Invert level-2 semantics so domain limits apply to every client IP and
application limits with trusted IPs raise the ceiling above the domain
(still capped by level 1). Panel shows L1, validates maxima, and documents
the model on Settings.
Co-authored-by: Cursor <cursoragent@cursor.com>
The journal-milter, until now a pure monitor, now refuses a message with a
4xx tempfail (RespTempFail/451) at MAIL FROM when a per-domain or per-
application limit is exceeded. Key is the client IP; the count is
COUNT(DISTINCT queue_id) over a sliding window reusing the send log; the
limit applies only when a non-empty IP binding matches the client (empty
binding => level-1 only, per spec 7.4). Enforcement is fail-open on the
milter's own errors — a limiter malfunction never blocks mail, and Postfix's
level-1 anvil limit stays the independent backstop. Refused messages are
recorded in send_log with status "rejected" for UI visibility.
- store/ratelimits.go: RateLimit type (+Active/AllowsIP), id-keyed get/set/
delete for the panel, name/login-keyed lookup + windowed distinct-message
count for the milter, DeleteRateLimitsForDomain. No migration — the
rate_limits table has existed since Phase 2.
- milter: enforce at MailFrom, fail-open helper overLimit, InsertRejected.
- web: server-side validated IP/ceiling/window forms on the domain page and
per application; routes POST /domains/{id}/ratelimit and
/applications/{aid}/ratelimit. Milter reads rows live, so no reload.
- domain/app services clear limits on deletion (rate_limits has no FK cascade).
Unit tests + container e2e (p8) green: refusal on both scopes, unregistered
IP ignored, fail-open with the panel stopped.
Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>