cms/drupal/modules/openid/openid.module
changeset 541 e756a8c72c3d
equal deleted inserted replaced
540:07239de796bb 541:e756a8c72c3d
       
     1 <?php
       
     2 
       
     3 /**
       
     4  * @file
       
     5  * Implement OpenID Relying Party support for Drupal
       
     6  */
       
     7 
       
     8 /**
       
     9  * Implements hook_menu().
       
    10  */
       
    11 function openid_menu() {
       
    12   $items['openid/authenticate'] = array(
       
    13     'title' => 'OpenID Login',
       
    14     'page callback' => 'openid_authentication_page',
       
    15     'access callback' => 'user_is_anonymous',
       
    16     'type' => MENU_CALLBACK,
       
    17     'file' => 'openid.pages.inc',
       
    18   );
       
    19   $items['user/%user/openid'] = array(
       
    20     'title' => 'OpenID identities',
       
    21     'page callback' => 'openid_user_identities',
       
    22     'page arguments' => array(1),
       
    23     'access callback' => 'user_edit_access',
       
    24     'access arguments' => array(1),
       
    25     'type' => MENU_LOCAL_TASK,
       
    26     'file' => 'openid.pages.inc',
       
    27   );
       
    28   $items['user/%user/openid/delete'] = array(
       
    29     'title' => 'Delete OpenID',
       
    30     'page callback' => 'drupal_get_form',
       
    31     'page arguments' => array('openid_user_delete_form', 1),
       
    32     'access callback' => 'user_edit_access',
       
    33     'access arguments' => array(1),
       
    34     'file' => 'openid.pages.inc',
       
    35   );
       
    36   return $items;
       
    37 }
       
    38 
       
    39 /**
       
    40  * Implements hook_menu_site_status_alter().
       
    41  */
       
    42 function openid_menu_site_status_alter(&$menu_site_status, $path) {
       
    43   // Allow access to openid/authenticate even if site is in offline mode.
       
    44   if ($menu_site_status == MENU_SITE_OFFLINE && user_is_anonymous() && $path == 'openid/authenticate') {
       
    45     $menu_site_status = MENU_SITE_ONLINE;
       
    46   }
       
    47 }
       
    48 
       
    49 /**
       
    50  * Implements hook_admin_paths().
       
    51  */
       
    52 function openid_admin_paths() {
       
    53   $paths = array(
       
    54     'user/*/openid' => TRUE,
       
    55     'user/*/openid/delete' => TRUE,
       
    56   );
       
    57   return $paths;
       
    58 }
       
    59 
       
    60 /**
       
    61  * Implements hook_help().
       
    62  */
       
    63 function openid_help($path, $arg) {
       
    64   switch ($path) {
       
    65     case 'user/%/openid':
       
    66       $output = '<p>' . t('This site supports <a href="@openid-net">OpenID</a>, a secure way to log in to many websites using a single username and password. OpenID can reduce the necessity of managing many usernames and passwords for many websites.', array('@openid-net' => 'http://openid.net')) . '</p>';
       
    67       $output .= '<p>' . t('To use OpenID you must first establish an identity on a public or private OpenID server. If you do not have an OpenID and would like one, look into one of the <a href="@openid-providers">free public providers</a>. You can find out more about OpenID at <a href="@openid-net">this website</a>.', array('@openid-providers' => 'http://openid.net/get/', '@openid-net' => 'http://openid.net')) . '</p>';
       
    68       $output .= '<p>' . t('If you already have an OpenID, enter the URL to your OpenID server below (e.g. myusername.openidprovider.com). Next time you log in, you will be able to use this URL instead of a regular username and password. You can have multiple OpenID servers if you like; just keep adding them here.') . '</p>';
       
    69       return $output;
       
    70     case 'admin/help#openid':
       
    71       $output = '';
       
    72       $output .= '<h3>' . t('About') . '</h3>';
       
    73       $output .= '<p>' . t('The OpenID module allows users to log in using the OpenID single sign on service. <a href="@openid-net">OpenID</a> is a secure method for logging into many websites with a single username and password. It does not require special software, and it does not share passwords with any site to which it is associated, including the site being logged into. The main benefit to users is that they can have a single password that they can use on many websites. This means they can easily update their single password from a centralized location, rather than having to change dozens of passwords individually. For more information, see the online handbook entry for <a href="@handbook">OpenID module</a>.', array('@openid-net' => 'http://openid.net', '@handbook' => 'http://drupal.org/documentation/modules/openid')) . '</p>';
       
    74       $output .= '<h3>' . t('Uses') . '</h3>';
       
    75       $output .= '<dl>';
       
    76       $output .= '<dt>' . t('Logging in with OpenID') . '</dt>';
       
    77       $output .= '<dd>' . t("To log in using OpenID, a user must already have an OpenID account. Users can then create site accounts using their OpenID, assign one or more OpenIDs to an existing account, and log in using an OpenID. This lowers the barrier to registration, which helps increase the user base, and offers convenience and security to the users. Because OpenID cannot guarantee a user is legitimate, email verification is still necessary. When logging in, users are presented with the option of entering their OpenID URL, which will look like <em>myusername.openidprovider.com</em>. The site then communicates with the OpenID server, asking it to verify the identity of the user. If the user is logged into their OpenID server, the server communicates back to your site, verifying the user. If they are not logged in, the OpenID server will ask the user for their password. At no point does the site being logged into record the user's OpenID password.") . '</dd>';
       
    78       $output .= '</dl>';
       
    79       return $output;
       
    80   }
       
    81 }
       
    82 
       
    83 /**
       
    84  * Implements hook_user_insert().
       
    85  */
       
    86 function openid_user_insert(&$edit, $account, $category) {
       
    87   if (!empty($edit['openid_claimed_id'])) {
       
    88     // The user has registered after trying to log in via OpenID.
       
    89     if (variable_get('user_email_verification', TRUE)) {
       
    90       drupal_set_message(t('Once you have verified your e-mail address, you may log in via OpenID.'));
       
    91     }
       
    92     user_set_authmaps($account, array('authname_openid' => $edit['openid_claimed_id']));
       
    93     unset($_SESSION['openid']);
       
    94     unset($edit['openid_claimed_id']);
       
    95   }
       
    96 }
       
    97 
       
    98 /**
       
    99  * Implements hook_user_login().
       
   100  *
       
   101  * Save openid_identifier to visitor cookie.
       
   102  */
       
   103 function openid_user_login(&$edit, $account) {
       
   104   if (isset($_SESSION['openid'])) {
       
   105     // The user has logged in via OpenID.
       
   106     user_cookie_save(array_intersect_key($_SESSION['openid']['user_login_values'], array_flip(array('openid_identifier'))));
       
   107     unset($_SESSION['openid']);
       
   108   }
       
   109 }
       
   110 
       
   111 /**
       
   112  * Implements hook_user_logout().
       
   113  *
       
   114  * Delete any openid_identifier in visitor cookie.
       
   115  */
       
   116 function openid_user_logout($account) {
       
   117   if (isset($_COOKIE['Drupal_visitor_openid_identifier'])) {
       
   118     user_cookie_delete('openid_identifier');
       
   119   }
       
   120 }
       
   121 
       
   122 /**
       
   123  * Implements hook_form_FORM_ID_alter().
       
   124  */
       
   125 function openid_form_user_login_block_alter(&$form, &$form_state) {
       
   126   _openid_user_login_form_alter($form, $form_state);
       
   127 }
       
   128 
       
   129 /**
       
   130  * Implements hook_form_FORM_ID_alter().
       
   131  */
       
   132 function openid_form_user_login_alter(&$form, &$form_state) {
       
   133   _openid_user_login_form_alter($form, $form_state);
       
   134 }
       
   135 
       
   136 function _openid_user_login_form_alter(&$form, &$form_state) {
       
   137   $form['#attached']['css'][] = drupal_get_path('module', 'openid') . '/openid.css';
       
   138   $form['#attached']['js'][] = drupal_get_path('module', 'openid') . '/openid.js';
       
   139   $form['#attached']['library'][] = array('system', 'jquery.cookie');
       
   140   if (!empty($form_state['input']['openid_identifier'])) {
       
   141     $form['name']['#required'] = FALSE;
       
   142     $form['pass']['#required'] = FALSE;
       
   143     unset($form['#submit']);
       
   144     $form['#validate'] = array('openid_login_validate');
       
   145   }
       
   146 
       
   147   $items = array();
       
   148   $items[] = array(
       
   149     'data' => l(t('Log in using OpenID'), '#openid-login', array('external' => TRUE)),
       
   150     'class' => array('openid-link'),
       
   151   );
       
   152   $items[] = array(
       
   153     'data' => l(t('Cancel OpenID login'), '#', array('external' => TRUE)),
       
   154     'class' => array('user-link'),
       
   155   );
       
   156 
       
   157   $form['openid_links'] = array(
       
   158     '#theme' => 'item_list',
       
   159     '#items' => $items,
       
   160     '#attributes' => array('class' => array('openid-links')),
       
   161     '#weight' => 1,
       
   162   );
       
   163 
       
   164   $form['links']['#weight'] = 2;
       
   165 
       
   166   $form['openid_identifier'] = array(
       
   167     '#type' => 'textfield',
       
   168     '#title' => t('Log in using OpenID'),
       
   169     '#size' => $form['name']['#size'],
       
   170     '#maxlength' => 255,
       
   171     '#weight' => -1,
       
   172     '#description' => l(t('What is OpenID?'), 'http://openid.net/', array('external' => TRUE)),
       
   173   );
       
   174   $form['openid.return_to'] = array('#type' => 'hidden', '#value' => url('openid/authenticate', array('absolute' => TRUE, 'query' => user_login_destination())));
       
   175 }
       
   176 
       
   177 /**
       
   178  * Implements hook_form_FORM_ID_alter().
       
   179  *
       
   180  * Prefills the login form with values acquired via OpenID.
       
   181  */
       
   182 function openid_form_user_register_form_alter(&$form, &$form_state) {
       
   183   if (isset($_SESSION['openid']['response'])) {
       
   184     module_load_include('inc', 'openid');
       
   185 
       
   186     $response = $_SESSION['openid']['response'];
       
   187 
       
   188     // Extract Simple Registration keys from the response. We only include
       
   189     // signed keys as required by OpenID Simple Registration Extension 1.0,
       
   190     // section 4.
       
   191     $sreg_values = openid_extract_namespace($response, OPENID_NS_SREG, 'sreg', TRUE);
       
   192     // Extract Attribute Exchanges keys from the response. We only include
       
   193     // signed keys. This is not required by the specification, but it is
       
   194     // recommended by Google, see
       
   195     // http://googlecode.blogspot.com/2011/05/security-advisory-to-websites-using.html
       
   196     $ax_values = openid_extract_namespace($response, OPENID_NS_AX, 'ax', TRUE);
       
   197 
       
   198     if (!empty($sreg_values['nickname'])) {
       
   199       // Use the nickname returned by Simple Registration if available.
       
   200       $form['account']['name']['#default_value'] = $sreg_values['nickname'];
       
   201     }
       
   202     elseif ($ax_name_values = openid_extract_ax_values($ax_values, array('http://axschema.org/namePerson/friendly', 'http://schema.openid.net/namePerson/friendly'))) {
       
   203       // Else, use the first nickname returned by AX if available.
       
   204       $form['account']['name']['#default_value'] = current($ax_name_values);
       
   205     }
       
   206     else {
       
   207       $form['account']['name']['#default_value'] = '';
       
   208     }
       
   209 
       
   210     if (!empty($sreg_values['email'])) {
       
   211       // Use the email returned by Simple Registration if available.
       
   212       $form['account']['mail']['#default_value'] = $sreg_values['email'];
       
   213     }
       
   214     elseif ($ax_mail_values = openid_extract_ax_values($ax_values, array('http://axschema.org/contact/email', 'http://schema.openid.net/contact/email'))) {
       
   215       // Else, use the first nickname returned by AX if available.
       
   216       $form['account']['mail']['#default_value'] = current($ax_mail_values);
       
   217     }
       
   218 
       
   219     // If user_email_verification is off, hide the password field and just fill
       
   220     // with random password to avoid confusion.
       
   221     if (!variable_get('user_email_verification', TRUE)) {
       
   222       $form['account']['pass']['#type'] = 'hidden';
       
   223       $form['account']['pass']['#value'] = user_password();
       
   224     }
       
   225 
       
   226     $form['openid_claimed_id'] = array(
       
   227       '#type' => 'value',
       
   228       '#default_value' => $response['openid.claimed_id'],
       
   229     );
       
   230     $form['openid_display'] = array(
       
   231       '#type' => 'item',
       
   232       '#title' => t('Your OpenID'),
       
   233       '#description' => t('This OpenID will be attached to your account after registration.'),
       
   234       '#markup' => check_plain($response['openid.claimed_id']),
       
   235     );
       
   236   }
       
   237 }
       
   238 
       
   239 /**
       
   240  * Login form _validate hook
       
   241  */
       
   242 function openid_login_validate($form, &$form_state) {
       
   243   $return_to = $form_state['values']['openid.return_to'];
       
   244   if (empty($return_to)) {
       
   245     $return_to = url('', array('absolute' => TRUE));
       
   246   }
       
   247 
       
   248   openid_begin($form_state['values']['openid_identifier'], $return_to, $form_state['values']);
       
   249 }
       
   250 
       
   251 /**
       
   252  * The initial step of OpenID authentication responsible for the following:
       
   253  *  - Perform discovery on the claimed OpenID.
       
   254  *  - If possible, create an association with the Provider's endpoint.
       
   255  *  - Create the authentication request.
       
   256  *  - Perform the appropriate redirect.
       
   257  *
       
   258  * @param $claimed_id The OpenID to authenticate
       
   259  * @param $return_to The endpoint to return to from the OpenID Provider
       
   260  */
       
   261 function openid_begin($claimed_id, $return_to = '', $form_values = array()) {
       
   262   module_load_include('inc', 'openid');
       
   263 
       
   264   $service = NULL;
       
   265   $claimed_id = openid_normalize($claimed_id);
       
   266   $discovery = openid_discovery($claimed_id);
       
   267 
       
   268   if (!empty($discovery['services'])) {
       
   269     $service = _openid_select_service($discovery['services']);
       
   270   }
       
   271 
       
   272   // Quit if the discovery result was empty or if we can't select any service.
       
   273   if (!$discovery || !$service) {
       
   274     form_set_error('openid_identifier', t('Sorry, that is not a valid OpenID. Ensure you have spelled your ID correctly.'));
       
   275     return;
       
   276   }
       
   277 
       
   278   // Set claimed id from discovery.
       
   279   if (!empty($discovery['claimed_id'])) {
       
   280     $claimed_id = $discovery['claimed_id'];
       
   281   }
       
   282 
       
   283   // Store discovered information in the users' session so we don't have to rediscover.
       
   284   $_SESSION['openid']['service'] = $service;
       
   285   // Store the claimed id
       
   286   $_SESSION['openid']['claimed_id'] = $claimed_id;
       
   287   // Store the login form values so we can pass them to
       
   288   // user_exteral_login later.
       
   289   $_SESSION['openid']['user_login_values'] = $form_values;
       
   290 
       
   291   // If a supported math library is present, then create an association.
       
   292   $assoc_handle = '';
       
   293   if (_openid_get_math_library()) {
       
   294     $assoc_handle = openid_association($service['uri']);
       
   295   }
       
   296 
       
   297   if (in_array('http://specs.openid.net/auth/2.0/server', $service['types'])) {
       
   298     // User entered an OP Identifier.
       
   299     $claimed_id = $identity = 'http://specs.openid.net/auth/2.0/identifier_select';
       
   300   }
       
   301   else {
       
   302     // Use Claimed ID and/or OP-Local Identifier from service description, if
       
   303     // available.
       
   304     if (!empty($service['claimed_id'])) {
       
   305       $claimed_id = $service['claimed_id'];
       
   306     }
       
   307     $identity = !empty($service['identity']) ? $service['identity'] : $claimed_id;
       
   308   }
       
   309   $request = openid_authentication_request($claimed_id, $identity, $return_to, $assoc_handle, $service);
       
   310 
       
   311   if ($service['version'] == 2) {
       
   312     openid_redirect($service['uri'], $request);
       
   313   }
       
   314   else {
       
   315     openid_redirect_http($service['uri'], $request);
       
   316   }
       
   317 }
       
   318 
       
   319 /**
       
   320  * Completes OpenID authentication by validating returned data from the OpenID
       
   321  * Provider.
       
   322  *
       
   323  * @param $response Array of returned values from the OpenID Provider.
       
   324  *
       
   325  * @return $response Response values for further processing with
       
   326  *   $response['status'] set to one of 'success', 'failed' or 'cancel'.
       
   327  */
       
   328 function openid_complete($response = array()) {
       
   329   module_load_include('inc', 'openid');
       
   330 
       
   331   if (count($response) == 0) {
       
   332     $response = _openid_response();
       
   333   }
       
   334 
       
   335   // Default to failed response
       
   336   $response['status'] = 'failed';
       
   337   if (isset($_SESSION['openid']['service']['uri']) && isset($_SESSION['openid']['claimed_id'])) {
       
   338     $service = $_SESSION['openid']['service'];
       
   339     $claimed_id = $_SESSION['openid']['claimed_id'];
       
   340     unset($_SESSION['openid']['service']);
       
   341     unset($_SESSION['openid']['claimed_id']);
       
   342     if (isset($response['openid.mode'])) {
       
   343       if ($response['openid.mode'] == 'cancel') {
       
   344         $response['status'] = 'cancel';
       
   345       }
       
   346       else {
       
   347         if (openid_verify_assertion($service, $response)) {
       
   348           // OpenID Authentication, section 7.3.2.3 and Appendix A.5:
       
   349           // The CanonicalID specified in the XRDS document must be used as the
       
   350           // account key. We rely on the XRI proxy resolver to verify that the
       
   351           // provider is authorized to respond on behalf of the specified
       
   352           // identifer (required per Extensible Resource Identifier (XRI)
       
   353           // (XRI) Resolution Version 2.0, section 14.3):
       
   354           if (!empty($service['claimed_id'])) {
       
   355             $response['openid.claimed_id'] = $service['claimed_id'];
       
   356           }
       
   357           elseif ($service['version'] == 2) {
       
   358             // Returned Claimed Identifier could contain unique fragment
       
   359             // identifier to allow identifier recycling so we need to preserve
       
   360             // it in the response.
       
   361             $response_claimed_id = openid_normalize($response['openid.claimed_id']);
       
   362 
       
   363             // OpenID Authentication, section 11.2:
       
   364             // If the returned Claimed Identifier is different from the one sent
       
   365             // to the OpenID Provider, we need to do discovery on the returned
       
   366             // identififer to make sure that the provider is authorized to
       
   367             // respond on behalf of this.
       
   368             if ($response_claimed_id != $claimed_id || $response_claimed_id != $response['openid.identity']) {
       
   369               $discovery = openid_discovery($response['openid.claimed_id']);
       
   370               $uris = array();
       
   371               if ($discovery && !empty($discovery['services'])) {
       
   372                 foreach ($discovery['services'] as $discovered_service) {
       
   373                   if (!in_array('http://specs.openid.net/auth/2.0/server', $discovered_service['types']) && !in_array('http://specs.openid.net/auth/2.0/signon', $discovered_service['types'])) {
       
   374                     continue;
       
   375                   }
       
   376                   // The OP-Local Identifier (if different than the Claimed
       
   377                   // Identifier) must be present in the XRDS document.
       
   378                   if ($response_claimed_id != $response['openid.identity'] && (!isset($discovered_service['identity']) || $discovered_service['identity'] != $response['openid.identity'])) {
       
   379                     continue;
       
   380                   }
       
   381                   $uris[] = $discovered_service['uri'];
       
   382                 }
       
   383               }
       
   384               if (!in_array($service['uri'], $uris)) {
       
   385                 return $response;
       
   386               }
       
   387             }
       
   388           }
       
   389           else {
       
   390             $response['openid.claimed_id'] = $claimed_id;
       
   391           }
       
   392           $response['status'] = 'success';
       
   393         }
       
   394       }
       
   395     }
       
   396   }
       
   397   return $response;
       
   398 }
       
   399 
       
   400 /**
       
   401  * Perform discovery on a claimed ID to determine the OpenID provider endpoint.
       
   402  *
       
   403  * Discovery methods are provided by the hook_openid_discovery_method_info and
       
   404  * could be further altered using the hook_openid_discovery_method_info_alter.
       
   405  *
       
   406  * @param $claimed_id
       
   407  *   The OpenID URL to perform discovery on.
       
   408  *
       
   409  * @return
       
   410  *   The resulting discovery array from the first successful discovery method,
       
   411  *   which must contain following keys:
       
   412  *   - 'services' (required) an array of discovered services (including OpenID
       
   413  *   version, endpoint URI, etc).
       
   414  *   - 'claimed_id' (optional) new claimed identifer, found by following HTTP
       
   415  *   redirects during the services discovery.
       
   416  *   If all the discovery method fails or if no appropriate discovery method is
       
   417  *   found, FALSE is returned.
       
   418  */
       
   419 function openid_discovery($claimed_id) {
       
   420   module_load_include('inc', 'openid');
       
   421 
       
   422   $methods = module_invoke_all('openid_discovery_method_info');
       
   423   drupal_alter('openid_discovery_method_info', $methods);
       
   424 
       
   425   // Execute each method in turn and return first successful discovery.
       
   426   foreach ($methods as $method) {
       
   427     $discovery = $method($claimed_id);
       
   428     if (!empty($discovery)) {
       
   429       return $discovery;
       
   430     }
       
   431   }
       
   432 
       
   433   return FALSE;
       
   434 }
       
   435 
       
   436 /**
       
   437  * Implements hook_openid_discovery_method_info().
       
   438  *
       
   439  * Define standard discovery methods.
       
   440  */
       
   441 function openid_openid_discovery_method_info() {
       
   442   // The discovery process will stop as soon as one discovery method succeed.
       
   443   // We first attempt to discover XRI-based identifiers, then standard XRDS
       
   444   // identifiers via Yadis and HTML-based discovery, conforming to the OpenID 2.0
       
   445   // specification.
       
   446   return array(
       
   447     'xri' => '_openid_xri_discovery',
       
   448     'xrds' => '_openid_xrds_discovery',
       
   449   );
       
   450 }
       
   451 
       
   452 /**
       
   453  * OpenID discovery method: perform an XRI discovery.
       
   454  *
       
   455  * @see http://openid.net/specs/openid-authentication-2_0.html#discovery
       
   456  * @see hook_openid_discovery_method_info()
       
   457  * @see openid_discovery()
       
   458  *
       
   459  * @return
       
   460  *   An array of discovered services and claimed identifier or NULL. See
       
   461  *   openid_discovery() for more specific information.
       
   462  */
       
   463 function _openid_xri_discovery($claimed_id) {
       
   464   if (_openid_is_xri($claimed_id)) {
       
   465     // Resolve XRI using a proxy resolver (Extensible Resource Identifier (XRI)
       
   466     // Resolution Version 2.0, section 11.2 and 14.3).
       
   467     $xrds_url = variable_get('xri_proxy_resolver', 'http://xri.net/') . rawurlencode($claimed_id) . '?_xrd_r=application/xrds+xml';
       
   468     $discovery = _openid_xrds_discovery($xrds_url);
       
   469     if (!empty($discovery['services']) && is_array($discovery['services'])) {
       
   470       foreach ($discovery['services'] as $i => &$service) {
       
   471         $status = $service['xrd']->children(OPENID_NS_XRD)->Status;
       
   472         if ($status && $status->attributes()->cid == 'verified') {
       
   473           $service['claimed_id'] = openid_normalize((string)$service['xrd']->children(OPENID_NS_XRD)->CanonicalID);
       
   474         }
       
   475         else {
       
   476           // Ignore service if the Canonical ID could not be verified.
       
   477           unset($discovery['services'][$i]);
       
   478         }
       
   479       }
       
   480       if (!empty($discovery['services'])) {
       
   481         return $discovery;
       
   482       }
       
   483     }
       
   484   }
       
   485 }
       
   486 
       
   487 /**
       
   488  * OpenID discovery method: perform a XRDS discovery.
       
   489  *
       
   490  * @see http://openid.net/specs/openid-authentication-2_0.html#discovery
       
   491  * @see hook_openid_discovery_method_info()
       
   492  * @see openid_discovery()
       
   493  *
       
   494  * @return
       
   495  *   An array of discovered services and claimed identifier or NULL. See
       
   496  *   openid_discovery() for more specific information.
       
   497  */
       
   498 function _openid_xrds_discovery($claimed_id) {
       
   499   $services = array();
       
   500 
       
   501   $xrds_url = $claimed_id;
       
   502   $scheme = @parse_url($xrds_url, PHP_URL_SCHEME);
       
   503   if ($scheme == 'http' || $scheme == 'https') {
       
   504     // For regular URLs, try Yadis resolution first, then HTML-based discovery
       
   505     $headers = array('Accept' => 'application/xrds+xml');
       
   506     $result = drupal_http_request($xrds_url, array('headers' => $headers));
       
   507 
       
   508     // Check for HTTP error and make sure, that we reach the target. If the
       
   509     // maximum allowed redirects are exhausted, final destination URL isn't
       
   510     // reached, but drupal_http_request() doesn't return any error.
       
   511     // @todo Remove the check for 200 HTTP result code after the following issue
       
   512     // will be fixed: http://drupal.org/node/1096890.
       
   513     if (!isset($result->error) && $result->code == 200) {
       
   514 
       
   515       // Replace the user-entered claimed_id if we received a redirect.
       
   516       if (!empty($result->redirect_url)) {
       
   517         $claimed_id = openid_normalize($result->redirect_url);
       
   518       }
       
   519 
       
   520       if (isset($result->headers['content-type']) && preg_match("/application\/xrds\+xml/", $result->headers['content-type'])) {
       
   521         // Parse XML document to find URL
       
   522         $services = _openid_xrds_parse($result->data);
       
   523       }
       
   524       else {
       
   525         $xrds_url = NULL;
       
   526         if (isset($result->headers['x-xrds-location'])) {
       
   527           $xrds_url = $result->headers['x-xrds-location'];
       
   528         }
       
   529         else {
       
   530           // Look for meta http-equiv link in HTML head
       
   531           $xrds_url = _openid_meta_httpequiv('X-XRDS-Location', $result->data);
       
   532         }
       
   533         if (!empty($xrds_url)) {
       
   534           $headers = array('Accept' => 'application/xrds+xml');
       
   535           $xrds_result = drupal_http_request($xrds_url, array('headers' => $headers));
       
   536           if (!isset($xrds_result->error)) {
       
   537             $services = _openid_xrds_parse($xrds_result->data);
       
   538           }
       
   539         }
       
   540       }
       
   541 
       
   542       // Check for HTML delegation
       
   543       if (count($services) == 0) {
       
   544         // Look for 2.0 links
       
   545         $uri = _openid_link_href('openid2.provider', $result->data);
       
   546         $identity = _openid_link_href('openid2.local_id', $result->data);
       
   547         $type = 'http://specs.openid.net/auth/2.0/signon';
       
   548 
       
   549         // 1.x links
       
   550         if (empty($uri)) {
       
   551           $uri = _openid_link_href('openid.server', $result->data);
       
   552           $identity = _openid_link_href('openid.delegate', $result->data);
       
   553           $type = 'http://openid.net/signon/1.1';
       
   554         }
       
   555         if (!empty($uri)) {
       
   556           $services[] = array(
       
   557             'uri' => $uri,
       
   558             'identity' => $identity,
       
   559             'types' => array($type),
       
   560           );
       
   561         }
       
   562       }
       
   563     }
       
   564   }
       
   565 
       
   566   if (!empty($services)) {
       
   567     return array(
       
   568       'services' => $services,
       
   569       'claimed_id' => $claimed_id,
       
   570     );
       
   571   }
       
   572 }
       
   573 
       
   574 /**
       
   575  * Implements hook_openid_normalization_method_info().
       
   576  *
       
   577  * Define standard normalization methods.
       
   578  */
       
   579 function openid_openid_normalization_method_info() {
       
   580   // OpenID Authentication 2.0, section 7.2:
       
   581   // If the User-supplied Identifier looks like an XRI, treat it as such;
       
   582   // otherwise treat it as an HTTP URL.
       
   583   return array(
       
   584     'xri' => '_openid_xri_normalize',
       
   585     'url' => '_openid_url_normalize',
       
   586   );
       
   587 }
       
   588 
       
   589 /**
       
   590  * Attempt to create a shared secret with the OpenID Provider.
       
   591  *
       
   592  * @param $op_endpoint URL of the OpenID Provider endpoint.
       
   593  *
       
   594  * @return $assoc_handle The association handle.
       
   595  */
       
   596 function openid_association($op_endpoint) {
       
   597   module_load_include('inc', 'openid');
       
   598 
       
   599   // Remove Old Associations:
       
   600   db_delete('openid_association')
       
   601     ->where('created + expires_in < :request_time', array(':request_time' => REQUEST_TIME))
       
   602     ->execute();
       
   603 
       
   604   // Check to see if we have an association for this IdP already
       
   605   $assoc_handle = db_query("SELECT assoc_handle FROM {openid_association} WHERE idp_endpoint_uri = :endpoint", array(':endpoint' => $op_endpoint))->fetchField();
       
   606   if (empty($assoc_handle)) {
       
   607     $mod = OPENID_DH_DEFAULT_MOD;
       
   608     $gen = OPENID_DH_DEFAULT_GEN;
       
   609     $r = _openid_dh_rand($mod);
       
   610     $private = _openid_math_add($r, 1);
       
   611     $public = _openid_math_powmod($gen, $private, $mod);
       
   612 
       
   613     // If there is no existing association, then request one
       
   614     $assoc_request = openid_association_request($public);
       
   615     $assoc_message = _openid_encode_message(_openid_create_message($assoc_request));
       
   616     $assoc_options = array(
       
   617       'headers' => array('Content-Type' => 'application/x-www-form-urlencoded; charset=utf-8'),
       
   618       'method' => 'POST',
       
   619       'data' => $assoc_message,
       
   620     );
       
   621     $assoc_result = drupal_http_request($op_endpoint, $assoc_options);
       
   622     if (isset($assoc_result->error)) {
       
   623       return FALSE;
       
   624     }
       
   625 
       
   626     $assoc_response = _openid_parse_message($assoc_result->data);
       
   627     if (isset($assoc_response['mode']) && $assoc_response['mode'] == 'error') {
       
   628       return FALSE;
       
   629     }
       
   630 
       
   631     if ($assoc_response['session_type'] == 'DH-SHA1') {
       
   632       $spub = _openid_dh_base64_to_long($assoc_response['dh_server_public']);
       
   633       $enc_mac_key = base64_decode($assoc_response['enc_mac_key']);
       
   634       $shared = _openid_math_powmod($spub, $private, $mod);
       
   635       $assoc_response['mac_key'] = base64_encode(_openid_dh_xorsecret($shared, $enc_mac_key));
       
   636     }
       
   637     db_insert('openid_association')
       
   638       ->fields(array(
       
   639         'idp_endpoint_uri' => $op_endpoint,
       
   640         'session_type' => $assoc_response['session_type'],
       
   641         'assoc_handle' => $assoc_response['assoc_handle'],
       
   642         'assoc_type' => $assoc_response['assoc_type'],
       
   643         'expires_in' => $assoc_response['expires_in'],
       
   644         'mac_key' => $assoc_response['mac_key'],
       
   645         'created' => REQUEST_TIME,
       
   646       ))
       
   647       ->execute();
       
   648     $assoc_handle = $assoc_response['assoc_handle'];
       
   649   }
       
   650   return $assoc_handle;
       
   651 }
       
   652 
       
   653 /**
       
   654  * Authenticate a user or attempt registration.
       
   655  *
       
   656  * @param $response Response values from the OpenID Provider.
       
   657  */
       
   658 function openid_authentication($response) {
       
   659   $identity = $response['openid.claimed_id'];
       
   660   $account = user_external_load($identity);
       
   661 
       
   662   // Tries to load user account if user_external_load fails due to possibly
       
   663   // incompletely stored OpenID identifier in the authmap.
       
   664   if (!isset($account->uid) && variable_get('openid_less_obtrusive_transition', FALSE)) {
       
   665     module_load_include('inc', 'openid');
       
   666     $account = _openid_invalid_openid_transition($identity, $response);
       
   667   }
       
   668 
       
   669   if (isset($account->uid)) {
       
   670     if (!variable_get('user_email_verification', TRUE) || $account->login) {
       
   671       // Check if user is blocked.
       
   672       $state['values']['name'] = $account->name;
       
   673       user_login_name_validate(array(), $state);
       
   674       if (!form_get_errors()) {
       
   675         // Load global $user and perform final login tasks.
       
   676         $form_state['uid'] = $account->uid;
       
   677         user_login_submit(array(), $form_state);
       
   678         // Let other modules act on OpenID login
       
   679         module_invoke_all('openid_response', $response, $account);
       
   680       }
       
   681     }
       
   682     else {
       
   683       drupal_set_message(t('You must validate your email address for this account before logging in via OpenID.'));
       
   684     }
       
   685   }
       
   686   elseif (variable_get('user_register', USER_REGISTER_VISITORS_ADMINISTRATIVE_APPROVAL)) {
       
   687     // Register new user.
       
   688 
       
   689     // Save response for use in openid_form_user_register_form_alter().
       
   690     $_SESSION['openid']['response'] = $response;
       
   691 
       
   692     $form_state['values'] = array();
       
   693     $form_state['values']['op'] = t('Create new account');
       
   694     drupal_form_submit('user_register_form', $form_state);
       
   695 
       
   696     if (!empty($form_state['user'])) {
       
   697       module_invoke_all('openid_response', $response, $form_state['user']);
       
   698       drupal_goto();
       
   699     }
       
   700 
       
   701     $messages = drupal_get_messages('error');
       
   702     if (empty($form_state['values']['name']) || empty($form_state['values']['mail'])) {
       
   703       // If the OpenID provider did not provide both a user name and an email
       
   704       // address, ask the user to complete the registration manually instead of
       
   705       // showing the error messages about the missing values generated by FAPI.
       
   706       drupal_set_message(t('Complete the registration by filling out the form below. If you already have an account, you can <a href="@login">log in</a> now and add your OpenID under "My account".', array('@login' => url('user/login'))), 'warning');
       
   707     }
       
   708     else {
       
   709       drupal_set_message(t('Account registration using the information provided by your OpenID provider failed due to the reasons listed below. Complete the registration by filling out the form below. If you already have an account, you can <a href="@login">log in</a> now and add your OpenID under "My account".', array('@login' => url('user/login'))), 'warning');
       
   710       // Append form validation errors below the above warning.
       
   711       foreach ($messages['error'] as $message) {
       
   712         drupal_set_message($message, 'error');
       
   713       }
       
   714     }
       
   715 
       
   716     // We were unable to register a valid new user. Redirect to the normal
       
   717     // registration page and prefill with the values we received.
       
   718     $destination = drupal_get_destination();
       
   719     unset($_GET['destination']);
       
   720     drupal_goto('user/register', array('query' => $destination));
       
   721   }
       
   722   else {
       
   723     drupal_set_message(t('Only site administrators can create new user accounts.'), 'error');
       
   724   }
       
   725   drupal_goto();
       
   726 }
       
   727 
       
   728 function openid_association_request($public) {
       
   729   module_load_include('inc', 'openid');
       
   730 
       
   731   $request = array(
       
   732     'openid.ns' => OPENID_NS_2_0,
       
   733     'openid.mode' => 'associate',
       
   734     'openid.session_type' => 'DH-SHA1',
       
   735     'openid.assoc_type' => 'HMAC-SHA1'
       
   736   );
       
   737 
       
   738   if ($request['openid.session_type'] == 'DH-SHA1' || $request['openid.session_type'] == 'DH-SHA256') {
       
   739     $cpub = _openid_dh_long_to_base64($public);
       
   740     $request['openid.dh_consumer_public'] = $cpub;
       
   741   }
       
   742 
       
   743   return $request;
       
   744 }
       
   745 
       
   746 function openid_authentication_request($claimed_id, $identity, $return_to = '', $assoc_handle = '', $service) {
       
   747   global $base_url;
       
   748 
       
   749   module_load_include('inc', 'openid');
       
   750 
       
   751   $request =  array(
       
   752     'openid.mode' => 'checkid_setup',
       
   753     'openid.identity' => $identity,
       
   754     'openid.assoc_handle' => $assoc_handle,
       
   755     'openid.return_to' => $return_to,
       
   756   );
       
   757 
       
   758   if ($service['version'] == 2) {
       
   759     $request['openid.ns'] = OPENID_NS_2_0;
       
   760     $request['openid.claimed_id'] = $claimed_id;
       
   761     $request['openid.realm'] = $base_url .'/';
       
   762   }
       
   763   else {
       
   764     $request['openid.trust_root'] = $base_url .'/';
       
   765   }
       
   766 
       
   767   // Always request Simple Registration. The specification doesn't mandate
       
   768   // that the Endpoint advertise OPENID_NS_SREG in the service description.
       
   769   $request['openid.ns.sreg'] = OPENID_NS_SREG;
       
   770   $request['openid.sreg.required'] = 'nickname,email';
       
   771 
       
   772   // Request Attribute Exchange, if available.
       
   773   // We only request the minimum attributes we need here, contributed modules
       
   774   // can alter the request to add more attribute, and map them to profile fields.
       
   775   if (in_array(OPENID_NS_AX, $service['types'])) {
       
   776     $request['openid.ns.ax'] = OPENID_NS_AX;
       
   777     $request['openid.ax.mode'] = 'fetch_request';
       
   778     $request['openid.ax.required'] = 'mail_ao,name_ao,mail_son,name_son';
       
   779 
       
   780     // Implementors disagree on which URIs to use, even for simple
       
   781     // attributes like name and email (*sigh*). We ask for both axschema.org
       
   782     // attributes (which are supposed to be newer), and schema.openid.net ones
       
   783     // (which are supposed to be legacy).
       
   784 
       
   785     // Attributes as defined by axschema.org.
       
   786     $request['openid.ax.type.mail_ao'] = 'http://axschema.org/contact/email';
       
   787     $request['openid.ax.type.name_ao'] = 'http://axschema.org/namePerson/friendly';
       
   788 
       
   789     // Attributes as defined by schema.openid.net.
       
   790     $request['openid.ax.type.mail_son'] = 'http://schema.openid.net/contact/email';
       
   791     $request['openid.ax.type.name_son'] = 'http://schema.openid.net/namePerson/friendly';
       
   792   }
       
   793 
       
   794   $request = array_merge($request, module_invoke_all('openid', 'request', $request));
       
   795 
       
   796   // module_invoke_all() uses array_merge_recursive() which might return nested
       
   797   // arrays if two or more modules alter a given parameter, resulting in an
       
   798   // invalid request format. To ensure this doesn't happen, we flatten the returned
       
   799   // value by taking the last entry in the array if an array is returned.
       
   800   $flattened_request = array();
       
   801   foreach ($request as $key => $value) {
       
   802     if (is_array($value)) {
       
   803       $flattened_request[$key] = end($value);
       
   804     }
       
   805     else {
       
   806       $flattened_request[$key] = $value;
       
   807     }
       
   808   }
       
   809 
       
   810   return $flattened_request;
       
   811 }
       
   812 
       
   813 /**
       
   814  * Attempt to verify the response received from the OpenID Provider.
       
   815  *
       
   816  * @param $service
       
   817  *   Array describing the OpenID provider.
       
   818  * @param $response
       
   819  *   Array of response values from the provider.
       
   820  *
       
   821  * @return boolean
       
   822  * @see http://openid.net/specs/openid-authentication-2_0.html#rfc.section.11.4
       
   823  */
       
   824 function openid_verify_assertion($service, $response) {
       
   825   module_load_include('inc', 'openid');
       
   826 
       
   827   // http://openid.net/specs/openid-authentication-2_0.html#rfc.section.11.3
       
   828   // Check the Nonce to protect against replay attacks.
       
   829   if (!openid_verify_assertion_nonce($service, $response)) {
       
   830     return FALSE;
       
   831   }
       
   832 
       
   833   // http://openid.net/specs/openid-authentication-2_0.html#rfc.section.11.1
       
   834   // Verifying the return URL.
       
   835   if (!openid_verify_assertion_return_url($service, $response)) {
       
   836     return FALSE;
       
   837   }
       
   838 
       
   839   // http://openid.net/specs/openid-authentication-2_0.html#rfc.section.11.4
       
   840   // Verify the signatures.
       
   841   $valid = FALSE;
       
   842   $association = FALSE;
       
   843 
       
   844   // If the OP returned a openid.invalidate_handle, we have to proceed with
       
   845   // direct verification: ignore the openid.assoc_handle, even if present.
       
   846   // See http://openid.net/specs/openid-authentication-2_0.html#rfc.section.11.4.1
       
   847   if (!empty($response['openid.assoc_handle']) && empty($response['openid.invalidate_handle'])) {
       
   848     $association = db_query("SELECT * FROM {openid_association} WHERE idp_endpoint_uri = :endpoint AND assoc_handle = :assoc_handle", array(':endpoint' => $service['uri'], ':assoc_handle' => $response['openid.assoc_handle']))->fetchObject();
       
   849   }
       
   850 
       
   851   if ($association && isset($association->session_type)) {
       
   852     // http://openid.net/specs/openid-authentication-2_0.html#rfc.section.11.4.2
       
   853     // Verification using an association.
       
   854     $valid = openid_verify_assertion_signature($service, $association, $response);
       
   855   }
       
   856   else {
       
   857     // http://openid.net/specs/openid-authentication-2_0.html#rfc.section.11.4.2
       
   858     // Direct verification.
       
   859     // The verification requests contain all the fields from the response,
       
   860     // except openid.mode.
       
   861     $request = $response;
       
   862     $request['openid.mode'] = 'check_authentication';
       
   863     $message = _openid_create_message($request);
       
   864     $options = array(
       
   865       'headers' => array('Content-Type' => 'application/x-www-form-urlencoded; charset=utf-8'),
       
   866       'method' => 'POST',
       
   867       'data' => _openid_encode_message($message),
       
   868     );
       
   869     $result = drupal_http_request($service['uri'], $options);
       
   870     if (!isset($result->error)) {
       
   871       $response = _openid_parse_message($result->data);
       
   872 
       
   873       if (strtolower(trim($response['is_valid'])) == 'true') {
       
   874         $valid = TRUE;
       
   875         if (!empty($response['invalidate_handle'])) {
       
   876           // This association handle has expired on the OP side, remove it from the
       
   877           // database to avoid reusing it again on a subsequent authentication request.
       
   878           // See http://openid.net/specs/openid-authentication-2_0.html#rfc.section.11.4.2.2
       
   879           db_delete('openid_association')
       
   880             ->condition('idp_endpoint_uri', $service['uri'])
       
   881             ->condition('assoc_handle', $response['invalidate_handle'])
       
   882             ->execute();
       
   883         }
       
   884       }
       
   885       else {
       
   886         $valid = FALSE;
       
   887       }
       
   888     }
       
   889   }
       
   890   return $valid;
       
   891 }
       
   892 
       
   893 
       
   894 /**
       
   895  * Verify the signature of the response received from the OpenID provider.
       
   896  *
       
   897  * @param $service
       
   898  *   Array describing the OpenID provider.
       
   899  * @param $association
       
   900  *   Information on the association with the OpenID provider.
       
   901  * @param $response
       
   902  *   Array of response values from the provider.
       
   903  *
       
   904  * @return
       
   905  *   TRUE if the signature is valid and covers all fields required to be signed.
       
   906  * @see http://openid.net/specs/openid-authentication-2_0.html#rfc.section.11.4
       
   907  */
       
   908 function openid_verify_assertion_signature($service, $association, $response) {
       
   909   if ($service['version'] == 2) {
       
   910     // OpenID Authentication 2.0, section 10.1:
       
   911     // These keys must always be signed.
       
   912     $mandatory_keys = array('op_endpoint', 'return_to', 'response_nonce', 'assoc_handle');
       
   913     if (isset($response['openid.claimed_id'])) {
       
   914       // If present, these two keys must also be signed. According to the spec,
       
   915       // they are either both present or both absent.
       
   916       $mandatory_keys[] = 'claimed_id';
       
   917       $mandatory_keys[] = 'identity';
       
   918     }
       
   919   }
       
   920   else {
       
   921     // OpenID Authentication 1.1. section 4.3.3.
       
   922     $mandatory_keys = array('identity', 'return_to');
       
   923   }
       
   924 
       
   925   $keys_to_sign = explode(',', $response['openid.signed']);
       
   926 
       
   927   if (count(array_diff($mandatory_keys, $keys_to_sign)) > 0) {
       
   928     return FALSE;
       
   929   }
       
   930 
       
   931   return _openid_signature($association, $response, $keys_to_sign) === $response['openid.sig'];
       
   932 }
       
   933 
       
   934 /**
       
   935  * Verify that the nonce has not been used in earlier assertions from the same OpenID provider.
       
   936  *
       
   937  * @param $service
       
   938  *   Array describing the OpenID provider.
       
   939  * @param $response
       
   940  *   Array of response values from the provider.
       
   941  *
       
   942  * @return
       
   943  *   TRUE if the nonce has not expired and has not been used earlier.
       
   944  */
       
   945 function openid_verify_assertion_nonce($service, $response) {
       
   946   if ($service['version'] != 2) {
       
   947     return TRUE;
       
   948   }
       
   949 
       
   950   if (preg_match('/^(\d{4})-(\d{2})-(\d{2})T(\d{2}):(\d{2}):(\d{2})Z/', $response['openid.response_nonce'], $matches)) {
       
   951     list(, $year, $month, $day, $hour, $minutes, $seconds) = $matches;
       
   952     $nonce_timestamp = gmmktime($hour, $minutes, $seconds, $month, $day, $year);
       
   953   }
       
   954   else {
       
   955     watchdog('openid', 'Nonce from @endpoint rejected because it is not correctly formatted, nonce: @nonce.', array('@endpoint' => $service['uri'], '@nonce' => $response['openid.response_nonce']), WATCHDOG_WARNING);
       
   956     return FALSE;
       
   957   }
       
   958 
       
   959   // A nonce with a timestamp to far in the past or future will already have
       
   960   // been removed and cannot be checked for single use anymore.
       
   961   $time = time();
       
   962   $expiry = 900;
       
   963   if ($nonce_timestamp <= $time - $expiry || $nonce_timestamp >= $time + $expiry) {
       
   964     watchdog('openid', 'Nonce received from @endpoint is out of range (time difference: @intervals). Check possible clock skew.', array('@endpoint' => $service['uri'], '@interval' => $time - $nonce_timestamp), WATCHDOG_WARNING);
       
   965     return FALSE;
       
   966   }
       
   967 
       
   968   // Record that this nonce was used.
       
   969   db_insert('openid_nonce')
       
   970     ->fields(array(
       
   971       'idp_endpoint_uri' => $service['uri'],
       
   972       'nonce' => $response['openid.response_nonce'],
       
   973       'expires' => $nonce_timestamp + $expiry,
       
   974     ))
       
   975     ->execute();
       
   976 
       
   977   // Count the number of times this nonce was used.
       
   978   $count_used = db_query("SELECT COUNT(*) FROM {openid_nonce} WHERE nonce = :nonce AND idp_endpoint_uri = :idp_endpoint_uri", array(
       
   979     ':nonce' => $response['openid.response_nonce'],
       
   980     ':idp_endpoint_uri' => $service['uri'],
       
   981   ))->fetchField();
       
   982 
       
   983   if ($count_used == 1) {
       
   984     return TRUE;
       
   985   }
       
   986   else {
       
   987     watchdog('openid', 'Nonce replay attempt blocked from @ip, nonce: @nonce.', array('@ip' => ip_address(), '@nonce' => $response['openid.response_nonce']), WATCHDOG_CRITICAL);
       
   988     return FALSE;
       
   989   }
       
   990 }
       
   991 
       
   992 
       
   993 /**
       
   994  * Verify that openid.return_to matches the current URL.
       
   995  *
       
   996  * See OpenID  Authentication 2.0, section 11.1. While OpenID Authentication
       
   997  * 1.1, section 4.3 does not mandate return_to verification, the received
       
   998  * return_to should still match these constraints.
       
   999  *
       
  1000  * @param $service
       
  1001  *   Array describing the OpenID provider.
       
  1002  * @param $response
       
  1003  *   Array of response values from the provider.
       
  1004  *
       
  1005  * @return
       
  1006  *   TRUE if return_to is valid, FALSE otherwise.
       
  1007  */
       
  1008 function openid_verify_assertion_return_url($service, $response) {
       
  1009   global $base_url;
       
  1010 
       
  1011   $return_to_parts = parse_url($response['openid.return_to']);
       
  1012 
       
  1013   $base_url_parts = parse_url($base_url);
       
  1014   $current_parts = parse_url($base_url_parts['scheme'] .'://'. $base_url_parts['host'] . request_uri());
       
  1015 
       
  1016   if ($return_to_parts['scheme'] != $current_parts['scheme'] || $return_to_parts['host'] != $current_parts['host'] || $return_to_parts['path'] != $current_parts['path']) {
       
  1017     return FALSE;
       
  1018   }
       
  1019   // Verify that all query parameters in the openid.return_to URL have
       
  1020   // the same value in the current URL. In addition, the current URL
       
  1021   // contains a number of other parameters added by the OpenID Provider.
       
  1022   parse_str(isset($return_to_parts['query']) ? $return_to_parts['query'] : '', $return_to_query_parameters);
       
  1023   foreach ($return_to_query_parameters as $name => $value) {
       
  1024     if (!isset($_GET[$name]) || $_GET[$name] != $value) {
       
  1025       return FALSE;
       
  1026     }
       
  1027   }
       
  1028   return TRUE;
       
  1029 }
       
  1030 
       
  1031 /**
       
  1032  * Remove expired nonces from the database.
       
  1033  *
       
  1034  * Implements hook_cron().
       
  1035  */
       
  1036 function openid_cron() {
       
  1037   db_delete('openid_nonce')
       
  1038     ->condition('expires', REQUEST_TIME, '<')
       
  1039     ->execute();
       
  1040 }