Ticket #20276: 20276.backpress.diff

includes/class.wp-auth.php

@@ -148 +148 @@
          */
         function validate_auth_cookie( $cookie = null, $scheme = 'auth' )
         {
-                if ( empty( $cookie ) ) {
-                        foreach ( $this->cookies[$scheme] as $_scheme_cookie ) {
-                                // Take the first cookie of type scheme that exists
-                                if ( !empty( $_COOKIE[$_scheme_cookie['name']] ) ) {
-                                        $cookie = $_COOKIE[$_scheme_cookie['name']];
-                                        break;
-                                }
-                        }
-                }
-                
-                if ( !$cookie ) {
+                if ( ! $cookie_elements = $this->parse_auth_cookie( $cookie, $scheme ) ) {
+                        do_action( 'auth_cookie_malformed', $cookie );
                         return false;
                 }
+                extract( $cookie_elements );
 
-                $cookie_elements = explode( '|', $cookie );
-                if ( count( $cookie_elements ) != 3 ) {
-                        do_action( 'auth_cookie_malformed', $cookie, $scheme );
-                        return false;
-                }
-
-                list( $username, $expiration, $hmac ) = $cookie_elements;
-
                 $expired = $expiration;
 
                 // Allow a grace period for POST and AJAX requests
@@ -193 +177 @@
                         $pass_frag = substr( $user->user_pass, 8, 4 );
                 }
 
-                $key  = call_user_func( backpress_get_option( 'hash_function_name' ), $username . $pass_frag . '|' . $expiration, $scheme );
-                $hash = hash_hmac( 'md5', $username . '|' . $expiration, $key );
+                $key  = call_user_func( backpress_get_option( 'hash_function_name' ), $username . '|' . $pass_frag . '|' . $expiration . '|' . $token, $scheme );
+                $hash = hash_hmac( 'md5', $username . '|' . $expiration . '|' . $token, $key );
         
                 if ( $hmac != $hash ) {
                         do_action( 'auth_cookie_bad_hash', $cookie_elements );
@@ -201 +185 @@
                         return false;
                 }
 
+                if ( ! $this->verify_session_token( $user, $token ) ) {
+                        do_action( 'auth_cookie_bad_session_token', $cookie_elements );
+                        return false;
+                }
+
                 do_action( 'auth_cookie_valid', $cookie_elements, $user );
 
                 return $user->ID;
@@ -215 +204 @@
          *
          * @param int $user_id User ID
          * @param int $expiration Cookie expiration in seconds
+         * @param string $scheme The cookie scheme to use: auth, secure_auth, or logged_in
+         * @param string $token User's session token to use for this cookie
          * @return string Authentication cookie contents
          */
-        function generate_auth_cookie( $user_id, $expiration, $scheme = 'auth' )
+        function generate_auth_cookie( $user_id, $expiration, $scheme = 'auth', $token = '' )
         {
                 $user = $this->users->get_user( $user_id );
                 if ( !$user || is_wp_error( $user ) ) {
@@ -224 +215 @@
                         return $user;
                 }
 
+                if ( empty( $token ) )
+                        $token = $this->create_session_token( $user, $expiration );
+
                 $pass_frag = '';
                 if ( 1 < WP_AUTH_COOKIE_VERSION ) {
                         $pass_frag = substr( $user->user_pass, 8, 4 );
                 }
 
-                $key  = call_user_func( backpress_get_option( 'hash_function_name' ), $user->user_login . $pass_frag . '|' . $expiration, $scheme );
-                $hash = hash_hmac('md5', $user->user_login . '|' . $expiration, $key);
+                $key  = call_user_func( backpress_get_option( 'hash_function_name' ), $user->user_login . '|' . $pass_frag . '|' . $expiration . '|' . $token, $scheme );
+                $hash = hash_hmac('md5', $user->user_login . '|' . $expiration . '|' . $token, $key);
 
-                $cookie = $user->user_login . '|' . $expiration . '|' . $hash;
+                $cookie = $user->user_login . '|' . $expiration . '|' . $token . '|' . $hash;
 
                 return apply_filters( 'auth_cookie', $cookie, $user_id, $expiration, $scheme );
         }
@@ -264 +258 @@
 
                 $expire = absint( $expire );
 
+                $token = $this->create_session_token( $user_id, $expiration );
+
                 foreach ( $this->cookies[$scheme] as $_cookie ) {
-                        $cookie = $this->generate_auth_cookie( $user_id, $expiration, $scheme );
+                        $cookie = $this->generate_auth_cookie( $user_id, $expiration, $scheme, $token );
                         if ( is_wp_error( $cookie ) ) {
                                 return $cookie;
                         }
@@ -302 +298 @@
                 }
                 unset( $_scheme, $_scheme_cookies );
         }
+
+        function create_session_token( $user, $expiration ) {
+                if ( ! is_object( $user ) )
+                        $user = $this->users->get_user( $user );
+
+                $sessions = ! empty( $user->session_tokens ) ? $user->session_tokens : array();
+
+                $time = time();
+                foreach ( $sessions as $v => $e ) {
+                        if ( $e < $time )
+                                unset( $sessions[ $v ] );
+                }
+
+                $token = WP_Pass::generate_password( 40, false );
+                $verifier = hash( 'sha256', $token );
+                $sessions[ $verifier ] = $expiration;
+
+                $GLOBALS['wp_users_object']->update_meta( array( 'id' => $user->ID, 'meta_key' => 'session_tokens', 'meta_value' => $sessions ) );
+
+                return $token;
+        }
+
+        function verify_session_token( $user, $token ) {
+                $verifier = hash( 'sha256', $token );
+                return isset( $user->session_tokens[ $verifier ] ) && $user->session_tokens[ $verifier ] >= time();
+        }
+
+        function destroy_current_session() {
+                $cookie = $this->parse_auth_cookie( '', 'logged_in' );
+                if ( ! empty( $cookie['token'] ) ) {
+                        $user = $this->get_current_user();
+                        $verifier = hash( 'sha256', $cookie['token'] );
+                        $sessions = ! empty( $user->session_tokens ) ? $user->session_tokens : array();
+                        unset( $sessions[ $verifier ] );
+
+                        $time = time();
+                        foreach ( $sessions as $v => $e ) {
+                                if ( $e < $time )
+                                        unset( $sessions[ $v ] );
+                        }
+
+                        $GLOBALS['wp_users_object']->update_meta( array( 'id' => $user->ID, 'meta_key' => 'session_tokens', 'meta_value' => $sessions ) );
+                }
+        }
+
+        function parse_auth_cookie( $cookie = '', $scheme = 'auth' ) {
+                if ( empty( $cookie ) ) {
+                        foreach ( $this->cookies[$scheme] as $_scheme_cookie ) {
+                                // Take the first cookie of type scheme that exists
+                                if ( !empty( $_COOKIE[$_scheme_cookie['name']] ) ) {
+                                        $cookie = $_COOKIE[$_scheme_cookie['name']];
+                                        break;
+                                }
+                        }
+                }
+                
+                if ( ! $cookie )
+                        return false;
+
+                $cookie_elements = explode( '|', $cookie );
+                if ( count( $cookie_elements ) != 4 )
+                        return false;
+
+                list( $username, $expiration, $token, $hmac ) = $cookie_elements;
+                return compact( 'username', 'expiration', 'token', 'hmac' );
+        }
 }