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CrowdSec decision list fetched, kept, and its clients banned until the decision ends (closes #106)
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SWWAF_CROWDSEC_LAPI_URL and SWWAF_CROWDSEC_LAPI_KEY name an engine whose
decision list, <url>/v1/decisions, is fetched every minute with the key in
X-Api-Key, following no redirect, and kept as a blocklist is: used while a
fetch fails, and across restarts through reputation.json. Ban decisions on an
Ip or a Range end at the fetch time plus their duration. A listed client's
request is refused and bans its netblock with the cause crowdsec until the
decision ends; bans.json, ban notes and metrics take the cause.

Judgement call: fetched every minute, not a setting.
Judgement call: a crowdsec ban never lengthens a limit ban.
Judgement call: a lifted crowdsec ban is remade while its decision lasts.

Model: opus-5-5
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clawbot
2026-10-08 02:58:01 +00:00
parent 04e66d2069
commit b0476bd29a
20 changed files with 1700 additions and 292 deletions
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README.md
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@@ -26,11 +26,12 @@ Slack and ntfy, and remote log sending. So is the stage after that: the AS
number and country of every client, looked up through GeoJS or in the IPinfo
Lite database file, the byte limits, the biased thresholds, lower limits for the
AS numbers and countries you list, and the anomaly thresholds, alerts for
unusual traffic that refuse nothing. So are the first three parts of the stage
after that: the blocklists you name by URL, which it fetches and keeps, with a
file of AS numbers' percentages fetched the same way, the DNS blocklists (DNSBL
zones), which it asks about each client in the background, and AbuseIPDB, which
it asks in the background about each client that has committed an offence.
unusual traffic that refuse nothing. So is the stage after that: the blocklists
you name by URL, which it fetches and keeps, with a file of AS numbers'
percentages fetched the same way, the DNS blocklists (DNSBL zones), which it
asks about each client in the background, AbuseIPDB, which it asks in the
background about each client that has committed an offence, and the decision
list of a CrowdSec engine you run, which it fetches and keeps as a blocklist.
`smallwebwaf` passes each request to the app and the app's answer back,
unchanged, within its timeouts and size limits, works out each client's address,
looks up its AS number and country unless you switch that off, bans a client
@@ -39,26 +40,28 @@ you choose, with lower limits for the clients of the AS numbers and countries
you list, refuses a client that comes from a country you refuse or from a
network you refuse, refuses, limits or only notes a client a blocklist or a
DNSBL zone you name lists, or AbuseIPDB scores at or over the score you set,
lets the networks you choose through, checks each request against the rule files
and bans a client whose request is a clear sign of attack, keeps its bans, each
client's counters and history, GeoJS's answers, the last good copy of each list
it fetches, the DNSBL zones' verdicts, AbuseIPDB's scores and the AbuseIPDB
bans a client your CrowdSec engine's decision list lists until that decision
ends, lets the networks you choose through, checks each request against the rule
files and bans a client whose request is a clear sign of attack, keeps its bans,
each client's counters and history, GeoJS's answers, the last good copy of each
list it fetches, the DNSBL zones' verdicts, AbuseIPDB's scores and the AbuseIPDB
checks spent today in JSON files across restarts, takes in your edits of those
files, such as a ban you make, keep or lift, and of the rule files while it
runs, writes a JSON log line for every request, sends its log lines to a syslog
server too if you name one, sends an alert to a webhook, to Slack and to ntfy,
each if you name one, for each ban it makes or makes permanent, for traffic over
an anomaly threshold you set, for a client a blocklist, a DNSBL zone or
AbuseIPDB lists, for GeoJS failing, a list it cannot fetch, a DNSBL zone or
AbuseIPDB that fails or refuses a query and the day's AbuseIPDB checks used up,
for a rule file or state file with an error and for a replacement of the lookup
database it cannot read, serves Prometheus metrics to a scraper that holds the
metrics token, lets an admin who holds the admin token list, add and lift bans
and ask what it knows of a client, and in `observe` mode passes on the requests
it would refuse, logging what it would have done with them. It comes as the
image the app's own image is built on. The rest of the design comes after that,
in the order of the build order in [`SPEC.md`](SPEC.md). The survey of existing
tools that led to the design is in [`EVALUATION.md`](EVALUATION.md).
an anomaly threshold you set, for a client a blocklist, the CrowdSec decision
list, a DNSBL zone or AbuseIPDB lists, for GeoJS failing, a list it cannot
fetch, a DNSBL zone or AbuseIPDB that fails or refuses a query and the day's
AbuseIPDB checks used up, for a rule file or state file with an error and for a
replacement of the lookup database it cannot read, serves Prometheus metrics to
a scraper that holds the metrics token, lets an admin who holds the admin token
list, add and lift bans and ask what it knows of a client, and in `observe` mode
passes on the requests it would refuse, logging what it would have done with
them. It comes as the image the app's own image is built on. The rest of the
design comes after that, in the order of the build order in
[`SPEC.md`](SPEC.md). The survey of existing tools that led to the design is in
[`EVALUATION.md`](EVALUATION.md).
## Getting started
@@ -163,16 +166,17 @@ in `bin/state` unless `SWWAF_STATE_DIR` is set, and the default rule file of
and the requests or bytes counted in it, the client's percentage of that kind
of limit and the setting that gave it when a biased threshold lowered the
limit, the request that broke it, the client's AS number, AS name and country
once they are looked up, the blocklists, DNSBL zones and AbuseIPDB, with its
score, that listed the client when the ban was made, the netblock's requests
since it was first seen, how many of them the ban has refused, and how many
bans the netblock had before, for a broken limit, for a clear sign of attack
and by an admin. At most `SWWAF_MAX_BANS` bans `smallwebwaf` made are kept,
past, active and permanent; past that, the earliest such ban of the netblock
that has gone longest without a request is dropped first. The bans whose cause
is `admin`, those you make or keep, are kept besides, and never dropped.
`bans.json` shows the bans and their notes, a restart lifts none, and you
make, keep or lift a ban by editing it (see "State files" below).
once they are looked up, the blocklists, the CrowdSec decision list, DNSBL
zones and AbuseIPDB, with its score, that listed the client when the ban was
made, the netblock's requests since it was first seen, how many of them the
ban has refused, and how many bans the netblock had before, for a broken
limit, for a clear sign of attack, by an admin and for CrowdSec's decision. At
most `SWWAF_MAX_BANS` bans `smallwebwaf` made are kept, past, active and
permanent; past that, the earliest such ban of the netblock that has gone
longest without a request is dropped first. The bans whose cause is `admin`,
those you make or keep, are kept besides, and never dropped. `bans.json` shows
the bans and their notes, a restart lifts none, and you make, keep or lift a
ban by editing it (see "State files" below).
- Checks each request against the rules of the rule files (see "Rule files"
below) after the rate limits, and before its body is read. A `log` rule that
matches is noted in the log line; a `block` rule refuses the request with
@@ -214,6 +218,14 @@ in `bin/state` unless `SWWAF_STATE_DIR` is set, and the default rule file of
limit, the lowest of its percentages applying, as for a biased threshold, and
with `log` nothing more is done. Whatever the action, the request's log line
names the lists, and each raises an alert.
- Checks the client's own address against the decision list of the CrowdSec
engine `SWWAF_CROWDSEC_LAPI_URL` names, after the blocklists and before the
DNSBL zones (see "CrowdSec" below). A request from a client a decision in
force bans is refused with `SWWAF_BAN_RESPONSE` before its body is read, and
bans the client's netblock, as any ban covers it, until the decision ends,
with the cause `crowdsec`; the client's next requests are refused under that
ban. The request's log line names the list, and it raises an alert besides the
ban's. A client a blocklist refuses is not checked.
- Checks the client's own address against the DNSBL zones `SWWAF_DNSBL_ZONES`
names, after the blocklists and before the rate limits (see "DNS blocklists"
below), by the verdicts it keeps. A zone is asked about a client in the
@@ -226,7 +238,7 @@ in `bin/state` unless `SWWAF_STATE_DIR` is set, and the default rule file of
before their bodies are read; they are not counted for the rate limits, and
make no ban. With `log`, nothing more is done. Whatever the action, the
request's log line names the zones, and each raises an alert. A client a
blocklist refuses is not checked.
blocklist refuses, or the CrowdSec decision list bans, is not checked.
- Checks the client with AbuseIPDB while `SWWAF_ABUSEIPDB_KEY` is set, after the
DNSBL zones and before the rate limits (see "AbuseIPDB" below), by the scores
it keeps. Only a client whose history counts an offence is checked, so far one
@@ -235,38 +247,39 @@ in `bin/state` unless `SWWAF_STATE_DIR` is set, and the default rule file of
request waits for AbuseIPDB. A score at or over `SWWAF_ABUSEIPDB_MIN_SCORE` is
a hit, and `SWWAF_REPUTATION_ACTION` does with its client what it does with
one a DNSBL zone's verdict lists. The request's log line names AbuseIPDB, and
it raises an alert. A client a blocklist or a DNSBL zone refuses is not
checked.
it raises an alert. A client a blocklist or a DNSBL zone refuses, or the
CrowdSec decision list bans, is not checked.
- Checks the client's own address against the static lists, the three netblock
settings below, before anything else, its lookup included. A client in
`SWWAF_ALLOW_NETS` skips bans, the country lists, the blocklists, the DNSBL
zones, AbuseIPDB, the rate limits, the byte limits and the rule files, and is
not looked up; the timeouts and size limits still apply. A client in
`SWWAF_DENY_NETS` is refused with `SWWAF_BAN_RESPONSE` before its body is
read, and the request is not counted for the rate limits; an address in
`SWWAF_ALLOW_NETS` too is let through. A client in
`SWWAF_ALLOW_NETS` skips bans, the country lists, the blocklists, the CrowdSec
decision list, the DNSBL zones, AbuseIPDB, the rate limits, the byte limits
and the rule files, and is not looked up; the timeouts and size limits still
apply. A client in `SWWAF_DENY_NETS` is refused with `SWWAF_BAN_RESPONSE`
before its body is read, and the request is not counted for the rate limits;
an address in `SWWAF_ALLOW_NETS` too is let through. A client in
`SWWAF_RATE_LIMIT_EXEMPT_NETS` is neither counted nor refused by the rate
limits, and has no bytes counted by the byte limits; the country lists, the
rule files and bans still apply to it.
- In `observe` mode, with `SWWAF_MODE=observe`, refuses none of the requests
that `SWWAF_DENY_NETS`, a ban, the country lists, a blocklist, a DNSBL zone's
verdict, AbuseIPDB's score, a rate limit or a rule would refuse: it passes
them to the app, and their log lines name what `enforce` mode would have done
(see `would_action` in "Request log" below). The checks run, and requests and
bytes are counted, as in `enforce` mode, with three differences: neither a
broken rate limit or byte limit nor a `ban` rule makes a ban; a broken limit
does not set the client's counters back to zero, so each request over a rate
limit is logged as one that would be refused, and each whose bytes keep the
client over a byte limit as breaking it; and a request under a ban does not
make it permanent. As in `enforce` mode, the bytes counted are only those of
the requests `enforce` mode would have passed to the app. A ban it would have
made, or made permanent, raises the alert `enforce` mode would have raised,
marked as what would have happened (see "Alerts" below). The bans in
`bans.json` are kept, and refuse requests again when `smallwebwaf` next runs
in `enforce` mode, as long as they last. The timeouts and size limits still
apply, since they protect `smallwebwaf` and the app themselves, and a request
for one of `smallwebwaf`'s own endpoints without its token is still answered
`401`. It is for trying a configuration before enforcing it.
that `SWWAF_DENY_NETS`, a ban, the country lists, a blocklist, the CrowdSec
decision list, a DNSBL zone's verdict, AbuseIPDB's score, a rate limit or a
rule would refuse: it passes them to the app, and their log lines name what
`enforce` mode would have done (see `would_action` in "Request log" below).
The checks run, and requests and bytes are counted, as in `enforce` mode, with
three differences: neither a broken rate limit or byte limit, a `ban` rule nor
the CrowdSec decision list makes a ban; a broken limit does not set the
client's counters back to zero, so each request over a rate limit is logged as
one that would be refused, and each whose bytes keep the client over a byte
limit as breaking it; and a request under a ban does not make it permanent. As
in `enforce` mode, the bytes counted are only those of the requests `enforce`
mode would have passed to the app. A ban it would have made, or made
permanent, raises the alert `enforce` mode would have raised, marked as what
would have happened (see "Alerts" below). The bans in `bans.json` are kept,
and refuse requests again when `smallwebwaf` next runs in `enforce` mode, as
long as they last. The timeouts and size limits still apply, since they
protect `smallwebwaf` and the app themselves, and a request for one of
`smallwebwaf`'s own endpoints without its token is still answered `401`. It is
for trying a configuration before enforcing it.
- Answers `GET /_smallwebwaf/healthz` itself with `200` and `ok`, before any
check and without asking the app, for the image's health check.
- Answers `GET /_smallwebwaf/metrics` with its metrics (see "Metrics" below) for
@@ -286,12 +299,13 @@ in `bin/state` unless `SWWAF_STATE_DIR` is set, and the default rule file of
`SWWAF_LOG_REMOTE_URL` names one (see "Sending the log to a syslog server"
below).
- Sends an alert for each ban it makes or makes permanent, for a count over an
anomaly threshold, for a client a blocklist, a DNSBL zone or AbuseIPDB lists,
for GeoJS failing, a list it cannot fetch, a DNSBL zone or AbuseIPDB that
fails or refuses a query, and the day's AbuseIPDB checks used up, for a rule
file or state file with an error, and for a replacement of the lookup database
it cannot read, holding back repeats and, past an hourly limit, rolling the
rest into one summary, to each destination you name: as a JSON object to the
anomaly threshold, for a client a blocklist, the CrowdSec decision list, a
DNSBL zone or AbuseIPDB lists, for GeoJS failing, a list it cannot fetch, the
CrowdSec decision list among them, a DNSBL zone or AbuseIPDB that fails or
refuses a query, and the day's AbuseIPDB checks used up, for a rule file or
state file with an error, and for a replacement of the lookup database it
cannot read, holding back repeats and, past an hourly limit, rolling the rest
into one summary, to each destination you name: as a JSON object to the
webhook `SWWAF_ALERT_WEBHOOK_URL` names, as a message to the Slack incoming
webhook `SWWAF_ALERT_SLACK_WEBHOOK_URL` names, and as a message to the ntfy
topic `SWWAF_ALERT_NTFY_URL` names (see "Alerts" below).
@@ -370,9 +384,9 @@ effective settings are logged at start, unless `SWWAF_LOG_LEVEL` is `warn` or
- `SWWAF_REQUEST_MAX_BYTES` (default `100M`): the largest request body.
- `SWWAF_RESPONSE_MAX_BYTES` (default `5G`): the largest response body.
- `SWWAF_ALLOW_NETS` (default empty): netblocks whose clients skip bans, the
country lists, the blocklists, the DNSBL zones, AbuseIPDB, the rate limits,
the byte limits and the rule files, such as your monitoring or your own
networks.
country lists, the blocklists, the CrowdSec decision list, the DNSBL zones,
AbuseIPDB, the rate limits, the byte limits and the rule files, such as your
monitoring or your own networks.
- `SWWAF_RATE_LIMIT_EXEMPT_NETS` (default empty): netblocks whose clients the
rate limits and the byte limits do not apply to, such as a machine that talks
to the app all day.
@@ -495,6 +509,17 @@ effective settings are logged at start, unless `SWWAF_LOG_LEVEL` is `warn` or
from 0 to 100, that is a hit.
- `SWWAF_ABUSEIPDB_DAILY_BUDGET` (default `900`): the most checks made in a day,
in UTC, a whole number above zero. AbuseIPDB's free accounts may make 1,000.
- `SWWAF_CROWDSEC_LAPI_URL` (default unset): the local API of a CrowdSec engine
you run, whose decision list is fetched (see "CrowdSec" below), as an `http`
or `https` URL without a user or a fragment, such as `http://172.17.0.1:8080`.
While it is unset, no list is fetched. Set without `SWWAF_CROWDSEC_LAPI_KEY`,
it stops the start, and so does a URL whose decision list, the URL with
`v1/decisions` added to its path, `SWWAF_BLOCKLIST_URLS` or
`SWWAF_ASN_LIMIT_PERCENT_URL` names too.
- `SWWAF_CROWDSEC_LAPI_KEY` (default unset): the key the engine gave for
`smallwebwaf`, as `cscli bouncers add smallwebwaf` prints it. Set without
`SWWAF_CROWDSEC_LAPI_URL`, it stops the start. The settings logged at start
show `********` in its place.
- `SWWAF_REPUTATION_ACTION` (default `limit:25`): what is done with a client a
zone's verdict lists, or whose AbuseIPDB score is a hit, as
`SWWAF_BLOCKLIST_ACTION` is for a blocklist: `deny`, `limit:<percent>` or
@@ -516,7 +541,8 @@ effective settings are logged at start, unless `SWWAF_LOG_LEVEL` is `warn` or
limit or byte limit.
- `SWWAF_LIMIT_BAN_REPEAT_WINDOW` (default `24h`): a rate limit or byte limit
broken again within this time after a ban ended, other than one for a clear
sign of attack, bans for three times as long as that ban.
sign of attack or for CrowdSec's decision, bans for three times as long as
that ban.
- `SWWAF_MAX_BAN_DURATION` (default `7d`): a ban for a broken rate limit or byte
limit that would be longer is permanent instead.
- `SWWAF_ATTACK_BAN_DURATION` (default `7d`): the ban for a first clear sign of
@@ -668,7 +694,8 @@ and `SWWAF_ANOMALY_NET_V6_PREFIX` cannot be off.
Several limits are fixed rather than settings. At most 100,000 answers from
GeoJS are kept, for 7 days each, at most 20,000 anomaly counters, at most
100,000 verdicts of the DNSBL zones, with at most 1,000 queries to them under
way at once, and at most 100,000 scores of AbuseIPDB.
way at once, and at most 100,000 scores of AbuseIPDB, and the CrowdSec decision
list is fetched again a minute after it was last fetched or tried.
### Settings given as files
@@ -754,20 +781,22 @@ which every line has.
refused because its client is in `SWWAF_DENY_NETS`, in a blocklist while
`SWWAF_BLOCKLIST_ACTION` is `deny`, or listed by a DNSBL zone or AbuseIPDB
while `SWWAF_REPUTATION_ACTION` is `deny`, `banned` for one refused because a
ban covers its client or because it matched a `ban` rule, which bans its
client, `country_denied` for one refused for its client's country,
`rate_limited` for one that broke a rate limit and banned its client,
`rule_blocked` for one a `block` rule refused, `too_large` for a request or
response over its size limit, `timed_out` for one that ran out of time,
`upstream_error` when the app could not be reached or its answer broke off,
and `admin` for one `smallwebwaf` answered at its own endpoint.
ban covers its client, or because it matched a `ban` rule or the CrowdSec
decision list lists its client, either of which bans its client,
`country_denied` for one refused for its client's country, `rate_limited` for
one that broke a rate limit and banned its client, `rule_blocked` for one a
`block` rule refused, `too_large` for a request or response over its size
limit, `timed_out` for one that ran out of time, `upstream_error` when the app
could not be reached or its answer broke off, and `admin` for one
`smallwebwaf` answered at its own endpoint.
- `would_action` is there in `observe` mode for a request that
`SWWAF_DENY_NETS`, a ban, the country lists, a blocklist, a DNSBL zone's
verdict, AbuseIPDB's score, a rate limit or a rule would have refused in
`enforce` mode, and names the action that refusal would have had: `denied`,
`banned`, `country_denied`, `rate_limited` or `rule_blocked`. `action` then
names what was done: `forward` for a request passed to the app, and another
action, such as `too_large`, for one a size or time limit refused.
`SWWAF_DENY_NETS`, a ban, the country lists, a blocklist, the CrowdSec
decision list, a DNSBL zone's verdict, AbuseIPDB's score, a rate limit or a
rule would have refused in `enforce` mode, and names the action that refusal
would have had: `denied`, `banned`, `country_denied`, `rate_limited` or
`rule_blocked`. `action` then names what was done: `forward` for a request
passed to the app, and another action, such as `too_large`, for one a size or
time limit refused.
- `limit_percent` is there for a request the rate limits count whose client a
biased threshold, `SWWAF_BLOCKLIST_ACTION` for a blocklist that lists it, or
`SWWAF_REPUTATION_ACTION` for a DNSBL zone whose verdict lists it or an
@@ -785,11 +814,12 @@ which every line has.
health check, one from a client in `SWWAF_ALLOW_NETS` or
`SWWAF_RATE_LIMIT_EXEMPT_NETS`, one for a path that
`SWWAF_RATE_LIMIT_EXEMPT_PATHS` exempts, and one that `SWWAF_DENY_NETS`, a
ban, the country lists, a blocklist, a DNSBL zone's verdict or AbuseIPDB's
score refuse, or would refuse in `observe` mode. Its `minute_bytes`,
`hour_bytes` and `day_bytes` give the client's bytes in each window as the
byte limits count them, in the same way: for a request whose bytes they count,
with its own, once it has ended; for any other, those counted before it.
ban, the country lists, a blocklist, the CrowdSec decision list, a DNSBL
zone's verdict or AbuseIPDB's score refuse, or would refuse in `observe` mode.
Its `minute_bytes`, `hour_bytes` and `day_bytes` give the client's bytes in
each window as the byte limits count them, in the same way: for a request
whose bytes they count, with its own, once it has ended; for any other, those
counted before it.
- `rule_ids` is there for a request that matched rules of the rule files, and
lists their ids in the order they matched, up to the one that refused it.
- `limit_hit` is there for a request that broke a rate limit, or whose bytes
@@ -799,18 +829,22 @@ which every line has.
several. `offence` is then `limit`. A request whose bytes broke a byte limit
is not refused: its `action` is what it would have been otherwise, such as
`forward`.
- `reputation` is there for a request whose client a blocklist or a DNSBL zone's
verdict lists, or whose AbuseIPDB score is a hit, and gives the URLs of the
blocklists that list it, in the order `SWWAF_BLOCKLIST_URLS` names them, then
the zones whose verdict lists it, in the order `SWWAF_DNSBL_ZONES` names them,
then `abuseipdb`, whatever `SWWAF_BLOCKLIST_ACTION` and
`SWWAF_REPUTATION_ACTION` say. A zone whose verdict on the client has not come
yet, or was given `SWWAF_REPUTATION_CACHE_TTL` ago or more, is not named, nor
is AbuseIPDB for such a score. It is left out for a client the blocklists are
not checked for: one in `SWWAF_ALLOW_NETS`, and one `SWWAF_DENY_NETS`, a ban
or the country lists refuse first, or would in `observe` mode. The zones are
not checked either for a client a blocklist refuses, nor AbuseIPDB's score for
one a blocklist or a zone refuses, or would in `observe` mode.
- `reputation` is there for a request whose client a blocklist, the CrowdSec
decision list or a DNSBL zone's verdict lists, or whose AbuseIPDB score is a
hit, and gives the URLs of the blocklists that list it, in the order
`SWWAF_BLOCKLIST_URLS` names them, then the URL of the CrowdSec decision list
when a decision in force bans the client, then the zones whose verdict lists
it, in the order `SWWAF_DNSBL_ZONES` names them, then `abuseipdb`, whatever
`SWWAF_BLOCKLIST_ACTION` and `SWWAF_REPUTATION_ACTION` say. A zone whose
verdict on the client has not come yet, or was given
`SWWAF_REPUTATION_CACHE_TTL` ago or more, is not named, nor is AbuseIPDB for
such a score. It is left out for a client the blocklists are not checked for:
one in `SWWAF_ALLOW_NETS`, and one `SWWAF_DENY_NETS`, a ban or the country
lists refuse first, or would in `observe` mode. The CrowdSec decision list is
not checked either for a client a blocklist refuses, nor are the zones for one
a blocklist refuses or the decision list bans, nor AbuseIPDB's score for one a
blocklist or a zone refuses or the decision list bans, or would in `observe`
mode.
- `ban_expires` is there for a request that made a ban or was refused under one,
or in `observe` mode would have been refused under one, and gives when the ban
ends, in the same form as `time`, or `permanent`.
@@ -874,22 +908,23 @@ gives, as "Alert webhook schema" in [`SPEC.md`](SPEC.md) describes, and to
it, as below. An alert is for one of these events, and is sent when
`SWWAF_ALERT_EVENTS` names its event:
- `ban`: a ban `smallwebwaf` makes, for a broken rate limit or byte limit or a
clear sign of attack.
- `ban`: a ban `smallwebwaf` makes, for a broken rate limit or byte limit, a
clear sign of attack, or a client the CrowdSec decision list lists.
- `permanent_ban`: a permanent ban it makes, or a ban for a clear sign of attack
that a request made permanent.
- `anomaly`: a count of requests or bytes over an anomaly threshold, raised by
each request that ends with the count over it, in `observe` mode as in
`enforce` mode. It refuses and bans nothing.
- `reputation_hit`: a request whose client a blocklist or a DNSBL zone's verdict
lists, or whose AbuseIPDB score is a hit, one alert for each blocklist and
each zone that lists it, and one for AbuseIPDB, whatever
`SWWAF_BLOCKLIST_ACTION` and `SWWAF_REPUTATION_ACTION` say, in `observe` mode
as in `enforce` mode.
- `reputation_hit`: a request whose client a blocklist, the CrowdSec decision
list or a DNSBL zone's verdict lists, or whose AbuseIPDB score is a hit, one
alert for each blocklist and each zone that lists it, one for the decision
list, and one for AbuseIPDB, whatever `SWWAF_BLOCKLIST_ACTION` and
`SWWAF_REPUTATION_ACTION` say, in `observe` mode as in `enforce` mode.
- `source_failure`: GeoJS failing or refusing `smallwebwaf`, a fetch of a list
failing (see "Blocklists" below), a query to a DNSBL zone failing or refused
(see "DNS blocklists" below), or a check with AbuseIPDB failing or refused, or
the check that uses up the day's AbuseIPDB checks (see "AbuseIPDB" below).
failing (see "Blocklists" below), the CrowdSec decision list's among them (see
"CrowdSec" below), a query to a DNSBL zone failing or refused (see "DNS
blocklists" below), or a check with AbuseIPDB failing or refused, or the check
that uses up the day's AbuseIPDB checks (see "AbuseIPDB" below).
- `file_error`: a rule file edited while it runs that has an error, an edit of a
state file set aside as `<name>.bad`, a state file it could not write while
running, or a replacement of the lookup database it could not read, which it
@@ -939,7 +974,8 @@ is sent on one line:
"earlier_bans": {
"limit": 0,
"attack": 0,
"admin": 0
"admin": 0,
"crowdsec": 0
}
}
},
@@ -962,7 +998,8 @@ is sent on one line:
- `reason` is a short sentence; for a ban, the ban's `reason` in `bans.json`;
for an `anomaly`, what was counted over which threshold, such as
`requests per minute of the netblock 203.0.113.0/24 over the threshold of 1000`;
for a `reputation_hit`, `listed by a blocklist`, `listed by a DNSBL zone` or
for a `reputation_hit`, `listed by a blocklist`,
`listed by the CrowdSec decision list`, `listed by a DNSBL zone` or
`scored by AbuseIPDB at or over SWWAF_ABUSEIPDB_MIN_SCORE`.
- `detail` is what is particular to the event: for a ban, its `cause`, when it
ends as `ban_expires`, in the form the request log gives it, and its `notes`,
@@ -971,12 +1008,12 @@ is sent on one line:
`asn` and the `name` of the named netblock for `watch`, the `window`, `minute`
or `hour`, the `kind`, `requests` or `bytes`, the `count`, which is weighted
as the rate limits weigh theirs, and the `threshold`; for a `reputation_hit`,
the `source`, the URL of the blocklist, the zone or `abuseipdb`, and for
AbuseIPDB the `score`; for `source_failure`, the `source`, `geojs`, the URL of
the list, the zone or `abuseipdb`, the `error`, and for GeoJS, when it is
asked again, `asking_again_in`; for `file_error`, the `file`, which for an
edit set aside is the file it was renamed to, and the `error`, which for a
file that does not parse names where in it the error is.
the `source`, the URL of the blocklist or of the CrowdSec decision list, the
zone or `abuseipdb`, and for AbuseIPDB the `score`; for `source_failure`, the
`source`, `geojs`, the URL of the list, the zone or `abuseipdb`, the `error`,
and for GeoJS, when it is asked again, `asking_again_in`; for `file_error`,
the `file`, which for an edit set aside is the file it was renamed to, and the
`error`, which for a file that does not parse names where in it the error is.
- `suppressed_repeats` is how many repeats the cooldown held back before this
alert, and for a `summary`, those no other alert gives (see below).
@@ -1022,14 +1059,14 @@ and Slack this JSON object, shown indented; it is sent on one line:
```
An alert for the same event as the last one sent, on the same netblock, and for
a `reputation_hit` about the same blocklist, zone or AbuseIPDB, or for a
`file_error` about the same file, or for a `source_failure` about the same
source, or for an `anomaly` in the same scope, with the same netblock, AS number
or name, whatever its window and kind, less than `SWWAF_ALERT_COOLDOWN` after
it, is a repeat: it is held back and counted, and the next alert sent for them
gives that count as `suppressed_repeats`. As each hour of the clock, in UTC,
ends, the cooldowns that have run out are dropped, and the repeats they held
back, which no alert sent since has given, go in that hour's summary.
a `reputation_hit` about the same blocklist, decision list, zone or AbuseIPDB,
or for a `file_error` about the same file, or for a `source_failure` about the
same source, or for an `anomaly` in the same scope, with the same netblock, AS
number or name, whatever its window and kind, less than `SWWAF_ALERT_COOLDOWN`
after it, is a repeat: it is held back and counted, and the next alert sent for
them gives that count as `suppressed_repeats`. As each hour of the clock, in
UTC, ends, the cooldowns that have run out are dropped, and the repeats they
held back, which no alert sent since has given, go in that hour's summary.
Past `SWWAF_ALERT_MAX_PER_HOUR` alerts in an hour, the hour's other alerts are
held back and counted by event. An alert held back this way starts no cooldown.
@@ -1065,21 +1102,23 @@ with times in UTC.
- `bans.json`: every ban with its notes, indented to be read. A permanent ban's
`expires` is `null`. A ban's `cause` is `limit` for a broken rate limit or
byte limit or `attack` for a clear sign of attack, for a ban `smallwebwaf`
made, and `admin` for one you made or keep. Its `reason` is a short text: for
a ban `smallwebwaf` made, the limit broken, such as
`requests per minute over the limit of 1000` or
`bytes per hour over the limit of 21474836480`, or the rule that matched, such
as `matched the rule env-file`; for yours, what you wrote. Its `lifted` is
when you lifted it, and is left out until you do. The `kind` in the notes of a
ban for a broken limit is `requests` or `bytes`, what the limit is on. For a
limit a biased threshold lowered, the reason and the notes' `limit` give the
lowered limit, and the notes' `limit_percent` and `limit_percent_setting` the
client's percentage of that kind of limit and the setting that gave it. The
notes' `reputation` gives each blocklist, DNSBL zone or AbuseIPDB that listed
the client when the ban was made, as its `source`, named and ordered as in the
request log's `reputation`, with AbuseIPDB's `score` of the client. It is left
out when none did, and the example below shows it.
byte limit, `attack` for a clear sign of attack or `crowdsec` for a client the
CrowdSec decision list lists, for a ban `smallwebwaf` made, and `admin` for
one you made or keep. Its `reason` is a short text: for a ban `smallwebwaf`
made, the limit broken, such as `requests per minute over the limit of 1000`
or `bytes per hour over the limit of 21474836480`, the rule that matched, such
as `matched the rule env-file`, or the scenario that made CrowdSec's decision,
such as `CrowdSec's decision for crowdsecurity/ssh-bf`; for yours, what you
wrote. Its `lifted` is when you lifted it, and is left out until you do. The
`kind` in the notes of a ban for a broken limit is `requests` or `bytes`, what
the limit is on. For a limit a biased threshold lowered, the reason and the
notes' `limit` give the lowered limit, and the notes' `limit_percent` and
`limit_percent_setting` the client's percentage of that kind of limit and the
setting that gave it. The notes' `reputation` gives each blocklist, the
CrowdSec decision list, each DNSBL zone or AbuseIPDB that listed the client
when the ban was made, as its `source`, named and ordered as in the request
log's `reputation`, with AbuseIPDB's `score` of the client. It is left out
when none did, and the example below shows it.
- `clients.json`: each client's two buckets of requests in the minute, the hour
and the day, its two buckets of bytes in each, `minute_bytes`, `hour_bytes`
and `day_bytes`, and its history: when it was first and last seen, its AS
@@ -1091,20 +1130,20 @@ with times in UTC.
`grep` shows everything about one.
- `lookups.json`: GeoJS's answers, one to a line, each with the client's AS
number, AS name and country, when GeoJS gave it and when it was last used.
- `reputation.json`: each list fetched from a URL (see "Blocklists" below),
indented to be read, under `lists`: its `url`, when it was last `tried`, the
fetch failed or not, and its last good copy: when that was `fetched`, and its
`lines`, as fetched, comment lines included, each on a line of its own, both
left out while no fetch of it has succeeded; and under `verdicts`, each
verdict of a DNSBL zone still in use (see "DNS blocklists" below): its `zone`,
the `client`'s address, whether the zone `listed` the client, and when the
zone gave it, `fetched`; and under `abuseipdb` (see "AbuseIPDB" below), the
`day`, in UTC, whose checks it counts, left out before the first, the checks
`spent` that day, and under `scores`, each score of AbuseIPDB still in use:
the `client`, its IPv4 address as a /32 or its IPv6 group, its `score`, and
when AbuseIPDB gave it, `fetched`. As the file is read, the lists the settings
no longer name, and the verdicts of the zones they no longer name, are
dropped.
- `reputation.json`: each list fetched from a URL (see "Blocklists" and
"CrowdSec" below), indented to be read, under `lists`: its `url`, when it was
last `tried`, the fetch failed or not, and its last good copy: when that was
`fetched`, and its `lines`, as fetched, comment lines included, each on a line
of its own, both left out while no fetch of it has succeeded; and under
`verdicts`, each verdict of a DNSBL zone still in use (see "DNS blocklists"
below): its `zone`, the `client`'s address, whether the zone `listed` the
client, and when the zone gave it, `fetched`; and under `abuseipdb` (see
"AbuseIPDB" below), the `day`, in UTC, whose checks it counts, left out before
the first, the checks `spent` that day, and under `scores`, each score of
AbuseIPDB still in use: the `client`, its IPv4 address as a /32 or its IPv6
group, its `score`, and when AbuseIPDB gave it, `fetched`. As the file is
read, the lists the settings no longer name, and the verdicts of the zones
they no longer name, are dropped.
- `alerts.json`: the state of the alerts (see "Alerts" above), indented to be
read: under `cooldowns`, for each event and netblock, with the `source` too
for a `reputation_hit`, or event and `file` or `source`, or for an `anomaly`,
@@ -1172,7 +1211,8 @@ at its default of `limit:25`, lowered to a quarter:
"earlier_bans": {
"limit": 0,
"attack": 0,
"admin": 0
"admin": 0,
"crowdsec": 0
}
}
}
@@ -1211,11 +1251,11 @@ counter's `netblock`, unless it counts an AS number or the whole service, its
window in which it has requests or bytes; a list's `url`, `fetched` or `lines`,
which is `[]` for an empty list; a verdict's `zone`, `client`, `listed`, which
is `false` for a client the zone does not list, or `fetched`. So does a ban
whose `cause` is not `limit`, `attack` or `admin`, alerts waiting for a
destination that is not `webhook`, `slack` or `ntfy`, an anomaly counter whose
`scope` is not `client`, `net`, `asn`, `total` or `watch`, and a copy of a list
with a line that would make its fetch fail. An answer's `asn` or `as_name` left
out reads as empty.
whose `cause` is not `limit`, `attack`, `admin` or `crowdsec`, alerts waiting
for a destination that is not `webhook`, `slack` or `ntfy`, an anomaly counter
whose `scope` is not `client`, `net`, `asn`, `total` or `watch`, and a copy of a
list with a line that would make its fetch fail. An answer's `asn` or `as_name`
left out reads as empty.
While it runs, `smallwebwaf` watches `SWWAF_STATE_DIR` and takes in your edit of
a state file as soon as you save it: what the file then holds replaces what
@@ -1240,7 +1280,7 @@ and its `expires`, `null` for a ban that never ends; its `reason` and its
written so at the file's next write. A ban whose `cause` is `admin` is never
dropped and does not count toward `SWWAF_MAX_BANS`. A ban whose `cause` is
`attack` becomes permanent at the first request it refuses; one whose `cause` is
`admin` does not. This `bans.json` bans `203.0.113.0/24` for good:
`admin` or `crowdsec` does not. This `bans.json` bans `203.0.113.0/24` for good:
```json
{
@@ -1369,11 +1409,11 @@ scraped, and keeps this one as `exported_instance` unless the scrape sets
and `kind`, `requests` for a rate limit or `bytes` for a byte limit,
`smallwebwaf_size_and_time_limit_hits_total` by `limit`, the setting whose
limit was passed, `smallwebwaf_offences_total` by `kind`, and
`smallwebwaf_bans_made_total` by `cause`, `limit`, `attack` or `admin`, the
last for the bans you add through `POST /_smallwebwaf/bans`, and those whose
`cause` is `admin` that you add to `bans.json` while `smallwebwaf` runs;
`smallwebwaf_active_bans` and `smallwebwaf_permanent_bans`, neither of which
counts a lifted ban.
`smallwebwaf_bans_made_total` by `cause`, `limit`, `attack`, `admin` or
`crowdsec`, `admin` for the bans you add through `POST /_smallwebwaf/bans`,
and those whose `cause` is `admin` that you add to `bans.json` while
`smallwebwaf` runs; `smallwebwaf_active_bans` and
`smallwebwaf_permanent_bans`, neither of which counts a lifted ban.
- `smallwebwaf_rule_matches_total`: the requests that matched each rule, by
`rule_id` and `action`, the rule's own; and `smallwebwaf_rules_loaded`: the
rules read from the rule files.
@@ -1402,8 +1442,9 @@ scraped, and keeps this one as `exported_instance` unless the scrape sets
`smallwebwaf_lookup_database_read_failures_total`: the replacements of it that
could not be read.
- By `source`, the URL of each list `SWWAF_BLOCKLIST_URLS` or
`SWWAF_ASN_LIMIT_PERCENT_URL` names: `smallwebwaf_reputation_hits_total`: the
requests whose client the blocklist lists, a series that comes with the first;
`SWWAF_ASN_LIMIT_PERCENT_URL` names, and of the CrowdSec decision list:
`smallwebwaf_reputation_hits_total`: the requests whose client the blocklist
or the decision list lists, a series that comes with the first;
`smallwebwaf_reputation_failures_total`: the fetches of the list that failed;
and `smallwebwaf_reputation_last_fetch_timestamp_seconds`: when the copy of it
in use was fetched, `0` while there is none.
@@ -1633,7 +1674,8 @@ For each request `smallwebwaf`:
the deny list or currently banned;
- looks up its AS number and country, and refuses it if that country is denied,
or is not among the only ones allowed;
- checks it against the blocklists, and for a cached reputation verdict;
- checks it against the blocklists, bans it if the CrowdSec decision list lists
it, and checks it for a cached reputation verdict;
- picks the client's limit percentage from those;
- checks the minute, hour and day request counters against the limits, and bans
the client if it breaks one;
@@ -1944,6 +1986,59 @@ the metrics nor `reputation.json` hold it. Given as a file, with
`SWWAF_ABUSEIPDB_KEY_FILE`, it can be kept out of the app's reach (see "Settings
given as files" above).
## CrowdSec
While `SWWAF_CROWDSEC_LAPI_URL` names the local API of a CrowdSec engine you
run, `smallwebwaf` fetches the engine's decision list, at that URL with
`v1/decisions` added to its path, with `SWWAF_CROWDSEC_LAPI_KEY`, a key the
engine gave, such as `cscli bouncers add smallwebwaf` makes. This is how a list
kept for a whole fleet of hosts can reach `smallwebwaf` without it depending on
CrowdSec. It is unset by default, for the reason no blocklist is named, and
since it needs an engine of your own.
The list is fetched again a minute after it was last fetched or tried, the fetch
failed or not, and is kept as a blocklist is (see "Blocklists" above): its last
good copy, the engine's answer as it came, stays in use while a fetch fails, and
`reputation.json` keeps it with the time it was fetched, so that a restart keeps
it in use too. A fetch fails when the engine answers other than `200`, a
redirect included, such as `403` for a key it does not know, when it does not
finish within a minute, when the answer is longer than 16 MiB or is not a JSON
list of decisions, or when a decision to ban gives a value that is not an
address or a netblock, or a `duration` that does not read. A failure is counted,
logged and raised as a `source_failure` alert, held back as a repeat within
`SWWAF_ALERT_COOLDOWN`.
The decisions of the type `ban` on an address or a netblock, the scopes `Ip` and
`Range`, are used; any other, such as one to show a captcha or one on a country,
is left out. A decision bans until its `duration`, the time it had left as the
engine answered, has passed since the fetch, so that one that has ended no
longer bans, even while the copy in use still holds it because the engine cannot
be reached.
A client in `SWWAF_ALLOW_NETS` is not checked, nor is one a blocklist refuses.
Any other is checked by its own address after the blocklists. A request from a
client a decision in force bans is refused with `SWWAF_BAN_RESPONSE`, and bans
the client's netblock, as any ban covers it, until that decision ends, the one
that ends last if several ban the client. The ban's cause is `crowdsec`, and its
reason names the decision's scenario. Only a client that sends a request is
banned, so that a long list does not fill `bans.json`. Such a ban counts toward
`SWWAF_MAX_BANS`, is never made permanent, and does not make the netblock's next
ban for a broken limit longer. The request's log line and the ban's notes name
the list by its URL, as they name a blocklist, and the request raises a
`reputation_hit` alert besides the ban's.
A ban you lift while its decision is in force is followed by another at the
client's next request. To let a client in, delete its decision in CrowdSec, such
as with `cscli decisions delete --ip 203.0.113.9`, and lift the ban once the
list has been fetched again, a minute or so later. A ban made for a decision
deleted in CrowdSec otherwise lasts until that decision would have ended.
The key is sent to the engine in the `X-Api-Key` header, and nowhere else. The
settings logged at start show `********` in its place, and neither the log, the
alerts, the metrics nor `reputation.json` hold it. Given as a file, with
`SWWAF_CROWDSEC_LAPI_KEY_FILE`, it can be kept out of the app's reach (see
"Settings given as files" above).
## How the code is laid out
- `cmd/smallwebwaf`: the binary, which only calls `internal/smallwebwaf`.
@@ -1957,15 +2052,16 @@ given as files" above).
standard library's `httputil.ReverseProxy` within the timeouts and size
limits, and writes the request's log line. Its `check` method is where a
request is refused before anything reaches the app: for `SWWAF_DENY_NETS`, for
a ban, for the country lists, for a blocklist, for a DNSBL zone's verdict, for
AbuseIPDB's score, for a rate limit, which bans the client, for a `block` or
`ban` rule, the latter banning the client, and for an announced body over the
size limit; in `observe` mode, only for the size limit, with what it would
have refused for noted in the log line. A request under `/_smallwebwaf/` that
`check` lets through is answered by `answerAdmin` instead of reaching the app.
Once the answer to a request passed to the app has ended, `countBytes` counts
its bytes for the byte limits, and once any request but the health check has
ended, `countAnomalies` counts it for the anomaly thresholds.
a ban, for the country lists, for a blocklist, for the CrowdSec decision list,
which bans the client, for a DNSBL zone's verdict, for AbuseIPDB's score, for
a rate limit, which bans the client, for a `block` or `ban` rule, the latter
banning the client, and for an announced body over the size limit; in
`observe` mode, only for the size limit, with what it would have refused for
noted in the log line. A request under `/_smallwebwaf/` that `check` lets
through is answered by `answerAdmin` instead of reaching the app. Once the
answer to a request passed to the app has ended, `countBytes` counts its bytes
for the byte limits, and once any request but the health check has ended,
`countAnomalies` counts it for the anomaly thresholds.
- `internal/metrics`: the metrics, counted as the other parts tell it what
happened, and served in the Prometheus text format.
- `internal/bans`: the ban ledger: each netblock's bans with their notes, how
@@ -1978,14 +2074,15 @@ given as files" above).
client's history and to the notes of its bans; or in the lookup database,
which it reads again when the file is replaced. `internal/lookup/lookuptest`
writes lookup databases for the tests.
- `internal/reputation`: fetches the blocklists and the file
`SWWAF_ASN_LIMIT_PERCENT_URL` names as they are due, keeps the last good copy
of each, and tells which blocklists list an address and what percentage the
file gives an AS number; asks the DNSBL zones about clients in the background,
through the standard library's resolver, keeps their verdicts, and tells which
zones' verdicts list an address; and checks clients with AbuseIPDB in the
background, keeps their scores and the checks spent today, and tells whether a
client's score is a hit.
- `internal/reputation`: fetches the blocklists, the file
`SWWAF_ASN_LIMIT_PERCENT_URL` names and the CrowdSec decision list as they are
due, keeps the last good copy of each, and tells which blocklists list an
address, what percentage the file gives an AS number, and which decision of
the decision list bans an address; asks the DNSBL zones about clients in the
background, through the standard library's resolver, keeps their verdicts, and
tells which zones' verdicts list an address; and checks clients with AbuseIPDB
in the background, keeps their scores and the checks spent today, and tells
whether a client's score is a hit.
- `internal/ratelimit`: the table of clients: counts each client's requests and
bytes, tells when they take it over a rate limit or a byte limit, and keeps
each client's history.
internal/alerts/alerts.go
+3 -2
View File
@@ -46,8 +46,9 @@ const (
EventAnomaly = "anomaly"
// EventWAFBlock comes with the Core Rule Set; nothing raises it yet.
EventWAFBlock = "waf_block"
// EventReputationHit is a request whose client a blocklist or a DNSBL
// zone lists, or whose AbuseIPDB score is a hit.
// EventReputationHit is a request whose client a blocklist, the
// CrowdSec decision list or a DNSBL zone lists, or whose AbuseIPDB score
// is a hit.
EventReputationHit = "reputation_hit"
// EventSourceFailure is GeoJS failing or refusing smallwebwaf, a fetch
// of a list failing, a query to a DNSBL zone or a check with AbuseIPDB
internal/bans/bans.go
+87 -38
View File
@@ -1,8 +1,9 @@
// Package bans is the ban ledger: the bans smallwebwaf makes on the
// netblocks of clients that break a rate limit or a byte limit or show a
// clear sign of attack, and those an admin makes, with their notes, as
// the "Bans" section of SPEC.md describes. The bans are kept in memory,
// and written to bans.json and read from it by the state package.
// netblocks of clients that break a rate limit or a byte limit, show a
// clear sign of attack or are listed by the CrowdSec decision list, and
// those an admin makes, with their notes, as the "Bans" section of SPEC.md
// describes. The bans are kept in memory, and written to bans.json and
// read from it by the state package.
package bans
import (
@@ -26,6 +27,9 @@ const (
// CauseAdmin is a ban an admin made, or one smallwebwaf made that an
// admin keeps. It is never dropped.
CauseAdmin = "admin"
// CauseCrowdSec is a ban smallwebwaf made for a client the CrowdSec
// decision list lists. It ends when CrowdSec's decision does.
CauseCrowdSec = "crowdsec"
)
// repeatFactor is how many times as long as the netblock's last ban a ban
@@ -40,9 +44,9 @@ type Rules struct {
// LimitBanDuration is how long a first ban for a broken limit lasts.
LimitBanDuration time.Duration
// LimitBanRepeatWindow is how soon after the end of the netblock's
// ban that ended last, other than one for a clear sign of attack, a
// broken limit counts as a repeat, which bans for repeatFactor times as
// long as that ban.
// ban that ended last, other than one for a clear sign of attack or for
// CrowdSec's decision, a broken limit counts as a repeat, which bans for
// repeatFactor times as long as that ban.
LimitBanRepeatWindow time.Duration
// MaxBanDuration is the longest ban for a broken limit; one that would
// be longer is permanent instead.
@@ -63,10 +67,11 @@ type Ban struct {
Start time.Time
// Expires is when the ban ends, zero for a permanent ban.
Expires time.Time
// Cause is CauseLimit, CauseAttack or CauseAdmin.
// Cause is CauseLimit, CauseAttack, CauseAdmin or CauseCrowdSec.
Cause string
// Reason is a short text: for a ban smallwebwaf made, the limit broken
// or the rule that matched; for an admin's, what the admin wrote.
// Reason is a short text: for a ban smallwebwaf made, the limit broken,
// the rule that matched or the scenario of CrowdSec's decision; for an
// admin's, what the admin wrote.
Reason string
// Lifted is when an admin lifted the ban, zero while no admin has. A
// lifted ban refuses nothing, and does not make the netblock's next
@@ -123,7 +128,8 @@ type Notes struct {
// log's reputation names them. It is left out when none did.
Reputation []ReputationHit `json:"reputation,omitempty"`
// Request is the request that broke the limit, or whose bytes broke
// it, or that was the clear sign of attack.
// it, that was the clear sign of attack, or that came from a client the
// CrowdSec decision list lists.
Request Request `json:"request"`
// Requests is how many requests the netblock has sent since it was
// first seen, and Refused how many of them the ban has refused so
@@ -136,9 +142,10 @@ type Notes struct {
}
// ReputationHit is a reputation source that listed a client, as a
// reputation_hit alert's detail gives it: Source is the blocklist's URL,
// the DNSBL zone with its key masked, or "abuseipdb", and Score, for
// AbuseIPDB alone, its score of the client.
// reputation_hit alert's detail gives it: Source is the URL of the
// blocklist or of the CrowdSec decision list, the DNSBL zone with its key
// masked, or "abuseipdb", and Score, for AbuseIPDB alone, its score of the
// client.
type ReputationHit struct {
Source string `json:"source"`
Score *int64 `json:"score,omitempty"`
@@ -146,9 +153,10 @@ type ReputationHit struct {
// EarlierBans counts a netblock's bans before a ban, by cause.
type EarlierBans struct {
Limit int `json:"limit"`
Attack int `json:"attack"`
Admin int `json:"admin"`
Limit int `json:"limit"`
Attack int `json:"attack"`
Admin int `json:"admin"`
CrowdSec int `json:"crowdsec"`
}
// Request is a request in a ban's notes. Each text is cut to 256 bytes.
@@ -276,7 +284,8 @@ func activeBan(bans []Ban, now time.Time) *Ban {
// BanForLimit bans netblock at now for a broken limit, with notes, and
// returns the ban, and true. A first ban lasts LimitBanDuration. A ban
// made within LimitBanRepeatWindow after the netblock's ban that ended
// last, other than one for a clear sign of attack or a lifted one, lasts
// last, other than one for a clear sign of attack or for CrowdSec's
// decision, or a lifted one, lasts
// repeatFactor times as long as that one. A ban that would be longer
// than MaxBanDuration is permanent instead. If a ban on netblock is still
// active, as when two of its requests break a limit at once, that ban is
@@ -287,7 +296,7 @@ func activeBan(bans []Ban, now time.Time) *Ban {
func (l *Ledger) BanForLimit(
netblock netip.Prefix, now time.Time, notes Notes,
) (Ban, bool) {
return l.ban(netblock, now, CauseLimit, limitReason(notes), notes, true)
return l.ban(netblock, now, time.Time{}, CauseLimit, limitReason(notes), notes, true)
}
// WouldBanForLimit returns what BanForLimit would, without making the ban:
@@ -295,7 +304,7 @@ func (l *Ledger) BanForLimit(
func (l *Ledger) WouldBanForLimit(
netblock netip.Prefix, now time.Time, notes Notes,
) (Ban, bool) {
return l.ban(netblock, now, CauseLimit, limitReason(notes), notes, false)
return l.ban(netblock, now, time.Time{}, CauseLimit, limitReason(notes), notes, false)
}
// BanForAttack bans netblock at now for a clear sign of attack, with
@@ -306,7 +315,7 @@ func (l *Ledger) WouldBanForLimit(
func (l *Ledger) BanForAttack(
netblock netip.Prefix, now time.Time, notes Notes,
) (Ban, bool) {
return l.ban(netblock, now, CauseAttack, attackReason(notes), notes, true)
return l.ban(netblock, now, time.Time{}, CauseAttack, attackReason(notes), notes, true)
}
// WouldBanForAttack returns what BanForAttack would, without making the
@@ -314,12 +323,35 @@ func (l *Ledger) BanForAttack(
func (l *Ledger) WouldBanForAttack(
netblock netip.Prefix, now time.Time, notes Notes,
) (Ban, bool) {
return l.ban(netblock, now, CauseAttack, attackReason(notes), notes, false)
return l.ban(netblock, now, time.Time{}, CauseAttack, attackReason(notes), notes,
false)
}
// WouldBePermanent reports whether a ban on netblock for cause, CauseLimit
// or CauseAttack, made at now would be permanent, as BanForLimit or
// BanForAttack would make it. It works out nothing else of the ban.
// BanForCrowdSec bans netblock at now until expires, when CrowdSec's
// decision on the client ends, with notes, and returns the ban, and
// whether it made it, as BanForLimit does. Its reason is "CrowdSec's
// decision for <scenario>", the scenario that made the decision.
func (l *Ledger) BanForCrowdSec(
netblock netip.Prefix, now, expires time.Time, scenario string, notes Notes,
) (Ban, bool) {
return l.ban(netblock, now, expires, CauseCrowdSec, crowdSecReason(scenario), notes,
true)
}
// WouldBanForCrowdSec returns what BanForCrowdSec would, without making
// the ban: what observe mode would have done.
func (l *Ledger) WouldBanForCrowdSec(
netblock netip.Prefix, now, expires time.Time, scenario string, notes Notes,
) (Ban, bool) {
return l.ban(netblock, now, expires, CauseCrowdSec, crowdSecReason(scenario), notes,
false)
}
// WouldBePermanent reports whether a ban on netblock for cause, CauseLimit,
// CauseAttack or CauseCrowdSec, made at now would be permanent, as
// BanForLimit, BanForAttack or BanForCrowdSec would make it. It works out
// nothing else of the ban. A ban for CrowdSec's decision is never
// permanent: it ends with the decision.
func (l *Ledger) WouldBePermanent(
netblock netip.Prefix, now time.Time, cause string,
) bool {
@@ -331,11 +363,14 @@ func (l *Ledger) WouldBePermanent(
held = *bans
}
if cause == CauseAttack {
switch cause {
case CauseAttack:
return l.attackExpiry(held, now).IsZero()
case CauseLimit:
return l.limitExpiry(held, now).IsZero()
default: // CauseCrowdSec
return false
}
return l.limitExpiry(held, now).IsZero()
}
// limitReason is the reason of a ban for a broken limit, with notes.
@@ -350,6 +385,12 @@ func attackReason(notes Notes) string {
return "matched the rule " + notes.RuleID
}
// crowdSecReason is the reason of a ban for CrowdSec's decision, which
// scenario made.
func crowdSecReason(scenario string) string {
return "CrowdSec's decision for " + scenario
}
// BanForAdmin bans netblock at now for an admin, with reason, until
// expires, or for good when expires is zero, and returns the ban, whose
// cause is CauseAdmin. Unlike BanForLimit and BanForAttack, it makes the
@@ -587,11 +628,14 @@ func (l *Ledger) holds(netblock netip.Prefix, start time.Time) bool {
}
// ban bans netblock at now for cause, with reason and notes, as
// BanForLimit and BanForAttack describe, and returns the ban, and whether
// it made it. Unless keep is true, the ban is not made, only returned: it
// is the ban that would have been made.
// BanForLimit, BanForAttack and BanForCrowdSec describe, and returns the
// ban, and whether it made it. expires is when a ban for CauseCrowdSec
// ends, and zero for the others, whose end the ledger works out. Unless
// keep is true, the ban is not made, only returned: it is the ban that
// would have been made.
func (l *Ledger) ban(
netblock netip.Prefix, now time.Time, cause, reason string, notes Notes, keep bool,
netblock netip.Prefix, now, expires time.Time, cause, reason string, notes Notes,
keep bool,
) (Ban, bool) {
l.mu.Lock()
defer l.mu.Unlock()
@@ -613,10 +657,13 @@ func (l *Ledger) ban(
notes.Request = notes.Request.cut()
ban := Ban{Netblock: netblock, Start: now, Cause: cause, Reason: reason, Notes: notes}
if cause == CauseAttack {
switch cause {
case CauseAttack:
ban.Expires = l.attackExpiry(held, now)
} else {
case CauseLimit:
ban.Expires = l.limitExpiry(held, now)
default: // CauseCrowdSec
ban.Expires = expires
}
if !keep {
@@ -645,6 +692,8 @@ func earlierBans(held []Ban) EarlierBans {
earlier.Attack++
case CauseAdmin:
earlier.Admin++
case CauseCrowdSec:
earlier.CrowdSec++
}
}
@@ -738,16 +787,16 @@ func (l *Ledger) add(ban Ban) {
// limitExpiry returns when a ban for a broken limit made at now ends, or
// zero when it is permanent. held are the netblock's bans, none of them
// active, of which the one that ended last, other than a ban for a clear
// sign of attack or a lifted one, can make the new ban longer. A ban an
// admin adds to bans.json can start after another and end before it, so
// that one is looked for among them all.
// sign of attack or for CrowdSec's decision, or a lifted one, can make the
// new ban longer. A ban an admin adds to bans.json can start after
// another and end before it, so that one is looked for among them all.
func (l *Ledger) limitExpiry(held []Ban, now time.Time) time.Time {
length := l.rules.LimitBanDuration
var last *Ban
for i, ban := range held {
if ban.Cause != CauseAttack && ban.Lifted.IsZero() &&
if (ban.Cause == CauseLimit || ban.Cause == CauseAdmin) && ban.Lifted.IsZero() &&
(last == nil || ban.Expires.After(last.Expires)) {
last = &held[i]
}
internal/bans/crowdsec_test.go
+90
View File
@@ -0,0 +1,90 @@
package bans_test
import (
"net/netip"
"reflect"
"testing"
"time"
"sneak.berlin/go/smallwebwaf/internal/bans"
)
// scenario is the scenario of the tests' CrowdSec decisions.
const scenario = "crowdsecurity/ssh-bf"
func TestCrowdSecBanLastsUntilTheDecisionEnds(t *testing.T) {
t.Parallel()
ledger := bans.New(defaultRules())
netblock := netip.MustParsePrefix("203.0.113.9/32")
expires := midnight().Add(4 * time.Hour)
// The ban that would be made is not made.
would, wouldBan := ledger.WouldBanForCrowdSec(netblock, midnight(), expires,
scenario, bans.Notes{})
if !wouldBan || len(ledger.Bans(netblock)) != 0 {
t.Errorf("would ban %t, and the ledger holds %+v, want true and nothing",
wouldBan, ledger.Bans(netblock))
}
const reason = "CrowdSec's decision for " + scenario
ban, made := ledger.BanForCrowdSec(netblock, midnight(), expires, scenario,
bans.Notes{})
if !made || !reflect.DeepEqual(ban, would) || ban.Cause != bans.CauseCrowdSec ||
!ban.Expires.Equal(expires) || ban.Reason != reason ||
ledger.Made(bans.CauseCrowdSec) != 1 {
t.Errorf("made %t the ban %+v, want the one that would be made, %+v, for "+
"crowdsec until %s", made, ban, would, expires)
}
// A second decision on the netblock while the ban lasts makes no other.
again, made := ledger.BanForCrowdSec(netblock, midnight().Add(time.Hour),
expires.Add(time.Hour), scenario, bans.Notes{})
if made || !again.Expires.Equal(expires) || ledger.Made(bans.CauseCrowdSec) != 1 {
t.Errorf("made %t the ban %+v while the first lasts, want none", made, again)
}
}
func TestCrowdSecBanIsNeverMadePermanent(t *testing.T) {
t.Parallel()
ledger := bans.New(defaultRules())
netblock := netip.MustParsePrefix("203.0.113.9/32")
expires := midnight().Add(4 * time.Hour)
ledger.BanForCrowdSec(netblock, midnight(), expires, scenario, bans.Notes{})
// A request as the ban ends is refused, and leaves it as it is.
last := expires.Add(-time.Nanosecond)
held, banned, madePermanent := ledger.Check(netblock.Addr(), last)
if !banned || madePermanent || !held.Expires.Equal(expires) ||
ledger.WouldBePermanent(netblock, last, bans.CauseCrowdSec) {
t.Errorf("as the ban ends, banned %t with %+v, made permanent %t, want "+
"refused under the ban as it was", banned, held, madePermanent)
}
if _, banned, _ := ledger.Check(netblock.Addr(), expires); banned {
t.Error("the ban refuses a request once the decision has ended")
}
}
func TestCrowdSecBanIsCountedAndDoesNotLengthenTheNextBanForALimit(t *testing.T) {
t.Parallel()
ledger := bans.New(defaultRules())
netblock := netip.MustParsePrefix("203.0.113.9/32")
// Three times the three days would be permanent; a limit broken as the
// ban for CrowdSec's decision ends bans for an hour, as a first broken
// limit does.
crowdSec, _ := ledger.BanForCrowdSec(netblock, midnight(), midnight().Add(3*day),
scenario, bans.Notes{})
limit, _ := ledger.BanForLimit(netblock, crowdSec.Expires, bans.Notes{})
if limit.Expires.Sub(limit.Start) != time.Hour ||
limit.Notes.EarlierBans != (bans.EarlierBans{CrowdSec: 1}) {
t.Errorf("the ban for a limit is %+v, want one of an hour after one for crowdsec",
limit)
}
}
internal/config/config.go
+57
View File
@@ -181,6 +181,13 @@ type Config struct {
ReputationLimitPercent int64
ReputationCacheTTL time.Duration
ReputationTimeout time.Duration
// CrowdSecDecisionsURL is where the decision list of the CrowdSec
// engine whose local API SWWAF_CROWDSEC_LAPI_URL names is fetched from:
// that URL with v1/decisions added to its path, "" while it is unset and
// none is. CrowdSecKey is the key the engine is asked with
// (SWWAF_CROWDSEC_LAPI_KEY).
CrowdSecDecisionsURL string
CrowdSecKey string
// BanResponse is the status a refused client is answered with, 403
// or 429, or 0 to close the connection without an answer
// (SWWAF_BAN_RESPONSE). It answers a banned client, a request that
@@ -410,6 +417,13 @@ var (
"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(
"is not an http or https URL without a user or a fragment, " +
"such as http://172.17.0.1:8080")
errNeedsLAPIKey = errors.New("the engine answers no request without it")
errLAPIKeyUnused = errors.New("it is sent only to the engine at that URL")
errAnotherList = errors.New(
"is in SWWAF_BLOCKLIST_URLS or is SWWAF_ASN_LIMIT_PERCENT_URL too")
)
// FromEnvironment reads the settings with lookupEnv, normally
@@ -471,6 +485,8 @@ func FromEnvironment(lookupEnv func(string) (string, bool)) (*Config, error) {
AbuseIPDBDailyBudget: env.numberNotOff("SWWAF_ABUSEIPDB_DAILY_BUDGET", "900"),
ReputationCacheTTL: env.durationNotOff("SWWAF_REPUTATION_CACHE_TTL", "24h"),
ReputationTimeout: env.durationNotOff("SWWAF_REPUTATION_TIMEOUT", "2s"),
CrowdSecDecisionsURL: env.crowdSecDecisionsURL("SWWAF_CROWDSEC_LAPI_URL"),
CrowdSecKey: env.secret("SWWAF_CROWDSEC_LAPI_KEY"),
BanResponse: env.banResponse("SWWAF_BAN_RESPONSE", "403"),
LimitBanDuration: env.durationNotOff("SWWAF_LIMIT_BAN_DURATION", "1h"),
LimitBanRepeatWindow: env.durationNotOff("SWWAF_LIMIT_BAN_REPEAT_WINDOW", "24h"),
@@ -523,6 +539,7 @@ func FromEnvironment(lookupEnv func(string) (string, bool)) (*Config, error) {
env.checkLookupDBPath(cfg)
env.checkCountriesAndLookups(cfg)
env.checkASNLimitPercentURL(cfg)
env.checkCrowdSec(cfg)
if env.err != nil {
return nil, env.err
@@ -835,6 +852,26 @@ func (e *environment) resolver(name string) netip.AddrPort {
return resolver
}
// crowdSecDecisionsURL reads the setting that is the URL of the CrowdSec
// engine's local API, such as http://172.17.0.1:8080, and returns the URL
// its decision list is fetched from, that URL with v1/decisions added to
// its path, "" while it is unset or empty.
func (e *environment) crowdSecDecisionsURL(name string) string {
value := e.value(name, "")
if value == "" {
return ""
}
lapi, err := url.Parse(value)
if err != nil || !isHTTPURL(lapi) {
e.check(name, fmt.Errorf("%q %w", value, errNotLAPIURL))
return ""
}
return lapi.JoinPath("v1", "decisions").String()
}
// lookupSource reads the setting that is where clients are looked up:
// geojs, file, or off.
func (e *environment) lookupSource(name, defaultValue string) string {
@@ -912,6 +949,26 @@ func (e *environment) checkASNLimitPercentURL(cfg *Config) {
}
}
// checkCrowdSec refuses SWWAF_CROWDSEC_LAPI_URL without
// SWWAF_CROWDSEC_LAPI_KEY, the key without the URL, and a decision list
// that is fetched as another list too.
func (e *environment) checkCrowdSec(cfg *Config) {
decisionsURL := cfg.CrowdSecDecisionsURL
switch {
case decisionsURL != "" && cfg.CrowdSecKey == "":
e.check("SWWAF_CROWDSEC_LAPI_URL", fmt.Errorf(
"is set while SWWAF_CROWDSEC_LAPI_KEY is unset; %w", errNeedsLAPIKey))
case decisionsURL == "" && cfg.CrowdSecKey != "":
e.check("SWWAF_CROWDSEC_LAPI_KEY", fmt.Errorf(
"is set while SWWAF_CROWDSEC_LAPI_URL is unset; %w", errLAPIKeyUnused))
case decisionsURL != "" && (slices.Contains(cfg.BlocklistURLs, decisionsURL) ||
decisionsURL == cfg.ASNLimitPercentURL):
e.check("SWWAF_CROWDSEC_LAPI_URL", fmt.Errorf("gives the decision list %q, which %w",
decisionsURL, errAnotherList))
}
}
// headerNames reads a setting that is a list of header names, and
// returns them in lower case.
func (e *environment) headerNames(name, defaultValue string) []string {
internal/config/config_test.go
+119
View File
@@ -71,6 +71,8 @@ const (
reputationAction = "SWWAF_REPUTATION_ACTION"
reputationCacheTTL = "SWWAF_REPUTATION_CACHE_TTL"
reputationTimeout = "SWWAF_REPUTATION_TIMEOUT"
crowdSecURL = "SWWAF_CROWDSEC_LAPI_URL"
crowdSecKey = "SWWAF_CROWDSEC_LAPI_KEY"
banResponse = "SWWAF_BAN_RESPONSE"
limitBanDuration = "SWWAF_LIMIT_BAN_DURATION"
limitBanRepeatWindow = "SWWAF_LIMIT_BAN_REPEAT_WINDOW"
@@ -1653,6 +1655,121 @@ func TestAbuseIPDBKeyIsLoggedMasked(t *testing.T) {
}
}
func TestCrowdSecSettingsGiveTheDecisionListAndTheKey(t *testing.T) {
t.Parallel()
cfg := fromEnvironment(t, environment{})
if cfg.CrowdSecDecisionsURL != "" || cfg.CrowdSecKey != "" {
t.Errorf("by default, the decision list %q and the key %q, want neither",
cfg.CrowdSecDecisionsURL, cfg.CrowdSecKey)
}
for lapi, want := range map[string]string{
"http://172.17.0.1:8080": "http://172.17.0.1:8080/v1/decisions",
"http://172.17.0.1:8080/": "http://172.17.0.1:8080/v1/decisions",
"https://crowdsec.example/lapi/": "https://crowdsec.example/lapi/v1/decisions",
"https://crowdsec.example:8443/x": "https://crowdsec.example:8443/x/v1/decisions",
} {
cfg := fromEnvironment(t, environment{crowdSecURL: lapi, crowdSecKey: token})
if cfg.CrowdSecDecisionsURL != want || cfg.CrowdSecKey != token {
t.Errorf("%s=%s gave the decision list %q and the key %q, want %s and %s",
crowdSecURL, lapi, cfg.CrowdSecDecisionsURL, cfg.CrowdSecKey, want, token)
}
}
}
func TestInvalidCrowdSecSettingStopsTheStartSayingWhatIsWrong(t *testing.T) {
t.Parallel()
const (
lapi = "http://172.17.0.1:8080"
notLAPIURL = " is not an http or https URL without a user or a fragment, " +
"such as http://172.17.0.1:8080"
anotherList = `gives the decision list "` + lapi + `/v1/decisions", which is in ` +
`SWWAF_BLOCKLIST_URLS or is SWWAF_ASN_LIMIT_PERCENT_URL too`
)
for _, tc := range []struct {
name string
env environment
want string
}{
{
"a URL that is not http",
environment{crowdSecURL: "ftp://172.17.0.1", crowdSecKey: token},
crowdSecURL + `: "ftp://172.17.0.1"` + notLAPIURL,
},
{
"a URL with a user",
environment{crowdSecURL: "http://bouncer@172.17.0.1:8080", crowdSecKey: token},
crowdSecURL + `: "http://bouncer@172.17.0.1:8080"` + notLAPIURL,
},
{
"the URL without the key",
environment{crowdSecURL: lapi},
crowdSecURL + ": is set while " + crowdSecKey + " is unset; the engine " +
"answers no request without it",
},
{
"the key without the URL",
environment{crowdSecKey: token},
crowdSecKey + ": is set while " + crowdSecURL + " is unset; it is sent only " +
"to the engine at that URL",
},
{
"the decision list as a blocklist too",
environment{
crowdSecURL: lapi, crowdSecKey: token,
blocklistURLs: "https://lists.example/drop.txt," + lapi + "/v1/decisions",
},
crowdSecURL + ": " + anotherList,
},
{
"the decision list as the file of AS:percent lines too",
environment{
crowdSecURL: lapi + "/", crowdSecKey: token,
asnLimitPercentURL: lapi + "/v1/decisions",
},
crowdSecURL + ": " + anotherList,
},
// The key itself is never shown.
{
"a key with a control character",
environment{crowdSecURL: lapi, crowdSecKey: token + "\r"},
crowdSecKey + ": holds a control character, such as the carriage return " +
"of a Windows line end",
},
} {
t.Run(tc.name, func(t *testing.T) {
t.Parallel()
_, err := config.FromEnvironment(tc.env.lookupEnv)
if err == nil || err.Error() != tc.want {
t.Errorf("error %v, want %s", err, tc.want)
}
})
}
}
func TestCrowdSecKeyIsLoggedMasked(t *testing.T) {
t.Parallel()
cfg := fromEnvironment(t, environment{
crowdSecURL: "http://172.17.0.1:8080", crowdSecKey: token,
})
var out bytes.Buffer
slog.New(slog.NewJSONHandler(&out, nil)).Info("starting", "settings", cfg)
logged := out.String()
if strings.Contains(logged, token) ||
!strings.Contains(logged, `"`+crowdSecKey+`":"********"`) ||
!strings.Contains(logged, `"`+crowdSecURL+`":"http://172.17.0.1:8080"`) {
t.Errorf("the key is not logged masked beside the URL: %s", logged)
}
}
func TestSizesAndOff(t *testing.T) {
t.Parallel()
@@ -2096,6 +2213,8 @@ func TestLogsEachSettingWithItsValue(t *testing.T) {
reputationAction: "limit:25",
reputationCacheTTL: defaultReputationCacheTTL,
reputationTimeout: "2s",
crowdSecURL: "",
crowdSecKey: "",
banResponse: "403",
limitBanDuration: "1h",
limitBanRepeatWindow: "24h",
internal/metrics/metrics.go
+14 -11
View File
@@ -154,7 +154,9 @@ func New(topN int, instanceName string) *Metrics {
func (m *Metrics) AddBansAndClients(
ledger *bans.Ledger, limiter *ratelimit.Limiter, now func() time.Time,
) {
for _, cause := range []string{bans.CauseLimit, bans.CauseAttack, bans.CauseAdmin} {
for _, cause := range []string{
bans.CauseLimit, bans.CauseAttack, bans.CauseAdmin, bans.CauseCrowdSec,
} {
m.registry.MustRegister(prometheus.NewCounterFunc(prometheus.CounterOpts{
Name: "smallwebwaf_bans_made_total",
Help: "Bans made, by cause.",
@@ -263,16 +265,16 @@ const sourceLabel = "source"
// AddReputation adds the metrics of the lists fetched from URLs and of the
// DNSBL zones, by source, each list's URL or each zone, its key masked as
// config.MaskZoneKey masks it: the requests whose client a blocklist, a
// zone's verdict or AbuseIPDB's score lists, which ReputationHit counts,
// and, read from lists and dnsbl as the metrics are asked for, for a list,
// the fetches that failed and when the copy in use was fetched, and for a
// zone, the queries made and those that failed. It is called once, before
// ReputationHit.
// config.MaskZoneKey masks it: the requests whose client a blocklist, the
// CrowdSec decision list, a zone's verdict or AbuseIPDB's score lists,
// which ReputationHit counts, and, read from lists and dnsbl as the
// metrics are asked for, for a list, the fetches that failed and when the
// copy in use was fetched, and for a zone, the queries made and those that
// failed. It is called once, before ReputationHit.
func (m *Metrics) AddReputation(lists *reputation.Lists, dnsbl *reputation.DNSBL) {
m.reputationHits = counterVec("smallwebwaf_reputation_hits_total",
"Requests whose client a blocklist, a DNSBL zone or AbuseIPDB lists, by "+
"the blocklist's URL, the zone, or abuseipdb.",
"Requests whose client a blocklist, the CrowdSec decision list, a DNSBL "+
"zone or AbuseIPDB lists, by the list's URL, the zone, or abuseipdb.",
[]string{sourceLabel})
m.registry.MustRegister(m.reputationHits)
@@ -325,8 +327,9 @@ func (m *Metrics) AddAbuseIPDB(abuseIPDB *reputation.AbuseIPDB) {
)
}
// ReputationHit counts a request whose client source lists: a blocklist,
// by its URL, a DNSBL zone, its key masked, or AbuseIPDB, abuseipdb.
// ReputationHit counts a request whose client source lists: a blocklist
// or the CrowdSec decision list, by its URL, a DNSBL zone, its key masked,
// or AbuseIPDB, abuseipdb.
func (m *Metrics) ReputationHit(source string) {
m.reputationHits.WithLabelValues(source).Inc()
}
internal/proxy/bans.go
+39
View File
@@ -7,6 +7,7 @@ import (
"sneak.berlin/go/smallwebwaf/internal/alerts"
"sneak.berlin/go/smallwebwaf/internal/bans"
"sneak.berlin/go/smallwebwaf/internal/ratelimit"
"sneak.berlin/go/smallwebwaf/internal/reputation"
"sneak.berlin/go/smallwebwaf/internal/requestlog"
"sneak.berlin/go/smallwebwaf/internal/rules"
)
@@ -202,6 +203,44 @@ func (rq *request) banForAttack(now time.Time, rule rules.Rule) {
}
}
// banForCrowdSec bans the client's netblock at now until decision,
// CrowdSec's decision on the client, ends. In observe mode it makes no
// ban, and raises the alert for the ban it would have made, if that alert
// would be sent.
func (rq *request) banForCrowdSec(now time.Time, decision reputation.Decision) {
netblock := rq.h.netblock(rq.client)
if rq.h.config.Observe && !rq.wouldAlertBan(netblock, now, bans.CauseCrowdSec) {
return
}
notes := bans.Notes{
ASN: rq.line.ASN,
ASName: rq.line.ASName,
Country: rq.line.Country,
Reputation: rq.reputation,
Request: rq.noted(now, rq.h.config.BanResponse),
Requests: rq.netblockRequests(netblock),
}
if rq.h.config.Observe {
ban, wouldBan := rq.h.ledger.WouldBanForCrowdSec(netblock, now, decision.Expires,
decision.Scenario, notes)
if wouldBan {
rq.alertBan(ban)
}
return
}
ban, made := rq.h.ledger.BanForCrowdSec(netblock, now, decision.Expires,
decision.Scenario, notes)
rq.line.BanExpires = banExpires(ban)
if made {
rq.alertBan(ban)
}
}
// wouldAlertBan reports whether the alert for a ban on netblock for cause
// made at now would be sent. In observe mode the ban the request would
// have made is worked out only then, at most once per
internal/proxy/crowdsec_test.go
+181
View File
@@ -0,0 +1,181 @@
package proxy_test
import (
"net/http"
"net/netip"
"reflect"
"testing"
"time"
"sneak.berlin/go/smallwebwaf/internal/alerts"
"sneak.berlin/go/smallwebwaf/internal/bans"
"sneak.berlin/go/smallwebwaf/internal/proxy"
"sneak.berlin/go/smallwebwaf/internal/reputation"
"sneak.berlin/go/smallwebwaf/internal/requestlog"
)
// The CrowdSec settings, and the tests' engine, which is never asked: each
// test puts in the copy of its decision list, at decisionsURL, that it
// needs, as reputation.json would at start.
const (
crowdSecURL = "SWWAF_CROWDSEC_LAPI_URL"
crowdSecKey = "SWWAF_CROWDSEC_LAPI_KEY"
lapi = "http://crowdsec.example:8080"
decisionsURL = lapi + "/v1/decisions"
bouncerKey = "crowdsec-key-0123456789abcdef"
)
func TestClientTheCrowdSecDecisionListListsIsBannedUntilTheDecisionEnds(t *testing.T) {
t.Parallel()
s, clk, server, queue := startWithAlerts(t, map[string]string{
crowdSecURL: lapi, crowdSecKey: bouncerKey, metricsToken: token,
})
// client had four hours left on its decision as the engine answered.
fetched := clk.Now()
loadDecisions(t, server, fetched, `[{"duration": "4h0m0s", `+
`"scenario": "crowdsecurity/ssh-bf", "scope": "Ip", "type": "ban", `+
`"value": "`+client+`"}]`)
expires := requestlog.FormatTime(fetched.Add(4 * time.Hour))
// Its first request is refused, and bans it until the decision ends.
line := s.get(client, http.StatusForbidden, requestlog.ActionBanned)
wantReputation(t, line, decisionsURL)
if line.BanExpires != expires {
t.Errorf("log line has ban_expires %q, want %s", line.BanExpires, expires)
}
listed := []bans.ReputationHit{{Source: decisionsURL}}
held := server.Ledger.Bans(netip.MustParsePrefix(client + "/32"))
if len(held) != 1 || held[0].Cause != bans.CauseCrowdSec ||
!held[0].Start.Equal(fetched) || !held[0].Expires.Equal(fetched.Add(4*time.Hour)) ||
held[0].Reason != "CrowdSec's decision for crowdsecurity/ssh-bf" ||
!reflect.DeepEqual(held[0].Notes.Reputation, listed) ||
held[0].Notes.Request.Path != "/" || held[0].Notes.Requests != 1 {
t.Fatalf("bans %+v, want one for crowdsec of four hours, with the list and "+
"the request in its notes", held)
}
// The listing raises a reputation_hit alert, and the ban its own.
waiting := queue.Snapshot().Waiting[alerts.DestinationWebhook]
if len(waiting) != 2 || waiting[0].Event != alerts.EventReputationHit ||
waiting[0].Reason != "listed by the CrowdSec decision list" ||
!reflect.DeepEqual(waiting[1], banAlert(alerts.EventBan, fetched, client, held[0],
expires)) {
t.Errorf("alerts waiting %+v, want a reputation_hit alert, then the ban's",
waiting)
}
// Each request while the ban lasts is refused under it, as under any
// ban, and once it has ended the client is let through.
clk.advance(4*time.Hour - time.Second)
line = s.get(client, http.StatusForbidden, requestlog.ActionBanned)
wantReputation(t, line)
if line.BanExpires != expires {
t.Errorf("log line has ban_expires %q, want %s", line.BanExpires, expires)
}
clk.advance(time.Second)
s.get(client, http.StatusOK, requestlog.ActionForward)
// The ban and the hit are counted, and the list has the metrics of any
// list fetched from a URL.
metrics := s.scrape(unplaced)
labels := `{instance="` + alertInstance + `",source="` + decisionsURL + `"}`
wantMetric(t, metrics, `smallwebwaf_bans_made_total{cause="crowdsec",`+
`instance="`+alertInstance+`"}`, 1)
wantMetric(t, metrics, "smallwebwaf_reputation_hits_total"+labels, 1)
wantMetric(t, metrics, "smallwebwaf_reputation_failures_total"+labels, 0)
wantMetric(t, metrics, "smallwebwaf_reputation_last_fetch_timestamp_seconds"+labels,
float64(fetched.Unix()))
}
func TestEndedCrowdSecDecisionNoLongerBansThoughTheCopyStillHoldsIt(t *testing.T) {
t.Parallel()
s, clk, server := startWithClock(t, "", map[string]string{
crowdSecURL: lapi, crowdSecKey: bouncerKey,
})
// 198.51.100.0/24 and 2001:db8::9 had a minute left as the engine
// answered.
fetched := clk.Now()
loadDecisions(t, server, fetched, `[{"duration": "1m0s", `+
`"scenario": "crowdsecurity/http-probing", "scope": "Range", "type": "ban", `+
`"value": "198.51.100.0/24"}, {"duration": "1m0s", `+
`"scenario": "crowdsecurity/http-probing", "scope": "Ip", "type": "ban", `+
`"value": "2001:db8::9"}]`)
// Just before its end, the decision bans a client in the netblock, and
// one on an IPv6 address bans the address's group, the /64.
clk.advance(time.Minute - time.Nanosecond)
s.get("198.51.100.7", http.StatusForbidden, requestlog.ActionBanned)
s.get("2001:db8::9", http.StatusForbidden, requestlog.ActionBanned)
s.get("2001:db8::5", http.StatusForbidden, requestlog.ActionBanned)
// Once it has ended, it bans no other client, and the bans it made end
// with it.
clk.advance(time.Nanosecond)
for _, from := range []string{"198.51.100.8", "198.51.100.7", "2001:db8::5"} {
wantReputation(t, s.get(from, http.StatusOK, requestlog.ActionForward))
}
if made := server.Ledger.Made(bans.CauseCrowdSec); made != 2 {
t.Errorf("%d bans made for crowdsec, want 2, on 198.51.100.7/32 and "+
"2001:db8::/64", made)
}
if held := server.Ledger.Bans(netip.MustParsePrefix("2001:db8::/64")); len(held) != 1 {
t.Errorf("bans of 2001:db8::/64 %+v, want one", held)
}
}
func TestObserveModeForwardsAClientTheCrowdSecDecisionListListsAndAlertsTheBan(
t *testing.T,
) {
t.Parallel()
s, clk, server, queue := startWithAlerts(t, map[string]string{
crowdSecURL: lapi, crowdSecKey: bouncerKey, mode: observe,
})
loadDecisions(t, server, clk.Now(), `[{"duration": "4h0m0s", `+
`"scenario": "crowdsecurity/ssh-bf", "scope": "Ip", "type": "ban", `+
`"value": "`+client+`"}]`)
line := s.get(client, http.StatusOK, requestlog.ActionForward)
wantWouldAction(t, line, requestlog.ActionBanned)
wantReputation(t, line, decisionsURL)
if held := server.Ledger.Snapshot(); len(held) != 0 {
t.Errorf("bans %+v, want none", held)
}
waiting := queue.Snapshot().Waiting[alerts.DestinationWebhook]
if len(waiting) != 2 || waiting[1].Event != alerts.EventBan ||
waiting[1].Detail["cause"] != bans.CauseCrowdSec ||
waiting[1].Detail["mode"] != observe {
t.Errorf("alerts waiting %+v, want a reputation_hit alert, then the ban alert "+
"marked observe", waiting)
}
}
// loadDecisions puts into server's lists the copy of the decision list at
// decisionsURL, answer, the engine's answer, fetched at fetched, as
// reputation.json would at start.
func loadDecisions(
t *testing.T, server *proxy.Server, fetched time.Time, answer string,
) {
t.Helper()
err := server.Lists.Load([]reputation.List{{
URL: decisionsURL, Tried: fetched, Fetched: fetched, Lines: []string{answer},
}})
if err != nil {
t.Fatalf("load the decision list: %v", err)
}
}
internal/proxy/proxy.go
+7 -5
View File
@@ -74,9 +74,10 @@ type Params struct {
Rules *rules.Files
// Alerts receive the alert for each ban the proxy makes or makes
// permanent, for each count over an anomaly threshold, for each request
// whose client a blocklist, a DNSBL zone or AbuseIPDB lists, and for
// GeoJS failing, a fetch of a list failing, a query to a DNSBL zone or
// a check with AbuseIPDB failing, or the day's AbuseIPDB checks used up.
// whose client a blocklist, the CrowdSec decision list, a DNSBL zone or
// AbuseIPDB lists, and for GeoJS failing, a fetch of a list failing, a
// query to a DNSBL zone or a check with AbuseIPDB failing, or the day's
// AbuseIPDB checks used up.
Alerts *alerts.Queue
}
@@ -202,8 +203,9 @@ func newReputation(
cfg := params.Config
lists := reputation.New(reputation.Params{
BlocklistURLs: cfg.BlocklistURLs, Refresh: cfg.BlocklistRefresh,
ASNLimitPercentURL: cfg.ASNLimitPercentURL, Now: params.Now,
ProcessLog: params.ProcessLog, Alerts: params.Alerts,
ASNLimitPercentURL: cfg.ASNLimitPercentURL,
CrowdSecDecisionsURL: cfg.CrowdSecDecisionsURL, CrowdSecKey: cfg.CrowdSecKey,
Now: params.Now, ProcessLog: params.ProcessLog, Alerts: params.Alerts,
})
dnsbl := reputation.NewDNSBL(reputation.DNSBLParams{
Zones: cfg.DNSBLZones, Resolver: cfg.DNSBLResolver, CacheTTL: cfg.ReputationCacheTTL,
internal/proxy/reputation.go
+17
View File
@@ -2,6 +2,7 @@ package proxy
import (
"context"
"time"
"sneak.berlin/go/smallwebwaf/internal/alerts"
"sneak.berlin/go/smallwebwaf/internal/bans"
@@ -25,6 +26,22 @@ func (rq *request) blocklistDenied() bool {
return rq.blocklisted && rq.h.config.BlocklistAction == deny
}
// crowdSecBanned reports whether a decision of the CrowdSec decision list
// on the client is in force at now. If one is, it notes the list, as
// noteHit does, and bans the client until that decision ends.
func (rq *request) crowdSecBanned(now time.Time) bool {
decision, listed := rq.h.lists.CrowdSecDecision(rq.client, now)
if !listed {
return false
}
rq.noteHit(bans.ReputationHit{Source: rq.h.config.CrowdSecDecisionsURL},
"listed by the CrowdSec decision list")
rq.banForCrowdSec(now, decision)
return true
}
// dnsblDenied notes the DNSBL zones whose verdict lists the client, as
// noteListed does, and reports whether SWWAF_REPUTATION_ACTION, being
// deny, refuses the request. Being limit, it lowers the client's limits
internal/proxy/request.go
+7 -2
View File
@@ -226,8 +226,9 @@ func (rq *request) check(ctx context.Context) *refusal {
// other client, SWWAF_DENY_NETS comes first, then a ban on its netblock,
// so that a client either refuses is not looked up, then the lookup of
// its AS number and country, then the country lists, then the blocklists,
// then the DNSBL zones' verdicts, and then AbuseIPDB's score; a request
// any of them refuses is not counted for the rate limits. Then come the
// then the CrowdSec decision list, which bans the client it lists, then
// the DNSBL zones' verdicts, and then AbuseIPDB's score; a request any of
// them refuses is not counted for the rate limits. Then come the
// rate limits, unless the client is in SWWAF_RATE_LIMIT_EXEMPT_NETS or the
// request's path is exempt under SWWAF_RATE_LIMIT_EXEMPT_PATHS, so that
// every other request is counted, each of them by the client's limit
@@ -260,6 +261,10 @@ func (rq *request) checkClient(ctx context.Context) string {
return requestlog.ActionDenied
}
if rq.crowdSecBanned(now) {
return requestlog.ActionBanned
}
if rq.dnsblDenied(ctx) || rq.abuseIPDBDenied(ctx) {
return requestlog.ActionDenied
}
internal/reputation/crowdsec_test.go
+513
View File
@@ -0,0 +1,513 @@
package reputation_test
import (
"bytes"
"encoding/json"
"fmt"
"io"
"log/slog"
"net/http"
"net/netip"
"reflect"
"strings"
"sync"
"testing"
"testing/synctest"
"time"
"sneak.berlin/go/smallwebwaf/internal/alerts"
"sneak.berlin/go/smallwebwaf/internal/reputation"
)
// The tests run in a synctest bubble, as those of the blocklists do, and
// fetch the decision list from engine, a stand-in for a CrowdSec engine
// that answers without the network.
const (
// decisionsURL is the decision list of the tests' engine, and engineKey
// the key it answers.
decisionsURL = "http://crowdsec.example:8080/v1/decisions"
engineKey = "crowdsec-key-0123456789abcdef"
// sshBF and probing are scenarios of the engine's decisions.
sshBF = "crowdsecurity/ssh-bf"
probing = "crowdsecurity/http-probing"
// ban is the type of a decision to ban, and rangeScope the scope of a
// decision on a netblock, as CrowdSec names them.
ban = "ban"
rangeScope = "Range"
)
func TestCrowdSecDecisionBansItsNetblockUntilItEndsEvenWithTheEngineDown(t *testing.T) {
t.Parallel()
synctest.Test(t, func(t *testing.T) {
began := time.Now()
manual := "manual 'ban' from 'localhost'"
e := &engine{key: engineKey, decisions: []decision{
{"Ip", suspect, ban, manual, began.Add(6 * time.Hour)},
// A shorter decision on the same address, which is not the one
// used.
{"Ip", suspect, ban, sshBF, began.Add(4 * time.Hour)},
{rangeScope, "198.51.100.0/24", ban, probing, began.Add(time.Hour)},
{"Ip", "2001:db8::1", ban, sshBF, began.Add(2 * time.Hour)},
// Left out: a decision to show a captcha, and one on a country.
{"Ip", "192.0.2.50", "captcha", probing, began.Add(time.Hour)},
{"Country", "KP", ban, manual, began.Add(time.Hour)},
}}
lists := start(t, e, crowdSecParams())
for addr, want := range map[string]reputation.Decision{
suspect: {Expires: began.Add(6 * time.Hour), Scenario: manual},
"198.51.100.0": {Expires: began.Add(time.Hour), Scenario: probing},
"198.51.100.255": {Expires: began.Add(time.Hour), Scenario: probing},
"2001:db8::1": {Expires: began.Add(2 * time.Hour), Scenario: sshBF},
"203.0.113.10": {},
"198.51.101.0": {},
"2001:db8::2": {},
"192.0.2.50": {},
} {
wantDecision(t, lists, addr, want)
}
// With the engine down, the copy kept still holds the decision on
// 198.51.100.0/24, which no longer bans once it has ended.
e.set(func(e *engine) { e.failing = true })
time.Sleep(time.Hour - time.Nanosecond)
synctest.Wait()
wantDecision(t, lists, "198.51.100.7",
reputation.Decision{Expires: began.Add(time.Hour), Scenario: probing})
time.Sleep(time.Nanosecond)
synctest.Wait()
wantDecision(t, lists, "198.51.100.7", reputation.Decision{})
wantDecision(t, lists, suspect,
reputation.Decision{Expires: began.Add(6 * time.Hour), Scenario: manual})
})
}
func TestCrowdSecDecisionListFetchedAgainEveryMinute(t *testing.T) {
t.Parallel()
synctest.Test(t, func(t *testing.T) {
began := time.Now()
e := &engine{key: engineKey, decisions: []decision{
{"Ip", suspect, ban, sshBF, began.Add(4 * time.Hour)},
}}
lists := start(t, e, crowdSecParams())
wantEngineFetches(t, e, 1)
added := reputation.Decision{Expires: began.Add(2 * time.Hour), Scenario: probing}
e.set(func(e *engine) {
e.decisions = append(e.decisions,
decision{"Ip", "203.0.113.10", ban, probing, added.Expires})
})
time.Sleep(time.Minute - time.Nanosecond)
wantEngineFetches(t, e, 1)
wantDecision(t, lists, "203.0.113.10", reputation.Decision{})
time.Sleep(time.Nanosecond)
wantEngineFetches(t, e, 2)
wantDecision(t, lists, "203.0.113.10", added)
})
}
func TestCrowdSecDecisionOnAClientIsTheOneThatEndsLast(t *testing.T) {
t.Parallel()
synctest.Test(t, func(t *testing.T) {
began := time.Now()
e := &engine{key: engineKey, decisions: []decision{
// Two decisions on one address, the shorter listed first.
{"Ip", suspect, ban, sshBF, began.Add(2 * time.Hour)},
{"Ip", suspect, ban, probing, began.Add(4 * time.Hour)},
// 198.51.100.130 is held by a decision on its address that ends
// after the one on its netblock, and 192.0.2.20 by one that ends
// before.
{rangeScope, "198.51.100.128/25", ban, sshBF, began.Add(time.Hour)},
{"Ip", "198.51.100.130", ban, probing, began.Add(3 * time.Hour)},
{rangeScope, "192.0.2.0/24", ban, probing, began.Add(5 * time.Hour)},
{"Ip", "192.0.2.20", ban, sshBF, began.Add(2 * time.Hour)},
}}
lists := start(t, e, crowdSecParams())
wantDecision(t, lists, suspect,
reputation.Decision{Expires: began.Add(4 * time.Hour), Scenario: probing})
wantDecision(t, lists, "198.51.100.130",
reputation.Decision{Expires: began.Add(3 * time.Hour), Scenario: probing})
wantDecision(t, lists, "192.0.2.20",
reputation.Decision{Expires: began.Add(5 * time.Hour), Scenario: probing})
})
}
func TestCrowdSecAnswerOfNoDecisionIsAGoodCopyThatListsNoClient(t *testing.T) {
t.Parallel()
synctest.Test(t, func(t *testing.T) {
began := time.Now()
e := &engine{key: engineKey, decisions: []decision{
{"Ip", suspect, ban, sshBF, began.Add(4 * time.Hour)},
}}
lists := start(t, e, crowdSecParams())
// With its decision deleted, the engine answers null.
e.set(func(e *engine) { e.decisions = nil })
time.Sleep(time.Minute)
wantEngineFetches(t, e, 2)
want := []reputation.List{{
URL: decisionsURL, Tried: time.Now(), Fetched: time.Now(), Lines: []string{"null"},
}}
if got := lists.Snapshot(); !reflect.DeepEqual(got, want) {
t.Errorf("lists %+v, want %+v", got, want)
}
if lists.Failures(decisionsURL) != 0 {
t.Errorf("%d failures, want 0", lists.Failures(decisionsURL))
}
wantDecision(t, lists, suspect, reputation.Decision{})
})
}
func TestCrowdSecFailureKeepsTheLastGoodCopyAlertsOncePerCooldownAndHidesTheKey(
t *testing.T,
) {
t.Parallel()
for _, tc := range crowdSecFailures() {
t.Run(tc.name, func(t *testing.T) {
t.Parallel()
synctest.Test(t, func(t *testing.T) {
var log bytes.Buffer
began := time.Now()
e := &engine{key: engineKey, decisions: []decision{
{"Ip", suspect, ban, sshBF, began.Add(4 * time.Hour)},
}}
queue := newQueue()
p := crowdSecParams()
p.ProcessLog = slog.New(slog.NewJSONHandler(&log, nil))
p.Alerts = queue
lists := start(t, e, p)
kept := lists.Snapshot()
e.set(tc.fail)
// Each failure is tried again a minute after it.
for range 2 {
time.Sleep(time.Minute)
synctest.Wait()
}
wantEngineFetches(t, e, 3)
wantDecision(t, lists, suspect,
reputation.Decision{Expires: began.Add(4 * time.Hour), Scenario: sshBF})
want := kept[0]
want.Tried = time.Now()
if got := lists.Snapshot(); !reflect.DeepEqual(got, []reputation.List{want}) {
t.Errorf("lists %+v, want the first copy, last tried now, %+v", got, want)
}
if lists.Failures(decisionsURL) != 2 {
t.Errorf("%d failures, want 2", lists.Failures(decisionsURL))
}
// One alert for the first failure; the cooldown holds back the
// second.
wantAlert(t, queue,
fetchFailure(time.Now().Add(-time.Minute), decisionsURL, tc.error))
if !strings.Contains(log.String(), `"msg":"fetching a list failed",`+
`"url":"`+decisionsURL+`","error":"`+tc.error) {
t.Errorf("logged\n%s\nwant the failures", log.String())
}
wantKeyNotShown(t, e, log.String(), lists, queue)
})
})
}
}
// crowdSecFailure is a way for the engine to fail: fail has it answer the
// fetches after the first so that they fail with error.
type crowdSecFailure struct {
name string
fail func(e *engine)
error string
}
// crowdSecFailures returns the ways the engine can fail.
func crowdSecFailures() []crowdSecFailure {
const notDecision = " does not give an address or a netblock and a duration, " +
"such as 4h0m0s"
return []crowdSecFailure{
{
"an answer other than 200",
func(e *engine) { e.failing = true },
"the server answered 503 Service Unavailable",
},
{
"a key the engine refuses",
func(e *engine) { e.key = "another-key-0123456789abcdef" },
"the server answered 403 Forbidden",
},
{
"a redirect",
func(e *engine) { e.redirect = "http://elsewhere.example/v1/decisions" },
"the server answered 302 Found",
},
{
"an answer that does not read",
func(e *engine) { e.answer = "<html>" },
"read the answer: invalid character '<' looking for beginning of value",
},
{
"a decision to ban whose value does not read",
func(e *engine) {
e.answer = `[{"duration": "4h", "scenario": "` + sshBF + `", ` +
`"scope": "Ip", "type": "ban", "value": "203.0.113.300"}]`
},
"decision 1" + notDecision,
},
{
"a decision to ban whose duration does not read",
func(e *engine) {
e.answer = `[{"duration": "4h", "scope": "Country", "type": "ban", ` +
`"value": "KP"}, {"duration": "four hours", "scope": "Range", ` +
`"type": "ban", "value": "198.51.100.0/24"}]`
},
"decision 2" + notDecision,
},
}
}
// wantKeyNotShown checks that no fetch carried the engine's key to a URL
// other than its decision list, such as the one a redirect names, and that
// the key is in none of what the fetches leave behind: log, the process
// log, the alerts waiting in queue, and the copies of lists, which
// reputation.json keeps.
func wantKeyNotShown(
t *testing.T, e *engine, log string, lists *reputation.Lists, queue *alerts.Queue,
) {
t.Helper()
e.mu.Lock()
keySentTo := e.keySentTo
e.mu.Unlock()
if len(keySentTo) != 0 {
t.Errorf("the key was sent to %v", keySentTo)
}
shown, err := json.Marshal([]any{lists.Snapshot(), waiting(queue)})
if err != nil {
t.Fatalf("encode: %v", err)
}
if strings.Contains(log+string(shown), engineKey) {
t.Errorf("the key is shown in\n%s\n%s", log, shown)
}
}
func TestCrowdSecDecisionListKeptAcrossARestartEndsWhenItsDecisionsDo(t *testing.T) {
t.Parallel()
synctest.Test(t, func(t *testing.T) {
began := time.Now()
e := &engine{key: engineKey, decisions: []decision{
{rangeScope, "198.51.100.0/24", ban, probing, began.Add(time.Hour)},
}}
lists := start(t, e, crowdSecParams())
kept := lists.Snapshot()
// Restarted half an hour later with what reputation.json keeps, and
// the engine down, the decision still bans, until the end it had at
// the fetch, half an hour on.
time.Sleep(30 * time.Minute)
down := &engine{key: engineKey, failing: true}
again := reputation.New(crowdSecParams())
again.SetTransport(down)
err := again.Load(kept)
if err != nil {
t.Fatalf("load: %v", err)
}
run(t, again)
want := reputation.Decision{Expires: began.Add(time.Hour), Scenario: probing}
wantDecision(t, again, "198.51.100.7", want)
time.Sleep(30*time.Minute - time.Nanosecond)
synctest.Wait()
wantDecision(t, again, "198.51.100.7", want)
time.Sleep(time.Nanosecond)
synctest.Wait()
wantDecision(t, again, "198.51.100.7", reputation.Decision{})
})
}
func TestLoadTakesACrowdSecListNeverFetchedAndRefusesACopyThatDoesNotRead(
t *testing.T,
) {
t.Parallel()
now := time.Date(2026, 10, 6, 0, 0, 0, 0, time.UTC)
lists := reputation.New(crowdSecParams())
// Tried, and never fetched: there is no copy to read.
err := lists.Load([]reputation.List{{URL: decisionsURL, Tried: now}})
if err != nil {
t.Errorf("load the list never fetched: %v", err)
}
err = lists.Load([]reputation.List{{
URL: decisionsURL, Tried: now, Fetched: now, Lines: []string{
`[{"duration": "4h", "scope": "Range", "type": "ban", ` +
`"value": "198.51.100.0/33"}]`,
},
}})
const want = "the copy of " + decisionsURL + ": decision 1 does not give an " +
"address or a netblock and a duration, such as 4h0m0s"
if err == nil || err.Error() != want {
t.Errorf("error %v, want %s", err, want)
}
}
// engine is a stand-in for the local API of a CrowdSec engine. It answers
// a fetch of the decision list that carries its key in X-Api-Key with its
// decisions still in force, each with the time it has left as it answers,
// by the bubble's clock, as an engine does, or with answer while that is
// not "". It answers 403 to a fetch without its key, as an engine does,
// with a redirect to redirect while that is not "", and 503 while failing.
// It counts the fetches, and notes in keySentTo the URL of each fetch of
// another URL that carries a key, as one following a redirect would.
type engine struct {
mu sync.Mutex
key string
decisions []decision
answer string
redirect string
failing bool
fetches int
keySentTo []string
}
// decision is a decision of the engine, which ends at expires.
type decision struct {
scope, value, kind, scenario string
expires time.Time
}
// RoundTrip has the engine answer req, in place of the network.
func (e *engine) RoundTrip(req *http.Request) (*http.Response, error) {
e.mu.Lock()
defer e.mu.Unlock()
e.fetches++
if req.URL.String() != decisionsURL && req.Header.Get("X-Api-Key") != "" {
e.keySentTo = append(e.keySentTo, req.URL.String())
}
status, header, body := http.StatusOK, http.Header{}, e.answer
switch {
case req.URL.String() != decisionsURL || req.Header.Get("X-Api-Key") != e.key:
status, body = http.StatusForbidden, `{"message":"access forbidden"}`
case e.redirect != "":
status, header = http.StatusFound, http.Header{"Location": {e.redirect}}
case e.failing:
status, body = http.StatusServiceUnavailable, ""
case body == "":
body = e.inForce(time.Now())
}
return &http.Response{
StatusCode: status,
Status: fmt.Sprintf("%d %s", status, http.StatusText(status)),
Header: header,
Body: io.NopCloser(strings.NewReader(body)),
Request: req,
}, nil
}
// inForce returns the decisions in force at now, as the engine answers
// them: a JSON list, null for none.
func (e *engine) inForce(now time.Time) string {
var answer []map[string]string
for _, d := range e.decisions {
if now.Before(d.expires) {
answer = append(answer, map[string]string{
"duration": d.expires.Sub(now).String(), "origin": "crowdsec",
"scenario": d.scenario, "scope": d.scope, "type": d.kind, "value": d.value,
})
}
}
body, err := json.Marshal(answer)
if err != nil {
panic(err) // a list of maps of strings always encodes
}
return string(body)
}
// set changes the engine with change.
func (e *engine) set(change func(e *engine)) {
e.mu.Lock()
defer e.mu.Unlock()
change(e)
}
// crowdSecParams returns the Params of the decision list of the tests'
// engine, fetched with its key, by the bubble's clock, with alerts to a
// queue that sends none.
func crowdSecParams() reputation.Params {
p := params()
p.CrowdSecDecisionsURL = decisionsURL
p.CrowdSecKey = engineKey
return p
}
// wantEngineFetches waits until Run has made the fetches due, and checks
// how many the engine has had.
func wantEngineFetches(t *testing.T, e *engine, want int) {
t.Helper()
synctest.Wait()
e.mu.Lock()
got := e.fetches
e.mu.Unlock()
if got != want {
t.Errorf("%d fetches, want %d", got, want)
}
}
// wantDecision checks the decision lists says is in force on addr now,
// the zero Decision for none.
func wantDecision(
t *testing.T, lists *reputation.Lists, addr string, want reputation.Decision,
) {
t.Helper()
got, listed := lists.CrowdSecDecision(netip.MustParseAddr(addr), time.Now())
if listed != !want.Expires.IsZero() ||
listed && (!got.Expires.Equal(want.Expires) || got.Scenario != want.Scenario) {
t.Errorf("%s has the decision %+v in force %t, want %+v", addr, got, listed, want)
}
}
internal/reputation/export_test.go
+1
View File
@@ -11,6 +11,7 @@ import (
// network.
func (l *Lists) SetTransport(transport http.RoundTripper) {
l.httpClient.Transport = transport
l.crowdSecClient.Transport = transport
}
// SetTransport has a's checks go through transport instead of the
internal/reputation/reputation.go
+174 -31
View File
@@ -1,8 +1,9 @@
// Package reputation fetches the lists the settings name by URL: the
// blocklists of SWWAF_BLOCKLIST_URLS, and the file of AS:percent lines
// SWWAF_ASN_LIMIT_PERCENT_URL names. It keeps the last good copy of each,
// whole, comment lines included, which is used while a fetch fails, and
// when each was last tried. It also asks the DNSBL zones of
// blocklists of SWWAF_BLOCKLIST_URLS, the file of AS:percent lines
// SWWAF_ASN_LIMIT_PERCENT_URL names, and the decision list of the CrowdSec
// engine SWWAF_CROWDSEC_LAPI_URL names. It keeps the last good copy of
// each, whole, comment lines included, which is used while a fetch fails,
// and when each was last tried. It also asks the DNSBL zones of
// SWWAF_DNSBL_ZONES about clients, and keeps their verdicts, and checks
// clients with AbuseIPDB, and keeps their scores and the checks spent
// today. The state package writes all of these to reputation.json and
@@ -11,6 +12,7 @@ package reputation
import (
"context"
"encoding/json"
"errors"
"fmt"
"io"
@@ -32,6 +34,10 @@ const (
maxListBytes = 16 << 20
// fetchTimeout bounds one fetch of a list.
fetchTimeout = time.Minute
// crowdSecRefresh is how long after the CrowdSec decision list was last
// fetched or tried it is fetched again: the engine is the operator's
// own, and makes and ends decisions all the time.
crowdSecRefresh = time.Minute
// mappedBits is the length of ::ffff:0.0.0.0/96, the netblock of every
// IPv4-mapped address.
mappedBits = 96
@@ -43,6 +49,8 @@ var (
errNotNetblock = errors.New("is not an address or a netblock, such as 192.0.2.0/24")
errNotASNPercent = errors.New(
"is not an AS number, : and a percentage, such as AS64496:50")
errNotDecision = errors.New(
"does not give an address or a netblock and a duration, such as 4h0m0s")
)
// List is a list as reputation.json holds it: the URL it is fetched from,
@@ -63,8 +71,14 @@ type Params struct {
// (SWWAF_ASN_LIMIT_PERCENT_URL), "" while it is unset.
BlocklistURLs []string
ASNLimitPercentURL string
// CrowdSecDecisionsURL is the CrowdSec decision list, "" while
// SWWAF_CROWDSEC_LAPI_URL is unset, fetched with CrowdSecKey
// (SWWAF_CROWDSEC_LAPI_KEY).
CrowdSecDecisionsURL string
CrowdSecKey string
// Refresh is how long after a list was last fetched or tried it is
// fetched again (SWWAF_BLOCKLIST_REFRESH).
// fetched again (SWWAF_BLOCKLIST_REFRESH), but for the CrowdSec decision
// list, which is fetched again crowdSecRefresh after.
Refresh time.Duration
// Now tells the time, normally time.Now in UTC.
Now func() time.Time
@@ -79,6 +93,10 @@ type Params struct {
type Lists struct {
params Params
httpClient *http.Client
// crowdSecClient fetches the CrowdSec decision list. It follows no
// redirect, so that the key goes to the engine alone: a redirect is a
// failure.
crowdSecClient *http.Client
mu sync.Mutex
// lists are by URL, one for each URL Params names.
@@ -95,17 +113,36 @@ type list struct {
}
// entries are what the lines of a copy say: for a blocklist, the netblocks
// it names, with the lengths among them, and for the file of AS:percent
// lines, the percentage it gives each AS number.
// it names, with the lengths among them, for the file of AS:percent lines,
// the percentage it gives each AS number, and for the CrowdSec decision
// list, the decision on each netblock that ends last, with the lengths
// among them.
type entries struct {
netblocks map[netip.Prefix]bool
lengths []int
percents map[string]int64
decisions map[netip.Prefix]Decision
}
// Decision is a decision of the CrowdSec engine to ban a netblock: when
// it ends, and the scenario that made it, such as crowdsecurity/ssh-bf.
type Decision struct {
Expires time.Time
Scenario string
}
// New returns the lists, without a copy of any yet.
func New(params Params) *Lists {
l := &Lists{params: params, httpClient: &http.Client{}, lists: map[string]*list{}}
l := &Lists{
params: params,
httpClient: &http.Client{},
crowdSecClient: &http.Client{
CheckRedirect: func(*http.Request, []*http.Request) error {
return http.ErrUseLastResponse
},
},
lists: map[string]*list{},
}
for _, listURL := range l.URLs() {
l.lists[listURL] = &list{kept: List{URL: listURL}}
@@ -115,13 +152,18 @@ func New(params Params) *Lists {
}
// URLs returns the URL of every list: the blocklists' in the order
// SWWAF_BLOCKLIST_URLS names them, then SWWAF_ASN_LIMIT_PERCENT_URL.
// SWWAF_BLOCKLIST_URLS names them, then SWWAF_ASN_LIMIT_PERCENT_URL, then
// the CrowdSec decision list's.
func (l *Lists) URLs() []string {
urls := slices.Clone(l.params.BlocklistURLs)
if l.params.ASNLimitPercentURL != "" {
urls = append(urls, l.params.ASNLimitPercentURL)
}
if l.params.CrowdSecDecisionsURL != "" {
urls = append(urls, l.params.CrowdSecDecisionsURL)
}
return urls
}
@@ -157,6 +199,37 @@ func (l *Lists) ASNLimitPercent(asn string) (int64, bool) {
return percent, listed
}
// CrowdSecDecision returns the decision of the copy of the CrowdSec
// decision list on a netblock that holds addr and that ends last, and
// whether it is still in force at now. A decision that has ended no
// longer bans, even before the next fetch drops it.
func (l *Lists) CrowdSecDecision(addr netip.Addr, now time.Time) (Decision, bool) {
if l.params.CrowdSecDecisionsURL == "" {
return Decision{}, false
}
l.mu.Lock()
defer l.mu.Unlock()
kept := l.lists[l.params.CrowdSecDecisionsURL].entries
var last Decision
for _, length := range kept.lengths {
netblock, err := addr.Prefix(length)
if err != nil {
continue // an IPv6 netblock's length, past an IPv4 address's 32 bits
}
decision := kept.decisions[netblock]
if decision.Expires.After(last.Expires) {
last = decision
}
}
return last, now.Before(last.Expires)
}
// Fetched returns when the copy in use of the list at listURL was
// fetched, or zero while there is none.
func (l *Lists) Fetched(listURL string) time.Time {
@@ -174,10 +247,9 @@ func (l *Lists) Failures(listURL string) int {
return l.lists[listURL].failures
}
// Run fetches each list once Refresh has passed since it was last fetched
// or tried, the later of the two, until ctx is done. A list never tried is
// fetched at once, and so is one whose last try or copy, read from
// reputation.json, is that old.
// Run fetches each list once it is due, as due tells, until ctx is done. A
// list never tried is fetched at once, and so is one that is due by its
// last try or copy read from reputation.json.
func (l *Lists) Run(ctx context.Context) {
if len(l.lists) == 0 {
return
@@ -225,11 +297,12 @@ func (l *Lists) Load(lists []List) error {
found := make(map[string]entries, len(lists))
for _, kept := range lists {
if _, named := l.lists[kept.URL]; !named {
continue
_, named := l.lists[kept.URL]
if !named || kept.Fetched.IsZero() {
continue // dropped, or a list tried but never fetched, without a copy
}
read, err := l.parse(kept.URL, kept.Lines)
read, err := l.parse(kept.URL, kept.Lines, kept.Fetched)
if err != nil {
return fmt.Errorf("the copy of %s: %w", kept.URL, err)
}
@@ -245,9 +318,8 @@ func (l *Lists) Load(lists []List) error {
}
for _, kept := range lists {
read, named := found[kept.URL]
if named {
l.lists[kept.URL].kept, l.lists[kept.URL].entries = kept, read
if _, named := l.lists[kept.URL]; named {
l.lists[kept.URL].kept, l.lists[kept.URL].entries = kept, found[kept.URL]
}
}
@@ -276,7 +348,8 @@ func (l *Lists) fetchDue(ctx context.Context) time.Time {
}
// due returns when the list at listURL is to be fetched: Refresh after it
// was last fetched or tried, the later of the two.
// was last fetched or tried, the later of the two, or crowdSecRefresh
// after for the CrowdSec decision list.
func (l *Lists) due(listURL string) time.Time {
l.mu.Lock()
defer l.mu.Unlock()
@@ -288,6 +361,10 @@ func (l *Lists) due(listURL string) time.Time {
last = held.kept.Tried
}
if listURL == l.params.CrowdSecDecisionsURL {
return last.Add(crowdSecRefresh)
}
return last.Add(l.params.Refresh)
}
@@ -298,14 +375,14 @@ func (l *Lists) due(listURL string) time.Time {
// so that a restart waits for it: the server may have had its request.
func (l *Lists) fetch(ctx context.Context, listURL string) {
lines, err := l.get(ctx, listURL)
now := l.params.Now()
var found entries
if err == nil {
found, err = l.parse(listURL, lines)
found, err = l.parse(listURL, lines, now)
}
cutOff := err != nil && ctx.Err() != nil
now := l.params.Now()
l.mu.Lock()
@@ -350,8 +427,11 @@ func raiseFailure(queue *alerts.Queue, reason, source string, err error) {
})
}
// get fetches the list at listURL, and returns its lines. An answer other
// than 200, or a list longer than maxListBytes, is a failure.
// get fetches the list at listURL, and returns its lines. The CrowdSec
// decision list is fetched with CrowdSecKey in the header X-Api-Key, where
// the engine looks for it, by crowdSecClient, which follows no redirect.
// An answer other than 200, or a list longer than maxListBytes, is a
// failure.
func (l *Lists) get(ctx context.Context, listURL string) ([]string, error) {
ctx, cancel := context.WithTimeout(ctx, fetchTimeout)
defer cancel()
@@ -361,7 +441,14 @@ func (l *Lists) get(ctx context.Context, listURL string) ([]string, error) {
return nil, fmt.Errorf("make the request: %w", err)
}
res, err := l.httpClient.Do(req)
client := l.httpClient
if listURL == l.params.CrowdSecDecisionsURL {
req.Header.Set("X-Api-Key", l.params.CrowdSecKey)
client = l.crowdSecClient
}
res, err := client.Do(req)
if err != nil {
// Do's error names the URL, which the log line and the alert name
// already: only what went wrong is kept.
@@ -393,16 +480,22 @@ func (l *Lists) get(ctx context.Context, listURL string) ([]string, error) {
return lines, nil
}
// parse reads the lines of the list at listURL: those of a blocklist, or
// of the file of AS:percent lines. Anything after a ; or a # on a line is
// parse reads the lines of the list at listURL, fetched at fetched: those
// of a blocklist, of the file of AS:percent lines, or of the CrowdSec
// decision list. In the first two, anything after a ; or a # on a line is
// left out, and so is a line left blank. Any other line that does not read
// is an error naming it by its number.
func (l *Lists) parse(listURL string, lines []string) (entries, error) {
if listURL == l.params.ASNLimitPercentURL {
func (l *Lists) parse(
listURL string, lines []string, fetched time.Time,
) (entries, error) {
switch listURL {
case l.params.ASNLimitPercentURL:
return parsePercents(lines)
case l.params.CrowdSecDecisionsURL:
return parseDecisions(lines, fetched)
default:
return parseNetblocks(lines)
}
return parseNetblocks(lines)
}
// parseNetblocks reads a blocklist's lines, each an address or a netblock
@@ -486,6 +579,56 @@ func parsePercents(lines []string) (entries, error) {
return found, nil
}
// parseDecisions reads the lines of the CrowdSec decision list fetched at
// fetched: the engine's answer, a JSON list of its decisions in force,
// null while it has none. A decision of the type ban whose scope is Ip or
// Range, as CrowdSec names them, bans its value, an address or a netblock
// as parseNetblock reads it, until its duration, the time it had left as
// the engine answered, has passed since fetched. Any other decision, such
// as one to show a captcha or one on a country, is left out. A decision
// to ban whose value or duration does not read is an error naming it by
// its number.
func parseDecisions(lines []string, fetched time.Time) (entries, error) {
var answer []struct {
Duration string `json:"duration"`
Scenario string `json:"scenario"`
Scope string `json:"scope"`
Type string `json:"type"`
Value string `json:"value"`
}
err := json.Unmarshal([]byte(strings.Join(lines, "\n")), &answer)
if err != nil {
return entries{}, fmt.Errorf("read the answer: %w", err)
}
found := entries{decisions: map[netip.Prefix]Decision{}}
for i, decision := range answer {
if decision.Type != "ban" || (decision.Scope != "Ip" && decision.Scope != "Range") {
continue
}
netblock, ok := parseNetblock(decision.Value)
duration, err := time.ParseDuration(decision.Duration)
if !ok || err != nil {
return entries{}, fmt.Errorf("decision %d %w", i+1, errNotDecision)
}
expires := fetched.Add(duration)
if expires.After(found.decisions[netblock].Expires) {
found.decisions[netblock] = Decision{Expires: expires, Scenario: decision.Scenario}
}
if !slices.Contains(found.lengths, netblock.Bits()) {
found.lengths = append(found.lengths, netblock.Bits())
}
}
return found, nil
}
// withoutComment returns line without anything after a ; or a #, and
// without the spaces around what is left.
func withoutComment(line string) string {
internal/reputation/reputation_test.go
+15 -7
View File
@@ -215,12 +215,7 @@ func TestFailedFetchKeepsTheLastGoodCopyAndAlertsOncePerCooldown(t *testing.T) {
// One alert for the first failure; the cooldown holds back the
// second.
wantAlert(t, queue, alerts.Alert{
Time: time.Now().Add(-refresh),
Event: alerts.EventSourceFailure,
Reason: "fetching a list failed",
Detail: map[string]any{"source": dropURL, "error": tc.error},
})
wantAlert(t, queue, fetchFailure(time.Now().Add(-refresh), dropURL, tc.error))
if !strings.Contains(log.String(), `"msg":"fetching a list failed",`+
`"url":"`+dropURL+`","error":"`+tc.error) {
@@ -535,7 +530,9 @@ func newQueue() *alerts.Queue {
// start returns the lists of p, fetched through servers by Run, which runs
// until the test ends, once Run has fetched those due at start.
func start(t *testing.T, servers *standIn, p reputation.Params) *reputation.Lists {
func start(
t *testing.T, servers http.RoundTripper, p reputation.Params,
) *reputation.Lists {
t.Helper()
lists := reputation.New(p)
@@ -597,6 +594,17 @@ func waiting(queue *alerts.Queue) []alerts.Alert {
return queue.Snapshot().Waiting[alerts.DestinationWebhook]
}
// fetchFailure is the source_failure alert raised at the time raised for
// a fetch of the list at listURL that failed with err.
func fetchFailure(raised time.Time, listURL, err string) alerts.Alert {
return alerts.Alert{
Time: raised,
Event: alerts.EventSourceFailure,
Reason: "fetching a list failed",
Detail: map[string]any{"source": listURL, "error": err},
}
}
// wantAlert checks that want is the one alert waiting in queue, and that
// the cooldown has held back one repeat of it.
func wantAlert(t *testing.T, queue *alerts.Queue, want alerts.Alert) {
internal/requestlog/requestlog.go
+5 -3
View File
@@ -29,7 +29,8 @@ const (
// over a rate limit, which bans the client.
ActionRateLimited = "rate_limited"
// ActionBanned is a request refused because a ban covers its client,
// or because it matched a ban rule, which bans the client.
// or because it matched a ban rule or the CrowdSec decision list lists
// its client, either of which bans the client.
ActionBanned = "banned"
// ActionRuleBlocked is a request refused because it matched a block
// rule.
@@ -140,8 +141,9 @@ type Line struct {
// minute_bytes, hour_bytes or day_bytes for a byte limit.
LimitHit string `json:"limit_hit,omitempty"`
// Reputation are the URLs of the blocklists that list the client, then
// the DNSBL zones whose verdict lists it, their keys masked, then
// abuseipdb when its score is a hit.
// that of the CrowdSec decision list when it does, then the DNSBL zones
// whose verdict lists it, their keys masked, then abuseipdb when its
// score is a hit.
Reputation []string `json:"reputation,omitempty"`
// Offence is the offence the request was held as, OffenceLimit.
Offence string `json:"offence,omitempty"`
internal/smallwebwaf/smallwebwaf_test.go
+74
View File
@@ -716,6 +716,80 @@ func TestBlocklistTriesAndCopiesKeptInReputationJSONAcrossRestarts(t *testing.T)
}
}
func TestCrowdSecDecisionListKeptInReputationJSONAcrossARestart(t *testing.T) {
t.Parallel()
const bouncerKey = "crowdsec-key-0123456789abcdef"
// A stand-in for the engine's local API, which bans 203.0.113.0/24 for
// four hours, and answers only a request with its key, while it is up.
down := new(atomic.Bool)
engine := httptest.NewServer(http.HandlerFunc(
func(w http.ResponseWriter, r *http.Request) {
switch {
case r.URL.Path != "/v1/decisions" || r.Header.Get("X-Api-Key") != bouncerKey:
w.WriteHeader(http.StatusForbidden)
case down.Load():
w.WriteHeader(http.StatusServiceUnavailable)
default:
_, _ = io.WriteString(w, `[{"duration": "4h0m0s", "origin": "crowdsec", `+
`"scenario": "crowdsecurity/http-probing", "scope": "Range", `+
`"type": "ban", "value": "203.0.113.0/24"}]`)
}
}))
t.Cleanup(engine.Close)
dir := t.TempDir()
env := map[string]string{
listenAddr: localhost + ":0",
upstreamURL: startApp(t),
stateDir: dir,
rulesDir: t.TempDir(),
trustedProxies: localhost + "/32",
"SWWAF_CROWDSEC_LAPI_URL": engine.URL,
"SWWAF_CROWDSEC_LAPI_KEY": bouncerKey,
}
// Once the list is fetched, the client's request bans it.
first := runUntilStopped(t, env, func(url string) {
for statusFrom(t, url, placed) != http.StatusForbidden {
time.Sleep(pollInterval)
}
})
ban := onlyBan(t, dir)
if ban["netblock"] != placed+"/32" || ban["cause"] != "crowdsec" ||
ban["reason"] != "CrowdSec's decision for crowdsecurity/http-probing" {
t.Errorf("bans.json holds %v, want the ban for crowdsec on %s", ban, placed)
}
// Restarted with the engine down, the copy kept in reputation.json bans
// another client in the netblock from its first request.
down.Store(true)
second := runUntilStopped(t, env, func(url string) {
wantStatus(t, url, "203.0.113.10", http.StatusForbidden)
})
// The key is in neither run's output, nor in a state file.
files := []string{"bans.json", "reputation.json", "clients.json"}
shown := make([]string, 0, len(files)+2)
shown = append(shown, first.text(), second.text())
for _, name := range files {
data, err := os.ReadFile(filepath.Join(dir, name)) //nolint:gosec // the test's
if err != nil {
t.Fatalf("read %s: %v", name, err)
}
shown = append(shown, string(data))
}
if all := strings.Join(shown, "\n"); strings.Contains(all, bouncerKey) {
t.Errorf("the key is shown in the output or the state files:\n%s", all)
}
}
// wantDeniedByList checks that the request log line is of a request the
// blocklist at listURL refused.
func wantDeniedByList(t *testing.T, line map[string]any, listURL string) {
internal/state/state.go
+4 -3
View File
@@ -60,7 +60,7 @@ var (
errVersion = errors.New("unknown version")
// errMissing is for an entry without a field it needs.
errMissing = errors.New("has no")
errCause = errors.New("is not limit, attack or admin")
errCause = errors.New("is not limit, attack, admin or crowdsec")
errDestination = errors.New("is not webhook, slack or ntfy")
errScope = errors.New("is not client, net, asn, total or watch")
errWaitingList = errors.New(`waiting is a list, but now lists the alerts by ` +
@@ -647,7 +647,7 @@ func (e BanEntry) ban() bans.Ban {
// worked out, or an expires, which would make it permanent. A permanent
// ban's expires is null, which Bans cannot tell from a missing one, so
// each expires is read again as written. A cause other than limit,
// attack or admin, most likely misspelt, is refused too.
// attack, admin or crowdsec, most likely misspelt, is refused too.
func (f *bansFile) check(data []byte) error {
var written struct {
Bans []struct {
@@ -669,7 +669,8 @@ func (f *bansFile) check(data []byte) error {
case written.Bans[i].Expires == nil:
return missing(i, "expires")
case entry.Cause != "" && entry.Cause != bans.CauseLimit &&
entry.Cause != bans.CauseAttack && entry.Cause != bans.CauseAdmin:
entry.Cause != bans.CauseAttack && entry.Cause != bans.CauseAdmin &&
entry.Cause != bans.CauseCrowdSec:
return fmt.Errorf("entry %d's cause %q %w", i+1, entry.Cause, errCause)
}
}
internal/state/state_test.go
+11 -5
View File
@@ -97,7 +97,8 @@ const permanentBansJSON = `{
"earlier_bans": {
"limit": 3,
"attack": 1,
"admin": 1
"admin": 1,
"crowdsec": 2
}
}
}
@@ -849,8 +850,10 @@ func TestBanWithAnotherCauseStopsTheStart(t *testing.T) {
`{"netblock": "203.0.113.10/32", "start": "2026-10-06T00:00:00Z", `+
`"expires": null, "cause": "admin"}, `+
`{"netblock": "203.0.113.11/32", "start": "2026-10-06T00:00:00Z", `+
`"expires": "2026-10-06T04:00:00Z", "cause": "crowdsec"}, `+
`{"netblock": "203.0.113.12/32", "start": "2026-10-06T00:00:00Z", `+
`"expires": null, "cause": "atack"}]}`,
`: entry 3's cause "atack" is not limit, attack or admin`)
`: entry 4's cause "atack" is not limit, attack, admin or crowdsec`)
}
func TestUnknownVersionStopsTheStart(t *testing.T) {
@@ -1726,8 +1729,9 @@ func office() netip.Prefix {
return netip.MustParsePrefix("203.0.113.0/24")
}
// fill puts a permanent ban an admin made, a ban for a broken limit and
// one for a clear sign of attack, clients with counts and histories,
// fill puts a permanent ban an admin made, a ban for a broken limit, one
// for a clear sign of attack and one for CrowdSec's decision, clients
// with counts and histories,
// GeoJS answers, the blocklists' last tries and the copy of one, two
// verdicts of a DNSBL zone, and the AbuseIPDB checks spent today with two
// scores, as filledReputationJSON holds them, and alerts
@@ -1743,6 +1747,8 @@ func fill(params state.Params) {
})
params.Ledger.BanForAttack(netip.MustParsePrefix("192.0.2.1/32"), now,
bans.Notes{RuleID: "env-file", Target: "path"})
params.Ledger.BanForCrowdSec(netip.MustParsePrefix("198.51.100.9/32"), now,
now.Add(4*time.Hour), "crowdsecurity/ssh-bf", bans.Notes{})
for _, c := range []string{"2001:db8::/64", "203.0.113.9/32", "192.0.2.1/32"} {
params.Limiter.Count(netip.MustParsePrefix(c), now, whole)
@@ -1844,7 +1850,7 @@ func permanentBan() bans.Ban {
},
Requests: 1500,
Refused: 3,
EarlierBans: bans.EarlierBans{Limit: 3, Attack: 1, Admin: 1},
EarlierBans: bans.EarlierBans{Limit: 3, Attack: 1, Admin: 1, CrowdSec: 2},
},
}
}