789abcdef" },
-			"the server answered 403 Forbidden",
-		},
-		{
-			"a redirect",
-			func(e *engine) { e.redirect = "http://elsewhere.example/v1/decisions" },
-			"the server answered 302 Found",
-		},
-		{
-			"an answer that does not read",
-			func(e *engine) { e.answer = "<html>" },
-			"read the answer: invalid character '<' looking for beginning of value",
-		},
-		{
-			"a decision to ban whose value does not read",
-			func(e *engine) {
-				e.answer = `[{"duration": "4h", "scenario": "` + sshBF + `", ` +
-					`"scope": "Ip", "type": "ban", "value": "203.0.113.300"}]`
-			},
-			"decision 1" + notDecision,
-		},
-		{
-			"a decision to ban whose duration does not read",
-			func(e *engine) {
-				e.answer = `[{"duration": "4h", "scope": "Country", "type": "ban", ` +
-					`"value": "KP"}, {"duration": "four hours", "scope": "Range", ` +
-					`"type": "ban", "value": "198.51.100.0/24"}]`
-			},
-			"decision 2" + notDecision,
-		},
-	}
-}
-
-// wantKeyNotShown checks that no fetch carried the engine's key to a URL
-// other than its decision list, such as the one a redirect names, and that
-// the key is in none of what the fetches leave behind: log, the process
-// log, the alerts waiting in queue, and the copies of lists, which
-// lists.json keeps.
-func wantKeyNotShown(
-	t *testing.T,
-	e *engine,
-	log string,
-	lists *reputation.Lists,
-	queue *alerts.Queue,
-) {
-	t.Helper()
-
-	e.mu.Lock()
-	keySentTo := e.keySentTo
-	e.mu.Unlock()
-
-	if len(keySentTo) != 0 {
-		t.Errorf("the key was sent to %v", keySentTo)
-	}
-
-	shown, err := json.Marshal([]any{lists.Snapshot(), waiting(queue)})
-	if err != nil {
-		t.Fatalf("encode: %v", err)
-	}
-
-	if strings.Contains(log+string(shown), engineKey) {
-		t.Errorf("the key is shown in\n%s\n%s", log, shown)
-	}
-}
-
-func TestCrowdSecDecisionListKeptAcrossARestartEndsWhenItsDecisionsDo(
-	t *testing.T,
-) {
-	t.Parallel()
-
-	synctest.Test(t, func(t *testing.T) {
-		began := time.Now()
-		e := &engine{key: engineKey, decisions: []decision{
-			{
-				rangeScope,
-				"198.51.100.0/24",
-				ban,
-				probing,
-				began.Add(time.Hour),
-			},
-		}}
-		lists := start(t, e, crowdSecParams())
-		kept := lists.Snapshot()
-
-		// Restarted half an hour later with what lists.json keeps, and
-		// the engine down, the decision still bans, until the end it had at
-		// the fetch, half an hour on.
-		time.Sleep(30 * time.Minute)
-
-		down := &engine{key: engineKey, failing: true}
-		again := reputation.New(crowdSecParams())
-		again.SetTransport(down)
-
-		err := again.Load(kept)
-		if err != nil {
-			t.Fatalf("load: %v", err)
-		}
-
-		run(t, again)
-
-		want := reputation.Decision{
-			Expires:  began.Add(time.Hour),
-			Scenario: probing,
-		}
-		wantDecision(t, again, "198.51.100.7", want)
-
-		time.Sleep(30*time.Minute - time.Nanosecond)
-		synctest.Wait()
-		wantDecision(t, again, "198.51.100.7", want)
-
-		time.Sleep(time.Nanosecond)
-		synctest.Wait()
-		wantDecision(t, again, "198.51.100.7", reputation.Decision{})
-	})
-}
-
-func TestLoadTakesACrowdSecListNeverFetchedAndRefusesACopyThatDoesNotRead(
-	t *testing.T,
-) {
-	t.Parallel()
-
-	now := time.Date(2026, 10, 6, 0, 0, 0, 0, time.UTC)
-	lists := reputation.New(crowdSecParams())
-
-	// Tried, and never fetched: there is no copy to read.
-	err := lists.Load([]reputation.List{{URL: decisionsURL, Tried: now}})
-	if err != nil {
-		t.Errorf("load the list never fetched: %v", err)
-	}
-
-	err = lists.Load([]reputation.List{{
-		URL: decisionsURL, Tried: now, Fetched: now, Lines: []string{
-			`[{"duration": "4h", "scope": "Range", "type": "ban", ` +
-				`"value": "198.51.100.0/33"}]`,
-		},
-	}})
-
-	const want = "the copy of " + decisionsURL + ": decision 1 does not give an " +
-		"address or a netblock and a duration, such as 4h0m0s"
-	if err == nil || err.Error() != want {
-		t.Errorf("error %v, want %s", err, want)
-	}
-}
-
-// engine is a stand-in for the local API of a CrowdSec engine. It answers
-// a fetch of the decision list that carries its key in X-Api-Key with its
-// decisions still in force, each with the time it has left as it answers,
-// by the bubble's clock, as an engine does, or with answer while that is
-// not "". It answers 403 to a fetch without its key, as an engine does,
-// with a redirect to redirect while that is not "", and 503 while failing.
-// It counts the fetches, and notes in keySentTo the URL of each fetch of
-// another URL that carries a key, as one following a redirect would.
-type engine struct {
-	mu        sync.Mutex
-	key       string
-	decisions []decision
-	answer    string
-	redirect  string
-	failing   bool
-	fetches   int
-	keySentTo []string
-}
-
-// decision is a decision of the engine, which ends at expires.
-type decision struct {
-	scope, value, kind, scenario string
-	expires                      time.Time
-}
-
-// RoundTrip has the engine answer req, in place of the network.
-func (e *engine) RoundTrip(req *http.Request) (*http.Response, error) {
-	e.mu.Lock()
-	defer e.mu.Unlock()
-
-	e.fetches++
-
-	if req.URL.String() != decisionsURL &&
-		req.Header.Get("X-Api-Key") != "" {
-		e.keySentTo = append(e.keySentTo, req.URL.String())
-	}
-
-	status, header, body := http.StatusOK, http.Header{}, e.answer
-
-	switch {
-	case req.URL.String() != decisionsURL || req.Header.Get("X-Api-Key") != e.key:
-		status, body = http.StatusForbidden, `{"message":"access forbidden"}`
-	case e.redirect != "":
-		status, header = http.StatusFound, http.Header{
-			"Location": {e.redirect},
-		}
-	case e.failing:
-		status, body = http.StatusServiceUnavailable, ""
-	case body == "":
-		body = e.inForce(time.Now())
-	}
-
-	return &http.Response{
-		StatusCode: status,
-		Status:     fmt.Sprintf("%d %s", status, http.StatusText(status)),
-		Header:     header,
-		Body:       io.NopCloser(strings.NewReader(body)),
-		Request:    req,
-	}, nil
-}
-
-// inForce returns the decisions in force at now, as the engine answers
-// them: a JSON list, null for none.
-func (e *engine) inForce(now time.Time) string {
-	var answer []map[string]string
-
-	for _, d := range e.decisions {
-		if now.Before(d.expires) {
-			answer = append(answer, map[string]string{
-				"duration": d.expires.Sub(now).
-					String(),
-				"origin":   "crowdsec",
-				"scenario": d.scenario, "scope": d.scope, "type": d.kind, "value": d.value,
-			})
-		}
-	}
-
-	body, err := json.Marshal(answer)
-	if err != nil {
-		panic(err) // a list of maps of strings always encodes
-	}
-
-	return string(body)
-}
-
-// set changes the engine with change.
-func (e *engine) set(change func(e *engine)) {
-	e.mu.Lock()
-	defer e.mu.Unlock()
-
-	change(e)
-}
-
-// crowdSecParams returns the Params of the decision list of the tests'
-// engine, fetched with its key, by the bubble's clock, with alerts to a
-// queue that sends none.
-func crowdSecParams() reputation.Params {
-	p := params()
-	p.CrowdSecDecisionsURL = decisionsURL
-	p.CrowdSecKey = engineKey
-
-	return p
-}
-
-// wantEngineFetches waits until Run has made the fetches due, and checks
-// how many the engine has had.
-func wantEngineFetches(t *testing.T, e *engine, want int) {
-	t.Helper()
-
-	synctest.Wait()
-
-	e.mu.Lock()
-	got := e.fetches
-	e.mu.Unlock()
-
-	if got != want {
-		t.Errorf("%d fetches, want %d", got, want)
-	}
-}
-
-// wantDecision checks the decision lists says is in force on addr now,
-// the zero Decision for none.
-func wantDecision(
-	t *testing.T,
-	lists *reputation.Lists,
-	addr string,
-	want reputation.Decision,
-) {
-	t.Helper()
-
-	got, listed := lists.CrowdSecDecision(
-		netip.MustParseAddr(addr),
-		time.Now(),
-	)
-	if listed != !want.Expires.IsZero() ||
-		listed &&
-			(!got.Expires.Equal(want.Expires) || got.Scenario != want.Scenario) {
-		t.Errorf(
-			"%s has the decision %+v in force %t, want %+v",
-			addr,
-			got,
-			listed,
-			want,
-		)
-	}
-}

internal/reputation/export_test.go

@@ -11,7 +11,6 @@ import (
 // network.
 func (l *Lists) SetTransport(transport http.RoundTripper) {
 	l.httpClient.Transport = transport
-	l.crowdSecClient.Transport = transport
 }
 
 // SetTransport has a's checks go through transport instead of the

internal/reputation/reputation.go

@@ -1,8 +1,7 @@
 // Package reputation fetches the lists the settings name by URL: the
 // blocklists of SWW_WAF_BLOCKLIST_URLS, the file of AS:percent lines
-// SWW_WAF_ASN_LIMIT_PERCENT_URL names, the address lists of SWW_WAF_TAG_LISTS, and
-// the decision list of the CrowdSec engine SWW_WAF_CROWDSEC_LAPI_URL names. It
-// keeps the last good copy of
+// SWW_WAF_ASN_LIMIT_PERCENT_URL names, and the address lists of
+// SWW_WAF_TAG_LISTS. It keeps the last good copy of
 // each, whole, comment lines included, which is used while a fetch fails,
 // and when each was last tried. It also asks the DNSBL zones of
 // SWW_WAF_DNSBL_ZONES about clients, and keeps their verdicts, and checks
@@ -13,7 +12,6 @@ package reputation
 
 import (
 	"context"
-	"encoding/json"
 	"errors"
 	"fmt"
 	"io"
@@ -35,10 +33,6 @@ const (
 	maxListBytes = 16 << 20
 	// fetchTimeout bounds one fetch of a list.
 	fetchTimeout = time.Minute
-	// crowdSecRefresh is how long after the CrowdSec decision list was last
-	// fetched or tried it is fetched again: the engine is the operator's
-	// own, and makes and ends decisions all the time.
-	crowdSecRefresh = time.Minute
 	// mappedBits is the length of ::ffff:0.0.0.0/96, the netblock of every
 	// IPv4-mapped address.
 	mappedBits = 96
@@ -52,9 +46,6 @@ var (
 	)
 	errNotASNPercent = errors.New(
 		"is not an AS number, : and a percentage, such as AS64496:50")
-	errNotDecision = errors.New(
-		"does not give an address or a netblock and a duration, such as 4h0m0s",
-	)
 )
 
 // List is a list as lists.json holds it: the URL it is fetched from,
@@ -77,14 +68,8 @@ type Params struct {
 	ASNLimitPercentURL string
 	// TagLists are the address lists that add a tag (SWW_WAF_TAG_LISTS).
 	TagLists []config.TagList
-	// CrowdSecDecisionsURL is the CrowdSec decision list, "" while
-	// SWW_WAF_CROWDSEC_LAPI_URL is unset, fetched with CrowdSecKey
-	// (SWW_WAF_CROWDSEC_LAPI_KEY).
-	CrowdSecDecisionsURL string
-	CrowdSecKey          string
 	// Refresh is how long after a list was last fetched or tried it is
-	// fetched again (SWW_WAF_BLOCKLIST_REFRESH), but for the CrowdSec decision
-	// list, which is fetched again crowdSecRefresh after.
+	// fetched again (SWW_WAF_BLOCKLIST_REFRESH).
 	Refresh time.Duration
 	// Now tells the time, normally time.Now in UTC.
 	Now func() time.Time
@@ -99,10 +84,6 @@ type Params struct {
 type Lists struct {
 	params     Params
 	httpClient *http.Client
-	// crowdSecClient fetches the CrowdSec decision list. It follows no
-	// redirect, so that the key goes to the engine alone: a redirect is a
-	// failure.
-	crowdSecClient *http.Client
 
 	mu sync.Mutex
 	// lists are by URL, one for each URL Params names.
@@ -119,22 +100,12 @@ type list struct {
 }
 
 // entries are what the lines of a copy say: for a blocklist or a tag list, the
-// netblocks it names, with the lengths among them, for the file of AS:percent
-// lines, the percentage it gives each AS number, and for the CrowdSec decision
-// list, the decision on each netblock that ends last, with the lengths among
-// them.
+// netblocks it names, with the lengths among them, and for the file of
+// AS:percent lines, the percentage it gives each AS number.
 type entries struct {
 	netblocks map[netip.Prefix]bool
 	lengths   []int
 	percents  map[string]int64
-	decisions map[netip.Prefix]Decision
-}
-
-// Decision is a decision of the CrowdSec engine to ban a netblock: when
-// it ends, and the scenario that made it, such as crowdsecurity/ssh-bf.
-type Decision struct {
-	Expires  time.Time
-	Scenario string
 }
 
 // New returns the lists, without a copy of any yet.
@@ -142,12 +113,7 @@ func New(params Params) *Lists {
 	l := &Lists{
 		params:     params,
 		httpClient: &http.Client{},
-		crowdSecClient: &http.Client{
-			CheckRedirect: func(*http.Request, []*http.Request) error {
-				return http.ErrUseLastResponse
-			},
-		},
-		lists: map[string]*list{},
+		lists:      map[string]*list{},
 	}
 
 	for _, listURL := range l.URLs() {
@@ -159,7 +125,7 @@ func New(params Params) *Lists {
 
 // URLs returns the URL of every list: the blocklists' in the order
 // SWW_WAF_BLOCKLIST_URLS names them, then SWW_WAF_ASN_LIMIT_PERCENT_URL, then the
-// tag lists', then the CrowdSec decision list's.
+// tag lists'.
 func (l *Lists) URLs() []string {
 	urls := slices.Clone(l.params.BlocklistURLs)
 	if l.params.ASNLimitPercentURL != "" {
@@ -170,10 +136,6 @@ func (l *Lists) URLs() []string {
 		urls = append(urls, list.URL)
 	}
 
-	if l.params.CrowdSecDecisionsURL != "" {
-		urls = append(urls, l.params.CrowdSecDecisionsURL)
-	}
-
 	return urls
 }
 
@@ -225,40 +187,6 @@ func (l *Lists) ASNLimitPercent(asn string) (int64, bool) {
 	return percent, listed
 }
 
-// CrowdSecDecision returns the decision of the copy of the CrowdSec
-// decision list on a netblock that holds addr and that ends last, and
-// whether it is still in force at now. A decision that has ended no
-// longer bans, even before the next fetch drops it.
-func (l *Lists) CrowdSecDecision(
-	addr netip.Addr,
-	now time.Time,
-) (Decision, bool) {
-	if l.params.CrowdSecDecisionsURL == "" {
-		return Decision{}, false
-	}
-
-	l.mu.Lock()
-	defer l.mu.Unlock()
-
-	kept := l.lists[l.params.CrowdSecDecisionsURL].entries
-
-	var last Decision
-
-	for _, length := range kept.lengths {
-		netblock, err := addr.Prefix(length)
-		if err != nil {
-			continue // an IPv6 netblock's length, past an IPv4 address's 32 bits
-		}
-
-		decision := kept.decisions[netblock]
-		if decision.Expires.After(last.Expires) {
-			last = decision
-		}
-	}
-
-	return last, now.Before(last.Expires)
-}
-
 // Fetched returns when the copy in use of the list at listURL was
 // fetched, or zero while there is none.
 func (l *Lists) Fetched(listURL string) time.Time {
@@ -331,7 +259,7 @@ func (l *Lists) Load(lists []List) error {
 			continue // dropped, or a list tried but never fetched, without a copy
 		}
 
-		read, err := l.parse(kept.URL, kept.Lines, kept.Fetched)
+		read, err := l.parse(kept.URL, kept.Lines)
 		if err != nil {
 			return fmt.Errorf("the copy of %s: %w", kept.URL, err)
 		}
@@ -377,8 +305,7 @@ func (l *Lists) fetchDue(ctx context.Context) time.Time {
 }
 
 // due returns when the list at listURL is to be fetched: Refresh after it
-// was last fetched or tried, the later of the two, or crowdSecRefresh
-// after for the CrowdSec decision list.
+// was last fetched or tried, the later of the two.
 func (l *Lists) due(listURL string) time.Time {
 	l.mu.Lock()
 	defer l.mu.Unlock()
@@ -390,10 +317,6 @@ func (l *Lists) due(listURL string) time.Time {
 		last = held.kept.Tried
 	}
 
-	if listURL == l.params.CrowdSecDecisionsURL {
-		return last.Add(crowdSecRefresh)
-	}
-
 	return last.Add(l.params.Refresh)
 }
 
@@ -408,7 +331,7 @@ func (l *Lists) fetch(ctx context.Context, listURL string) {
 
 	var found entries
 	if err == nil {
-		found, err = l.parse(listURL, lines, now)
+		found, err = l.parse(listURL, lines)
 	}
 
 	cutOff := err != nil && ctx.Err() != nil
@@ -468,11 +391,8 @@ func raiseFailure(queue *alerts.Queue, reason, source string, err error) {
 	})
 }
 
-// get fetches the list at listURL, and returns its lines. The CrowdSec
-// decision list is fetched with CrowdSecKey in the header X-Api-Key, where
-// the engine looks for it, by crowdSecClient, which follows no redirect.
-// An answer other than 200, or a list longer than maxListBytes, is a
-// failure.
+// get fetches the list at listURL, and returns its lines. An answer other
+// than 200, or a list longer than maxListBytes, is a failure.
 func (l *Lists) get(ctx context.Context, listURL string) ([]string, error) {
 	ctx, cancel := context.WithTimeout(ctx, fetchTimeout)
 	defer cancel()
@@ -487,14 +407,7 @@ func (l *Lists) get(ctx context.Context, listURL string) ([]string, error) {
 		return nil, fmt.Errorf("make the request: %w", err)
 	}
 
-	client := l.httpClient
-
-	if listURL == l.params.CrowdSecDecisionsURL {
-		req.Header.Set("X-Api-Key", l.params.CrowdSecKey)
-		client = l.crowdSecClient
-	}
-
-	res, err := client.Do(req)
+	res, err := l.httpClient.Do(req)
 	if err != nil {
 		// Do's error names the URL, which the log line and the alert name
 		// already: only what went wrong is kept.
@@ -526,22 +439,16 @@ func (l *Lists) get(ctx context.Context, listURL string) ([]string, error) {
 	return lines, nil
 }
 
-// parse reads the lines of the list at listURL, fetched at fetched: those
-// of a blocklist or a tag list, of the file of AS:percent lines, or of the
-// CrowdSec decision list. In all but the decision list, anything after a ; or
-// a # on a line is left out, and so is a line left blank. Any other line that
+// parse reads the lines of the list at listURL: those of a blocklist or a
+// tag list, or of the file of AS:percent lines. Anything after a ; or a #
+// on a line is left out, and so is a line left blank. Any other line that
 // does not read is an error naming it by its number.
-func (l *Lists) parse(
-	listURL string, lines []string, fetched time.Time,
-) (entries, error) {
-	switch listURL {
-	case l.params.ASNLimitPercentURL:
+func (l *Lists) parse(listURL string, lines []string) (entries, error) {
+	if listURL == l.params.ASNLimitPercentURL {
 		return parsePercents(lines)
-	case l.params.CrowdSecDecisionsURL:
-		return parseDecisions(lines, fetched)
-	default:
-		return parseNetblocks(lines)
 	}
+
+	return parseNetblocks(lines)
 }
 
 // parseNetblocks reads the lines of a blocklist or a tag list, each an address
@@ -628,64 +535,6 @@ func parsePercents(lines []string) (entries, error) {
 	return found, nil
 }
 
-// parseDecisions reads the lines of the CrowdSec decision list fetched at
-// fetched: the engine's answer, a JSON list of its decisions in force,
-// null while it has none. A decision of the type ban whose scope is Ip or
-// Range, as CrowdSec names them, bans its value, an address or a netblock
-// as parseNetblock reads it, until its duration, the time it had left as
-// the engine answered, has passed since fetched. Any other decision, such
-// as one to show a captcha or one on a country, is left out. A decision
-// to ban whose value or duration does not read is an error naming it by
-// its number.
-func parseDecisions(lines []string, fetched time.Time) (entries, error) {
-	var answer []struct {
-		Duration string `json:"duration"`
-		Scenario string `json:"scenario"`
-		Scope    string `json:"scope"`
-		Type     string `json:"type"`
-		Value    string `json:"value"`
-	}
-
-	err := json.Unmarshal([]byte(strings.Join(lines, "\n")), &answer)
-	if err != nil {
-		return entries{}, fmt.Errorf("read the answer: %w", err)
-	}
-
-	found := entries{decisions: map[netip.Prefix]Decision{}}
-
-	for i, decision := range answer {
-		if decision.Type != "ban" ||
-			(decision.Scope != "Ip" && decision.Scope != "Range") {
-			continue
-		}
-
-		netblock, ok := parseNetblock(decision.Value)
-
-		duration, err := time.ParseDuration(decision.Duration)
-		if !ok || err != nil {
-			return entries{}, fmt.Errorf(
-				"decision %d %w",
-				i+1,
-				errNotDecision,
-			)
-		}
-
-		expires := fetched.Add(duration)
-		if expires.After(found.decisions[netblock].Expires) {
-			found.decisions[netblock] = Decision{
-				Expires:  expires,
-				Scenario: decision.Scenario,
-			}
-		}
-
-		if !slices.Contains(found.lengths, netblock.Bits()) {
-			found.lengths = append(found.lengths, netblock.Bits())
-		}
-	}
-
-	return found, nil
-}
-
 // withoutComment returns line without anything after a ; or a #, and
 // without the spaces around what is left.
 func withoutComment(line string) string {

internal/requestlog/requestlog.go

@@ -21,7 +21,12 @@ const (
 	// the app.
 	ActionForward = "forward"
 
-	// ActionRequestHeaderTooLarge is a request over the header limits.
+	// ActionRequestLineTooLong is a request whose request line is too long for
+	// the header limits.
+	ActionRequestLineTooLong = "request_line_too_long"
+
+	// ActionRequestHeaderTooLarge is a request whose headers are over the
+	// header limits.
 	ActionRequestHeaderTooLarge = "request_header_too_large"
 
 	// ActionClientIsRateLimited is a request refused because it took its
@@ -29,9 +34,8 @@ const (
 	ActionClientIsRateLimited = "client_is_rate_limited"
 
 	// ActionTemporarilyBanned is a request refused because a ban that runs
-	// out covers its client, or because it matched a ban rule, asked for a
-	// trap path or the CrowdSec decision list lists its client, and so made
-	// such a ban.
+	// out covers its client, or because it matched a ban rule or asked for a
+	// trap path, and so made such a ban.
 	ActionTemporarilyBanned = "temporarily_banned"
 
 	// ActionPermanentlyBanned is a request refused because a ban that never
@@ -144,7 +148,7 @@ type Line struct {
 	// taken with a request it would have refused: ActionClientDenied,
 	// ActionTemporarilyBanned, ActionPermanentlyBanned, ActionCountryDenied,
 	// ActionClientIsRateLimited, ActionBlockedByBlockRule,
-	// ActionBlockedByCoreRuleSet, or, in waf,
+	// ActionBlockedByCoreRuleSet, or, in waf, ActionRequestLineTooLong or
 	// ActionRequestHeaderTooLarge for the header limits.
 	WouldAction string `json:"would_action,omitempty"`
 	// Heuristic is the name of the heuristic that refused the request, in
@@ -184,8 +188,7 @@ type Line struct {
 	// LimitHitMinuteRefusals for the refusal limit.
 	LimitHit string `json:"limit_hit,omitempty"`
 	// Reputation are the URLs of the blocklists that list the client, then
-	// that of the CrowdSec decision list when it does, then the DNSBL zones
-	// whose verdict lists it, their keys masked, then abuseipdb when its
+	// the DNSBL zones whose verdict lists it, their keys masked, then abuseipdb when its
 	// score is a hit.
 	Reputation []string `json:"reputation,omitempty"`
 	// Tags are the request's tags, sorted.

internal/rproxy/breaker.go

@@ -0,0 +1,82 @@
+package rproxy
+
+import (
+	"errors"
+	"sync"
+	"time"
+)
+
+// What opens the circuit breaker, and how often a request asks waf while it is
+// open.
+const (
+	breakerFailures    = 5
+	breakerWindow      = 5 * time.Second
+	breakerAskInterval = time.Second
+)
+
+// errBreakerOpen is why a request did not ask waf.
+var errBreakerOpen = errors.New(
+	"waf is not asked while the circuit breaker is open",
+)
+
+// breaker is the circuit breaker for asks to waf. It opens when
+// breakerFailures asks fail within breakerWindow. An ask fails when it gets no
+// answer in time, or an answer rproxy cannot pass on. While it is open, at
+// most one request each breakerAskInterval asks waf. Any usable answer closes
+// it, whatever it decides, and forgets the failures before it.
+type breaker struct {
+	mu sync.Mutex
+	// failures holds the times of the latest failed asks, oldest first, at most
+	// breakerFailures of them.
+	failures []time.Time
+	open     bool
+	// lastAsk is when a request last asked waf while the breaker was open.
+	lastAsk time.Time
+}
+
+// mayAsk reports whether a request may ask waf at now. While the breaker is
+// open, it says yes once each breakerAskInterval.
+func (b *breaker) mayAsk(now time.Time) bool {
+	b.mu.Lock()
+	defer b.mu.Unlock()
+
+	if !b.open {
+		return true
+	}
+
+	if now.Sub(b.lastAsk) < breakerAskInterval {
+		return false
+	}
+
+	b.lastAsk = now
+
+	return true
+}
+
+// noteAnswer notes that an ask got an answer rproxy can use. It closes the
+// breaker and forgets the failures before it.
+func (b *breaker) noteAnswer() {
+	b.mu.Lock()
+	defer b.mu.Unlock()
+
+	b.open = false
+	b.failures = nil
+}
+
+// noteFailure notes that an ask that ended at now got no answer in time, and
+// opens the breaker if breakerFailures asks have failed within breakerWindow.
+func (b *breaker) noteFailure(now time.Time) {
+	b.mu.Lock()
+	defer b.mu.Unlock()
+
+	b.failures = append(b.failures, now)
+	if len(b.failures) > breakerFailures {
+		b.failures = b.failures[1:]
+	}
+
+	if !b.open && len(b.failures) == breakerFailures &&
+		now.Sub(b.failures[0]) <= breakerWindow {
+		b.open = true
+		b.lastAsk = now
+	}
+}

internal/rproxy/breaker_test.go

@@ -0,0 +1,142 @@
+package rproxy_test
+
+import (
+	"testing"
+	"time"
+
+	"sneak.berlin/go/smallwebwaf/internal/rproxy"
+)
+
+// The breaker tests give the breaker each time themselves, counted from
+// time.Now(), and never wait.
+
+// fail notes count failed asks on b, one each step from at.
+func fail(b *rproxy.Breaker, at time.Time, count int, step time.Duration) {
+	for i := range count {
+		b.NoteFailure(at.Add(time.Duration(i) * step))
+	}
+}
+
+// openBreaker returns a breaker opened at now by five failed asks, one a
+// second.
+func openBreaker(now time.Time) *rproxy.Breaker {
+	b := &rproxy.Breaker{}
+	fail(b, now.Add(-4*time.Second), 5, time.Second)
+
+	return b
+}
+
+func TestFourFailedAsksWithinFiveSecondsLeaveTheBreakerClosed(t *testing.T) {
+	t.Parallel()
+
+	now := time.Now()
+	b := &rproxy.Breaker{}
+	fail(b, now, 4, time.Second)
+
+	if !b.MayAsk(now.Add(3 * time.Second)) {
+		t.Error("a request may not ask, want it to")
+	}
+}
+
+func TestFiveFailedAsksWithinFiveSecondsOpenTheBreaker(t *testing.T) {
+	t.Parallel()
+
+	now := time.Now()
+	b := openBreaker(now)
+
+	if b.MayAsk(now) {
+		t.Error("a request may ask, want it not to")
+	}
+}
+
+func TestFiveFailedAsksOverMoreThanFiveSecondsLeaveTheBreakerClosed(
+	t *testing.T,
+) {
+	t.Parallel()
+
+	now := time.Now()
+	b := &rproxy.Breaker{}
+	fail(b, now, 5, 1300*time.Millisecond)
+
+	if !b.MayAsk(now.Add(6 * time.Second)) {
+		t.Error("a request may not ask, want it to")
+	}
+}
+
+func TestAnAnswerBetweenFailedAsksKeepsTheBreakerClosed(t *testing.T) {
+	t.Parallel()
+
+	now := time.Now()
+	b := &rproxy.Breaker{}
+	fail(b, now, 4, 100*time.Millisecond)
+	b.NoteAnswer()
+	fail(b, now.Add(500*time.Millisecond), 4, 100*time.Millisecond)
+
+	if !b.MayAsk(now.Add(900 * time.Millisecond)) {
+		t.Error("a request may not ask, want it to")
+	}
+}
+
+func TestAnOpenBreakerLetsOneRequestAskEachSecond(t *testing.T) {
+	t.Parallel()
+
+	now := time.Now()
+	b := openBreaker(now)
+
+	for _, tc := range []struct {
+		after time.Duration
+		want  bool
+	}{
+		{999 * time.Millisecond, false},
+		{time.Second, true},
+		{time.Second, false},
+		{1500 * time.Millisecond, false},
+		{2 * time.Second, true},
+	} {
+		got := b.MayAsk(now.Add(tc.after))
+		if got != tc.want {
+			t.Errorf("may ask %v after it opened: %v, want %v",
+				tc.after, got, tc.want)
+		}
+	}
+}
+
+func TestAFailedAskKeepsTheBreakerOpen(t *testing.T) {
+	t.Parallel()
+
+	opened := time.Now()
+	b := openBreaker(opened)
+	now := opened.Add(time.Second)
+	b.MayAsk(now)
+	b.NoteFailure(now)
+
+	if b.MayAsk(now.Add(999 * time.Millisecond)) {
+		t.Error("a request may ask, want it not to")
+	}
+
+	if !b.MayAsk(now.Add(time.Second)) {
+		t.Error("a request may not ask a second later, want it to")
+	}
+}
+
+func TestOneAnswerClosesTheBreaker(t *testing.T) {
+	t.Parallel()
+
+	opened := time.Now()
+	b := openBreaker(opened)
+	now := opened.Add(time.Second)
+	b.MayAsk(now)
+	b.NoteAnswer()
+
+	if !b.MayAsk(now) {
+		t.Error("a request may not ask, want it to")
+	}
+
+	// The failures before the answer no longer count, so one more does not open
+	// the breaker again.
+	b.NoteFailure(now)
+
+	if !b.MayAsk(now) {
+		t.Error("a request may not ask after one failure, want it to")
+	}
+}

internal/rproxy/export_test.go

@@ -0,0 +1,23 @@
+package rproxy
+
+import "time"
+
+// Breaker is the circuit breaker, for tests that give it the time.
+type Breaker struct {
+	b breaker
+}
+
+// MayAsk reports whether a request may ask waf at now.
+func (b *Breaker) MayAsk(now time.Time) bool {
+	return b.b.mayAsk(now)
+}
+
+// NoteAnswer notes that an ask got an answer rproxy can use.
+func (b *Breaker) NoteAnswer() {
+	b.b.noteAnswer()
+}
+
+// NoteFailure notes that an ask that ended at now got no answer in time.
+func (b *Breaker) NoteFailure(now time.Time) {
+	b.b.noteFailure(now)
+}

internal/rproxy/rproxy.go

@@ -4,10 +4,11 @@
 // waf goes to the visitor as waf gave it.
 // SWW_RPROXY_WAF_BACKEND_NO_ANSWER_DISPOSITION decides only when waf cannot
 // be connected to, does not answer at all, or does not answer within
-// SWW_RPROXY_WAF_BACKEND_TIMEOUT_MS. rproxy itself refuses a request with a
-// method it does not pass on, or one it cannot put to waf as the visitor
-// sent it. It keeps nothing between requests and writes nothing to disk. "rproxy" in
-// SPEC.md says what it does.
+// SWW_RPROXY_WAF_BACKEND_TIMEOUT_MS, or while the circuit breaker for asks to
+// waf is open. rproxy itself refuses a request with a method it does not pass
+// on, or one it cannot put to waf as the visitor sent it. It keeps nothing
+// between requests but the circuit breaker, and writes nothing to disk.
+// "rproxy" in SPEC.md says what it does.
 package rproxy
 
 import (
@@ -132,6 +133,8 @@ type handler struct {
 	wafTransport http.RoundTripper
 	// reportURL is where the reports go.
 	reportURL string
+	// breaker is the circuit breaker for asks to waf.
+	breaker breaker
 	// reports waits for the reports being sent. reportsMu guards starting one
 	// against reportsStopped, which is set once nothing is to wait for another.
 	reports        sync.WaitGroup
@@ -196,7 +199,7 @@ func (h *handler) ServeHTTP(w http.ResponseWriter, r *http.Request) {
 		return
 	}
 
-	answer, err := rq.ask(r.Context())
+	answer, err := rq.askUnlessBreakerOpen(r.Context())
 	if err != nil {
 		rq.handleNoUsableAnswer(r.Context(), err)
 

internal/rproxy/rproxy_test.go

@@ -15,6 +15,7 @@ import (
 	"strconv"
 	"strings"
 	"sync"
+	"sync/atomic"
 	"testing"
 	"time"
 
@@ -1395,6 +1396,139 @@ func TestSendsNoReportWithoutAnAnswer(t *testing.T) {
 	standIn.wantNoReport(t)
 }
 
+func TestFiveFailedAsksKeepTheNextRequestFromAskingWAF(t *testing.T) {
+	t.Parallel()
+
+	for name, failure := range map[string]http.HandlerFunc{
+		"no answer at all": func(http.ResponseWriter, *http.Request) {
+			panic(http.ErrAbortHandler)
+		},
+		"a slow answer": func(_ http.ResponseWriter, r *http.Request) {
+			<-r.Context().Done()
+		},
+	} {
+		t.Run(name, func(t *testing.T) {
+			t.Parallel()
+
+			var answering atomic.Bool
+
+			standIn := startWAF(
+				t,
+				func(w http.ResponseWriter, r *http.Request) {
+					if answering.Load() {
+						allow(w, r)
+
+						return
+					}
+
+					failure(w, r)
+				},
+			)
+			app := startApp(t, greet)
+			addr, out := startRProxy(
+				t,
+				standIn.URL,
+				app.URL,
+				map[string]string{
+					wafBackendTimeout: "200",
+				},
+			)
+
+			for range 5 {
+				wantGreeting(t, get(t, addr, "/"))
+				standIn.question(t)
+			}
+
+			answering.Store(true)
+			wantGreeting(t, get(t, addr, "/"))
+			out.waitFor(t, "the circuit breaker is open")
+
+			select {
+			case <-standIn.questions:
+				t.Error("waf was asked, want it not to be")
+			case <-time.After(10 * pollInterval):
+			}
+		})
+	}
+}
+
+func TestVisitorsThatGoAwayWhileWAFIsAskedLeaveTheBreakerClosed(
+	t *testing.T,
+) {
+	t.Parallel()
+
+	var answering atomic.Bool
+
+	standIn := startWAF(t, func(w http.ResponseWriter, r *http.Request) {
+		if answering.Load() {
+			allow(w, r)
+
+			return
+		}
+
+		<-r.Context().Done()
+	})
+	app := startApp(t, greet)
+	addr, out := startRProxy(t, standIn.URL, app.URL, map[string]string{
+		wafBackendTimeout: "60000",
+	})
+
+	// Five of these would open the breaker if they counted as failures.
+	for range 5 {
+		conn := dial(t, addr)
+		send(t, conn, "GET / HTTP/1.1\r\nHost: site.example\r\n\r\n")
+		id := standIn.question(t).header.Get(requestIDHeader)
+
+		_ = conn.Close()
+
+		// rproxy writes the request's log line once it is done with the ask.
+		out.waitFor(t, id)
+	}
+
+	answering.Store(true)
+	wantGreeting(t, get(t, addr, "/"))
+	standIn.question(t)
+}
+
+func TestAnswersThatCannotBePassedOnOpenTheBreaker(t *testing.T) {
+	t.Parallel()
+
+	var answering atomic.Bool
+
+	tooLarge := overOneMiB(dispositionDeny)
+	standIn := startWAF(t, func(w http.ResponseWriter, r *http.Request) {
+		if answering.Load() {
+			allow(w, r)
+
+			return
+		}
+
+		tooLarge(w, r)
+	})
+	app := startApp(t, greet)
+	addr, out := startRProxy(t, standIn.URL, app.URL, map[string]string{
+		wafBackendTimeout: "60000",
+	})
+
+	for range 5 {
+		if got := get(t, addr, "/"); got.status != http.StatusBadGateway {
+			t.Errorf("answered %d, want 502", got.status)
+		}
+
+		standIn.question(t)
+	}
+
+	answering.Store(true)
+	wantGreeting(t, get(t, addr, "/"))
+	out.waitFor(t, "the circuit breaker is open")
+
+	select {
+	case <-standIn.questions:
+		t.Error("waf was asked, want it not to be")
+	case <-time.After(10 * pollInterval):
+	}
+}
+
 func TestAPathUnderOwnPrefixNeverReachesTheApp(t *testing.T) {
 	t.Parallel()
 

internal/rproxy/waf.go

@@ -10,6 +10,7 @@ import (
 	"maps"
 	"net/http"
 	"strings"
+	"time"
 
 	"sneak.berlin/go/smallwebwaf/internal/waf"
 )
@@ -67,7 +68,8 @@ func (rq *request) handleNoUsableAnswer(ctx context.Context, err error) {
 		rq.answer(http.StatusBadGateway)
 	default:
 		// waf cannot be connected to, does not answer at all, or does not answer
-		// within SWW_RPROXY_WAF_BACKEND_TIMEOUT_MS. A request that keeps waf
+		// within SWW_RPROXY_WAF_BACKEND_TIMEOUT_MS; or the circuit breaker
+		// kept the request from asking. A request that keeps waf
 		// busy past SWW_RPROXY_WAF_BACKEND_TIMEOUT_MS, like any request while
 		// waf is overloaded, gets SWW_RPROXY_WAF_BACKEND_NO_ANSWER_DISPOSITION
 		// here. deny closes this, at the cost of answering 503 whenever waf is
@@ -86,6 +88,31 @@ func (rq *request) handleNoUsableAnswer(ctx context.Context, err error) {
 	}
 }
 
+// askUnlessBreakerOpen asks waf, unless the circuit breaker is open and it is
+// not yet time for a request to ask. It then tells the breaker whether waf
+// answered in time. An answer rproxy cannot pass on counts as a failure. A
+// visitor that goes away tells the breaker nothing. ctx is the request's own
+// context.
+func (rq *request) askUnlessBreakerOpen(
+	ctx context.Context,
+) (*wafAnswer, error) {
+	b := &rq.h.breaker
+	if !b.mayAsk(time.Now()) {
+		return nil, errBreakerOpen
+	}
+
+	answer, err := rq.ask(ctx)
+
+	switch {
+	case err == nil:
+		b.noteAnswer()
+	case ctx.Err() == nil:
+		b.noteFailure(time.Now())
+	}
+
+	return answer, err
+}
+
 // ask sends waf the question, and returns its answer, which must have come
 // whole within SWW_RPROXY_WAF_BACKEND_TIMEOUT_MS. It ends when ctx does, as
 // when the visitor goes away.

internal/state/state.go

@@ -104,7 +104,7 @@ var (
 	errVersion = errors.New("unknown version")
 	// errMissing is for an entry without a field it needs.
 	errMissing     = errors.New("has no")
-	errCause       = errors.New("is not limit, attack, admin or crowdsec")
+	errCause       = errors.New("is not limit, attack or admin")
 	errExpires     = errors.New("is not after its start")
 	errDestination = errors.New("is not webhook, slack or ntfy")
 	errScope       = errors.New(
@@ -967,7 +967,7 @@ func (e BanEntry) ban() bans.Ban {
 // each expires is read again as written. An expires not after the start
 // is refused too, since the netblock's next ban for a broken limit, three
 // times as long as this one, would then refuse nothing; and so is a cause
-// other than limit, attack, admin or crowdsec, most likely misspelt.
+// other than limit, attack or admin, most likely misspelt.
 func (f *bansFile) check(data []byte) error {
 	var written struct {
 		Bans []struct {
@@ -991,8 +991,7 @@ func (f *bansFile) check(data []byte) error {
 		case entry.Expires != nil && !entry.Expires.After(entry.Start):
 			return fmt.Errorf("entry %d's expires %w", i+1, errExpires)
 		case entry.Cause != "" && entry.Cause != bans.CauseLimit &&
-			entry.Cause != bans.CauseAttack && entry.Cause != bans.CauseAdmin &&
-			entry.Cause != bans.CauseCrowdSec:
+			entry.Cause != bans.CauseAttack && entry.Cause != bans.CauseAdmin:
 			return fmt.Errorf(
 				"entry %d's cause %q %w",
 				i+1,

internal/state/state_test.go

@@ -114,8 +114,7 @@ const permanentBansJSON = `{
                 "earlier_bans": {
                     "limit": 3,
                     "attack": 1,
-                    "admin": 1,
-                    "crowdsec": 2
+                    "admin": 1
                 }
             }
         }
@@ -1188,10 +1187,10 @@ func TestBanWithAnotherCauseStopsTheStart(t *testing.T) {
 		`{"netblock": "203.0.113.10/32", "start": "2026-10-06T00:00:00Z", `+
 		`"expires": null, "cause": "admin"}, `+
 		`{"netblock": "203.0.113.11/32", "start": "2026-10-06T00:00:00Z", `+
-		`"expires": "2026-10-06T04:00:00Z", "cause": "crowdsec"}, `+
+		`"expires": "2026-10-06T04:00:00Z", "cause": "limit"}, `+
 		`{"netblock": "203.0.113.12/32", "start": "2026-10-06T00:00:00Z", `+
 		`"expires": null, "cause": "atack"}]}`,
-		`: entry 4's cause "atack" is not limit, attack, admin or crowdsec`)
+		`: entry 4's cause "atack" is not limit, attack or admin`)
 }
 
 func TestBanThatDoesNotEndAfterItsStartStopsTheStart(t *testing.T) {
@@ -2466,9 +2465,8 @@ func office() netip.Prefix {
 	return netip.MustParsePrefix("203.0.113.0/24")
 }
 
-// fill puts a permanent ban an admin made, a ban for a broken limit, one
-// for a clear sign of attack and one for CrowdSec's decision, clients
-// with counts and histories,
+// fill puts a permanent ban an admin made, a ban for a broken limit and one
+// for a clear sign of attack, clients with counts and histories,
 // GeoJS answers, the blocklists' last tries and the copy of one, two
 // verdicts of a DNSBL zone, the AbuseIPDB checks spent today with two
 // scores, and two answers of routewatch, as filledListsJSON,
@@ -2485,13 +2483,6 @@ func fill(params state.Params) {
 	})
 	params.Ledger.BanForAttack(netip.MustParsePrefix("192.0.2.1/32"), now,
 		bans.Notes{RuleID: "env-file", Target: "path"})
-	params.Ledger.BanForCrowdSec(
-		netip.MustParsePrefix("198.51.100.9/32"),
-		now,
-		now.Add(4*time.Hour),
-		"crowdsecurity/ssh-bf",
-		bans.Notes{},
-	)
 
 	for _, c := range []string{"2001:db8::/64", "203.0.113.9/32", "192.0.2.1/32"} {
 		params.Limiter.Count(netip.MustParsePrefix(c), now, whole)
@@ -2634,10 +2625,9 @@ func permanentBan() bans.Ban {
 			Requests: 1500,
 			Refused:  3,
 			EarlierBans: bans.EarlierBans{
-				Limit:    3,
-				Attack:   1,
-				Admin:    1,
-				CrowdSec: 2,
+				Limit:  3,
+				Attack: 1,
+				Admin:  1,
 			},
 		},
 	}

internal/sww/rproxy_test.go

@@ -260,7 +260,17 @@ func TestTheSiteAnswersWhileWAFIsStoppedAndStartedAgain(t *testing.T) {
 		stop()
 	}()
 
-	wantStatus(t, site+"/", placed, http.StatusForbidden)
+	// The visitor's asks have opened rproxy's circuit breaker, which lets one
+	// request a second ask until one is answered.
+	deadline := time.Now().Add(waitLimit)
+	for statusFrom(t, site+"/", placed) != http.StatusForbidden {
+		if time.Now().After(deadline) {
+			t.Fatalf("request from %s: never answered %d", placed,
+				http.StatusForbidden)
+		}
+
+		time.Sleep(pollInterval)
+	}
 
 	close(visitorStop)
 	<-visitorDone

internal/sww/sww_test.go

@@ -847,92 +847,6 @@ func TestBlocklistTriesAndCopiesKeptInListsJSONAcrossRestarts(t *testing.T) {
 	}
 }
 
-func TestCrowdSecDecisionListKeptInListsJSONAcrossARestart(t *testing.T) {
-	t.Parallel()
-
-	const bouncerKey = "crowdsec-key-0123456789abcdef"
-
-	// A stand-in for the engine's local API, which bans 203.0.113.0/24 for
-	// four hours, and answers only a request with its key, while it is up.
-	down := new(atomic.Bool)
-	engine := httptest.NewServer(http.HandlerFunc(
-		func(w http.ResponseWriter, r *http.Request) {
-			switch {
-			case r.URL.Path != "/v1/decisions" || r.Header.Get("X-Api-Key") != bouncerKey:
-				w.WriteHeader(http.StatusForbidden)
-			case down.Load():
-				w.WriteHeader(http.StatusServiceUnavailable)
-			default:
-				_, _ = io.WriteString(
-					w,
-					`[{"duration": "4h0m0s", "origin": "crowdsec", `+
-						`"scenario": "crowdsecurity/http-probing", "scope": "Range", `+
-						`"type": "ban", "value": "203.0.113.0/24"}]`,
-				)
-			}
-		}))
-	t.Cleanup(engine.Close)
-
-	dir, cache := t.TempDir(), t.TempDir()
-	env := map[string]string{
-		listenAddr:                  localhost + ":0",
-		stateDir:                    dir,
-		cacheDir:                    cache,
-		ruleFilesDir:                t.TempDir(),
-		"SWW_WAF_CROWDSEC_LAPI_URL": engine.URL,
-		"SWW_WAF_CROWDSEC_LAPI_KEY": bouncerKey,
-	}
-
-	// Once the list is fetched, the client's request bans it.
-	first := runUntilStopped(t, env, func(url string) {
-		for statusFrom(t, url, placed) != http.StatusForbidden {
-			time.Sleep(pollInterval)
-		}
-	})
-
-	ban := onlyBan(t, dir)
-	if ban["netblock"] != placed+"/32" || ban["cause"] != "crowdsec" ||
-		ban["reason"] != "CrowdSec's decision for crowdsecurity/http-probing" {
-		t.Errorf(
-			"bans.json holds %v, want the ban for crowdsec on %s",
-			ban,
-			placed,
-		)
-	}
-
-	// Restarted with the engine down, the copy kept in lists.json bans
-	// another client in the netblock from its first request.
-	down.Store(true)
-
-	second := runUntilStopped(t, env, func(url string) {
-		wantStatus(t, url, "203.0.113.10", http.StatusForbidden)
-	})
-
-	// The key is in neither run's output, nor in a state or cache file.
-	files := []string{
-		filepath.Join(dir, "bans.json"), filepath.Join(dir, "clients.json"),
-		filepath.Join(cache, "lists.json"),
-	}
-	shown := make([]string, 0, len(files)+2)
-	shown = append(shown, first.text(), second.text())
-
-	for _, path := range files {
-		data, err := os.ReadFile(path) //nolint:gosec // the test's
-		if err != nil {
-			t.Fatalf("read %s: %v", path, err)
-		}
-
-		shown = append(shown, string(data))
-	}
-
-	if all := strings.Join(shown, "\n"); strings.Contains(all, bouncerKey) {
-		t.Errorf(
-			"the key is shown in the output or the state and cache files:\n%s",
-			all,
-		)
-	}
-}
-
 // wantDeniedByList checks that the request log line is of a request the
 // blocklist at listURL refused.
 func wantDeniedByList(t *testing.T, line map[string]any, listURL string) {

internal/waf/anomaly_test.go

@@ -349,6 +349,7 @@ func TestRequestCountsForTheASNumberGeoJSGivesBeforeItEnds(t *testing.T) {
 		map[string]string{
 			trustedProxies:                 trustLocalhost,
 			asnAndCountryLookupTimeout:     "3600000",
+			addLookupHeaders:               falseValue,
 			anomalyASN + requestsPerMinute: aLot,
 		})
 	server.Store(started)

internal/waf/answertime_test.go

@@ -39,6 +39,7 @@ const (
 	// The header limits SPEC.md gives.
 	cookieLimit      = 50
 	headerFieldLimit = 100
+	lineLimit        = 8192
 	// cookieHeader is the header the cookie limit counts.
 	cookieHeader = "Cookie"
 	// tooLarge is how waf refuses a request over the header limits.
@@ -48,9 +49,6 @@ const (
 	silentAbuseIPDBURL = "silent://abuseipdb/api/v2/check"
 	// wholeLimit is the percentage of a rate limit that lowers it not at all.
 	wholeLimit = 100
-	// clientsDecision is the CrowdSec decision list holding client alone.
-	clientsDecision = `[{"duration": "4h0m0s", "scenario": "crowdsecurity/ssh-bf", ` +
-		`"scope": "Ip", "type": "ban", "value": "` + client + `"}]`
 )
 
 // cookies returns a Cookie header's value with count cookies.
@@ -107,11 +105,139 @@ func TestHeaderLimitRefusalNamesItsHeuristicCountsAndLimits(t *testing.T) {
 	fillHeaders(req, headerFieldLimit+1)
 	do(t, req)
 
+	// The longest header line is X-Request-ID's, with its 26-character id.
 	wantHeuristic(
 		t,
 		s.out.requestLine(t),
 		"header_limits",
-		`{"fields": 101, "fields_limit": 100, "cookies": 0, "cookies_limit": 50}`,
+		`{"longest_header_line_bytes": 40, "header_line_bytes_limit": 8192,
+		"fields": 101, "fields_limit": 100, "cookies": 0, "cookies_limit": 50}`,
+	)
+}
+
+// longQuery returns a path whose request line, sent by Go's client as
+// "GET <path> HTTP/1.1", is lineBytes long.
+func longQuery(lineBytes int) string {
+	const around = len("GET /?q= HTTP/1.1")
+
+	return "/?q=" + strings.Repeat("a", lineBytes-around)
+}
+
+func TestARequestLineOverTheLimitIsRefusedWith414BeforeAnyOtherCheck(
+	t *testing.T,
+) {
+	t.Parallel()
+
+	for _, tc := range []struct {
+		name      string
+		lineBytes int
+		// cookies is how many cookies the request carries.
+		cookies int
+		status  int
+		action  string
+	}{
+		{
+			"at the limit", lineLimit, 0, http.StatusOK,
+			requestlog.ActionForward,
+		},
+		{
+			"over the limit", lineLimit + 1, 0, http.StatusRequestURITooLong,
+			requestlog.ActionRequestLineTooLong,
+		},
+		{
+			"over the limit and the cookie limit", lineLimit + 1,
+			cookieLimit + 1, http.StatusRequestURITooLong,
+			requestlog.ActionRequestLineTooLong,
+		},
+	} {
+		t.Run(tc.name, func(t *testing.T) {
+			t.Parallel()
+
+			s := startWAF(t, "", map[string]string{coreRuleSetMode: block})
+			req := s.question(siteA, client, longQuery(tc.lineBytes))
+
+			if tc.cookies > 0 {
+				req.Header.Set(cookieHeader, cookies(tc.cookies))
+			}
+
+			got := do(t, req)
+			line := s.out.requestLine(t)
+
+			if tc.status == http.StatusOK {
+				wantDisposition(t, got, tc.status, waf.DispositionAllow)
+			} else {
+				wantDisposition(t, got, tc.status, waf.DispositionDeny)
+			}
+
+			wantLine(t, line, tc.status, tc.action)
+
+			refused := tc.status != http.StatusOK
+			if refused != (line.DurationCoreRuleSetMS == nil) {
+				t.Errorf(
+					"Core Rule Set time %v for a request refused: %t",
+					line.DurationCoreRuleSetMS,
+					refused,
+				)
+			}
+		})
+	}
+}
+
+func TestAHeaderLineOverTheLimitIsRefusedWith431(t *testing.T) {
+	t.Parallel()
+
+	for _, tc := range []struct {
+		name string
+		make func(*http.Request)
+		// refused is true for a request over the limit, and false for one at it.
+		refused bool
+	}{
+		{"a header line at the limit", func(req *http.Request) {
+			req.Header.Set("X-Long", strings.Repeat("a", lineLimit-len("X-Long: ")))
+		}, false},
+		{"a header line over the limit", func(req *http.Request) {
+			req.Header.Set("X-Long", strings.Repeat("a", lineLimit+1-len("X-Long: ")))
+		}, true},
+		{"one cookie over the limit", func(req *http.Request) {
+			req.Header.Set(cookieHeader, "a="+strings.Repeat("a", lineLimit))
+		}, true},
+		{"a Host line over the limit", func(req *http.Request) {
+			req.Host = strings.Repeat("a", lineLimit+1-len("Host: "))
+		}, true},
+		{"a header sent twice, each line within the limit", func(req *http.Request) {
+			req.Header.Add("X-Long", strings.Repeat("a", 8000))
+			req.Header.Add("X-Long", strings.Repeat("a", 8000))
+		}, false},
+	} {
+		t.Run(tc.name, func(t *testing.T) {
+			t.Parallel()
+
+			s := startWAF(t, "", nil)
+			req := s.question(siteA, client, "/")
+			tc.make(req)
+
+			got := do(t, req)
+
+			if tc.refused {
+				wantDisposition(t, got, tooLarge, waf.DispositionDeny)
+			} else {
+				wantDisposition(t, got, http.StatusOK, waf.DispositionAllow)
+			}
+		})
+	}
+}
+
+func TestRequestLineRefusalNamesItsHeuristicLengthAndLimit(t *testing.T) {
+	t.Parallel()
+
+	s := startWAF(t, "", nil)
+	do(t, s.question(siteA, client, longQuery(lineLimit+1)))
+
+	wantHeuristic(
+		t,
+		s.out.requestLine(t),
+		"header_limits",
+		`{"request_line_bytes": 8193, "request_line_bytes_limit": 8192}`,
 	)
 }
 
@@ -296,10 +422,6 @@ func TestTheHeaderLimitsComeBeforeEveryCheckThatRefuses(t *testing.T) {
 			"/", leaveAsItIs,
 		},
 		{"a blocklist", map[string]string{blocklistURLs: dropURL}, "/", listClient},
-		{
-			"the CrowdSec decision list",
-			map[string]string{crowdSecURL: lapi, crowdSecKey: bouncerKey}, "/", decideOnClient,
-		},
 		{
 			"a DNS blocklist", map[string]string{
 				dnsblZones: dnsblZone, dnsblResolver: noResolver, dnsblAbuseIPDBAction: actionDeny,
@@ -592,12 +714,6 @@ func listClient(t *testing.T, server *waf.Server, now time.Time) {
 	}
 }
 
-// decideOnClient puts client on the CrowdSec decision list.
-func decideOnClient(t *testing.T, server *waf.Server, now time.Time) {
-	t.Helper()
-	loadDecisions(t, server, now, clientsDecision)
-}
-
 // leaveAsItIs prepares nothing.
 func leaveAsItIs(*testing.T, *waf.Server, time.Time) {}
 
@@ -641,12 +757,6 @@ func TestARefusedRequestDoesNotWaitForASlowGeoJS(t *testing.T) {
 			name: "a blocklist", env: map[string]string{blocklistURLs: dropURL},
 			prepare: listClient, status: forbidden, action: requestlog.ActionClientDenied,
 		},
-		{
-			name:    "the CrowdSec decision list",
-			env:     map[string]string{crowdSecURL: lapi, crowdSecKey: bouncerKey},
-			prepare: decideOnClient, status: forbidden,
-			action: requestlog.ActionTemporarilyBanned,
-		},
 		{
 			name: "the header limits", cookie: cookies(cookieLimit + 1),
 			prepare: leaveAsItIs, status: tooLarge,
@@ -774,7 +884,6 @@ func TestWAFAnswersWithinTheTimeLimitWhileEveryOutsideSourceHangs(
 		dnsblZones: dnsblZone, dnsblResolver: resolver,
 		abuseIPDBKey:  accountKey,
 		blocklistURLs: held + "/drop.txt", asnLimitPercentURL: held + "/asn.txt",
-		crowdSecURL: held, crowdSecKey: bouncerKey,
 	})
 
 	// The lists are fetched outside the synctest bubble below: a wait on the

internal/waf/bans.go

@@ -11,7 +11,6 @@ import (
 	"sneak.berlin/go/smallwebwaf/internal/alerts"
 	"sneak.berlin/go/smallwebwaf/internal/bans"
 	"sneak.berlin/go/smallwebwaf/internal/ratelimit"
-	"sneak.berlin/go/smallwebwaf/internal/reputation"
 	"sneak.berlin/go/smallwebwaf/internal/requestlog"
 )
 
@@ -206,57 +205,6 @@ func (rq *request) banForAttack(now time.Time, notes bans.Notes) string {
 	return banAction(ban.Permanent())
 }
 
-// banForCrowdSec bans the client's netblock at now until decision,
-// CrowdSec's decision on the client, ends. In observe mode it makes no
-// ban, and raises the alert for the ban it would have made, if that alert
-// would be sent. It returns the action for that ban.
-func (rq *request) banForCrowdSec(
-	now time.Time,
-	decision reputation.Decision,
-) string {
-	netblock := rq.h.netblock(rq.client)
-	if rq.h.config.Observe &&
-		!rq.wouldAlertBan(netblock, now, bans.CauseCrowdSec) {
-		return banAction(
-			rq.h.ledger.WouldBePermanent(netblock, now, bans.CauseCrowdSec),
-		)
-	}
-
-	notes := bans.Notes{
-		ASN:        rq.line.ASN,
-		ASName:     rq.line.ASName,
-		Country:    rq.line.Country,
-		Reputation: rq.reputation,
-		Request:    rq.noted(now, rq.h.config.BanResponse),
-		Requests:   rq.netblockRequests(netblock),
-	}
-
-	if rq.h.config.Observe {
-		ban, wouldBan := rq.h.ledger.WouldBanForCrowdSec(
-			netblock,
-			now,
-			decision.Expires,
-			decision.Scenario,
-			notes,
-		)
-		if wouldBan {
-			rq.alertBan(ban)
-		}
-
-		return banAction(ban.Permanent())
-	}
-
-	ban, made := rq.h.ledger.BanForCrowdSec(netblock, now, decision.Expires,
-		decision.Scenario, notes)
-	rq.line.BanExpires = banExpires(ban)
-
-	if made {
-		rq.alertBan(ban)
-	}
-
-	return banAction(ban.Permanent())
-}
-
 // wouldAlertBan reports whether the alert for a ban on netblock for cause
 // made at now would be sent. In observe mode the ban the request would
 // have made is worked out only then, at most once per

internal/waf/biased_test.go

@@ -387,14 +387,16 @@ func TestRequestWaitsForItsLookupWhileABiasedThresholdIsSet(t *testing.T) {
 
 			// In a synctest bubble, as
 			// TestRequestWaitsAsLongAsTheASNAndCountryLookupTimeoutSays says,
-			// with a GeoJS that never answers.
+			// with a GeoJS that never answers. The headers, which need the
+			// answer too, are off.
 			synctest.Test(t, func(t *testing.T) {
 				server, out, _ := newWAF(t, silentGeoJSURL, time.Now,
 					map[string]string{
 						asnAndCountryLookupTimeout: strconv.FormatInt(
 							timeout.Milliseconds(), 10),
-						tagLists:   "vpn=" + vpnList,
-						tc.setting: tc.value,
+						addLookupHeaders: falseValue,
+						tagLists:         "vpn=" + vpnList,
+						tc.setting:       tc.value,
 					})
 				began := time.Now()
 

internal/waf/countries_test.go

@@ -108,8 +108,11 @@ func TestCountryRefusalNamesItsHeuristicCountryAndSetting(t *testing.T) {
 	t.Parallel()
 
 	geojsURL, _ := startGeoJS(t)
+	// The headers are off, so that only the country list makes the request
+	// wait for its answer.
 	s, _, _ := startWithClock(t, geojsURL, map[string]string{
-		asnAndCountryLookupTimeout: "3600000", allowedCountries: "de",
+		asnAndCountryLookupTimeout: "3600000", addLookupHeaders: falseValue,
+		allowedCountries: "de",
 	})
 
 	line := s.get(
@@ -239,7 +242,10 @@ func TestPrivateAddressIsNeverLookedUp(t *testing.T) {
 		name string
 		env  map[string]string
 	}{
-		{"no setting needs the lookup", nil},
+		{
+			"no setting needs the lookup",
+			map[string]string{addLookupHeaders: falseValue},
+		},
 		{"a tag setting needs it", map[string]string{tagDeny: denyKP}},
 	} {
 		t.Run(tc.name, func(t *testing.T) {

internal/waf/crowdsec.go

@@ -1,54 +0,0 @@
-package waf
-
-// The heuristic crowdsec. It reads SWW_WAF_CROWDSEC_LAPI_URL, and the decisions
-// through the reputation lists.
-
-import (
-	"context"
-	"time"
-
-	"sneak.berlin/go/smallwebwaf/internal/bans"
-	"sneak.berlin/go/smallwebwaf/internal/config"
-	"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 adds the tag crowdsec, 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.addTag(config.CrowdSecTag)
-	rq.noteHit(bans.ReputationHit{Source: rq.h.config.CrowdSecDecisionsURL},
-		"listed by the CrowdSec decision list")
-
-	return &verdict{
-		action: rq.banForCrowdSec(now, decision),
-		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/waf/crowdsec_test.go

@@ -1,249 +0,0 @@
-package waf_test
-
-import (
-	"net/http"
-	"net/netip"
-	"reflect"
-	"testing"
-	"time"
-
-	"sneak.berlin/go/smallwebwaf/internal/alerts"
-	"sneak.berlin/go/smallwebwaf/internal/bans"
-	"sneak.berlin/go/smallwebwaf/internal/reputation"
-	"sneak.berlin/go/smallwebwaf/internal/requestlog"
-	"sneak.berlin/go/smallwebwaf/internal/waf"
-)
-
-// The CrowdSec settings, and the tests' engine, which is never asked: each
-// test puts in the copy of its decision list, at decisionsURL, that it
-// needs, as lists.json would at start.
-const (
-	crowdSecURL  = "SWW_WAF_CROWDSEC_LAPI_URL"
-	crowdSecKey  = "SWW_WAF_CROWDSEC_LAPI_KEY"
-	lapi         = "http://crowdsec.example:8080"
-	decisionsURL = lapi + "/v1/decisions"
-	bouncerKey   = "crowdsec-key-0123456789abcdef"
-)
-
-func TestClientTheCrowdSecDecisionListListsIsBannedUntilTheDecisionEnds(
-	t *testing.T,
-) {
-	t.Parallel()
-
-	s, clk, server, queue := startWithAlerts(t, map[string]string{
-		crowdSecURL: lapi, crowdSecKey: bouncerKey, metricsToken: token,
-	})
-	// client had four hours left on its decision as the engine answered.
-	fetched := clk.Now()
-	loadDecisions(t, server, fetched, `[{"duration": "4h0m0s", `+
-		`"scenario": "crowdsecurity/ssh-bf", "scope": "Ip", "type": "ban", `+
-		`"value": "`+client+`"}]`)
-	expires := requestlog.FormatTime(fetched.Add(4 * time.Hour))
-
-	// Its first request is refused, and bans it until the decision ends.
-	banned := requestlog.ActionTemporarilyBanned
-	line := s.get(client, http.StatusForbidden, banned)
-	wantReputation(t, line, decisionsURL)
-
-	if line.BanExpires != expires {
-		t.Errorf("log line has ban_expires %q, want %s",
-			line.BanExpires, expires)
-	}
-
-	listed := []bans.ReputationHit{{Source: decisionsURL}}
-
-	held := server.Ledger.Bans(netip.MustParsePrefix(client + "/32"))
-	if len(held) != 1 || held[0].Cause != bans.CauseCrowdSec ||
-		!held[0].Start.Equal(fetched) ||
-		!held[0].Expires.Equal(fetched.Add(4*time.Hour)) ||
-		held[0].Reason != "CrowdSec's decision for crowdsecurity/ssh-bf" ||
-		!reflect.DeepEqual(held[0].Notes.Reputation, listed) ||
-		held[0].Notes.Request.Path != "/" || held[0].Notes.Requests != 1 {
-		t.Fatalf(
-			"bans %+v, want one for crowdsec of four hours, with the list and "+
-				"the request in its notes",
-			held,
-		)
-	}
-
-	// The listing raises a reputation_hit alert, and the ban its own.
-	waiting := queue.Snapshot().Waiting[alerts.DestinationWebhook]
-	if len(waiting) != 2 || waiting[0].Event != alerts.EventReputationHit ||
-		waiting[0].Reason != "listed by the CrowdSec decision list" ||
-		!reflect.DeepEqual(
-			waiting[1],
-			banAlert(alerts.EventBan, fetched, client, held[0],
-				expires),
-		) {
-		t.Errorf(
-			"alerts waiting %+v, want a reputation_hit alert, then the ban's",
-			waiting,
-		)
-	}
-
-	// Each request while the ban lasts is refused under it, as under any
-	// ban, and once it has ended the client is let through.
-	clk.advance(4*time.Hour - time.Second)
-
-	line = s.get(client, http.StatusForbidden, banned)
-	wantReputation(t, line)
-
-	if line.BanExpires != expires {
-		t.Errorf("log line has ban_expires %q, want %s",
-			line.BanExpires, expires)
-	}
-
-	clk.advance(time.Second)
-	s.get(client, http.StatusOK, requestlog.ActionForward)
-
-	// The ban and the hit are counted, and the list has the metrics of any
-	// list fetched from a URL.
-	metrics := s.scrape()
-	labels := `{instance="` + alertInstance + `",source="` + decisionsURL + `"}`
-
-	wantMetric(t, metrics, `sww_bans_made_total{cause="crowdsec",`+
-		`instance="`+alertInstance+`"}`, 1)
-	wantMetric(t, metrics, "sww_reputation_hits_total"+labels, 1)
-	wantMetric(t, metrics, "sww_reputation_failures_total"+labels, 0)
-	wantMetric(
-		t,
-		metrics,
-		"sww_reputation_last_fetch_timestamp_seconds"+labels,
-		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.ActionTemporarilyBanned,
-	)
-	wantHeuristic(
-		t,
-		line,
-		"crowdsec",
-		`{"scenario": "crowdsecurity/ssh-bf", `+
-			`"expires": "`+requestlog.FormatTime(clk.Now().Add(4*time.Hour))+`"}`,
-	)
-	wantTags(t, line, "crowdsec")
-}
-
-func TestEndedCrowdSecDecisionNoLongerBansThoughTheCopyStillHoldsIt(
-	t *testing.T,
-) {
-	t.Parallel()
-
-	s, clk, server := startWithClock(t, "", map[string]string{
-		crowdSecURL: lapi, crowdSecKey: bouncerKey,
-	})
-	// 198.51.100.0/24 and 2001:db8::9 had a minute left as the engine
-	// answered.
-	fetched := clk.Now()
-	loadDecisions(t, server, fetched, `[{"duration": "1m0s", `+
-		`"scenario": "crowdsecurity/http-probing", "scope": "Range", "type": "ban", `+
-		`"value": "198.51.100.0/24"}, {"duration": "1m0s", `+
-		`"scenario": "crowdsecurity/http-probing", "scope": "Ip", "type": "ban", `+
-		`"value": "2001:db8::9"}]`)
-
-	// Just before its end, the decision bans a client in the netblock, and
-	// one on an IPv6 address bans the address's group, the /64.
-	clk.advance(time.Minute - time.Nanosecond)
-	s.get(
-		"198.51.100.7",
-		http.StatusForbidden,
-		requestlog.ActionTemporarilyBanned,
-	)
-	s.get(
-		"2001:db8::9",
-		http.StatusForbidden,
-		requestlog.ActionTemporarilyBanned,
-	)
-	s.get(
-		"2001:db8::5",
-		http.StatusForbidden,
-		requestlog.ActionTemporarilyBanned,
-	)
-
-	// Once it has ended, it bans no other client, and the bans it made end
-	// with it.
-	clk.advance(time.Nanosecond)
-
-	for _, from := range []string{"198.51.100.8", "198.51.100.7", "2001:db8::5"} {
-		wantReputation(
-			t,
-			s.get(from, http.StatusOK, requestlog.ActionForward),
-		)
-	}
-
-	if made := server.Ledger.Made(bans.CauseCrowdSec); made != 2 {
-		t.Errorf(
-			"%d bans made for crowdsec, want 2, on 198.51.100.7/32 and "+
-				"2001:db8::/64",
-			made,
-		)
-	}
-
-	if held := server.Ledger.Bans(netip.MustParsePrefix("2001:db8::/64")); len(
-		held,
-	) != 1 {
-		t.Errorf("bans of 2001:db8::/64 %+v, want one", held)
-	}
-}
-
-func TestObserveModeForwardsAClientTheCrowdSecDecisionListListsAndAlertsTheBan(
-	t *testing.T,
-) {
-	t.Parallel()
-
-	s, clk, server, queue := startWithAlerts(t, map[string]string{
-		crowdSecURL: lapi, crowdSecKey: bouncerKey, mode: observe,
-	})
-	loadDecisions(t, server, clk.Now(), `[{"duration": "4h0m0s", `+
-		`"scenario": "crowdsecurity/ssh-bf", "scope": "Ip", "type": "ban", `+
-		`"value": "`+client+`"}]`)
-
-	line := s.get(client, http.StatusOK, requestlog.ActionForward)
-	wantWouldAction(t, line, requestlog.ActionTemporarilyBanned)
-	wantReputation(t, line, decisionsURL)
-
-	if held := server.Ledger.Snapshot(); len(held) != 0 {
-		t.Errorf("bans %+v, want none", held)
-	}
-
-	waiting := queue.Snapshot().Waiting[alerts.DestinationWebhook]
-	if len(waiting) != 2 || waiting[1].Event != alerts.EventBan ||
-		waiting[1].Detail["cause"] != bans.CauseCrowdSec ||
-		waiting[1].Detail["mode"] != observe {
-		t.Errorf(
-			"alerts waiting %+v, want a reputation_hit alert, then the ban alert "+
-				"marked observe",
-			waiting,
-		)
-	}
-}
-
-// loadDecisions puts into server's lists the copy of the decision list at
-// decisionsURL, answer, the engine's answer, fetched at fetched, as
-// lists.json would at start.
-func loadDecisions(
-	t *testing.T, server *waf.Server, fetched time.Time, answer string,
-) {
-	t.Helper()
-
-	err := server.Lists.Load([]reputation.List{{
-		URL: decisionsURL, Tried: fetched, Fetched: fetched, Lines: []string{answer},
-	}})
-	if err != nil {
-		t.Fatalf("load the decision list: %v", err)
-	}
-}

internal/waf/headerlimits.go

@@ -10,16 +10,22 @@ import (
 	"sneak.berlin/go/smallwebwaf/internal/requestlog"
 )
 
-// The header limits: the most cookies and header fields a request may have.
-// Real clients never reach them.
+// The header limits: the most cookies and header fields a request may have,
+// and the longest its request line and each header line may be, in bytes, not
+// counting the line ending. Real clients rarely reach them. maxLineBytes is
+// what nginx allows by default.
 const (
 	maxCookies      = 50
 	maxHeaderFields = 100
+	maxLineBytes    = 8 << 10
 )
 
-// headerLimits refuses a request with more than maxHeaderFields header fields
-// or more than maxCookies cookies, with 431. Its figures are the request's
-// header fields and cookies, and the limit of each.
+// headerLimits refuses a request with a request line longer than maxLineBytes,
+// with 414. It refuses a request with a header line longer than maxLineBytes,
+// more than maxHeaderFields header fields or more than maxCookies cookies, with
+// 431. Its figures are the request line's length and its limit for 414. For
+// 431 they are the longest header line, the header fields and the cookies,
+// each with its limit.
 type headerLimits struct{}
 
 func (headerLimits) name() string { return "header_limits" }
@@ -29,20 +35,59 @@ func (headerLimits) check(
 	rq *request,
 	_ time.Time,
 ) *verdict {
+	requestLine := rq.requestLineBytes()
+	if requestLine > maxLineBytes {
+		return &verdict{
+			action: requestlog.ActionRequestLineTooLong,
+			figures: map[string]any{
+				"request_line_bytes":       requestLine,
+				"request_line_bytes_limit": maxLineBytes,
+			},
+		}
+	}
+
+	longest := rq.longestHeaderLineBytes()
 	fields, cookies := rq.headerCounts()
-	if fields <= maxHeaderFields && cookies <= maxCookies {
+
+	if longest <= maxLineBytes && fields <= maxHeaderFields &&
+		cookies <= maxCookies {
 		return nil
 	}
 
 	return &verdict{
 		action: requestlog.ActionRequestHeaderTooLarge,
 		figures: map[string]any{
-			"fields": fields, "fields_limit": maxHeaderFields,
+			"longest_header_line_bytes": longest,
+			"header_line_bytes_limit":   maxLineBytes,
+			"fields":                    fields, "fields_limit": maxHeaderFields,
 			"cookies": cookies, "cookies_limit": maxCookies,
 		},
 	}
 }
 
+// requestLineBytes returns the length of the request's request line, such as
+// "GET /search?q=x HTTP/1.1", not counting its line ending. The target is the
+// one the visitor sent, which rproxy's question carries unchanged.
+func (rq *request) requestLineBytes() int {
+	return len(rq.in.Method) + len(" ") + len(rq.in.RequestURI) +
+		len(" ") + len(rq.in.Proto)
+}
+
+// longestHeaderLineBytes returns the length of the request's longest header
+// line, such as "Cookie: a=1", not counting its line ending. Each value of a
+// header sent twice is a line of its own, and Host is a line too.
+func (rq *request) longestHeaderLineBytes() int {
+	longest := len("Host: ") + len(rq.in.Host)
+
+	for name, values := range rq.in.Header {
+		for _, value := range values {
+			longest = max(longest, len(name)+len(": ")+len(value))
+		}
+	}
+
+	return longest
+}
+
 // 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

internal/waf/heuristics.go

@@ -41,8 +41,8 @@ const (
 
 // 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.
-// header_limits comes first: it only counts, and a request it refuses causes no
-// other work.
+// header_limits comes first: it only measures and counts, and a request it
+// refuses causes no other work.
 func beforeLookup() []heuristic {
 	return []heuristic{
 		headerLimits{},
@@ -60,7 +60,6 @@ func afterLookup() []heuristic {
 	return []heuristic{
 		countries{},
 		blocklists{},
-		crowdSec{},
 		dnsbl{},
 		abuseIPDB{},
 		tagDeny{},

internal/waf/lookup.go

@@ -12,7 +12,7 @@ import (
 )
 
 // The headers in which an answer of allow gives rproxy the client's AS number
-// and country, for the app, while SWW_WAF_ADD_LOOKUP_HEADERS is set. Go writes
+// and country, for the app, while SWW_WAF_ADD_LOOKUP_HEADERS is true. 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 (

internal/waf/lookup_test.go

@@ -36,6 +36,7 @@ func TestEveryClientIsLookedUpWithoutWaitingWhileNoSettingNeedsIt(
 	geojsURL, asked, release := startHeldGeoJS(t)
 	s, _, server := startWithClock(t, geojsURL, map[string]string{
 		asnAndCountryLookupTimeout: "3600000",
+		addLookupHeaders:           falseValue,
 		rateLimitPerMinute:         "1",
 	})
 
@@ -418,7 +419,7 @@ func TestClientsOwnLookupHeadersAreRemovedWhileTheSettingIsOff(
 		geojsURL,
 		time.Now,
 		map[string]string{
-			trustedProxies: trustLocalhost,
+			trustedProxies: trustLocalhost, addLookupHeaders: falseValue,
 		},
 	)
 	s := &sender{t: t, addr: addr, out: out}
@@ -457,6 +458,8 @@ func TestRequestWaitsAsLongAsTheASNAndCountryLookupTimeoutSays(
 			map[string]string{
 				asnAndCountryLookupTimeout: strconv.FormatInt(
 					timeout.Milliseconds(), 10),
+				// Off, so that only the country list makes the request wait.
+				addLookupHeaders: falseValue,
 				allowedCountries: "DE",
 			})
 

internal/waf/proxy.go

@@ -75,8 +75,8 @@ type Params struct {
 	Rules *rules.Files
 	// Alerts receive the alert for each ban waf 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
+	// whose client a blocklist, a DNSBL zone or AbuseIPDB lists, for each
+	// request the Core Rule Set scores at or over
 	// SWW_WAF_CORE_RULE_SET_SCORE_THRESHOLD, and for GeoJS failing, a fetch of a list
 	// failing, a query to a DNSBL zone or a check with AbuseIPDB failing,
 	// or the day's AbuseIPDB checks used up.
@@ -194,11 +194,13 @@ func newReputation(
 ) (*reputation.Lists, *reputation.DNSBL, *reputation.AbuseIPDB) {
 	cfg := params.Config
 	lists := reputation.New(reputation.Params{
-		BlocklistURLs: cfg.BlocklistURLs, Refresh: cfg.BlocklistRefresh,
-		ASNLimitPercentURL:   cfg.ASNLimitPercentURL,
-		TagLists:             cfg.TagLists,
-		CrowdSecDecisionsURL: cfg.CrowdSecDecisionsURL, CrowdSecKey: cfg.CrowdSecKey,
-		Now: params.Now, ProcessLog: params.ProcessLog, Alerts: params.Alerts,
+		BlocklistURLs:      cfg.BlocklistURLs,
+		Refresh:            cfg.BlocklistRefresh,
+		ASNLimitPercentURL: cfg.ASNLimitPercentURL,
+		TagLists:           cfg.TagLists,
+		Now:                params.Now,
+		ProcessLog:         params.ProcessLog,
+		Alerts:             params.Alerts,
 	})
 	dnsbl := reputation.NewDNSBL(reputation.DNSBLParams{
 		Zones: cfg.DNSBLZones, Resolver: cfg.DNSBLResolver,
@@ -226,12 +228,9 @@ func newReputation(
 // without the rules SWW_WAF_CORE_RULE_SET_DISABLED_RULES switches off, reading bodies
 // up to SWW_WAF_CORE_RULE_SET_BODY_INSPECTION_SIZE, with the exclusions in
 // SWW_WAF_CORE_RULE_SET_EXCLUSIONS_FILE and the fixes of the apps in SWW_WAF_APPS,
-// or nil while SWW_WAF_CORE_RULE_SET_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. An exclusions file that coreruleset.New refuses is
-// an error in every mode. While the mode is off, a set file is loaded with the
-// Core Rule Set only to check it.
+// or nil while SWW_WAF_CORE_RULE_SET_MODE is off. An exclusions file that
+// coreruleset.New refuses is an error in every mode. While the mode is off, a
+// set file is loaded with the Core Rule Set only to check it.
 func NewCoreRuleSet(cfg *config.WAF) (*coreruleset.CoreRuleSet, error) {
 	if cfg.CoreRuleSetMode == config.CoreRuleSetModeOff &&
 		cfg.CoreRuleSetExclusionsFile == "" {
@@ -239,14 +238,11 @@ func NewCoreRuleSet(cfg *config.WAF) (*coreruleset.CoreRuleSet, error) {
 	}
 
 	coreRuleSet, err := coreruleset.New(coreruleset.Params{
-		ParanoiaLevel: cfg.CoreRuleSetParanoiaLevel,
-		DisabledRules: cfg.CoreRuleSetDisabledRules,
-		BodyInspectionSize: min(
-			cfg.CoreRuleSetBodyInspectionSize,
-			QuestionBodyMaxBytes-1,
-		),
-		ExclusionsFile: cfg.CoreRuleSetExclusionsFile,
-		Apps:           cfg.Apps,
+		ParanoiaLevel:      cfg.CoreRuleSetParanoiaLevel,
+		DisabledRules:      cfg.CoreRuleSetDisabledRules,
+		BodyInspectionSize: cfg.CoreRuleSetBodyInspectionSize,
+		ExclusionsFile:     cfg.CoreRuleSetExclusionsFile,
+		Apps:               cfg.Apps,
 	})
 	if err != nil {
 		return nil, fmt.Errorf(

internal/waf/proxy_test.go

@@ -93,6 +93,10 @@ const off = "off"
 // on is the value that switches a setting that takes true or false on.
 const on = "true"
 
+// falseValue is the value that switches a setting that takes true or false
+// off.
+const falseValue = "false"
+
 // output collects what sww writes on stdout.
 type output struct {
 	mu  sync.Mutex

internal/waf/reputation.go

@@ -1,7 +1,6 @@
 package waf
 
-// What the reputation heuristics share: blocklists, crowdsec, dnsbl and
-// abuseipdb.
+// What the reputation heuristics share: blocklists, dnsbl and abuseipdb.
 
 import (
 	"sneak.berlin/go/smallwebwaf/internal/alerts"

internal/waf/request.go

@@ -177,7 +177,7 @@ func requestHeaders(r *http.Request, names []string) map[string]string {
 // 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 SWW_WAF_BAN_RESPONSE, 403 for a block rule or the Core
-// Rule Set, or 431 for the header limits. In observe mode nothing is refused,
+// Rule Set, or 414 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 {
@@ -196,6 +196,8 @@ func (rq *request) check(ctx context.Context) *refusal {
 	case action == requestlog.ActionBlockedByBlockRule ||
 		action == requestlog.ActionBlockedByCoreRuleSet:
 		return &refusal{status: http.StatusForbidden, action: action}
+	case action == requestlog.ActionRequestLineTooLong:
+		return &refusal{status: http.StatusRequestURITooLong, action: action}
 	case action == requestlog.ActionRequestHeaderTooLarge:
 		return &refusal{
 			status: http.StatusRequestHeaderFieldsTooLarge,

internal/waf/waf.go

@@ -146,18 +146,15 @@ func (h *handler) ServeHTTP(w http.ResponseWriter, r *http.Request) {
 
 // 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: the heuristic crowdsec, blocklists or rate_limits will refuse it,
-// as a function in that heuristic's file says. In observe mode, which refuses
+// its client: the heuristic 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 waf answers too late.
 func (rq *request) refusedWhateverTheAnswer(now time.Time) bool {
 	if rq.h.config.Observe {
 		return false
 	}
 
-	_, decided := rq.crowdSecDecisionInForce(now)
-
-	return decided ||
-		rq.refusedByBlocklists(rq.h.lists.ListedBy(rq.client)) ||
+	return rq.refusedByBlocklists(rq.h.lists.ListedBy(rq.client)) ||
 		rq.overAWholeRateLimit(now)
 }
 
@@ -323,7 +320,7 @@ func asTheVisitorSentIt(r *http.Request, body []byte) *http.Request {
 }
 
 // allow answers a question with DispositionAllow and, while
-// SWW_WAF_ADD_LOOKUP_HEADERS is set, the client's AS number and country.
+// SWW_WAF_ADD_LOOKUP_HEADERS is true, the client's AS number and country.
 func (rq *request) allow() {
 	rq.allowed = true
 

internal/waf/waf_test.go

@@ -869,7 +869,7 @@ func TestAllowCarriesTheLookupHeadersWhileTheSettingIsSet(t *testing.T) {
 		wantASN, wantCountry string
 	}{
 		{on, "AS64496", "DE"},
-		{"false", "", ""},
+		{falseValue, "", ""},
 	} {
 		t.Run(tc.setting, func(t *testing.T) {
 			t.Parallel()
@@ -1690,7 +1690,12 @@ func TestALargeBodyAnnouncedAndLongHeadersAreNoReasonToRefuse(t *testing.T) {
 		strings.NewReader("a body"))
 	req.Header.Set(waf.ContentLengthHeader, "1073741824")
 	req.Header.Set(forwardedFor, otherClient)
-	req.Header.Set("X-Long", strings.Repeat("x", 40<<10))
+
+	// 40,000 bytes of headers, over rproxy's 32 KiB, in lines within the
+	// header limits.
+	for i := range 5 {
+		req.Header.Set("X-Long-"+strconv.Itoa(i), strings.Repeat("x", 8000))
+	}
 
 	got := do(t, req)
 	wantDisposition(t, got, http.StatusOK, waf.DispositionAllow)
@@ -1782,7 +1787,7 @@ func TestCoreRuleSetReadsTheBodyAQuestionCarries(t *testing.T) {
 	t.Parallel()
 
 	s := startWAF(t, "", map[string]string{
-		coreRuleSetMode: block, coreRuleSetBodyInspectionSize: "64K",
+		coreRuleSetMode: block, coreRuleSetBodyInspectionSize: "8K",
 	})
 
 	ask := func(contentType, body string) answer {
@@ -1797,10 +1802,10 @@ func TestCoreRuleSetReadsTheBodyAQuestionCarries(t *testing.T) {
 	got := ask(formData, "id=1'%20OR%20'1'='1")
 	wantDisposition(t, got, http.StatusForbidden, waf.DispositionDeny)
 
-	// The first 64 KiB of a longer JSON body cannot be parsed, which is no
+	// The first 8 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", waf.QuestionBodyMaxBytes)
-	got = ask("application/json", cut[:waf.QuestionBodyMaxBytes])
+	cut := `{"text":"` + strings.Repeat("x", 8<<10)
+	got = ask("application/json", cut)
 	wantDisposition(t, got, http.StatusOK, waf.DispositionAllow)
 }