create basic interfaces and wrapper to make encryption more modular

diff --git a/lib/private/encryption/keystorage.php b/lib/private/encryption/keystorage.php
new file mode 100644 (file)
index 0000000..5b56f6a
--- /dev/null
+++ b/lib/private/encryption/keystorage.php
@@ -0,0 +1,223 @@
+<?php
+
+/**
+ * ownCloud
+ *
+ * @copyright (C) 2015 ownCloud, Inc.
+ *
+ * @author Bjoern Schiessle <schiessle@owncloud.com>
+ *
+ * This library is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU AFFERO GENERAL PUBLIC LICENSE
+ * License as published by the Free Software Foundation; either
+ * version 3 of the License, or any later version.
+ *
+ * This library 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 library.  If not, see <http://www.gnu.org/licenses/>.
+ */
+
+namespace OC\Encryption;
+
+class KeyStorage implements \OCP\Encryption\IKeyStorage {
+
+       /** @var \OC\Files\View */
+       private $view;
+
+       /** @var \OC\Encryption\Util */
+       private $util;
+
+       // base dir where all the file related keys are stored
+       private static $keys_base_dir = '/files_encryption/keys/';
+       private static $encryption_base_dir = '/files_encryption';
+
+       private static $key_cache = array(); // cache keys
+
+       /**
+        * @param \OC\Files\View $view
+        * @param \OC\Encryption\Util $util
+        */
+       public function __construct(\OC\Files\View $view, \OC\Encryption\Util $util) {
+               $this->view = $view;
+               $this->util = $util;
+       }
+
+       /**
+        * get user specific key
+        *
+        * @param string $uid ID if the user for whom we want the key
+        * @param string $keyid id of the key
+        *
+        * @return mixed key
+        */
+       public function getUserKey($uid, $keyid) {
+               $path = '/' . $uid . self::$encryption_base_dir . '/' . $uid . '.' . $keyid;
+               return $this->getKey($path);
+
+       }
+
+       /**
+        * get file specific key
+        *
+        * @param string $path path to file
+        * @param string $keyId id of the key
+        *
+        * @return mixed key
+        */
+       public function getFileKey($path, $keyId) {
+               $keyDir = $this->getFileKeyDir($path);
+               return $this->getKey($keyDir . $keyId);
+       }
+
+       /**
+        * get system-wide encryption keys not related to a specific user,
+        * e.g something like a key for public link shares
+        *
+        * @param string $keyId id of the key
+        *
+        * @return mixed key
+        */
+       public function getSystemUserKey($keyId) {
+               $path = '/' . self::$encryption_base_dir . '/' . $keyId;
+               return $this->getKey($path);
+       }
+
+       /**
+        * set user specific key
+        *
+        * @param string $uid ID if the user for whom we want the key
+        * @param string $keyId id of the key
+        * @param mixed $key
+        */
+       public function setUserKey($uid, $keyId, $key) {
+               $path = '/' . $uid . self::$encryption_base_dir . '/' . $uid . '.' . $keyId;
+               return $this->setKey($path, $key);
+       }
+
+       /**
+        * set file specific key
+        *
+        * @param string $path path to file
+        * @param string $keyId id of the key
+        * @param mixed $key
+        */
+       public function setFileKey($path, $keyId, $key) {
+               $keyDir = $this->getFileKeyDir($path);
+               return $this->setKey($keyDir . $keyId, $key);
+       }
+
+       /**
+        * set system-wide encryption keys not related to a specific user,
+        * e.g something like a key for public link shares
+        *
+        * @param string $keyId id of the key
+        * @param mixed $key
+        *
+        * @return mixed key
+        */
+       public function setSystemUserKey($keyId, $key) {
+               $path = '/' . self::$encryption_base_dir . '/' . $keyId;
+               return $this->setKey($path, $key);
+       }
+
+
+       /**
+        * read key from hard disk
+        *
+        * @param string $path to key
+        * @return string
+        */
+       private function getKey($path) {
+
+               $key = '';
+
+               if (isset(self::$key_cache[$path])) {
+                       $key =  self::$key_cache[$path];
+               } else {
+
+                       /** @var \OCP\Files\Storage $storage */
+                       list($storage, $internalPath) = $this->view->resolvePath($path);
+
+                       if ($storage->file_exists($internalPath)) {
+                               $key = $storage->file_get_contents($internalPath);
+                               self::$key_cache[$path] = $key;
+                       }
+
+               }
+
+               return $key;
+       }
+
+       /**
+        * write key to disk
+        *
+        *
+        * @param string $path path to key directory
+        * @param string $key key
+        * @return bool
+        */
+       private function setKey($path, $key) {
+               $this->keySetPreparation(dirname($path));
+
+               /** @var \OCP\Files\Storage $storage */
+               list($storage, $internalPath) = \OC\Files\Filesystem::resolvePath($path);
+               $result = $storage->file_put_contents($internalPath, $key);
+
+               if (is_int($result) && $result > 0) {
+                       self::$key_cache[$path] = $key;
+                       return true;
+               }
+
+               return false;
+       }
+
+       /**
+        * get path to key folder for a given file
+        *
+        * @param string $path path to the file, relative to the users file directory
+        * @return string
+        */
+       private function getFileKeyDir($path) {
+
+               if ($this->view->is_dir('/' . \OCP\User::getUser() . '/' . $path)) {
+                       throw new Exception\EncryptionException('file was expected but directoy was given', Exception\EncryptionException::GENERIC);
+               }
+
+               list($owner, $filename) = $this->util->getUidAndFilename($path);
+               $filename = $this->util->stripPartialFileExtension($filename);
+               $filePath_f = ltrim($filename, '/');
+
+               // in case of system wide mount points the keys are stored directly in the data directory
+               if ($this->util->isSystemWideMountPoint($filename)) {
+                       $keyPath = self::$keys_base_dir . $filePath_f . '/';
+               } else {
+                       $keyPath = '/' . $owner . self::$keys_base_dir . $filePath_f . '/';
+               }
+
+               return $keyPath;
+       }
+
+       /**
+        * Make preparations to filesystem for saving a keyfile
+        *
+        * @param string $path relative to the views root
+        */
+       protected function keySetPreparation($path) {
+               // If the file resides within a subdirectory, create it
+               if (!$this->view->file_exists($path)) {
+                       $sub_dirs = explode('/', $path);
+                       $dir = '';
+                       foreach ($sub_dirs as $sub_dir) {
+                               $dir .= '/' . $sub_dir;
+                               if (!$this->view->is_dir($dir)) {
+                                       $this->view->mkdir($dir);
+                               }
+                       }
+               }
+       }
+
+}

diff --git a/lib/public/encryption/ikeystorage.php b/lib/public/encryption/ikeystorage.php
new file mode 100644 (file)
index 0000000..cf94d56
--- /dev/null
+++ b/lib/public/encryption/ikeystorage.php
@@ -0,0 +1,87 @@
+<?php
+
+/**
+ * ownCloud
+ *
+ * @copyright (C) 2015 ownCloud, Inc.
+ *
+ * @author Bjoern Schiessle <schiessle@owncloud.com>
+ *
+ * This library is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU AFFERO GENERAL PUBLIC LICENSE
+ * License as published by the Free Software Foundation; either
+ * version 3 of the License, or any later version.
+ *
+ * This library 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 library.  If not, see <http://www.gnu.org/licenses/>.
+ */
+
+namespace OCP\Encryption;
+
+interface IKeyStorage {
+
+       /**
+        * get user specific key
+        *
+        * @param string $uid ID if the user for whom we want the key
+        * @param string $keyid id of the key
+        *
+        * @return mixed key
+        */
+       public function getUserKey($uid, $keyid);
+
+       /**
+        * get file specific key
+        *
+        * @param string $path path to file
+        * @param string $keyid id of the key
+        *
+        * @return mixed key
+        */
+       public function getFileKey($path, $keyid);
+
+       /**
+        * get system-wide encryption keys not related to a specific user,
+        * e.g something like a key for public link shares
+        *
+        * @param string $keyid id of the key
+        *
+        * @return mixed key
+        */
+       public function getSystemUserKey($uid, $keyid);
+
+       /**
+        * set user specific key
+        *
+        * @param string $uid ID if the user for whom we want the key
+        * @param string $keyid id of the key
+        * @param mixed $key
+        */
+       public function setUserKey($uid, $keyid, $key);
+
+       /**
+        * set file specific key
+        *
+        * @param string $path path to file
+        * @param string $keyid id of the key
+        * @param mixed $key
+        */
+       public function setFileKey($path, $keyid, $key);
+
+       /**
+        * set system-wide encryption keys not related to a specific user,
+        * e.g something like a key for public link shares
+        *
+        * @param string $keyid id of the key
+        * @param mixed $key
+        *
+        * @return mixed key
+        */
+       public function setSystemUserKey($uid, $keyid, $key);
+
+}