Merge pull request #31 from visit1985/persistentcookies

reresubmit: improved persistent cookies :)

config/config.sample.php

@@ -92,6 +92,9 @@ $CONFIG = array(
 /* Loglevel to start logging at. 0=DEBUG, 1=INFO, 2=WARN, 3=ERROR (default is WARN) */
 "loglevel" => "",
 
+/* Lifetime of the remember login cookie, default is 15 days */
+"remember_login_cookie_lifetime" => 60*60*24*15,
+
 /* The directory where the user data is stored, default to data in the owncloud
  * directory. The sqlite database is also stored here, when sqlite is used.
  */

lib/base.php

@@ -264,8 +264,30 @@ class OC{
 	}
 
 	public static function initSession() {
+		// prevents javascript from accessing php session cookies
 		ini_set('session.cookie_httponly', '1;');
+
+		// (re)-initialize session
 		session_start();
+		
+		// regenerate session id periodically to avoid session fixation
+		if (!isset($_SESSION['SID_CREATED'])) {
+			$_SESSION['SID_CREATED'] = time();
+		} else if (time() - $_SESSION['SID_CREATED'] > 900) {
+			session_regenerate_id(true);
+			$_SESSION['SID_CREATED'] = time();
+		}
+
+		// session timeout
+		if (isset($_SESSION['LAST_ACTIVITY']) && (time() - $_SESSION['LAST_ACTIVITY'] > 3600)) {
+			if (isset($_COOKIE[session_name()])) {
+				setcookie(session_name(), '', time() - 42000, '/');
+			}
+			session_unset();
+			session_destroy();
+			session_start();
+		}
+		$_SESSION['LAST_ACTIVITY'] = time();
 	}
 
 	public static function init() {
@@ -453,6 +475,7 @@ class OC{
 			OC_App::loadApps();
 			OC_User::setupBackends();
 			if(isset($_GET["logout"]) and ($_GET["logout"])) {
+				OC_Preferences::deleteKey(OC_User::getUser(), 'login_token', $_COOKIE['oc_token']);
 				OC_User::logout();
 				header("Location: ".OC::$WEBROOT.'/');
 			}else{
@@ -514,6 +537,17 @@ class OC{
 		OC_Util::displayLoginPage(array_unique($error));
 	}
 
+	protected static function cleanupLoginTokens($user) {
+		$cutoff = time() - OC_Config::getValue('remember_login_cookie_lifetime', 60*60*24*15);
+		$tokens = OC_Preferences::getKeys($user, 'login_token');
+		foreach($tokens as $token) {
+			$time = OC_Preferences::getValue($user, 'login_token', $token);
+			if ($time < $cutoff) {
+				OC_Preferences::deleteKey($user, 'login_token', $token);
+			}
+		}
+	}
+
 	protected static function tryRememberLogin() {
 		if(!isset($_COOKIE["oc_remember_login"])
 			|| !isset($_COOKIE["oc_token"])
@@ -527,15 +561,30 @@ class OC{
 			OC_Log::write('core', 'Trying to login from cookie', OC_Log::DEBUG);
 		}
 		// confirm credentials in cookie
-		if(isset($_COOKIE['oc_token']) && OC_User::userExists($_COOKIE['oc_username']) &&
-			OC_Preferences::getValue($_COOKIE['oc_username'], "login", "token") === $_COOKIE['oc_token'])
-		{
-			OC_User::setUserId($_COOKIE['oc_username']);
-			OC_Util::redirectToDefaultPage();
-		}
-		else {
-			OC_User::unsetMagicInCookie();
+		if(isset($_COOKIE['oc_token']) && OC_User::userExists($_COOKIE['oc_username'])) {
+			// delete outdated cookies
+			self::cleanupLoginTokens($_COOKIE['oc_username']);
+			// get stored tokens
+			$tokens = OC_Preferences::getKeys($_COOKIE['oc_username'], 'login_token');
+			// test cookies token against stored tokens
+			if (in_array($_COOKIE['oc_token'], $tokens, true)) {
+				// replace successfully used token with a new one
+				OC_Preferences::deleteKey($_COOKIE['oc_username'], 'login_token', $_COOKIE['oc_token']);
+				$token = OC_Util::generate_random_bytes(32);
+				OC_Preferences::setValue($_COOKIE['oc_username'], 'login_token', $token, time());
+				OC_User::setMagicInCookie($_COOKIE['oc_username'], $token);
+				// login
+				OC_User::setUserId($_COOKIE['oc_username']);
+				OC_Util::redirectToDefaultPage();
+				// doesn't return
+			}
+			// if you reach this point you have changed your password 
+			// or you are an attacker
+			// we can not delete tokens here because users may reach 
+			// this point multiple times after a password change
+			OC_Log::write('core', 'Authentication cookie rejected for user '.$_COOKIE['oc_username'], OC_Log::WARN);
 		}
+		OC_User::unsetMagicInCookie();
 		return true;
 	}
 
@@ -550,12 +599,13 @@ class OC{
 		OC_User::setupBackends();
 
 		if(OC_User::login($_POST["user"], $_POST["password"])) {
+			self::cleanupLoginTokens($_POST['user']);
 			if(!empty($_POST["remember_login"])) {
 				if(defined("DEBUG") && DEBUG) {
 					OC_Log::write('core', 'Setting remember login to cookie', OC_Log::DEBUG);
 				}
-				$token = md5($_POST["user"].time().$_POST['password']);
-				OC_Preferences::setValue($_POST['user'], 'login', 'token', $token);
+				$token = OC_Util::generate_random_bytes(32);
+				OC_Preferences::setValue($_POST['user'], 'login_token', $token, time());
 				OC_User::setMagicInCookie($_POST["user"], $token);
 			}
 			else {

lib/user.php

@@ -329,6 +329,8 @@ class OC_User {
 					}
 				}
 			}
+			// invalidate all login cookies
+			OC_Preferences::deleteApp($uid, 'login_token');
 			OC_Hook::emit( "OC_User", "post_setPassword", array( "uid" => $uid, "password" => $password ));
 			return $success;
 		}
@@ -472,9 +474,10 @@ class OC_User {
 	 */
 	public static function setMagicInCookie($username, $token) {
 		$secure_cookie = OC_Config::getValue("forcessl", false);
-		setcookie("oc_username", $username, time()+60*60*24*15, '', '', $secure_cookie);
-		setcookie("oc_token", $token, time()+60*60*24*15, '', '', $secure_cookie);
-		setcookie("oc_remember_login", true, time()+60*60*24*15, '', '', $secure_cookie);
+		$expires = time() + OC_Config::getValue('remember_login_cookie_lifetime', 60*60*24*15);
+		setcookie("oc_username", $username, $expires, '', '', $secure_cookie);
+		setcookie("oc_token", $token, $expires, '', '', $secure_cookie);
+		setcookie("oc_remember_login", true, $expires, '', '', $secure_cookie);
 	}
 
 	/**