Files
smallwebwaf/internal/discriminator/refusallimit.go
T
sneak d282a737a8
check / check (push) Successful in 4m46s
Read every setting through viper and rename the settings (closes #211)
Every setting of discriminator and rproxy is read through viper, in place
of the os.LookupEnv function Main passed down. NewViper turns AutomaticEnv
and AllowEmptyEnv on, so a setting that is set but empty reads as set. A
setting may also be given as a file, the _FILE form, which rproxy's
settings now have too; rproxy still writes nothing to disk.

The settings are renamed. Discriminator's take the prefix SWW_WAF_,
rproxy's take SWW_RPROXY_, and the shared SWW_COMMAND keeps SWW_. The Core
Rule Set's settings take SWW_WAF_CORE_RULE_SET_ rather than SWW_WAF_WAF_.

Model: deepseek-v4-pro (first version); opus-5-5 (rework)
2026-11-09 06:20:26 +00:00

55 lines
1.6 KiB
Go

package discriminator
// The heuristic refusal_limit. It reads SWW_WAF_ERROR_BURST_THRESHOLD and
// SWW_WAF_BAN_RESPONSE.
import (
"context"
"net/http"
"time"
"sneak.berlin/go/smallwebwaf/internal/requestlog"
)
// refusalLimit counts the request once it has been answered, if discriminator
// refused it after a rule file match, a trap path or a Core Rule Set match, and
// in observe mode if enforce mode would have: more than
// SWW_WAF_ERROR_BURST_THRESHOLD such refusals of the client within a minute break
// a limit, which bans the client. A client in SWW_WAF_ALLOW_NETS, which the
// heuristics skip, is not counted, and nothing is while the threshold is off.
// Its figures are the window, the count and the limit.
type refusalLimit struct{}
func (refusalLimit) name() string { return "refusal_limit" }
func (refusalLimit) check(_ context.Context, rq *request, now time.Time) *verdict {
cfg := rq.h.config
if cfg.ErrorBurstThreshold == 0 {
return nil
}
if !rq.attack && !rq.blockedByBlockRule && !rq.wafBlocked {
return nil
}
hit, over := rq.h.limiter.CountRefusal(rq.h.clientGroup(rq.client), now,
cfg.ErrorBurstThreshold)
if !over {
return nil
}
// What the client was sent, or in observe mode would have been.
status := rq.out.status
switch rq.line.WouldAction {
case requestlog.ActionBlockedByBlockRule, requestlog.ActionWAFBlocked:
status = http.StatusForbidden
case requestlog.ActionTemporarilyBanned, requestlog.ActionPermanentlyBanned:
status = cfg.BanResponse
}
rq.banForLimit(now, hit, status)
return &verdict{figures: limitFigures(hit)}
}