Ticket #20276: 20276.diff

src/wp-includes/pluggable.php

@@ -494 +494 @@
  * @since 2.5.0
  */
 function wp_logout() {
+        wp_destroy_current_session();
         wp_clear_auth_cookie();
         do_action('wp_logout');
 }
@@ -543 +544 @@
 
         $pass_frag = substr($user->user_pass, 8, 4);
 
-        $key = wp_hash($username . $pass_frag . '|' . $expiration, $scheme);
-        $hash = hash_hmac('md5', $username . '|' . $expiration, $key);
+        $key = wp_hash($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);
@@ -551 +552 @@
                 return false;
         }
 
+        if ( ! wp_verify_session_token( $user->ID, $token ) ) {
+                return false;
+        }
+
         if ( $expiration < time() ) // AJAX/POST grace period set above
                 $GLOBALS['login_grace_period'] = 1;
 
@@ -569 +574 @@
  *              and expiration of cookie.
  *
  * @param int $user_id User ID
+ * @param string $token User's session token to use for this cookie
  * @param int $expiration Cookie expiration in seconds
  * @param string $scheme Optional. The cookie scheme to use: auth, secure_auth, or logged_in
  * @return string Authentication cookie contents
  */
-function wp_generate_auth_cookie($user_id, $expiration, $scheme = 'auth') {
-        $user = get_userdata($user_id);
+function wp_generate_auth_cookie($user_id, $token, $expiration, $scheme = 'auth') {
+        $user = new WP_User($user_id);
+        if ( ! $user->exists() )
+                return '';
 
         $pass_frag = substr($user->user_pass, 8, 4);
 
-        $key = wp_hash($user->user_login . $pass_frag . '|' . $expiration, $scheme);
-        $hash = hash_hmac('md5', $user->user_login . '|' . $expiration, $key);
+        $key = wp_hash($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);
 }
@@ -625 +633 @@
         }
 
         $cookie_elements = explode('|', $cookie);
-        if ( count($cookie_elements) != 3 )
+        if ( count($cookie_elements) != 4 )
                 return false;
 
-        list($username, $expiration, $hmac) = $cookie_elements;
+        list($username, $expiration, $token, $hmac) = $cookie_elements;
 
-        return compact('username', 'expiration', 'hmac', 'scheme');
+        return compact('username', 'expiration', 'token', 'hmac', 'scheme');
 }
 endif;
 
@@ -646 +654 @@
  *
  * @param int $user_id User ID
  * @param bool $remember Whether to remember the user
+ * @param mixed $secure Whether the admin cookies should only be sent over HTTPS (defaults to is_ssl())
  */
 function wp_set_auth_cookie($user_id, $remember = false, $secure = '') {
         if ( $remember ) {
@@ -669 +678 @@
                 $scheme = 'auth';
         }
 
-        $auth_cookie = wp_generate_auth_cookie($user_id, $expiration, $scheme);
-        $logged_in_cookie = wp_generate_auth_cookie($user_id, $expiration, 'logged_in');
+        $token = wp_create_session_token( $user_id, $expiration );
 
+        $auth_cookie = wp_generate_auth_cookie($user_id, $token, $expiration, $scheme);
+        $logged_in_cookie = wp_generate_auth_cookie($user_id, $token, $expiration, 'logged_in');
+
         do_action('set_auth_cookie', $auth_cookie, $expire, $expiration, $user_id, $scheme);
         do_action('set_logged_in_cookie', $logged_in_cookie, $expire, $expiration, $user_id, 'logged_in');
 

src/wp-includes/user.php

@@ -1550 +1550 @@
         }
         return apply_filters( 'user_contactmethods', $user_contactmethods, $user );
 }
+
+/**
+ * Generate a cookie session identification token.
+ *
+ * A session identification token is a long, random string. It is used to
+ * link a cookie to an expiration time and to ensure that cookies become
+ * invalidated upon logout. This function generates a token and stores it
+ * as user meta with the associated expiration time.
+ *
+ * Will also remove any expired tokens from the database.
+ *
+ * @since 3.7.0
+ *
+ * @param int $user_id User to create a token for.
+ * @param int $expiration Session expiration timestamp.
+ * @return string Session identification token.
+ */
+function wp_create_session_token( $user_id, $expiration ) {
+        $sessions = get_user_meta( $user_id, 'session_tokens', true );
+        if ( ! $sessions )
+                $sessions = array();
+        $sessions = array_filter( $sessions, '_session_not_expired' );
+
+        $token = wp_generate_password( 40, false, false );
+        $verifier = hash( 'sha256', $token );
+        $sessions[$verifier] = $expiration;
+
+        update_user_meta( $user_id, 'session_tokens', $sessions );
+
+        return $token;
+}
+
+/**
+ * Validate a user's session token as authentic.
+ *
+ * Checks that the given token is present in the database and hasn't expired.
+ *
+ * @since 3.7.0
+ *
+ * @param int $user_id User to verify against.
+ * @param string $token Token to verify.
+ * @return bool Whether the token is valid for the given user.
+ */
+function wp_verify_session_token( $user_id, $token ) {
+        $sessions = get_user_meta( $user_id, 'session_tokens', true );
+        $verifier = hash( 'sha256', $token );
+        return isset( $sessions[$verifier] ) && $sessions[$verifier] >= time();
+}
+
+/**
+ * Remove the current session token from the database.
+ *
+ * Will also remove any expired tokens from the database.
+ *
+ * @since 3.7.0
+ */
+function wp_destroy_current_session() {
+        $user_id = get_current_user_id();
+        $cookie = wp_parse_auth_cookie( '', 'logged_in' );
+        if ( ! empty( $cookie['token'] ) ) {
+                $verifier = hash( 'sha256', $cookie['token'] );
+                $sessions = get_user_meta( $user_id, 'session_tokens', true );
+                unset( $sessions[$verifier] );
+                $sessions = array_filter( $sessions, '_session_not_expired' );
+                update_user_meta( $user_id, 'session_tokens', $sessions );
+        }
+}
+
+/**
+ * @access private
+ * @since 3.7.0
+ * @param int $expiry
+ */
+function _session_not_expired( $expiry ) {
+        return $expiry >= time();
+}