Allow DAV Object properties

The current implementation only saves them as string. It seems they can
be more complex than that, and that objects were saved directly.

You may find such objects saved in some production databases by
executing:
```sql
SELECT * from oc_properties where propertyvalue = 'Object';
```

This commit adds a repair job to clean all of these "broken" properties
values, adds a new database column to save the type of the property, and
handles converting from and to correct values.

Implementation is very similar to SabreDAV's own PDO backend: https://github.com/nextcloud/3rdparty/blob/4921806dfb1c5c309eac60195ed34e2749baf3c1/sabre/dav/lib/DAV/PropertyStorage/Backend/PDO.php

Signed-off-by: Thomas Citharel <tcit@tcit.fr>

6 files changed, 187 insertions, 13 deletions

diff --git a/apps/dav/appinfo/info.xml b/apps/dav/appinfo/info.xml
index 10f78d8332a..deb99b1c33b 100644
--- a/apps/dav/appinfo/info.xml
+++ b/apps/dav/appinfo/info.xml
@@ -5,7 +5,7 @@
 	<name>WebDAV</name>
 	<summary>WebDAV endpoint</summary>
 	<description>WebDAV endpoint</description>
-	<version>1.23.0</version>
+	<version>1.24.0</version>
 	<licence>agpl</licence>
 	<author>owncloud.org</author>
 	<namespace>DAV</namespace>
@@ -39,6 +39,7 @@
 			<step>OCA\DAV\Migration\RemoveOrphanEventsAndContacts</step>
 			<step>OCA\DAV\Migration\RemoveClassifiedEventActivity</step>
 			<step>OCA\DAV\Migration\RemoveDeletedUsersCalendarSubscriptions</step>
+			<step>OCA\DAV\Migration\RemoveObjectProperties</step>
 		</post-migration>
 		<live-migration>
 			<step>OCA\DAV\Migration\ChunkCleanup</step>
diff --git a/apps/dav/composer/composer/autoload_classmap.php b/apps/dav/composer/composer/autoload_classmap.php
index 5f7815a9bfc..47572dcb70a 100644
--- a/apps/dav/composer/composer/autoload_classmap.php
+++ b/apps/dav/composer/composer/autoload_classmap.php
@@ -252,6 +252,7 @@ return array(
     'OCA\\DAV\\Migration\\RegisterBuildReminderIndexBackgroundJob' => $baseDir . '/../lib/Migration/RegisterBuildReminderIndexBackgroundJob.php',
     'OCA\\DAV\\Migration\\RemoveClassifiedEventActivity' => $baseDir . '/../lib/Migration/RemoveClassifiedEventActivity.php',
     'OCA\\DAV\\Migration\\RemoveDeletedUsersCalendarSubscriptions' => $baseDir . '/../lib/Migration/RemoveDeletedUsersCalendarSubscriptions.php',
+    'OCA\\DAV\\Migration\\RemoveObjectProperties' => $baseDir . '/../lib/Migration/RemoveObjectProperties.php',
     'OCA\\DAV\\Migration\\RemoveOrphanEventsAndContacts' => $baseDir . '/../lib/Migration/RemoveOrphanEventsAndContacts.php',
     'OCA\\DAV\\Migration\\Version1004Date20170825134824' => $baseDir . '/../lib/Migration/Version1004Date20170825134824.php',
     'OCA\\DAV\\Migration\\Version1004Date20170919104507' => $baseDir . '/../lib/Migration/Version1004Date20170919104507.php',
@@ -273,6 +274,7 @@ return array(
     'OCA\\DAV\\Migration\\Version1016Date20201109085907' => $baseDir . '/../lib/Migration/Version1016Date20201109085907.php',
     'OCA\\DAV\\Migration\\Version1017Date20210216083742' => $baseDir . '/../lib/Migration/Version1017Date20210216083742.php',
     'OCA\\DAV\\Migration\\Version1018Date20210312100735' => $baseDir . '/../lib/Migration/Version1018Date20210312100735.php',
+    'OCA\\DAV\\Migration\\Version1024Date20211221144219' => $baseDir . '/../lib/Migration/Version1024Date20211221144219.php',
     'OCA\\DAV\\Profiler\\ProfilerPlugin' => $baseDir . '/../lib/Profiler/ProfilerPlugin.php',
     'OCA\\DAV\\Provisioning\\Apple\\AppleProvisioningNode' => $baseDir . '/../lib/Provisioning/Apple/AppleProvisioningNode.php',
     'OCA\\DAV\\Provisioning\\Apple\\AppleProvisioningPlugin' => $baseDir . '/../lib/Provisioning/Apple/AppleProvisioningPlugin.php',
diff --git a/apps/dav/composer/composer/autoload_static.php b/apps/dav/composer/composer/autoload_static.php
index 1f57b8b043a..b3e27d1bf72 100644
--- a/apps/dav/composer/composer/autoload_static.php
+++ b/apps/dav/composer/composer/autoload_static.php
@@ -267,6 +267,7 @@ class ComposerStaticInitDAV
         'OCA\\DAV\\Migration\\RegisterBuildReminderIndexBackgroundJob' => __DIR__ . '/..' . '/../lib/Migration/RegisterBuildReminderIndexBackgroundJob.php',
         'OCA\\DAV\\Migration\\RemoveClassifiedEventActivity' => __DIR__ . '/..' . '/../lib/Migration/RemoveClassifiedEventActivity.php',
         'OCA\\DAV\\Migration\\RemoveDeletedUsersCalendarSubscriptions' => __DIR__ . '/..' . '/../lib/Migration/RemoveDeletedUsersCalendarSubscriptions.php',
+        'OCA\\DAV\\Migration\\RemoveObjectProperties' => __DIR__ . '/..' . '/../lib/Migration/RemoveObjectProperties.php',
         'OCA\\DAV\\Migration\\RemoveOrphanEventsAndContacts' => __DIR__ . '/..' . '/../lib/Migration/RemoveOrphanEventsAndContacts.php',
         'OCA\\DAV\\Migration\\Version1004Date20170825134824' => __DIR__ . '/..' . '/../lib/Migration/Version1004Date20170825134824.php',
         'OCA\\DAV\\Migration\\Version1004Date20170919104507' => __DIR__ . '/..' . '/../lib/Migration/Version1004Date20170919104507.php',
@@ -288,6 +289,7 @@ class ComposerStaticInitDAV
         'OCA\\DAV\\Migration\\Version1016Date20201109085907' => __DIR__ . '/..' . '/../lib/Migration/Version1016Date20201109085907.php',
         'OCA\\DAV\\Migration\\Version1017Date20210216083742' => __DIR__ . '/..' . '/../lib/Migration/Version1017Date20210216083742.php',
         'OCA\\DAV\\Migration\\Version1018Date20210312100735' => __DIR__ . '/..' . '/../lib/Migration/Version1018Date20210312100735.php',
+        'OCA\\DAV\\Migration\\Version1024Date20211221144219' => __DIR__ . '/..' . '/../lib/Migration/Version1024Date20211221144219.php',
         'OCA\\DAV\\Profiler\\ProfilerPlugin' => __DIR__ . '/..' . '/../lib/Profiler/ProfilerPlugin.php',
         'OCA\\DAV\\Provisioning\\Apple\\AppleProvisioningNode' => __DIR__ . '/..' . '/../lib/Provisioning/Apple/AppleProvisioningNode.php',
         'OCA\\DAV\\Provisioning\\Apple\\AppleProvisioningPlugin' => __DIR__ . '/..' . '/../lib/Provisioning/Apple/AppleProvisioningPlugin.php',
diff --git a/apps/dav/lib/DAV/CustomPropertiesBackend.php b/apps/dav/lib/DAV/CustomPropertiesBackend.php
index acee65cd00d..bd09ac2e4e6 100644
--- a/apps/dav/lib/DAV/CustomPropertiesBackend.php
+++ b/apps/dav/lib/DAV/CustomPropertiesBackend.php
@@ -31,6 +31,7 @@ use Sabre\DAV\PropertyStorage\Backend\BackendInterface;
 use Sabre\DAV\PropFind;
 use Sabre\DAV\PropPatch;
 use Sabre\DAV\Tree;
+use Sabre\DAV\Xml\Property\Complex;
 use function array_intersect;
 
 class CustomPropertiesBackend implements BackendInterface {
@@ -39,6 +40,21 @@ class CustomPropertiesBackend implements BackendInterface {
 	private const TABLE_NAME = 'properties';
 
 	/**
+	 * Value is stored as string.
+	 */
+	public const PROPERTY_TYPE_STRING = 1;
+
+	/**
+	 * Value is stored as XML fragment.
+	 */
+	public const PROPERTY_TYPE_XML = 2;
+
+	/**
+	 * Value is stored as a property object.
+	 */
+	public const PROPERTY_TYPE_OBJECT = 3;
+
+	/**
 	 * Ignored properties
 	 *
 	 * @var string[]
@@ -239,7 +255,7 @@ class CustomPropertiesBackend implements BackendInterface {
 		$result = $qb->executeQuery();
 		$props = [];
 		while ($row = $result->fetch()) {
-			$props[$row['propertyname']] = $row['propertyvalue'];
+			$props[$row['propertyname']] = $this->decodeValueFromDatabase($row['propertyvalue'], $row['valuetype']);
 		}
 		$result->closeCursor();
 		return $props;
@@ -282,7 +298,7 @@ class CustomPropertiesBackend implements BackendInterface {
 
 		$props = [];
 		while ($row = $result->fetch()) {
-			$props[$row['propertyname']] = $row['propertyvalue'];
+			$props[$row['propertyname']] = $this->decodeValueFromDatabase($row['propertyvalue'], $row['valuetype']);
 		}
 
 		$result->closeCursor();
@@ -304,9 +320,9 @@ class CustomPropertiesBackend implements BackendInterface {
 			' WHERE `userid` = ? AND `propertypath` = ? AND `propertyname` = ?';
 
 		$insertStatement = 'INSERT INTO `*PREFIX*properties`' .
-			' (`userid`,`propertypath`,`propertyname`,`propertyvalue`) VALUES(?,?,?,?)';
+			' (`userid`,`propertypath`,`propertyname`,`propertyvalue`, `valuetype`) VALUES(?,?,?,?,?)';
 
-		$updateStatement = 'UPDATE `*PREFIX*properties` SET `propertyvalue` = ?' .
+		$updateStatement = 'UPDATE `*PREFIX*properties` SET `propertyvalue` = ?, `valuetype` = ?' .
 			' WHERE `userid` = ? AND `propertypath` = ? AND `propertyname` = ?';
 
 		// TODO: use "insert or update" strategy ?
@@ -325,24 +341,22 @@ class CustomPropertiesBackend implements BackendInterface {
 					);
 				}
 			} else {
-				if ($propertyValue instanceOf \Sabre\DAV\Xml\Property\Complex) {
-					$propertyValue = $propertyValue->getXml();
-				} elseif (!is_string($propertyValue)) {
-					$propertyValue = (string)$propertyValue;
-				}
+				[$value, $valueType] = $this->encodeValueForDatabase($propertyValue);
 				if (!array_key_exists($propertyName, $existing)) {
 					$this->connection->executeUpdate($insertStatement,
 						[
 							$this->user->getUID(),
 							$this->formatPath($path),
 							$propertyName,
-							$propertyValue,
+							$value,
+							$valueType
 						]
 					);
 				} else {
 					$this->connection->executeUpdate($updateStatement,
 						[
-							$propertyValue,
+							$value,
+							$valueType,
 							$this->user->getUID(),
 							$this->formatPath($path),
 							$propertyName,
@@ -367,8 +381,40 @@ class CustomPropertiesBackend implements BackendInterface {
 	private function formatPath(string $path): string {
 		if (strlen($path) > 250) {
 			return sha1($path);
+		}
+
+		return $path;
+	}
+
+	/**
+	 * @param mixed $value
+	 * @return array
+	 */
+	private function encodeValueForDatabase($value): array {
+		if (is_scalar($value)) {
+			$valueType = self::PROPERTY_TYPE_STRING;
+		} elseif ($value instanceof Complex) {
+			$valueType = self::PROPERTY_TYPE_XML;
+			$value = $value->getXml();
 		} else {
-			return $path;
+			$valueType = self::PROPERTY_TYPE_OBJECT;
+			$value = serialize($value);
+		}
+		return [$value, $valueType];
+	}
+
+	/**
+	 * @return mixed|Complex|string
+	 */
+	private function decodeValueFromDatabase(string $value, int $valueType) {
+		switch ($valueType) {
+			case self::PROPERTY_TYPE_XML:
+				return new Complex($value);
+			case self::PROPERTY_TYPE_OBJECT:
+				return unserialize($value);
+			case self::PROPERTY_TYPE_STRING:
+			default:
+				return $value;
 		}
 	}
 }
diff --git a/apps/dav/lib/Migration/RemoveObjectProperties.php b/apps/dav/lib/Migration/RemoveObjectProperties.php
new file mode 100644
index 00000000000..c72dfbebfea
--- /dev/null
+++ b/apps/dav/lib/Migration/RemoveObjectProperties.php
@@ -0,0 +1,65 @@
+<?php
+/**
+ * @copyright Copyright (c) 2021, Thomas Citharel <nextcloud@tcit.fr>.
+ *
+ * @author Thomas Citharel <nextcloud@tcit.fr>
+ *
+ * @license AGPL-3.0
+ *
+ * This code is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU Affero General Public License, version 3,
+ * as published by the Free Software Foundation.
+ *
+ * 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, version 3,
+ * along with this program. If not, see <http://www.gnu.org/licenses/>
+ *
+ */
+namespace OCA\DAV\Migration;
+
+use OCP\DB\QueryBuilder\IQueryBuilder;
+use OCP\IDBConnection;
+use OCP\Migration\IOutput;
+use OCP\Migration\IRepairStep;
+
+class RemoveObjectProperties implements IRepairStep {
+	private const RESOURCE_TYPE_PROPERTY = '{DAV:}resourcetype';
+	private const ME_CARD_PROPERTY = '{http://calendarserver.org/ns/}me-card';
+	private const CALENDAR_TRANSP_PROPERTY = '{urn:ietf:params:xml:ns:caldav}schedule-calendar-transp';
+
+	/** @var IDBConnection */
+	private $connection;
+
+	/**
+	 * RemoveObjectProperties constructor.
+	 *
+	 * @param IDBConnection $connection
+	 */
+	public function __construct(IDBConnection $connection) {
+		$this->connection = $connection;
+	}
+
+	/**
+	 * @inheritdoc
+	 */
+	public function getName() {
+		return 'Remove invalid object properties';
+	}
+
+	/**
+	 * @inheritdoc
+	 */
+	public function run(IOutput $output) {
+		$query = $this->connection->getQueryBuilder();
+		$updated = $query->delete('properties')
+			->where($query->expr()->in('propertyname', $query->createNamedParameter([self::RESOURCE_TYPE_PROPERTY, self::ME_CARD_PROPERTY, self::CALENDAR_TRANSP_PROPERTY], IQueryBuilder::PARAM_STR_ARRAY)))
+			->andWhere($query->expr()->eq('propertyvalue', $query->createNamedParameter('Object')))
+			->executeStatement();
+
+		$output->info("$updated invalid object properties removed.");
+	}
+}
diff --git a/apps/dav/lib/Migration/Version1024Date20211221144219.php b/apps/dav/lib/Migration/Version1024Date20211221144219.php
new file mode 100644
index 00000000000..b93f8ac801e
--- /dev/null
+++ b/apps/dav/lib/Migration/Version1024Date20211221144219.php
@@ -0,0 +1,58 @@
+<?php
+
+declare(strict_types=1);
+
+namespace OCA\DAV\Migration;
+
+use Closure;
+use Doctrine\DBAL\Schema\SchemaException;
+use OCA\DAV\DAV\CustomPropertiesBackend;
+use OCP\DB\ISchemaWrapper;
+use OCP\DB\Types;
+use OCP\Migration\IOutput;
+use OCP\Migration\SimpleMigrationStep;
+
+/**
+ * Auto-generated migration step: Please modify to your needs!
+ */
+class Version1024Date20211221144219 extends SimpleMigrationStep {
+
+	/**
+	 * @param IOutput $output
+	 * @param Closure $schemaClosure The `\Closure` returns a `ISchemaWrapper`
+	 * @param array $options
+	 */
+	public function preSchemaChange(IOutput $output, Closure $schemaClosure, array $options): void {
+	}
+
+	/**
+	 * @param IOutput $output
+	 * @param Closure $schemaClosure The `\Closure` returns a `ISchemaWrapper`
+	 * @param array $options
+	 * @return null|ISchemaWrapper
+	 * @throws SchemaException
+	 */
+	public function changeSchema(IOutput $output, Closure $schemaClosure, array $options): ?ISchemaWrapper {
+		/** @var ISchemaWrapper $schema */
+		$schema = $schemaClosure();
+		$propertiesTable = $schema->getTable('properties');
+
+		if ($propertiesTable->hasColumn('valuetype')) {
+			return null;
+		}
+		$propertiesTable->addColumn('valuetype', Types::SMALLINT, [
+			'notnull' => false,
+			'default' => CustomPropertiesBackend::PROPERTY_TYPE_STRING
+		]);
+
+		return $schema;
+	}
+
+	/**
+	 * @param IOutput $output
+	 * @param Closure $schemaClosure The `\Closure` returns a `ISchemaWrapper`
+	 * @param array $options
+	 */
+	public function postSchemaChange(IOutput $output, Closure $schemaClosure, array $options): void {
+	}
+}