Merge pull request #31661 from nextcloud/enh/user_ldap-add-command-to-unmap-groups

Add ldap:reset-group command to unmap groups from LDAP

5 files changed, 162 insertions, 21 deletions

diff --git a/apps/user_ldap/lib/Command/ResetGroup.php b/apps/user_ldap/lib/Command/ResetGroup.php
new file mode 100644
index 00000000000..f3c3019f919
--- /dev/null
+++ b/apps/user_ldap/lib/Command/ResetGroup.php
@@ -0,0 +1,111 @@
+<?php
+/**
+ * @copyright Copyright (c) 2021 Arthur Schiwon <blizzz@arthur-schiwon.de>
+ *
+ * @author Arthur Schiwon <blizzz@arthur-schiwon.de>
+ * @author Côme Chilliet <come.chilliet@nextcloud.com>
+ *
+ * @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\Group_Proxy;
+use OCA\User_LDAP\GroupPluginManager;
+use OCP\IGroup;
+use OCP\IGroupManager;
+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 ResetGroup extends Command {
+	private IGroupManager $groupManager;
+	private GroupPluginManager $pluginManager;
+	private Group_Proxy $backend;
+
+	public function __construct(
+		IGroupManager $groupManager,
+		GroupPluginManager $pluginManager,
+		Group_Proxy $backend
+	) {
+		$this->groupManager = $groupManager;
+		$this->pluginManager = $pluginManager;
+		$this->backend = $backend;
+		parent::__construct();
+	}
+
+	protected function configure(): void {
+		$this
+			->setName('ldap:reset-group')
+			->setDescription('deletes an LDAP group independent of the group state in the LDAP')
+			->addArgument(
+				'gid',
+				InputArgument::REQUIRED,
+				'the group name as used in Nextcloud'
+			)
+			->addOption(
+				'yes',
+				'y',
+				InputOption::VALUE_NONE,
+				'do not ask for confirmation'
+			);
+	}
+
+	protected function execute(InputInterface $input, OutputInterface $output): int {
+		try {
+			$gid = $input->getArgument('gid');
+			$group = $this->groupManager->get($gid);
+			if (!$group instanceof IGroup) {
+				throw new \Exception('Group not found');
+			}
+			$backends = $group->getBackendNames();
+			if (!in_array('LDAP', $backends)) {
+				throw new \Exception('The given group is not a recognized LDAP group.');
+			}
+			if ($input->getOption('yes') === false) {
+				/** @var QuestionHelper $helper */
+				$helper = $this->getHelper('question');
+				$q = new Question('Delete all local data of this group (y|N)? ');
+				$input->setOption('yes', $helper->ask($input, $output, $q) === 'y');
+			}
+			if ($input->getOption('yes') !== true) {
+				throw new \Exception('Reset cancelled by operator');
+			}
+
+			// Disable real deletion if a plugin supports it
+			$pluginManagerSuppressed = $this->pluginManager->setSuppressDeletion(true);
+			// Bypass groupExists test to force mapping deletion
+			$this->backend->getLDAPAccess($gid)->connection->writeToCache('groupExists' . $gid, false);
+			echo "calling delete $gid\n";
+			if ($group->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 group</error>');
+		return 2;
+	}
+}
diff --git a/apps/user_ldap/lib/GroupPluginManager.php b/apps/user_ldap/lib/GroupPluginManager.php
index d23e9d4d443..5999409cdba 100644
--- a/apps/user_ldap/lib/GroupPluginManager.php
+++ b/apps/user_ldap/lib/GroupPluginManager.php
@@ -26,9 +26,10 @@ namespace OCA\User_LDAP;
 use OCP\GroupInterface;
 
 class GroupPluginManager {
-	private $respondToActions = 0;
+	private int $respondToActions = 0;
 
-	private $which = [
+	/** @var array<int, ?ILDAPGroupPlugin> */
+	private array $which = [
 		GroupInterface::CREATE_GROUP => null,
 		GroupInterface::DELETE_GROUP => null,
 		GroupInterface::ADD_TO_GROUP => null,
@@ -37,6 +38,8 @@ class GroupPluginManager {
 		GroupInterface::GROUP_DETAILS => null
 	];
 
+	private bool $suppressDeletion = false;
+
 	/**
 	 * @return int All implemented actions
 	 */
@@ -84,16 +87,31 @@ class GroupPluginManager {
 		throw new \Exception('No plugin implements createGroup in this LDAP Backend.');
 	}
 
+	public function canDeleteGroup(): bool {
+		return !$this->suppressDeletion && $this->implementsActions(GroupInterface::DELETE_GROUP);
+	}
+
+	/**
+	 * @return bool – the value before the change
+	 */
+	public function setSuppressDeletion(bool $value): bool {
+		$old = $this->suppressDeletion;
+		$this->suppressDeletion = $value;
+		return $old;
+	}
+
 	/**
 	 * Delete a group
-	 * @param string $gid Group Id of the group to delete
-	 * @return bool
+	 *
 	 * @throws \Exception
 	 */
-	public function deleteGroup($gid) {
+	public function deleteGroup(string $gid): bool {
 		$plugin = $this->which[GroupInterface::DELETE_GROUP];
 
 		if ($plugin) {
+			if ($this->suppressDeletion) {
+				return false;
+			}
 			return $plugin->deleteGroup($gid);
 		}
 		throw new \Exception('No plugin implements deleteGroup in this LDAP Backend.');
diff --git a/apps/user_ldap/lib/Group_LDAP.php b/apps/user_ldap/lib/Group_LDAP.php
index 766b77bf521..f9d9b061743 100644
--- a/apps/user_ldap/lib/Group_LDAP.php
+++ b/apps/user_ldap/lib/Group_LDAP.php
@@ -48,10 +48,11 @@ use OC;
 use OC\Cache\CappedMemoryCache;
 use OC\ServerNotAvailableException;
 use OCP\Group\Backend\IGetDisplayNameBackend;
+use OCP\Group\Backend\IDeleteGroupBackend;
 use OCP\GroupInterface;
 use Psr\Log\LoggerInterface;
 
-class Group_LDAP extends BackendUtility implements GroupInterface, IGroupLDAP, IGetDisplayNameBackend {
+class Group_LDAP extends BackendUtility implements GroupInterface, IGroupLDAP, IGetDisplayNameBackend, IDeleteGroupBackend {
 	protected $enabled = false;
 
 	/** @var string[][] $cachedGroupMembers array of users with gid as key */
@@ -1204,6 +1205,7 @@ class Group_LDAP extends BackendUtility implements GroupInterface, IGroupLDAP, I
 	 */
 	public function implementsActions($actions) {
 		return (bool)((GroupInterface::COUNT_USERS |
+				GroupInterface::DELETE_GROUP |
 				$this->groupPluginManager->getImplementedActions()) & $actions);
 	}
 
@@ -1249,19 +1251,32 @@ class Group_LDAP extends BackendUtility implements GroupInterface, IGroupLDAP, I
 	 * delete a group
 	 *
 	 * @param string $gid gid of the group to delete
-	 * @return bool
 	 * @throws Exception
 	 */
-	public function deleteGroup($gid) {
-		if ($this->groupPluginManager->implementsActions(GroupInterface::DELETE_GROUP)) {
+	public function deleteGroup(string $gid): bool {
+		if ($this->groupPluginManager->canDeleteGroup()) {
 			if ($ret = $this->groupPluginManager->deleteGroup($gid)) {
-				#delete group in nextcloud internal db
+				// Delete group in nextcloud internal db
 				$this->access->getGroupMapper()->unmap($gid);
 				$this->access->connection->writeToCache("groupExists" . $gid, false);
 			}
 			return $ret;
 		}
-		throw new Exception('Could not delete group in LDAP backend.');
+
+		// Getting dn, if false the group is not mapped
+		$dn = $this->access->groupname2dn($gid);
+		if (!$dn) {
+			throw new Exception('Could not delete unknown group '.$gid.' in LDAP backend.');
+		}
+
+		if (!$this->groupExists($gid)) {
+			// The group does not exist in the LDAP, remove the mapping
+			$this->access->getGroupMapper()->unmap($gid);
+			$this->access->connection->writeToCache("groupExists" . $gid, false);
+			return true;
+		}
+
+		throw new Exception('Could not delete existing group '.$gid.' in LDAP backend.');
 	}
 
 	/**
diff --git a/apps/user_ldap/lib/Group_Proxy.php b/apps/user_ldap/lib/Group_Proxy.php
index 92a9041949e..ea2fcce679c 100644
--- a/apps/user_ldap/lib/Group_Proxy.php
+++ b/apps/user_ldap/lib/Group_Proxy.php
@@ -28,10 +28,11 @@
  */
 namespace OCA\User_LDAP;
 
-use OCP\Group\Backend\INamedBackend;
+use OCP\Group\Backend\IDeleteGroupBackend;
 use OCP\Group\Backend\IGetDisplayNameBackend;
+use OCP\Group\Backend\INamedBackend;
 
-class Group_Proxy extends Proxy implements \OCP\GroupInterface, IGroupLDAP, IGetDisplayNameBackend, INamedBackend {
+class Group_Proxy extends Proxy implements \OCP\GroupInterface, IGroupLDAP, IGetDisplayNameBackend, INamedBackend, IDeleteGroupBackend {
 	private $backends = [];
 	private $refBackend = null;
 
@@ -171,11 +172,8 @@ class Group_Proxy extends Proxy implements \OCP\GroupInterface, IGroupLDAP, IGet
 
 	/**
 	 * delete a group
-	 *
-	 * @param string $gid gid of the group to delete
-	 * @return bool
 	 */
-	public function deleteGroup($gid) {
+	public function deleteGroup(string $gid): bool {
 		return $this->handleRequest(
 			$gid, 'deleteGroup', [$gid]);
 	}
diff --git a/apps/user_ldap/lib/UserPluginManager.php b/apps/user_ldap/lib/UserPluginManager.php
index 035b7952dce..748a210cf60 100644
--- a/apps/user_ldap/lib/UserPluginManager.php
+++ b/apps/user_ldap/lib/UserPluginManager.php
@@ -28,9 +28,9 @@ namespace OCA\User_LDAP;
 use OC\User\Backend;
 
 class UserPluginManager {
-	private $respondToActions = 0;
+	private int $respondToActions = 0;
 
-	private $which = [
+	private array $which = [
 		Backend::CREATE_USER => null,
 		Backend::SET_PASSWORD => null,
 		Backend::GET_HOME => null,
@@ -41,8 +41,7 @@ class UserPluginManager {
 		'deleteUser' => null
 	];
 
-	/** @var bool */
-	private $suppressDeletion = false;
+	private bool $suppressDeletion = false;
 
 	/**
 	 * @return int All implemented actions, except for 'deleteUser'