Files
mixandClaude Opus 5.5 c2f63d2789
test / test (push) Canceled after 0s
panel-dkim-signing: the queue by name, and findings of the reviews
The first rollout of faa3c11 to the test server crash-looped: without
opendkim the image's package accounts got other numbers (postfix 101 ->
100, postdrop 103 -> 102), the queue under /data kept the old ones, and
postsuper, which "postfix check" runs as the mail owner
(src/postsuper/postsuper.c:1442), could not open it. Rolled back within
five minutes. The entrypoint now hands an existing queue to Postfix's users
by name before postfix-config.sh, and again after it (own_queue).

Technical review (F1-F10):
- F1 high: a backup of an upgraded installation carried /data/opendkim, a
  restore left it root's, and the panel refused every start. The tree is
  left out of archives, and the entrypoint makes it the panel's alone
  (0700/0600; also the security review's F3 - nothing of 2.8 needs the
  group any more; a 2.7.x start re-normalises it).
- F2: List-Unsubscribe-Post is signed (RFC 8058); Sender too (security F1).
- F3: SetServerName keeps the name in lower case - a key written under
  "Mail.Example.com" was never found. Only the DKIM side: the SASL realm
  is compared as written.
- F4: the signer rewrites the selector table at every start
  (WriteSelectors, replacing EnsureServerSigned), and tries again every
  10 s while a rewrite fails.
- F5: e2e signature_over_awkward_headers (folded, tab-led, no space, two
  To:, 8-bit body, List-Unsubscribe-Post) checked by dkimpy;
  TestStartsOnA27Data starts on a 2.7 /data (old key tree, a queue of
  foreign numbers) and checks the copied key signs, the old tree's modes
  and the queue's owners; unit tests for repeated headers and the header
  limit.
- F6: the table's writers are serialised (tableMu).
- F7: the table is read for every message; keys the table no longer names
  are dropped from memory.
- F8: the signature's value brings its own space (SMFIP_HDR_LEADSPC gets
  none from Postfix, cleanup_milter.c:1085).
- F9: a body line over 998 bytes is logged with its domain: Postfix's SMTP
  client breaks it after signing (smtp_proto.c:1266-1274).
- F10: the keys are copied while /data/dkim holds none (not only when it
  is absent), after the old tree is made the panel's (an install from 2.6
  had another uid); the plan's rollback note says what a rollback keeps.

Security review: F2 a header section over 1 MiB is refused (552 5.3.4)
and the kept headers freed once the block is built - fifty connections of
header-only messages could take the panel down; F5 the shown headers a
message has (Subject, Date, To, Cc, Reply-To, Sender) are over-signed,
only when present, since cleanup adds a missing Date: after the milters.
F1 (holding Sender: to the login like From:) changes what is refused and
waits for the owner.

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>
2026-10-16 01:44:59 +03:00

148 lines
4.1 KiB
Go

package domain
import (
"os"
"path/filepath"
"runtime"
"strings"
"testing"
)
func TestRenderSelectors(t *testing.T) {
// Deliberately out of order to exercise the deterministic sort.
domains := []SigningDomain{
{Name: "zeta.example", Selector: "selfpost"},
{Name: "alpha.example", Selector: "sel2"},
}
got, err := renderSelectors(domains)
if err != nil {
t.Fatalf("renderSelectors: %v", err)
}
if want := "alpha.example sel2\nzeta.example selfpost\n"; string(got) != want {
t.Errorf("selector table =\n%q\nwant\n%q", got, want)
}
if empty, err := renderSelectors(nil); err != nil || len(empty) != 0 {
t.Errorf("renderSelectors(nil) = %q, %v; want an empty table", empty, err)
}
}
func TestAssertConfigSafeRejectsInjection(t *testing.T) {
bad := []struct{ name, sel string }{
{"exa mple.com", "selfpost"},
{"example.com\nInject yes", "selfpost"},
{"example.com", "sel:evil"},
{"../etc", "selfpost"},
{"", "selfpost"},
{"example.com", ""},
{"..", "selfpost"},
{".", "selfpost"},
{"example.com", ".."},
}
for _, b := range bad {
if err := assertConfigSafe(b.name, b.sel); err == nil {
t.Errorf("assertConfigSafe(%q,%q) = nil, want error", b.name, b.sel)
}
}
if err := assertConfigSafe("example.com", "selfpost"); err != nil {
t.Errorf("assertConfigSafe of a clean pair errored: %v", err)
}
}
// newTestKeys builds a manager rooted at a temp dir.
func newTestKeys(t *testing.T) *Keys {
t.Helper()
return NewKeys(t.TempDir())
}
func TestEnsureKeyReusesExisting(t *testing.T) {
o := newTestKeys(t)
created, err := o.EnsureKey("example.com", "selfpost")
if err != nil {
t.Fatalf("EnsureKey: %v", err)
}
if !created {
t.Fatal("expected a new key to be created")
}
first, err := os.ReadFile(o.keyPath("example.com", "selfpost"))
if err != nil {
t.Fatal(err)
}
created, err = o.EnsureKey("example.com", "selfpost")
if err != nil {
t.Fatalf("EnsureKey (second): %v", err)
}
if created {
t.Error("expected existing key to be reused, not regenerated")
}
second, _ := os.ReadFile(o.keyPath("example.com", "selfpost"))
if string(first) != string(second) {
t.Error("key file changed on reuse — published DNS record would break")
}
}
// The key and the table are the panel's alone: no other program reads them.
func TestRebuildWritesThePanelsOwnFiles(t *testing.T) {
o := newTestKeys(t)
if _, err := o.EnsureKey("example.com", "selfpost"); err != nil {
t.Fatal(err)
}
if err := o.Rebuild([]SigningDomain{{Name: "example.com", Selector: "selfpost"}}); err != nil {
t.Fatalf("Rebuild: %v", err)
}
if got, err := os.ReadFile(o.selectorsPath); err != nil || string(got) != "example.com selfpost"+"\n" {
t.Errorf("selector table after Rebuild = %q, %v", got, err)
}
if runtime.GOOS == "windows" {
return // no Unix modes
}
for path, want := range map[string]os.FileMode{
o.selectorsPath: 0o600,
o.keyPath("example.com", "selfpost"): 0o600,
filepath.Join(o.keysDir, "example.com"): 0o700,
} {
fi, err := os.Stat(path)
if err != nil {
t.Fatal(err)
}
if got := fi.Mode().Perm(); got != want {
t.Errorf("%s: mode %o, want %o", path, got, want)
}
}
}
func TestRemoveKey(t *testing.T) {
o := newTestKeys(t)
if _, err := o.EnsureKey("example.com", "selfpost"); err != nil {
t.Fatal(err)
}
if err := o.RemoveKey("example.com"); err != nil {
t.Fatalf("RemoveKey: %v", err)
}
if _, err := os.Stat(filepath.Join(o.keysDir, "example.com")); !os.IsNotExist(err) {
t.Error("key directory still present after RemoveKey")
}
// Removing a non-existent key is not an error.
if err := o.RemoveKey("example.com"); err != nil {
t.Errorf("RemoveKey on missing dir errored: %v", err)
}
}
func TestRecordFromWrittenKey(t *testing.T) {
o := newTestKeys(t)
if _, err := o.EnsureKey("example.com", "selfpost"); err != nil {
t.Fatal(err)
}
rec, err := o.Record("example.com", "selfpost")
if err != nil {
t.Fatalf("Record: %v", err)
}
if rec.Name != "selfpost._domainkey.example.com" {
t.Errorf("record name = %q", rec.Name)
}
if !strings.HasPrefix(rec.Value, "v=DKIM1;") {
t.Errorf("record value = %q", rec.Value)
}
}