Implement the structured send log (spec 7.3), the project's highest-risk
component since a milter bug can break the relay itself.
- internal/milter: go-milter v0.4.1 journal-milter. Per-connection session
collects SASL login, From, recipients and Subject across callbacks and
writes one send_log "queued" row per (queue-id, recipient) at EOM
(spec 7.3.3). Monitoring only: callbacks return Continue/Accept, recorder
errors are logged never propagated, so it can never block mail.
- internal/logtail: polling mail.log tailer with rotation handling (inode
change / truncation), parses sent/deferred/bounced/expired by queue-id +
recipient and advances rows; background retention sweep prunes rows past
SEND_LOG_RETENTION_DAYS (default 90) at startup and every 6h.
- internal/store/sendlog.go: InsertQueued, UpdateStatus (case-insensitive
recipient match), DeleteSendLogBefore + status constants.
- cmd/panel: open the store once and share it across http/milter/tailer;
replace the journal/logtail stubs with the real roles.
- build/postfix-config.sh: bounded milter timeouts (15/15/30s) so a hung
milter also fails open in seconds, not the 300s default.
Fix found in-container: SASL login (app_login) was empty because go-milter
keys macros exactly as Postfix sends them, and multi-character macro names
arrive brace-wrapped ({auth_authen}); the SASL-less Phase 0 spike could not
observe this. Added a brace-tolerant macro lookup.
Verified on selfpost.example.com: gofmt/vet/unit tests green; container e2e
records rows with correct fields and advances status via the tailer; fail-open
confirmed for both an unreachable and a hung milter; retention prunes at start.
Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>
Generate the relay config from the environment at container start
(build/postfix-config.sh, run from entrypoint.sh):
- smtps 465 (implicit TLS) primary + optional submission 587 (STARTTLS),
chroot=n so smtpd reaches the sasldb2/sender map under /data.
- Cyrus SASL against the panel-maintained sasldb2; realm left implicit so the
authenticated name equals the bare login in smtpd_sender_login_maps.
- reject_sender_login_mismatch + relay/recipient restrictions with no
permit_mynetworks: credentials-only, open relay impossible (spec 5, 5.1).
- TLS cert/key from TLS_CERT_FILE/TLS_KEY_FILE; daily postfix reload picks up
renewed certs (postfix-cert-reload.sh under supervisord, spec 5.2).
- anvil level-1 rate limit from env (spec 5 p.5).
- Milter chain with per-milter action: OpenDKIM strict (tempfail), journal
fail-open (accept) so monitoring never blocks the relay (spec 7.3).
Two integration fixes found on the server:
- postconf -F '*/*/chroot=n': Debian's chrooted delivery agent can't read
/etc/resolv.conf, so MX lookups failed and mail never left.
- entrypoint sets /run/opendkim and /run/selfpost to group selfpost + setgid,
and the journal stub chmods its socket 0660, so postfix can connect to both
milter sockets (strict OpenDKIM was milter-rejecting all mail otherwise).
Verified on selfpost.example.com: gofmt/vet/test green, image builds; container
e2e — 465 auth+send DKIM-signed (d=domain,s=selfpost), 587 STARTTLS auth,
cross-domain sender 553, list-mode per-address binding, unauth relay 554,
real outbound delivery reaching the recipient MX over TLS.
Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>
mix