diff --git a/apps/files_sharing/ajax/shareinfo.php b/apps/files_sharing/ajax/shareinfo.php
index 31b8e00f496ed..b9b29022cc346 100644
--- a/apps/files_sharing/ajax/shareinfo.php
+++ b/apps/files_sharing/ajax/shareinfo.php
@@ -53,11 +53,12 @@
 
 $data = \OCA\Files_Sharing\Helper::setupFromToken($token, $relativePath, $password);
 
-$linkItem = $data['linkItem'];
+/** @var \OCP\Share\IShare $share */
+$share = $data['share'];
 // Load the files
 $path = $data['realPath'];
 
-$isWritable = $linkItem['permissions'] & (\OCP\Constants::PERMISSION_UPDATE | \OCP\Constants::PERMISSION_CREATE);
+$isWritable = $share->getPermissions() & (\OCP\Constants::PERMISSION_UPDATE | \OCP\Constants::PERMISSION_CREATE);
 if (!$isWritable) {
 	\OC\Files\Filesystem::addStorageWrapper('readonly', function ($mountPoint, $storage) {
 		return new \OC\Files\Storage\Wrapper\PermissionsMask(array('storage' => $storage, 'mask' => \OCP\Constants::PERMISSION_READ + \OCP\Constants::PERMISSION_SHARE));
@@ -67,10 +68,6 @@
 $rootInfo = \OC\Files\Filesystem::getFileInfo($path);
 $rootView = new \OC\Files\View('');
 
-$shareManager = \OC::$server->getShareManager();
-$share = $shareManager->getShareByToken($token);
-$sharePermissions= (int)$share->getPermissions();
-
 if($rootInfo === false || !($share->getPermissions() & \OCP\Constants::PERMISSION_READ)) {
 	OCP\JSON::error(array('data' => 'Share is not readable.'));
 	exit();
@@ -98,11 +95,11 @@ function getChildInfo($dir, $view, $sharePermissions) {
 
 $result = \OCA\Files\Helper::formatFileInfo($rootInfo);
 $result['mtime'] = $result['mtime'] / 1000;
-$result['permissions'] = (int)$result['permissions'] & $sharePermissions;
+$result['permissions'] = (int)$result['permissions'] & $share->getPermissions();
 
 
 if ($rootInfo->getType() === 'dir') {
-	$result['children'] = getChildInfo($rootInfo, $rootView, $sharePermissions);
+	$result['children'] = getChildInfo($rootInfo, $rootView, $share->getPermissions());
 }
 
 OCP\JSON::success(array('data' => $result));
diff --git a/apps/files_sharing/lib/Helper.php b/apps/files_sharing/lib/Helper.php
index 2353a281b7e24..67312ae97cdcb 100644
--- a/apps/files_sharing/lib/Helper.php
+++ b/apps/files_sharing/lib/Helper.php
@@ -31,6 +31,7 @@
 use OC\Files\Filesystem;
 use OC\Files\View;
 use OCP\Files\NotFoundException;
+use OCP\Share\Exceptions\ShareNotFound;
 use OCP\User;
 
 class Helper {
@@ -53,29 +54,23 @@ public static function registerHooks() {
 	public static function setupFromToken($token, $relativePath = null, $password = null) {
 		\OC_User::setIncognitoMode(true);
 
-		$linkItem = \OCP\Share::getShareByToken($token, !$password);
-		if($linkItem === false || ($linkItem['item_type'] !== 'file' && $linkItem['item_type'] !== 'folder')) {
+		$shareManager = \OC::$server->getShareManager();
+
+		try {
+			$share = $shareManager->getShareByToken($token);
+		} catch (ShareNotFound $e) {
 			\OC_Response::setStatus(404);
 			\OCP\Util::writeLog('core-preview', 'Passed token parameter is not valid', \OCP\Util::DEBUG);
 			exit;
 		}
 
-		if(!isset($linkItem['uid_owner']) || !isset($linkItem['file_source'])) {
-			\OC_Response::setStatus(500);
-			\OCP\Util::writeLog('core-preview', 'Passed token seems to be valid, but it does not contain all necessary information . ("' . $token . '")', \OCP\Util::WARN);
-			exit;
-		}
+		\OCP\JSON::checkUserExists($share->getShareOwner());
+		\OC_Util::tearDownFS();
+		\OC_Util::setupFS($share->getShareOwner());
 
-		$rootLinkItem = \OCP\Share::resolveReShare($linkItem);
-		$path = null;
-		if (isset($rootLinkItem['uid_owner'])) {
-			\OCP\JSON::checkUserExists($rootLinkItem['uid_owner']);
-			\OC_Util::tearDownFS();
-			\OC_Util::setupFS($rootLinkItem['uid_owner']);
-		}
 
 		try {
-			$path = Filesystem::getPath($linkItem['file_source']);
+			$path = Filesystem::getPath($share->getNodeId());
 		} catch (NotFoundException $e) {
 			\OCP\Util::writeLog('share', 'could not resolve linkItem', \OCP\Util::DEBUG);
 			\OC_Response::setStatus(404);
@@ -83,15 +78,8 @@ public static function setupFromToken($token, $relativePath = null, $password =
 			exit();
 		}
 
-		if (!isset($linkItem['item_type'])) {
-			\OCP\Util::writeLog('share', 'No item type set for share id: ' . $linkItem['id'], \OCP\Util::ERROR);
-			\OC_Response::setStatus(404);
-			\OCP\JSON::error(array('success' => false));
-			exit();
-		}
-
-		if (isset($linkItem['share_with']) && (int)$linkItem['share_type'] === \OCP\Share::SHARE_TYPE_LINK) {
-			if (!self::authenticate($linkItem, $password)) {
+		if ($share->getShareType() === \OCP\Share::SHARE_TYPE_LINK && $share->getPassword() !== null) {
+			if (!self::authenticate($share, $password)) {
 				\OC_Response::setStatus(403);
 				\OCP\JSON::error(array('success' => false));
 				exit();
@@ -105,7 +93,7 @@ public static function setupFromToken($token, $relativePath = null, $password =
 		}
 
 		return array(
-			'linkItem' => $linkItem,
+			'share' => $share,
 			'basePath' => $basePath,
 			'realPath' => $path
 		);
@@ -114,53 +102,29 @@ public static function setupFromToken($token, $relativePath = null, $password =
 	/**
 	 * Authenticate link item with the given password
 	 * or with the session if no password was given.
-	 * @param array $linkItem link item array
+	 * @param \OCP\Share\IShare $share
 	 * @param string $password optional password
 	 *
 	 * @return boolean true if authorized, false otherwise
 	 */
-	public static function authenticate($linkItem, $password = null) {
+	public static function authenticate($share, $password = null) {
+		$shareManager = \OC::$server->getShareManager();
+
 		if ($password !== null) {
-			if ($linkItem['share_type'] == \OCP\Share::SHARE_TYPE_LINK) {
-				// Check Password
-				$newHash = '';
-				if(\OC::$server->getHasher()->verify($password, $linkItem['share_with'], $newHash)) {
-					// Save item id in session for future requests
-					\OC::$server->getSession()->set('public_link_authenticated', (string) $linkItem['id']);
-
-					/**
-					 * FIXME: Migrate old hashes to new hash format
-					 * Due to the fact that there is no reasonable functionality to update the password
-					 * of an existing share no migration is yet performed there.
-					 * The only possibility is to update the existing share which will result in a new
-					 * share ID and is a major hack.
-					 *
-					 * In the future the migration should be performed once there is a proper method
-					 * to update the share's password. (for example `$share->updatePassword($password)`
-					 *
-					 * @link https://github.com/owncloud/core/issues/10671
-					 */
-					if(!empty($newHash)) {
-
-					}
-				} else {
-					return false;
+			if ($share->getShareType() === \OCP\Share::SHARE_TYPE_LINK) {
+				if ($shareManager->checkPassword($share, $password)) {
+					\OC::$server->getSession()->set('public_link_authenticated', (string)$share->getId());
+					return true;
 				}
-			} else {
-				\OCP\Util::writeLog('share', 'Unknown share type '.$linkItem['share_type']
-					.' for share id '.$linkItem['id'], \OCP\Util::ERROR);
-				return false;
 			}
-
-		}
-		else {
+		} else {
 			// not authenticated ?
-			if ( ! \OC::$server->getSession()->exists('public_link_authenticated')
-				|| \OC::$server->getSession()->get('public_link_authenticated') !== (string)$linkItem['id']) {
-				return false;
+			if (\OC::$server->getSession()->exists('public_link_authenticated')
+				&& \OC::$server->getSession()->get('public_link_authenticated') !== (string)$share->getId()) {
+				return true;
 			}
 		}
-		return true;
+		return false;
 	}
 
 	public static function getSharesFromItem($target) {