Merge pull request 'Validate secret name in GetSecretVersion to prevent path traversal (closes #13)' (#15) from clawbot/secret:fix/issue-13 into main

Reviewed-on: #15

internal/vault/path_traversal_test.go

@@ -0,0 +1,96 @@
+package vault
+
+import (
+	"testing"
+
+	"git.eeqj.de/sneak/secret/internal/secret"
+	"github.com/awnumar/memguard"
+	"github.com/spf13/afero"
+	"github.com/stretchr/testify/assert"
+	"github.com/stretchr/testify/require"
+)
+
+// TestGetSecretVersionRejectsPathTraversal verifies that GetSecretVersion
+// validates the secret name and rejects path traversal attempts.
+// This is a regression test for https://git.eeqj.de/sneak/secret/issues/13
+func TestGetSecretVersionRejectsPathTraversal(t *testing.T) {
+	testMnemonic := "abandon abandon abandon abandon abandon abandon abandon abandon abandon abandon abandon about"
+	t.Setenv(secret.EnvMnemonic, testMnemonic)
+	t.Setenv(secret.EnvUnlockPassphrase, "test-passphrase")
+
+	fs := afero.NewMemMapFs()
+	stateDir := "/test/state"
+
+	vlt, err := CreateVault(fs, stateDir, "test-vault")
+	require.NoError(t, err)
+
+	// Add a legitimate secret so the vault is set up
+	value := memguard.NewBufferFromBytes([]byte("legitimate-secret"))
+	err = vlt.AddSecret("legit", value, false)
+	require.NoError(t, err)
+
+	// These names contain path traversal and should be rejected
+	maliciousNames := []string{
+		"../../../etc/passwd",
+		"..%2f..%2fetc/passwd",
+		".secret",
+		"../sibling-vault/secrets.d/target",
+		"foo/../bar",
+		"a/../../etc/passwd",
+	}
+
+	for _, name := range maliciousNames {
+		t.Run(name, func(t *testing.T) {
+			_, err := vlt.GetSecretVersion(name, "")
+			assert.Error(t, err, "GetSecretVersion should reject malicious name: %s", name)
+			assert.Contains(t, err.Error(), "invalid secret name",
+				"error should indicate invalid name for: %s", name)
+		})
+	}
+}
+
+// TestGetSecretRejectsPathTraversal verifies GetSecret (which calls GetSecretVersion)
+// also rejects path traversal names.
+func TestGetSecretRejectsPathTraversal(t *testing.T) {
+	testMnemonic := "abandon abandon abandon abandon abandon abandon abandon abandon abandon abandon abandon about"
+	t.Setenv(secret.EnvMnemonic, testMnemonic)
+	t.Setenv(secret.EnvUnlockPassphrase, "test-passphrase")
+
+	fs := afero.NewMemMapFs()
+	stateDir := "/test/state"
+
+	vlt, err := CreateVault(fs, stateDir, "test-vault")
+	require.NoError(t, err)
+
+	_, err = vlt.GetSecret("../../../etc/passwd")
+	assert.Error(t, err)
+	assert.Contains(t, err.Error(), "invalid secret name")
+}
+
+// TestGetSecretObjectRejectsPathTraversal verifies GetSecretObject
+// also validates names and rejects path traversal attempts.
+func TestGetSecretObjectRejectsPathTraversal(t *testing.T) {
+	testMnemonic := "abandon abandon abandon abandon abandon abandon abandon abandon abandon abandon abandon about"
+	t.Setenv(secret.EnvMnemonic, testMnemonic)
+	t.Setenv(secret.EnvUnlockPassphrase, "test-passphrase")
+
+	fs := afero.NewMemMapFs()
+	stateDir := "/test/state"
+
+	vlt, err := CreateVault(fs, stateDir, "test-vault")
+	require.NoError(t, err)
+
+	maliciousNames := []string{
+		"../../../etc/passwd",
+		"foo/../bar",
+		"a/../../etc/passwd",
+	}
+
+	for _, name := range maliciousNames {
+		t.Run(name, func(t *testing.T) {
+			_, err := vlt.GetSecretObject(name)
+			assert.Error(t, err, "GetSecretObject should reject: %s", name)
+			assert.Contains(t, err.Error(), "invalid secret name")
+		})
+	}
+}

internal/vault/secrets.go

@@ -92,6 +92,13 @@ func isValidSecretName(name string) bool {
 		return false
 	}
 
+	// Check for path traversal via ".." components
+	for _, part := range strings.Split(name, "/") {
+		if part == ".." {
+			return false
+		}
+	}
+
 	// Check the basic pattern
 	matched, _ := regexp.MatchString(`^[a-z0-9\.\-\_\/]+$`, name)
 
@@ -319,6 +326,13 @@ func (v *Vault) GetSecretVersion(name string, version string) ([]byte, error) {
 		slog.String("version", version),
 	)
 
+	// Validate secret name to prevent path traversal
+	if !isValidSecretName(name) {
+		secret.Debug("Invalid secret name provided", "secret_name", name)
+
+		return nil, fmt.Errorf("invalid secret name '%s': must match pattern [a-z0-9.\\-_/]+", name)
+	}
+
 	// Get vault directory
 	vaultDir, err := v.GetDirectory()
 	if err != nil {
@@ -454,6 +468,10 @@ func (v *Vault) UnlockVault() (*age.X25519Identity, error) {
 
 // GetSecretObject retrieves a Secret object with metadata loaded from this vault
 func (v *Vault) GetSecretObject(name string) (*secret.Secret, error) {
+	if !isValidSecretName(name) {
+		return nil, fmt.Errorf("invalid secret name: %s", name)
+	}
+
 	// First check if the secret exists by checking for the metadata file
 	vaultDir, err := v.GetDirectory()
 	if err != nil {