admin/oauth2callback.php

   1 <?php
   2
   3 // This file is part of Moodle - http://moodle.org/
   4 //
   5 // Moodle is free software: you can redistribute it and/or modify
   6 // it under the terms of the GNU General Public License as published by
   7 // the Free Software Foundation, either version 3 of the License, or
   8 // (at your option) any later version.
   9 //
  10 // Moodle is distributed in the hope that it will be useful,
  11 // but WITHOUT ANY WARRANTY; without even the implied warranty of
  12 // MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  13 // GNU General Public License for more details.
  14 //
  15 // You should have received a copy of the GNU General Public License
  16 // along with Moodle.  If not, see <http://www.gnu.org/licenses/>.
  17
  18 /**
  19  * An oauth2 redirection endpoint which can be used for an application:
  20  * http://tools.ietf.org/html/draft-ietf-oauth-v2-26#section-3.1.2
  21  *
  22  * This is used because some oauth servers will not allow a redirect urls
  23  * with get params (like repository callback) and that needs to be called
  24  * using the state param.
  25  *
  26  * @package    core
  27  * @copyright  2012 Dan Poltawski
  28  * @license    http://www.gnu.org/copyleft/gpl.html GNU GPL v3 or later
  29  */
  30
  31 require_once(__DIR__ . '/../config.php');
  32
  33 // The state parameter we've given (used in moodle as a redirect url).
  34 // Per https://www.rfc-editor.org/rfc/rfc6749#section-4.1.2.1, state is required, even during error responses.
  35 $state = required_param('state', PARAM_LOCALURL);
  36 $redirecturl = new moodle_url($state);
  37 $params = $redirecturl->params();
  38
  39 $error = optional_param('error', '', PARAM_RAW);
  40
  41 if ($error) {
  42     $message = optional_param('error_description', null, PARAM_RAW);
  43
  44     // Errors can occur for authenticated users, such as when a user denies authorization for some internal service call.
  45     // In such cases, propagate the error to the component redirect URI.
  46     if (isloggedin()) {
  47         if (isset($params['sesskey']) && confirm_sesskey($params['sesskey'])) {
  48             $redirecturl->param('error', $error);
  49             if ($message) {
  50                 $redirecturl->param('error_description', $message);
  51             }
  52             redirect($redirecturl);
  53         }
  54     }
  55
  56     // Not logged in or the sesskey verification failed, redirect to login + show errors.
  57     $SESSION->loginerrormsg = $message ?? $error;
  58     redirect(new moodle_url(get_login_url()));
  59 }
  60
  61 // The authorization code generated by the authorization server.
  62 $code = required_param('code', PARAM_RAW);
  63
  64 if (isset($params['sesskey']) and confirm_sesskey($params['sesskey'])) {
  65     $redirecturl->param('oauth2code', $code);
  66     redirect($redirecturl);
  67 } else {
  68     $SESSION->loginerrormsg = get_string('invalidsesskey', 'error');
  69     redirect(new moodle_url(get_login_url()));
  70 }