Add "Global Auth" option to external storage

This adds the "Global Auth" option to the external storage implementation, it is basically done by reverting c2c6caee93c491de9fa9a2e7c2eea036f4974e61 from https://github.com/owncloud/core/pull/22468.

This was taken from owncloud/core which is AGPL licensed. Commited with "icewind@owncloud.com" to keep the license header signature in sync.

![2016-06-21_14-01-06](https://cloud.githubusercontent.com/assets/878997/16228662/9c243136-37b8-11e6-9700-c1076ddb3d17.png)

3 files changed, 108 insertions, 1 deletions

diff --git a/apps/files_external/lib/AppInfo/Application.php b/apps/files_external/lib/AppInfo/Application.php
index f78411038fa..ee773d03d8c 100644
--- a/apps/files_external/lib/AppInfo/Application.php
+++ b/apps/files_external/lib/AppInfo/Application.php
@@ -112,6 +112,7 @@ class Application extends App implements IBackendProvider, IAuthMechanismProvide
 			// AuthMechanism::SCHEME_PASSWORD mechanisms
 			$container->query('OCA\Files_External\Lib\Auth\Password\Password'),
 			$container->query('OCA\Files_External\Lib\Auth\Password\SessionCredentials'),
+			$container->query('OCA\Files_External\Lib\Auth\Password\GlobalAuth'),
 
 			// AuthMechanism::SCHEME_OAUTH1 mechanisms
 			$container->query('OCA\Files_External\Lib\Auth\OAuth1\OAuth1'),
diff --git a/apps/files_external/lib/Controller/AjaxController.php b/apps/files_external/lib/Controller/AjaxController.php
index c3df3fa8522..8dcfb2a47eb 100644
--- a/apps/files_external/lib/Controller/AjaxController.php
+++ b/apps/files_external/lib/Controller/AjaxController.php
@@ -24,6 +24,7 @@
 
 namespace OCA\Files_External\Controller;
 
+use OCA\Files_External\Lib\Auth\Password\GlobalAuth;
 use OCP\AppFramework\Controller;
 use OCP\IRequest;
 use OCP\AppFramework\Http\JSONResponse;
@@ -32,10 +33,16 @@ use OCA\Files_External\Lib\Auth\PublicKey\RSA;
 class AjaxController extends Controller {
 	/** @var RSA */
 	private $rsaMechanism;
+	/** @var GlobalAuth  */
+	private $globalAuth;
 
-	public function __construct($appName, IRequest $request, RSA $rsaMechanism) {
+	public function __construct($appName,
+								IRequest $request,
+								RSA $rsaMechanism,
+								GlobalAuth $globalAuth) {
 		parent::__construct($appName, $request);
 		$this->rsaMechanism = $rsaMechanism;
+		$this->globalAuth = $globalAuth;
 	}
 
 	private function generateSshKeys() {
@@ -61,4 +68,15 @@ class AjaxController extends Controller {
 			'status' => 'success'
 		));
 	}
+
+	/**
+	 * @param string $uid
+	 * @param string $user
+	 * @param string $password
+	 * @return bool
+	 */
+	public function saveGlobalCredentials($uid, $user, $password) {
+		$this->globalAuth->saveAuth($uid, $user, $password);
+		return true;
+	}
 }
diff --git a/apps/files_external/lib/Lib/Auth/Password/GlobalAuth.php b/apps/files_external/lib/Lib/Auth/Password/GlobalAuth.php
new file mode 100644
index 00000000000..5fa4dc5d1d4
--- /dev/null
+++ b/apps/files_external/lib/Lib/Auth/Password/GlobalAuth.php
@@ -0,0 +1,88 @@
+<?php
+/**
+ * @author Robin Appelman <icewind@owncloud.com>
+ *
+ * @copyright Copyright (c) 2015, ownCloud, Inc.
+ * @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\Files_External\Lib\Auth\Password;
+
+use OCA\Files_External\Service\BackendService;
+use OCP\IL10N;
+use OCP\IUser;
+use OCA\Files_External\Lib\Auth\AuthMechanism;
+use OCA\Files_External\Lib\StorageConfig;
+use OCP\Security\ICredentialsManager;
+use OCP\Files\Storage;
+use OCA\Files_External\Lib\InsufficientDataForMeaningfulAnswerException;
+
+/**
+ * Global Username and Password
+ */
+class GlobalAuth extends AuthMechanism {
+
+	const CREDENTIALS_IDENTIFIER = 'password::global';
+
+	/** @var ICredentialsManager */
+	protected $credentialsManager;
+
+	public function __construct(IL10N $l, ICredentialsManager $credentialsManager) {
+		$this->credentialsManager = $credentialsManager;
+
+		$this
+			->setIdentifier('password::global')
+			->setVisibility(BackendService::VISIBILITY_DEFAULT)
+			->setScheme(self::SCHEME_PASSWORD)
+			->setText($l->t('Global Credentials'));
+	}
+
+	public function getAuth($uid) {
+		$auth = $this->credentialsManager->retrieve($uid, self::CREDENTIALS_IDENTIFIER);
+		if (!is_array($auth)) {
+			return [
+				'user' => '',
+				'password' => ''
+			];
+		} else {
+			return $auth;
+		}
+	}
+
+	public function saveAuth($uid, $user, $password) {
+		$this->credentialsManager->store($uid, self::CREDENTIALS_IDENTIFIER, [
+			'user' => $user,
+			'password' => $password
+		]);
+	}
+
+	public function manipulateStorageConfig(StorageConfig &$storage, IUser $user = null) {
+		if ($storage->getType() === StorageConfig::MOUNT_TYPE_ADMIN) {
+			$uid = '';
+		} elseif (is_null($user)) {
+			throw new InsufficientDataForMeaningfulAnswerException('No credentials saved');
+		} else {
+			$uid = $user->getUID();
+		}
+		$credentials = $this->credentialsManager->retrieve($uid, self::CREDENTIALS_IDENTIFIER);
+
+		if (is_array($credentials)) {
+			$storage->setBackendOption('user', $credentials['user']);
+			$storage->setBackendOption('password', $credentials['password']);
+		}
+	}
+
+}