A message's From: line is held against the application that sends it, under
the rule Postfix holds the envelope sender to. OpenDKIM chooses the key by
that line, so until now an application could have mail signed as another
domain of the server or as the server itself.
The check (internal/milter/sender.go)
- A role of the panel on a socket of its own (SENDER_CHECK_SOCKET), first in
smtpd_milters and strict: default_action=tempfail. The journal milter keeps
its socket and stays fail-open. postfix-wrapper waits for the new socket.
- It reads no database: what an application may send as comes from Postfix's
own sender_login_maps, what the server signs for from OpenDKIM's
SigningTable. Both are read again when they change; one that cannot be
read defers mail.
- One From: field, one address, allowed by the envelope's lookup; then no
other name of the SigningTable may appear anywhere in the raw line.
Refused: 550 5.7.1 naming the line, reduced to printable ASCII.
- A refusal is a send-log row with reason "from" and the header address
(migration 0006), written by another goroutine and not waited for. The
journal's refusals record their reason too (limit, client), and the
notifier takes only a limit's.
What it costs (docs/plans/from-header-binding.md, Statistics)
- The role marks itself alive every 2 s; at start the gap since the mark is
downtime, counted from Postfix's start if later and not at all when
supervisord says Postfix is not running.
- The log tailer counts the connections Postfix turned away: a warning that
names the socket, then milter-reject "Service unavailable" from the same
smtpd. Seen on the stand: the client is refused from CONNECT on and leaves
at AUTH (454), so no MAIL line is ever written.
- sender_check_days, a row per UTC day, kept a year.
Pages
- Health: the card "Sender check", the socket's row, and the cards layout -
boxes numbered by importance in two stacks read in rows; the left stack
polls, the three readings of the right one are swapped in by id.
- Outbound log: a refused row says why in its tag (wrong From, wrong client,
rate-limited); the message's page shows the From: line and what the
application may send as.
- Help: topic "Sender check", word for word the mockup's.
Found by the stand, fixed here: the names for the second look came from the
sender bindings, and a domain with a key and no application yet was not
among them.
e2e: negative_journal_milter_fail_open is gone - it proved that mail passes
with the panel down, which is no longer so. In its place
sender_check_holds_the_from_line (another domain's From:, the hostname's, a
stranger's, an address off the list, another sender in the display name -
refused; own addresses - delivered) and panel_down_defers_mail (4xx with the
panel stopped, the container alive, mail again after, downtime and one
deferred message on Health, the card warning).
Test server, this tree before the last cosmetic edits (a fixture row, a
fact's size, docs): go vet ok, go test 23 packages ok, make e2e ok (337 s).
Locally after them: internal/web/view ok.
Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>
Seen by the owner on the test server, on real data (2026-10-10).
- Overview's Processes card said "7 of 7 running" with six programs
running and postfix-reload idle. The card counts the programs that
are meant to stay up; a one-shot helper (health.Process.OneShot) is
left out of both numbers and named only when it is in trouble.
- The Milter sockets card clipped its second line ("OpenDKIM,
send-log,...") once the spam filter was the third socket. The line
names the sockets that do not answer when some do not; with all
answering it is their names, or "incl. the spam filter" - the
mockup's words - when the filter is among them.
- A real 2048-bit DKIM value did not fit the three rows of its field
and scrolled inside it. The field is as tall as the value needs
(3 to 12 rows).
The fixtures had a shortened key, two sockets and no one-shot program,
so none of this showed in the evidence screenshots.
go test -count=1 ./internal/health/... ./internal/web/...: ok
Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>
A bounce could be recorded as a successful delivery. The log-tailer's
Fixed:
- A bounce could be recorded as a successful delivery. The log-tailer's
- Log-tailer resumes where it stopped instead of jumping to end-of-file on
- Level-2 rate limit no longer overshoots under concurrency: messages that
Changed:
- The project has a single public home: `github.com/mixeme/selfpost`. Codeberg
- Code comments no longer cite the archived specification. References like
- `docs/code-review.md` is gone. Its plan is finished — phases 0 (bar the
- `docs/architecture.md` gained a *Code layers* section: a diagram of
- Phase 1 doc/code hygiene (`docs/code-review.md`): removed ~30 stale
… (1 more in CHANGELOG)
Security:
- Pre-release security review (plan § D, model Fable, 2026-08-06): full pass
- `saslpasswd2` argv: the application login is now passed after a `--`
Added:
- Optional password encryption for the two secret-bearing downloads (plan
- Domain import accepts an encrypted export: the envelope is detected by its
- `selfpost-backup` writes encrypted archives and reads them back:
- `TestParseDelivery` covers the exotic mail.log shapes the review asked for
- docs: README *Encrypting a backup or export*; `docs/security.md` §
… (14 more in CHANGELOG)
Removed:
- docs: `security.md` — accepted risk «restore old backup revives session rows»
Changed:
- docs: `implementation-plan.md` trimmed to the sole open v1.x gate — pre-release
- docs: `architecture.md` — sessions (SQLite, idle renew, password change),
- docs: `development.md` — expanded e2e stack and `release.yml` matrix workflow.
- docs: `security.md` — accepted risk for send-log rows stuck at `queued` after
- docs: `roadmap.md` — optional send-log / `mail.log` follow-ups under v1.x tail.
… (10 more in CHANGELOG)
Full detail: CHANGELOG.md (0.5.0).
Initial feature-complete implementation of the v1.0 specification (phases 0-11 of `docs/implementation-plan.md`).
Added:
- Panel (Go, single static binary) with SQLite persistence, one-time
- Domain management with per-domain DKIM (RSA-2048, generated in pure Go) and
- Application (sender identity) management: SASL credentials via `sasldb2`,
- Full Postfix relay config generated from env at container start: SMTPS 465,
- Journal milter (pure Go, `go-milter`) recording every send to `send_log`;
… (6 more in CHANGELOG)
Full detail: CHANGELOG.md (0.1.0).
mixandClaude Opus 5.5