inbound-upstream-result: the upstream's answer in the Inbound log

The owner, 2026-10-16: the Inbound log lacks the upstream's answer - "Не
понятна судьба письма: принято, отклонено, хост не доступен"; the result
in the row only, a page per message later if needed. Mockups 5348330 and
46b90d2, plan 295d72e.

- Migration 0012: inbound_spam_log gains queue_id, upstream_status ('',
  queued, held, sent, deferred, bounced; CHECK), upstream_relay,
  upstream_reply, upstream_at, and a partial index on queue_id. Schema 12.
- The inbound journal milter writes an accepted row with the queue id of
  end-of-message and "queued" ("held" when the filter had it held), the
  recipient as Postfix logs it (recipientAsLogged), after detaching older
  rows of a queue id Postfix uses again; no queue id, no result.
- The tailer: a delivery line no send-log row took goes to the journal -
  status, relay= ("" for none), the reply after the first status=, cut to
  255 printable bytes, the line's time; queued/held/deferred rows only,
  sent and bounced final. qmgr's expiry makes them bounced, keeping the
  last reply. cleanup's "removed (" detaches rows of a message never
  queued. Addresses in delivery lines are read by Postfix's quoting
  (loggedAddress): a quoted RCPT TO cannot end one early.
- The page: an Upstream column - a plain tag for queued and held, else a
  tag opening the host, the reply, when and what follows; "—" for refused
  mail and older rows. Help (word for word with the mockup), guide,
  architecture, security, schema-migrations, CHANGELOG.

Reviewed before the commit (technical and security, 2026-10-16); the plan
lists each finding and what it became.

Tests: store (results, finality, expiry, held, a reused id, the queue-id
index in every plan), milter (queue id, held, quoted recipient, no {i}),
logtail (relay and reply, a forged quoted recipient, Run hands the journal
what the send log did not take, cleanup's removal), view (the column, held,
null sender), e2e (both relayed messages sent with the sink's 250; an
upstream refusing connections deferred with the reason and no host, then
expired to bounced; the refused row has none). go vet + go test (26
packages) and make e2e on the test server for this tree.

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

internal/logtail/inbound.go

@@ -11,13 +11,47 @@ import (
 )
 
 // InboundStore is what the tailer needs of the inbound antispam journal:
-// writing the rows for refused mail, knowing which domains are inbound, and
-// pruning. *store.Store satisfies it.
+// writing the rows for refused mail, knowing which domains are inbound,
+// putting the upstream's answers on the rows of accepted mail, and pruning.
+// *store.Store satisfies it.
 type InboundStore interface {
 	InsertInboundSpam(e store.InboundSpamEntry) error
 	InsertInboundSpamOnce(e store.InboundSpamEntry) (bool, error)
 	IsInboundDomain(name string) (bool, error)
 	PruneInboundSpam(cutoff time.Time, keep int) (int64, error)
+	UpdateInboundUpstream(queueID, recipient, status, relay, reply string, at time.Time) (int64, error)
+	ExpireInboundUpstream(queueID string, at time.Time) (int64, error)
+	ForgetInboundQueueID(queueID string) error
+}
+
+// upstream puts a delivery line's result on the journal rows of a message
+// accepted on port 25 (inbound-upstream-result). The tailer offers it every
+// delivery line no send-log row took: the rows of that queue id and recipient
+// take it, and a line of any other mail - the panel's own, a bounce Postfix
+// sends back to a stranger - matches none. relay "none" is a line written
+// without a session (Postfix 3.10.13, src/smtp/smtp_trouble.c:273, 421: the
+// host is then only in the reply), kept as "". The reply is the upstream's
+// text, or Postfix's own about a host it could not reach, cut and made
+// printable like a refusal's reason. One update per attempt, never a row of
+// its own: the journal's caps stand.
+func (j *inboundJournal) upstream(line string, now time.Time, queueID, recipient, status string) {
+	at, rest := lineTime(line, now)
+	relay, reply := deliveryReply(rest)
+	if relay == "none" {
+		relay = ""
+	}
+	if _, err := j.st.UpdateInboundUpstream(queueID, recipient, status, printable(relay, inboundDetailMax),
+		printable(reply, store.UpstreamReplyMax), at); err != nil {
+		log.Printf("log-tailer: inbound journal: upstream %s/%s -> %s: %v", queueID, recipient, status, err)
+	}
+}
+
+// expired makes the rows of a port-25 message Postfix gave up on bounced.
+func (j *inboundJournal) expired(line string, now time.Time, queueID string) {
+	at, _ := lineTime(line, now)
+	if _, err := j.st.ExpireInboundUpstream(queueID, at); err != nil {
+		log.Printf("log-tailer: inbound journal: expire %s: %v", queueID, err)
+	}
 }
 
 // Inbound turns on the inbound half of the tailer: journal rows for mail that
@@ -153,6 +187,13 @@ func (j *inboundJournal) handle(line string, now time.Time, catchingUp bool) {
 	}
 	if m := inboundForgetRe.FindStringSubmatch(rest); m != nil {
 		delete(j.port25, m[1]+m[2]+m[3])
+		// A queue file cleanup removed was never queued: rows the milter wrote
+		// for it will get no delivery line (store.ForgetInboundQueueID).
+		if m[3] != "" {
+			if err := j.st.ForgetInboundQueueID(m[3]); err != nil {
+				log.Printf("log-tailer: inbound journal: forget %s: %v", m[3], err)
+			}
+		}
 		return
 	}
 	m := inboundRejectRe.FindStringSubmatch(rest)

internal/logtail/inbound_test.go

@@ -4,6 +4,7 @@ import (
 	"context"
 	"errors"
 	"strings"
+	"sync"
 	"testing"
 	"time"
 
@@ -15,6 +16,39 @@ type fakeInboundStore struct {
 	rows      []store.InboundSpamEntry
 	lookupErr error
 	pruned    []int
+
+	// upstream records the results put on rows, as
+	// "queue-id|recipient|status|relay|reply|time" or "queue-id|expired|time";
+	// Run writes it from its own goroutine.
+	mu       sync.Mutex
+	upstream []string
+}
+
+func (f *fakeInboundStore) UpdateInboundUpstream(queueID, recipient, status, relay, reply string, at time.Time) (int64, error) {
+	f.mu.Lock()
+	defer f.mu.Unlock()
+	f.upstream = append(f.upstream, strings.Join([]string{queueID, recipient, status, relay, reply, at.Format(time.RFC3339)}, "|"))
+	return 1, nil
+}
+
+func (f *fakeInboundStore) ExpireInboundUpstream(queueID string, at time.Time) (int64, error) {
+	f.mu.Lock()
+	defer f.mu.Unlock()
+	f.upstream = append(f.upstream, queueID+"|expired|"+at.Format(time.RFC3339))
+	return 1, nil
+}
+
+func (f *fakeInboundStore) ForgetInboundQueueID(queueID string) error {
+	f.mu.Lock()
+	defer f.mu.Unlock()
+	f.upstream = append(f.upstream, queueID+"|forgot")
+	return nil
+}
+
+func (f *fakeInboundStore) upstreamCalls() []string {
+	f.mu.Lock()
+	defer f.mu.Unlock()
+	return append([]string(nil), f.upstream...)
 }
 
 func (f *fakeInboundStore) InsertInboundSpam(e store.InboundSpamEntry) error {

internal/logtail/logtail.go

@@ -85,8 +85,8 @@ const (
 // calls it on every prune cycle so a panel change takes effect without restart.
 type RetentionDays func() int
 
-// deliveryRe matches a Postfix delivery line and captures queue-id, recipient
-// and status, e.g.
+// deliveryRe matches a Postfix delivery line and captures queue-id, recipient,
+// orig_to, relay and status, e.g.
 //
 //	postfix/smtp[26]: 41E862C00D9E: to=<a@example.net>, relay=…, dsn=2.0.0, status=sent (250 OK)
 //
@@ -116,7 +116,19 @@ type RetentionDays func() int
 // controls. A bounce whose reply quoted "status=sent" would then be filed as a
 // success. The real field is always the first one after to=<…>: in
 // log_adhoc() the reply is the "(%s)" after status=.
-var deliveryRe = regexp.MustCompile(`^\S+ [^\s\[]+\[\d+\]: ([0-9A-Za-z]+): to=<(.*?)>, (?:orig_to=<(.*?)>, )?relay=.*?\bstatus=(\w+)`)
+var deliveryRe = regexp.MustCompile(`^\S+ [^\s\[]+\[\d+\]: ([0-9A-Za-z]+): to=<(` + loggedAddress + `)>, (?:orig_to=<(` + loggedAddress + `)>, )?relay=([^,\s]*).*?\bstatus=(\w+)`)
+
+// loggedAddress is an address as Postfix logs it, external form: a local part
+// in quotes when it is not a plain dot-string - and then it may hold "<", ">",
+// "," and "=", with only '"' and '\' escaped - or one with none of '"' and
+// '>' (Postfix 3.10.13, src/global/quote_822_local.c,
+// src/global/info_log_addr_form.c). Read by that grammar, a stranger's quoted
+// RCPT TO cannot end the address early and pass "orig_to=<…>, relay=…,
+// status=…" of his own as the line's fields (security review of
+// inbound-upstream-result, 2026-10-16; a local part with "@" is a routed
+// address, which port 25 refuses as relaying anyway: src/trivial-rewrite/
+// resolve.c:467, src/smtpd/smtpd_check.c:1724, allow_untrusted_routing=no).
+const loggedAddress = `"(?:[^"\\]|\\.)*"@[^>]*|[^>"]*`
 
 // parseDelivery extracts (queue-id, recipient, status) from a mail.log line.
 // ok is false for lines that are not recognised delivery results. The
@@ -133,7 +145,7 @@ func parseDelivery(line string) (queueID, recipient, status string, ok bool) {
 	if m[3] != "" {
 		recipient = m[3]
 	}
-	switch m[4] {
+	switch m[5] {
 	case "sent":
 		status = store.StatusSent
 	case "deferred":
@@ -146,6 +158,25 @@ func parseDelivery(line string) (queueID, recipient, status string, ok bool) {
 	return m[1], recipient, status, true
 }
 
+// deliveryReply returns the host and the reply of a delivery line (the line
+// after its time stamp): relay= - which log_adhoc() writes right after to=
+// and orig_to=, followed by a comma - and the "(%s)" after the first status=,
+// to the end of the line (Postfix 3.10.13, src/global/log_adhoc.c). Taking the
+// first status= keeps the reply whole when the far end's text holds one of
+// its own. A line that is not a delivery line gives "", "".
+func deliveryReply(rest string) (relay, reply string) {
+	loc := deliveryRe.FindStringSubmatchIndex(rest)
+	if loc == nil {
+		return "", ""
+	}
+	relay = rest[loc[8]:loc[9]]
+	tail := strings.TrimSpace(rest[loc[1]:])
+	if strings.HasPrefix(tail, "(") && strings.HasSuffix(tail, ")") {
+		reply = tail[1 : len(tail)-1]
+	}
+	return relay, reply
+}
+
 // expiryRe matches qmgr's line for a message it gave up on:
 //
 //	postfix/qmgr[93]: 41E862C00D9E: from=<app@example.org>, status=expired, returned to sender
@@ -225,18 +256,28 @@ func Run(ctx context.Context, path string, st StatusStore, retention RetentionDa
 		}
 		keeper.add(line, now, catchingUp)
 		refusals.handle(line, now, Place{FP: tr.line.FP, End: tr.lineStart})
+		// A delivery or expiry line no send-log row takes may be of mail
+		// accepted on port 25: the inbound journal's rows take its result.
 		queueID, recipient, status, ok := parseDelivery(line)
 		if !ok {
 			if queueID, ok := parseExpiry(line); ok {
-				if _, err := st.ExpireMessage(queueID); err != nil {
+				n, err := st.ExpireMessage(queueID)
+				if err != nil {
 					log.Printf("log-tailer: expire %s: %v", queueID, err)
 				}
+				if n == 0 && journal != nil {
+					journal.expired(line, now, queueID)
+				}
 			}
 			return
 		}
-		if _, err := st.UpdateStatus(queueID, recipient, status); err != nil {
+		n, err := st.UpdateStatus(queueID, recipient, status)
+		if err != nil {
 			log.Printf("log-tailer: update %s/%s -> %s: %v", queueID, recipient, status, err)
 		}
+		if n == 0 && journal != nil {
+			journal.upstream(line, now, queueID, recipient, status)
+		}
 	})
 }
 

internal/logtail/logtail_test.go

@@ -339,6 +339,9 @@ func (c *captureStore) UpdateStatus(queueID, recipient, status string) (int64, e
 	c.mu.Lock()
 	defer c.mu.Unlock()
 	c.calls = append(c.calls, queueID+"|"+recipient+"|"+status)
+	if strings.HasPrefix(queueID, "P25") {
+		return 0, nil // mail accepted on port 25: no send-log row
+	}
 	return 1, nil
 }
 
@@ -347,6 +350,9 @@ func (c *captureStore) ExpireMessage(queueID string) (int64, error) {
 	c.mu.Lock()
 	defer c.mu.Unlock()
 	c.calls = append(c.calls, queueID+"|*|expired")
+	if strings.HasPrefix(queueID, "P25") {
+		return 0, nil
+	}
 	return 1, nil
 }
 

internal/logtail/upstream_test.go

@@ -0,0 +1,121 @@
+package logtail
+
+import (
+	"context"
+	"os"
+	"path/filepath"
+	"strings"
+	"testing"
+	"time"
+)
+
+// The host and the reply of a delivery line, as log_adhoc() writes them: the
+// relay= right after to=, the "(...)" after the first status= to the end of
+// the line - also when the far end's reply holds a status= of its own.
+func TestDeliveryReply(t *testing.T) {
+	for _, c := range []struct{ line, relay, reply string }{
+		{"selfpost postfix/smtp[315]: 82922153D147: to=<carrel@dev.mixdep.ru>, relay=mc-ent.mixfed.ru[188.242.125.61]:25, delay=498, delays=491/0.03/2.5/5, dsn=2.0.0, status=sent (250 2.0.0 Ok: queued as CE05D10261D)",
+			"mc-ent.mixfed.ru[188.242.125.61]:25", "250 2.0.0 Ok: queued as CE05D10261D"},
+		{"selfpost postfix/smtp[300]: D6E4F153D147: to=<a@in.example.com>, relay=none, delay=30, delays=0.1/0/30/0, dsn=4.4.1, status=deferred (connect to mx.up.example[198.51.100.5]:25: Connection refused)",
+			"none", "connect to mx.up.example[198.51.100.5]:25: Connection refused"},
+		{"selfpost postfix/smtp[312]: 1CACF153D147: to=<a@in.example.com>, orig_to=<A@in.example.com>, relay=mx.up.example[198.51.100.5]:25, conn_use=2, delay=1.9, dsn=5.7.1, status=bounced (host mx.up.example[198.51.100.5] said: 550 5.7.1 not status=sent (in reply to end of DATA command))",
+			"mx.up.example[198.51.100.5]:25", "host mx.up.example[198.51.100.5] said: 550 5.7.1 not status=sent (in reply to end of DATA command)"},
+		{"selfpost postfix/qmgr[286]: 1484E1539884: removed", "", ""},
+	} {
+		relay, reply := deliveryReply(c.line)
+		if relay != c.relay || reply != c.reply {
+			t.Errorf("deliveryReply(%q) =\n  %q, %q\nwant\n  %q, %q", c.line, relay, reply, c.relay, c.reply)
+		}
+	}
+}
+
+// The journal takes a delivery line's result with the host ("" for relay=none),
+// the reply made printable and cut, and the line's own time.
+func TestInboundJournalTakesTheUpstreamsAnswer(t *testing.T) {
+	j, st := inboundFixture()
+	now := time.Date(2026, 10, 16, 12, 0, 0, 0, time.UTC)
+	j.upstream("Oct 16 10:16:42 selfpost postfix/smtp[300]: P25A: to=<a@in.example.com>, relay=none, delay=30, dsn=4.4.1, status=deferred (connect to mx.up.example[198.51.100.5]:25: Connection refused\x01"+strings.Repeat("x", 300)+")",
+		now, "P25A", "a@in.example.com", "deferred")
+	calls := st.upstreamCalls()
+	if len(calls) != 1 {
+		t.Fatalf("calls = %q", calls)
+	}
+	f := strings.Split(calls[0], "|")
+	if f[0] != "P25A" || f[1] != "a@in.example.com" || f[2] != "deferred" || f[3] != "" {
+		t.Errorf("call = %q", calls[0])
+	}
+	if !strings.HasPrefix(f[4], "connect to mx.up.example[198.51.100.5]:25: Connection refused") || len(f[4]) > 255 || strings.ContainsRune(f[4], 1) {
+		t.Errorf("reply = %q (%d bytes)", f[4], len(f[4]))
+	}
+	if at, _ := time.Parse(time.RFC3339, f[5]); !at.Equal(time.Date(2026, 10, 16, 10, 16, 42, 0, time.Local).UTC()) {
+		t.Errorf("at = %s, want the line's time", f[5])
+	}
+}
+
+// Run hands the journal what no send-log row took: a delivery line and an
+// expiry line of a port-25 message (captureStore takes no queue id with
+// "P25"), and nothing of the mail the send log knows.
+func TestRunPutsTheUpstreamsAnswerOnTheJournal(t *testing.T) {
+	old := pollInterval
+	pollInterval = 10 * time.Millisecond
+	t.Cleanup(func() { pollInterval = old })
+
+	path := filepath.Join(t.TempDir(), "mail.log")
+	if err := os.WriteFile(path, nil, 0o644); err != nil {
+		t.Fatal(err)
+	}
+	cs := &captureStore{}
+	_, in := inboundFixture()
+	ctx, cancel := context.WithCancel(context.Background())
+	done := make(chan error, 1)
+	go func() {
+		done <- Run(ctx, path, cs, func() int { return 90 }, &Inbound{Store: in, Retention: func() int { return 90 }}, nil)
+	}()
+	time.Sleep(50 * time.Millisecond)
+	appendLine(t, path, "host postfix/smtp[1]: Q1: to=<a@example.net>, relay=x, dsn=2.0.0, status=sent (ok)")
+	appendLine(t, path, "host postfix/smtp[2]: P25A: to=<a@in.example.com>, relay=mx.up.example[198.51.100.5]:25, dsn=2.0.0, status=sent (250 2.0.0 Ok)")
+	appendLine(t, path, "host postfix/qmgr[3]: P25B: from=<s@example.net>, status=expired, returned to sender")
+	waitFor(t, func() bool { return len(in.upstreamCalls()) == 2 })
+	calls := in.upstreamCalls()
+	if !strings.HasPrefix(calls[0], "P25A|a@in.example.com|sent|mx.up.example[198.51.100.5]:25|250 2.0.0 Ok|") ||
+		!strings.HasPrefix(calls[1], "P25B|expired|") {
+		t.Errorf("journal calls = %q", calls)
+	}
+	cancel()
+	select {
+	case <-done:
+	case <-time.After(2 * time.Second):
+		t.Fatal("Run did not return after cancel")
+	}
+	for _, c := range in.upstreamCalls() {
+		if strings.HasPrefix(c, "Q1|") {
+			t.Errorf("the journal was offered outbound mail: %q", c)
+		}
+	}
+}
+
+// A stranger's quoted RCPT TO may hold ">", "," and "=": read by Postfix's
+// quoting, the address is his whole local part, and the line's own fields -
+// the relay and status after it - are the ones taken, not those he wrote.
+func TestDeliveryLineReadsAQuotedRecipientWhole(t *testing.T) {
+	line := `Oct 16 10:16:42 selfpost postfix/smtp[300]: P25F: to=<"a>, orig_to=<b@in.example.com>, relay=F, dsn=5.0.0, status=bounced (FORGED"@in.example.com>, relay=mx.up.example[198.51.100.5]:25, delay=1, dsn=2.0.0, status=sent (250 2.0.0 Ok)`
+	q, r, s, ok := parseDelivery(line)
+	if !ok || q != "P25F" || s != "sent" || r != `"a>, orig_to=<b@in.example.com>, relay=F, dsn=5.0.0, status=bounced (FORGED"@in.example.com` {
+		t.Errorf("parseDelivery = %q %q %q %v", q, r, s, ok)
+	}
+	_, rest := SplitTimestamp(line)
+	if relay, reply := deliveryReply(rest); relay != "mx.up.example[198.51.100.5]:25" || reply != "250 2.0.0 Ok" {
+		t.Errorf("deliveryReply = %q, %q", relay, reply)
+	}
+}
+
+// cleanup's "removed (" is a queue file that was never queued: the rows the
+// milter wrote for it are detached from its queue id.
+func TestInboundJournalForgetsAMessageCleanupRemoved(t *testing.T) {
+	j, st := inboundFixture()
+	j.handle("Oct 16 10:16:42 selfpost postfix/cleanup[52]: 4A1B2C3D: removed (canceled)", tailNow, false)
+	j.handle("Oct 16 10:16:42 selfpost postfix/qmgr[52]: 5A1B2C3D: removed", tailNow, false)
+	if calls := st.upstreamCalls(); len(calls) != 1 || calls[0] != "4A1B2C3D|forgot" {
+		t.Errorf("calls = %q", calls)
+	}
+}

internal/milter/inbound.go

@@ -23,6 +23,7 @@ import (
 type InboundStore interface {
 	InsertInboundSpam(e store.InboundSpamEntry) error
 	IsInboundDomain(name string) (bool, error)
+	ForgetInboundQueueID(queueID string) error
 }
 
 // inboundSession is the inbound journal milter: the last milter on port 25,
@@ -79,8 +80,11 @@ func (s *inboundSession) MailFrom(from string, m *milter.Modifier) (milter.Respo
 	return milter.RespContinue, nil
 }
 
+// RcptTo keeps the recipient as Postfix logs it, so that the delivery lines
+// that carry the upstream's answer find the row (recipientAsLogged): a quoted
+// local part that needs no quotes is written without them.
 func (s *inboundSession) RcptTo(rcpt string, m *milter.Modifier) (milter.Response, error) {
-	s.rcpts = append(s.rcpts, cleanAddress(rcpt))
+	s.rcpts = append(s.rcpts, recipientAsLogged(rcpt))
 	return milter.RespContinue, nil
 }
 
@@ -156,11 +160,13 @@ func (s *inboundSession) signed(queueID string) bool {
 // rest as session.Body in milter.go.
 func (s *inboundSession) Body(m *milter.Modifier) (milter.Response, error) {
 	// The queue id is known only now, and with it whether the verdict headers
-	// read on the way here are the filter's.
-	if !s.signed(macro(m, "i")) {
+	// read on the way here are the filter's. The rows keep it: the delivery
+	// lines that put the upstream's answer on them name it (logtail).
+	queueID := macro(m, "i")
+	if !s.signed(queueID) {
 		s.seen = false
 	}
-	s.record()
+	s.record(queueID)
 	s.reset()
 	return milter.RespContinue, nil
 }
@@ -175,10 +181,17 @@ func (s *inboundSession) reset() {
 	s.action, s.result, s.seen, s.sig = "", "", false, ""
 }
 
-// record writes one row per recipient at an inbound domain. Other recipients
-// of port 25 (a DMARC report address at the server's own name) are not the
-// relay's mail and get no row. Failures are logged, never propagated.
-func (s *inboundSession) record() {
+// record writes one row per recipient at an inbound domain, with the queue id
+// of the message and "queued" - "held" when the filter's verdict had Postfix
+// hold it (src/cleanup/cleanup_milter.c: a milter's HOLD puts the message in
+// the hold queue, which qmgr does not schedule). The message is about to be
+// queued for its upstream, and the rows are written before Postfix goes on,
+// so before any delivery line of it; older rows of a queue id Postfix uses
+// again are detached first. With no queue id (none came) the rows have no
+// result: nothing could report one. Other recipients of port 25 (a DMARC
+// report address at the server's own name) are not the relay's mail and get
+// no row. Failures are logged, never propagated.
+func (s *inboundSession) record(queueID string) {
 	e := store.InboundSpamEntry{
 		ClientIP: s.clientIP,
 		From:     s.from,
@@ -193,6 +206,15 @@ func (s *inboundSession) record() {
 			e.Decision = store.SpamDecisionQuarantine
 		}
 	}
+	if queueID != "" {
+		e.QueueID, e.Upstream = queueID, store.UpstreamQueued
+		if e.Decision == store.SpamDecisionQuarantine {
+			e.Upstream = store.UpstreamHeld
+		}
+		if err := s.rec.ForgetInboundQueueID(queueID); err != nil {
+			log.Printf("inbound-journal: detach older rows of %s: %v", queueID, err)
+		}
+	}
 	for _, to := range s.rcpts {
 		domain := domainOf(to)
 		ok, err := s.rec.IsInboundDomain(domain)

internal/milter/inbound_test.go

@@ -17,6 +17,7 @@ type fakeInbound struct {
 	rows      []store.InboundSpamEntry
 	insertErr error
 	lookupErr error
+	forgot    []string
 }
 
 func (f *fakeInbound) InsertInboundSpam(e store.InboundSpamEntry) error {
@@ -27,6 +28,11 @@ func (f *fakeInbound) InsertInboundSpam(e store.InboundSpamEntry) error {
 	return nil
 }
 
+func (f *fakeInbound) ForgetInboundQueueID(queueID string) error {
+	f.forgot = append(f.forgot, queueID)
+	return nil
+}
+
 func (f *fakeInbound) IsInboundDomain(name string) (bool, error) {
 	if f.lookupErr != nil {
 		return false, f.lookupErr
@@ -100,6 +106,8 @@ func TestInboundRecordsAcceptedMessage(t *testing.T) {
 		InboundDomain: "in.example.com", ClientIP: "203.0.113.7",
 		From: "sender@example.net", To: "a@in.example.com", Subject: "Schön",
 		Decision: store.SpamDecisionAccept, Engine: store.SpamEngineSelfPost,
+		// The queue id of end-of-message, for the delivery lines to come.
+		QueueID: "ABC123", Upstream: store.UpstreamQueued,
 	}
 	if rec.rows[0] != want {
 		t.Errorf("row = %+v\nwant  %+v", rec.rows[0], want)
@@ -204,6 +212,7 @@ func TestInboundResetsBetweenMessages(t *testing.T) {
 		InboundDomain: "in.example.com", ClientIP: "203.0.113.7",
 		From: "two@example.net", To: "b@in.example.com",
 		Decision: store.SpamDecisionAccept, Engine: store.SpamEngineSelfPost,
+		QueueID: "ABC123", Upstream: store.UpstreamQueued,
 	}
 	if rec.rows[1] != want {
 		t.Errorf("second row = %+v\nwant         %+v", rec.rows[1], want)
@@ -354,3 +363,40 @@ func TestFilterSignatureIsWhatTheFilterWrites(t *testing.T) {
 		t.Errorf("FilterSignature = %s", got)
 	}
 }
+
+// The row is the delivery lines' to find: a recipient is kept as Postfix logs
+// it, a held message starts held, older rows of a reused queue id are
+// detached first - once per message - and a message with no queue id has no
+// result, since nothing could ever report one.
+func TestInboundRowsMeetTheirDeliveryLines(t *testing.T) {
+	rec := &fakeInbound{domains: map[string]bool{"in.example.com": true}}
+	s := inboundSessionFor(t, rec, true)
+	message(t, s, "sender@example.net", []string{`<"owner"@in.example.com>`, "b@in.example.com"}, nil)
+	if len(rec.rows) != 2 || rec.rows[0].To != "owner@in.example.com" {
+		t.Fatalf("rows = %+v, want the quoted recipient as logged", rec.rows)
+	}
+	if len(rec.forgot) != 1 || rec.forgot[0] != "ABC123" {
+		t.Errorf("detached %q, want ABC123 once", rec.forgot)
+	}
+
+	rec.rows = nil
+	message(t, s, "sender@example.net", []string{"a@in.example.com"},
+		[][2]string{{"X-Rspamd-Action", "quarantine"}, testSig})
+	if len(rec.rows) != 1 || rec.rows[0].Upstream != store.UpstreamHeld {
+		t.Errorf("a held message's row = %+v, want held", rec.rows)
+	}
+
+	rec.rows, rec.forgot = nil, nil
+	if _, err := s.MailFrom("sender@example.net", mods(nil)); err != nil {
+		t.Fatal(err)
+	}
+	if _, err := s.RcptTo("a@in.example.com", mods(nil)); err != nil {
+		t.Fatal(err)
+	}
+	if _, err := s.Body(mods(nil)); err != nil {
+		t.Fatal(err)
+	}
+	if len(rec.rows) != 1 || rec.rows[0].QueueID != "" || rec.rows[0].Upstream != "" || len(rec.forgot) != 0 {
+		t.Errorf("with no queue id: rows %+v, detached %q", rec.rows, rec.forgot)
+	}
+}

internal/store/inboundspam.go

@@ -25,6 +25,18 @@ const (
 	SpamEngineSelfPost = "selfpost" // nobody: relayed with no filter attached
 )
 
+// What the upstream made of a message accepted on port 25, on its journal
+// rows (migration 0012). Kept in sync with the CHECK constraint of
+// inbound_spam_log; "" is a row with no result (refused mail, or written
+// before 2.10.0). sent and bounced are final.
+const (
+	UpstreamQueued   = "queued"   // accepted, not tried yet
+	UpstreamHeld     = "held"     // accepted into the hold queue by the filter's verdict, not tried until released
+	UpstreamSent     = "sent"     // the upstream took it
+	UpstreamDeferred = "deferred" // put off or not reached; Postfix tries again
+	UpstreamBounced  = "bounced"  // refused for good, or expired in the queue
+)
+
 // InboundSpamEntry is one row of the inbound antispam journal: what happened
 // to a message offered on port 25 for one recipient. Metadata only - the
 // message itself is relayed, not stored. Subject and Detail may be empty.
@@ -37,6 +49,11 @@ type InboundSpamEntry struct {
 	Decision      string
 	Engine        string
 	Detail        string
+	// QueueID and Upstream are set on mail that was accepted: the queue id
+	// the delivery lines will name, and UpstreamQueued (UpstreamHeld for a
+	// message the filter had held).
+	QueueID  string
+	Upstream string
 	// At is when it happened; zero means now. The log tailer dates a refusal
 	// by its mail.log line, which it may read long after.
 	At time.Time
@@ -56,10 +73,11 @@ func (s *Store) InsertInboundSpam(e InboundSpamEntry) error {
 	}
 	_, err := s.db.Exec(
 		`INSERT INTO inbound_spam_log
-			(inbound_domain, client_ip, from_addr, to_addr, subject, decision, engine, detail, created_at, inbound_domain_id)
-		 VALUES (?, ?, ?, ?, ?, ?, ?, ?, ?, `+inboundDomainID+`)`,
+			(inbound_domain, client_ip, from_addr, to_addr, subject, decision, engine, detail, created_at, inbound_domain_id,
+			 queue_id, upstream_status)
+		 VALUES (?, ?, ?, ?, ?, ?, ?, ?, ?, `+inboundDomainID+`, ?, ?)`,
 		e.InboundDomain, e.ClientIP, e.From, e.To, e.Subject, e.Decision, e.Engine, e.Detail,
-		at.UTC().Format(time.RFC3339), e.InboundDomain,
+		at.UTC().Format(time.RFC3339), e.InboundDomain, e.QueueID, e.Upstream,
 	)
 	if err != nil {
 		return fmt.Errorf("insert inbound_spam_log: %w", err)
@@ -94,6 +112,74 @@ func (s *Store) InsertInboundSpamOnce(e InboundSpamEntry) (bool, error) {
 	return n > 0, nil
 }
 
+// updateUpstreamQuery puts one delivery attempt's result on the rows of a
+// queue id and recipient whose result is not final; expireUpstreamQuery makes
+// those of a queue id bounced, saying it expired after the last reply. Both
+// read the queue id through idx_inbound_spam_log_queue_id
+// (TestInboundUpstreamUsesItsIndex).
+const (
+	updateUpstreamQuery = `UPDATE inbound_spam_log
+		SET upstream_status = ?, upstream_relay = ?, upstream_reply = ?, upstream_at = ?
+		WHERE queue_id = ? AND queue_id <> '' AND to_addr = ? COLLATE NOCASE
+		  AND upstream_status IN ('queued', 'held', 'deferred')`
+	expireUpstreamQuery = `UPDATE inbound_spam_log
+		SET upstream_status = 'bounced', upstream_at = ?,
+		    upstream_reply = substr(CASE WHEN upstream_reply = '' THEN 'expired in the queue'
+		                                 ELSE 'expired in the queue; last reply: ' || upstream_reply END, 1, ?)
+		WHERE queue_id = ? AND queue_id <> '' AND upstream_status IN ('queued', 'held', 'deferred')`
+	forgetQueueIDQuery = `UPDATE inbound_spam_log
+		SET queue_id = '',
+		    upstream_status = CASE WHEN upstream_status IN ('queued', 'held', 'deferred') THEN '' ELSE upstream_status END
+		WHERE queue_id = ? AND queue_id <> ''`
+)
+
+// ForgetInboundQueueID detaches the journal rows of a queue id from it: those
+// still open lose their result too, as nothing will ever report it. The
+// milter calls it before it writes a new message's rows - Postfix reuses
+// queue ids (enable_long_queue_ids=no, the default: microseconds and the
+// queue file's inode, src/global/mail_queue.h), and only one live queue file
+// has an id, so older rows of it are of a message that is gone and must not
+// take the new one's results. The tailer calls it when cleanup removes a
+// queue file it did not queue ("removed (canceled)"): the milter had written
+// the rows, but the message was never queued.
+func (s *Store) ForgetInboundQueueID(queueID string) error {
+	if _, err := s.db.Exec(forgetQueueIDQuery, queueID); err != nil {
+		return fmt.Errorf("forget inbound queue id %s: %w", queueID, err)
+	}
+	return nil
+}
+
+// UpstreamReplyMax is how much of an upstream's reply a row keeps.
+const UpstreamReplyMax = 255
+
+// UpdateInboundUpstream puts the result of one attempt to hand a message to
+// its upstream on its journal rows - those of queueID and recipient (case
+// folded, as Postfix logs the address it was given) - unless they hold a
+// final one already: a line read twice after a restart, or an older one read
+// after a newer, does not undo a sent. relay is the host that answered, ""
+// when there was no session; reply is cut to UpstreamReplyMax by the caller.
+// It returns how many rows took it: 0 for mail that is not port 25's. A
+// message the filter had held takes its results once it is released.
+func (s *Store) UpdateInboundUpstream(queueID, recipient, status, relay, reply string, at time.Time) (int64, error) {
+	res, err := s.db.Exec(updateUpstreamQuery, status, relay, reply, at.UTC().Format(time.RFC3339), queueID, recipient)
+	if err != nil {
+		return 0, fmt.Errorf("update inbound upstream %s: %w", queueID, err)
+	}
+	return res.RowsAffected()
+}
+
+// ExpireInboundUpstream makes the rows of a message Postfix gave up on
+// bounced (qmgr's "status=expired, returned to sender", which names no
+// recipient): the sender was sent a bounce. The last reply stays, after a
+// note that the message expired.
+func (s *Store) ExpireInboundUpstream(queueID string, at time.Time) (int64, error) {
+	res, err := s.db.Exec(expireUpstreamQuery, at.UTC().Format(time.RFC3339), UpstreamReplyMax, queueID)
+	if err != nil {
+		return 0, fmt.Errorf("expire inbound upstream %s: %w", queueID, err)
+	}
+	return res.RowsAffected()
+}
+
 // PruneInboundSpam deletes journal rows older than cutoff and then, if more
 // than keep rows are left, the oldest of those. It returns how many went.
 func (s *Store) PruneInboundSpam(cutoff time.Time, keep int) (int64, error) {
@@ -130,6 +216,12 @@ type InboundSpamRow struct {
 	Engine        string
 	Detail        string
 	CreatedAt     time.Time
+	// The upstream's answer: its status ("" for none), the host that gave
+	// it, the reply and when.
+	Upstream      string
+	UpstreamRelay string
+	UpstreamReply string
+	UpstreamAt    time.Time
 }
 
 // InboundSpamFilter narrows QueryInboundSpam and CountInboundSpam. Like
@@ -166,7 +258,8 @@ func (s *Store) QueryInboundSpam(filter InboundSpamFilter, limit, offset int) ([
 	where, args := inboundSpamWhere(filter)
 	args = append(args, limit, offset)
 	rows, err := s.db.Query(
-		`SELECT id, inbound_domain, client_ip, from_addr, to_addr, subject, decision, engine, detail, created_at
+		`SELECT id, inbound_domain, client_ip, from_addr, to_addr, subject, decision, engine, detail, created_at,
+		        upstream_status, upstream_relay, upstream_reply, upstream_at
 		 FROM inbound_spam_log`+where+`
 		 ORDER BY created_at DESC, id DESC
 		 LIMIT ? OFFSET ?`,
@@ -180,14 +273,18 @@ func (s *Store) QueryInboundSpam(filter InboundSpamFilter, limit, offset int) ([
 	var out []InboundSpamRow
 	for rows.Next() {
 		var (
-			row     InboundSpamRow
-			created string
+			row          InboundSpamRow
+			created, upd string
 		)
 		if err := rows.Scan(&row.ID, &row.InboundDomain, &row.ClientIP, &row.From, &row.To,
-			&row.Subject, &row.Decision, &row.Engine, &row.Detail, &created); err != nil {
+			&row.Subject, &row.Decision, &row.Engine, &row.Detail, &created,
+			&row.Upstream, &row.UpstreamRelay, &row.UpstreamReply, &upd); err != nil {
 			return nil, fmt.Errorf("scan inbound_spam_log row: %w", err)
 		}
 		row.CreatedAt, _ = time.Parse(time.RFC3339, created)
+		if upd != "" {
+			row.UpstreamAt, _ = time.Parse(time.RFC3339, upd)
+		}
 		out = append(out, row)
 	}
 	return out, rows.Err()

internal/store/inboundspam_test.go

@@ -1,6 +1,7 @@
 package store
 
 import (
+	"strings"
 	"testing"
 	"time"
 )
@@ -344,3 +345,143 @@ func TestInsertInboundSpamOnce(t *testing.T) {
 		t.Errorf("rows = %d, %v; want 3", n, err)
 	}
 }
+
+// Accepted mail starts queued with its queue id; each delivery line moves it
+// on until sent or bounced, which no later or repeated line undoes. A
+// refusal, which has no queue id, and another recipient of the message are
+// left alone; the queue id goes by its own index.
+func TestInboundUpstream(t *testing.T) {
+	st := openTestStore(t)
+	accepted := InboundSpamEntry{
+		InboundDomain: "in.example.com", ClientIP: "203.0.113.7", From: "s@example.net", To: "a@in.example.com",
+		Decision: SpamDecisionAccept, Engine: SpamEngineSelfPost, QueueID: "4A1B2C3D", Upstream: UpstreamQueued,
+	}
+	other := accepted
+	other.To = "b@in.example.com"
+	refused := InboundSpamEntry{InboundDomain: "in.example.com", From: "s@example.net", To: "a@in.example.com",
+		Decision: SpamDecisionReject, Engine: SpamEnginePostfix, Detail: "550 5.1.1 unknown"}
+	for _, e := range []InboundSpamEntry{accepted, other, refused} {
+		if err := st.InsertInboundSpam(e); err != nil {
+			t.Fatal(err)
+		}
+	}
+	result := func(to string) InboundSpamRow {
+		t.Helper()
+		rows, err := st.QueryInboundSpam(InboundSpamFilter{}, 10, 0)
+		if err != nil {
+			t.Fatal(err)
+		}
+		for _, r := range rows {
+			if r.To == to && r.Decision == SpamDecisionAccept {
+				return r
+			}
+		}
+		t.Fatalf("no accepted row for %s", to)
+		return InboundSpamRow{}
+	}
+	if r := result("a@in.example.com"); r.Upstream != UpstreamQueued || !r.UpstreamAt.IsZero() {
+		t.Errorf("a new row = %q at %v, want queued and no time", r.Upstream, r.UpstreamAt)
+	}
+
+	at := time.Date(2026, 10, 16, 10, 16, 42, 0, time.UTC)
+	step := func(status, reply string, want int64) {
+		t.Helper()
+		n, err := st.UpdateInboundUpstream("4A1B2C3D", "A@IN.example.com", status, "mx.up.example[198.51.100.5]:25", reply, at)
+		if err != nil || n != want {
+			t.Fatalf("UpdateInboundUpstream(%s) = %d, %v; want %d", status, n, err, want)
+		}
+		at = at.Add(time.Minute)
+	}
+	step(UpstreamDeferred, "451 4.7.1 Greylisted", 1)
+	if r := result("a@in.example.com"); r.Upstream != UpstreamDeferred || r.UpstreamReply != "451 4.7.1 Greylisted" ||
+		r.UpstreamRelay != "mx.up.example[198.51.100.5]:25" || !r.UpstreamAt.Equal(time.Date(2026, 10, 16, 10, 16, 42, 0, time.UTC)) {
+		t.Errorf("after a deferral: %+v", r)
+	}
+	step(UpstreamSent, "250 2.0.0 Ok: queued as CE05D10261D", 1)
+	step(UpstreamDeferred, "451 4.7.1 Greylisted", 0) // read again after a restart
+	if r := result("a@in.example.com"); r.Upstream != UpstreamSent || r.UpstreamReply != "250 2.0.0 Ok: queued as CE05D10261D" {
+		t.Errorf("a sent row was moved back: %+v", r)
+	}
+	if r := result("b@in.example.com"); r.Upstream != UpstreamQueued {
+		t.Errorf("another recipient took the result: %+v", r)
+	}
+	if n, err := st.UpdateInboundUpstream("9999", "a@in.example.com", UpstreamSent, "", "250 ok", at); err != nil || n != 0 {
+		t.Errorf("an unknown queue id = %d, %v; want 0 (outbound mail)", n, err)
+	}
+	if n, err := st.UpdateInboundUpstream("", "a@in.example.com", UpstreamSent, "", "250 ok", at); err != nil || n != 0 {
+		t.Errorf("an empty queue id took %d rows, %v - a refusal has none", n, err)
+	}
+
+	// Expiry: the other recipient, still queued, bounces, and says so.
+	if _, err := st.UpdateInboundUpstream("4A1B2C3D", "b@in.example.com", UpstreamDeferred, "", "connect to mx.up.example[198.51.100.5]:25: Connection refused", at); err != nil {
+		t.Fatal(err)
+	}
+	if n, err := st.ExpireInboundUpstream("4A1B2C3D", at); err != nil || n != 1 {
+		t.Fatalf("ExpireInboundUpstream = %d, %v; want 1 (the sent row stays)", n, err)
+	}
+	if r := result("b@in.example.com"); r.Upstream != UpstreamBounced ||
+		r.UpstreamReply != "expired in the queue; last reply: connect to mx.up.example[198.51.100.5]:25: Connection refused" {
+		t.Errorf("after the expiry: %+v", r)
+	}
+	if err := st.InsertInboundSpam(InboundSpamEntry{InboundDomain: "in.example.com", To: "c@in.example.com",
+		Decision: SpamDecisionAccept, Engine: SpamEngineSelfPost, Upstream: "lost"}); err == nil {
+		t.Error("an unknown upstream status was stored")
+	}
+
+	for name, q := range map[string]string{"update": updateUpstreamQuery, "expire": expireUpstreamQuery} {
+		args := []any{"sent", "", "", "", "4A1B2C3D", "a@in.example.com"}
+		if name == "expire" {
+			args = []any{"", 255, "4A1B2C3D"}
+		}
+		if plan := explain(t, st, q, args...); !strings.Contains(plan, "USING INDEX idx_inbound_spam_log_queue_id") {
+			t.Errorf("%s does not use idx_inbound_spam_log_queue_id:\n%s", name, plan)
+		}
+	}
+}
+
+// A held message takes its result once released; a queue id Postfix uses
+// again detaches the rows of the message that had it - the open ones lose
+// their result, nothing reports it now - so the new message's lines and its
+// expiry reach only its own rows.
+func TestInboundUpstreamHeldAndReusedQueueID(t *testing.T) {
+	st := openTestStore(t)
+	old := InboundSpamEntry{InboundDomain: "in.example.com", To: "a@in.example.com",
+		Decision: SpamDecisionQuarantine, Engine: SpamEngineRspamd, QueueID: "4A1B", Upstream: UpstreamHeld}
+	if err := st.InsertInboundSpam(old); err != nil {
+		t.Fatal(err)
+	}
+	at := time.Date(2026, 10, 16, 10, 0, 0, 0, time.UTC)
+	if n, err := st.UpdateInboundUpstream("4A1B", "a@in.example.com", UpstreamDeferred, "", "451 later", at); err != nil || n != 1 {
+		t.Fatalf("a released held message: %d, %v", n, err)
+	}
+	if err := st.ForgetInboundQueueID("4A1B"); err != nil {
+		t.Fatal(err)
+	}
+	fresh := InboundSpamEntry{InboundDomain: "in.example.com", To: "a@in.example.com",
+		Decision: SpamDecisionAccept, Engine: SpamEngineSelfPost, QueueID: "4A1B", Upstream: UpstreamQueued}
+	if err := st.InsertInboundSpam(fresh); err != nil {
+		t.Fatal(err)
+	}
+	if n, err := st.ExpireInboundUpstream("4A1B", at); err != nil || n != 1 {
+		t.Fatalf("expiry of the reused id took %d rows, %v; want the new message's one", n, err)
+	}
+	rows, err := st.QueryInboundSpam(InboundSpamFilter{}, 10, 0)
+	if err != nil {
+		t.Fatal(err)
+	}
+	for _, r := range rows {
+		switch r.Decision {
+		case SpamDecisionQuarantine:
+			if r.Upstream != "" || r.UpstreamReply != "451 later" {
+				t.Errorf("the detached row = %+v, want no result and its last reply kept", r)
+			}
+		case SpamDecisionAccept:
+			if r.Upstream != UpstreamBounced {
+				t.Errorf("the new row = %+v, want bounced", r)
+			}
+		}
+	}
+	if plan := explain(t, st, forgetQueueIDQuery, "4A1B"); !strings.Contains(plan, "USING INDEX idx_inbound_spam_log_queue_id") {
+		t.Errorf("ForgetInboundQueueID does not use idx_inbound_spam_log_queue_id:\n%s", plan)
+	}
+}

internal/store/migrations/0012_inbound_upstream.sql

@@ -0,0 +1,20 @@
+-- What the upstream answered, on the inbound journal's rows
+-- (inbound-upstream-result, 2.10.0; owner, 2026-10-16). A row of mail
+-- accepted on port 25 keeps the message's queue id, which the inbound journal
+-- milter reads at end-of-message, and starts "queued" ("held" when the filter
+-- had it held in the queue); the log tailer puts
+-- each delivery attempt's result on it - the status, the host that answered
+-- ("" when Postfix had no session), its reply and when - from the postfix/smtp
+-- line of that queue id and recipient. sent and bounced are final. A refused
+-- message has no queue id and no result, and neither has a row written before
+-- this file.
+ALTER TABLE inbound_spam_log ADD COLUMN queue_id TEXT NOT NULL DEFAULT '';
+ALTER TABLE inbound_spam_log ADD COLUMN upstream_status TEXT NOT NULL DEFAULT ''
+    CHECK (upstream_status IN ('', 'queued', 'held', 'sent', 'deferred', 'bounced'));
+ALTER TABLE inbound_spam_log ADD COLUMN upstream_relay TEXT NOT NULL DEFAULT '';
+ALTER TABLE inbound_spam_log ADD COLUMN upstream_reply TEXT NOT NULL DEFAULT '';
+ALTER TABLE inbound_spam_log ADD COLUMN upstream_at TEXT NOT NULL DEFAULT '';
+
+-- The tailer finds a row by its queue id at every delivery line; only rows
+-- of accepted mail have one.
+CREATE INDEX idx_inbound_spam_log_queue_id ON inbound_spam_log(queue_id) WHERE queue_id <> '';

internal/store/schema_test.go

@@ -57,7 +57,7 @@ func TestBaselineSchema(t *testing.T) {
 		"user_inbound_domains":  "user_id inbound_domain_id",
 		"dmarc_reports":         "id domain reporter report_id period_begin period_end received_at contact_email policy_p policy_sp policy_pct policy_adkim policy_aspf pass_count fail_count recipient",
 		"dmarc_report_records":  "id report_row_id source_ip count disposition spf_result dkim_result header_from",
-		"inbound_spam_log":      "id inbound_domain client_ip from_addr to_addr subject decision engine detail created_at inbound_domain_id",
+		"inbound_spam_log":      "id inbound_domain client_ip from_addr to_addr subject decision engine detail created_at inbound_domain_id queue_id upstream_status upstream_relay upstream_reply upstream_at",
 		"inbound_spam_list":     "id list_type entry_type value note created_at",
 		"send_log_lines":        "id queue_id logged_at line",
 		"notify_state":          "key phase count mark since sent_at",
@@ -108,7 +108,7 @@ func TestBaselineSchema(t *testing.T) {
 	rows.Close()
 	wantIdx := []string{
 		"idx_applications_login_nocase", "idx_dmarc_report_records_report", "idx_dmarc_reports_domain", "idx_dmarc_reports_received",
-		"idx_inbound_spam_log_created_at", "idx_inbound_spam_log_domain_created_at", "idx_inbound_spam_log_domain_id_created_at",
+		"idx_inbound_spam_log_created_at", "idx_inbound_spam_log_domain_created_at", "idx_inbound_spam_log_domain_id_created_at", "idx_inbound_spam_log_queue_id",
 		"idx_send_log_app_login", "idx_send_log_app_login_created_at", "idx_send_log_created_at", "idx_send_log_domain", "idx_send_log_domain_id", "idx_send_log_domain_id_created_at",
 		"idx_send_log_lines_queue_id", "idx_send_log_open", "idx_send_log_queue_id", "idx_send_log_refusal_line", "idx_send_log_rejected",
 		"idx_sessions_expires_at",
@@ -119,8 +119,8 @@ func TestBaselineSchema(t *testing.T) {
 	}
 
 	var version, appID int64
-	if err := st.db.QueryRow("PRAGMA user_version").Scan(&version); err != nil || version != 11 {
-		t.Errorf("user_version = %d, %v; want 11", version, err)
+	if err := st.db.QueryRow("PRAGMA user_version").Scan(&version); err != nil || version != 12 {
+		t.Errorf("user_version = %d, %v; want 12", version, err)
 	}
 	if err := st.db.QueryRow("PRAGMA application_id").Scan(&appID); err != nil || appID != applicationID {
 		t.Errorf("application_id = %#x, %v; want %#x", appID, err, applicationID)
@@ -196,8 +196,8 @@ func TestOpenMigratesA20Database(t *testing.T) {
 	}
 	defer st.Close()
 	var version int
-	if err := st.db.QueryRow("PRAGMA user_version").Scan(&version); err != nil || version != 11 {
-		t.Errorf("user_version = %d, %v; want 11", version, err)
+	if err := st.db.QueryRow("PRAGMA user_version").Scan(&version); err != nil || version != 12 {
+		t.Errorf("user_version = %d, %v; want 12", version, err)
 	}
 	if ok, err := st.UserExists(); err != nil || !ok {
 		t.Errorf("the user of the 2.0 database: exists = %v, %v", ok, err)

internal/web/handlers/handlers_inbound_log.go

@@ -94,6 +94,7 @@ func (h *Handlers) HandleInboundLog(w http.ResponseWriter, r *http.Request) {
 		table[i] = out.NewRow(view.InLogRowInput{
 			ID: row.ID, Listable: inbound.Listable(store.SpamEntryAddress, row.From), At: row.CreatedAt, From: row.From, Client: row.ClientIP, To: row.To, Subject: row.Subject,
 			Decision: row.Decision, Engine: row.Engine, Detail: row.Detail,
+			Upstream: row.Upstream, UpstreamRelay: row.UpstreamRelay, UpstreamReply: row.UpstreamReply, UpstreamAt: row.UpstreamAt,
 		})
 	}
 	h.view.Render(w, http.StatusOK, "in-log", out.WithRows(table, page, lastPage))

internal/web/view/fixtures_test.go

@@ -448,29 +448,50 @@ func inLogFixture() *InLog {
 	p := NewInLog(admin(), 90, []string{"lists.example.org", "acme.io"},
 		InLogFilter{From: "2026-09-14", To: "2026-09-21"})
 	var id int64
-	row := func(clock, from, client, to, subject, decision, engine, detail string) InLogRow {
-		at, err := time.Parse("2006-01-02 15:04:05", "2026-09-21 "+clock)
+	clock := func(c string) time.Time {
+		at, err := time.Parse("2006-01-02 15:04:05", "2026-09-21 "+c)
 		if err != nil {
 			panic(err)
 		}
-		id++
-		return p.NewRow(InLogRowInput{ID: id, Listable: true, At: at, From: from, Client: client, To: to, Subject: subject,
-			Decision: decision, Engine: engine, Detail: detail})
+		return at
 	}
-	return p.WithRows([]InLogRow{
-		row("14:00:18", "t.berg@uni.example", "192.0.2.77", "dev@lists.example.org", "Re: [dev] patch series v3",
-			"accept", "rspamd", "no action, score 0.40 / 15.00"),
-		row("13:59:02", "invoice@partner-billing.example", "203.0.113.140", "owner@lists.example.org", "Outstanding invoice — action required",
-			"accept", "rspamd", "add header, score 9.80 / 15.00; PHISHING(5.00) FORGED_SENDER(3.00) R_SPF_FAIL(1.00)"),
+	// up is what the upstream answered: status, host, reply, when.
+	type up struct{ status, relay, reply, at string }
+	upRow := func(c, from, client, to, subject, decision, engine, detail string, u up) InLogRow {
+		id++
+		in := InLogRowInput{ID: id, Listable: true, At: clock(c), From: from, Client: client, To: to, Subject: subject,
+			Decision: decision, Engine: engine, Detail: detail,
+			Upstream: u.status, UpstreamRelay: u.relay, UpstreamReply: u.reply}
+		if u.at != "" {
+			in.UpstreamAt = clock(u.at)
+		}
+		return p.NewRow(in)
+	}
+	row := func(c, from, client, to, subject, decision, engine, detail string) InLogRow {
+		return upRow(c, from, client, to, subject, decision, engine, detail, up{})
+	}
+	const host = "mx.upstream.example[198.51.100.5]:25"
+	sent := upRow("14:00:18", "t.berg@uni.example", "192.0.2.77", "dev@lists.example.org", "Re: [dev] patch series v3",
+		"accept", "rspamd", "no action, score 0.40 / 15.00",
+		up{"sent", host, "250 2.0.0 Ok: queued as CE05D10261D", "14:00:19"})
+	bounced := upRow("13:59:02", "invoice@partner-billing.example", "203.0.113.140", "owner@lists.example.org", "Outstanding invoice — action required",
+		"accept", "rspamd", "add header, score 9.80 / 15.00; PHISHING(5.00) FORGED_SENDER(3.00) R_SPF_FAIL(1.00)",
+		up{"bounced", host, "550 5.7.1 Message rejected as spam by the upstream filter", "13:59:04"})
+	rest := []InLogRow{
 		row("13:57:41", "promo@bulk.example", "198.51.100.90", "sales@lists.example.org", "",
 			"reject", "postfix", "550 5.1.1 <sales@lists.example.org>: Recipient address rejected: User unknown in relay recipient table"),
 		row("13:51:30", "billing@partner.example", "198.51.100.12", "owner@lists.example.org", "",
 			"reject", "rspamd", "5.7.1 Spam message rejected"),
 		row("13:44:02", "hr@partner.example", "192.0.2.31", "jobs@acme.io", "",
 			"tempfail", "rspamd", "4.7.1 Try again later"),
-		row("13:30:55", "noreply@github.example", "192.0.2.200", "security@lists.example.org", "[advisory] new report",
-			"accept", "rspamd", "no action, score -98.10 / 15.00; SELFPOST_ALLOW_FROM(-100.00) R_DKIM_ALLOW(-0.20)"),
-	}, 1, 38)
+		upRow("13:30:55", "noreply@github.example", "192.0.2.200", "security@lists.example.org", "[advisory] new report",
+			"accept", "rspamd", "no action, score -98.10 / 15.00; SELFPOST_ALLOW_FROM(-100.00) R_DKIM_ALLOW(-0.20)",
+			up{"deferred", "", "connect to mx.upstream.example[198.51.100.5]:25: Connection refused", "13:45:12"}),
+	}
+	// The newest row is a message not tried yet; it is the seventh written.
+	queued := upRow("14:00:31", "ci@builds.example", "192.0.2.90", "dev@lists.example.org", "[ci] nightly build passed",
+		"accept", "rspamd", "no action, score 1.10 / 15.00", up{status: "queued"})
+	return p.WithRows(append([]InLogRow{queued, sent, bounced}, rest...), 1, 38)
 }
 
 // inFilterListsFixture is the mockup's Filter lists: three senders denied, two

internal/web/view/help.go

@@ -207,11 +207,16 @@ var inboundTopics = []HelpTopic{
 	}},
 	{ID: HelpInboundLog, Title: "Inbound log", Body: []Text{
 		Rich("One row per recipient of a message offered on port 25 for an inbound domain, with what was decided: ",
-			TagOf("accept", ""), " — handed on to the upstream; ", TagOf("reject", ""), " — refused for good; ",
+			TagOf("accept", ""), " — taken for the upstream; ", TagOf("reject", ""), " — refused for good; ",
 			TagOf("tempfail", ""), " — the sender was asked to come back later; ", TagOf("quarantine", ""), " — held by the filter. ",
 			Em("Why"), " names who decided. ", Code("rspamd"), " is the spam filter, with its action, the score against the reject threshold and the heaviest symbols; ",
 			Code("postfix"), " is the relay's own rule — an unknown recipient, a sender domain that does not exist — with its reply; ",
-			Code("selfpost"), " means nobody judged the message: it was relayed with no filter attached. Accept says what this server did, not what the upstream did with the message afterwards.",
+			Code("selfpost"), " means nobody judged the message: it was relayed with no filter attached. ",
+			Em("Upstream"), " says what became of an accepted message: ", TagOf("queued", ""), " — not tried yet; ",
+			TagOf("held", ""), " — held in the queue by the filter, not tried until it is released; ",
+			TagOf("sent", ""), " — the upstream took it; ", TagOf("deferred", ""),
+			" — the upstream put it off or could not be reached, and Postfix tries again; ", TagOf("bounced", ""),
+			" — the upstream refused it, or it waited in the queue too long, and the sender was sent a bounce, if it had a return address. It opens the last reply and the host that gave it. A refused message has no upstream result, and neither has a row logged before 2.10.0.",
 			Br(), Br(),
 			"Accepted mail is recorded as it passes; refused mail is read from ", Code("mail.log"),
 			", so its row has no subject, and a message refused after its text was sent is one row however many recipients it had. A refusal to relay for a domain that is not an inbound one is every scanner on the internet and is not recorded. Rows are kept for the number of days set in Settings, and never more than 10 000."),

internal/web/view/inbound_log.go

@@ -68,9 +68,9 @@ type InLog struct {
 
 // InLogRow is one recipient of one message: when it was decided, who the mail
 // was from (and the address of the server that offered it) and for, its subject,
-// the decision as a tag that opens the sheet saying who decided and why, and —
-// for the global role, who alone edits the filter lists — the way to correct
-// the decision.
+// the decision as a tag that opens the sheet saying who decided and why, what
+// the upstream made of it, and — for the global role, who alone edits the
+// filter lists — the way to correct the decision.
 type InLogRow struct {
 	Time    string
 	From    string
@@ -78,7 +78,13 @@ type InLogRow struct {
 	To      string
 	Subject string
 	Why     Sheet
-	Action  *Anchor
+	// Upstream is the upstream's answer, a tag that opens a sheet with the
+	// last reply; Pending is a message not tried yet - queued, or held by the
+	// filter - a plain tag. Neither for refused mail and rows from before
+	// 2.10.0, which show "—".
+	Upstream *Sheet
+	Pending  *Tag
+	Action   *Anchor
 }
 
 // InLogRowInput is what the journal holds about one row. Subject, Detail and
@@ -97,6 +103,12 @@ type InLogRowInput struct {
 	Decision string
 	Engine   string
 	Detail   string
+	// The upstream's answer (store.Upstream…): its status, "" for none, the
+	// host that gave it ("" when Postfix had no session), the reply and when.
+	Upstream      string
+	UpstreamRelay string
+	UpstreamReply string
+	UpstreamAt    time.Time
 }
 
 // NewInLog builds the log for a viewer. domains are the choices of the domain
@@ -105,7 +117,7 @@ type InLogRowInput struct {
 // change it and who edits the lists, is read from m.
 func NewInLog(m Meta, retentionDays int, domains []string, filter InLogFilter) *InLog {
 	m.Title, m.Section, m.Page = "Inbound log", "inbound", "log"
-	lead := Rich("What port 25 decided about each message, one row per recipient. Accepted mail is recorded as it passes, refused mail is read from ",
+	lead := Rich("What port 25 decided about each message and what the upstream answered, one row per recipient. Accepted mail is recorded as it passes, refused mail is read from ",
 		Code("mail.log"), "; the filter's verdict appears when the spam filter is on. Rows older than "+plural(int64(retentionDays), "day", "days")+" are deleted")
 	if m.IsGlobal {
 		lead = append(lead, Inline{Text: " — change that in "}, Link("/server/settings", "Settings"))
@@ -152,12 +164,50 @@ func (p *InLog) NewRow(in InLogRowInput) InLogRow {
 			Rows: whyRows(in.Decision, in.Engine, in.Detail, in.Subject),
 		},
 	}
+	switch in.Upstream {
+	case "queued", "held":
+		r.Pending = &Tag{Status: in.Upstream}
+	case "sent", "deferred", "bounced":
+		r.Upstream = &Sheet{
+			ID: "up-" + strconv.FormatInt(in.ID, 10), Tag: Tag{Status: in.Upstream}, Title: "Upstream",
+			Rows: upstreamRows(in),
+		}
+	}
 	if p.IsGlobal && in.Listable {
 		r.Action = senderAction(in.Decision, in.Engine, in.From)
 	}
 	return r
 }
 
+// upstreamRows is the content of the Upstream sheet: the host that answered
+// (none when Postfix could not open a session: the reply names the host
+// then), the last reply, when it came, and what follows a deferral or a
+// bounce - a bounce to the sender, unless the message had none to return to
+// (Postfix does not bounce mail from the null sender).
+func upstreamRows(in InLogRowInput) []SheetRow {
+	var rows []SheetRow
+	if in.UpstreamRelay != "" {
+		rows = append(rows, SheetRow{Label: "Host", Lines: []string{in.UpstreamRelay}, Mono: true})
+	}
+	if in.UpstreamReply != "" {
+		rows = append(rows, SheetRow{Label: "Reply", Lines: []string{in.UpstreamReply}, Mono: true})
+	}
+	if !in.UpstreamAt.IsZero() {
+		rows = append(rows, SheetRow{Label: "At", Lines: []string{FormatLogTime(in.UpstreamAt)}, Mono: true})
+	}
+	switch in.Upstream {
+	case "deferred":
+		rows = append(rows, SheetRow{Label: "Then", Lines: []string{"Postfix tries again; the message is in the queue"}})
+	case "bounced":
+		then := "The sender was sent a bounce"
+		if in.From == "" {
+			then = "No bounce: the message had no return address"
+		}
+		rows = append(rows, SheetRow{Label: "Then", Lines: []string{then}})
+	}
+	return rows
+}
+
 // whyRows is the content of a row's sheet: who decided, what they said, and
 // the subject whole, which the table clips. What was said has one of two
 // shapes, and the decision says which. Mail that passed was written by the
@@ -226,9 +276,9 @@ func (p *InLog) WithRows(rows []InLogRow, page, last int) *InLog {
 		p.Foot.Link = &Anchor{Href: InLogHref(p.filter, page+1), Label: "Older →"}
 	}
 	if p.IsGlobal {
-		p.Foot.End = Rich("A decision opens its reason · Allow / Deny sender opens ", Link(inboundFilterLists, "Filter lists"), " with the entry filled in")
+		p.Foot.End = Rich("A decision opens its reason, an upstream result its last reply · Allow / Deny sender opens ", Link(inboundFilterLists, "Filter lists"), " with the entry filled in")
 	} else {
-		p.Foot.End = Plain("A decision opens its reason")
+		p.Foot.End = Plain("A decision opens its reason, an upstream result its last reply")
 	}
 	return p
 }

internal/web/view/inbound_log_test.go

@@ -22,7 +22,18 @@ func TestInLogShowsTheRowsAndTheirFilters(t *testing.T) {
 		`<input class="input" type="date" name="from" value="2026-09-14" aria-label="From date">`,
 		`<input class="input" type="date" name="to" value="2026-09-21" aria-label="To date">`,
 		`href="/help#inbound-log" title="What the decisions mean"`,
-		`<th>Time, UTC</th><th>From</th><th>To</th><th>Subject</th><th>Decision</th><th></th></tr>`,
+		`<th>Time, UTC</th><th>From</th><th>To</th><th>Subject</th><th>Decision</th><th>Upstream</th><th></th></tr>`,
+		// what the upstream answered: a tag that opens its last reply, a
+		// plain tag while not tried, "—" for refused mail
+		`<button type="button" class="tag is-success is-light" popovertarget="up-1">sent</button><div class="sp-sheet" id="up-1" popover>`,
+		`<span class="tag is-success is-light">sent</span><h2>Upstream</h2>`,
+		`<tr><th>Host</th><td class="sp-mono sp-small">mx.upstream.example[198.51.100.5]:25</td></tr><tr><th>Reply</th><td class="sp-mono sp-small">250 2.0.0 Ok: queued as CE05D10261D</td></tr><tr><th>At</th><td class="sp-mono sp-small">09-21 14:00:19</td></tr></tbody>`,
+		`<button type="button" class="tag is-danger is-light" popovertarget="up-2">bounced</button>`,
+		`<tr><th>Then</th><td>The sender was sent a bounce</td></tr>`,
+		`<button type="button" class="tag is-warning is-light" popovertarget="up-6">deferred</button>`,
+		`<tbody><tr><th>Reply</th><td class="sp-mono sp-small">connect to mx.upstream.example[198.51.100.5]:25: Connection refused</td></tr><tr><th>At</th><td class="sp-mono sp-small">09-21 13:45:12</td></tr><tr><th>Then</th><td>Postfix tries again; the message is in the queue</td></tr></tbody>`,
+		`<td><span class="tag is-light">queued</span></td>`,
+		`</div></div></div></div></td><td class="sp-muted">—</td><td class="sp-actions">`,
 		`09-21 14:00:18`,
 		`t.berg@<wbr>uni.example<br><span class="sp-mono sp-muted sp-small">192.0.2.77</span>`,
 		`dev@<wbr>lists.example.org`, `title="Re: [dev] patch series v3"`,
@@ -36,14 +47,17 @@ func TestInLogShowsTheRowsAndTheirFilters(t *testing.T) {
 		`<tr><th>Verdict</th><td>add header, score 9.80 / 15.00</td></tr><tr><th>Symbols</th><td class="sp-mono sp-small">PHISHING(5.00)<br>FORGED_SENDER(3.00)<br>R_SPF_FAIL(1.00)</td></tr>`,
 		`<tr><th>Decided by</th><td>postfix</td></tr><tr><th>Reply</th><td class="sp-mono sp-small">550 5.1.1 &lt;sales@lists.example.org&gt;: Recipient address rejected: User unknown in relay recipient table</td></tr></tbody>`,
 		`Page 1 of 38`, `<a href="/inbound/log?from=2026-09-14&amp;p=2&amp;to=2026-09-21">Older →</a>`,
-		`A decision opens its reason · Allow / Deny sender opens <a href="/inbound/filter-lists">Filter lists</a> with the entry filled in`,
+		`A decision opens its reason, an upstream result its last reply · Allow / Deny sender opens <a href="/inbound/filter-lists">Filter lists</a> with the entry filled in`,
 	)
 	pageLacks(t, "Inbound log", out, `← Newer`, `data-poll`, `hx-get`, `<th>Why</th>`)
 	// A message Postfix itself refused offers no way into the lists: one Deny
-	// for each of the three accepted messages, one Allow for each the filter
+	// for each of the four accepted messages, one Allow for each the filter
 	// refused or put off.
-	if deny, allow := strings.Count(out, `>Deny sender</a>`), strings.Count(out, `>Allow sender</a>`); deny != 3 || allow != 2 {
-		t.Errorf("the fixture's six rows offer Deny %d times and Allow %d times, want 3 and 2", deny, allow)
+	if deny, allow := strings.Count(out, `>Deny sender</a>`), strings.Count(out, `>Allow sender</a>`); deny != 4 || allow != 2 {
+		t.Errorf("the fixture's seven rows offer Deny %d times and Allow %d times, want 4 and 2", deny, allow)
+	}
+	if n := strings.Count(out, `<td class="sp-muted">—</td>`); n != 3 {
+		t.Errorf("%d rows have no upstream result, want the three refused", n)
 	}
 
 	// Without the global role there is nowhere to change the retention, and
@@ -308,3 +322,18 @@ func TestWhyRows(t *testing.T) {
 		}
 	}
 }
+
+// A message the filter had held is a plain tag until it is released, and a
+// bounce of mail from the null sender says none went back.
+func TestInLogHeldAndABounceWithNoReturnAddress(t *testing.T) {
+	p := NewInLog(admin(), 90, nil, InLogFilter{})
+	at := time.Date(2026, 9, 21, 14, 0, 0, 0, time.UTC)
+	out := renderSignedIn(t, "in-log", p.WithRows([]InLogRow{
+		p.NewRow(InLogRowInput{ID: 1, At: at, From: "a@example.net", To: "b@acme.io", Decision: "quarantine", Engine: "rspamd", Upstream: "held"}),
+		p.NewRow(InLogRowInput{ID: 2, At: at, To: "b@acme.io", Decision: "accept", Engine: "selfpost",
+			Upstream: "bounced", UpstreamReply: "550 5.1.1 no such user", UpstreamAt: at}),
+	}, 1, 1))
+	pageHas(t, "Inbound log", out, `<td><span class="tag is-primary is-light">held</span></td>`,
+		`<tr><th>Then</th><td>No bounce: the message had no return address</td></tr>`)
+	pageLacks(t, "Inbound log", out, `The sender was sent a bounce`, `<th>Host</th>`)
+}

internal/web/view/templates/in_log.html

@@ -1,7 +1,8 @@
 {{/* Inbound log (mockup in-log.html): what port 25 decided about each message
      offered for an inbound domain, one row per recipient, newest first,
      filtered by domain, decision and day. It does not poll. The decision is a
-     tag that opens a sheet with who decided and why. The last cell is the way
+     tag that opens a sheet with who decided and why; the upstream's answer one
+     with its last reply (queued or held, not tried yet, is a plain tag). The last cell is the way
      to correct a decision in Filter lists, and only the global role, who alone
      edits the lists, is given it. */}}
 {{define "content"}}
@@ -10,9 +11,9 @@
 {{template "box_open" .Messages}}
 {{if .Rows}}
 <div class="table-container"><table class="table is-fullwidth is-hoverable">
-  <thead><tr><th>Time, UTC</th><th>From</th><th>To</th><th>Subject</th><th>Decision</th><th></th></tr></thead>
+  <thead><tr><th>Time, UTC</th><th>From</th><th>To</th><th>Subject</th><th>Decision</th><th>Upstream</th><th></th></tr></thead>
   <tbody>{{range .Rows}}
-    <tr><td class="sp-mono sp-muted sp-nowrap sp-small">{{.Time}}</td><td>{{wbr_at .From}}{{if .Client}}<br><span class="sp-mono sp-muted sp-small">{{.Client}}</span>{{end}}</td><td>{{wbr_at .To}}</td>{{if .Subject}}<td class="sp-clip" title="{{.Subject}}">{{.Subject}}</td>{{else}}<td class="sp-clip sp-muted">—</td>{{end}}<td>{{template "sheet_tag" .Why}}</td><td class="sp-actions">{{if .Action}}<a href="{{.Action.Href}}">{{.Action.Label}}</a>{{end}}</td></tr>{{end}}
+    <tr><td class="sp-mono sp-muted sp-nowrap sp-small">{{.Time}}</td><td>{{wbr_at .From}}{{if .Client}}<br><span class="sp-mono sp-muted sp-small">{{.Client}}</span>{{end}}</td><td>{{wbr_at .To}}</td>{{if .Subject}}<td class="sp-clip" title="{{.Subject}}">{{.Subject}}</td>{{else}}<td class="sp-clip sp-muted">—</td>{{end}}<td>{{template "sheet_tag" .Why}}</td>{{if .Upstream}}<td>{{template "sheet_tag" .Upstream}}</td>{{else if .Pending}}<td>{{template "tag" .Pending}}</td>{{else}}<td class="sp-muted">—</td>{{end}}<td class="sp-actions">{{if .Action}}<a href="{{.Action.Href}}">{{.Action.Label}}</a>{{end}}</td></tr>{{end}}
   </tbody>
 </table></div>
 {{template "box_foot" .Foot}}