audit 2c: findings of the two reviews

Technical review (Opus, 11 findings, 2 medium) and security review (Fable,
no high or medium) of 3c86280..HEAD. Both confirm the port gives
dkim_mail_parse()'s result on every input it parses, and that no line the
check passes is signed with another domain's key.

- F1 (medium): OpenDKIM's parser takes lines no mail program reads as one
  address - "ceo@bank.com:me@mine.com", "Name <ceo@bank.com:me@mine.com>",
  "<b@evil.com, a@mine.com>", "ceo@bank.com <me@mine.com>",
  "ceo@bank.com@mine.com" - and signs for the last while a lenient reader
  shows the first. The line must now also be one address in RFC 5322's
  grammar (net/mail, display names in any charset passed through), at the
  domain OpenDKIM signs for. A quoted display name may still hold anything.
- F2 (medium): the bindings were asked about OpenDKIM's form of the
  address, quotes and all, so "x"@mine.com passed for an application
  holding @mine.com while x@mine.com belonged to another. They are now
  asked about the reader's address, its local part unquoted, as Postfix
  holds the envelope's.
- F3 / security (low): Bindings.Allowed and DomainOf fold case in ASCII
  only: Postfix folds as Unicode (casefold.c, ICU), but every key and
  login the panel writes is ASCII, and the Unicode fold let the Kelvin sign
  pass for "k" (net/mail then refuses such a line on the domain test).
- F4 (low): a TERM between "postfix start-fg &" and "child=$!" is no longer
  lost: the wrapper stops Postfix as soon as the pid is known.
- F5 (low): for startsecs after a start any failed reload passed as "not
  running". postfix-reload is now build/postfix-reload.sh: exit 75 when
  master -t says no master runs, else exec postfix reload; RunOnce returns
  EndError with the status, and only 75 is taken as done. supervisor.State
  goes.
- F6 (low): crashexit spares postfix-reload too - a reload that could not
  be spawned is reported to whoever asked, not a reason to stop the
  container.
- F7 (low): a certs/ that is itself a link is resolved before the walk
  (filepath.WalkDir does not follow its root).
- F8 (low): at shutdown the tailer reads what is left of the rotated
  file before saving its place. Not changed: a refusal line still waiting
  on the old file at shutdown is not kept - the panel writes refused rows
  itself, only a kill loses one, and that window is the minute's grace.
- F9 (low): pct read as text - empty or unreadable is 100, the rest held
  to 0..100.
- F10 (low): the directory is synced after sasldb2's rename.
- F11 (low): POSTFIX_STARTSECS by expr, so "010" or "08" in
  MILTER_WAIT_TIMEOUT are decimal, not octal or an error.
- Security (low): pagehide also empties defaultValue - the input's value
  attribute and the textarea's text - not only .value. A sasldb2.new left
  by a killed panel is removed at start (entrypoint) and never archived.
  security.md says that links under certs/ are followed and by whom they
  can be placed.

Tests: sender check cases for F1 (four lines), F2 (a bound address
quoted, for its owner and for another), F3; EndError's state and status;
pct cases. architecture.md and CHANGELOG describe the reader rule. Stand
(2026-10-15, make e2e, exit 0); go vet and go test ./... pass on the
server (24 packages).

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>

internal/supervisor/rpc.go

@@ -66,16 +66,6 @@ func RunOnce(program string) error {
 	return newRPC(socketPath).runOnce(program)
 }
 
-// State is the state supervisord gives a program, by its name: RUNNING,
-// STARTING, EXITED ... (supervisor 4.2.5, supervisor/states.py).
-func State(program string) (string, error) {
-	v, err := newRPC(socketPath).call("supervisor.getProcessInfo", program)
-	if err != nil {
-		return "", fmt.Errorf("supervisor: state of %s: %w", program, err)
-	}
-	return v.members()["statename"].str(), nil
-}
-
 type rpc struct {
 	client *http.Client
 }
@@ -125,11 +115,25 @@ func (c *rpc) runOnce(program string) error {
 	if info.state == stateExited && info.exitStatus == 0 {
 		return nil
 	}
-	msg := fmt.Sprintf("supervisor: %s ended %s, exit status %d", program, info.stateName, info.exitStatus)
-	if info.spawnErr != "" {
-		msg += ": " + info.spawnErr
+	return &EndError{Program: program, State: info.stateName, Status: info.exitStatus, SpawnErr: info.spawnErr}
+}
+
+// EndError is a run of RunOnce that did not end EXITED with status 0: the
+// state it ended in, its exit status, and supervisord's account of a failed
+// spawn.
+type EndError struct {
+	Program  string
+	State    string
+	Status   int
+	SpawnErr string
+}
+
+func (e *EndError) Error() string {
+	msg := fmt.Sprintf("supervisor: %s ended %s, exit status %d", e.Program, e.State, e.Status)
+	if e.SpawnErr != "" {
+		msg += ": " + e.SpawnErr
 	}
-	return errors.New(msg)
+	return msg
 }
 
 // processInfo is the part of getProcessInfo's struct RunOnce reads.