Make 2FA providers stateful

This adds persistence to the Nextcloud server 2FA logic so that the server
knows which 2FA providers are enabled for a specific user at any time, even
when the provider is not available.

The `IStatefulProvider` interface was added as tagging interface for providers
that are compatible with this new API.

Signed-off-by: Christoph Wurst <christoph@winzerhof-wurst.at>

1 files changed, 65 insertions, 0 deletions

diff --git a/lib/public/Authentication/TwoFactorAuth/IRegistry.php b/lib/public/Authentication/TwoFactorAuth/IRegistry.php
new file mode 100644
index 00000000000..5013892d402
--- /dev/null
+++ b/lib/public/Authentication/TwoFactorAuth/IRegistry.php
@@ -0,0 +1,65 @@
+<?php
+
+declare(strict_types = 1);
+
+/**
+ * @copyright 2018 Christoph Wurst <christoph@winzerhof-wurst.at>
+ *
+ * @author 2018 Christoph Wurst <christoph@winzerhof-wurst.at>
+ *
+ * @license GNU AGPL version 3 or any later version
+ *
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU Affero General Public License as
+ * published by the Free Software Foundation, either version 3 of the
+ * License, or (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU Affero General Public License for more details.
+ *
+ * You should have received a copy of the GNU Affero General Public License
+ * along with this program.  If not, see <http://www.gnu.org/licenses/>.
+ *
+ */
+
+namespace OCP\Authentication\TwoFactorAuth;
+
+use OCP\IUser;
+
+/**
+ * Nextcloud 2FA provider registry for stateful 2FA providers
+ * 
+ * This service keeps track of which providers are currently active for a specific
+ * user. Stateful 2FA providers (IStatefulProvider) must use this service to save
+ * their enabled/disabled state.
+ *
+ * @since 14.0.0
+ */
+interface IRegistry {
+
+	/**
+	 * Get a key-value map of providers and their enabled/disabled state for
+	 * the given user.
+	 *
+	 * @since 14.0.0
+	 * @return string[] where the array key is the provider ID (string) and the
+	 *                  value is the enabled state (bool)
+	 */
+	public function getProviderStates(IUser $user): array;
+
+	/**
+	 * Enable the given 2FA provider for the given user
+	 *
+	 * @since 14.0.0
+	 */
+	public function enableProviderFor(IProvider $provider, IUser $user);
+
+	/**
+	 * Disable the given 2FA provider for the given user
+	 *
+	 * @since 14.0.0
+	 */
+	public function disableProviderFor(IProvider $provider, IUser $user);
+}