Fix share key finding algorithm in various cases

Instead of inaccurate pattern matching, use the list of users who we
know have access to the file to build the list of share keys.

This covers the following cases:

- Move/copy files into a subfolder within a share
- Unsharing from a user
- Deleting files directlry / moving share keys to trashbin

1 files changed, 32 insertions, 22 deletions

diff --git a/apps/files_encryption/lib/keymanager.php b/apps/files_encryption/lib/keymanager.php
index 931469f4b74..9560126ef33 100755
--- a/apps/files_encryption/lib/keymanager.php
+++ b/apps/files_encryption/lib/keymanager.php
@@ -459,13 +459,17 @@ class Keymanager {
 			\OCP\Util::writeLog('files_encryption', 'delAllShareKeys: delete share keys: ' . $baseDir . $filePath, \OCP\Util::DEBUG);
 			$result = $view->unlink($baseDir . $filePath);
 		} else {
-			$parentDir = dirname($baseDir . $filePath);
-			$filename = pathinfo($filePath, PATHINFO_BASENAME);
-			foreach($view->getDirectoryContent($parentDir) as $content) {
-				$path = $content['path'];
-				if (self::getFilenameFromShareKey($content['name'])  === $filename) {
-					\OCP\Util::writeLog('files_encryption', 'dellAllShareKeys: delete share keys: ' . '/' . $userId . '/' . $path, \OCP\Util::DEBUG);
-					$result &= $view->unlink('/' . $userId . '/' . $path);
+			$sharingEnabled = \OCP\Share::isEnabled();
+			$users = $util->getSharingUsersArray($sharingEnabled, $filePath);
+			foreach($users as $user) {
+				$keyName = $baseDir . $filePath . '.' . $user . '.shareKey';
+				if ($view->file_exists($keyName)) {
+					\OCP\Util::writeLog(
+						'files_encryption',
+						'dellAllShareKeys: delete share keys: "' . $keyName . '"',
+						\OCP\Util::DEBUG
+					);
+					$result &= $view->unlink($keyName);
 				}
 			}
 		}
@@ -539,17 +543,20 @@ class Keymanager {
 					if ($view->is_dir($dir . '/' . $file)) {
 						self::recursiveDelShareKeys($dir . '/' . $file, $userIds, $owner, $view);
 					} else {
-						$realFile = $realFileDir . self::getFilenameFromShareKey($file);
 						foreach ($userIds as $userId) {
-							if (preg_match("/(.*)." . $userId . ".shareKey/", $file)) {
-								if ($userId === $owner &&
-										$view->file_exists($realFile)) {
-									\OCP\Util::writeLog('files_encryption', 'original file still exists, keep owners share key!', \OCP\Util::ERROR);
-									continue;
-								}
-								\OCP\Util::writeLog('files_encryption', 'recursiveDelShareKey: delete share key: ' . $file, \OCP\Util::DEBUG);
-								$view->unlink($dir . '/' . $file);
+							$fileNameFromShareKey = self::getFilenameFromShareKey($file, $userId);
+							if (!$fileNameFromShareKey) {
+								continue;
 							}
+							$realFile = $realFileDir . $fileNameFromShareKey;
+
+							if ($userId === $owner &&
+									$view->file_exists($realFile)) {
+								\OCP\Util::writeLog('files_encryption', 'original file still exists, keep owners share key!', \OCP\Util::ERROR);
+								continue;
+							}
+							\OCP\Util::writeLog('files_encryption', 'recursiveDelShareKey: delete share key: ' . $file, \OCP\Util::DEBUG);
+							$view->unlink($dir . '/' . $file);
 						}
 					}
 				}
@@ -591,16 +598,19 @@ class Keymanager {
 	/**
 	 * extract filename from share key name
 	 * @param string $shareKey (filename.userid.sharekey)
+	 * @param string $userId
 	 * @return string|false filename or false
 	 */
-	protected static function getFilenameFromShareKey($shareKey) {
-		$parts = explode('.', $shareKey);
+	protected static function getFilenameFromShareKey($shareKey, $userId) {
+		$expectedSuffix = '.' . $userId . '.' . 'shareKey';
+		$suffixLen = strlen($expectedSuffix);
 
-		$filename = false;
-		if(count($parts) > 2) {
-			$filename = implode('.', array_slice($parts, 0, count($parts)-2));
+		$suffix = substr($shareKey, -$suffixLen);
+
+		if ($suffix !== $expectedSuffix) {
+			return false;
 		}
 
-		return $filename;
+		return substr($shareKey, 0, -$suffixLen);
 	}
 }