Support for CORS on OCS and Webdav APIs + domain whitelisting

apps/dav/lib/Connector/Sabre/CorsPlugin.php

@@ -0,0 +1,109 @@
+<?php
+/**
+ * @author Noveen Sachdeva <noveen.sachdeva@research.iiit.ac.in>
+ *
+ * @copyright Copyright (c) 2017, ownCloud GmbH
+ * @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\DAV\Connector\Sabre;
+
+use Sabre\HTTP\ResponseInterface;
+use Sabre\HTTP\RequestInterface;
+
+/**
+ * Class CorsPlugin is a plugin which adds CORS headers to the responses
+ */
+class CorsPlugin extends \Sabre\DAV\ServerPlugin {
+
+	/**
+	 * Reference to main server object
+	 *
+	 * @var \Sabre\DAV\Server
+	 */
+	private $server;
+
+	/**
+	 * Reference to logged in user's session
+	 *
+	 * @var \OCP\IUserSession
+	 */
+	private $userSession;
+
+	/**
+	 * @param \OCP\IUserSession $userSession
+	 */
+	public function __construct(\OCP\IUserSession $userSession) {
+		$this->userSession = $userSession;
+		$this->extraHeaders['Access-Control-Allow-Headers'] = ["X-OC-Mtime", "OC-Checksum", "OC-Total-Length", "Depth", "Destination", "Overwrite"];
+		$this->extraHeaders['Access-Control-Allow-Methods'] = ["MOVE", "COPY"];
+	}
+
+	/**
+	 * This initializes the plugin.
+	 *
+	 * This function is called by \Sabre\DAV\Server, after
+	 * addPlugin is called.
+	 *
+	 * This method should set up the required event subscriptions.
+	 *
+	 * @param \Sabre\DAV\Server $server
+	 * @return void
+	 */
+	public function initialize(\Sabre\DAV\Server $server) {
+		$this->server = $server;
+
+		$this->server->on('beforeMethod', [$this, 'setCorsHeaders']);
+		$this->server->on('beforeMethod:OPTIONS', [$this, 'setOptionsRequestHeaders']);
+	}
+
+	/**
+	 * This method sets the cors headers for all requests
+	 *
+	 * @return void
+	 */
+	public function setCorsHeaders(RequestInterface $request, ResponseInterface $response) {
+		if ($request->getHeader('origin') !== null && !is_null($this->userSession->getUser())) {
+			$requesterDomain = $request->getHeader('origin');
+			$userId = $this->userSession->getUser()->getUID();
+			$response = \OC_Response::setCorsHeaders($userId, $requesterDomain, $response, null, $this->extraHeaders);
+		}
+	}
+
+	/**
+	 * Handles the OPTIONS request
+	 *
+	 * @param RequestInterface $request
+	 * @param ResponseInterface $response
+	 *
+	 * @return false
+	 */
+	public function setOptionsRequestHeaders(RequestInterface $request, ResponseInterface $response) {
+		$authorization = $request->getHeader('Authorization');
+		if ($authorization === null || $authorization === '') {
+			// Set the proper response
+			$response->setStatus(200);
+			$response = \OC_Response::setOptionsRequestHeaders($response, $this->extraHeaders);
+
+			// Since All OPTIONS requests are unauthorized, we will have to return false from here
+			// If we don't return false, due to no authorization, a 401-Unauthorized will be thrown
+			// Which we don't want here
+			// Hence this sendResponse
+			$this->server->sapi->sendResponse($response);
+			return false;
+		}
+	}
+}

apps/dav/lib/Connector/Sabre/ServerFactory.php

@@ -100,6 +100,7 @@ public function createServer($baseUri,
 		$server->setBaseUri($baseUri);
 
 		// Load plugins
+		$server->addPlugin(new \OCA\DAV\Connector\Sabre\CorsPlugin($this->userSession));
 		$server->addPlugin(new \OCA\DAV\Connector\Sabre\MaintenancePlugin($this->config));
 		$server->addPlugin(new \OCA\DAV\Connector\Sabre\ValidateRequestPlugin('webdav'));
 		$server->addPlugin(new \OCA\DAV\Connector\Sabre\BlockLegacyClientPlugin($this->config));

apps/dav/lib/Server.php

@@ -32,6 +32,7 @@
 use OCA\DAV\Connector\Sabre\BlockLegacyClientPlugin;
 use OCA\DAV\Connector\Sabre\CommentPropertiesPlugin;
 use OCA\DAV\Connector\Sabre\CopyEtagHeaderPlugin;
+use OCA\DAV\Connector\Sabre\CorsPlugin;
 use OCA\DAV\Connector\Sabre\DavAclPlugin;
 use OCA\DAV\Connector\Sabre\DummyGetResponsePlugin;
 use OCA\DAV\Connector\Sabre\FakeLockerPlugin;
@@ -84,6 +85,7 @@ public function __construct(IRequest $request, $baseUri) {
 		$this->server->addPlugin(new MaintenancePlugin($config));
 		$this->server->addPlugin(new ValidateRequestPlugin('dav'));
 		$this->server->addPlugin(new BlockLegacyClientPlugin($config));
+		$this->server->addPlugin(new CorsPlugin(\OC::$server->getUserSession()));
 		$authPlugin = new Plugin();
 		$authPlugin->addBackend(new PublicAuth());
 		$this->server->addPlugin($authPlugin);

apps/provisioning_api/appinfo/routes.php

@@ -40,6 +40,7 @@
 	\OC::$server->getLogger(),
 	\OC::$server->getTwoFactorAuthManager()
 );
+
 API::register('get', '/cloud/users', [$users, 'getUsers'], 'provisioning_api', API::SUBADMIN_AUTH);
 API::register('post', '/cloud/users', [$users, 'addUser'], 'provisioning_api', API::SUBADMIN_AUTH);
 API::register('get', '/cloud/users/{userid}', [$users, 'getUser'], 'provisioning_api', API::USER_AUTH);
@@ -60,6 +61,7 @@
 	\OC::$server->getUserSession(),
 	\OC::$server->getRequest()
 );
+
 API::register('get', '/cloud/groups', [$groups, 'getGroups'], 'provisioning_api', API::SUBADMIN_AUTH);
 API::register('post', '/cloud/groups', [$groups, 'addGroup'], 'provisioning_api', API::SUBADMIN_AUTH);
 API::register('get', '/cloud/groups/{groupid}', [$groups, 'getGroup'], 'provisioning_api', API::SUBADMIN_AUTH);
@@ -68,6 +70,7 @@
 
 // Apps
 $apps = new Apps(\OC::$server->getAppManager());
+
 API::register('get', '/cloud/apps', [$apps, 'getApps'], 'provisioning_api', API::ADMIN_AUTH);
 API::register('get', '/cloud/apps/{appid}', [$apps, 'getAppInfo'], 'provisioning_api', API::ADMIN_AUTH);
 API::register('post', '/cloud/apps/{appid}', [$apps, 'enable'], 'provisioning_api', API::ADMIN_AUTH);

apps/provisioning_api/lib/Users.php

@@ -100,7 +100,7 @@ public function getUsers() {
 			}
 
 			if($offset === null) {
-				$offset = 0; 
+				$offset = 0;
 			}
 
 			$users = [];
@@ -153,7 +153,7 @@ public function addUser() {
 				return new Result(null, 106, 'no group specified (required for subadmins)');
 			}
 		}
-		
+
 		try {
 			$newUser = $this->userManager->createUser($userId, $password);
 			$this->logger->info('Successful addUser call with userid: '.$userId, ['app' => 'ocs_api']);
@@ -219,7 +219,7 @@ public function getUser($parameters) {
 		return new Result($data);
 	}
 
-	/** 
+	/**
 	 * edit users
 	 *
 	 * @param array $parameters
@@ -440,7 +440,7 @@ public function getUsersGroups($parameters) {
 				return new Result(null, 997);
 			}
 		}
-		
+
 	}
 
 	/**

core/Controller/CloudController.php

@@ -36,6 +36,7 @@ public function __construct($appName, IRequest $request) {
 	/**
 	 * @NoAdminRequired
 	 * @NoCSRFRequired
+	 * @CORS
 	 *
 	 * @return array
 	 */
@@ -49,7 +50,7 @@ public function getCapabilities() {
 			'string' => \OC_Util::getVersionString(),
 			'edition' => \OC_Util::getEditionString(),
 		];
-			
+
 		$result['capabilities'] = \OC::$server->getCapabilitiesManager()->getCapabilities();
 
 		return ['data' => $result];
@@ -58,6 +59,7 @@ public function getCapabilities() {
 	/**
 	 * @NoAdminRequired
 	 * @NoCSRFRequired
+	 * @CORS
 	 *
 	 * @return array
 	 */

lib/private/AppFramework/DependencyInjection/DIContainer.php

@@ -360,7 +360,8 @@ public function __construct($appName, $urlParams = []){
 			return new CORSMiddleware(
 				$c['Request'],
 				$c['ControllerMethodReflector'],
-				$c['OCP\IUserSession']
+				$c['OCP\IUserSession'],
+				$c['OCP\IConfig']
 			);
 		});
 

lib/private/AppFramework/Middleware/Security/CORSMiddleware.php

@@ -28,13 +28,14 @@
 use OC\AppFramework\Middleware\Security\Exceptions\SecurityException;
 use OC\AppFramework\Utility\ControllerMethodReflector;
 use OC\Authentication\Exceptions\PasswordLoginForbiddenException;
-use OC\User\Session;
 use OCP\AppFramework\Controller;
 use OCP\AppFramework\Http;
 use OCP\AppFramework\Http\JSONResponse;
 use OCP\AppFramework\Http\Response;
 use OCP\AppFramework\Middleware;
 use OCP\IRequest;
+use OCP\IUserSession;
+use OCP\IConfig;
 
 /**
  * This middleware sets the correct CORS headers on a response if the
@@ -55,21 +56,29 @@ class CORSMiddleware extends Middleware {
 	private $reflector;
 
 	/**
-	 * @var Session
+	 * @var IUserSession
 	 */
 	private $session;
 
+	/**
+	 * @var IConfig
+	 */
+	private $config;
+
 	/**
 	 * @param IRequest $request
 	 * @param ControllerMethodReflector $reflector
-	 * @param Session $session
+	 * @param IUserSession $session
+	 * @param IConfig $config
 	 */
 	public function __construct(IRequest $request,
 								ControllerMethodReflector $reflector,
-								Session $session) {
+								IUserSession $session,
+								IConfig $config) {
 		$this->request = $request;
 		$this->reflector = $reflector;
 		$this->session = $session;
+		$this->config = $config;
 	}
 
 	/**
@@ -114,9 +123,17 @@ public function beforeController($controller, $methodName){
 	 */
 	public function afterController($controller, $methodName, Response $response){
 		// only react if its a CORS request and if the request sends origin and
+		$userId = null;
+		if (!is_null($this->session->getUser())) {
+			$userId = $this->session->getUser()->getUID();
+		}
 
-		if(isset($this->request->server['HTTP_ORIGIN']) &&
-			$this->reflector->hasAnnotation('CORS')) {
+		if($this->request->getHeader("Origin") !== null &&
+			$this->reflector->hasAnnotation('CORS') && !is_null($userId)) {
+
+			$requesterDomain = $this->request->getHeader("Origin");
+
+			\OC_Response::setCorsHeaders($userId, $requesterDomain, $response, $this->config);
 
 			// allow credentials headers must not be true or CSRF is possible
 			// otherwise
@@ -128,9 +145,6 @@ public function afterController($controller, $methodName, Response $response){
 					throw new SecurityException($msg);
 				}
 			}
-
-			$origin = $this->request->server['HTTP_ORIGIN'];
-			$response->addHeader('Access-Control-Allow-Origin', $origin);
 		}
 		return $response;
 	}

lib/private/Route/Router.php

@@ -271,6 +271,41 @@ public function match($url) {
 		}
 
 		$matcher = new UrlMatcher($this->root, $this->context);
+
+		if (\OC::$server->getRequest()->getMethod() === "OPTIONS") {
+			try {
+				// Checking whether the actual request (one which OPTIONS is pre-flight for)
+				// Is actually valid
+				$requestingMethod = \OC::$server->getRequest()->getHeader('Access-Control-Request-Method');
+				$tempContext = $this->context;
+				$tempContext->setMethod($requestingMethod);
+				$tempMatcher = new UrlMatcher($this->root, $tempContext);
+				$parameters = $tempMatcher->match($url);
+
+				// Reach here if it's valid
+				$response = new \OC\OCS\Result(null, 100, 'OPTIONS request successful');
+				$response = \OC_Response::setOptionsRequestHeaders($response);
+				\OC_API::respond($response, \OC_API::requestedFormat());
+
+				// Return since no more processing for an OPTIONS request is required
+				return;
+			} catch (ResourceNotFoundException $e) {
+				if (substr($url, -1) !== '/') {
+					// We allow links to apps/files? for backwards compatibility reasons
+					// However, since Symfony does not allow empty route names, the route
+					// we need to match is '/', so we need to append the '/' here.
+					try {
+						$parameters = $matcher->match($url . '/');
+					} catch (ResourceNotFoundException $newException) {
+						// If we still didn't match a route, we throw the original exception
+						throw $e;
+					}
+				} else {
+					throw $e;
+				}
+			}
+		}
+
 		try {
 			$parameters = $matcher->match($url);
 		} catch (ResourceNotFoundException $e) {

lib/private/Settings/SettingsManager.php

@@ -46,6 +46,7 @@
 use OC\Settings\Panels\Personal\Clients;
 use OC\Settings\Panels\Personal\Version;
 use OC\Settings\Panels\Personal\Tokens;
+use OC\Settings\Panels\Personal\Cors;
 use OC\Settings\Panels\Personal\Quota;
 use OC\Settings\Panels\Admin\BackgroundJobs;
 use OC\Settings\Panels\Admin\Certificates;
@@ -246,6 +247,7 @@ private function getBuiltInPanels($type) {
 				LegacyPersonal::class,
 				Version::class,
 				Tokens::class,
+				Cors::class,
 				Quota::class
 			];
 		}
@@ -268,6 +270,10 @@ public function getBuiltInPanel($className) {
 			Clients::class => new Clients($this->config, $this->defaults),
 			Version::class => new Version(),
 			Tokens::class => new Tokens(),
+			Cors::class => new Cors(
+				$this->userSession,
+				$this->urlGenerator,
+				$this->config),
 			Quota::class => new Quota($this->helper),
 			// Admin
 			BackgroundJobs::class => new BackgroundJobs($this->config),