A wrong passphrase gives an error that says so (closes #157)

A passphrase that did not decrypt the passphrase unlocker failed with age's
"no identity matched any of the recipients" and advice to give the vault a
new unlocker from its mnemonic, which would replace an unlocker that works.
GetIdentity now turns that age error into "wrong passphrase for unlocker
<id>", wrapping the new secret.ErrWrongPassphrase, and withMnemonicAdvice
leaves it alone, as it does when no passphrase was read. A passphrase from
SB_UNLOCK_PASSPHRASE and a typed one both reach this code. A priv.age that
is not an age file keeps the advice.

Judgement call: age cannot tell a wrong passphrase from a damaged key inside
a priv.age whose header reads, so that case now reads as a wrong passphrase.

Model: opus-5-5

README.md

@@ -197,7 +197,8 @@ for confirmation, naming the version, the secret and its vault (see
 
 #### `secret generate mnemonic`
 
-Generates a cryptographically secure BIP39 mnemonic phrase.
+Generates a cryptographically secure BIP39 mnemonic phrase and prints it to
+stdout. The warning to keep it safe goes to stderr.
 
 #### `secret generate secret <name> [--length=16] [--type=base58] [--force]`
 

TODO.md

@@ -18,6 +18,22 @@ https://git.eeqj.de/sneak/secret/milestone/12
 
 # Completed Steps
 
+- 2026-10-14: A wrong passphrase, from `SB_UNLOCK_PASSPHRASE` or typed at the
+  prompt, gives the error `wrong passphrase for unlocker <id>`
+  (https://git.eeqj.de/sneak/secret/issues/157). It used to be age's "no
+  identity matched any of the recipients", followed by advice to give the vault
+  a new unlocker from its mnemonic, which would have replaced an unlocker that
+  works. The error now wraps `secret.ErrWrongPassphrase` and carries no advice
+  to use the mnemonic. A `priv.age` that is not an age file still gets that
+  advice.
+- 2026-10-14: `secret generate mnemonic`, `secret vault list` and
+  `secret unlocker list` print their output to stdout, as `secret list` does, so
+  it can be piped or captured (https://git.eeqj.de/sneak/secret/issues/138).
+  They printed with cobra's `cmd.Println` and `cmd.Printf`, which write to
+  stderr when no output writer is set, so `secret vault list --json | jq`
+  received nothing. "No versions found" from `secret version list` moved to
+  stdout too. Messages such as "Created vault", and the warning after the
+  mnemonic, stay on stderr.
 - 2026-10-14: Removing the current unlocker no longer leaves the vault unable to
   open through the unlockers it still has
   (https://git.eeqj.de/sneak/secret/issues/137). `current-unlocker` went on

internal/cli/generate.go

@@ -103,7 +103,7 @@ func (cli *Instance) GenerateMnemonic(cmd *cobra.Command) error {
 	}
 
 	// Output mnemonic to stdout
-	cmd.Println(mnemonic)
+	_, _ = fmt.Fprintln(cmd.OutOrStdout(), mnemonic)
 
 	// Output helpful information to stderr
 	fmt.Fprintln(os.Stderr, "")

internal/cli/stdout_stderr_test.go

@@ -2,6 +2,7 @@ package cli_test
 
 import (
 	"bytes"
+	"encoding/json"
 	"os/exec"
 	"path/filepath"
 	"strings"
@@ -9,6 +10,7 @@ import (
 
 	"github.com/stretchr/testify/assert"
 	"github.com/stretchr/testify/require"
+	"sneak.berlin/go/secret/internal/bip39"
 	"sneak.berlin/go/secret/internal/secret"
 )
 
@@ -90,3 +92,66 @@ func TestGetCommandOutputsToStdout(t *testing.T) {
 	// Nothing should be in stderr
 	assert.Empty(t, stderr.String(), "stderr should be empty")
 }
+
+// TestMnemonicAndListingsOutputToStdout tests that 'secret generate
+// mnemonic', 'secret vault list' and 'secret unlocker list' print their
+// output to stdout, so that it can be piped
+func TestMnemonicAndListingsOutputToStdout(t *testing.T) {
+	t.Parallel()
+
+	tempDir := t.TempDir()
+	secretPath := secretBinaryPath(t)
+
+	// run runs the secret binary and returns what it wrote to stdout and to
+	// stderr
+	run := func(args ...string) (string, string) {
+		//nolint:gosec // G204: test executes the freshly built secret binary
+		cmd := exec.CommandContext(t.Context(), secretPath, args...)
+		cmd.Env = []string{
+			secret.EnvStateDir + "=" + tempDir,
+			secret.EnvMnemonic + "=" + testMnemonic,
+			secret.EnvUnlockPassphrase + "=test-passphrase",
+			"PATH=/usr/bin:/bin",
+		}
+
+		var stdout, stderr bytes.Buffer
+
+		cmd.Stdout = &stdout
+		cmd.Stderr = &stderr
+
+		err := cmd.Run()
+		require.NoError(t, err, "%v should succeed: %s", args, stderr.String())
+
+		return stdout.String(), stderr.String()
+	}
+
+	stdout, stderr := run("generate", "mnemonic")
+	assert.True(t, bip39.IsMnemonicValid(strings.TrimSpace(stdout)),
+		"stdout should hold the mnemonic, not %q", stdout)
+	assert.Contains(t, stderr, "Save this mnemonic phrase securely",
+		"the warning should be on stderr")
+
+	run("init")
+
+	stdout, _ = run("vault", "list", "--json")
+
+	var vaults map[string]any
+
+	require.NoError(t, json.Unmarshal([]byte(stdout), &vaults),
+		"stdout should hold the vaults as JSON, not %q", stdout)
+	assert.Equal(t, "default", vaults["currentVault"])
+
+	stdout, _ = run("unlocker", "list", "--json")
+
+	var unlockers map[string]any
+
+	require.NoError(t, json.Unmarshal([]byte(stdout), &unlockers),
+		"stdout should hold the unlockers as JSON, not %q", stdout)
+	assert.Len(t, unlockers["unlockers"], 1)
+
+	stdout, _ = run("vault", "list")
+	assert.Contains(t, stdout, "default (current)")
+
+	stdout, _ = run("unlocker", "list")
+	assert.Contains(t, stdout, "Total: 1 unlocker(s)")
+}

internal/cli/unlock_failure_test.go

@@ -1,12 +1,12 @@
 // Unlock Failure Tests
 //
 // When a vault cannot be opened through its current unlocker, because a
-// file the unlocker needs is missing or the passphrase is wrong, the error
+// file the unlocker needs is missing, the error keeps its cause and ends by
-// keeps its cause and ends by saying that the mnemonic still opens that
+// saying that the mnemonic still opens that vault, but only for a vault that
-// vault, but only for a vault that the mnemonic does open, and not when the
+// the mnemonic does open, and not when the passphrase could not be read at
-// passphrase could not be read at all. When the current unlocker does not
+// all. A wrong passphrase gives an error that says so, without that advice.
-// exist and the vault has another that `secret unlocker select` accepts, the
+// When the current unlocker does not exist and the vault has another that
-// error says to select one instead.
+// `secret unlocker select` accepts, the error says to select one instead.
 // When a secret's current file is missing, the error says how to make a
 // version current again. Each test that pins such advice also follows it.
 
@@ -20,7 +20,6 @@ import (
 	"path/filepath"
 	"testing"
 
-	"filippo.io/age"
 	"github.com/awnumar/memguard"
 	"github.com/spf13/afero"
 	"github.com/spf13/cobra"
@@ -164,26 +163,48 @@ func TestUnlockFailureNamesMnemonic(t *testing.T) {
 	}
 }
 
-// TestWrongPassphraseNamesMnemonic checks the error of `secret get` given a
+// TestWrongPassphraseNamesPassphrase checks the error of `secret get` given
-// passphrase that does not decrypt the passphrase unlocker: it keeps age's
+// a passphrase that does not decrypt the passphrase unlocker: it says that
-// error and ends with the advice that the mnemonic still opens the vault.
+// the passphrase is wrong, without the advice to use the mnemonic, since the
-func TestWrongPassphraseNamesMnemonic(t *testing.T) {
+// unlocker still opens the vault with the right passphrase. The test then
+// gives the right passphrase.
+func TestWrongPassphraseNamesPassphrase(t *testing.T) {
 	t.Parallel()
 
-	_, c := newUnlockTestCLI(t, newTwoVaultFs(t))
+	unlockerDir, c := newUnlockTestCLI(t, newTwoVaultFs(t))
 	c.UnlockPassphrase = memguard.NewBufferFromBytes([]byte("wrong passphrase"))
 	t.Cleanup(c.UnlockPassphrase.Destroy)
 
 	err := c.GetSecret(discardCmd(), "x")
 
-	var noMatch *age.NoIdentityMatchError
+	require.ErrorIs(t, err, secret.ErrWrongPassphrase)
-
+	assert.NotContains(t, err.Error(), mnemonicAdvice)
-	require.ErrorAs(t, err, &noMatch)
-
 	require.EqualError(t, err, "failed to unlock vault: "+
 		"failed to get long-term key: failed to get unlocker identity: "+
-		"failed to decrypt unlocker private key: failed to create decryptor: "+
+		"wrong passphrase for unlocker "+filepath.Base(unlockerDir))
-		noMatch.Error()+mnemonicAdvice)
+
+	c.UnlockPassphrase = memguard.NewBufferFromBytes([]byte(testPassphrase))
+	t.Cleanup(c.UnlockPassphrase.Destroy)
+	assert.Equal(t, "value", getSecret(t, c, "x"))
+}
+
+// TestDamagedUnlockerNamesMnemonic checks the error of `secret get` when the
+// passphrase unlocker's priv.age is not an age file: the passphrase is not
+// blamed, and the error ends with the advice that the mnemonic still opens
+// the vault.
+func TestDamagedUnlockerNamesMnemonic(t *testing.T) {
+	t.Parallel()
+
+	fs := newTwoVaultFs(t)
+	unlockerDir, c := newUnlockTestCLI(t, fs)
+
+	require.NoError(t, afero.WriteFile(fs, filepath.Join(unlockerDir, "priv.age"),
+		[]byte("damaged"), secret.FilePerms))
+
+	err := c.GetSecret(discardCmd(), "x")
+
+	require.NotErrorIs(t, err, secret.ErrWrongPassphrase)
+	require.ErrorContains(t, err, mnemonicAdvice)
 }
 
 // TestMoveUnlockFailureNamesVault checks the error of `secret move` into

internal/cli/unlockers.go

@@ -326,22 +326,25 @@ func (cli *Instance) printUnlockersJSON(
 		return fmt.Errorf("failed to marshal JSON: %w", err)
 	}
 
-	cli.cmd.Println(string(jsonBytes))
+	_, _ = fmt.Fprintln(cli.cmd.OutOrStdout(), string(jsonBytes))
 
 	return nil
 }
 
 // printUnlockersTable prints unlockers in a formatted table
 func (cli *Instance) printUnlockersTable(unlockers []UnlockerInfo) error {
+	out := cli.cmd.OutOrStdout()
+
 	if len(unlockers) == 0 {
-		cli.cmd.Println("No unlockers found in current vault.")
+		_, _ = fmt.Fprintln(out, "No unlockers found in current vault.")
-		cli.cmd.Println("Run 'secret unlocker add passphrase' to create one.")
+		_, _ = fmt.Fprintln(out, "Run 'secret unlocker add passphrase' to create one.")
 
 		return nil
 	}
 
-	cli.cmd.Printf("  %-40s %-12s %-20s %s\n", "UNLOCKER ID", "TYPE", "CREATED", "FLAGS")
+	_, _ = fmt.Fprintf(out, "  %-40s %-12s %-20s %s\n",
-	cli.cmd.Printf("  %-40s %-12s %-20s %s\n",
+		"UNLOCKER ID", "TYPE", "CREATED", "FLAGS")
+	_, _ = fmt.Fprintf(out, "  %-40s %-12s %-20s %s\n",
 		strings.Repeat("-", unlockerIDWidth), strings.Repeat("-", unlockerTypeWidth),
 		strings.Repeat("-", unlockerDateWidth), strings.Repeat("-", unlockerFlagsWidth))
 
@@ -356,7 +359,7 @@ func (cli *Instance) printUnlockersTable(unlockers []UnlockerInfo) error {
 			prefix = "* "
 		}
 
-		cli.cmd.Printf("%s%-40s %-12s %-20s %s\n",
+		_, _ = fmt.Fprintf(out, "%s%-40s %-12s %-20s %s\n",
 			prefix,
 			unlocker.ID,
 			unlocker.Type,
@@ -364,7 +367,7 @@ func (cli *Instance) printUnlockersTable(unlockers []UnlockerInfo) error {
 			flags)
 	}
 
-	cli.cmd.Printf("\nTotal: %d unlocker(s)\n", len(unlockers))
+	_, _ = fmt.Fprintf(out, "\nTotal: %d unlocker(s)\n", len(unlockers))
 
 	return nil
 }

internal/cli/vault.go

@@ -186,6 +186,8 @@ func (cli *Instance) ListVaults(cmd *cobra.Command, jsonOutput bool) error {
 		return err
 	}
 
+	out := cmd.OutOrStdout()
+
 	if jsonOutput { //nolint:nestif // Separate JSON and text output formatting logic
 		// Get current vault name for context
 		currentVault := ""
@@ -205,13 +207,13 @@ func (cli *Instance) ListVaults(cmd *cobra.Command, jsonOutput bool) error {
 			return err
 		}
 
-		cmd.Println(string(jsonBytes))
+		_, _ = fmt.Fprintln(out, string(jsonBytes))
 	} else {
 		// Text output
-		cmd.Println("Available vaults:")
+		_, _ = fmt.Fprintln(out, "Available vaults:")
 
 		if len(vaults) == 0 {
-			cmd.Println("  (none)")
+			_, _ = fmt.Fprintln(out, "  (none)")
 		} else {
 			// Try to get current vault for marking
 			currentVault := ""
@@ -223,9 +225,9 @@ func (cli *Instance) ListVaults(cmd *cobra.Command, jsonOutput bool) error {
 
 			for _, vaultName := range vaults {
 				if vaultName == currentVault {
-					cmd.Printf("  %s (current)\n", vaultName)
+					_, _ = fmt.Fprintf(out, "  %s (current)\n", vaultName)
 				} else {
-					cmd.Printf("  %s\n", vaultName)
+					_, _ = fmt.Fprintf(out, "  %s\n", vaultName)
 				}
 			}
 		}

internal/cli/version.go

@@ -167,7 +167,7 @@ func (cli *Instance) ListVersions(cmd *cobra.Command, secretName string) error {
 	}
 
 	if len(versions) == 0 {
-		cmd.Println("No versions found")
+		_, _ = fmt.Fprintln(cmd.OutOrStdout(), "No versions found")
 
 		return nil
 	}

internal/secret/passphraseunlocker.go

@@ -16,6 +16,10 @@ import (
 // empty. A passphrase unlocker that fails with it was not tried.
 var ErrPassphraseNotRead = errors.New("failed to read passphrase")
 
+// ErrWrongPassphrase is wrapped in the error of GetIdentity when the
+// passphrase does not decrypt the unlocker's private key.
+var ErrWrongPassphrase = errors.New("wrong passphrase")
+
 // PassphraseUnlocker represents a passphrase-protected unlocker
 type PassphraseUnlocker struct {
 	Directory  string
@@ -73,6 +77,12 @@ func (p *PassphraseUnlocker) GetIdentity() (*age.X25519Identity, error) {
 		Debug("Failed to decrypt unlocker private key",
 			"error", err, "unlocker_id", p.GetID())
 
+		// age says that no identity matched when the passphrase is wrong
+		var noMatch *age.NoIdentityMatchError
+		if errors.As(err, &noMatch) {
+			return nil, fmt.Errorf("%w for unlocker %s", ErrWrongPassphrase, p.GetID())
+		}
+
 		return nil, fmt.Errorf("failed to decrypt unlocker private key: %w", err)
 	}
 	defer privKeyBuffer.Destroy()

internal/vault/vault.go

@@ -291,10 +291,13 @@ func (v *Vault) unlockLongTermKey(
 // without a mnemonic records none, and without its metadata the key cannot
 // be derived. It is not added when the passphrase could not be read: the
 // unlocker was not tried, and adding one would need a passphrase read the
-// same way. Nor is it added when the current unlocker does not exist and the
+// same way. Nor is it added when the passphrase is wrong: the unlocker still
-// vault has others: the error already says to select one of them.
+// opens the vault with the right one. Nor is it added when the current
+// unlocker does not exist and the vault has others: the error already says
+// to select one of them.
 func (v *Vault) withMnemonicAdvice(err error) error {
 	if errors.Is(err, secret.ErrPassphraseNotRead) ||
+		errors.Is(err, secret.ErrWrongPassphrase) ||
 		errors.Is(err, ErrUnlockerNotFound) {
 		return err
 	}

internal/vault/vault_error_test.go

@@ -5,7 +5,6 @@ import (
 	"path/filepath"
 	"testing"
 
-	"filippo.io/age"
 	"github.com/awnumar/memguard"
 	"github.com/spf13/afero"
 	"github.com/stretchr/testify/assert"
@@ -140,9 +139,7 @@ func TestAddSecretForceWithWrongPassphraseChangesNothing(t *testing.T) {
 
 	err = vlt.AddSecret(testSecretName, second, true)
 
-	var noMatch *age.NoIdentityMatchError
+	require.ErrorIs(t, err, secret.ErrWrongPassphrase)
-
-	require.ErrorAs(t, err, &noMatch)
 	assert.Equal(t, before, dirContents(t, fs, secretDir))
 }