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sneak/smallwebwaf:main sneak/smallwebwaf:docs-audit-203 sneak/smallwebwaf:issue-175-request-tags sneak/smallwebwaf:next sneak/smallwebwaf:issue-220-apps-by-hostname sneak/smallwebwaf:issue-216-oci-labels sneak/smallwebwaf:issue-211-viper-config sneak/smallwebwaf:readme-rewrite-155
sneak/smallwebwaf:v1.0.0-rc2 sneak/smallwebwaf:v1.0.0-rc1
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compare: sneak/smallwebwaf:c350411acc279f8b95676dc24eeecde8f2a35781
sneak/smallwebwaf:docs-audit-203 sneak/smallwebwaf:issue-175-request-tags sneak/smallwebwaf:next sneak/smallwebwaf:issue-220-apps-by-hostname sneak/smallwebwaf:issue-216-oci-labels sneak/smallwebwaf:issue-211-viper-config sneak/smallwebwaf:main sneak/smallwebwaf:readme-rewrite-155
sneak/smallwebwaf:v1.0.0-rc2 sneak/smallwebwaf:v1.0.0-rc1
1 Commits
docs-audit-203 .. c350411acc
Author SHA1 Message Date
sneak c350411acc Quiet the update-alternatives man page warnings in the image build (closes #222)
check / check (push) Successful in 3m59s
Details 
xz-utils' install calls update-alternatives to link its man pages, but the
image's dpkg config drops man pages the moment they unpack, so it prints
one warning for each link it cannot make. A config file read after that one
re-includes man pages for this install alone, so the links are made
quietly; the man pages and that file are then removed, so the image still
holds none, and installs built from it still drop them.

Model: deepseek-v4-pro
 2026-11-07 12:49:47 +00:00
46 changed files with 642 additions and 1537 deletions
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Dockerfile
+9 -9
View File
@@ -137,18 +137,18 @@ RUN mkdir /etc/sysusers.d \
# them over plain HTTP and checks each one against the archive's signed # them over plain HTTP and checks each one against the archive's signed
# package lists, so no CA certificates are needed. # package lists, so no CA certificates are needed.
# #
# nix-bin depends on xz-utils, whose install links man pages with # The image's dpkg config drops man pages as each package unpacks, so
# update-alternatives. The image's dpkg config drops man pages, so each # xz-utils' install prints an update-alternatives warning for every man-page
# link warns. z-man, read after /etc/dpkg/dpkg.cfg.d/excludes, re-includes # link it cannot make. This side file re-includes them for this install
# the man1 pages for this install alone; the same step deletes them again, # alone; it is named to be read after /etc/dpkg/dpkg.cfg.d/excludes, so it
# so no man page or package is added. # overrides that drop. The man pages and the side file are removed again
RUN echo 'path-include=/usr/share/man/man1/*' > /etc/dpkg/dpkg.cfg.d/z-man \ # below, so the image keeps no man pages, and installs built from it still
# drop them.
RUN echo 'path-include=/usr/share/man/*' > /etc/dpkg/dpkg.cfg.d/z-man \
&& apt-get update \ && apt-get update \
&& DEBIAN_FRONTEND=noninteractive apt-get install --yes --no-install-recommends \ && DEBIAN_FRONTEND=noninteractive apt-get install --yes --no-install-recommends \
ca-certificates nix-bin runit \ ca-certificates nix-bin runit \
&& rm -rf /var/lib/apt/lists/* /etc/dpkg/dpkg.cfg.d/z-man \ && rm -rf /var/lib/apt/lists/* /usr/share/man /etc/dpkg/dpkg.cfg.d/z-man
&& find /usr/share/man/man1 ! -type d -delete \
&& find /etc/alternatives -type l -xtype l -delete
# Nix run by root expects a group of build users, which nix-bin does not # Nix run by root expects a group of build users, which nix-bin does not
# create; with the setting empty, root's builds run without them. # create; with the setting empty, root's builds run without them.
EVALUATION.md
+38 -39
View File
@@ -12,8 +12,8 @@ configured only by environment variables, that provides:
- R1: rate limits per minute, per hour and per day - R1: rate limits per minute, per hour and per day
- R2: netblocks that bypass rate limiting - R2: netblocks that bypass rate limiting
- R3: alerts on attacks through webhook, Slack or ntfy - R3: alerts on attacks through webhook, Slack or ntfy
- R4: alerts on anomalies: requests made or bytes transferred per minute or - R4: alerts on anomalies: requests or bytes per minute or hour, for given IPs
hour, for given IPs or netblocks, crossing a threshold or netblocks, crossing a threshold
- R5: temporary blocks for abusers, permanent bans for repeat offenders - R5: temporary blocks for abusers, permanent bans for repeat offenders
- R6: one or more RBLs or IP reputation APIs - R6: one or more RBLs or IP reputation APIs
- R7: AS number lookup - R7: AS number lookup
@@ -25,13 +25,13 @@ configured only by environment variables, that provides:
## Verdict ## Verdict
Nothing existing is suitable. No surveyed tool meets R8 (scaling limits by AS Nothing existing is suitable. No surveyed tool meets R8 (scaling limits by AS
number or country) or R4's alerts on bytes transferred, and the tools that come number or country) or the bytes half of R4 at all, and the tools that come
closest on the rest fail R10: they need several containers, YAML or a web UI. closest on the rest fail R10: they need several containers, YAML or a web UI.
The recommendation is to build a small single-binary sidecar; `SPEC.md` in this The recommendation is to build a small single-binary sidecar; `SPEC.md` in this
directory begins that spec. The sidecar reuses the mature parts of the surveyed directory begins that spec. It reuses the mature parts of the surveyed field as
field as libraries and data sources (Coraza and the OWASP Core Rule Set for libraries and data sources (Coraza and the OWASP Core Rule Set for attack
attack detection, DNSBLs, AbuseIPDB, optionally a CrowdSec decision feed) detection, DNSBLs, AbuseIPDB, optionally a CrowdSec decision feed) instead of
instead of reimplementing them. reimplementing them.
Closest existing options, and why each still falls short: Closest existing options, and why each still falls short:
@@ -46,12 +46,12 @@ Closest existing options, and why each still falls short:
blacklist and whitelist decisions), R9 (ModSecurity with the Core Rule blacklist and whitelist decisions), R9 (ModSecurity with the Core Rule
Set, or Coraza plugin), env-var settings. Set, or Coraza plugin), env-var settings.
- Fails: R8 (AS number and country can only allow or deny, never scale a - Fails: R8 (AS number and country can only allow or deny, never scale a
limit), R4 (no alerts on request-count or byte thresholds in the free limit), R4 (no volume or byte threshold alerts in the free edition;
edition; reporting is a paid feature), R5 escalation, and R10's plain reporting is a paid feature), R5 escalation, and R10 in spirit: since 1.6
sidecar: since 1.6 it needs a `bunkerweb` container plus a `bw-scheduler` it needs a `bunkerweb` container plus a `bw-scheduler` container and a
container and a database, or the all-in-one image that bundles nginx, database, or the all-in-one image that bundles nginx, scheduler, UI and
scheduler, UI and Redis in one container. It is designed as the proxy in Redis in one container. It is designed to be the front door for many
front of many sites, not as a sidecar for one app. AGPL-3.0. sites, not a per-app sidecar. AGPL-3.0.
- Unverified: whether several rates (minute, hour, day) can be stacked on - Unverified: whether several rates (minute, hour, day) can be stacked on
the same URL pattern; the documented design is one rate per URL pattern. the same URL pattern; the documented design is one rate per URL pattern.
- CrowdSec is the strongest detection and ban engine, but it is not a proxy. - CrowdSec is the strongest detection and ban engine, but it is not a proxy.
@@ -68,15 +68,14 @@ Closest existing options, and why each still falls short:
answers 429. answers 429.
- Fails: R10 (needs the security engine container with persistent state, log - Fails: R10 (needs the security engine container with persistent state, log
acquisition from traefik, a bouncer such as the traefik plugin, and YAML acquisition from traefik, a bouncer such as the traefik plugin, and YAML
for acquisition, profiles, scenarios and notifications), R4's alerts on for acquisition, profiles, scenarios and notifications), bytes half of R4.
bytes.
- CrowdSec plus traefik's own `rateLimit` middleware is the best combination - CrowdSec plus traefik's own `rateLimit` middleware is the best combination
with no new code. It gives inline limiting (one window per middleware, keyed with no new code. It gives inline limiting (one window per middleware, keyed
by IP, with `sourceCriterion` exclusions), bans with escalation, alerts and by IP, with `sourceCriterion` exclusions), bans with escalation, alerts and
reputation lookups. It still fails R8, R4's alerts on bytes, and R10 entirely: reputation. It still fails R8, the bytes half of R4, R1's three stacked
the configuration lives in traefik labels and CrowdSec YAML on each host, not windows only by chaining three middlewares per router, and R10 entirely: the
in one sidecar's environment. It meets R1's three windows only by chaining configuration lives in traefik labels and CrowdSec YAML on each host, not in
three middlewares per router. one sidecar's environment.
## Candidate by candidate ## Candidate by candidate
@@ -88,10 +87,10 @@ Closest existing options, and why each still falls short:
cached, streamed decision list (recommended), standalone against the cached, streamed decision list (recommended), standalone against the
central API, or AppSec only. Supports captcha remediation. central API, or AppSec only. Supports captcha remediation.
- Covers: R5, R6, R9, R3 and R7 through the engine (see Verdict). - Covers: R5, R6, R9, R3 and R7 through the engine (see Verdict).
- Misses: the plugin itself does no rate limiting; R8; R4's alerts on bytes. - Misses: the plugin itself does no rate limiting; R8; R4 bytes.
- Configuration: traefik static config to load the plugin, dynamic config or - Configuration: traefik static config to load the plugin, dynamic config or
labels for the middleware, CrowdSec YAML for everything else. labels for the middleware, CrowdSec YAML for everything else.
- Sidecar fit: no. It runs inside traefik and needs a separate engine - Sidecar fit: no. It lives inside traefik, plus a separate engine
container. container.
- Maturity: widely used (about 900 stars, listed in the traefik plugin - Maturity: widely used (about 900 stars, listed in the traefik plugin
catalog, documented by CrowdSec itself), actively maintained. Traefik catalog, documented by CrowdSec itself), actively maintained. Traefik
@@ -116,7 +115,7 @@ Closest existing options, and why each still falls short:
- What it is: nginx-derived (Tengine) reverse proxy with a proprietary - What it is: nginx-derived (Tengine) reverse proxy with a proprietary
semantic detection engine and a web console. About 22,000 stars. semantic detection engine and a web console. About 22,000 stars.
- Covers: R9 well, basic per-IP rate limiting with block duration, bot - Covers: R9 well, basic per-IP rate limiting with block duration, bot
challenge, authentication in front of the app. challenge, authentication gate.
- Misses: R8, R7, R4; R1 has one window per rule. Country blocking, alert - Misses: R8, R7, R4; R1 has one window per rule. Country blocking, alert
messages, syslog forwarding and the better reputation database are paid messages, syslog forwarding and the better reputation database are paid
(Lite about 10 USD per month, Pro about 100 USD per month); the free (Lite about 10 USD per month, Pro about 100 USD per month); the free
@@ -129,7 +128,7 @@ Closest existing options, and why each still falls short:
- Coraza (`corazawaf/coraza`) and Coraza-based proxies - Coraza (`corazawaf/coraza`) and Coraza-based proxies
- What it is: a Go library that implements the ModSecurity rule language and - What it is: a Go library that implements the ModSecurity rule language and
runs the OWASP Core Rule Set. OWASP project, actively maintained, the runs the OWASP Core Rule Set. OWASP project, actively maintained, the
successor to ModSecurity, which is now in maintenance only. successor path now that ModSecurity is in maintenance only.
- Packagings: `coraza-caddy` (Caddy module), `coraza-spoa` (HAProxy), - Packagings: `coraza-caddy` (Caddy module), `coraza-spoa` (HAProxy),
`coraza-proxy-wasm` (Envoy), a traefik WASM plugin, and `coraza-proxy-wasm` (Envoy), a traefik WASM plugin, and
`coreruleset/coraza-crs-docker` (Caddy plus Coraza plus the Core Rule Set, `coreruleset/coraza-crs-docker` (Caddy plus Coraza plus the Core Rule Set,
@@ -143,7 +142,7 @@ Closest existing options, and why each still falls short:
- ModSecurity Core Rule Set containers (`owasp/modsecurity-crs`) - ModSecurity Core Rule Set containers (`owasp/modsecurity-crs`)
- What it is: official images of Apache or nginx with ModSecurity and the - What it is: official images of Apache or nginx with ModSecurity and the
Core Rule Set, as a reverse proxy configured by env vars (`BACKEND`, Core Rule Set, as a reverse proxy configured by env vars (`BACKEND`,
paranoia level, anomaly thresholds, many more). Current images contain paranoia level, anomaly thresholds, many more). Current images carry
ModSecurity 2.9.x on Apache and Core Rule Set 4.x. ModSecurity 2.9.x on Apache and Core Rule Set 4.x.
- Covers: R9, and R10 (single container, env vars, one backend). - Covers: R9, and R10 (single container, env vars, one backend).
- Misses: R1 to R8. - Misses: R1 to R8.
@@ -153,8 +152,8 @@ Closest existing options, and why each still falls short:
- Anubis (`TecharoHQ/anubis`), 1.27 current - Anubis (`TecharoHQ/anubis`), 1.27 current
- What it is: a single-binary reverse proxy that makes browsers solve a - What it is: a single-binary reverse proxy that makes browsers solve a
proof-of-work challenge before passing them to `TARGET`. Aimed at proof-of-work challenge before passing them to `TARGET`. Aimed at
scrapers, which are likely a large share of the unwanted traffic on a scrapers, which is likely a large share of unwanted traffic on a public
public code forge. code forge.
- Covers: R10 well (one container, env vars for listener, target, - Covers: R10 well (one container, env vars for listener, target,
difficulty, cookies). Policy rules can match on path, user agent, headers, difficulty, cookies). Policy rules can match on path, user agent, headers,
IP ranges, and with the vendor's hosted data service also AS number and IP ranges, and with the vendor's hosted data service also AS number and
@@ -181,13 +180,13 @@ Closest existing options, and why each still falls short:
temporary ban, no escalation, state lost on traefik restart) and R2 temporary ban, no escalation, state lost on traefik restart) and R2
(allowlist). Nothing else. (allowlist). Nothing else.
- `juitde/traefik-plugin-fail2ban`, fail2ban connector plugins, GeoBlock - `juitde/traefik-plugin-fail2ban`, fail2ban connector plugins, GeoBlock
plugins (country allow or deny through an external lookup API): each adds plugins (country allow or deny through an external lookup API): same
one small feature, is configured in traefik and keeps its state in memory. shape, each one small feature, configured in traefik, state in memory.
- Sidecar fit: no; they live inside traefik. - Sidecar fit: no; they live inside traefik.
- Traefik built-in middlewares - Traefik built-in middlewares
- `rateLimit` (one average-and-burst window per middleware, optional Redis - `rateLimit` (one average-and-burst window per middleware, optional Redis
in traefik 3.x), `inFlightReq`, `ipAllowList`. No bans, alerts, reputation in traefik 3.x), `inFlightReq`, `ipAllowList`. No bans, alerts, reputation
lookups or AS number lookups. or AS number awareness.
- caddy-waf (`fabriziosalmi/caddy-waf`), 0.4.x - caddy-waf (`fabriziosalmi/caddy-waf`), 0.4.x
- What it is: a Caddy module with regex rules and anomaly scoring, per-IP - What it is: a Caddy module with regex rules and anomaly scoring, per-IP
and per-path rate limiting with one configurable window, IP and DNS and per-path rate limiting with one configurable window, IP and DNS
@@ -199,12 +198,12 @@ Closest existing options, and why each still falls short:
- open-appsec (Check Point) - open-appsec (Check Point)
- Machine-learning WAF agent attached to nginx, Kong, Envoy or similar, with - Machine-learning WAF agent attached to nginx, Kong, Envoy or similar, with
a declarative policy file or the vendor's cloud console. Covers R9 only; a declarative policy file or the vendor's cloud console. Covers R9 only;
rate limiting and richer features are in paid tiers. It attaches to an rate limiting and richer features are in paid tiers. Not a sidecar in the
existing proxy, so it is not the sidecar R10 asks for. required sense.
- iocaine - iocaine
- Serves generated garbage pages to clients the fronting proxy classifies as - Serves generated garbage pages to clients the fronting proxy classifies as
scrapers. Not a limiter, WAF or ban tool; out of scope, and only of scrapers. Not a limiter, WAF or ban tool; out of scope except as a
passing interest for scraper traffic. curiosity for scraper traffic.
- Pangolin - Pangolin
- A tunnelled access platform that bundles traefik and optionally CrowdSec. - A tunnelled access platform that bundles traefik and optionally CrowdSec.
Replaces the ingress rather than adding a sidecar; out of scope. Replaces the ingress rather than adding a sidecar; out of scope.
@@ -215,17 +214,17 @@ Closest existing options, and why each still falls short:
Everyone else offers one window per rule or none. Everyone else offers one window per rule or none.
- R2 bypass netblocks: BunkerWeb, CrowdSec, traefik, fail2ban plugins. - R2 bypass netblocks: BunkerWeb, CrowdSec, traefik, fail2ban plugins.
- R3 alerts: CrowdSec (best), BunkerWeb (denied requests only), SafeLine (paid). - R3 alerts: CrowdSec (best), BunkerWeb (denied requests only), SafeLine (paid).
- R4 alerts on request counts and bytes: none. CrowdSec can approximate alerts - R4 volume and byte anomalies: none. CrowdSec can approximate request-count
on request counts with a custom scenario; no surveyed tool alerts on bytes. anomalies with a custom scenario; nothing handles bytes.
- R5 temporary then permanent: CrowdSec only. BunkerWeb's ban is either one - R5 temporary then permanent: CrowdSec only. BunkerWeb has fixed or permanent,
fixed length or permanent, and does not change with a client's history. not both by history.
- R6 reputation: CrowdSec, BunkerWeb, go-away, caddy-waf (static lists). - R6 reputation: CrowdSec, BunkerWeb, go-away, caddy-waf (static lists).
- R7 AS number lookup: CrowdSec (enrichment), BunkerWeb and caddy-waf (allow or - R7 AS number lookup: CrowdSec (enrichment), BunkerWeb and caddy-waf (allow or
deny), Anubis (hosted service). deny), Anubis (hosted service).
- R8 biased thresholds: none. - R8 biased thresholds: none.
- R9 attack detection: Coraza or ModSecurity with the Core Rule Set (open, - R9 attack detection: Coraza or ModSecurity with the Core Rule Set (open,
standard), CrowdSec AppSec, SafeLine (closed engine), BunkerWeb (wraps Coraza standard), CrowdSec AppSec, SafeLine (closed engine), BunkerWeb (wraps the
or ModSecurity). first).
- R10 env-var sidecar: `owasp/modsecurity-crs`, `coraza-crs-docker`, Anubis. - R10 env-var sidecar: `owasp/modsecurity-crs`, `coraza-crs-docker`, Anubis.
None of these covers anything beyond its one job. None of these covers anything beyond its one job.
Makefile
+3 -7
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@@ -1,12 +1,11 @@
.PHONY: bootstrap setup test lint fmt fmt-check tidy check docker publish \ .PHONY: bootstrap setup test lint fmt fmt-check tidy check docker hooks build \
hooks build run example-app run example-app
# Makefile targets are thin shims; the implementations live in script/ # Makefile targets are thin shims; the implementations live in script/
# per the scripts-to-rule-them-all pattern (see the Entrypoints section # per the scripts-to-rule-them-all pattern (see the Entrypoints section
# of README.md). tidy writes go.mod and go.sum as `go mod tidy` does, # of README.md). tidy writes go.mod and go.sum as `go mod tidy` does,
# which test checks. build and run are for working on the code by hand; # which test checks. build and run are for working on the code by hand;
# example-app checks the image with an app built on it; publish builds # example-app checks the image with an app built on it.
# the image on the Docker host and pushes it to the registry.
bootstrap: bootstrap:
@script/bootstrap @script/bootstrap
@@ -35,9 +34,6 @@ check:
docker: docker:
@script/docker @script/docker
publish:
@script/publish
hooks: hooks:
@script/install-precommit @script/install-precommit
README.md
+125 -140
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@@ -25,11 +25,11 @@ without an answer in time, `rproxy` passes the request to the app.
It protects against: It protects against:
- Scrapers that fetch every page of a site, all day. Each client gets a limit on - 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 requests and on bytes per minute, per hour and per day. The defaults leave
leave room for a person reading a site for hours. They catch a scraper that room for a person reading a site for hours. They catch a scraper that keeps up
keeps up one request every 2 seconds. A client that breaks a limit is banned: one request every 2 seconds. A client over a limit is refused and banned: for
for a while at first, for three times as long at each repeat, and permanently a while at first, for three times as long at each repeat, and permanently when
when it keeps at it. it keeps at it.
- Scanners that probe for secrets, such as `/.env` or `/.git/config`. The - Scanners that probe for secrets, such as `/.env` or `/.git/config`. The
default rule file bans such a client at its first probe, and its next request default rule file bans such a client at its first probe, and its next request
during the ban makes the ban permanent. Your own rules, or a list of trap during the ban makes the ban permanent. Your own rules, or a list of trap
@@ -68,9 +68,8 @@ Not built, and not planned:
### The image ### The image
The image is published at `git.eeqj.de/sneak/smallwebwaf`. You can also build it No image is published. Build it from a clone. `make docker` runs the tests and
from a clone. `make docker` runs the tests and the linter, then builds the the linter, then builds the image, tagged `smallwebwaf`.
image, tagged `smallwebwaf`.
```sh ```sh
git clone https://git.eeqj.de/sneak/smallwebwaf.git git clone https://git.eeqj.de/sneak/smallwebwaf.git
@@ -210,132 +209,128 @@ account, a key, a token or an alert destination stays off until you give one.
percentage is a whole number from 0 to 100. A path prefix starts with `/`. percentage is a whole number from 0 to 100. A path prefix starts with `/`.
- `off` switches a limit, a threshold or a timeout off where the table says a - `off` switches a limit, a threshold or a timeout off where the table says a
setting takes it. setting takes it.
- The byte limits and the byte anomaly thresholds count only body bytes: the
app's response bodies, the visitors' request bodies, or both, as
`SWW_BYTES_COUNT` says. Headers are never counted. What the visitor sent over
a WebSocket counts as request bytes, and what the app sent as response bytes.
- An invalid setting stops the process at start with one log line naming the - An invalid setting stops the process at start with one log line naming the
variable and what is wrong with the value. The settings in effect are logged variable and what is wrong with the value. The settings in effect are logged
on one line at start, with tokens, keys and webhook paths shown as `********`. on one line at start, with tokens, keys and webhook paths shown as `********`.
Every setting the code reads, with its default: Every setting the code reads, with its default:
| Variable | Default | What it does | | Variable | Default | What it does |
| ---------------------------------------- | ------------------------------------------------------------------------------ | --------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- | | ---------------------------------------- | ------------------------------------------------------------------------------ | ----------------------------------------------------------------------------------------------------------------------------------------------------------------- |
| `SWW_COMMAND` | `rproxy` | Which command the image runs, and its health check checks: `rproxy` or `discriminator`. | | `SWW_COMMAND` | `rproxy` | Which command the image runs, and its health check checks: `rproxy` or `discriminator`. |
| `SWRP_WAF_BACKEND` | required | `discriminator`'s URL, such as `http://discriminator:8080`. | | `SWRP_WAF_BACKEND` | required | `discriminator`'s URL, such as `http://discriminator:8080`. |
| `SWRP_UPSTREAM_URL` | `http://127.0.0.1:8081` | The app's URL: a scheme, a host and an optional port, nothing more. | | `SWRP_UPSTREAM_URL` | `http://127.0.0.1:8081` | The app's URL: a scheme, a host and an optional port, nothing more. |
| `SWRP_LISTEN_ADDR` | `:8080` | Where `rproxy` listens; leave the host part empty. | | `SWRP_LISTEN_ADDR` | `:8080` | Where `rproxy` listens; leave the host part empty. |
| `SWRP_TRUSTED_PROXIES` | `10.0.0.0/8,172.16.0.0/12,192.168.0.0/16` | The netblocks whose `X-Forwarded-For` `rproxy` believes; set but empty, it believes none. | | `SWRP_TRUSTED_PROXIES` | `10.0.0.0/8,172.16.0.0/12,192.168.0.0/16` | The netblocks whose `X-Forwarded-For` `rproxy` believes; set but empty, it believes none. |
| `SWRP_TIMEOUT_MS` | `2000` | How long `rproxy` waits for `discriminator`'s answer to a question and to a report, in milliseconds. | | `SWRP_TIMEOUT_MS` | `2000` | How long `rproxy` waits for `discriminator`'s answer to a question and to a report, in milliseconds. |
| `SWRP_DEFAULT_DISPOSITION` | `allow` | What `rproxy` does with a request when `discriminator` cannot be reached or does not answer in time: `allow` passes it to the app, `deny` answers `503`. | | `SWRP_DEFAULT_DISPOSITION` | `allow` | What `rproxy` does with a request when `discriminator` cannot be reached or does not answer in time: `allow` passes it to the app, `deny` answers `503`. |
| `SWRP_MAX_REQUEST_SIZE` | `100M` | The largest request body, a size or `off`; a larger one is answered `413`. | | `SWRP_MAX_REQUEST_SIZE` | `100M` | The largest request body, a size or `off`; a larger one is answered `413`. |
| `SWRP_MAX_RESPONSE_SIZE` | `1G` | The largest response body, a size or `off`; a larger one is answered `502`, or cut off once it has started. | | `SWRP_MAX_RESPONSE_SIZE` | `1G` | The largest response body, a size or `off`; a larger one is answered `502`, or cut off once it has started. |
| `SWRP_MAX_REQUEST_TIME_MS` | `60000` | 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. | | `SWRP_MAX_REQUEST_TIME_MS` | `60000` | How long the visitor may take to send its request line and headers, and then the whole request to reach the app, in milliseconds or `off`. |
| `SWRP_MAX_RESPONSE_TIME_MS` | `1800000` | How long the answer may take, from the end of the request to its last byte reaching the visitor, in milliseconds or `off`. | | `SWRP_MAX_RESPONSE_TIME_MS` | `1800000` | How long the answer may take, from the end of the request to its last byte reaching the visitor, in milliseconds or `off`. |
| `SWW_LISTEN_ADDR` | `:8080` | Where `discriminator` listens; leave the host part empty. | | `SWW_LISTEN_ADDR` | `:8080` | Where `discriminator` listens; leave the host part empty. |
| `SWW_INSTANCE_NAME` | the container's host name | The name in every line `discriminator` logs, and in every alert and metric, such as `fsn1/discriminator`. | | `SWW_INSTANCE_NAME` | the container's host name | The name in every line `discriminator` logs, and in every alert and metric, such as `fsn1/discriminator`. |
| `SWW_MODE` | `enforce` | `observe` refuses nothing and makes no ban; each log line says what `enforce` would have done. | | `SWW_MODE` | `enforce` | `observe` refuses nothing and makes no ban; each log line says what `enforce` would have done. |
| `SWW_IPV6_GROUP_PREFIX` | `64` | The prefix length of the IPv6 netblock that counts as one client, from 32 to 128. | | `SWW_IPV6_GROUP_PREFIX` | `64` | The prefix length of the IPv6 netblock that counts as one client, from 32 to 128. |
| `SWW_MAX_TRACKED_CLIENTS` | `20000` | The most clients kept, in memory and in `clients.json`; the least recently seen is dropped first. | | `SWW_MAX_TRACKED_CLIENTS` | `20000` | The most clients kept, in memory and in `clients.json`; the least recently seen is dropped first. |
| `SWW_MAX_BANS` | `5000` | The most bans `discriminator` keeps of its own; bans an admin made do not count. | | `SWW_MAX_BANS` | `5000` | The most bans `discriminator` keeps of its own; bans an admin made do not count. |
| `SWW_ALLOW_NETS` | empty | Netblocks whose clients skip every check, such as your monitoring. | | `SWW_ALLOW_NETS` | empty | Netblocks whose clients skip every check, such as your monitoring. |
| `SWW_RATE_LIMIT_EXEMPT_NETS` | empty | Netblocks whose clients the request and byte limits neither count nor refuse. | | `SWW_RATE_LIMIT_EXEMPT_NETS` | empty | Netblocks whose clients the request and byte limits neither count nor refuse. |
| `SWW_DENY_NETS` | empty | Netblocks whose clients are refused. | | `SWW_DENY_NETS` | empty | Netblocks whose clients are refused. |
| `SWW_RATE_LIMIT_PER_MINUTE` | `120` | The most requests a client may make in a minute, a count or `off`; the next request is refused and bans the client. | | `SWW_RATE_LIMIT_PER_MINUTE` | `120` | The most requests a client may make in a minute, a count or `off`; one more bans it. |
| `SWW_RATE_LIMIT_PER_HOUR` | `1500` | The most requests a client may make in an hour, a count or `off`; the next request is refused and bans the client. | | `SWW_RATE_LIMIT_PER_HOUR` | `1500` | The most requests a client may make in an hour, a count or `off`; one more bans it. |
| `SWW_RATE_LIMIT_PER_DAY` | `6000` | The most requests a client may make in a day, a count or `off`; the next request is refused and bans the client. | | `SWW_RATE_LIMIT_PER_DAY` | `6000` | The most requests a client may make in a day, a count or `off`; one more bans it. |
| `SWW_RATE_LIMIT_EXEMPT_PATHS` | empty | Path prefixes whose requests the request and byte limits neither count nor refuse, such as `/assets/`. | | `SWW_RATE_LIMIT_EXEMPT_PATHS` | empty | Path prefixes whose requests the request and byte limits neither count nor refuse, such as `/assets/`. |
| `SWW_BYTES_LIMIT_PER_MINUTE` | `off` | The most bytes counted for a client in a minute, a size or `off`: response bodies, request bodies or both, as `SWW_BYTES_COUNT` says. The request that passes the limit is not cut off, and the client is banned when its response ends. | | `SWW_BYTES_LIMIT_PER_MINUTE` | `off` | The most bytes a client's requests may carry in a minute, a size or `off`; the request that takes a client past any byte limit bans it. |
| `SWW_BYTES_LIMIT_PER_HOUR` | `50G` | The most bytes counted for a client in an hour, a size or `off`: response bodies, request bodies or both, as `SWW_BYTES_COUNT` says. The request that passes the limit is not cut off, and the client is banned when its response ends. | | `SWW_BYTES_LIMIT_PER_HOUR` | `50G` | The most bytes a client's requests may carry in an hour, a size or `off`. |
| `SWW_BYTES_LIMIT_PER_DAY` | `100G` | The most bytes counted for a client in a day, a size or `off`: response bodies, request bodies or both, as `SWW_BYTES_COUNT` says. The request that passes the limit is not cut off, and the client is banned when its response ends. | | `SWW_BYTES_LIMIT_PER_DAY` | `100G` | The most bytes a client's requests may carry in a day, a size or `off`. |
| `SWW_BYTES_COUNT` | `both` | What the byte limits and the byte anomaly thresholds count: `response`, the app's response bodies; `request`, the visitors' request bodies; or `both`. What the visitor sent over a WebSocket counts as request bytes, and what the app sent as response bytes. | | `SWW_BYTES_COUNT` | `both` | Which body bytes the byte limits count: `response`, `request` or `both`. |
| `SWW_ERROR_BURST_THRESHOLD` | `30` | The most refusals a client may get in a minute from a rule file, a trap path or the Core Rule Set, a count or `off`. The next one bans the client. | | `SWW_ERROR_BURST_THRESHOLD` | `30` | The most refusals by a rule file, a trap path or the Core Rule Set a client may get in a minute, a count or `off`; one more bans it. |
| `SWW_BAN_RESPONSE` | `403` | How a refused client is answered: `403`, `429` or `close`, which drops the connection. | | `SWW_BAN_RESPONSE` | `403` | How a refused client is answered: `403`, `429` or `close`, which drops the connection. |
| `SWW_LIMIT_BAN_DURATION` | `1h` | The ban for a first broken limit. | | `SWW_LIMIT_BAN_DURATION` | `1h` | The ban for a first broken limit. |
| `SWW_LIMIT_BAN_REPEAT_WINDOW` | `24h` | A limit broken again within this time after the last such ban ended gets a ban three times as long. | | `SWW_LIMIT_BAN_REPEAT_WINDOW` | `24h` | A limit broken again within this time after the last such ban ended gets a ban three times as long. |
| `SWW_MAX_BAN_DURATION` | `7d` | A ban for a broken limit that would be longer than this is permanent instead. | | `SWW_MAX_BAN_DURATION` | `7d` | A ban for a broken limit that would be longer than this is permanent instead. |
| `SWW_ATTACK_BAN_DURATION` | `7d` | The ban for a first clear sign of attack: a `ban` rule or a trap path. | | `SWW_ATTACK_BAN_DURATION` | `7d` | The ban for a first clear sign of attack: a `ban` rule or a trap path. |
| `SWW_BAN_SCOPE_V4_PREFIX` | `32` | The prefix length of the netblock a ban on an IPv4 client covers, from 0 to 32. | | `SWW_BAN_SCOPE_V4_PREFIX` | `32` | The prefix length of the netblock a ban on an IPv4 client covers, from 0 to 32. |
| `SWW_LOOKUP_SOURCE` | `geojs` | Where each client's AS number and country come from: `geojs` (a web service), `file` (a local database) or `off`. | | `SWW_LOOKUP_SOURCE` | `geojs` | Where each client's AS number and country come from: `geojs`, a web service, `file`, or `off`. |
| `SWW_LOOKUP_DB_PATH` | empty | The IPinfo Lite database file, in its `.mmdb` form, read while the source is `file`. | | `SWW_LOOKUP_DB_PATH` | empty | The IPinfo Lite database file, in its `.mmdb` form, read while the source is `file`. |
| `SWW_LOOKUP_TIMEOUT` | `800ms` | How long a request waits for its client's first GeoJS answer when a setting needs it, and how long a request to GeoJS may take. | | `SWW_LOOKUP_TIMEOUT` | `800ms` | How long a request waits for its client's first GeoJS answer when a setting needs it, and how long a request to GeoJS may take. |
| `SWW_ADD_LOOKUP_HEADERS` | `false` | `true` passes the app the client's AS number and country in `X-Client-ASN` and `X-Client-Country`. | | `SWW_ADD_LOOKUP_HEADERS` | `false` | `true` passes the app the client's AS number and country in `X-Client-ASN` and `X-Client-Country`. |
| `SWW_DENIED_COUNTRIES` | empty | Countries whose clients are refused, such as `cn,ru`. | | `SWW_DENIED_COUNTRIES` | empty | Countries whose clients are refused, such as `cn,ru`. |
| `SWW_EXCLUSIVELY_ALLOWED_COUNTRIES` | empty | When set, the only countries whose clients get through; a client the lookup cannot place is refused too. | | `SWW_EXCLUSIVELY_ALLOWED_COUNTRIES` | empty | When set, the only countries whose clients get through; a client the lookup cannot place is refused too. |
| `SWW_ASN_LIMIT_PERCENT` | empty | AS numbers whose clients get a percentage of every request and byte limit, such as `AS14061:50,AS16276:25`. | | `SWW_ASN_LIMIT_PERCENT` | empty | AS numbers whose clients get a percentage of every request and byte limit, such as `AS14061:50,AS16276:25`. |
| `SWW_COUNTRY_LIMIT_PERCENT` | empty | The same by country, such as `cn:25`. | | `SWW_COUNTRY_LIMIT_PERCENT` | empty | The same by country, such as `cn:25`. |
| `SWW_ASN_BYTES_PERCENT` | empty | A percentage of the byte limits alone for the AS numbers listed, in place of their `SWW_ASN_LIMIT_PERCENT`. | | `SWW_ASN_BYTES_PERCENT` | empty | A percentage of the byte limits alone for the AS numbers listed, in place of their `SWW_ASN_LIMIT_PERCENT`. |
| `SWW_COUNTRY_BYTES_PERCENT` | empty | A percentage of the byte limits alone for the countries listed, in place of their `SWW_COUNTRY_LIMIT_PERCENT`. | | `SWW_COUNTRY_BYTES_PERCENT` | empty | A percentage of the byte limits alone for the countries listed, in place of their `SWW_COUNTRY_LIMIT_PERCENT`. |
| `SWW_UNKNOWN_LIMIT_PERCENT` | `100` | The percentage of every limit a client without a country gets. | | `SWW_UNKNOWN_LIMIT_PERCENT` | `100` | The percentage of every limit a client without a country gets. |
| `SWW_ASN_LIMIT_PERCENT_URL` | unset | The URL of a text file of `AS<number>:<percent>` lines, fetched like a blocklist; where it and `SWW_ASN_LIMIT_PERCENT` both give a percentage, the lower applies. | | `SWW_ASN_LIMIT_PERCENT_URL` | unset | The URL of a text file of `AS<number>:<percent>` lines, fetched like a blocklist; where it and `SWW_ASN_LIMIT_PERCENT` both give a percentage, the lower applies. |
| `SWW_RULES_DIR` | `/etc/sww/rules.d` | The directory of the rule files, read at start and again when a file there changes. | | `SWW_RULES_DIR` | `/etc/sww/rules.d` | The directory of the rule files, read at start and again when a file there changes. |
| `SWW_RULES_ENABLED` | `true` | `false` reads no rule file. | | `SWW_RULES_ENABLED` | `true` | `false` reads no rule file. |
| `SWW_TRAP_PATHS` | empty | Paths only scanners ask for, such as `/wp-login.php,/xmlrpc.php`; a request for one bans the client. | | `SWW_TRAP_PATHS` | empty | Paths only scanners ask for, such as `/wp-login.php,/xmlrpc.php`; a request for one bans the client. |
| `SWW_WAF_MODE` | `block` | What the Core Rule Set does with a match: `block` refuses it with `403`, `detect` only logs and alerts it, `off` runs no rule. | | `SWW_WAF_MODE` | `block` | What the Core Rule Set does with a match: `block` refuses it with `403`, `detect` only logs and alerts it, `off` runs no rule. |
| `SWW_WAF_PARANOIA_LEVEL` | `1` | The Core Rule Set's paranoia level, from 1 to 4; each level up finds more attacks and takes more ordinary requests for attacks. | | `SWW_WAF_PARANOIA_LEVEL` | `1` | The Core Rule Set's paranoia level, from 1 to 4; each level up finds more attacks and takes more ordinary requests for attacks. |
| `SWW_WAF_ANOMALY_THRESHOLD` | `5` | The Core Rule Set score at which a request is a match, a whole number or `off`; one critical rule scores 5. | | `SWW_WAF_ANOMALY_THRESHOLD` | `5` | The Core Rule Set score at which a request is a match, a whole number or `off`; one critical rule scores 5. |
| `SWW_WAF_DISABLED_RULES` | `920340,920420,920440,920640,930130,930140` | Core Rule Set rule ids switched off; a list you give replaces the default, so repeat these six to keep them off. | | `SWW_WAF_DISABLED_RULES` | `920340,920420,920440,920640,930130,930140` | Core Rule Set rule ids switched off; a list you give replaces the default, so repeat these six to keep them off. |
| `SWW_WAF_EXEMPT_PATHS` | empty | Path prefixes the Core Rule Set does not inspect. | | `SWW_WAF_EXEMPT_PATHS` | empty | Path prefixes the Core Rule Set does not inspect. |
| `SWW_WAF_BODY_LIMIT` | `off` | How much of a request body the Core Rule Set reads, a size up to `64K`; `off` reads none. | | `SWW_WAF_BODY_LIMIT` | `off` | How much of a request body the Core Rule Set reads, a size up to `64K`; `off` reads none. |
| `SWW_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_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_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`. | | `SWW_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`. |
| `SWW_BLOCKLIST_REFRESH` | `24h` | How long after a list was last tried it is fetched again, `1h` or more. | | `SWW_BLOCKLIST_REFRESH` | `24h` | How long after a list was last tried it is fetched again, `1h` or more. |
| `SWW_BLOCKLIST_ACTION` | `deny` | What a client on a blocklist gets: `deny`, `limit:<percent>` of every limit, or `log`. | | `SWW_BLOCKLIST_ACTION` | `deny` | What a client on a blocklist gets: `deny`, `limit:<percent>` of every limit, or `log`. |
| `SWW_DNSBL_ZONES` | empty | DNS blocklists asked about each new client in the background, such as `dnsbl.dronebl.org`. | | `SWW_DNSBL_ZONES` | empty | DNS blocklists asked about each new client in the background, such as `dnsbl.dronebl.org`. |
| `SWW_DNSBL_RESOLVER` | unset | The resolver the zones are asked through, an IP address with an optional port; unset, the host's resolver is used. | | `SWW_DNSBL_RESOLVER` | unset | The resolver the zones are asked through, an IP address with an optional port; unset, the host's resolver is used. |
| `SWW_ABUSEIPDB_KEY` | unset | The key of your AbuseIPDB account; set, a client that has committed an offence is checked in the background. | | `SWW_ABUSEIPDB_KEY` | unset | The key of your AbuseIPDB account; set, a client that has committed an offence is checked in the background. |
| `SWW_ABUSEIPDB_MIN_SCORE` | `75` | The least AbuseIPDB abuse confidence score, from 0 to 100, that is a hit. | | `SWW_ABUSEIPDB_MIN_SCORE` | `75` | The least AbuseIPDB abuse confidence score, from 0 to 100, that is a hit. |
| `SWW_ABUSEIPDB_DAILY_BUDGET` | `900` | The most AbuseIPDB checks made in a day. | | `SWW_ABUSEIPDB_DAILY_BUDGET` | `900` | The most AbuseIPDB checks made in a day. |
| `SWW_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_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_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_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_REPUTATION_ACTION` | `limit:25` | What a client listed by a DNS blocklist, or scored a hit by AbuseIPDB, gets: `deny`, `limit:<percent>` or `log`. | | `SWW_REPUTATION_ACTION` | `limit:25` | What a client listed by a DNS blocklist, or scored a hit by AbuseIPDB, gets: `deny`, `limit:<percent>` or `log`. |
| `SWW_REPUTATION_CACHE_TTL` | `24h` | How long a DNS blocklist verdict or an AbuseIPDB score is used. | | `SWW_REPUTATION_CACHE_TTL` | `24h` | How long a DNS blocklist verdict or an AbuseIPDB score is used. |
| `SWW_REPUTATION_TIMEOUT` | `2s` | How long a DNS blocklist query or an AbuseIPDB check may take. | | `SWW_REPUTATION_TIMEOUT` | `2s` | How long a DNS blocklist query or an AbuseIPDB check may take. |
| `SWW_STATE_DIR` | `/var/lib/sww` | The directory of the state files, an absolute path. | | `SWW_STATE_DIR` | `/var/lib/sww` | The directory of the state files, an absolute path. |
| `SWW_STATE_WRITE_DELAY` | `10s` | How long `bans.json` waits to be written after a ban is made, lifted or made permanent. | | `SWW_STATE_WRITE_DELAY` | `10s` | How long `bans.json` waits to be written after a ban is made, lifted or made permanent. |
| `SWW_STATE_COUNTER_INTERVAL` | `15m` | How often every state file is written. | | `SWW_STATE_COUNTER_INTERVAL` | `15m` | How often every state file is written. |
| `SWW_LOG_LEVEL` | `info` | The least severe of `discriminator`'s own messages that are written: `debug`, `info`, `warn` or `error`; request lines are always written. | | `SWW_LOG_LEVEL` | `info` | The least severe of `discriminator`'s own messages that are written: `debug`, `info`, `warn` or `error`; request lines are always written. |
| `SWW_LOG_REQUEST_HEADERS` | `accept,accept-language,accept-encoding,content-type,origin,range` | The request headers whose values the request log records; `Authorization` and `Cookie` are never recorded. | | `SWW_LOG_REQUEST_HEADERS` | `accept,accept-language,accept-encoding,content-type,origin,range` | The request headers whose values the request log records; `Authorization` and `Cookie` are never recorded. |
| `SWW_LOG_REMOTE_URL` | unset | A syslog server that also gets every line `discriminator` writes: `syslog+udp://`, `syslog+tcp://` or `syslog+tls://` with a host and a port. | | `SWW_LOG_REMOTE_URL` | unset | A syslog server that also gets every line `discriminator` writes: `syslog+udp://`, `syslog+tcp://` or `syslog+tls://` with a host and a port. |
| `SWW_LOG_REMOTE_TLS_CA_FILE` | unset | A file of PEM certificates a `syslog+tls` server's certificate must chain to, instead of the host's own. | | `SWW_LOG_REMOTE_TLS_CA_FILE` | unset | A file of PEM certificates a `syslog+tls` server's certificate must chain to, instead of the host's own. |
| `SWW_LOG_REMOTE_BUFFER` | `10000` | The most lines held while they wait to be sent; past it, the oldest is dropped. | | `SWW_LOG_REMOTE_BUFFER` | `10000` | The most lines held while they wait to be sent; past it, the oldest is dropped. |
| `SWW_LOG_REMOTE_FACILITY` | `local0` | The syslog facility of each record sent. | | `SWW_LOG_REMOTE_FACILITY` | `local0` | The syslog facility of each record sent. |
| `SWW_LOG_REMOTE_APP_NAME` | `SWW_INSTANCE_NAME` | The app name in each syslog record, 1 to 48 printable ASCII characters without a space. | | `SWW_LOG_REMOTE_APP_NAME` | `SWW_INSTANCE_NAME` | The app name in each syslog record, 1 to 48 printable ASCII characters without a space. |
| `SWW_ADMIN_TOKEN` | unset | The bearer token for the ban and client endpoints, at least 32 characters; unset, they answer `404`. | | `SWW_ADMIN_TOKEN` | unset | The bearer token for the ban and client endpoints, at least 32 characters; unset, they answer `404`. |
| `SWW_METRICS_TOKEN` | unset | The bearer token for `/_sww/metrics`, at least 32 characters; unset, the metrics are off. | | `SWW_METRICS_TOKEN` | unset | The bearer token for `/_sww/metrics`, at least 32 characters; unset, the metrics are off. |
| `SWW_METRICS_TOP_N` | `50` | How many AS numbers and how many countries get metric series of their own; the rest are summed as `other`. | | `SWW_METRICS_TOP_N` | `50` | How many AS numbers and how many countries get metric series of their own; the rest are summed as `other`. |
| `SWW_ALERT_WEBHOOK_URL` | unset | A webhook each alert is posted to as a JSON object. | | `SWW_ALERT_WEBHOOK_URL` | unset | A webhook each alert is posted to as a JSON object. |
| `SWW_ALERT_WEBHOOK_HEADERS` | empty | Headers sent with each post, a list of `Name:value`, such as `Authorization:Bearer <token>`. | | `SWW_ALERT_WEBHOOK_HEADERS` | empty | Headers sent with each post, a list of `Name:value`, such as `Authorization:Bearer <token>`. |
| `SWW_ALERT_SLACK_WEBHOOK_URL` | unset | A Slack incoming webhook each alert is posted to as a message. | | `SWW_ALERT_SLACK_WEBHOOK_URL` | unset | A Slack incoming webhook each alert is posted to as a message. |
| `SWW_ALERT_NTFY_URL` | unset | An ntfy topic each alert is published to, as its full URL, such as `https://ntfy.sh/my-alerts`. | | `SWW_ALERT_NTFY_URL` | unset | An ntfy topic each alert is published to, as its full URL, such as `https://ntfy.sh/my-alerts`. |
| `SWW_ALERT_NTFY_TOKEN` | unset | An ntfy access token sent with each alert. | | `SWW_ALERT_NTFY_TOKEN` | unset | An ntfy access token sent with each alert. |
| `SWW_ALERT_EVENTS` | `ban,permanent_ban,waf_block,anomaly,reputation_hit,source_failure,file_error` | The events alerts are sent for; the hourly `summary` is sent whatever it says. | | `SWW_ALERT_EVENTS` | `ban,permanent_ban,waf_block,anomaly,reputation_hit,source_failure,file_error` | The events alerts are sent for; the hourly `summary` is sent whatever it says. |
| `SWW_ALERT_COOLDOWN` | `15m` | How long after an alert its repeats are held back and counted, a duration or `off`. | | `SWW_ALERT_COOLDOWN` | `15m` | How long after an alert its repeats are held back and counted, a duration or `off`. |
| `SWW_ALERT_MAX_PER_HOUR` | `60` | The most alerts sent in an hour, a number or `off`; the rest are counted in the hour's `summary`. | | `SWW_ALERT_MAX_PER_HOUR` | `60` | The most alerts sent in an hour, a number or `off`; the rest are counted in the hour's `summary`. |
| `SWW_ANOMALY_CLIENT_REQUESTS_PER_MINUTE` | `off` | Alert when one client makes more requests than this in a minute, a count. | | `SWW_ANOMALY_CLIENT_REQUESTS_PER_MINUTE` | `off` | Alert when one client makes more requests than this in a minute, a count. |
| `SWW_ANOMALY_CLIENT_REQUESTS_PER_HOUR` | `off` | Alert when one client makes more requests than this in an hour, a count. | | `SWW_ANOMALY_CLIENT_REQUESTS_PER_HOUR` | `off` | Alert when one client makes more requests than this in an hour, a count. |
| `SWW_ANOMALY_CLIENT_BYTES_PER_MINUTE` | `off` | Alert when more than this many bytes, as `SWW_BYTES_COUNT` counts them, are counted for one client in a minute, a size. | | `SWW_ANOMALY_CLIENT_BYTES_PER_MINUTE` | `off` | Alert when one client's requests carry more bytes than this in a minute, a size. |
| `SWW_ANOMALY_CLIENT_BYTES_PER_HOUR` | `off` | Alert when more than this many bytes, as `SWW_BYTES_COUNT` counts them, are counted for one client in an hour, a size. | | `SWW_ANOMALY_CLIENT_BYTES_PER_HOUR` | `off` | Alert when one client's requests carry more bytes than this in an hour, a size. |
| `SWW_ANOMALY_NET_REQUESTS_PER_MINUTE` | `off` | Alert when the netblock around a client makes more requests than this in a minute, a count. | | `SWW_ANOMALY_NET_REQUESTS_PER_MINUTE` | `off` | Alert when the netblock around a client makes more requests than this in a minute, a count. |
| `SWW_ANOMALY_NET_REQUESTS_PER_HOUR` | `off` | Alert when the netblock around a client makes more requests than this in an hour, a count. | | `SWW_ANOMALY_NET_REQUESTS_PER_HOUR` | `off` | Alert when the netblock around a client makes more requests than this in an hour, a count. |
| `SWW_ANOMALY_NET_BYTES_PER_MINUTE` | `off` | Alert when more than this many bytes, as `SWW_BYTES_COUNT` counts them, are counted for the netblock around a client in a minute, a size. | | `SWW_ANOMALY_NET_BYTES_PER_MINUTE` | `off` | Alert when the netblock around a client carries more bytes than this in a minute, a size. |
| `SWW_ANOMALY_NET_BYTES_PER_HOUR` | `off` | Alert when more than this many bytes, as `SWW_BYTES_COUNT` counts them, are counted for the netblock around a client in an hour, a size. | | `SWW_ANOMALY_NET_BYTES_PER_HOUR` | `off` | Alert when the netblock around a client carries more bytes than this in an hour, a size. |
| `SWW_ANOMALY_NET_V4_PREFIX` | `24` | The prefix length of the netblock around an IPv4 client that the `SWW_ANOMALY_NET_` thresholds count, from 0 to 32. | | `SWW_ANOMALY_NET_V4_PREFIX` | `24` | The prefix length of the netblock around an IPv4 client that the `SWW_ANOMALY_NET_` thresholds count, from 0 to 32. |
| `SWW_ANOMALY_NET_V6_PREFIX` | `48` | The prefix length of the netblock around an IPv6 client that the `SWW_ANOMALY_NET_` thresholds count, from 0 to 128. | | `SWW_ANOMALY_NET_V6_PREFIX` | `48` | The prefix length of the netblock around an IPv6 client that the `SWW_ANOMALY_NET_` thresholds count, from 0 to 128. |
| `SWW_ANOMALY_ASN_REQUESTS_PER_MINUTE` | `off` | Alert when one AS number makes more requests than this in a minute, a count. | | `SWW_ANOMALY_ASN_REQUESTS_PER_MINUTE` | `off` | Alert when one AS number makes more requests than this in a minute, a count. |
| `SWW_ANOMALY_ASN_REQUESTS_PER_HOUR` | `off` | Alert when one AS number makes more requests than this in an hour, a count. | | `SWW_ANOMALY_ASN_REQUESTS_PER_HOUR` | `off` | Alert when one AS number makes more requests than this in an hour, a count. |
| `SWW_ANOMALY_ASN_BYTES_PER_MINUTE` | `off` | Alert when more than this many bytes, as `SWW_BYTES_COUNT` counts them, are counted for one AS number in a minute, a size. | | `SWW_ANOMALY_ASN_BYTES_PER_MINUTE` | `off` | Alert when one AS number carries more bytes than this in a minute, a size. |
| `SWW_ANOMALY_ASN_BYTES_PER_HOUR` | `off` | Alert when more than this many bytes, as `SWW_BYTES_COUNT` counts them, are counted for one AS number in an hour, a size. | | `SWW_ANOMALY_ASN_BYTES_PER_HOUR` | `off` | Alert when one AS number carries more bytes than this in an hour, a size. |
| `SWW_ANOMALY_TOTAL_REQUESTS_PER_MINUTE` | `off` | Alert when the whole service gets more requests than this in a minute, a count. | | `SWW_ANOMALY_TOTAL_REQUESTS_PER_MINUTE` | `off` | Alert when the whole service gets more requests than this in a minute, a count. |
| `SWW_ANOMALY_TOTAL_REQUESTS_PER_HOUR` | `off` | Alert when the whole service gets more requests than this in an hour, a count. | | `SWW_ANOMALY_TOTAL_REQUESTS_PER_HOUR` | `off` | Alert when the whole service gets more requests than this in an hour, a count. |
| `SWW_ANOMALY_TOTAL_BYTES_PER_MINUTE` | `off` | Alert when more than this many bytes, as `SWW_BYTES_COUNT` counts them, are counted for the whole service in a minute, a size. | | `SWW_ANOMALY_TOTAL_BYTES_PER_MINUTE` | `off` | Alert when the whole service carries more bytes than this in a minute, a size. |
| `SWW_ANOMALY_TOTAL_BYTES_PER_HOUR` | `off` | Alert when more than this many bytes, as `SWW_BYTES_COUNT` counts them, are counted for the whole service in an hour, a size. | | `SWW_ANOMALY_TOTAL_BYTES_PER_HOUR` | `off` | Alert when the whole service carries more bytes than this in an hour, a size. |
| `SWW_WATCH_NETS` | empty | Named netblocks the `SWW_WATCH_` thresholds count each as a whole, such as `office=203.0.113.0/24,scraper-x=198.51.100.0/22`. | | `SWW_WATCH_NETS` | empty | Named netblocks the `SWW_WATCH_` thresholds count each as a whole, such as `office=203.0.113.0/24,scraper-x=198.51.100.0/22`. |
| `SWW_WATCH_REQUESTS_PER_MINUTE` | `off` | Alert when a watched netblock makes more requests than this in a minute, a count. | | `SWW_WATCH_REQUESTS_PER_MINUTE` | `off` | Alert when a watched netblock makes more requests than this in a minute, a count. |
| `SWW_WATCH_REQUESTS_PER_HOUR` | `off` | Alert when a watched netblock makes more requests than this in an hour, a count. | | `SWW_WATCH_REQUESTS_PER_HOUR` | `off` | Alert when a watched netblock makes more requests than this in an hour, a count. |
| `SWW_WATCH_BYTES_PER_MINUTE` | `off` | Alert when more than this many bytes, as `SWW_BYTES_COUNT` counts them, are counted for a watched netblock in a minute, a size. | | `SWW_WATCH_BYTES_PER_MINUTE` | `off` | Alert when a watched netblock carries more bytes than this in a minute, a size. |
| `SWW_WATCH_BYTES_PER_HOUR` | `off` | Alert when more than this many bytes, as `SWW_BYTES_COUNT` counts them, are counted for a watched netblock in an hour, a size. | | `SWW_WATCH_BYTES_PER_HOUR` | `off` | Alert when a watched netblock carries more bytes than this in an hour, a size. |
[`docs/settings.md`](docs/settings.md) gives the values each setting takes in [`docs/settings.md`](docs/settings.md) gives the values each setting takes in
full, and the limits that are fixed rather than settings. full, and the limits that are fixed rather than settings.
@@ -529,9 +524,8 @@ of the request reaches the app.
14. The request is passed to the app, streaming. 14. The request is passed to the app, streaming.
15. After the answer, `rproxy` sends `discriminator` a report with the status 15. After the answer, `rproxy` sends `discriminator` a report with the status
and the body bytes each way. For an allowed request, `discriminator` counts and the bytes each way. For an allowed request, `discriminator` counts the
the bytes `SWW_BYTES_COUNT` names toward the byte limits, bans the client if bytes toward the byte limits and adds the request to the client's history.
they take it past one, and adds the request to the client's history.
A refused visitor is answered with `SWW_BAN_RESPONSE`. A `block` rule or a Core A refused visitor is answered with `SWW_BAN_RESPONSE`. A `block` rule or a Core
Rule Set match answers `403` and bans nobody, since the Core Rule Set has false Rule Set match answers `403` and bans nobody, since the Core Rule Set has false
@@ -671,15 +665,6 @@ on the host.
`make check`. `make check`.
- `script/docker`: builds the image, whose build runs the tests and the linter - `script/docker`: builds the image, whose build runs the tests and the linter
first. `make docker`. first. `make docker`.
- `script/publish`: runs `script/docker`, whose build happens on the Docker host
named by `DOCKER_HOST` (`ssh://root@fsn1app1` unless set). It then pushes the
image to `PUBLISH_IMAGE` (`git.eeqj.de/sneak/smallwebwaf` unless set). It
refuses a working tree with uncommitted changes. `make publish`. It pushes
four tags:
- the UTC date as `YYYY-MM-DD`;
- the short commit hash;
- the branch name;
- `latest`.
- `script/cibuild`: what CI runs: `script/bootstrap`, `script/check`, then the - `script/cibuild`: what CI runs: `script/bootstrap`, `script/check`, then the
image build. image build.
- `script/precommit`: run by the git pre-commit hook; runs `script/check`. - `script/precommit`: run by the git pre-commit hook; runs `script/check`.
SPEC.md
+39 -53
View File
@@ -22,8 +22,8 @@ to them.
key or a token stays off until the operator supplies it. key or a token stays off until the operator supplies it.
- It keeps a site answering while the part that decides is down, slow or - It keeps a site answering while the part that decides is down, slow or
restarting (see "Without an answer from `discriminator`"). restarting (see "Without an answer from `discriminator`").
- It limits each client's requests and body bytes per minute, hour and day. It - It limits each client's requests and bytes per minute, hour and day. It bounds
bounds the size and duration of every request and answer. It detects attacks. the size and duration of every request and answer. It detects attacks.
- It bans abusers: briefly at first, for seven days on a clear sign of attack, - It bans abusers: briefly at first, for seven days on a clear sign of attack,
and permanently when they keep at it. and permanently when they keep at it.
- It looks up each client's AS number and country. It can refuse whole countries - It looks up each client's AS number and country. It can refuse whole countries
@@ -124,9 +124,7 @@ to them.
step that produces a final answer ends the checks. Step 15 runs for each request step that produces a final answer ends the checks. Step 15 runs for each request
`discriminator` answers with `allow`, `deny` or `close`. `rproxy`'s size and `discriminator` answers with `allow`, `deny` or `close`. `rproxy`'s size and
time limits apply to the whole exchange. Each step names the section that holds time limits apply to the whole exchange. Each step names the section that holds
its rules. A step that names a heuristic in parentheses runs that heuristic. The its rules.
request log's `heuristic` field gives that name. `refusal_limit` and
`byte_limits` give theirs in `after_answer_heuristic` instead.
1. `GET /_sww/healthz` is answered at once by `rproxy`, before any check, so a 1. `GET /_sww/healthz` is answered at once by `rproxy`, before any check, so a
health checker never needs an exemption and is never refused. health checker never needs an exemption and is never refused.
@@ -144,9 +142,9 @@ request log's `heuristic` field gives that name. `refusal_limit` and
around its address, a /64 by default, since one abuser usually controls a 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. whole /64. A client is therefore one IPv4 address or one IPv6 group.
3. The static lists. A client in `SWW_ALLOW_NETS` skips steps 4 to 12, the byte 3. The static lists. A client in `SWW_ALLOW_NETS` skips steps 4 to 12, the byte
limits and the error burst. A client in `SWW_DENY_NETS` is refused limits and the error burst. A client in `SWW_DENY_NETS` is refused; a client
(`deny_nets`); a client in both lists is let through. in both lists is let through.
4. Bans. A client under a ban is refused (`active_ban`; see "Bans"). 4. Bans. A client under a ban is refused (see "Bans").
5. The lookup, unless `SWW_LOOKUP_SOURCE` is `off` (see "Lookup of AS number and 5. The lookup, unless `SWW_LOOKUP_SOURCE` is `off` (see "Lookup of AS number and
country"). The request goes on at once. It waits for the first GeoJS answer, country"). The request goes on at once. It waits for the first GeoJS answer,
up to `SWW_LOOKUP_TIMEOUT`, only when one of these needs it: up to `SWW_LOOKUP_TIMEOUT`, only when one of these needs it:
@@ -156,25 +154,21 @@ request log's `heuristic` field gives that name. `refusal_limit` and
A request that ends before the answer comes is logged without it. A request that ends before the answer comes is logged without it.
6. The country lists (`countries`; see "Country lists"). 6. The country lists (see "Country lists").
7. The reputation sources (see "Reputation"), in this order: 7. The reputation sources (see "Reputation"). A client on a fetched blocklist
- A client on a fetched blocklist gets `SWW_BLOCKLIST_ACTION` gets `SWW_BLOCKLIST_ACTION`. A client on the CrowdSec decision list is
(`blocklists`). banned. A client listed by a DNS blocklist, or scored at least
- A client on the CrowdSec decision list is banned (`crowdsec`). `SWW_ABUSEIPDB_MIN_SCORE` by AbuseIPDB, gets `SWW_REPUTATION_ACTION`.
- A client listed by a DNS blocklist gets `SWW_REPUTATION_ACTION` (`dnsbl`).
- A client scored at least `SWW_ABUSEIPDB_MIN_SCORE` by AbuseIPDB gets
`SWW_REPUTATION_ACTION` (`abuseipdb`).
8. The client's limit percentage (see "Biased thresholds"). 8. The client's limit percentage (see "Biased thresholds").
9. Rate limiting (`rate_limits`; see "Request rate limits, per client"). A 9. Rate limiting (see "Request rate limits, per client"). A request over a limit
request over a limit times the percentage is refused and bans the client. times the percentage is refused and bans the client.
10. The trap paths (`trap_paths`; see "Attack detection"). A request for one is 10. The trap paths (see "Attack detection"). A request for one is refused and
refused and bans the client. bans the client.
11. The rule files (`rule_files`; see "Rule files"). Matching stops at the first 11. The rule files (see "Rule files"). Matching stops at the first rule that
rule that refuses. refuses.
12. The header limits (`header_limits`; see "Answering in time"), and then the 12. The header limits (see "Answering in time"), and then the Core Rule Set (see
Core Rule Set (`core_rule_set`; see "Attack detection"). A Core Rule Set "Attack detection"). A Core Rule Set match is refused with `403` while
match is refused with `403` while `SWW_WAF_MODE` is `block`, and only logged `SWW_WAF_MODE` is `block`, and only logged and alerted while it is `detect`.
and alerted while it is `detect`.
13. A path under `/_sww/` is answered `404`, so that the app never sees that 13. A path under `/_sww/` is answered `404`, so that the app never sees that
prefix. prefix.
14. `rproxy` passes the request to `SWRP_UPSTREAM_URL`, streaming (see "Passing 14. `rproxy` passes the request to `SWRP_UPSTREAM_URL`, streaming (see "Passing
@@ -184,19 +178,18 @@ request log's `heuristic` field gives that name. `refusal_limit` and
sent is removed. sent is removed.
15. After the visitor's answer has ended, `rproxy` sends the report (see "The 15. After the visitor's answer has ended, `rproxy` sends the report (see "The
report"). `discriminator` then counts: report"). `discriminator` then counts:
- For a request it allowed, the body bytes of the response, of the request - For a request it allowed, the response bytes, the request bytes or both
or of both are added to the byte counters, as `SWW_BYTES_COUNT` says. For are added to the byte counters, as `SWW_BYTES_COUNT` says. For a
a WebSocket, what it carried each way counts once it closes. A client WebSocket, what it carried each way counts once it closes. A client whose
whose total passes a byte limit times the percentage has broken that limit total passes a byte limit times the percentage has broken that limit and
and is banned (`byte_limits`). The request that broke it has already been is banned. The response in progress is not cut off.
passed on whole; nothing is cut off.
- For a request it allowed, the client's history and the anomaly counters - For a request it allowed, the client's history and the anomaly counters
are updated, and the alert thresholds are evaluated. are updated, and the alert thresholds are evaluated.
For a request it refused, `discriminator` adds nothing to the byte limits. For a request it refused, `discriminator` adds nothing to the byte limits.
It updates the history and the anomaly counters at its decision. It counts It updates the history and the anomaly counters at its decision. It counts
the refusals the error burst counts at the decision too (`refusal_limit`; the refusals the error burst counts at the decision too (see "Attack
see "Attack detection"). detection").
In `SWW_MODE=observe`, every refusal above is logged as what would have In `SWW_MODE=observe`, every refusal above is logged as what would have
happened, nothing is refused, and `discriminator` makes no ban of its own. A happened, nothing is refused, and `discriminator` makes no ban of its own. A
@@ -252,8 +245,7 @@ to a ban, each by its own rule:
clear sign of attack bans it permanently at once. clear sign of attack bans it permanently at once.
- A broken limit, one of: - A broken limit, one of:
- a request over a rate limit; - a request over a rate limit;
- the bytes counted for a request and its response taking the client's total - a response that takes the client's byte total past a byte limit;
past a byte limit;
- more than `SWW_ERROR_BURST_THRESHOLD` refusals within a minute. - more than `SWW_ERROR_BURST_THRESHOLD` refusals within a minute.
The bans for a broken limit: The bans for a broken limit:
@@ -441,15 +433,10 @@ the same way.
### Byte limits, per client ### Byte limits, per client
The byte limits count body bytes: the app's response bodies, the visitors' By default there is no minute limit, so a client can download in a burst at full
request bodies, or both, as `SWW_BYTES_COUNT` says. Headers are never counted. speed. The hour limit defaults to 50 GiB and the day limit to 100 GiB. They
What the visitor sent over a WebSocket counts as request bytes, and what the app allow several downloads of a few GiB each. A response's bytes are counted when
sent as response bytes. The bytes counted for a request and its response are it ends (see step 15).
added to the client's total once the response has ended (see step 15). So the
request that takes a client past a limit is passed on whole, and the ban refuses
the client's requests from then on. By default there is no minute limit, so a
client can download in a burst at full speed. The hour limit defaults to 50 GiB
and the day limit to 100 GiB. They allow several downloads of a few GiB each.
### Lookup of AS number and country ### Lookup of AS number and country
@@ -912,8 +899,7 @@ which the metrics show. They reveal a widely distributed scraper, thousands of
addresses at low rates each, which the per-client limits do not see. A low addresses at low rates each, which the per-client limits do not see. A low
`SWW_ASN_LIMIT_PERCENT` for its AS number is the response. `SWW_ASN_LIMIT_PERCENT` for its AS number is the response.
- Requests and body bytes, as `SWW_BYTES_COUNT` counts them, are counted per - Requests and bytes are counted per minute and per hour, for each of:
minute and per hour, for each of:
- a client; - a client;
- the surrounding netblock; - the surrounding netblock;
- an AS number; - an AS number;
@@ -1223,9 +1209,9 @@ short.
### Answering in time ### Answering in time
`rproxy` stops waiting for `discriminator` after `SWRP_TIMEOUT_MS`, by default 2 `rproxy` stops waiting for `discriminator` after `SWRP_TIMEOUT_MS`, by default 2
seconds, and `SWRP_DEFAULT_DISPOSITION` then decides. So the longest a question seconds, and `SWRP_DEFAULT_DISPOSITION` then decides. So at the defaults,
waits on an outside source, `SWW_LOOKUP_TIMEOUT`, is by default well within that `discriminator` answers a request well within that time, whatever the request
time, whatever the source does. and whatever its outside sources do.
GeoJS is the only outside source a question can wait on. A question waits only GeoJS is the only outside source a question can wait on. A question waits only
when step 5 says so, and for at most `SWW_LOOKUP_TIMEOUT`, by default 800 when step 5 says so, and for at most `SWW_LOOKUP_TIMEOUT`, by default 800
@@ -1321,9 +1307,9 @@ answer.
For a request it holds, `discriminator` writes the request's last log line (see For a request it holds, `discriminator` writes the request's last log line (see
"The log"). For a request it allowed, it first: "The log"). For a request it allowed, it first:
- counts the body bytes `SWW_BYTES_COUNT` names, toward the client's byte limits - counts the bytes as `SWW_BYTES_COUNT` says, toward the client's byte limits at
at the percentages it gave that request; the percentages it gave that request;
- bans a client whose total passes a byte limit; - bans a client that passes a byte limit;
- adds the request with its status to the client's history, the anomaly counters - adds the request with its status to the client's history, the anomaly counters
and the metrics. and the metrics.
docs/metrics.md
-3
View File
@@ -5,9 +5,6 @@ What `GET /_sww/metrics` answers with, at `discriminator`'s own address.
keeps the `instance` label as `exported_instance` unless the scrape sets keeps the `instance` label as `exported_instance` unless the scrape sets
`honor_labels: true`. `rproxy` has no metrics. `honor_labels: true`. `rproxy` has no metrics.
Every `sww_*request_bytes_total` and `sww_*response_bytes_total` series counts
body bytes, never headers, whatever `SWW_BYTES_COUNT` says.
## Traffic ## Traffic
- `sww_requests_total`, `sww_request_bytes_total` and - `sww_requests_total`, `sww_request_bytes_total` and
docs/request-log.md
+6 -37
View File
@@ -108,35 +108,6 @@ Every one of these lines has:
- `would_action`: in `observe` mode, what `enforce` mode would have done with a - `would_action`: in `observe` mode, what `enforce` mode would have done with a
request it would have refused. `action` then names what was done, normally request it would have refused. `action` then names what was done, normally
`forward`. `forward`.
- `heuristic`: the heuristic that refused the request, in `observe` mode too. It
is left out when none did.
- `heuristic_figures`: an object of the figures that heuristic acted on. Each
heuristic and its figures:
- `deny_nets`: `netblock`, the entry of `SWW_DENY_NETS` the client is in;
- `active_ban`: `netblock`, the ban's netblock, and `ban_expires`;
- `countries`: `country`, and `setting`, the country list that refused it;
- `blocklists`: `lists`, the blocklist URLs that list the client;
- `crowdsec`: `scenario`, the decision's scenario, and `expires`, when the
decision ends;
- `dnsbl`: `zones`, the DNS blocklist zones that list the client, their keys
masked;
- `abuseipdb`: `score`, and `min_score`, `SWW_ABUSEIPDB_MIN_SCORE`;
- `rate_limits`: `window`, `count` and `limit`;
- `trap_paths`: `path`, the trap path asked for;
- `rule_files`: `rule_id` and `rule_action`, of the rule that refused it;
- `header_limits`: `fields`, `fields_limit`, `cookies` and `cookies_limit`;
- `core_rule_set`: `score`, and `threshold`, `SWW_WAF_ANOMALY_THRESHOLD`;
- `refusal_limit`: `window`, `count` and `limit`, of the error burst;
- `byte_limits`: `window`, `count` and `limit`, the count in bytes.
- `after_answer_heuristic`: the heuristic that banned the client after
`discriminator` answered the request, in `observe` mode too: `refusal_limit`
or `byte_limits`.
- `after_answer_heuristic_figures`: an object of the figures that heuristic
acted on, as listed above.
`byte_limits` bans when the report comes, so only the `report` line names
it.
- `limit_percent` and `limit_percent_setting`: the client's percentage of the - `limit_percent` and `limit_percent_setting`: the client's percentage of the
rate limits and the setting that lowered it, when one did. `bytes_percent` and rate limits and the setting that lowered it, when one did. `bytes_percent` and
`bytes_percent_setting` do the same for the byte limits. `bytes_percent_setting` do the same for the byte limits.
@@ -144,22 +115,20 @@ Every one of these lines has:
included. It is left out when rate limiting did not count the request. It included. It is left out when rate limiting did not count the request. It
holds: holds:
- `minute`, `hour` and `day`: requests; - `minute`, `hour` and `day`: requests;
- `minute_bytes`, `hour_bytes` and `day_bytes`: the body bytes - `minute_bytes`, `hour_bytes` and `day_bytes`: bytes.
`SWW_BYTES_COUNT` names, in that window.
A count can have a fraction (see "Counting method" in A count can have a fraction (see "Counting method" in
[`SPEC.md`](../SPEC.md)). The bytes counted for an allowed request and its [`SPEC.md`](../SPEC.md)). The bytes of an allowed request are counted when
response are added when its report comes. So on the `decision` line, the its report comes. So on the `decision` line, the bytes are without this
three byte totals leave them out. request's.
- `limit_hit`: the limit broken: - `limit_hit`: the limit broken:
- `minute`, `hour` or `day` for a rate limit; - `minute`, `hour` or `day` for a rate limit;
- `minute_bytes`, `hour_bytes` or `day_bytes` for a byte limit; - `minute_bytes`, `hour_bytes` or `day_bytes` for a byte limit;
- `error_burst`. - `error_burst`.
When the bytes counted for a request and its response break a limit, the A request whose bytes broke a limit was passed on whole, so its `action`
request has been passed on whole, so its `action` stays `forward`. Only its stays `forward`. Only its `report` line gives that limit.
`report` line gives that limit.
- `rule_ids`: the rule file rules that matched, in order, up to the one that - `rule_ids`: the rule file rules that matched, in order, up to the one that
refused. refused.
docs/settings.md
+8 -22
View File
@@ -98,8 +98,6 @@ between the two (see "The image's command" below).
## Request rate limits, per client ## Request rate limits, per client
The request past one of these limits is refused, and the client is banned.
- `SWW_RATE_LIMIT_PER_MINUTE` (default `120`, 2 a second): the most requests a - `SWW_RATE_LIMIT_PER_MINUTE` (default `120`, 2 a second): the most requests a
client may make in a minute. A count or `off`. The default leaves room for a client may make in a minute. A count or `off`. The default leaves room for a
person opening two pages at once with an empty cache, up to 60 files each. person opening two pages at once with an empty cache, up to 60 files each.
@@ -122,21 +120,11 @@ The request past one of these limits is refused, and the client is banned.
## Byte limits, per client ## Byte limits, per client
These count body bytes, never headers. What the visitor sent over a WebSocket
counts as request bytes, and what the app sent as response bytes. The bytes
counted for a request and its response are added to the client's total once the
response has ended. The request that takes a client's total past a limit is not
cut off; the client is banned.
- `SWW_BYTES_LIMIT_PER_MINUTE` (default `off`), `SWW_BYTES_LIMIT_PER_HOUR` - `SWW_BYTES_LIMIT_PER_MINUTE` (default `off`), `SWW_BYTES_LIMIT_PER_HOUR`
(default `50G`) and `SWW_BYTES_LIMIT_PER_DAY` (default `100G`): the most bytes (default `50G`) and `SWW_BYTES_LIMIT_PER_DAY` (default `100G`): the most bytes
counted for a client in each window, a size or `off`: response bodies, request counted for a client in each window. A size or `off`.
bodies or both, as `SWW_BYTES_COUNT` says. The request that passes the limit - `SWW_BYTES_COUNT` (default `both`): which body bytes the byte limits count:
is not cut off, and the client is banned when its response ends. `response`, `request` or `both`.
- `SWW_BYTES_COUNT` (default `both`): what the byte limits and the byte anomaly
thresholds count: `response`, the app's response bodies; `request`, the
visitors' request bodies; or `both`. What the visitor sent over a WebSocket
counts as request bytes, and what the app sent as response bytes.
## Lookup of AS number and country ## Lookup of AS number and country
@@ -210,9 +198,8 @@ cut off; the client is banned.
a range. So does a directive that removes or changes rules as the file loads, a range. So does a directive that removes or changes rules as the file loads,
such as `SecRuleRemoveById`, since none of the Core Rule Set's rules is loaded such as `SecRuleRemoveById`, since none of the Core Rule Set's rules is loaded
yet. It has no `_FILE` form. yet. It has no `_FILE` form.
- `SWW_ERROR_BURST_THRESHOLD` (default `30`): the most refusals a client may get - `SWW_ERROR_BURST_THRESHOLD` (default `30`): the most refusals of one client in
in a minute from a rule file, a trap path or the Core Rule Set, a count or a minute (see "Attack detection" in `SPEC.md`). A count or `off`.
`off`. The next one bans the client (see "Attack detection" in `SPEC.md`).
## Ban lengths, response and scope ## Ban lengths, response and scope
@@ -289,10 +276,9 @@ cut off; the client is banned.
## Anomaly thresholds ## Anomaly thresholds
Each scope has four thresholds: the most requests and the most body bytes Each scope has four thresholds: the most requests and the most bytes counted in
counted in a minute and in an hour. The bytes are those `SWW_BYTES_COUNT` names. a minute and in an hour. Requests are counts, bytes are sizes. Each is `off` by
Requests are counts, bytes are sizes. Each is `off` by default. The four default. The four thresholds per client are:
thresholds per client are:
- `SWW_ANOMALY_CLIENT_REQUESTS_PER_MINUTE`; - `SWW_ANOMALY_CLIENT_REQUESTS_PER_MINUTE`;
- `SWW_ANOMALY_CLIENT_REQUESTS_PER_HOUR`; - `SWW_ANOMALY_CLIENT_REQUESTS_PER_HOUR`;
docs/state-files.md
+1 -1
View File
@@ -61,7 +61,7 @@ since it was first seen:
- the first and last time seen; - the first and last time seen;
- the AS number, AS name and country last looked up, and when; - the AS number, AS name and country last looked up, and when;
- total requests, and how many were forwarded and how many refused; - total requests, and how many were forwarded and how many refused;
- body bytes of its requests, and of the responses it was sent; - bytes in each direction;
- responses by status class; - responses by status class;
- offences by kind: `limit`, `attack`, `rule_blocked` and `waf_blocked`. A file - offences by kind: `limit`, `attack`, `rule_blocked` and `waf_blocked`. A file
may also hold `token_refused`, which is kept, and which nothing adds to. may also hold `token_refused`, which is kept, and which nothing adds to.
internal/config/config.go
+29 -81
View File
@@ -397,21 +397,18 @@ var (
errNotPathPrefix = errors.New( errNotPathPrefix = errors.New(
"is not a path prefix starting with /, such as /assets/") "is not a path prefix starting with /, such as /assets/")
errNotTrapPath = errors.New( errNotTrapPath = errors.New(
"is not a path starting with / and without a ?, such as /wp-login.php", "is not a path starting with / and without a ?, such as /wp-login.php")
)
errNotWAFMode = errors.New("is not off, detect or block") errNotWAFMode = errors.New("is not off, detect or block")
errNotParanoiaLevel = errors.New("is not a paranoia level, from 1 to 4") errNotParanoiaLevel = errors.New("is not a paranoia level, from 1 to 4")
errNotRuleID = errors.New( errNotRuleID = errors.New(
"is not the id of a Core Rule Set rule, a whole number such as 942100", "is not the id of a Core Rule Set rule, a whole number such as 942100")
)
errSetupRuleID = errors.New( errSetupRuleID = errors.New(
"is from 900000 to 900999, the ids of the rules that set the Core Rule Set " + "is from 900000 to 900999, the ids of the rules that set the Core Rule Set " +
"up and of sww's own, which cannot be switched off") "up and of sww's own, which cannot be switched off")
errNotBoolean = errors.New("is not true or false") errNotBoolean = errors.New("is not true or false")
errNotLogRemoteURL = errors.New( errNotLogRemoteURL = errors.New(
"is not syslog+udp, syslog+tcp or syslog+tls with a host and a port, " + "is not syslog+udp, syslog+tcp or syslog+tls with a host and a port, " +
"and nothing more, such as syslog+tls://logs.example:6514", "and nothing more, such as syslog+tls://logs.example:6514")
)
errNoCertificate = errors.New("holds no PEM certificate") errNoCertificate = errors.New("holds no PEM certificate")
errNotFacility = errors.New("is not a syslog facility such as local0 or daemon") errNotFacility = errors.New("is not a syslog facility such as local0 or daemon")
errNotAppName = errors.New( errNotAppName = errors.New(
@@ -424,21 +421,16 @@ var (
"is not a header name followed by : and the header's value, " + "is not a header name followed by : and the header's value, " +
"such as Authorization:Bearer <token>") "such as Authorization:Bearer <token>")
errControlCharacter = errors.New( errControlCharacter = errors.New(
"holds a control character, such as the carriage return of a Windows line end", "holds a control character, such as the carriage return of a Windows line end")
)
errNotAlertEvent = errors.New( errNotAlertEvent = errors.New(
"is not ban, permanent_ban, waf_block, anomaly, reputation_hit, " + "is not ban, permanent_ban, waf_block, anomaly, reputation_hit, " +
"source_failure or file_error") "source_failure or file_error")
errNotNumberOrOff = errors.New( errNotNumberOrOff = errors.New("is not a whole number above zero, such as 60, or off")
"is not a whole number above zero, such as 60, or off",
)
errNotUTF8 = errors.New("is not valid UTF-8") errNotUTF8 = errors.New("is not valid UTF-8")
errNotASN = errors.New("is not an AS number such as AS64496") errNotASN = errors.New("is not an AS number such as AS64496")
errNotPercentItem = errors.New( errNotPercentItem = errors.New(
"is not a code, : and a percentage, such as AS64496:50 or cn:25") "is not a code, : and a percentage, such as AS64496:50 or cn:25")
errNotPercent = errors.New( errNotPercent = errors.New("is not a percentage, a whole number from 0 to 100")
"is not a percentage, a whole number from 0 to 100",
)
errListedTwice = errors.New("is listed twice") errListedTwice = errors.New("is listed twice")
errNotListURL = errors.New( errNotListURL = errors.New(
"is not an http or https URL without a user or a fragment, " + "is not an http or https URL without a user or a fragment, " +
@@ -447,17 +439,11 @@ var (
errNotAnHourOrMore = errors.New("is not a duration of 1h or more, such as 24h") errNotAnHourOrMore = errors.New("is not a duration of 1h or more, such as 24h")
errNotAction = errors.New( errNotAction = errors.New(
"is not deny, limit:<percent> such as limit:25, or log") "is not deny, limit:<percent> such as limit:25, or log")
errNotZone = errors.New( errNotZone = errors.New("is not a DNS zone such as dnsbl.dronebl.org")
"is not a DNS zone such as dnsbl.dronebl.org", errZoneTooLong = errors.New("is longer than 189 characters, too long for the " +
) "names IPv6 clients are asked about by")
errZoneTooLong = errors.New( errNotResolver = errors.New("is not an IP address with an optional port, " +
"is longer than 189 characters, too long for the " + "such as 192.0.2.53 or [2001:db8::53]:5353")
"names IPv6 clients are asked about by",
)
errNotResolver = errors.New(
"is not an IP address with an optional port, " +
"such as 192.0.2.53 or [2001:db8::53]:5353",
)
errNotLAPIURL = errors.New( errNotLAPIURL = errors.New(
"is not an http or https URL without a user or a fragment, " + "is not an http or https URL without a user or a fragment, " +
"such as http://172.17.0.1:8080") "such as http://172.17.0.1:8080")
@@ -474,9 +460,7 @@ var (
// setting that is set but invalid is an error that names it. // setting that is set but invalid is an error that names it.
// //
//nolint:funlen // one line for each setting, a list that grows with them //nolint:funlen // one line for each setting, a list that grows with them
func FromEnvironment( func FromEnvironment(lookupEnv func(string) (string, bool)) (*Config, error) {
lookupEnv func(string) (string, bool),
) (*Config, error) {
env := &environment{lookupEnv: lookupEnv} env := &environment{lookupEnv: lookupEnv}
cfg := &Config{ cfg := &Config{
ListenAddr: env.address("SWW_LISTEN_ADDR"), ListenAddr: env.address("SWW_LISTEN_ADDR"),
@@ -674,10 +658,7 @@ func (e *environment) lookup(name string) (string, bool) {
} }
if set { if set {
e.check( e.check(name, fmt.Errorf("is set, and so is %s; %w", fileName, errSetTwice))
name,
fmt.Errorf("is set, and so is %s; %w", fileName, errSetTwice),
)
return value, set return value, set
} }
@@ -935,10 +916,7 @@ func (e *environment) zones(name string) []string {
logged[i] = MaskZoneKey(zone) logged[i] = MaskZoneKey(zone)
} }
e.settings = append( e.settings = append(e.settings, slog.String(name, strings.Join(logged, ",")))
e.settings,
slog.String(name, strings.Join(logged, ",")),
)
return zones return zones
} }
@@ -1080,9 +1058,7 @@ func (e *environment) headerNames(name, defaultValue string) []string {
// durationNotOff reads a setting that is a duration and, unlike a // durationNotOff reads a setting that is a duration and, unlike a
// timeout, cannot be off. // timeout, cannot be off.
func (e *environment) durationNotOff( func (e *environment) durationNotOff(name, defaultValue string) time.Duration {
name, defaultValue string,
) time.Duration {
duration, err := ParseDurationNotOff(e.value(name, defaultValue)) duration, err := ParseDurationNotOff(e.value(name, defaultValue))
e.check(name, err) e.check(name, err)
@@ -1281,10 +1257,7 @@ func (e *environment) instanceName() string {
// appName reads the setting that is the APP-NAME of the records the log // appName reads the setting that is the APP-NAME of the records the log
// lines are sent in, by default the instance name. Its value is checked // lines are sent in, by default the instance name. Its value is checked
// when it is set, and, while lines are sent, when it is the instance name. // when it is set, and, while lines are sent, when it is the instance name.
func (e *environment) appName( func (e *environment) appName(name, instanceName string, sending bool) string {
name, instanceName string,
sending bool,
) string {
value, set := e.lookup(name) value, set := e.lookup(name)
if !set { if !set {
value = instanceName value = instanceName
@@ -1307,10 +1280,7 @@ func (e *environment) appName(
// checkInstanceNameForNtfy refuses an instance name that holds a control // checkInstanceNameForNtfy refuses an instance name that holds a control
// character while ntfySet, SWW_ALERT_NTFY_URL being set: ntfy is sent // character while ntfySet, SWW_ALERT_NTFY_URL being set: ntfy is sent
// the instance name in a header, which cannot hold one. // the instance name in a header, which cannot hold one.
func (e *environment) checkInstanceNameForNtfy( func (e *environment) checkInstanceNameForNtfy(instanceName string, ntfySet bool) {
instanceName string,
ntfySet bool,
) {
if ntfySet && strings.ContainsFunc(instanceName, unicode.IsControl) { if ntfySet && strings.ContainsFunc(instanceName, unicode.IsControl) {
e.check("SWW_INSTANCE_NAME", fmt.Errorf( e.check("SWW_INSTANCE_NAME", fmt.Errorf(
"%q %w, and is sent to ntfy in a header while SWW_ALERT_NTFY_URL is set", "%q %w, and is sent to ntfy in a header while SWW_ALERT_NTFY_URL is set",
@@ -1634,10 +1604,7 @@ func parseNamedNetblocks(value string) ([]anomaly.NamedNetblock, error) {
return nil, fmt.Errorf("%q %w", name, errListedTwice) return nil, fmt.Errorf("%q %w", name, errListedTwice)
} }
named = append( named = append(named, anomaly.NamedNetblock{Name: name, Netblock: netblock})
named,
anomaly.NamedNetblock{Name: name, Netblock: netblock},
)
} }
return named, nil return named, nil
@@ -1876,11 +1843,8 @@ func parseHeaderNames(value string) ([]string, error) {
header := strings.ToLower(item) header := strings.ToLower(item)
switch header { switch header {
case "host": case "host":
return nil, fmt.Errorf( return nil, fmt.Errorf("%q %w; the request's host is the field host",
"%q %w; the request's host is the field host", item, errHeaderTakenOut)
item,
errHeaderTakenOut,
)
case "transfer-encoding": case "transfer-encoding":
return nil, fmt.Errorf("%q %w", item, errHeaderTakenOut) return nil, fmt.Errorf("%q %w", item, errHeaderTakenOut)
} }
@@ -1917,11 +1881,9 @@ func parseUpstreamURL(value string) (*url.URL, error) {
} }
onlySchemeAndHost := (upstream.Scheme == "http" || upstream.Scheme == "https") && onlySchemeAndHost := (upstream.Scheme == "http" || upstream.Scheme == "https") &&
upstream.Hostname() != "" && upstream.User == nil && upstream.Hostname() != "" && upstream.User == nil && upstream.Opaque == "" &&
upstream.Opaque == "" &&
(upstream.Path == "" || upstream.Path == "/") && (upstream.Path == "" || upstream.Path == "/") &&
upstream.RawQuery == "" && upstream.RawQuery == "" && upstream.Fragment == ""
upstream.Fragment == ""
if !onlySchemeAndHost { if !onlySchemeAndHost {
return nil, fmt.Errorf("%q %w", value, errNotUpstreamURL) return nil, fmt.Errorf("%q %w", value, errNotUpstreamURL)
} }
@@ -1945,11 +1907,7 @@ func parseLogRemoteURL(value string) (*url.URL, error) {
return nil, fmt.Errorf("%q %w", value, errNotLogRemoteURL) return nil, fmt.Errorf("%q %w", value, errNotLogRemoteURL)
} }
schemes := []string{ schemes := []string{remotelog.SchemeUDP, remotelog.SchemeTCP, remotelog.SchemeTLS}
remotelog.SchemeUDP,
remotelog.SchemeTCP,
remotelog.SchemeTLS,
}
port, err := strconv.ParseUint(remote.Port(), 10, 16) port, err := strconv.ParseUint(remote.Port(), 10, 16)
onlySchemeHostAndPort := slices.Contains(schemes, remote.Scheme) && onlySchemeHostAndPort := slices.Contains(schemes, remote.Scheme) &&
@@ -2012,9 +1970,7 @@ func isHTTPURL(u *url.URL) bool {
return (u.Scheme == "http" || u.Scheme == "https") && u.Hostname() != "" && return (u.Scheme == "http" || u.Scheme == "https") && u.Hostname() != "" &&
(u.Port() == "" || (err == nil && port != 0)) && (u.Port() == "" || (err == nil && port != 0)) &&
u.User == nil && u.User == nil && u.Opaque == "" && u.Fragment == ""
u.Opaque == "" &&
u.Fragment == ""
} }
// isListURL reports whether value is a URL a list can be fetched from, as // isListURL reports whether value is a URL a list can be fetched from, as
@@ -2081,12 +2037,9 @@ func parseZones(value string) ([]string, error) {
for i, zone := range zones { for i, zone := range zones {
shown := MaskZoneKey(zone) shown := MaskZoneKey(zone)
listedBefore := slices.ContainsFunc( listedBefore := slices.ContainsFunc(zones[:i], func(earlier string) bool {
zones[:i], return strings.EqualFold(MaskZoneKey(earlier), shown)
func(earlier string) bool { })
return strings.EqualFold(MaskZoneKey(earlier), shown)
},
)
switch { switch {
case len(zone) > maxZoneLength: case len(zone) > maxZoneLength:
@@ -2173,13 +2126,8 @@ func parseWebhookHeaders(value string) (http.Header, string, error) {
name, headerValue, found := strings.Cut(item, ":") name, headerValue, found := strings.Cut(item, ":")
name = strings.TrimSpace(name) name = strings.TrimSpace(name)
if !found || !IsHeaderName(name) || if !found || !IsHeaderName(name) || strings.ContainsAny(headerValue, "\r\n\x00") {
strings.ContainsAny(headerValue, "\r\n\x00") { return nil, "", fmt.Errorf("item %d %w", i+1, errNotWebhookHeader)
return nil, "", fmt.Errorf(
"item %d %w",
i+1,
errNotWebhookHeader,
)
} }
headers.Add(name, strings.TrimSpace(headerValue)) headers.Add(name, strings.TrimSpace(headerValue))
internal/discriminator/abuseipdb.go
-55
View File
@@ -1,55 +0,0 @@
package discriminator
// The heuristic abuseipdb. It reads SWW_ABUSEIPDB_KEY,
// SWW_ABUSEIPDB_MIN_SCORE and SWW_REPUTATION_ACTION.
import (
"context"
"time"
"sneak.berlin/go/smallwebwaf/internal/bans"
"sneak.berlin/go/smallwebwaf/internal/ratelimit"
"sneak.berlin/go/smallwebwaf/internal/reputation"
"sneak.berlin/go/smallwebwaf/internal/requestlog"
)
// abuseIPDB notes AbuseIPDB, as noteHit does, with the score, when its score
// of the client is a hit, and refuses the request when SWW_REPUTATION_ACTION
// is deny, as dnsbl does for a zone. While SWW_ABUSEIPDB_KEY is unset it does
// nothing. A client without a score is checked in the background, by the
// request's address, if its history counts an offence, and the request does
// not wait for the answer. The score is then used for each address of the
// client. Its figures are the score and SWW_ABUSEIPDB_MIN_SCORE.
type abuseIPDB struct{}
func (abuseIPDB) name() string { return "abuseipdb" }
func (abuseIPDB) check(ctx context.Context, rq *request, _ time.Time) *verdict {
if rq.h.config.AbuseIPDBKey == "" {
return nil
}
client := rq.h.clientGroup(rq.client)
held, _ := rq.h.limiter.Client(client)
offender := held.History.Offences != ratelimit.Offences{}
score, hit := rq.h.abuseIPDB.Hit(ctx, client, rq.client, offender)
if !hit {
return nil
}
rq.abuseIPDBHit = true
rq.noteHit(bans.ReputationHit{Source: reputation.AbuseIPDBSource, Score: &score},
"scored by AbuseIPDB at or over SWW_ABUSEIPDB_MIN_SCORE")
if rq.h.config.ReputationAction != deny {
return nil
}
return &verdict{
action: requestlog.ActionDenied,
figures: map[string]any{
figureScore: score, "min_score": rq.h.config.AbuseIPDBMinScore,
},
}
}
internal/discriminator/answertime_test.go
-12
View File
@@ -91,18 +91,6 @@ func TestSixteenThousandCookiesAreRefusedWellWithinTheTimeLimit(t *testing.T) {
} }
} }
func TestHeaderLimitRefusalNamesItsHeuristicCountsAndLimits(t *testing.T) {
t.Parallel()
s := startDiscriminator(t, "", nil)
req := s.question(siteA, client, "/")
fillHeaders(req, headerFieldLimit+1)
do(t, req)
wantHeuristic(t, s.out.requestLine(t), "header_limits",
`{"fields": 101, "fields_limit": 100, "cookies": 0, "cookies_limit": 50}`)
}
func TestEachHeaderLimitRefusesARequestOverIt(t *testing.T) { func TestEachHeaderLimitRefusesARequestOverIt(t *testing.T) {
t.Parallel() t.Parallel()
internal/discriminator/bans.go
+79 -25
View File
@@ -1,10 +1,7 @@
package discriminator package discriminator
// The heuristic active_ban, and the code that makes bans, which several
// heuristics share. active_ban reads SWW_MODE; the bans are the ban ledger's.
import ( import (
"context" "net/http"
"net/netip" "net/netip"
"time" "time"
@@ -21,15 +18,11 @@ func (rq *request) banResponse(action string) *refusal {
return &refusal{status: rq.h.config.BanResponse, action: action} return &refusal{status: rq.h.config.BanResponse, action: action}
} }
// activeBan refuses a client a ban covers: a ban on a netblock the client is // banned reports whether a ban on a netblock the client is in covers the
// in, in force at now. It notes for the log line when that ban ends. A request // request at now, and notes for the log line when that ban ends. A
// that makes the ban permanent, or in observe mode would have, raises the alert // request that makes the ban permanent, or in observe mode would have,
// for it. Its figures are the ban's netblock and when it ends. // raises the alert for it.
type activeBan struct{} func (rq *request) banned(now time.Time) bool {
func (activeBan) name() string { return "active_ban" }
func (activeBan) check(_ context.Context, rq *request, now time.Time) *verdict {
check := rq.h.ledger.Check check := rq.h.ledger.Check
if rq.h.config.Observe { if rq.h.config.Observe {
check = rq.h.ledger.Find // the ban refuses nothing, and stays as it is check = rq.h.ledger.Find // the ban refuses nothing, and stays as it is
@@ -45,24 +38,85 @@ func (activeBan) check(_ context.Context, rq *request, now time.Time) *verdict {
rq.alertBan(ban) rq.alertBan(ban)
} }
if !banned { return banned
return nil }
// limitBroken counts the request for the rate limits at now, notes the
// client's counts for the log line, and reports whether the request takes
// the client over a rate limit, as its limit percentage lowers it, which
// breaks it.
func (rq *request) limitBroken(now time.Time) bool {
counts, hit, over := rq.h.limiter.Count(rq.h.clientGroup(rq.client), now,
rq.limitPercent.percent)
rq.line.Counts = counts
if over {
rq.banForLimit(now, hit, rq.h.config.BanResponse)
} }
return &verdict{ return over
action: requestlog.ActionBanned, }
figures: map[string]any{
figureNetblock: ban.Netblock.String(), "ban_expires": rq.line.BanExpires, // countBytes counts the request's bytes, as countedBytes gives them, for
}, // the byte limits, once its report has come, and notes the client's byte totals
// for the log line; its requests stay there as the rate limits counted them.
// Only an allowed request has them counted, and only one the rate limits
// counted; in observe mode, not one that enforce mode would have refused. Bytes
// that take the client over a byte limit, as its limit percentage for the byte
// limits lowers it, break it; the response was passed on whole.
func (rq *request) countBytes() {
if !rq.counted || rq.line.WouldAction != "" {
return
}
now := rq.h.now()
counts, hit, over := rq.h.limiter.CountBytes(rq.h.clientGroup(rq.client), now,
rq.countedBytes(), rq.bytesPercent.percent)
rq.line.Counts.MinuteBytes = counts.MinuteBytes
rq.line.Counts.HourBytes = counts.HourBytes
rq.line.Counts.DayBytes = counts.DayBytes
if over {
rq.banForLimit(now, hit, rq.out.status)
} }
} }
// limitFigures are the figures of a heuristic that broke hit, a limit: its // countRefusal counts the request for the error burst once it has been
// window, the count and the limit. // answered, if discriminator refused it after a rule file match, a trap path or a
func limitFigures(hit ratelimit.Hit) map[string]any { // Core Rule Set match, and in observe mode if enforce mode would have: more than
return map[string]any{ // SWW_ERROR_BURST_THRESHOLD such refusals of the client within a minute
figureWindow: hit.Window, figureCount: hit.Count, figureLimit: hit.Limit, // break a limit. A client in SWW_ALLOW_NETS, which the checks skip, is
// not counted, and nothing is while the threshold is off.
func (rq *request) countRefusal() {
cfg := rq.h.config
if cfg.ErrorBurstThreshold == 0 {
return
} }
if !rq.attack && !rq.ruleBlocked && !rq.wafBlocked {
return
}
now := rq.h.now()
hit, over := rq.h.limiter.CountRefusal(rq.h.clientGroup(rq.client), now,
cfg.ErrorBurstThreshold)
if !over {
return
}
// What the client was sent, or in observe mode would have been.
status := rq.out.status
switch rq.line.WouldAction {
case requestlog.ActionRuleBlocked, requestlog.ActionWAFBlocked:
status = http.StatusForbidden
case requestlog.ActionBanned:
status = cfg.BanResponse
}
rq.banForLimit(now, hit, status)
} }
// countedBytes returns the request's bytes, once it has ended, as the // countedBytes returns the request's bytes, once it has ended, as the
internal/discriminator/bans_test.go
-16
View File
@@ -228,22 +228,6 @@ func TestBannedClientIsRefusedBeforeItsCountryIsLookedUp(t *testing.T) {
} }
} }
func TestRefusalUnderABanNamesItsHeuristicNetblockAndEnd(t *testing.T) {
t.Parallel()
s, clk, _ := startWithClock(t, "", map[string]string{
rateLimitPerMinute: "1", banScopeV4Prefix: "24",
})
expires := requestlog.FormatTime(clk.Now().Add(time.Hour))
s.get(client, http.StatusOK, requestlog.ActionForward)
s.get(client, http.StatusForbidden, requestlog.ActionRateLimited)
line := s.get(otherClient, http.StatusForbidden, requestlog.ActionBanned)
wantHeuristic(t, line, "active_ban",
`{"netblock": "`+clientsNet+`", "ban_expires": "`+expires+`"}`)
}
func TestBanResponseAnswersEveryRefusalButTheSizeLimits(t *testing.T) { func TestBanResponseAnswersEveryRefusalButTheSizeLimits(t *testing.T) {
t.Parallel() t.Parallel()
internal/discriminator/blocklists.go
-41
View File
@@ -1,41 +0,0 @@
package discriminator
// The heuristic blocklists. It reads SWW_BLOCKLIST_ACTION, and the blocklists
// through the reputation lists.
import (
"context"
"time"
"sneak.berlin/go/smallwebwaf/internal/requestlog"
)
// blocklists notes the blocklists that list the client, as noteListed does,
// and refuses the request when SWW_BLOCKLIST_ACTION is deny. Being limit, it
// lowers the client's limits instead (see limitPercentages), and being log, it
// does nothing more. Its figure is the blocklists that list the client.
type blocklists struct{}
func (blocklists) name() string { return "blocklists" }
func (blocklists) check(_ context.Context, rq *request, _ time.Time) *verdict {
listedBy := rq.h.lists.ListedBy(rq.client)
rq.blocklisted = len(listedBy) > 0
rq.noteListed(listedBy, "listed by a blocklist")
if !rq.refusedByBlocklists(listedBy) {
return nil
}
return &verdict{
action: requestlog.ActionDenied,
figures: map[string]any{"lists": listedBy},
}
}
// refusedByBlocklists reports whether the heuristic blocklists refuses a
// client, given listedBy, the blocklists that list it: it does when one lists
// it and SWW_BLOCKLIST_ACTION is deny.
func (rq *request) refusedByBlocklists(listedBy []string) bool {
return len(listedBy) > 0 && rq.h.config.BlocklistAction == deny
}
internal/discriminator/bytelimits.go
-43
View File
@@ -1,43 +0,0 @@
package discriminator
// The heuristic byte_limits. It reads SWW_BYTES_COUNT, and the byte limits
// and biased thresholds through the limiter and limitPercentages.
import (
"context"
"time"
"sneak.berlin/go/smallwebwaf/internal/requestlog"
)
// byteLimits counts the request's bytes, as countedBytes gives them, for the
// byte limits, once its report has come, and notes the client's byte totals for
// the log line; its requests stay there as the rate limits counted them. Only
// an allowed request has them counted, and only one the rate limits counted; in
// observe mode, not one that enforce mode would have refused. Bytes that take
// the client over a byte limit, as its limit percentage for the byte limits
// lowers it, break it, which bans the client; the response was passed on whole.
// Its figures are the window, the count and the limit.
type byteLimits struct{}
func (byteLimits) name() string { return "byte_limits" }
func (byteLimits) check(_ context.Context, rq *request, now time.Time) *verdict {
if !rq.counted || rq.line.WouldAction != "" {
return nil
}
counts, hit, over := rq.h.limiter.CountBytes(rq.h.clientGroup(rq.client), now,
rq.countedBytes(), rq.bytesPercent.percent)
rq.line.Counts.MinuteBytes = counts.MinuteBytes
rq.line.Counts.HourBytes = counts.HourBytes
rq.line.Counts.DayBytes = counts.DayBytes
if !over {
return nil
}
rq.banForLimit(now, hit, rq.out.status)
return &verdict{action: requestlog.ActionBanned, figures: limitFigures(hit)}
}
internal/discriminator/bytelimits_test.go
-15
View File
@@ -98,21 +98,6 @@ func TestEachByteLimitBansOnceTheResponseHasEnded(t *testing.T) {
} }
} }
func TestByteLimitBanNamesItsHeuristicWindowCountAndLimit(t *testing.T) {
t.Parallel()
s, _ := startWithAnswers(t, map[string]string{bytesLimitPerMinute: byteLimit})
line, _ := s.download()
wantAfterAnswerHeuristic(t, line, "", "null")
// Two answers of 70 bytes are over the limit of 99.
line, _ = s.download()
wantHeuristic(t, line, "", "null")
wantAfterAnswerHeuristic(t, line, "byte_limits",
`{"window": "minute", "count": 140, "limit": 99}`)
}
func TestResponseOverAByteLimitByItselfIsPassedOnWhole(t *testing.T) { func TestResponseOverAByteLimitByItselfIsPassedOnWhole(t *testing.T) {
t.Parallel() t.Parallel()
internal/discriminator/coreruleset.go
+9 -19
View File
@@ -1,10 +1,6 @@
package discriminator package discriminator
// The heuristic core_rule_set. It reads SWW_WAF_MODE, SWW_WAF_EXEMPT_PATHS
// and SWW_WAF_ANOMALY_THRESHOLD.
import ( import (
"context"
"time" "time"
"sneak.berlin/go/smallwebwaf/internal/alerts" "sneak.berlin/go/smallwebwaf/internal/alerts"
@@ -13,21 +9,18 @@ import (
"sneak.berlin/go/smallwebwaf/internal/waf" "sneak.berlin/go/smallwebwaf/internal/waf"
) )
// coreRuleSet inspects the request with the Core Rule Set, unless // checkCoreRuleSet inspects the request with the Core Rule Set, unless
// SWW_WAF_MODE is off or SWW_WAF_EXEMPT_PATHS exempts its path, as // SWW_WAF_MODE is off or SWW_WAF_EXEMPT_PATHS exempts its path, as
// pathExempt decides, and notes the rules it matched and its score in the // pathExempt decides, and notes the rules it matched and its score in the
// log line, and the rules in the metrics. A score at or over // log line, and the rules in the metrics. A score at or over
// SWW_WAF_ANOMALY_THRESHOLD is a match: it raises the waf_block alert, // SWW_WAF_ANOMALY_THRESHOLD is a match: it raises the waf_block alert,
// and in block mode refuses the request with 403, which is an offence its // and in block mode refuses the request, which is an offence its client's
// client's history counts. Its figures are the score and the threshold. // history counts, and so returns ActionWAFBlocked. It returns "" for a
type coreRuleSet struct{} // request it does not refuse.
func (rq *request) checkCoreRuleSet() string {
func (coreRuleSet) name() string { return "core_rule_set" }
func (coreRuleSet) check(_ context.Context, rq *request, _ time.Time) *verdict {
cfg := rq.h.config cfg := rq.h.config
if cfg.WAFMode == config.WAFModeOff || pathExempt(rq.in, cfg.WAFExemptPaths) { if cfg.WAFMode == config.WAFModeOff || pathExempt(rq.in, cfg.WAFExemptPaths) {
return nil return ""
} }
start := time.Now() start := time.Now()
@@ -47,21 +40,18 @@ func (coreRuleSet) check(_ context.Context, rq *request, _ time.Time) *verdict {
threshold := cfg.WAFAnomalyThreshold threshold := cfg.WAFAnomalyThreshold
if threshold == 0 || result.Score < threshold { if threshold == 0 || result.Score < threshold {
return nil return ""
} }
rq.alertWAFBlock(result) rq.alertWAFBlock(result)
if cfg.WAFMode == config.WAFModeDetect { if cfg.WAFMode == config.WAFModeDetect {
return nil return ""
} }
rq.wafBlocked = true rq.wafBlocked = true
return &verdict{ return requestlog.ActionWAFBlocked
action: requestlog.ActionWAFBlocked,
figures: map[string]any{figureScore: result.Score, "threshold": threshold},
}
} }
// alertWAFBlock raises the waf_block alert for the request, which the Core // alertWAFBlock raises the waf_block alert for the request, which the Core
internal/discriminator/coreruleset_test.go
-10
View File
@@ -110,16 +110,6 @@ func TestCoreRuleSetRefusesAttacksInBlockModeAndOnlyLogsThemInDetectMode(t *test
} }
} }
func TestCoreRuleSetRefusalNamesItsHeuristicScoreAndThreshold(t *testing.T) {
t.Parallel()
s, _, _ := startWithClock(t, "", map[string]string{wafMode: block})
line := s.request(client, sqlInjection, http.StatusForbidden,
requestlog.ActionWAFBlocked)
wantHeuristic(t, line, "core_rule_set", `{"score": 5, "threshold": 5}`)
}
func TestOrdinaryRequestIsInspectedAndPassed(t *testing.T) { func TestOrdinaryRequestIsInspectedAndPassed(t *testing.T) {
t.Parallel() t.Parallel()
internal/discriminator/countries.go
+8 -29
View File
@@ -1,42 +1,21 @@
package discriminator package discriminator
// The heuristic countries. It reads SWW_DENIED_COUNTRIES and
// SWW_EXCLUSIVELY_ALLOWED_COUNTRIES.
import ( import (
"context"
"slices" "slices"
"time"
"sneak.berlin/go/smallwebwaf/internal/requestlog"
) )
// countries refuses a request by the client's country as it was looked up. A // countryDenied reports whether the country lists refuse the request, by
// client without a country, or whose country cannot be found, is refused only // the client's country as it was looked up. A client without a country,
// by SWW_EXCLUSIVELY_ALLOWED_COUNTRIES. Its figures are the country and the // or whose country cannot be found, is refused only by
// setting that refused it. // SWW_EXCLUSIVELY_ALLOWED_COUNTRIES.
type countries struct{} func (rq *request) countryDenied() bool {
func (countries) name() string { return "countries" }
func (countries) check(_ context.Context, rq *request, _ time.Time) *verdict {
denied := rq.h.config.DeniedCountries denied := rq.h.config.DeniedCountries
allowed := rq.h.config.ExclusivelyAllowedCountries allowed := rq.h.config.ExclusivelyAllowedCountries
country := rq.line.Country country := rq.line.Country
var setting string if slices.Contains(denied, country) {
return true
switch {
case slices.Contains(denied, country):
setting = "SWW_DENIED_COUNTRIES"
case len(allowed) > 0 && !slices.Contains(allowed, country):
setting = "SWW_EXCLUSIVELY_ALLOWED_COUNTRIES"
default:
return nil
} }
return &verdict{ return len(allowed) > 0 && !slices.Contains(allowed, country)
action: requestlog.ActionCountryDenied,
figures: map[string]any{"country": country, "setting": setting},
}
} }
internal/discriminator/countries_test.go
-17
View File
@@ -90,23 +90,6 @@ func TestCountryLists(t *testing.T) {
} }
} }
func TestCountryRefusalNamesItsHeuristicCountryAndSetting(t *testing.T) {
t.Parallel()
geojsURL, _ := startGeoJS(t)
s, _, _ := startWithClock(t, geojsURL, map[string]string{
lookupTimeout: "1h", deniedCountries: "kp", allowedCountries: "de",
})
line := s.get(fromKP, http.StatusForbidden, requestlog.ActionCountryDenied)
wantHeuristic(t, line, "countries",
`{"country": "KP", "setting": "SWW_DENIED_COUNTRIES"}`)
line = s.get(unplaced, http.StatusForbidden, requestlog.ActionCountryDenied)
wantHeuristic(t, line, "countries",
`{"country": "", "setting": "SWW_EXCLUSIVELY_ALLOWED_COUNTRIES"}`)
}
func TestCountryRefusalKeepsARequestFromTheApp(t *testing.T) { func TestCountryRefusalKeepsARequestFromTheApp(t *testing.T) {
t.Parallel() t.Parallel()
internal/discriminator/crowdsec.go
-49
View File
@@ -1,49 +0,0 @@
package discriminator
// The heuristic crowdsec. It reads SWW_CROWDSEC_LAPI_URL, and the decisions
// through the reputation lists.
import (
"context"
"time"
"sneak.berlin/go/smallwebwaf/internal/bans"
"sneak.berlin/go/smallwebwaf/internal/reputation"
"sneak.berlin/go/smallwebwaf/internal/requestlog"
)
// crowdSec refuses a request when a decision of the CrowdSec decision list on
// the client is in force at now. It then notes the list, as noteHit does, and
// bans the client until that decision ends. Its figures are the decision's
// scenario and when it ends.
type crowdSec struct{}
func (crowdSec) name() string { return "crowdsec" }
func (crowdSec) check(_ context.Context, rq *request, now time.Time) *verdict {
decision, listed := rq.crowdSecDecisionInForce(now)
if !listed {
return nil
}
rq.noteHit(bans.ReputationHit{Source: rq.h.config.CrowdSecDecisionsURL},
"listed by the CrowdSec decision list")
rq.banForCrowdSec(now, decision)
return &verdict{
action: requestlog.ActionBanned,
figures: map[string]any{
"scenario": decision.Scenario,
"expires": requestlog.FormatTime(decision.Expires),
},
}
}
// crowdSecDecisionInForce returns the decision of the CrowdSec decision list on
// the client that is in force at now, and reports whether there is one, which
// the heuristic crowdsec refuses the request for.
func (rq *request) crowdSecDecisionInForce(
now time.Time,
) (reputation.Decision, bool) {
return rq.h.lists.CrowdSecDecision(rq.client, now)
}
internal/discriminator/crowdsec_test.go
-15
View File
@@ -95,21 +95,6 @@ func TestClientTheCrowdSecDecisionListListsIsBannedUntilTheDecisionEnds(t *testi
float64(fetched.Unix())) float64(fetched.Unix()))
} }
func TestCrowdSecBanNamesItsHeuristicScenarioAndEnd(t *testing.T) {
t.Parallel()
s, clk, server, _ := startWithAlerts(t, map[string]string{
crowdSecURL: lapi, crowdSecKey: bouncerKey,
})
loadDecisions(t, server, clk.Now(), `[{"duration": "4h0m0s", `+
`"scenario": "crowdsecurity/ssh-bf", "scope": "Ip", "type": "ban", `+
`"value": "`+client+`"}]`)
line := s.get(client, http.StatusForbidden, requestlog.ActionBanned)
wantHeuristic(t, line, "crowdsec", `{"scenario": "crowdsecurity/ssh-bf", `+
`"expires": "`+requestlog.FormatTime(clk.Now().Add(4*time.Hour))+`"}`)
}
func TestEndedCrowdSecDecisionNoLongerBansThoughTheCopyStillHoldsIt(t *testing.T) { func TestEndedCrowdSecDecisionNoLongerBansThoughTheCopyStillHoldsIt(t *testing.T) {
t.Parallel() t.Parallel()
internal/discriminator/denynets.go
-29
View File
@@ -1,29 +0,0 @@
package discriminator
// The heuristic deny_nets. It reads SWW_DENY_NETS.
import (
"context"
"time"
"sneak.berlin/go/smallwebwaf/internal/requestlog"
)
// denyNets refuses a client in SWW_DENY_NETS. Its figure is the netblock of
// the setting the client is in.
type denyNets struct{}
func (denyNets) name() string { return "deny_nets" }
func (denyNets) check(_ context.Context, rq *request, _ time.Time) *verdict {
for _, netblock := range rq.h.config.DenyNets {
if netblock.Contains(rq.client) {
return &verdict{
action: requestlog.ActionDenied,
figures: map[string]any{figureNetblock: netblock.String()},
}
}
}
return nil
}
internal/discriminator/discriminator.go
+54 -20
View File
@@ -2,7 +2,6 @@ package discriminator
import ( import (
"bytes" "bytes"
"context"
"encoding/json" "encoding/json"
"errors" "errors"
"fmt" "fmt"
@@ -53,6 +52,13 @@ const ReportPath = "/_sww/report"
// QuestionBodyMaxBytes is the most of a visitor's body a question carries. // QuestionBodyMaxBytes is the most of a visitor's body a question carries.
const QuestionBodyMaxBytes = 64 << 10 const QuestionBodyMaxBytes = 64 << 10
// The header limits: the most cookies and header fields a request may have
// when the checks reach the Core Rule Set. Real clients never reach them.
const (
maxCookies = 50
maxHeaderFields = 100
)
const ( const (
// maxAwaitingReport is the most answered requests held until their // maxAwaitingReport is the most answered requests held until their
// reports come. Past it, the request answered longest ago is dropped. // reports come. Past it, the request answered longest ago is dropped.
@@ -142,20 +148,48 @@ func (h *handler) ServeHTTP(w http.ResponseWriter, r *http.Request) {
// refusedWhateverTheAnswer reports whether the request is one that does not wait // 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 // for GeoJS, since the checks will refuse it at now whatever GeoJS answers about
// its client: the heuristic crowdsec, header_limits, blocklists or rate_limits // its client: it is over the header limits, a blocklist lists its client while
// will refuse it, as a function in that heuristic's file says. In observe mode, // SWW_BLOCKLIST_ACTION is deny, the CrowdSec decision list lists it, or it is
// which refuses nothing, none is. rproxy lets a request through when // over a whole rate limit. In observe mode, which refuses nothing, none is.
// discriminator answers too late. // rproxy lets a request through when discriminator answers too late.
func (rq *request) refusedWhateverTheAnswer(now time.Time) bool { func (rq *request) refusedWhateverTheAnswer(now time.Time) bool {
if rq.h.config.Observe { if rq.h.config.Observe {
return false return false
} }
_, decided := rq.crowdSecDecisionInForce(now) lists := rq.h.lists
_, decided := lists.CrowdSecDecision(rq.client, now)
return decided || overHeaderLimits(rq.headerCounts()) || return decided || rq.overHeaderLimits() ||
rq.refusedByBlocklists(rq.h.lists.ListedBy(rq.client)) || (rq.h.config.BlocklistAction == deny && len(lists.ListedBy(rq.client)) > 0) ||
rq.overAWholeRateLimit(now) (rq.countedByRateLimits() &&
rq.h.limiter.OverARateLimit(rq.h.clientGroup(rq.client), now))
}
// overHeaderLimits reports whether discriminator refuses the request for its
// headers: it has more than maxHeaderFields fields, each value of a header sent
// twice being one, or more than maxCookies cookies, each part of a Cookie header
// between semicolons being one unless it is empty or only spaces and tabs. The
// Core Rule Set runs each of its rules on each cookie, so that thousands of small
// cookies keep it busy for over a second. It trims only spaces and control
// characters, of which a header value can hold only tabs, so a part of Unicode
// spaces is a cookie to it.
func (rq *request) overHeaderLimits() bool {
fields, cookies := 0, 0
for _, values := range rq.in.Header {
fields += len(values)
}
for _, value := range rq.in.Header.Values("Cookie") {
for part := range strings.SplitSeq(value, ";") {
if strings.Trim(part, " \t") != "" {
cookies++
}
}
}
return fields > maxHeaderFields || cookies > maxCookies
} }
// answerQuestion runs the checks on the visitor's request a question // answerQuestion runs the checks on the visitor's request a question
@@ -186,18 +220,18 @@ func (h *handler) answerQuestion(w http.ResponseWriter, r *http.Request) {
if refused == nil && !underOwnPrefix { if refused == nil && !underOwnPrefix {
// In observe mode, what enforce mode would have refused counts here. // In observe mode, what enforce mode would have refused counts here.
defer rq.runAfterAnswer(r.Context()) defer rq.countRefusal()
rq.allow() rq.allow()
return return
} }
// The last deferred runs first: runAfterAnswer before addToHistory, so that // The last deferred runs first: countRefusal before addToHistory, so that a
// a broken refusal limit is in the client's history. // broken error burst is in the client's history.
defer rq.addToHistory() defer rq.addToHistory()
defer rq.countAnomalies() defer rq.countAnomalies()
defer rq.runAfterAnswer(r.Context()) defer rq.countRefusal()
if refused != nil { if refused != nil {
rq.deny(*refused) rq.deny(*refused)
@@ -379,7 +413,7 @@ func (h *handler) takeReport(w http.ResponseWriter, r *http.Request) {
// Remove reports true to one report only, of several that name the id. A // Remove reports true to one report only, of several that name the id. A
// question still being handled is held as nil. // question still being handled is held as nil.
if found && held != nil && h.awaitingReport.Remove(report.RequestID) { if found && held != nil && h.awaitingReport.Remove(report.RequestID) {
h.finishWith(r.Context(), held, report) h.finishWith(held, report)
} }
w.WriteHeader(http.StatusNoContent) w.WriteHeader(http.StatusNoContent)
@@ -442,11 +476,11 @@ func (report *Report) checkRanges() error {
// finishWith finishes a request with what its report says, and writes the // finishWith finishes a request with what its report says, and writes the
// request's last log line, which holds its decision's fields and the report's. // request's last log line, which holds its decision's fields and the report's.
// For an allowed request it first runs the heuristics of onReport, and adds the // For an allowed request it first counts the request's bytes, and adds it to its
// request to its client's history, the anomaly counters and the metrics, with // client's history, the anomaly counters and the metrics, with the status and
// the status and bytes the report gives. A denied request's counting was // bytes the report gives. A denied request's counting was finished at its
// finished at its decision. ctx is the report's own context. // decision.
func (h *handler) finishWith(ctx context.Context, held *decision, report Report) { func (h *handler) finishWith(held *decision, report Report) {
rq := &request{ rq := &request{
decision: *held, decision: *held,
h: h, h: h,
@@ -463,7 +497,7 @@ func (h *handler) finishWith(ctx context.Context, held *decision, report Report)
if rq.allowed { if rq.allowed {
rq.line.DurationUpstreamTotal = &report.DurationUpstreamTotal rq.line.DurationUpstreamTotal = &report.DurationUpstreamTotal
rq.runBanningHeuristics(ctx, onReport()) rq.countBytes()
rq.countAnomalies() rq.countAnomalies()
rq.addToHistory() rq.addToHistory()
internal/discriminator/dnsbl.go
-36
View File
@@ -1,36 +0,0 @@
package discriminator
// The heuristic dnsbl. It reads SWW_REPUTATION_ACTION, and the DNSBL zones'
// verdicts through the DNSBL checker.
import (
"context"
"time"
"sneak.berlin/go/smallwebwaf/internal/requestlog"
)
// dnsbl notes the DNSBL zones whose verdict lists the client, as noteListed
// does, and refuses the request when SWW_REPUTATION_ACTION is deny. Being
// limit, it lowers the client's limits instead (see limitPercentages), and
// being log, it does nothing more. A zone without a verdict on the client is
// asked about it in the background, and the request does not wait for the
// answer. Its figure is the zones that list the client, their keys masked.
type dnsbl struct{}
func (dnsbl) name() string { return "dnsbl" }
func (dnsbl) check(ctx context.Context, rq *request, _ time.Time) *verdict {
listedBy := rq.h.dnsbl.ListedBy(ctx, rq.client)
rq.dnsblListed = len(listedBy) > 0
rq.noteListed(listedBy, "listed by a DNSBL zone")
if !rq.dnsblListed || rq.h.config.ReputationAction != deny {
return nil
}
return &verdict{
action: requestlog.ActionDenied,
figures: map[string]any{"zones": listedBy},
}
}
internal/discriminator/refusallimit_test.go → internal/discriminator/errorburst_test.go
-19
View File
@@ -106,25 +106,6 @@ func TestErrorBurstBreaksAtOneOverTheThreshold(t *testing.T) {
} }
} }
func TestRefusalLimitBanNamesItsHeuristicWindowCountAndLimit(t *testing.T) {
t.Parallel()
s, _, _ := startForErrorBurst(t, "1", nil)
const ruleFigures = `{"rule_id": "blocked", "rule_action": "block"}`
line := blockRule.send(s, client)
wantHeuristic(t, line, "rule_files", ruleFigures)
wantAfterAnswerHeuristic(t, line, "", "null")
// The second refusal is the request refusal_limit bans for, and the line
// names both.
line = blockRule.send(s, client)
wantHeuristic(t, line, "rule_files", ruleFigures)
wantAfterAnswerHeuristic(t, line, "refusal_limit",
`{"window": "minute", "count": 2, "limit": 1}`)
}
func TestErrorBurstBanNotesHistoryAndMetrics(t *testing.T) { func TestErrorBurstBanNotesHistoryAndMetrics(t *testing.T) {
t.Parallel() t.Parallel()
internal/discriminator/headerlimits.go
-71
View File
@@ -1,71 +0,0 @@
package discriminator
// The heuristic header_limits. It reads no setting: its limits are fixed.
import (
"context"
"strings"
"time"
"sneak.berlin/go/smallwebwaf/internal/requestlog"
)
// The header limits: the most cookies and header fields a request may have
// when the checks reach the Core Rule Set. Real clients never reach them.
const (
maxCookies = 50
maxHeaderFields = 100
)
// headerLimits refuses a request over the header limits, with 431. Its figures
// are the request's header fields and cookies, and the limit of each.
type headerLimits struct{}
func (headerLimits) name() string { return "header_limits" }
func (headerLimits) check(_ context.Context, rq *request, _ time.Time) *verdict {
fields, cookies := rq.headerCounts()
if !overHeaderLimits(fields, cookies) {
return nil
}
return &verdict{
action: requestlog.ActionTooLarge,
figures: map[string]any{
"fields": fields, "fields_limit": maxHeaderFields,
"cookies": cookies, "cookies_limit": maxCookies,
},
}
}
// overHeaderLimits reports whether a request with these counts of header fields
// and cookies, as headerCounts counts them, is over the header limits: it has
// more than maxHeaderFields fields or more than maxCookies cookies.
func overHeaderLimits(fields, cookies int) bool {
return fields > maxHeaderFields || cookies > maxCookies
}
// headerCounts returns the request's header fields, each value of a header sent
// twice being one, and its cookies, each part of a Cookie header between
// semicolons being one unless it is empty or only spaces and tabs. The Core
// Rule Set runs each of its rules on each cookie, so that thousands of small
// cookies keep it busy for over a second. It trims only spaces and control
// characters, of which a header value can hold only tabs, so a part of Unicode
// spaces is a cookie to it.
func (rq *request) headerCounts() (int, int) {
fields, cookies := 0, 0
for _, values := range rq.in.Header {
fields += len(values)
}
for _, value := range rq.in.Header.Values("Cookie") {
for part := range strings.SplitSeq(value, ";") {
if strings.Trim(part, " \t") != "" {
cookies++
}
}
}
return fields, cookies
}
internal/discriminator/heuristics.go
-134
View File
@@ -1,134 +0,0 @@
package discriminator
import (
"context"
"time"
)
// To add a heuristic, write one file with a type that implements heuristic,
// and add one line for it to one of the lists below. Its settings go in
// config.Config, and the comment at the top of its file names them.
// heuristic is one of the checks that decide what discriminator does with a
// request.
type heuristic interface {
// name is the heuristic's name, which the log line gives.
name() string
// check looks at the request at now, and returns nil to let it through.
// ctx is the request's own context.
check(ctx context.Context, rq *request, now time.Time) *verdict
}
// verdict is a heuristic refusing a request, or banning its client: the action
// the log line names, one of requestlog's Action constants, and the figures the
// heuristic acted on, by name, such as the count and the limit.
type verdict struct {
action string
figures map[string]any
}
// The names of the figures that more than one heuristic gives.
const (
figureWindow = "window"
figureCount = "count"
figureLimit = "limit"
figureScore = "score"
figureNetblock = "netblock"
)
// The lists of heuristics, each in the order its heuristics run. A client in
// SWW_ALLOW_NETS skips them all.
// beforeLookup are the heuristics that run before the client's AS number and
// country are looked up, so that a client they refuse is not looked up.
func beforeLookup() []heuristic {
return []heuristic{
denyNets{},
activeBan{},
}
}
// afterLookup are the heuristics that run once the lookup has been made.
func afterLookup() []heuristic {
return []heuristic{
countries{},
blocklists{},
crowdSec{},
dnsbl{},
abuseIPDB{},
rateLimits{},
trapPaths{},
ruleFiles{},
headerLimits{},
coreRuleSet{},
}
}
// afterAnswer are the heuristics that run on a request once discriminator has
// answered it, before its decision line is written. They ban the client, and do
// not change what the request got: their verdict's action is not used.
func afterAnswer() []heuristic {
return []heuristic{
refusalLimit{},
}
}
// onReport are the heuristics that run on an allowed request when rproxy's
// report of it comes, before its report line is written. Like afterAnswer, they
// only ban.
func onReport() []heuristic {
return []heuristic{
byteLimits{},
}
}
// runAfterAnswer runs the heuristics of afterAnswer on the request, at the time
// it is called.
func (rq *request) runAfterAnswer(ctx context.Context) {
rq.runBanningHeuristics(ctx, afterAnswer())
}
// runHeuristics runs list, beforeLookup or afterLookup, on the request at now,
// and returns the first verdict, or nil when none gives one. The log line's
// heuristic and heuristic_figures name the heuristic that gave it, and give its
// figures. ctx is the request's own context.
func (rq *request) runHeuristics(
ctx context.Context, list []heuristic, now time.Time,
) *verdict {
name, v := rq.firstVerdict(ctx, list, now)
if v != nil {
rq.line.Heuristic = name
rq.line.HeuristicFigures = v.figures
}
return v
}
// runBanningHeuristics runs list, afterAnswer or onReport, on the request at
// the time it is called. The log line's after_answer_heuristic and
// after_answer_heuristic_figures name the heuristic that gave a verdict, and
// give its figures, so that heuristic and heuristic_figures still name the one
// that refused the request. ctx is the request's own context.
func (rq *request) runBanningHeuristics(ctx context.Context, list []heuristic) {
name, v := rq.firstVerdict(ctx, list, rq.h.now())
if v != nil {
rq.line.AfterAnswerHeuristic = name
rq.line.AfterAnswerHeuristicFigures = v.figures
}
}
// firstVerdict runs list on the request at now, in order, until a heuristic
// gives a verdict, and returns that heuristic's name and its verdict, or "" and
// nil when none gives one. ctx is the request's own context.
func (rq *request) firstVerdict(
ctx context.Context, list []heuristic, now time.Time,
) (string, *verdict) {
for _, each := range list {
v := each.check(ctx, rq, now)
if v != nil {
return each.name(), v
}
}
return "", nil
}
internal/discriminator/observe_test.go
-12
View File
@@ -14,18 +14,6 @@ import (
// observe is the value of SWW_MODE for observe mode. // observe is the value of SWW_MODE for observe mode.
const observe = "observe" const observe = "observe"
func TestObserveModeNamesTheHeuristicThatWouldHaveRefused(t *testing.T) {
t.Parallel()
s, _, _ := startWithClock(t, "", map[string]string{
mode: observe, denyNets: client,
})
line := s.get(client, http.StatusOK, requestlog.ActionForward)
wantWouldAction(t, line, requestlog.ActionDenied)
wantHeuristic(t, line, "deny_nets", `{"netblock": "`+client+`/32"}`)
}
func TestObserveModeForwardsWhatEnforceModeRefuses(t *testing.T) { func TestObserveModeForwardsWhatEnforceModeRefuses(t *testing.T) {
t.Parallel() t.Parallel()
internal/discriminator/ratelimits.go
-65
View File
@@ -1,65 +0,0 @@
package discriminator
// The heuristic rate_limits. It reads SWW_RATE_LIMIT_EXEMPT_NETS,
// SWW_RATE_LIMIT_EXEMPT_PATHS and SWW_BAN_RESPONSE, and the rate limits and
// biased thresholds through the limiter and limitPercentages.
import (
"context"
"time"
"sneak.berlin/go/smallwebwaf/internal/requestlog"
)
// rateLimits counts the request for the rate limits, unless
// countedByRateLimits exempts it, by the client's limit percentages, which it
// notes for the log line with the client's counts. A request that takes the
// client over a rate limit, as its limit percentage lowers it, breaks it: it is
// refused, and bans the client. A request exempt from the rate limits is exempt
// from the byte limits too. Its figures are the window, the count and the
// limit.
type rateLimits struct{}
func (rateLimits) name() string { return "rate_limits" }
func (rateLimits) check(_ context.Context, rq *request, now time.Time) *verdict {
rq.counted = rq.countedByRateLimits()
if !rq.counted {
return nil
}
rq.limitPercent, rq.bytesPercent = rq.limitPercentages()
rq.line.LimitPercent, rq.line.LimitPercentSetting = rq.limitPercent.logged()
rq.line.BytesPercent, rq.line.BytesPercentSetting = rq.bytesPercent.logged()
counts, hit, over := rq.h.limiter.Count(rq.h.clientGroup(rq.client), now,
rq.limitPercent.percent)
rq.line.Counts = counts
if !over {
return nil
}
rq.banForLimit(now, hit, rq.h.config.BanResponse)
return &verdict{action: requestlog.ActionRateLimited, figures: limitFigures(hit)}
}
// overAWholeRateLimit reports whether the heuristic rate_limits will refuse the
// request at now, whatever its client's limit percentages: the rate limits
// count it, and one more request from its client takes it over a whole rate
// limit. It counts nothing.
func (rq *request) overAWholeRateLimit(now time.Time) bool {
return rq.countedByRateLimits() &&
rq.h.limiter.OverARateLimit(rq.h.clientGroup(rq.client), now)
}
// countedByRateLimits reports whether the rate limits count the request: its
// client is not in SWW_RATE_LIMIT_EXEMPT_NETS, and its path is not exempt
// under SWW_RATE_LIMIT_EXEMPT_PATHS.
func (rq *request) countedByRateLimits() bool {
cfg := rq.h.config
return !isInside(rq.client, cfg.RateLimitExemptNets) &&
!pathExempt(rq.in, cfg.RateLimitExemptPaths)
}
internal/discriminator/ratelimits_test.go
-11
View File
@@ -72,17 +72,6 @@ func TestRateLimitRefusesBeforeTheApp(t *testing.T) {
} }
} }
func TestRateLimitRefusalNamesItsHeuristicWindowCountAndLimit(t *testing.T) {
t.Parallel()
s, _, _ := startWithClock(t, "", map[string]string{rateLimitPerMinute: "1"})
s.get(client, http.StatusOK, requestlog.ActionForward)
line := s.get(client, http.StatusForbidden, requestlog.ActionRateLimited)
wantHeuristic(t, line, "rate_limits", `{"window": "minute", "count": 2, "limit": 1}`)
}
func TestIPv6GroupPrefixSetsTheClientTheLimitsCount(t *testing.T) { func TestIPv6GroupPrefixSetsTheClientTheLimitsCount(t *testing.T) {
t.Parallel() t.Parallel()
internal/discriminator/refusallimit.go
-54
View File
@@ -1,54 +0,0 @@
package discriminator
// The heuristic refusal_limit. It reads SWW_ERROR_BURST_THRESHOLD and
// SWW_BAN_RESPONSE.
import (
"context"
"net/http"
"time"
"sneak.berlin/go/smallwebwaf/internal/requestlog"
)
// refusalLimit counts the request once it has been answered, if discriminator
// refused it after a rule file match, a trap path or a Core Rule Set match, and
// in observe mode if enforce mode would have: more than
// SWW_ERROR_BURST_THRESHOLD such refusals of the client within a minute break
// a limit, which bans the client. A client in SWW_ALLOW_NETS, which the
// heuristics skip, is not counted, and nothing is while the threshold is off.
// Its figures are the window, the count and the limit.
type refusalLimit struct{}
func (refusalLimit) name() string { return "refusal_limit" }
func (refusalLimit) check(_ context.Context, rq *request, now time.Time) *verdict {
cfg := rq.h.config
if cfg.ErrorBurstThreshold == 0 {
return nil
}
if !rq.attack && !rq.ruleBlocked && !rq.wafBlocked {
return nil
}
hit, over := rq.h.limiter.CountRefusal(rq.h.clientGroup(rq.client), now,
cfg.ErrorBurstThreshold)
if !over {
return nil
}
// What the client was sent, or in observe mode would have been.
status := rq.out.status
switch rq.line.WouldAction {
case requestlog.ActionRuleBlocked, requestlog.ActionWAFBlocked:
status = http.StatusForbidden
case requestlog.ActionBanned:
status = cfg.BanResponse
}
rq.banForLimit(now, hit, status)
return &verdict{action: requestlog.ActionBanned, figures: limitFigures(hit)}
}
internal/discriminator/reputation.go
+77 -3
View File
@@ -1,17 +1,91 @@
package discriminator package discriminator
// What the reputation heuristics share: blocklists, crowdsec, dnsbl and
// abuseipdb.
import ( import (
"context"
"time"
"sneak.berlin/go/smallwebwaf/internal/alerts" "sneak.berlin/go/smallwebwaf/internal/alerts"
"sneak.berlin/go/smallwebwaf/internal/bans" "sneak.berlin/go/smallwebwaf/internal/bans"
"sneak.berlin/go/smallwebwaf/internal/ratelimit"
"sneak.berlin/go/smallwebwaf/internal/reputation"
) )
// deny is the SWW_BLOCKLIST_ACTION and the SWW_REPUTATION_ACTION that // deny is the SWW_BLOCKLIST_ACTION and the SWW_REPUTATION_ACTION that
// refuses the requests of a client a source lists. // refuses the requests of a client a source lists.
const deny = "deny" const deny = "deny"
// blocklistDenied notes the blocklists that list the client, as
// noteListed does, and reports whether SWW_BLOCKLIST_ACTION, being deny,
// refuses the request. Being limit, it lowers the client's limits instead
// (see limitPercentages), and being log, it does nothing more.
func (rq *request) blocklistDenied() bool {
listedBy := rq.h.lists.ListedBy(rq.client)
rq.blocklisted = len(listedBy) > 0
rq.noteListed(listedBy, "listed by a blocklist")
return rq.blocklisted && rq.h.config.BlocklistAction == deny
}
// crowdSecBanned reports whether a decision of the CrowdSec decision list
// on the client is in force at now. If one is, it notes the list, as
// noteHit does, and bans the client until that decision ends.
func (rq *request) crowdSecBanned(now time.Time) bool {
decision, listed := rq.h.lists.CrowdSecDecision(rq.client, now)
if !listed {
return false
}
rq.noteHit(bans.ReputationHit{Source: rq.h.config.CrowdSecDecisionsURL},
"listed by the CrowdSec decision list")
rq.banForCrowdSec(now, decision)
return true
}
// dnsblDenied notes the DNSBL zones whose verdict lists the client, as
// noteListed does, and reports whether SWW_REPUTATION_ACTION, being
// deny, refuses the request. Being limit, it lowers the client's limits
// instead (see limitPercentages), and being log, it does nothing more. A
// zone without a verdict on the client is asked about it in the
// background, and the request does not wait for the answer. ctx is the
// request's own context.
func (rq *request) dnsblDenied(ctx context.Context) bool {
listedBy := rq.h.dnsbl.ListedBy(ctx, rq.client)
rq.dnsblListed = len(listedBy) > 0
rq.noteListed(listedBy, "listed by a DNSBL zone")
return rq.dnsblListed && rq.h.config.ReputationAction == deny
}
// abuseIPDBDenied notes AbuseIPDB, as noteHit does, with the score, when
// its score of the client is a hit, and reports whether
// SWW_REPUTATION_ACTION, being deny, refuses the request, as dnsblDenied
// does for a zone. While SWW_ABUSEIPDB_KEY is unset it does nothing. A
// client without a score is checked in the background, by the request's
// address, if its history counts an offence, and the request does not
// wait for the answer. The score is then used for each address of the
// client. ctx is the request's own context.
func (rq *request) abuseIPDBDenied(ctx context.Context) bool {
if rq.h.config.AbuseIPDBKey == "" {
return false
}
client := rq.h.clientGroup(rq.client)
held, _ := rq.h.limiter.Client(client)
offender := held.History.Offences != ratelimit.Offences{}
score, hit := rq.h.abuseIPDB.Hit(ctx, client, rq.client, offender)
if !hit {
return false
}
rq.abuseIPDBHit = true
rq.noteHit(bans.ReputationHit{Source: reputation.AbuseIPDBSource, Score: &score},
"scored by AbuseIPDB at or over SWW_ABUSEIPDB_MIN_SCORE")
return rq.h.config.ReputationAction == deny
}
// noteListed notes each of sources, the URLs of the blocklists or the // noteListed notes each of sources, the URLs of the blocklists or the
// DNSBL zones, their keys masked, that list the client, as noteHit does, // DNSBL zones, their keys masked, that list the client, as noteHit does,
// with reason. // with reason.
internal/discriminator/reputation_test.go
-50
View File
@@ -118,56 +118,6 @@ func TestEachBlocklistActionForAListedAddressAndAListedNetblock(t *testing.T) {
} }
} }
func TestReputationRefusalNamesItsHeuristicAndWhatListedTheClient(t *testing.T) {
t.Parallel()
for _, tc := range []struct {
heuristic string
env map[string]string
load func(*testing.T, *discriminator.Server)
figures string
}{
{
"blocklists",
map[string]string{blocklistURLs: dropURL, blocklistAction: actionDeny},
func(t *testing.T, server *discriminator.Server) {
t.Helper()
loadLists(t, server, map[string][]string{dropURL: {client}})
},
`{"lists": ["` + dropURL + `"]}`,
},
{
"dnsbl",
map[string]string{
dnsblZones: dnsblZone, dnsblResolver: noResolver,
reputationAction: actionDeny,
},
func(_ *testing.T, server *discriminator.Server) {
loadVerdicts(server, map[string][]string{client: {dnsblZone}})
},
`{"zones": ["` + dnsblZone + `"]}`,
},
{
"abuseipdb",
map[string]string{abuseIPDBKey: accountKey, reputationAction: actionDeny},
func(_ *testing.T, server *discriminator.Server) {
loadScores(server, map[string]int64{client: 80})
},
`{"score": 80, "min_score": 75}`,
},
} {
t.Run(tc.heuristic, func(t *testing.T) {
t.Parallel()
s, server, _ := startWithLookups(t, tc.env)
tc.load(t, server)
line := s.get(client, http.StatusForbidden, requestlog.ActionDenied)
wantHeuristic(t, line, tc.heuristic, tc.figures)
})
}
}
func TestBlocklistsComeAfterTheCountryListsAndSkipAllowNets(t *testing.T) { func TestBlocklistsComeAfterTheCountryListsAndSkipAllowNets(t *testing.T) {
t.Parallel() t.Parallel()
internal/discriminator/request.go
+85 -23
View File
@@ -160,20 +160,16 @@ 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 // 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 // the request through. The checks of checkClient decide: a request they refuse
// refuse is answered with SWW_BAN_RESPONSE, 403 for a block rule or the Core // is answered with SWW_BAN_RESPONSE, 403 for a block rule or the Core Rule Set,
// Rule Set, or 431 for the header limits. In observe mode nothing is refused, // or 431 for the header limits. In observe mode nothing is refused, and the log
// and the log line names what enforce mode would have done. ctx is the // line names what enforce mode would have done. ctx is the request's own context.
// request's own context.
func (rq *request) check(ctx context.Context) *refusal { func (rq *request) check(ctx context.Context) *refusal {
v := rq.checkClient(ctx) action := rq.checkClient(ctx)
if v == nil {
return nil
}
action := v.action
switch { switch {
case action == "":
return nil
case rq.h.config.Observe: case rq.h.config.Observe:
rq.line.WouldAction = action rq.line.WouldAction = action
@@ -187,21 +183,35 @@ func (rq *request) check(ctx context.Context) *refusal {
} }
} }
// checkClient runs the heuristics of beforeLookup on the request, then looks // checkClient runs the checks on the request's client, and returns the
// up the client's AS number and country, then runs those of afterLookup. It // action of the first that refuses the request, or "" when none does. A
// returns the first verdict, or nil when none gives one. A client in // client in SWW_ALLOW_NETS skips them, and is not looked up. For any
// SWW_ALLOW_NETS skips them all, and is not looked up. ctx is the request's // other client, SWW_DENY_NETS comes first, then a ban on its netblock,
// own context. // so that a client either refuses is not looked up, then the lookup of
func (rq *request) checkClient(ctx context.Context) *verdict { // its AS number and country, then the country lists, then the blocklists,
if isInside(rq.client, rq.h.config.AllowNets) { // then the CrowdSec decision list, which bans the client it lists, then
return nil // the DNSBL zones' verdicts, and then AbuseIPDB's score; a request any of
// them refuses is not counted for the rate limits. Then come the
// rate limits, unless the client is in SWW_RATE_LIMIT_EXEMPT_NETS or the
// request's path is exempt under SWW_RATE_LIMIT_EXEMPT_PATHS, so that
// every other request is counted, each of them by the client's limit
// percentages, then SWW_TRAP_PATHS, then the rule files, then the header
// limits, and last the Core Rule Set. A request exempt from the rate limits
// is exempt from the byte limits too. ctx is the request's own context.
func (rq *request) checkClient(ctx context.Context) string {
cfg := rq.h.config
if isInside(rq.client, cfg.AllowNets) {
return ""
} }
now := rq.h.now() now := rq.h.now()
v := rq.runHeuristics(ctx, beforeLookup(), now) if isInside(rq.client, cfg.DenyNets) {
if v != nil { return requestlog.ActionDenied
return v }
if rq.banned(now) {
return requestlog.ActionBanned
} }
rq.lookUp(ctx, now) rq.lookUp(ctx, now)
@@ -210,7 +220,59 @@ func (rq *request) checkClient(ctx context.Context) *verdict {
// again: a request counted at the time it arrived could be counted // again: a request counted at the time it arrived could be counted
// after a later one of its client's, which the rate limits would take // after a later one of its client's, which the rate limits would take
// for the clock set back. // for the clock set back.
return rq.runHeuristics(ctx, afterLookup(), rq.h.now()) now = rq.h.now()
if rq.countryDenied() {
return requestlog.ActionCountryDenied
}
if rq.blocklistDenied() {
return requestlog.ActionDenied
}
if rq.crowdSecBanned(now) {
return requestlog.ActionBanned
}
if rq.dnsblDenied(ctx) || rq.abuseIPDBDenied(ctx) {
return requestlog.ActionDenied
}
rq.counted = rq.countedByRateLimits()
if rq.counted {
rq.limitPercent, rq.bytesPercent = rq.limitPercentages()
rq.line.LimitPercent, rq.line.LimitPercentSetting = rq.limitPercent.logged()
rq.line.BytesPercent, rq.line.BytesPercentSetting = rq.bytesPercent.logged()
}
if rq.counted && rq.limitBroken(now) {
return requestlog.ActionRateLimited
}
if rq.trapPath(now) {
return requestlog.ActionBanned
}
action := rq.checkRules(now)
if action != "" {
return action
}
if rq.overHeaderLimits() {
return requestlog.ActionTooLarge
}
return rq.checkCoreRuleSet()
}
// countedByRateLimits reports whether the rate limits count the request: its
// client is not in SWW_RATE_LIMIT_EXEMPT_NETS, and its path is not exempt
// under SWW_RATE_LIMIT_EXEMPT_PATHS.
func (rq *request) countedByRateLimits() bool {
cfg := rq.h.config
return !isInside(rq.client, cfg.RateLimitExemptNets) &&
!pathExempt(rq.in, cfg.RateLimitExemptPaths)
} }
// pathExempt reports whether r is exempt under prefixes, // pathExempt reports whether r is exempt under prefixes,
internal/discriminator/requestlog_test.go
-43
View File
@@ -1,7 +1,6 @@
package discriminator_test package discriminator_test
import ( import (
"encoding/json"
"io" "io"
"math" "math"
"net/http" "net/http"
@@ -273,48 +272,6 @@ func wantTimings(t *testing.T, line logLine, want ...string) {
} }
} }
// wantHeuristic checks that line names heuristic as the one that refused the
// request, with figures, a JSON object. A heuristic of "" with figures "null" is
// a line that names none.
func wantHeuristic(t *testing.T, line logLine, heuristic, figures string) {
t.Helper()
if line.Heuristic != heuristic ||
!reflect.DeepEqual(line.HeuristicFigures, decodeFigures(t, figures)) {
t.Errorf("log line has heuristic %q with heuristic_figures %v, want %q with %s",
line.Heuristic, line.HeuristicFigures, heuristic, figures)
}
}
// wantAfterAnswerHeuristic checks after_answer_heuristic and
// after_answer_heuristic_figures as wantHeuristic checks heuristic and
// heuristic_figures.
func wantAfterAnswerHeuristic(t *testing.T, line logLine, heuristic, figures string) {
t.Helper()
if line.AfterAnswerHeuristic != heuristic ||
!reflect.DeepEqual(line.AfterAnswerHeuristicFigures, decodeFigures(t, figures)) {
t.Errorf("log line has after_answer_heuristic %q with "+
"after_answer_heuristic_figures %v, want %q with %s",
line.AfterAnswerHeuristic, line.AfterAnswerHeuristicFigures, heuristic, figures)
}
}
// decodeFigures decodes figures, a JSON object of a heuristic's figures, as
// the log line's figures are decoded.
func decodeFigures(t *testing.T, figures string) map[string]any {
t.Helper()
var decoded map[string]any
err := json.Unmarshal([]byte(figures), &decoded)
if err != nil {
t.Fatalf("decode %s: %v", figures, err)
}
return decoded
}
// microseconds is a timing in whole microseconds. // microseconds is a timing in whole microseconds.
func microseconds(milliseconds float64) int64 { func microseconds(milliseconds float64) int64 {
return int64(math.Round(milliseconds * 1000)) return int64(math.Round(milliseconds * 1000))
internal/discriminator/rulefiles.go
-55
View File
@@ -1,55 +0,0 @@
package discriminator
// The heuristic rule_files. It reads the rules of the rule files, which
// SWW_RULES_DIR and SWW_RULES_ENABLED name.
import (
"context"
"time"
"sneak.berlin/go/smallwebwaf/internal/bans"
"sneak.berlin/go/smallwebwaf/internal/requestlog"
"sneak.berlin/go/smallwebwaf/internal/rules"
)
// ruleFiles checks the request against the rules of the rule files at now,
// notes the ids of those it matches in the log line, and refuses the request
// when the last rule it matches refuses it: with ActionRuleBlocked for a block
// rule, and ActionBanned for a ban rule. A ban rule bans the client's netblock
// for a clear sign of attack, or in observe mode raises the alert for the ban
// it would have made. Either rule's match is noted as an offence, for the
// client's history. Its figures are the rule's id and action.
type ruleFiles struct{}
func (ruleFiles) name() string { return "rule_files" }
func (ruleFiles) check(_ context.Context, rq *request, now time.Time) *verdict {
matched := rq.h.rules.Match(rq.in)
for _, rule := range matched {
rq.line.RuleIDs = append(rq.line.RuleIDs, rule.ID)
rq.h.metrics.RuleMatched(rule.ID, rule.Action)
}
if len(matched) == 0 {
return nil
}
// Only the last rule matched can refuse the request.
last := matched[len(matched)-1]
figures := map[string]any{"rule_id": last.ID, "rule_action": last.Action}
switch last.Action {
case rules.ActionBlock:
rq.ruleBlocked = true
return &verdict{action: requestlog.ActionRuleBlocked, figures: figures}
case rules.ActionBan:
rq.attack = true
rq.banForAttack(now, bans.Notes{RuleID: last.ID, Target: last.Target})
return &verdict{action: requestlog.ActionBanned, figures: figures}
default:
return nil
}
}
internal/discriminator/rulefiles_test.go
-15
View File
@@ -93,21 +93,6 @@ func TestEachRuleAction(t *testing.T) {
s.get(client, http.StatusTooManyRequests, requestlog.ActionBanned) s.get(client, http.StatusTooManyRequests, requestlog.ActionBanned)
} }
func TestRuleRefusalNamesItsHeuristicAndTheRule(t *testing.T) {
t.Parallel()
s, _, _ := startWithClock(t, "", map[string]string{
rulesDir: writeRules(t, "noted path log ^/\n"+testRules),
})
line := s.request(client, "/blocked", http.StatusForbidden,
requestlog.ActionRuleBlocked)
wantHeuristic(t, line, "rule_files", `{"rule_id": "blocked", "rule_action": "block"}`)
line = s.request(client, "/.env", http.StatusForbidden, requestlog.ActionBanned)
wantHeuristic(t, line, "rule_files", `{"rule_id": "probe", "rule_action": "ban"}`)
}
func TestNextClearSignOfAttackAfterABanBansPermanently(t *testing.T) { func TestNextClearSignOfAttackAfterABanBansPermanently(t *testing.T) {
t.Parallel() t.Parallel()
internal/discriminator/rules.go
+64
View File
@@ -0,0 +1,64 @@
package discriminator
import (
"slices"
"time"
"sneak.berlin/go/smallwebwaf/internal/bans"
"sneak.berlin/go/smallwebwaf/internal/requestlog"
"sneak.berlin/go/smallwebwaf/internal/rules"
)
// trapPath reports whether the request asks for a path in
// SWW_TRAP_PATHS: its path as a path rule sees it, without the query,
// as sent or once percent-decoded, is one of them. Such a request is a
// clear sign of attack, as a ban rule's match is: it bans the client's
// netblock, or in observe mode raises the alert for the ban it would have
// made. The ban's notes give the path as sent.
func (rq *request) trapPath(now time.Time) bool {
path := rules.Path(rq.in)
if !slices.Contains(rq.h.config.TrapPaths, path) &&
!slices.Contains(rq.h.config.TrapPaths, rules.DecodeOnce(path)) {
return false
}
rq.attack = true
rq.banForAttack(now, bans.Notes{TrapPath: path})
return true
}
// checkRules checks the request against the rules of the rule files at
// now, notes the ids of those it matches in the log line, and returns the
// action of the rule that refuses it, ActionRuleBlocked for a block rule
// and ActionBanned for a ban rule, or "" when none does. A ban rule bans
// the client's netblock for a clear sign of attack, or in observe mode
// raises the alert for the ban it would have made. Either rule's match
// is noted as an offence, for the client's history.
func (rq *request) checkRules(now time.Time) string {
matched := rq.h.rules.Match(rq.in)
for _, rule := range matched {
rq.line.RuleIDs = append(rq.line.RuleIDs, rule.ID)
rq.h.metrics.RuleMatched(rule.ID, rule.Action)
}
if len(matched) == 0 {
return ""
}
// Only the last rule matched can refuse the request.
switch last := matched[len(matched)-1]; last.Action {
case rules.ActionBlock:
rq.ruleBlocked = true
return requestlog.ActionRuleBlocked
case rules.ActionBan:
rq.attack = true
rq.banForAttack(now, bans.Notes{RuleID: last.ID, Target: last.Target})
return requestlog.ActionBanned
default:
return ""
}
}
internal/discriminator/staticlists_test.go
-9
View File
@@ -104,15 +104,6 @@ func TestDenyNetsRefuseBeforeTheLookup(t *testing.T) {
} }
} }
func TestDenyNetsRefusalNamesItsHeuristicAndNetblock(t *testing.T) {
t.Parallel()
s, _, _ := startWithClock(t, "", map[string]string{denyNets: clientsNet})
line := s.get(client, http.StatusForbidden, requestlog.ActionDenied)
wantHeuristic(t, line, "deny_nets", `{"netblock": "`+clientsNet+`"}`)
}
func TestRequestRefusedByDenyNetsIsNotCounted(t *testing.T) { func TestRequestRefusedByDenyNetsIsNotCounted(t *testing.T) {
t.Parallel() t.Parallel()
internal/discriminator/trappaths.go
-39
View File
@@ -1,39 +0,0 @@
package discriminator
// The heuristic trap_paths. It reads SWW_TRAP_PATHS.
import (
"context"
"slices"
"time"
"sneak.berlin/go/smallwebwaf/internal/bans"
"sneak.berlin/go/smallwebwaf/internal/requestlog"
"sneak.berlin/go/smallwebwaf/internal/rules"
)
// trapPaths refuses a request for a path in SWW_TRAP_PATHS: its path as a
// path rule sees it, without the query, as sent or once percent-decoded, is one
// of them. Such a request is a clear sign of attack, as a ban rule's match is:
// it bans the client's netblock, or in observe mode raises the alert for the
// ban it would have made. The ban's notes give the path as sent, and so does
// its figure.
type trapPaths struct{}
func (trapPaths) name() string { return "trap_paths" }
func (trapPaths) check(_ context.Context, rq *request, now time.Time) *verdict {
path := rules.Path(rq.in)
if !slices.Contains(rq.h.config.TrapPaths, path) &&
!slices.Contains(rq.h.config.TrapPaths, rules.DecodeOnce(path)) {
return nil
}
rq.attack = true
rq.banForAttack(now, bans.Notes{TrapPath: path})
return &verdict{
action: requestlog.ActionBanned,
figures: map[string]any{"path": path},
}
}
internal/discriminator/trappaths_test.go
-10
View File
@@ -83,16 +83,6 @@ func TestTrapPathBansAsABanRuleDoes(t *testing.T) {
} }
} }
func TestTrapPathRefusalNamesItsHeuristicAndPath(t *testing.T) {
t.Parallel()
s, _, _ := startWithClock(t, "", map[string]string{trapPaths: trapPathList})
line := s.request(client, "/wp-login.php?redirect_to=x", http.StatusForbidden,
requestlog.ActionBanned)
wantHeuristic(t, line, "trap_paths", `{"path": "/wp-login.php"}`)
}
func TestTrapPathMatchesThePathDecodedOnce(t *testing.T) { func TestTrapPathMatchesThePathDecodedOnce(t *testing.T) {
t.Parallel() t.Parallel()
internal/lookup/file.go
+4 -14
View File
@@ -133,11 +133,8 @@ func (f *File) Watch(ctx context.Context) {
} }
if err != nil { if err != nil {
f.params.ProcessLog.Error( f.params.ProcessLog.Error("cannot watch the lookup database for replacements",
"cannot watch the lookup database for replacements", "error", err.Error())
"error",
err.Error(),
)
return return
} }
@@ -197,10 +194,7 @@ func (f *File) readAgain() {
f.params.Alerts.Raise(alerts.Alert{ f.params.Alerts.Raise(alerts.Alert{
Event: alerts.EventFileError, Event: alerts.EventFileError,
Reason: kept, Reason: kept,
Detail: map[string]any{ Detail: map[string]any{"file": f.params.Path, "error": err.Error()},
"file": f.params.Path,
"error": err.Error(),
},
}) })
f.params.ProcessLog.Error(kept, "error", err.Error()) f.params.ProcessLog.Error(kept, "error", err.Error())
@@ -218,11 +212,7 @@ func (f *File) use(reader *maxminddb.Reader) {
f.lastRead = f.params.Now() f.lastRead = f.params.Now()
f.mu.Unlock() f.mu.Unlock()
f.params.ProcessLog.Info( f.params.ProcessLog.Info("read the lookup database", "file", f.params.Path)
"read the lookup database",
"file",
f.params.Path,
)
} }
// read reads the lookup database at path. The whole file is read into // read reads the lookup database at path. The whole file is read into
internal/requestlog/requestlog.go
+4 -33
View File
@@ -19,34 +19,27 @@ const (
// ActionForward is a request discriminator allowed, which rproxy passes to // ActionForward is a request discriminator allowed, which rproxy passes to
// the app. // the app.
ActionForward = "forward" ActionForward = "forward"
// ActionTooLarge is a request over the header limits. // ActionTooLarge is a request over the header limits.
ActionTooLarge = "too_large" ActionTooLarge = "too_large"
// ActionRateLimited is a request refused because it took its client // ActionRateLimited is a request refused because it took its client
// over a rate limit, which bans the client. // over a rate limit, which bans the client.
ActionRateLimited = "rate_limited" ActionRateLimited = "rate_limited"
// ActionBanned is a request refused because a ban covers its client, // ActionBanned is a request refused because a ban covers its client,
// or because it matched a ban rule, asked for a trap path or the // or because it matched a ban rule, asked for a trap path or the
// CrowdSec decision list lists its client, each of which bans the // CrowdSec decision list lists its client, each of which bans the
// client. // client.
ActionBanned = "banned" ActionBanned = "banned"
// ActionRuleBlocked is a request refused because it matched a block // ActionRuleBlocked is a request refused because it matched a block
// rule. // rule.
ActionRuleBlocked = "rule_blocked" ActionRuleBlocked = "rule_blocked"
// ActionWAFBlocked is a request refused because the Core Rule Set // ActionWAFBlocked is a request refused because the Core Rule Set
// scored it at or over SWW_WAF_ANOMALY_THRESHOLD. // scored it at or over SWW_WAF_ANOMALY_THRESHOLD.
ActionWAFBlocked = "waf_blocked" ActionWAFBlocked = "waf_blocked"
// ActionDenied is a request refused because its client is in // ActionDenied is a request refused because its client is in
// SWW_DENY_NETS, in a blocklist while SWW_BLOCKLIST_ACTION is deny, // SWW_DENY_NETS, in a blocklist while SWW_BLOCKLIST_ACTION is deny,
// or listed by a DNSBL zone, or scored a hit by AbuseIPDB, while // or listed by a DNSBL zone, or scored a hit by AbuseIPDB, while
// SWW_REPUTATION_ACTION is deny. // SWW_REPUTATION_ACTION is deny.
ActionDenied = "denied" ActionDenied = "denied"
// ActionCountryDenied is a request refused for its client's country. // ActionCountryDenied is a request refused for its client's country.
ActionCountryDenied = "country_denied" ActionCountryDenied = "country_denied"
// ActionAdmin is a request discriminator answered at one of its own // ActionAdmin is a request discriminator answered at one of its own
@@ -138,16 +131,6 @@ type Line struct {
// ActionRuleBlocked, ActionWAFBlocked, or, in discriminator, ActionTooLarge // ActionRuleBlocked, ActionWAFBlocked, or, in discriminator, ActionTooLarge
// for the header limits. // for the header limits.
WouldAction string `json:"would_action,omitempty"` WouldAction string `json:"would_action,omitempty"`
// Heuristic is the name of the heuristic that refused the request, in
// observe mode too, and HeuristicFigures are the figures it acted on, by
// name.
Heuristic string `json:"heuristic,omitempty"`
HeuristicFigures map[string]any `json:"heuristic_figures,omitempty"`
// AfterAnswerHeuristic and AfterAnswerHeuristicFigures are the same for
// the heuristic that banned the client after discriminator answered the
// request.
AfterAnswerHeuristic string `json:"after_answer_heuristic,omitempty"`
AfterAnswerHeuristicFigures map[string]any `json:"after_answer_heuristic_figures,omitempty"` //nolint:lll // a struct tag cannot be split
// LimitPercent and LimitPercentSetting are, for a request the rate // LimitPercent and LimitPercentSetting are, for a request the rate
// limits counted whose client a biased threshold gives a percentage of // limits counted whose client a biased threshold gives a percentage of
// the rate limits below 100, that percentage and the setting that gave // the rate limits below 100, that percentage and the setting that gave
@@ -262,11 +245,7 @@ func FormatTime(t time.Time) string {
// Milliseconds is d in milliseconds, to the microsecond. // Milliseconds is d in milliseconds, to the microsecond.
func Milliseconds(d time.Duration) float64 { func Milliseconds(d time.Duration) float64 {
return float64( return float64(d.Microseconds()) / float64(time.Millisecond/time.Microsecond)
d.Microseconds(),
) / float64(
time.Millisecond/time.Microsecond,
)
} }
// NewProcessLogger returns the logger for the process's own messages: // NewProcessLogger returns the logger for the process's own messages:
@@ -274,25 +253,17 @@ func Milliseconds(d time.Duration) float64 {
// as a request line's, and instanceName, SWW_INSTANCE_NAME, as instance. // as a request line's, and instanceName, SWW_INSTANCE_NAME, as instance.
// It writes only the messages at level, SWW_LOG_LEVEL, or more severe; // It writes only the messages at level, SWW_LOG_LEVEL, or more severe;
// the request lines Write writes are never held back. // the request lines Write writes are never held back.
func NewProcessLogger( func NewProcessLogger(w io.Writer, instanceName string, level slog.Level) *slog.Logger {
w io.Writer,
instanceName string,
level slog.Level,
) *slog.Logger {
handler := slog.NewJSONHandler(w, &slog.HandlerOptions{ handler := slog.NewJSONHandler(w, &slog.HandlerOptions{
Level: level, Level: level,
ReplaceAttr: func(groups []string, attr slog.Attr) slog.Attr { ReplaceAttr: func(groups []string, attr slog.Attr) slog.Attr {
if attr.Key == slog.TimeKey && len(groups) == 0 { if attr.Key == slog.TimeKey && len(groups) == 0 {
return slog.String( return slog.String(slog.TimeKey, FormatTime(attr.Value.Time()))
slog.TimeKey,
FormatTime(attr.Value.Time()),
)
} }
return attr return attr
}, },
}) })
return slog.New(handler). return slog.New(handler).With("type", "process", "instance", instanceName)
With("type", "process", "instance", instanceName)
} }
script/publish
-54
View File
@@ -1,54 +0,0 @@
#!/bin/sh
# script/publish: build the image on the Docker host and push it to the
# registry under four tags: the UTC date (YYYY-MM-DD), the short commit
# hash, the branch name and latest. The build is script/docker's, so the
# tests and the linter run first. The host and the registry name are
# environment variables with defaults, for running it against another.
#
# The working tree must be clean: the hash tag names a commit, and an
# image built from uncommitted changes would carry a hash that does not
# describe it.
set -eu
SCRIPT_DIR="$(cd "$(dirname "$0")" && pwd -P)"
ROOT="$(cd "$SCRIPT_DIR/.." && pwd -P)"
: "${DOCKER_HOST:=ssh://root@fsn1app1}"
: "${PUBLISH_IMAGE:=git.eeqj.de/sneak/smallwebwaf}"
export DOCKER_HOST
main() {
cd "$ROOT"
# Own line: a failing command substitution inside an argument does
# not trip `set -e`.
changes="$(git status --porcelain)"
if [ -n "$changes" ]; then
echo "script/publish: the working tree is not clean; commit or stash first" >&2
exit 1
fi
date="$(date -u +%Y-%m-%d)"
hash="$(git rev-parse --short HEAD)"
branch="$(git rev-parse --abbrev-ref HEAD)"
if [ "$branch" = "HEAD" ]; then
echo "script/publish: detached HEAD; check out a branch first" >&2
exit 1
fi
# A tag is [A-Za-z0-9_.-]; a branch name such as feature/x is not.
branch="$(printf '%s' "$branch" | tr -c 'A-Za-z0-9_.-' '-')"
local_tag="$("$SCRIPT_DIR/projectname")"
"$SCRIPT_DIR/docker"
for tag in "$date" "$hash" "$branch" latest; do
docker tag "$local_tag" "$PUBLISH_IMAGE:$tag"
done
for tag in "$date" "$hash" "$branch" latest; do
docker push "$PUBLISH_IMAGE:$tag"
done
echo "pushed $PUBLISH_IMAGE with tags: $date $hash $branch latest"
}
main "$@"