Files
smallwebwaf/internal/proxy/bans.go
T
clawbot df2c5042d2
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Keep the bans, the clients and GeoJS's answers in state files (closes #17)
smallwebwaf now copies its state to bans.json, clients.json and
lookups.json in SWWAF_STATE_DIR, as "Persistent state" in SPEC.md
describes, and reads them back at start, so a restart lifts no ban and
gives no client a fresh allowance. Each client gains a history, and a
ban's notes count the netblock's requests. bans.json is written
SWWAF_STATE_WRITE_DELAY after a ban, and every file every
SWWAF_STATE_COUNTER_INTERVAL and at the stop. A ban read back is masked
to its netblock and refuses every client in it. A file that does not
parse, an unknown version, an entry without a field it needs, or an
unwritable directory stops the start.

Deviation: no AS number or name, and no ban cause, reason or lifting yet.

Model: opus-5-5
2026-10-06 08:31:52 +02:00

86 lines
2.2 KiB
Go

package proxy
import (
"net/netip"
"time"
"sneak.berlin/go/smallwebwaf/internal/bans"
"sneak.berlin/go/smallwebwaf/internal/requestlog"
)
// banResponse is a refusal answered with SWWAF_BAN_RESPONSE, and logged
// with action.
func (rq *request) banResponse(action string) *refusal {
return &refusal{status: rq.h.config.BanResponse, action: action}
}
// banned reports whether a ban on a netblock the client is in refuses
// the request at now, and notes for the log line when that ban ends.
func (rq *request) banned(now time.Time) bool {
ban, banned := rq.h.ledger.Check(rq.client, now)
if banned {
rq.line.BanExpires = banExpires(ban)
}
return banned
}
// limitBroken counts the request for the rate limits at now, and reports
// whether it takes the client over one. Such a request bans the client's
// netblock, and sets the client's counters back to zero.
func (rq *request) limitBroken(now time.Time) bool {
group := clientGroup(rq.client)
hit, over := rq.h.limiter.Count(group, now)
if !over {
return false
}
netblock := rq.netblock()
ban := rq.h.ledger.BanForLimit(netblock, now, bans.Notes{
Country: rq.line.Country,
Limit: hit.Limit,
Window: hit.Window,
Count: hit.Requests,
Request: bans.Request{
Time: now,
Method: rq.in.Method,
Host: rq.in.Host,
Path: rq.in.URL.RequestURI(),
Status: rq.h.config.BanResponse,
UserAgent: rq.in.UserAgent(),
},
// The histories count this request only once it has ended.
Requests: rq.h.limiter.Requests(netblock) + 1,
})
rq.h.limiter.Reset(group)
rq.line.LimitHit = hit.Window
rq.line.Offence = requestlog.OffenceLimit
rq.line.BanExpires = banExpires(ban)
return true
}
// netblock is the netblock a ban on the client covers: its IPv4 address,
// widened to SWWAF_BAN_SCOPE_V4_PREFIX, or the IPv6 group clientGroup
// counts it in.
func (rq *request) netblock() netip.Prefix {
addr := rq.client.Unmap()
if addr.Is4() {
return netip.PrefixFrom(addr, rq.h.config.BanScopeV4Prefix).Masked()
}
return clientGroup(addr)
}
// banExpires is when ban ends, as the log line gives it: a time, or
// permanent.
func banExpires(ban bans.Ban) string {
if ban.Permanent() {
return "permanent"
}
return requestlog.FormatTime(ban.Expires)
}