libsecret: Add secret_service_encode_dbus_secret() and opposite

Add secret_service_encode_dbus_secret() and
secret_service_decode_dbus_secret() functions for encoding
and decoding the Secret Service API DBus structs that carry
secrets on the wire.

These are not added to the stable or scripting APIs.

docs/reference/libsecret/libsecret-sections.txt

@@ -289,6 +289,8 @@ secret_service_read_alias_dbus_path_sync
 secret_service_set_alias_to_dbus_path
 secret_service_set_alias_to_dbus_path_finish
 secret_service_set_alias_to_dbus_path_sync
+secret_service_encode_dbus_secret
+secret_service_decode_dbus_secret
 </SECTION>
 
 <SECTION>

libsecret/secret-paths.c

@@ -2581,3 +2581,62 @@ secret_service_prompt_at_dbus_path_finish (SecretService *self,
 
 	return secret_service_prompt_finish (self, result, error);
 }
+
+/**
+ * secret_service_encode_dbus_secret:
+ * @service: the service
+ * @value: the secret value
+ *
+ * Encodes a #SecretValue into GVariant for use with the Secret Service
+ * DBus API.
+ *
+ * The resulting GVariant will have a <literal>(oayays)</literal> signature.
+ *
+ * A session must have already been established by the #SecretService.
+ *
+ * Returns: (transfer floating): the encoded secret
+ */
+GVariant *
+secret_service_encode_dbus_secret (SecretService *service,
+                                   SecretValue *value)
+{
+	SecretSession *session;
+
+	g_return_val_if_fail (service != NULL, NULL);
+	g_return_val_if_fail (value != NULL, NULL);
+
+	session = _secret_service_get_session (service);
+	g_return_val_if_fail (session != NULL, NULL);
+
+	return _secret_session_encode_secret (session, value);
+}
+
+/**
+ * secret_service_decode_dbus_secret:
+ * @service: the service
+ * @value: the encoded secret
+ *
+ * Decode a #SecretValue into GVariant received with the Secret Service
+ * DBus API.
+ *
+ * The GVariant should have a <literal>(oayays)</literal> signature.
+ *
+ * A session must have already been established by the #SecretService, and
+ * the encoded secret must be valid for that session.
+ *
+ * Returns: (transfer full): the decoded secret value
+ */
+SecretValue *
+secret_service_decode_dbus_secret (SecretService *service,
+                                   GVariant *value)
+{
+	SecretSession *session;
+
+	g_return_val_if_fail (service != NULL, NULL);
+	g_return_val_if_fail (value != NULL, NULL);
+
+	session = _secret_service_get_session (service);
+	g_return_val_if_fail (session != NULL, NULL);
+
+	return _secret_session_decode_secret (session, value);
+}

libsecret/secret-paths.h

@@ -272,6 +272,12 @@ gboolean            secret_service_set_alias_to_dbus_path_sync         (SecretSe
                                                                         GCancellable *cancellable,
                                                                         GError **error);
 
+GVariant *          secret_service_encode_dbus_secret                  (SecretService *service,
+                                                                        SecretValue *value);
+
+SecretValue *       secret_service_decode_dbus_secret                  (SecretService *service,
+                                                                        GVariant *value);
+
 G_END_DECLS
 
 #endif /* __SECRET_SERVICE_H___ */

libsecret/test-paths.c

@@ -710,6 +710,33 @@ test_set_alias_path (Test *test,
 	g_assert (path == NULL);
 }
 
+static void
+test_encode_decode_secret (Test *test,
+                           gconstpointer unused)
+{
+	GVariant *variant;
+	SecretValue *value;
+	SecretValue *decoded;
+	GError *error = NULL;
+
+	value = secret_value_new ("zerogjuggs", -1, "text/plain");
+
+	secret_service_ensure_session_sync (test->service, NULL, &error);
+	g_assert_no_error (error);
+
+	variant = secret_service_encode_dbus_secret (test->service, value);
+	g_assert (variant != NULL);
+	g_assert_cmpstr (g_variant_get_type_string (variant), ==, "(oayays)");
+	secret_value_unref (value);
+
+	decoded = secret_service_decode_dbus_secret (test->service, variant);
+	g_assert (variant != NULL);
+	g_variant_unref (variant);
+
+	g_assert_cmpstr (secret_value_get_text (decoded), ==, "zerogjuggs");
+	secret_value_unref (decoded);
+}
+
 int
 main (int argc, char **argv)
 {
@@ -746,5 +773,7 @@ main (int argc, char **argv)
 
 	g_test_add ("/service/set-alias-path", Test, "mock-service-normal.py", setup, test_set_alias_path, teardown);
 
+	g_test_add ("/service/encode-decode-secret", Test, "mock-service-normal.py", setup, test_encode_decode_secret, teardown);
+
 	return egg_tests_run_with_loop ();
 }