Explicitly add the current principal to the acl in case of group sharing

14 files changed, 138 insertions, 66 deletions

diff --git a/apps/dav/appinfo/application.php b/apps/dav/appinfo/application.php
index d06daf97f54..6e86f422d42 100644
--- a/apps/dav/appinfo/application.php
+++ b/apps/dav/appinfo/application.php
@@ -27,6 +27,7 @@ use OCA\DAV\CardDAV\CardDavBackend;
 use OCA\DAV\CardDAV\ContactsManager;
 use OCA\DAV\CardDAV\SyncJob;
 use OCA\DAV\CardDAV\SyncService;
+use OCA\DAV\DAV\GroupPrincipalBackend;
 use OCA\DAV\HookManager;
 use OCA\Dav\Migration\AddressBookAdapter;
 use OCA\Dav\Migration\CalendarAdapter;
@@ -83,7 +84,8 @@ class Application extends App {
 				$c->getServer()->getUserManager(),
 				$c->getServer()->getGroupManager()
 			);
-			return new CardDavBackend($db, $principal, $dispatcher);
+			$groupPrincipal = new GroupPrincipalBackend($c->getServer()->getGroupManager());
+			return new CardDavBackend($db, $principal, $groupPrincipal, $dispatcher);
 		});
 
 		$container->registerService('CalDavBackend', function($c) {
@@ -93,7 +95,8 @@ class Application extends App {
 				$c->getServer()->getUserManager(),
 				$c->getServer()->getGroupManager()
 			);
-			return new CalDavBackend($db, $principal);
+			$groupPrincipal = new GroupPrincipalBackend($c->getServer()->getGroupManager());
+			return new CalDavBackend($db, $principal, $groupPrincipal);
 		});
 
 		$container->registerService('MigrateAddressbooks', function($c) {
@@ -217,7 +220,7 @@ class Application extends App {
 			$migration = $this->getContainer()->query('BirthdayService');
 			$userManager = $this->getContainer()->getServer()->getUserManager();
 
-			$userManager->callForAllUsers(function($user) use($migration) {
+			$userManager->callForAllUsers(function ($user) use ($migration) {
 				/** @var IUser $user */
 				$migration->syncUser($user->getUID());
 			});
@@ -225,4 +228,11 @@ class Application extends App {
 			$this->getContainer()->getServer()->getLogger()->logException($ex);
 		}
 	}
+
+	/**
+	 * @return CardDavBackend
+	 */
+	public function getCardDavBackend() {
+		return $this->getContainer()->query('CardDavBackend');
+	}
 }
diff --git a/apps/dav/appinfo/register_command.php b/apps/dav/appinfo/register_command.php
index 570848f0b23..45b43d6f2d5 100644
--- a/apps/dav/appinfo/register_command.php
+++ b/apps/dav/appinfo/register_command.php
@@ -34,7 +34,7 @@ $app = new Application();
 
 /** @var Symfony\Component\Console\Application $application */
 $application->add(new CreateCalendar($userManager, $groupManager, $dbConnection));
-$application->add(new CreateAddressBook($userManager, $app->getContainer()->query('CardDavBackend')));
+$application->add(new CreateAddressBook($userManager, $app->getCardDavBackend()));
 $application->add(new SyncSystemAddressBook($app->getSyncService()));
 $application->add(new SyncBirthdayCalendar($userManager, $app->getContainer()->query('BirthdayService')));
 $application->add(new MigrateAddressbooks($userManager, $app->getContainer()->query('MigrateAddressbooks')));
diff --git a/apps/dav/appinfo/v1/caldav.php b/apps/dav/appinfo/v1/caldav.php
index f2c886e0fdd..3e1a7ce6253 100644
--- a/apps/dav/appinfo/v1/caldav.php
+++ b/apps/dav/appinfo/v1/caldav.php
@@ -23,11 +23,12 @@
 
 // Backends
 use OCA\DAV\CalDAV\CalDavBackend;
+use OCA\DAV\CalDAV\CalendarRoot;
 use OCA\DAV\Connector\Sabre\Auth;
 use OCA\DAV\Connector\Sabre\ExceptionLoggerPlugin;
 use OCA\DAV\Connector\Sabre\MaintenancePlugin;
 use OCA\DAV\Connector\Sabre\Principal;
-use Sabre\CalDAV\CalendarRoot;
+use OCA\DAV\DAV\GroupPrincipalBackend;
 
 $authBackend = new Auth(
 	\OC::$server->getSession(),
@@ -41,7 +42,8 @@ $principalBackend = new Principal(
 	'principals/'
 );
 $db = \OC::$server->getDatabaseConnection();
-$calDavBackend = new CalDavBackend($db, $principalBackend);
+$groupPrincipal = new GroupPrincipalBackend(\OC::$server->getGroupManager());
+$calDavBackend = new CalDavBackend($db, $principalBackend, $groupPrincipal);
 
 // Root nodes
 $principalCollection = new \Sabre\CalDAV\Principal\Collection($principalBackend);
diff --git a/apps/dav/appinfo/v1/carddav.php b/apps/dav/appinfo/v1/carddav.php
index 44abcbaa190..ac6ffea2506 100644
--- a/apps/dav/appinfo/v1/carddav.php
+++ b/apps/dav/appinfo/v1/carddav.php
@@ -42,14 +42,14 @@ $principalBackend = new Principal(
 	'principals/'
 );
 $db = \OC::$server->getDatabaseConnection();
-$cardDavBackend = new CardDavBackend($db, $principalBackend);
+$app = new \OCA\Dav\AppInfo\Application();
 
 // Root nodes
 $principalCollection = new \Sabre\CalDAV\Principal\Collection($principalBackend);
 $principalCollection->disableListing = true; // Disable listing
 
-$addressBookRoot = new AddressBookRoot($principalBackend, $cardDavBackend);
-$addressBookRoot->disableListing = true; // Disable listing
+$addressBookRoot = new AddressBookRoot($principalBackend, $app->getCardDavBackend());
+$addressBookRoot->disableListing = false; // Disable listing
 
 $nodes = array(
 	$principalCollection,
diff --git a/apps/dav/command/createcalendar.php b/apps/dav/command/createcalendar.php
index d7f82dd0e52..a1a15513a00 100644
--- a/apps/dav/command/createcalendar.php
+++ b/apps/dav/command/createcalendar.php
@@ -22,6 +22,7 @@ namespace OCA\DAV\Command;
 
 use OCA\DAV\CalDAV\CalDavBackend;
 use OCA\DAV\Connector\Sabre\Principal;
+use OCA\DAV\DAV\GroupPrincipalBackend;
 use OCP\IDBConnection;
 use OCP\IGroupManager;
 use OCP\IUserManager;
@@ -73,9 +74,10 @@ class CreateCalendar extends Command {
 			$this->userManager,
 			$this->groupManager
 		);
+		$groupPrincipal = new GroupPrincipalBackend($this->groupManager);
 
 		$name = $input->getArgument('name');
-		$caldav = new CalDavBackend($this->dbConnection, $principalBackend);
+		$caldav = new CalDavBackend($this->dbConnection, $principalBackend, $groupPrincipal);
 		$caldav->createCalendar("principals/users/$user", $name, []);
 	}
 }
diff --git a/apps/dav/lib/caldav/caldavbackend.php b/apps/dav/lib/caldav/caldavbackend.php
index bb50100d9a2..a188d652eed 100644
--- a/apps/dav/lib/caldav/caldavbackend.php
+++ b/apps/dav/lib/caldav/caldavbackend.php
@@ -22,6 +22,7 @@
 
 namespace OCA\DAV\CalDAV;
 
+use OCA\DAV\DAV\GroupPrincipalBackend;
 use OCA\DAV\DAV\Sharing\IShareable;
 use OCP\DB\QueryBuilder\IQueryBuilder;
 use OCA\DAV\Connector\Sabre\Principal;
@@ -35,7 +36,9 @@ use Sabre\CalDAV\Plugin;
 use Sabre\CalDAV\Xml\Property\ScheduleCalendarTransp;
 use Sabre\CalDAV\Xml\Property\SupportedCalendarComponentSet;
 use Sabre\DAV;
+use Sabre\DAV\Exception\BadRequest;
 use Sabre\DAV\Exception\Forbidden;
+use Sabre\DAV\PropPatch;
 use Sabre\HTTP\URLUtil;
 use Sabre\VObject\DateTimeParser;
 use Sabre\VObject\Reader;
@@ -104,12 +107,13 @@ class CalDavBackend extends AbstractBackend implements SyncSupport, Subscription
 	 * CalDavBackend constructor.
 	 *
 	 * @param IDBConnection $db
-	 * @param Principal $principalBackend
+	 * @param $userPrincipalBackend
+	 * @param GroupPrincipalBackend $groupPrincipalBackend
 	 */
-	public function __construct(IDBConnection $db, Principal $principalBackend) {
+	public function __construct(IDBConnection $db, $userPrincipalBackend, GroupPrincipalBackend $groupPrincipalBackend) {
 		$this->db = $db;
-		$this->principalBackend = $principalBackend;
-		$this->sharingBackend = new Backend($this->db, $principalBackend, 'calendar');
+		$this->principalBackend = $userPrincipalBackend;
+		$this->sharingBackend = new Backend($this->db, $userPrincipalBackend, $groupPrincipalBackend, 'calendar');
 	}
 
 	/**
@@ -340,6 +344,7 @@ class CalDavBackend extends AbstractBackend implements SyncSupport, Subscription
 	 * @param string $calendarUri
 	 * @param array $properties
 	 * @return int
+	 * @throws DAV\Exception
 	 */
 	function createCalendar($principalUri, $calendarUri, array $properties) {
 		$values = [
@@ -391,10 +396,10 @@ class CalDavBackend extends AbstractBackend implements SyncSupport, Subscription
 	 *
 	 * Read the PropPatch documentation for more info and examples.
 	 *
-	 * @param \Sabre\DAV\PropPatch $propPatch
-	 * @return void
+	 * @param int $calendarId
+	 * @param PropPatch $propPatch
 	 */
-	function updateCalendar($calendarId, \Sabre\DAV\PropPatch $propPatch) {
+	function updateCalendar($calendarId, PropPatch $propPatch) {
 		$supportedProperties = array_keys($this->propertyMap);
 		$supportedProperties[] = '{' . Plugin::NS_CALDAV . '}schedule-calendar-transp';
 
@@ -1034,6 +1039,7 @@ class CalDavBackend extends AbstractBackend implements SyncSupport, Subscription
 	 * @param string $uri
 	 * @param array $properties
 	 * @return mixed
+	 * @throws Forbidden
 	 */
 	function createSubscription($principalUri, $uri, array $properties) {
 
@@ -1082,10 +1088,10 @@ class CalDavBackend extends AbstractBackend implements SyncSupport, Subscription
 	 * Read the PropPatch documentation for more info and examples.
 	 *
 	 * @param mixed $subscriptionId
-	 * @param \Sabre\DAV\PropPatch $propPatch
+	 * @param PropPatch $propPatch
 	 * @return void
 	 */
-	function updateSubscription($subscriptionId, DAV\PropPatch $propPatch) {
+	function updateSubscription($subscriptionId, PropPatch $propPatch) {
 		$supportedProperties = array_keys($this->subscriptionPropertyMap);
 		$supportedProperties[] = '{http://calendarserver.org/ns/}source';
 
@@ -1275,6 +1281,7 @@ class CalDavBackend extends AbstractBackend implements SyncSupport, Subscription
 	 *
 	 * @param string $calendarData
 	 * @return array
+	 * @throws BadRequest
 	 */
 	protected function getDenormalizedData($calendarData) {
 
@@ -1292,7 +1299,7 @@ class CalDavBackend extends AbstractBackend implements SyncSupport, Subscription
 			}
 		}
 		if (!$componentType) {
-			throw new \Sabre\DAV\Exception\BadRequest('Calendar objects must have a VJOURNAL, VEVENT or VTODO component');
+			throw new BadRequest('Calendar objects must have a VJOURNAL, VEVENT or VTODO component');
 		}
 		if ($componentType === 'VEVENT' && $component->DTSTART) {
 			$firstOccurence = $component->DTSTART->getDateTime()->getTimeStamp();
@@ -1359,19 +1366,21 @@ class CalDavBackend extends AbstractBackend implements SyncSupport, Subscription
 
 	/**
 	 * @param int $resourceId
+	 * @param string $currentPrincipal
 	 * @return array
 	 */
-	public function getShares($resourceId) {
-		return $this->sharingBackend->getShares($resourceId);
+	public function getShares($resourceId, $currentPrincipal) {
+		return $this->sharingBackend->getShares($resourceId, $currentPrincipal);
 	}
 
 	/**
 	 * @param int $resourceId
 	 * @param array $acl
+	 * @param string $currentPrincipal
 	 * @return array
 	 */
-	public function applyShareAcl($resourceId, $acl) {
-		return $this->sharingBackend->applyShareAcl($resourceId, $acl);
+	public function applyShareAcl($resourceId, $acl, $currentPrincipal) {
+		return $this->sharingBackend->applyShareAcl($resourceId, $acl, $currentPrincipal);
 	}
 
 	private function convertPrincipal($principalUri, $toV2) {
diff --git a/apps/dav/lib/caldav/calendar.php b/apps/dav/lib/caldav/calendar.php
index 1e87f9b4333..bc2646eb60d 100644
--- a/apps/dav/lib/caldav/calendar.php
+++ b/apps/dav/lib/caldav/calendar.php
@@ -75,7 +75,7 @@ class Calendar extends \Sabre\CalDAV\Calendar implements IShareable {
 	function getShares() {
 		/** @var CalDavBackend $calDavBackend */
 		$calDavBackend = $this->caldavBackend;
-		return $calDavBackend->getShares($this->getResourceId());
+		return $calDavBackend->getShares($this->getResourceId(), parent::getOwner());
 	}
 
 	/**
@@ -90,7 +90,7 @@ class Calendar extends \Sabre\CalDAV\Calendar implements IShareable {
 
 		/** @var CalDavBackend $calDavBackend */
 		$calDavBackend = $this->caldavBackend;
-		return $calDavBackend->applyShareAcl($this->getResourceId(), $acl);
+		return $calDavBackend->applyShareAcl($this->getResourceId(), $acl, parent::getOwner());
 	}
 
 	function getChildACL() {
diff --git a/apps/dav/lib/carddav/addressbook.php b/apps/dav/lib/carddav/addressbook.php
index bb9d13b981e..70456afbd0f 100644
--- a/apps/dav/lib/carddav/addressbook.php
+++ b/apps/dav/lib/carddav/addressbook.php
@@ -66,7 +66,7 @@ class AddressBook extends \Sabre\CardDAV\AddressBook implements IShareable {
 	function getShares() {
 		/** @var CardDavBackend $carddavBackend */
 		$carddavBackend = $this->carddavBackend;
-		return $carddavBackend->getShares($this->getResourceId());
+		return $carddavBackend->getShares($this->getResourceId(), $this->getOwner());
 	}
 
 	function getACL() {
@@ -113,7 +113,7 @@ class AddressBook extends \Sabre\CardDAV\AddressBook implements IShareable {
 
 		/** @var CardDavBackend $carddavBackend */
 		$carddavBackend = $this->carddavBackend;
-		return $carddavBackend->applyShareAcl($this->getResourceId(), $acl);
+		return $carddavBackend->applyShareAcl($this->getResourceId(), $acl, parent::getOwner());
 	}
 
 	function getChild($name) {
diff --git a/apps/dav/lib/carddav/carddavbackend.php b/apps/dav/lib/carddav/carddavbackend.php
index bfb6ea82ad7..89154c39d37 100644
--- a/apps/dav/lib/carddav/carddavbackend.php
+++ b/apps/dav/lib/carddav/carddavbackend.php
@@ -25,6 +25,7 @@
 namespace OCA\DAV\CardDAV;
 
 use OCA\DAV\Connector\Sabre\Principal;
+use OCA\DAV\DAV\GroupPrincipalBackend;
 use OCP\DB\QueryBuilder\IQueryBuilder;
 use OCA\DAV\DAV\Sharing\Backend;
 use OCA\DAV\DAV\Sharing\IShareable;
@@ -34,6 +35,7 @@ use Sabre\CardDAV\Backend\BackendInterface;
 use Sabre\CardDAV\Backend\SyncSupport;
 use Sabre\CardDAV\Plugin;
 use Sabre\DAV\Exception\BadRequest;
+use Sabre\DAV\PropPatch;
 use Sabre\HTTP\URLUtil;
 use Sabre\VObject\Component\VCard;
 use Sabre\VObject\Reader;
@@ -73,16 +75,18 @@ class CardDavBackend implements BackendInterface, SyncSupport {
 	 * CardDavBackend constructor.
 	 *
 	 * @param IDBConnection $db
-	 * @param Principal $principalBackend
+	 * @param Principal $userPrincipalBackend
+	 * @param GroupPrincipalBackend $groupPrincipalBackend
 	 * @param EventDispatcherInterface $dispatcher
 	 */
 	public function __construct(IDBConnection $db,
-								Principal $principalBackend,
+								Principal $userPrincipalBackend,
+								GroupPrincipalBackend $groupPrincipalBackend,
 								EventDispatcherInterface $dispatcher = null) {
 		$this->db = $db;
-		$this->principalBackend = $principalBackend;
+		$this->principalBackend = $userPrincipalBackend;
 		$this->dispatcher = $dispatcher;
-		$this->sharingBackend = new Backend($this->db, $principalBackend, 'addressbook');
+		$this->sharingBackend = new Backend($this->db, $userPrincipalBackend, $groupPrincipalBackend, 'addressbook');
 	}
 
 	/**
@@ -164,6 +168,7 @@ class CardDavBackend implements BackendInterface, SyncSupport {
 
 	/**
 	 * @param int $addressBookId
+	 * @return array|null
 	 */
 	public function getAddressBookById($addressBookId) {
 		$query = $this->db->getQueryBuilder();
@@ -190,7 +195,8 @@ class CardDavBackend implements BackendInterface, SyncSupport {
 	}
 
 	/**
-	 * @param $addressBookUri
+	 * @param string $principal
+	 * @param string $addressBookUri
 	 * @return array|null
 	 */
 	public function getAddressBooksByUri($principal, $addressBookUri) {
@@ -232,10 +238,10 @@ class CardDavBackend implements BackendInterface, SyncSupport {
 	 * Read the PropPatch documentation for more info and examples.
 	 *
 	 * @param string $addressBookId
-	 * @param \Sabre\DAV\PropPatch $propPatch
+	 * @param PropPatch $propPatch
 	 * @return void
 	 */
-	function updateAddressBook($addressBookId, \Sabre\DAV\PropPatch $propPatch) {
+	function updateAddressBook($addressBookId, PropPatch $propPatch) {
 		$supportedProperties = [
 			'{DAV:}displayname',
 			'{' . Plugin::NS_CARDDAV . '}addressbook-description',
@@ -870,10 +876,12 @@ class CardDavBackend implements BackendInterface, SyncSupport {
 	 *   * readOnly - boolean
 	 *   * summary - Optional, a description for the share
 	 *
+	 * @param $addressBookId
+	 * @param string $currentPrincipal
 	 * @return array
 	 */
-	public function getShares($addressBookId) {
-		return $this->sharingBackend->getShares($addressBookId);
+	public function getShares($addressBookId, $currentPrincipal) {
+		return $this->sharingBackend->getShares($addressBookId, $currentPrincipal);
 	}
 
 	/**
@@ -971,10 +979,11 @@ class CardDavBackend implements BackendInterface, SyncSupport {
 	 * For shared address books the sharee is set in the ACL of the address book
 	 * @param $addressBookId
 	 * @param $acl
+	 * @param string $currentPrincipal
 	 * @return array
 	 */
-	public function applyShareAcl($addressBookId, $acl) {
-		return $this->sharingBackend->applyShareAcl($addressBookId, $acl);
+	public function applyShareAcl($addressBookId, $acl, $currentPrincipal) {
+		return $this->sharingBackend->applyShareAcl($addressBookId, $acl, $currentPrincipal);
 	}
 
 	private function convertPrincipal($principalUri, $toV2) {
diff --git a/apps/dav/lib/dav/sharing/backend.php b/apps/dav/lib/dav/sharing/backend.php
index ffc4193e34b..9ef1a07ebc6 100644
--- a/apps/dav/lib/dav/sharing/backend.php
+++ b/apps/dav/lib/dav/sharing/backend.php
@@ -23,6 +23,7 @@
 namespace OCA\DAV\DAV\Sharing;
 
 use OCA\DAV\Connector\Sabre\Principal;
+use OCA\DAV\DAV\GroupPrincipalBackend;
 use OCP\IDBConnection;
 
 class Backend {
@@ -30,7 +31,9 @@ class Backend {
 	/** @var IDBConnection */
 	private $db;
 	/** @var Principal */
-	private $principalBackend;
+	private $userPrincipalBackend;
+	/** @var GroupPrincipalBackend */
+	private $groupPrincipalBackend;
 	/** @var string */
 	private $resourceType;
 
@@ -40,12 +43,14 @@ class Backend {
 
 	/**
 	 * @param IDBConnection $db
-	 * @param Principal $principalBackend
+	 * @param Principal $userPrincipalBackend
+	 * @param GroupPrincipalBackend $groupPrincipalBackend
 	 * @param string $resourceType
 	 */
-	public function __construct(IDBConnection $db, Principal $principalBackend, $resourceType) {
+	public function __construct(IDBConnection $db, Principal $userPrincipalBackend, GroupPrincipalBackend $groupPrincipalBackend, $resourceType) {
 		$this->db = $db;
-		$this->principalBackend = $principalBackend;
+		$this->userPrincipalBackend = $userPrincipalBackend;
+		$this->groupPrincipalBackend = $groupPrincipalBackend;
 		$this->resourceType = $resourceType;
 	}
 
@@ -143,9 +148,10 @@ class Backend {
 	 *   * summary - Optional, a description for the share
 	 *
 	 * @param int $resourceId
+	 * @param string $currentPrincipal
 	 * @return array
 	 */
-	public function getShares($resourceId) {
+	public function getShares($resourceId, $currentPrincipal) {
 		$query = $this->db->getQueryBuilder();
 		$result = $query->select(['principaluri', 'access'])
 			->from('dav_shares')
@@ -155,13 +161,31 @@ class Backend {
 
 		$shares = [];
 		while($row = $result->fetch()) {
-			$p = $this->principalBackend->getPrincipalByPath($row['principaluri']);
+			$p = $this->userPrincipalBackend->getPrincipalByPath($row['principaluri']);
+			if (is_null($p)) {
+				$p = $this->groupPrincipalBackend->getPrincipalByPath($row['principaluri']);
+				if (is_null($p)) {
+					continue;
+				}
+				// also add the current user if it is member of the group
+				$groups = $this->userPrincipalBackend->getGroupMembership($currentPrincipal);
+				if (in_array($row['principaluri'], $groups)) {
+					$ownerPrincipal = $this->userPrincipalBackend->getPrincipalByPath($currentPrincipal);
+					$shares[]= [
+						'href' => "principal:$currentPrincipal",
+						'commonName' => isset($ownerPrincipal['{DAV:}displayname']) ? $ownerPrincipal['{DAV:}displayname'] : '',
+						'status' => 1,
+						'readOnly' => ($row['access'] == self::ACCESS_READ),
+						'{http://owncloud.org/ns}principal' => $currentPrincipal
+					];
+				}
+			}
 			$shares[]= [
 				'href' => "principal:${row['principaluri']}",
 				'commonName' => isset($p['{DAV:}displayname']) ? $p['{DAV:}displayname'] : '',
 				'status' => 1,
 				'readOnly' => ($row['access'] == self::ACCESS_READ),
-				'{'.\OCA\DAV\DAV\Sharing\Plugin::NS_OWNCLOUD.'}principal' => $row['principaluri']
+				'{http://owncloud.org/ns}principal' => $row['principaluri']
 			];
 		}
 
@@ -173,11 +197,12 @@ class Backend {
 	 *
 	 * @param int $resourceId
 	 * @param array $acl
+	 * @param string $currentPrincipal
 	 * @return array
 	 */
-	public function applyShareAcl($resourceId, $acl) {
+	public function applyShareAcl($resourceId, $acl, $currentPrincipal) {
 
-		$shares = $this->getShares($resourceId);
+		$shares = $this->getShares($resourceId, $currentPrincipal);
 		foreach ($shares as $share) {
 			$acl[] = [
 				'privilege' => '{DAV:}read',
diff --git a/apps/dav/lib/dav/sharing/ishareable.php b/apps/dav/lib/dav/sharing/ishareable.php
index f6b6bfa8862..b0f3307335b 100644
--- a/apps/dav/lib/dav/sharing/ishareable.php
+++ b/apps/dav/lib/dav/sharing/ishareable.php
@@ -71,4 +71,4 @@ interface IShareable extends INode {
 	 */
 	public function getOwner();
 
-}
\ No newline at end of file
+}
diff --git a/apps/dav/lib/rootcollection.php b/apps/dav/lib/rootcollection.php
index ea796c09175..fd1a1558efd 100644
--- a/apps/dav/lib/rootcollection.php
+++ b/apps/dav/lib/rootcollection.php
@@ -57,7 +57,7 @@ class RootCollection extends SimpleCollection {
 		$systemPrincipals->disableListing = $disableListing;
 		$filesCollection = new Files\RootCollection($userPrincipalBackend, 'principals/users');
 		$filesCollection->disableListing = $disableListing;
-		$caldavBackend = new CalDavBackend($db, $userPrincipalBackend);
+		$caldavBackend = new CalDavBackend($db, $userPrincipalBackend, $groupPrincipalBackend);
 		$calendarRoot = new CalendarRoot($userPrincipalBackend, $caldavBackend, 'principals/users');
 		$calendarRoot->disableListing = $disableListing;
 
@@ -80,12 +80,13 @@ class RootCollection extends SimpleCollection {
 			\OC::$server->getRootFolder(),
 			\OC::$server->getLogger()
 		);
+		$groupPrincipal = new GroupPrincipalBackend(\OC::$server->getGroupManager());
 
-		$usersCardDavBackend = new CardDavBackend($db, $userPrincipalBackend, $dispatcher);
+		$usersCardDavBackend = new CardDavBackend($db, $userPrincipalBackend, $groupPrincipal, $dispatcher);
 		$usersAddressBookRoot = new AddressBookRoot($userPrincipalBackend, $usersCardDavBackend, 'principals/users');
 		$usersAddressBookRoot->disableListing = $disableListing;
 
-		$systemCardDavBackend = new CardDavBackend($db, $userPrincipalBackend, $dispatcher);
+		$systemCardDavBackend = new CardDavBackend($db, $userPrincipalBackend, $groupPrincipal, $dispatcher);
 		$systemAddressBookRoot = new AddressBookRoot(new SystemPrincipalBackend(), $systemCardDavBackend, 'principals/system');
 		$systemAddressBookRoot->disableListing = $disableListing;
 
diff --git a/apps/dav/tests/unit/caldav/caldavbackendtest.php b/apps/dav/tests/unit/caldav/caldavbackendtest.php
index 87a700a473d..db896612276 100644
--- a/apps/dav/tests/unit/caldav/caldavbackendtest.php
+++ b/apps/dav/tests/unit/caldav/caldavbackendtest.php
@@ -25,6 +25,7 @@ use DateTimeZone;
 use OCA\DAV\CalDAV\CalDavBackend;
 use OCA\DAV\CalDAV\Calendar;
 use OCA\DAV\Connector\Sabre\Principal;
+use OCA\DAV\DAV\GroupPrincipalBackend;
 use Sabre\CalDAV\Xml\Property\SupportedCalendarComponentSet;
 use Sabre\DAV\PropPatch;
 use Sabre\DAV\Xml\Property\Href;
@@ -46,6 +47,9 @@ class CalDavBackendTest extends TestCase {
 	/** @var Principal | \PHPUnit_Framework_MockObject_MockObject */
 	private $principal;
 
+	/** @var GroupPrincipalBackend | \PHPUnit_Framework_MockObject_MockObject */
+	private $groupPrincipal;
+
 	const UNIT_TEST_USER = 'principals/users/caldav-unit-test';
 	const UNIT_TEST_USER1 = 'principals/users/caldav-unit-test1';
 	const UNIT_TEST_GROUP = 'principals/groups/caldav-unit-test-group';
@@ -64,9 +68,13 @@ class CalDavBackendTest extends TestCase {
 		$this->principal->expects($this->any())->method('getGroupMembership')
 			->withAnyParameters()
 			->willReturn([self::UNIT_TEST_GROUP]);
+		$this->groupPrincipal = $this->getMockBuilder('OCA\DAV\DAV\GroupPrincipalBackend')
+			->disableOriginalConstructor()
+			->setMethods(['getPrincipalByPath', 'getGroupMembership'])
+			->getMock();
 
 		$db = \OC::$server->getDatabaseConnection();
-		$this->backend = new CalDavBackend($db, $this->principal);
+		$this->backend = new CalDavBackend($db, $this->principal, $this->groupPrincipal);
 
 		$this->tearDown();
 	}
diff --git a/apps/dav/tests/unit/carddav/carddavbackendtest.php b/apps/dav/tests/unit/carddav/carddavbackendtest.php
index 1ee09260c88..38b8a81b2bc 100644
--- a/apps/dav/tests/unit/carddav/carddavbackendtest.php
+++ b/apps/dav/tests/unit/carddav/carddavbackendtest.php
@@ -27,6 +27,7 @@ use InvalidArgumentException;
 use OCA\DAV\CardDAV\AddressBook;
 use OCA\DAV\CardDAV\CardDavBackend;
 use OCA\DAV\Connector\Sabre\Principal;
+use OCA\DAV\DAV\GroupPrincipalBackend;
 use OCP\DB\QueryBuilder\IQueryBuilder;
 use OCP\IDBConnection;
 use Sabre\DAV\PropPatch;
@@ -58,6 +59,9 @@ class CardDavBackendTest extends TestCase {
 	/** @var string */
 	private $dbCardsPropertiesTable = 'cards_properties';
 
+	/** @var GroupPrincipalBackend */
+	private $groupPrincipal;
+
 	const UNIT_TEST_USER = 'principals/users/carddav-unit-test';
 	const UNIT_TEST_USER1 = 'principals/users/carddav-unit-test1';
 	const UNIT_TEST_GROUP = 'principals/groups/carddav-unit-test-group';
@@ -69,17 +73,21 @@ class CardDavBackendTest extends TestCase {
 			->disableOriginalConstructor()
 			->setMethods(['getPrincipalByPath', 'getGroupMembership'])
 			->getMock();
-		$this->principal->method('getPrincipalByPath')
+		$this->principal->expects($this->any())->method('getPrincipalByPath')
 			->willReturn([
 				'uri' => 'principals/best-friend'
 			]);
-		$this->principal->method('getGroupMembership')
+		$this->principal->expects($this->any())->method('getGroupMembership')
 			->withAnyParameters()
 			->willReturn([self::UNIT_TEST_GROUP]);
+		$this->groupPrincipal = $this->getMockBuilder('OCA\DAV\DAV\GroupPrincipalBackend')
+			->disableOriginalConstructor()
+			->setMethods(['getPrincipalByPath', 'getGroupMembership'])
+			->getMock();
 
 		$this->db = \OC::$server->getDatabaseConnection();
 
-		$this->backend = new CardDavBackend($this->db, $this->principal, null);
+		$this->backend = new CardDavBackend($this->db, $this->principal, $this->groupPrincipal, null);
 
 		// start every test with a empty cards_properties and cards table
 		$query = $this->db->getQueryBuilder();
@@ -157,7 +165,7 @@ class CardDavBackendTest extends TestCase {
 
 		/** @var CardDavBackend | \PHPUnit_Framework_MockObject_MockObject $backend */
 		$backend = $this->getMockBuilder('OCA\DAV\CardDAV\CardDavBackend')
-				->setConstructorArgs([$this->db, $this->principal, null])
+				->setConstructorArgs([$this->db, $this->principal, $this->groupPrincipal, null])
 				->setMethods(['updateProperties', 'purgeProperties'])->getMock();
 
 		// create a new address book
@@ -203,7 +211,7 @@ class CardDavBackendTest extends TestCase {
 	public function testMultiCard() {
 
 		$this->backend = $this->getMockBuilder('OCA\DAV\CardDAV\CardDavBackend')
-			->setConstructorArgs([$this->db, $this->principal, null])
+			->setConstructorArgs([$this->db, $this->principal, $this->groupPrincipal, null])
 			->setMethods(['updateProperties'])->getMock();
 
 		// create a new address book
@@ -248,9 +256,8 @@ class CardDavBackendTest extends TestCase {
 	}
 
 	public function testDeleteWithoutCard() {
-
 		$this->backend = $this->getMockBuilder('OCA\DAV\CardDAV\CardDavBackend')
-			->setConstructorArgs([$this->db, $this->principal, null])
+			->setConstructorArgs([$this->db, $this->principal, $this->groupPrincipal, null])
 			->setMethods([
 				'getCardId',
 				'addChange',
@@ -289,9 +296,8 @@ class CardDavBackendTest extends TestCase {
 	}
 
 	public function testSyncSupport() {
-
 		$this->backend = $this->getMockBuilder('OCA\DAV\CardDAV\CardDavBackend')
-			->setConstructorArgs([$this->db, $this->principal, null])
+			->setConstructorArgs([$this->db, $this->principal, $this->groupPrincipal, null])
 			->setMethods(['updateProperties'])->getMock();
 
 		// create a new address book
@@ -321,13 +327,13 @@ class CardDavBackendTest extends TestCase {
 		$exampleBook = new AddressBook($this->backend, $books[0]);
 		$this->backend->updateShares($exampleBook, [['href' => 'principal:principals/best-friend']], []);
 
-		$shares = $this->backend->getShares($exampleBook->getResourceId());
+		$shares = $this->backend->getShares($exampleBook->getResourceId(), null);
 		$this->assertEquals(1, count($shares));
 
 		// adding the same sharee again has no effect
 		$this->backend->updateShares($exampleBook, [['href' => 'principal:principals/best-friend']], []);
 
-		$shares = $this->backend->getShares($exampleBook->getResourceId());
+		$shares = $this->backend->getShares($exampleBook->getResourceId(), null);
 		$this->assertEquals(1, count($shares));
 
 		$books = $this->backend->getAddressBooksForUser('principals/best-friend');
@@ -335,7 +341,7 @@ class CardDavBackendTest extends TestCase {
 
 		$this->backend->updateShares($exampleBook, [], ['principal:principals/best-friend']);
 
-		$shares = $this->backend->getShares($exampleBook->getResourceId());
+		$shares = $this->backend->getShares($exampleBook->getResourceId(), null);
 		$this->assertEquals(0, count($shares));
 
 		$books = $this->backend->getAddressBooksForUser('principals/best-friend');
@@ -349,7 +355,7 @@ class CardDavBackendTest extends TestCase {
 		$cardId = 2;
 
 		$backend = $this->getMockBuilder('OCA\DAV\CardDAV\CardDavBackend')
-			->setConstructorArgs([$this->db, $this->principal, null])
+			->setConstructorArgs([$this->db, $this->principal, $this->groupPrincipal, null])
 			->setMethods(['getCardId'])->getMock();
 
 		$backend->expects($this->any())->method('getCardId')->willReturn($cardId);