Files
selfpost/cmd/panel/dmarc_ingest.go
T
mixandClaude Opus 5.5 006bed7022
test / test (push) Canceled after 0s
audit 4: DNS outages unknown, DMARC limits said, typed Health, one TLS mode per upstream
M14, M15: queryEach gives each resolver 2 s within the check's context and
asks the one that answered last first; an address or PTR lookup not
answered is Unknown, an answered mismatch beside it still an error;
Checker.Server keeps the last answer's addresses, so SPF does not go Unknown
with it. Notifications report faults only, now tested with SPF unknown
alone and beside a wrong DKIM.

DMARC reports: tests of malformed XML, gzip and zip bombs, a message over
the limit, the service's Resync, hosted suggestion and validation. The
finding: both limits cut silently and an oversized report failed as
damaged; readAtMost refuses it for its size (MaxMessage 10 MiB, moved into
IngestMessage).

healthReadings replaces map[string]any for Health and Overview.

L5: an inbound upstream has one TLS mode - a second domain to the same
[host]:port with another mode is refused, naming the first; the TLS policy
map holds each next hop once.

Tested on the test server: go vet + go test of 25 packages, make e2e (all
pass, 631 s) on this tree.

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>
2026-10-15 12:15:58 +03:00

107 lines
3.7 KiB
Go

package main
import (
"errors"
"fmt"
"log"
"os"
"path/filepath"
"strings"
"time"
"github.com/mixeme/selfpost/internal/dmarc"
"github.com/mixeme/selfpost/internal/store"
)
func runDMARCIngestMode() error {
cfg := loadConfig()
if !cfg.dmarcEnabled {
return fmt.Errorf("dmarc ingest invoked but DMARC_REPORTS_ENABLE is not true")
}
st, err := store.Open(cfg.dbPath)
if err != nil {
return err
}
defer st.Close()
recipient := ingestRecipient(os.Args[1:])
if err := dmarc.IngestMessage(st, os.Stdin, recipient, time.Now().UTC()); err != nil {
if !errors.Is(err, dmarc.ErrRejected) {
return err
}
// Not a report this relay keeps. It is dropped: deferring would have
// Postfix try it again for days, and a bounce would go to an envelope
// sender anyone can write - the report addresses are public. Postfix
// 3.7.11: exit 0 is PIPE_STAT_OK, logged "status=sent (delivered via
// ... service ...)" (src/global/pipe_command.c, pipe_command();
// src/pipe/pipe.c, eval_command_status()); a 4.x.x status defers until
// maximal_queue_lifetime and a 5.x.x one bounces, either way a notice
// to the sender (src/qmgr/qmgr_active.c, src/global/bounce.c).
if incrErr := st.IncrDMARCParseFailures(); incrErr != nil {
log.Printf("dmarc ingest: record failure: %v", incrErr)
}
logRejected(err)
}
return nil
}
// logRejected leaves the reason in the mail log. Postfix puts the start of
// what a delivery command wrote - about a hundred bytes - into its own line
// for the message ("status=sent (delivered via dmarc-ingest service (...))"),
// so the reason goes out first and bare: no prefix, no date, no recipient,
// all of which that line already has. Postfix 3.7.11, src/pipe/pipe.c,
// eval_command_status(): " (%.100s)" of the output, which
// src/global/pipe_command.c takes from stdout and stderr together. postlog is
// no use here: pipe(8) starts the command without the group that may write to
// Postfix's log socket (src/util/set_ugid.c, set_ugid(): setgroups() to the
// user's one group). Nor does postlog bring the group with it: upstream
// installs it set-gid, Debian's package does not - measured in the image,
// 2026-10-15: /usr/sbin/postlog is -rwxr-xr-x root:root (postfix
// 3.7.11-0+deb12u1), and dpkg-statoverride lists only postdrop and
// postqueue (assumptions A-43).
func logRejected(reason error) {
fmt.Fprintln(os.Stderr, "dropped: "+logSafe(strings.TrimPrefix(reason.Error(), dmarc.ErrRejected.Error()+": ")))
}
// logSafe makes a reason fit for a log line. Parts of it are the sender's own
// bytes - a header line, a file name inside an archive, a piece of XML - so it
// is cut short and anything that is not printable ASCII becomes "?", whatever
// Postfix would have done with it.
func logSafe(s string) string {
const max = 200
if len(s) > max {
s = s[:max]
}
return strings.Map(func(r rune) rune {
if r < 0x20 || r > 0x7e {
return '?'
}
return r
}, s)
}
// ingestRecipient is the report address the message was delivered to. Postfix's
// pipe(8) hands it over as an argument (${recipient} in the service's argv,
// build/postfix-config.sh) - it sets no RECIPIENT variable, that is local(8).
// Postfix 3.7.11, src/pipe/pipe.c, deliver_message(): pipe_command() gets only
// CA_PIPE_CMD_EXPORT(export_environment), no extra environment;
// src/local/command.c sets "RECIPIENT".
// Without it the check that a report came to its own domain's address is
// skipped.
func ingestRecipient(args []string) string {
for _, a := range args {
if a == "-dmarc-ingest" {
continue
}
return strings.ToLower(strings.TrimSpace(a))
}
return ""
}
func isDMARCIngestInvocation() bool {
if len(os.Args) > 1 && os.Args[1] == "-dmarc-ingest" {
return true
}
return filepath.Base(os.Args[0]) == "dmarc-ingest"
}