adds ldap user:reset command

- allows to delete data of existing LDAP users, which otherwise is safe
  guarded
- ensures that the user is not being deleted on LDAP through a plugin

Signed-off-by: Arthur Schiwon <blizzz@arthur-schiwon.de>

2 files changed, 129 insertions, 3 deletions

diff --git a/apps/user_ldap/lib/Command/ResetUser.php b/apps/user_ldap/lib/Command/ResetUser.php
new file mode 100644
index 00000000000..2daccdb6dcc
--- /dev/null
+++ b/apps/user_ldap/lib/Command/ResetUser.php
@@ -0,0 +1,112 @@
+<?php
+/**
+ * @copyright Copyright (c) 2021 Arthur Schiwon <blizzz@arthur-schiwon.de>
+ *
+ * @author Arthur Schiwon <blizzz@arthur-schiwon.de>
+ *
+ * @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 OCA\User_LDAP\Command;
+
+use OCA\User_LDAP\User\DeletedUsersIndex;
+use OCA\User_LDAP\User_Proxy;
+use OCA\User_LDAP\UserPluginManager;
+use OCP\IUser;
+use OCP\IUserManager;
+use Symfony\Component\Console\Command\Command;
+use Symfony\Component\Console\Helper\QuestionHelper;
+use Symfony\Component\Console\Input\InputArgument;
+use Symfony\Component\Console\Input\InputInterface;
+use Symfony\Component\Console\Input\InputOption;
+use Symfony\Component\Console\Output\OutputInterface;
+use Symfony\Component\Console\Question\Question;
+
+class ResetUser extends Command {
+	/** @var DeletedUsersIndex */
+	protected $dui;
+	/** @var IUserManager */
+	private $userManager;
+	/** @var UserPluginManager */
+	private $pluginManager;
+
+	public function __construct(
+		DeletedUsersIndex $dui,
+		IUserManager $userManager,
+		UserPluginManager $pluginManager
+	) {
+		$this->dui = $dui;
+		$this->userManager = $userManager;
+		$this->pluginManager = $pluginManager;
+		parent::__construct();
+	}
+
+	protected function configure() {
+		$this
+			->setName('ldap:reset-user')
+			->setDescription('deletes an LDAP user independent of the user state')
+			->addArgument(
+				'uid',
+				InputArgument::REQUIRED,
+				'the user id as used in Nextcloud'
+			)
+			->addOption(
+				'yes',
+				'y',
+				InputOption::VALUE_NONE,
+				'do not ask for confirmation'
+			);
+	}
+
+	protected function execute(InputInterface $input, OutputInterface $output): int {
+		try {
+			$uid = $input->getArgument('uid');
+			$user = $this->userManager->get($uid);
+			if (!$user instanceof IUser) {
+				throw new \Exception('User not found');
+			}
+			$backend = $user->getBackend();
+			if (!$backend instanceof User_Proxy) {
+				throw new \Exception('The given user is not a recognized LDAP user.');
+			}
+			if ($input->getOption('yes') === false) {
+				/** @var QuestionHelper $helper */
+				$helper = $this->getHelper('question');
+				$q = new Question('Delete all local data of this user (y|N)? ');
+				$input->setOption('yes', $helper->ask($input, $output, $q) === 'y');
+			}
+			if ($input->getOption('yes') !== true) {
+				throw new \Exception('Reset cancelled by operator');
+			}
+
+			$this->dui->markUser($uid);
+			$pluginManagerSuppressed = $this->pluginManager->setSuppressDeletion(true);
+			if ($user->delete()) {
+				$this->pluginManager->setSuppressDeletion($pluginManagerSuppressed);
+				return 0;
+			}
+		} catch (\Throwable $e) {
+			if (isset($pluginManagerSuppressed)) {
+				$this->pluginManager->setSuppressDeletion($pluginManagerSuppressed);
+			}
+			$output->writeln('<error>' . $e->getMessage() . '</error>');
+			return 1;
+		}
+		$output->writeln('<error>Error while resetting user</error>');
+		return 2;
+	}
+}
diff --git a/apps/user_ldap/lib/UserPluginManager.php b/apps/user_ldap/lib/UserPluginManager.php
index 2d99d887604..fdc08d3d38b 100644
--- a/apps/user_ldap/lib/UserPluginManager.php
+++ b/apps/user_ldap/lib/UserPluginManager.php
@@ -28,8 +28,6 @@ namespace OCA\User_LDAP;
 use OC\User\Backend;
 
 class UserPluginManager {
-	public $test = false;
-
 	private $respondToActions = 0;
 
 	private $which = [
@@ -43,6 +41,9 @@ class UserPluginManager {
 		'deleteUser' => null
 	];
 
+	/** @var bool */
+	private $suppressDeletion = false;
+
 	/**
 	 * @return int All implemented actions, except for 'deleteUser'
 	 */
@@ -192,7 +193,7 @@ class UserPluginManager {
 	 * @return bool
 	 */
 	public function canDeleteUser() {
-		return $this->which['deleteUser'] !== null;
+		return !$this->suppressDeletion && $this->which['deleteUser'] !== null;
 	}
 
 	/**
@@ -203,8 +204,21 @@ class UserPluginManager {
 	public function deleteUser($uid) {
 		$plugin = $this->which['deleteUser'];
 		if ($plugin) {
+			if ($this->suppressDeletion) {
+				return false;
+			}
 			return $plugin->deleteUser($uid);
 		}
 		throw new \Exception('No plugin implements deleteUser in this LDAP Backend.');
 	}
+
+	/**
+	 * @param bool $value
+	 * @return bool – the value before the change
+	 */
+	public function setSuppressDeletion(bool $value): bool {
+		$old = $this->suppressDeletion;
+		$this->suppressDeletion = $value;
+		return $old;
+	}
 }