Commit `35954391f3`

35954391f3a289b7150b2c80e5723ad47f45d88e

parent: bc76b6f008

Verified · cmc

cmc <hello@cleberg.net> · 2026-09-28 07:41 UTC

sshd: unregistered-key message names the fingerprint and the real host

Ref #268

Layout: unified · split

CHANGELOG.org +2

	@@ -87,6 +87,8 @@ for the eighteen commands whose CLI path differs from the registry's
87	usage line a wrong-argument refusal does. Outside the CLI a usage	87	usage line a wrong-argument refusal does. Outside the CLI a usage
88	refusal reads =usage: ssh git@<host> ...= on every surface,	88	refusal reads =usage: ssh git@<host> ...= on every surface,
89	including the error text of the web UI and the JSON API (#267).	89	including the error text of the web UI and the JSON API (#267).
		90	- An unregistered SSH key is refused with its own fingerprint and the
		91	real host, and both the web and ssh paths to register (#268).
90		92
91	* v1.36.0 — 2026-09-23	93	* v1.36.0 — 2026-09-23
92		94

internal/sshd/sshd.go +8 −2

 		return protocol.ExitUsage
 	}
 	if len(argv) == 0 || argv[0] != "register" {
-		fmt.Fprintf(ch.Stderr(), "this key is not registered here. Create an account with:\n  ssh <host> register --username <name> %s\n",
+		host := s.cfg.SiteHost()
-			map[string]string{"open": "--email <address>", "invite": "--invite <code>"}[s.cfg.Registration.Mode])
+		fp := ssh.FingerprintSHA256(pub)
+		flag := map[string]string{"open": "--email <address>", "invite": "--invite <code>"}[s.cfg.Registration.Mode]
+		fmt.Fprintf(ch.Stderr(),
+			"this key (%s) is not registered on %s.\n"+
+				"already have an account? add it at https://%s/settings#keys\n"+
+				"new here? ssh git@%s register --username <name> %s\n",
+			fp, host, host, host, flag)
 		return protocol.ExitDenied
 	}
 	return control.RunRegister(s.cfg, s.st, pub, argv, ch, ch.Stderr())

internal/sshd/sshd_test.go +69

	@@ -226,3 +226,72 @@ func TestStopEndsFollow(t *testing.T) {
226	t.Errorf("stderr %q", stderr.String())	226	t.Errorf("stderr %q", stderr.String())
227	}	227	}
228	}	228	}
		229
		230	// An unregistered key is told its own fingerprint and the real host, and
		231	// offered both the web and the ssh path to register.
		232	func TestUnregisteredKeyMessageNamesFingerprintAndHost(t *testing.T) {
		233	root := t.TempDir()
		234	st, err := store.Open(filepath.Join(root, "gitbay.db"))
		235	if err != nil {
		236	t.Fatal(err)
		237	}
		238	t.Cleanup(func() { st.Close() })
		239	if err := st.MigrateUp(); err != nil {
		240	t.Fatal(err)
		241	}
		242
		243	cfg := config.Default()
		244	cfg.Server.Root = root
		245	cfg.Server.SiteURL = "https://forge.test"
		246	cfg.Registration.Mode = "open"
		247	srv, err := New(cfg, st)
		248	if err != nil {
		249	t.Fatal(err)
		250	}
		251	ln, err := net.Listen("tcp", "127.0.0.1:0")
		252	if err != nil {
		253	t.Fatal(err)
		254	}
		255	go srv.Serve(ln)
		256	t.Cleanup(func() { ln.Close() })
		257
		258	_, priv, err := ed25519.GenerateKey(rand.Reader)
		259	if err != nil {
		260	t.Fatal(err)
		261	}
		262	signer, err := ssh.NewSignerFromKey(priv)
		263	if err != nil {
		264	t.Fatal(err)
		265	}
		266
		267	client, err := ssh.Dial("tcp", ln.Addr().String(), &ssh.ClientConfig{
		268	User: "git",
		269	Auth: []ssh.AuthMethod{ssh.PublicKeys(signer)},
		270	HostKeyCallback: ssh.InsecureIgnoreHostKey(),
		271	Timeout: 5 * time.Second,
		272	})
		273	if err != nil {
		274	t.Fatal(err)
		275	}
		276	t.Cleanup(func() { client.Close() })
		277
		278	sess, err := client.NewSession()
		279	if err != nil {
		280	t.Fatal(err)
		281	}
		282	defer sess.Close()
		283	var stderr bytes.Buffer
		284	sess.Stderr = &stderr
		285
		286	var exit *ssh.ExitError
		287	if err := sess.Run("whoami"); !errors.As(err, &exit) \|\| exit.ExitStatus() != 4 {
		288	t.Fatalf("whoami ended with %v, want exit 4", err)
		289	}
		290
		291	fp := ssh.FingerprintSHA256(signer.PublicKey())
		292	for _, want := range []string{fp, "forge.test", "https://forge.test/settings#keys", "ssh git@forge.test register"} {
		293	if !strings.Contains(stderr.String(), want) {
		294	t.Errorf("message missing %q:\n%s", want, stderr.String())
		295	}
		296	}
		297	}

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