fix bug #127: update session class

3 files changed, 223 insertions, 71 deletions

diff --git a/inc/3rdparty/Session.class.php b/inc/3rdparty/Session.class.php
index 3162f507..08126bad 100644
--- a/inc/3rdparty/Session.class.php
+++ b/inc/3rdparty/Session.class.php
@@ -1,136 +1,279 @@
 <?php
 /**
  * Session management class
+ *
  * http://www.developpez.net/forums/d51943/php/langage/sessions/
  * http://sebsauvage.net/wiki/doku.php?id=php:session
  * http://sebsauvage.net/wiki/doku.php?id=php:shaarli
- *
+ * 
  * Features:
  * - Everything is stored on server-side (we do not trust client-side data,
  *   such as cookie expiration)
- * - IP addresses + user agent are checked on each access to prevent session
- *   cookie hijacking (such as Firesheep)
+ * - IP addresses are checked on each access to prevent session cookie hijacking
+ *   (such as Firesheep)
  * - Session expires on user inactivity (Session expiration date is
  *   automatically updated everytime the user accesses a page.)
  * - A unique secret key is generated on server-side for this session
- *   (and never sent over the wire) which can be used
- *   to sign forms (HMAC) (See $_SESSION['uid'] )
- * - Token management to prevent XSRF attacks.
+ *   (and never sent over the wire) which can be used to sign forms (HMAC)
+ *   (See $_SESSION['uid'])
+ * - Token management to prevent XSRF attacks
+ * - Brute force protection with ban management
  *
- * TODO:
- * - log login fail
- * - prevent brute force (ban IP)
+ * TODOs
+ * - Replace globals with variables in Session class
  *
- * HOWTOUSE:
- * - Just call Session::init(); to initialize session and
- *   check if connected with Session::isLogged()
+ * How to use:
+ * - http://tontof.net/kriss/php5/session
  */
-
 class Session
 {
+    // Personnalize PHP session name
+    public static $sessionName = '';
     // If the user does not access any page within this time,
-    // his/her session is considered expired (in seconds).
-    public static $inactivity_timeout = 3600;
-    private static $_instance;
+    // his/her session is considered expired (3600 sec. = 1 hour)
+    public static $inactivityTimeout = 3600;
+    // If you get disconnected often or if your IP address changes often.
+    // Let you disable session cookie hijacking protection
+    public static $disableSessionProtection = false;
+    // Ban IP after this many failures.
+    public static $banAfter = 4;
+    // Ban duration for IP address after login failures (in seconds).
+    // (1800 sec. = 30 minutes)
+    public static $banDuration = 1800;
+    // File storage for failures and bans. If empty, no ban management.
+    public static $banFile = '';
 
-    // constructor
-    private function __construct()
+    /**
+     * Initialize session
+     */
+    public static function init()
     {
+        // Force cookie path (but do not change lifetime)
+        $cookie = session_get_cookie_params();
+        // Default cookie expiration and path.
+        $cookiedir = '';
+        if (dirname($_SERVER['SCRIPT_NAME'])!='/') {
+            $cookiedir = dirname($_SERVER["SCRIPT_NAME"]).'/';
+        }
+        $ssl = false;
+        if (isset($_SERVER["HTTPS"]) && $_SERVER["HTTPS"] == "on") {
+            $ssl = true;
+        }
+        session_set_cookie_params($cookie['lifetime'], $cookiedir, $_SERVER['HTTP_HOST'], $ssl);
         // Use cookies to store session.
         ini_set('session.use_cookies', 1);
         // Force cookies for session  (phpsessionID forbidden in URL)
         ini_set('session.use_only_cookies', 1);
-        if (!session_id()){
+        if (!session_id()) {
             // Prevent php to use sessionID in URL if cookies are disabled.
             ini_set('session.use_trans_sid', false);
-            session_start('poche');
+            if (!empty(self::$sessionName)) {
+                session_name(self::$sessionName);
+            }
+            session_start();
         }
     }
 
-    // initialize session
-    public static function init()
+    /**
+     * Returns the IP address
+     * (Used to prevent session cookie hijacking.)
+     *
+     * @return string IP addresses
+     */
+    private static function _allIPs()
     {
-        if (!isset(self::$_instance)) {
-            self::$_instance = new Session();
-        }
-    }
+        $ip = $_SERVER["REMOTE_ADDR"];
+        $ip.= isset($_SERVER['HTTP_X_FORWARDED_FOR']) ? '_'.$_SERVER['HTTP_X_FORWARDED_FOR'] : '';
+        $ip.= isset($_SERVER['HTTP_CLIENT_IP']) ? '_'.$_SERVER['HTTP_CLIENT_IP'] : '';
 
-    // Returns the IP address, user agent and language of the client
-    // (Used to prevent session cookie hijacking.)
-    private static function _allInfos()
-    {
-        $infos = $_SERVER["REMOTE_ADDR"];
-        if (isset($_SERVER['HTTP_X_FORWARDED_FOR'])) {
-            $infos.=$_SERVER['HTTP_X_FORWARDED_FOR'];
-        }
-        if (isset($_SERVER['HTTP_CLIENT_IP'])) {
-            $infos.='_'.$_SERVER['HTTP_CLIENT_IP'];
-        }
-        $infos.='_'.$_SERVER['HTTP_USER_AGENT'];
-        $infos.='_'.$_SERVER['HTTP_ACCEPT_LANGUAGE'];
-        return sha1($infos);
+        return $ip;
     }
 
-    // Check that user/password is correct and init some SESSION variables.
-    public static function login($login,$password,$login_test,$password_test,
-                                 $pValues = array())
+    /**
+     * Check that user/password is correct and then init some SESSION variables.
+     *
+     * @param string $login        Login reference
+     * @param string $password     Password reference
+     * @param string $loginTest    Login to compare with login reference
+     * @param string $passwordTest Password to compare with password reference
+     * @param array  $pValues      Array of variables to store in SESSION
+     *
+     * @return true|false          True if login and password are correct, false
+     *                             otherwise
+     */
+    public static function login (
+        $login,
+        $password,
+        $loginTest,
+        $passwordTest,
+        $pValues = array())
     {
-        foreach ($pValues as $key => $value) {
-            $_SESSION[$key] = $value;
-        }
-        if ($login==$login_test && $password==$password_test){
-            // generate unique random number to sign forms (HMAC)
-            $_SESSION['uid'] = sha1(uniqid('',true).'_'.mt_rand());
-            $_SESSION['info']=Session::_allInfos();
-            $_SESSION['username']=$login;
-            // Set session expiration.
-            $_SESSION['expires_on']=time()+Session::$inactivity_timeout;
-            return true;
+        self::banInit();
+        if (self::banCanLogin()) {
+            if ($login === $loginTest && $password === $passwordTest) {
+                self::banLoginOk();
+                // Generate unique random number to sign forms (HMAC)
+                $_SESSION['uid'] = sha1(uniqid('', true).'_'.mt_rand());
+                $_SESSION['ip'] = self::_allIPs();
+                $_SESSION['username'] = $login;
+                // Set session expiration.
+                $_SESSION['expires_on'] = time() + self::$inactivityTimeout;
+
+                foreach ($pValues as $key => $value) {
+                    $_SESSION[$key] = $value;
+                }
+
+                return true;
+            }
+            self::banLoginFailed();
         }
+
         return false;
     }
 
-    // Force logout
+    /**
+     * Unset SESSION variable to force logout
+     */
     public static function logout()
     {
-        unset($_SESSION['uid'],$_SESSION['info'],$_SESSION['expires_on'],$_SESSION['tokens'], $_SESSION['login'], $_SESSION['pass'], $_SESSION['poche_user']);
+        unset($_SESSION['uid'], $_SESSION['ip'], $_SESSION['expires_on']);
     }
 
-    // Make sure user is logged in.
+    /**
+     * Make sure user is logged in.
+     *
+     * @return true|false True if user is logged in, false otherwise
+     */
     public static function isLogged()
     {
         if (!isset ($_SESSION['uid'])
-            || $_SESSION['info']!=Session::_allInfos()
-            || time()>=$_SESSION['expires_on']){
-            Session::logout();
+            || (self::$disableSessionProtection === false
+                && $_SESSION['ip'] !== self::_allIPs())
+            || time() >= $_SESSION['expires_on']) {
+            self::logout();
+
             return false;
         }
         // User accessed a page : Update his/her session expiration date.
-        $_SESSION['expires_on']=time()+Session::$inactivity_timeout;
+        $_SESSION['expires_on'] = time() + self::$inactivityTimeout;
+        if (!empty($_SESSION['longlastingsession'])) {
+                $_SESSION['expires_on'] += $_SESSION['longlastingsession'];
+        }
+
         return true;
     }
 
-    // Returns a token.
-    public static function getToken()
+    /**
+     * Create a token, store it in SESSION and return it
+     *
+     * @param string $salt to prevent birthday attack
+     *
+     * @return string Token created
+     */
+    public static function getToken($salt = '')
     {
-        if (!isset($_SESSION['tokens'])){
+        if (!isset($_SESSION['tokens'])) {
             $_SESSION['tokens']=array();
         }
         // We generate a random string and store it on the server side.
-        $rnd = sha1(uniqid('',true).'_'.mt_rand());
+        $rnd = sha1(uniqid('', true).'_'.mt_rand().$salt);
         $_SESSION['tokens'][$rnd]=1;
+
         return $rnd;
     }
 
-    // Tells if a token is ok. Using this function will destroy the token.
-    // return true if token is ok.
+    /**
+     * Tells if a token is ok. Using this function will destroy the token.
+     *
+     * @param string $token Token to test
+     *
+     * @return true|false   True if token is correct, false otherwise
+     */
     public static function isToken($token)
     {
-        if (isset($_SESSION['tokens'][$token]))
-        {
+        if (isset($_SESSION['tokens'][$token])) {
             unset($_SESSION['tokens'][$token]); // Token is used: destroy it.
+
             return true; // Token is ok.
         }
+
         return false; // Wrong token, or already used.
     }
-}
\ No newline at end of file
+
+    /**
+     * Signal a failed login. Will ban the IP if too many failures:
+     */
+    public static function banLoginFailed()
+    {
+        if (self::$banFile !== '') {
+            $ip = $_SERVER["REMOTE_ADDR"];
+            $gb = $GLOBALS['IPBANS'];
+
+            if (!isset($gb['FAILURES'][$ip])) {
+                $gb['FAILURES'][$ip] = 0;
+            }
+            $gb['FAILURES'][$ip]++;
+            if ($gb['FAILURES'][$ip] > (self::$banAfter - 1)) {
+                $gb['BANS'][$ip]= time() + self::$banDuration;
+            }
+
+            $GLOBALS['IPBANS'] = $gb;
+            file_put_contents(self::$banFile, "<?php\n\$GLOBALS['IPBANS']=".var_export($gb, true).";\n?>");
+        }
+    }
+
+    /**
+     * Signals a successful login. Resets failed login counter.
+     */
+    public static function banLoginOk()
+    {
+        if (self::$banFile !== '') {
+            $ip = $_SERVER["REMOTE_ADDR"];
+            $gb = $GLOBALS['IPBANS'];
+            unset($gb['FAILURES'][$ip]); unset($gb['BANS'][$ip]);
+            $GLOBALS['IPBANS'] = $gb;
+            file_put_contents(self::$banFile, "<?php\n\$GLOBALS['IPBANS']=".var_export($gb, true).";\n?>");
+        }
+    }
+
+    /**
+     * Ban init
+     */
+    public static function banInit()
+    {
+        if (self::$banFile !== '') {
+            if (!is_file(self::$banFile)) {
+                file_put_contents(self::$banFile, "<?php\n\$GLOBALS['IPBANS']=".var_export(array('FAILURES'=>array(), 'BANS'=>array()), true).";\n?>");
+            }
+            include self::$banFile;
+        }
+    }
+
+    /**
+     * Checks if the user CAN login. If 'true', the user can try to login.
+     *
+     * @return boolean true if user is banned, false otherwise
+     */
+    public static function banCanLogin()
+    {
+        if (self::$banFile !== '') {
+            $ip = $_SERVER["REMOTE_ADDR"];
+            $gb = $GLOBALS['IPBANS'];
+            if (isset($gb['BANS'][$ip])) {
+                // User is banned. Check if the ban has expired:
+                if ($gb['BANS'][$ip] <= time()) {
+                    // Ban expired, user can try to login again.
+                    unset($gb['FAILURES'][$ip]);
+                    unset($gb['BANS'][$ip]);
+                    file_put_contents(self::$banFile, "<?php\n\$GLOBALS['IPBANS']=".var_export($gb, true).";\n?>");
+
+                    return true; // Ban has expired, user can login.
+                }
+
+                return false; // User is banned.
+            }
+        }
+
+        return true; // User is not banned.
+    }
+}
diff --git a/inc/poche/Poche.class.php b/inc/poche/Poche.class.php
index 9db4a034..2f0f7038 100644
--- a/inc/poche/Poche.class.php
+++ b/inc/poche/Poche.class.php
@@ -93,6 +93,7 @@ class Poche
     private function init() 
     {
         Tools::initPhp();
+        Session::$sessionName = 'poche'; 
         Session::init();
 
         if (isset($_SESSION['poche_user']) && $_SESSION['poche_user'] != array()) {
diff --git a/inc/poche/config.inc.php b/inc/poche/config.inc.php
index aaa26af8..9247c292 100755
--- a/inc/poche/config.inc.php
+++ b/inc/poche/config.inc.php
@@ -48,4 +48,12 @@ if (!ini_get('date.timezone') || !@date_default_timezone_set(ini_get('date.timez
     date_default_timezone_set('UTC');
 }
 
-$poche = new Poche();
\ No newline at end of file
+$poche = new Poche();
+
+#XSRF protection with token
+if (!empty($_POST)) {
+    if (!Session::isToken($_POST['token'])) {
+        die(_('Wrong token'));
+    }
+    unset($_SESSION['tokens']);
+}
\ No newline at end of file