login/token.php

   1 <?php
   2 // This file is part of Moodle - http://moodle.org/
   3 //
   4 // Moodle is free software: you can redistribute it and/or modify
   5 // it under the terms of the GNU General Public License as published by
   6 // the Free Software Foundation, either version 3 of the License, or
   7 // (at your option) any later version.
   8 //
   9 // Moodle is distributed in the hope that it will be useful,
  10 // but WITHOUT ANY WARRANTY; without even the implied warranty of
  11 // MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  12 // GNU General Public License for more details.
  13 //
  14 // You should have received a copy of the GNU General Public License
  15 // along with Moodle.  If not, see <http://www.gnu.org/licenses/>.
  16
  17 /**
  18  * Return token
  19  * @package    moodlecore
  20  * @copyright  2011 Dongsheng Cai <dongsheng@moodle.com>
  21  * @license    http://www.gnu.org/copyleft/gpl.html GNU GPL v3 or later
  22  */
  23
  24 define('AJAX_SCRIPT', true);
  25 define('REQUIRE_CORRECT_ACCESS', true);
  26 define('NO_MOODLE_COOKIES', true);
  27
  28 require_once(dirname(dirname(__FILE__)) . '/config.php');
  29
  30 $username = required_param('username', PARAM_USERNAME);
  31 $password = required_param('password', PARAM_RAW);
  32 $serviceshortname  = required_param('service',  PARAM_ALPHANUMEXT);
  33
  34 echo $OUTPUT->header();
  35
  36 if (!$CFG->enablewebservices) {
  37     throw new moodle_exception('enablewsdescription', 'webservice');
  38 }
  39 $username = trim(textlib::strtolower($username));
  40 if (is_restored_user($username)) {
  41     throw new moodle_exception('restoredaccountresetpassword', 'webservice');
  42 }
  43 $user = authenticate_user_login($username, $password);
  44 if (!empty($user)) {
  45
  46     //Non admin can not authenticate if maintenance mode
  47     $hassiteconfig = has_capability('moodle/site:config', get_context_instance(CONTEXT_SYSTEM), $user);
  48     if (!empty($CFG->maintenance_enabled) and !$hassiteconfig) {
  49         throw new moodle_exception('sitemaintenance', 'admin');
  50     }
  51
  52     if (isguestuser($user)) {
  53         throw new moodle_exception('noguest');
  54     }
  55     if (empty($user->confirmed)) {
  56         throw new moodle_exception('usernotconfirmed', 'moodle', '', $user->username);
  57     }
  58     // check credential expiry
  59     $userauth = get_auth_plugin($user->auth);
  60     if (!empty($userauth->config->expiration) and $userauth->config->expiration == 1) {
  61         $days2expire = $userauth->password_expire($user->username);
  62         if (intval($days2expire) < 0 ) {
  63             throw new moodle_exception('passwordisexpired', 'webservice');
  64         }
  65     }
  66
  67     // let enrol plugins deal with new enrolments if necessary
  68     enrol_check_plugins($user);
  69
  70     // setup user session to check capability
  71     session_set_user($user);
  72
  73     //check if the service exists and is enabled
  74     $service = $DB->get_record('external_services', array('shortname' => $serviceshortname, 'enabled' => 1));
  75     if (empty($service)) {
  76         // will throw exception if no token found
  77         throw new moodle_exception('servicenotavailable', 'webservice');
  78     }
  79
  80     //check if there is any required system capability
  81     if ($service->requiredcapability and !has_capability($service->requiredcapability, get_context_instance(CONTEXT_SYSTEM), $user)) {
  82         throw new moodle_exception('missingrequiredcapability', 'webservice', '', $service->requiredcapability);
  83     }
  84
  85     //specific checks related to user restricted service
  86     if ($service->restrictedusers) {
  87         $authoriseduser = $DB->get_record('external_services_users',
  88             array('externalserviceid' => $service->id, 'userid' => $user->id));
  89
  90         if (empty($authoriseduser)) {
  91             throw new moodle_exception('usernotallowed', 'webservice', '', $serviceshortname);
  92         }
  93
  94         if (!empty($authoriseduser->validuntil) and $authoriseduser->validuntil < time()) {
  95             throw new moodle_exception('invalidtimedtoken', 'webservice');
  96         }
  97
  98         if (!empty($authoriseduser->iprestriction) and !address_in_subnet(getremoteaddr(), $authoriseduser->iprestriction)) {
  99             throw new moodle_exception('invalidiptoken', 'webservice');
 100         }
 101     }
 102
 103     //Check if a token has already been created for this user and this service
 104     //Note: this could be an admin created or an user created token.
 105     //      It does not really matter we take the first one that is valid.
 106     $tokenssql = "SELECT t.id, t.sid, t.token, t.validuntil, t.iprestriction
 107               FROM {external_tokens} t
 108              WHERE t.userid = ? AND t.externalserviceid = ? AND t.tokentype = ?
 109           ORDER BY t.timecreated ASC";
 110     $tokens = $DB->get_records_sql($tokenssql, array($user->id, $service->id, EXTERNAL_TOKEN_PERMANENT));
 111
 112     //A bit of sanity checks
 113     foreach ($tokens as $key=>$token) {
 114
 115         /// Checks related to a specific token. (script execution continue)
 116         $unsettoken = false;
 117         //if sid is set then there must be a valid associated session no matter the token type
 118         if (!empty($token->sid)) {
 119             $session = session_get_instance();
 120             if (!$session->session_exists($token->sid)){
 121                 //this token will never be valid anymore, delete it
 122                 $DB->delete_records('external_tokens', array('sid'=>$token->sid));
 123                 $unsettoken = true;
 124             }
 125         }
 126
 127         //remove token if no valid anymore
 128         //Also delete this wrong token (similar logic to the web service servers
 129         //    /webservice/lib.php/webservice_server::authenticate_by_token())
 130         if (!empty($token->validuntil) and $token->validuntil < time()) {
 131             $DB->delete_records('external_tokens', array('token'=>$token->token, 'tokentype'=> EXTERNAL_TOKEN_PERMANENT));
 132             $unsettoken = true;
 133         }
 134
 135         // remove token if its ip not in whitelist
 136         if (isset($token->iprestriction) and !address_in_subnet(getremoteaddr(), $token->iprestriction)) {
 137             $unsettoken = true;
 138         }
 139
 140         if ($unsettoken) {
 141             unset($tokens[$key]);
 142         }
 143     }
 144
 145     // if some valid tokens exist then use the most recent
 146     if (count($tokens) > 0) {
 147         $token = array_pop($tokens);
 148     } else {
 149         if ( ($serviceshortname == MOODLE_OFFICIAL_MOBILE_SERVICE and has_capability('moodle/webservice:createmobiletoken', get_system_context()))
 150                 //Note: automatically token generation is not available to admin (they must create a token manually)
 151                 or (!is_siteadmin($user) && has_capability('moodle/webservice:createtoken', get_system_context()))) {
 152             // if service doesn't exist, dml will throw exception
 153             $service_record = $DB->get_record('external_services', array('shortname'=>$serviceshortname, 'enabled'=>1), '*', MUST_EXIST);
 154             // create a new token
 155             $token = new stdClass;
 156             $token->token = md5(uniqid(rand(), 1));
 157             $token->userid = $user->id;
 158             $token->tokentype = EXTERNAL_TOKEN_PERMANENT;
 159             $token->contextid = get_context_instance(CONTEXT_SYSTEM)->id;
 160             $token->creatorid = $user->id;
 161             $token->timecreated = time();
 162             $token->externalserviceid = $service_record->id;
 163             $tokenid = $DB->insert_record('external_tokens', $token);
 164             add_to_log(SITEID, 'webservice', 'automatically create user token', '' , 'User ID: ' . $user->id);
 165             $token->id = $tokenid;
 166         } else {
 167             throw new moodle_exception('cannotcreatetoken', 'webservice', '', $serviceshortname);
 168         }
 169     }
 170
 171     // log token access
 172     $DB->set_field('external_tokens', 'lastaccess', time(), array('id'=>$token->id));
 173
 174     add_to_log(SITEID, 'webservice', 'user request webservice token', '' , 'User ID: ' . $user->id);
 175
 176     $usertoken = new stdClass;
 177     $usertoken->token = $token->token;
 178     echo json_encode($usertoken);
 179 } else {
 180     throw new moodle_exception('usernamenotfound', 'moodle');
 181 }