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See Release Notes

  • Bug fixes for general core bugs in 3.11.x will end 14 Nov 2022 (12 months plus 6 months extension).
  • Bug fixes for security issues in 3.11.x will end 13 Nov 2023 (18 months plus 12 months extension).
  • PHP version: minimum PHP 7.3.0 Note: minimum PHP version has increased since Moodle 3.10. PHP 7.4.x is supported too.
/lib/ -> authlib.php (source)

Differences Between: [Versions 310 and 311] [Versions 311 and 401] [Versions 311 and 402] [Versions 311 and 403] [Versions 39 and 311]

   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   * Multiple plugin authentication Support library
  20   *
  21   * 2006-08-28  File created, AUTH return values defined.
  22   *
  23   * @package    core
  24   * @subpackage auth
  25   * @copyright  1999 onwards Martin Dougiamas  http://dougiamas.com
  26   * @license    http://www.gnu.org/copyleft/gpl.html GNU GPL v3 or later
  27   */
  28  
  29  defined('MOODLE_INTERNAL') || die();
  30  
  31  /**
  32   * Returned when the login was successful.
  33   */
  34  define('AUTH_OK',     0);
  35  
  36  /**
  37   * Returned when the login was unsuccessful.
  38   */
  39  define('AUTH_FAIL',   1);
  40  
  41  /**
  42   * Returned when the login was denied (a reason for AUTH_FAIL).
  43   */
  44  define('AUTH_DENIED', 2);
  45  
  46  /**
  47   * Returned when some error occurred (a reason for AUTH_FAIL).
  48   */
  49  define('AUTH_ERROR',  4);
  50  
  51  /**
  52   * Authentication - error codes for user confirm
  53   */
  54  define('AUTH_CONFIRM_FAIL', 0);
  55  define('AUTH_CONFIRM_OK', 1);
  56  define('AUTH_CONFIRM_ALREADY', 2);
  57  define('AUTH_CONFIRM_ERROR', 3);
  58  
  59  # MDL-14055
  60  define('AUTH_REMOVEUSER_KEEP', 0);
  61  define('AUTH_REMOVEUSER_SUSPEND', 1);
  62  define('AUTH_REMOVEUSER_FULLDELETE', 2);
  63  
  64  /** Login attempt successful. */
  65  define('AUTH_LOGIN_OK', 0);
  66  
  67  /** Can not login because user does not exist. */
  68  define('AUTH_LOGIN_NOUSER', 1);
  69  
  70  /** Can not login because user is suspended. */
  71  define('AUTH_LOGIN_SUSPENDED', 2);
  72  
  73  /** Can not login, most probably password did not match. */
  74  define('AUTH_LOGIN_FAILED', 3);
  75  
  76  /** Can not login because user is locked out. */
  77  define('AUTH_LOGIN_LOCKOUT', 4);
  78  
  79  /** Can not login becauser user is not authorised. */
  80  define('AUTH_LOGIN_UNAUTHORISED', 5);
  81  
  82  /**
  83   * Abstract authentication plugin.
  84   *
  85   * @license http://www.gnu.org/copyleft/gpl.html GNU GPL v3 or later
  86   * @package moodlecore
  87   */
  88  class auth_plugin_base {
  89  
  90      /**
  91       * The configuration details for the plugin.
  92       * @var object
  93       */
  94      var $config;
  95  
  96      /**
  97       * Authentication plugin type - the same as db field.
  98       * @var string
  99       */
 100      var $authtype;
 101      /*
 102       * The fields we can lock and update from/to external authentication backends
 103       * @var array
 104       */
 105      var $userfields = \core_user::AUTHSYNCFIELDS;
 106  
 107      /**
 108       * Moodle custom fields to sync with.
 109       * @var array()
 110       */
 111      var $customfields = null;
 112  
 113      /**
 114       * The tag we want to prepend to any error log messages.
 115       *
 116       * @var string
 117       */
 118      protected $errorlogtag = '';
 119  
 120      /**
 121       * This is the primary method that is used by the authenticate_user_login()
 122       * function in moodlelib.php.
 123       *
 124       * This method should return a boolean indicating
 125       * whether or not the username and password authenticate successfully.
 126       *
 127       * Returns true if the username and password work and false if they are
 128       * wrong or don't exist.
 129       *
 130       * @param string $username The username (with system magic quotes)
 131       * @param string $password The password (with system magic quotes)
 132       *
 133       * @return bool Authentication success or failure.
 134       */
 135      function user_login($username, $password) {
 136          print_error('mustbeoveride', 'debug', '', 'user_login()' );
 137      }
 138  
 139      /**
 140       * Returns true if this authentication plugin can change the users'
 141       * password.
 142       *
 143       * @return bool
 144       */
 145      function can_change_password() {
 146          //override if needed
 147          return false;
 148      }
 149  
 150      /**
 151       * Returns the URL for changing the users' passwords, or empty if the default
 152       * URL can be used.
 153       *
 154       * This method is used if can_change_password() returns true.
 155       * This method is called only when user is logged in, it may use global $USER.
 156       * If you are using a plugin config variable in this method, please make sure it is set before using it,
 157       * as this method can be called even if the plugin is disabled, in which case the config values won't be set.
 158       *
 159       * @return moodle_url url of the profile page or null if standard used
 160       */
 161      function change_password_url() {
 162          //override if needed
 163          return null;
 164      }
 165  
 166      /**
 167       * Returns true if this authentication plugin can edit the users'
 168       * profile.
 169       *
 170       * @return bool
 171       */
 172      function can_edit_profile() {
 173          //override if needed
 174          return true;
 175      }
 176  
 177      /**
 178       * Returns the URL for editing the users' profile, or empty if the default
 179       * URL can be used.
 180       *
 181       * This method is used if can_edit_profile() returns true.
 182       * This method is called only when user is logged in, it may use global $USER.
 183       *
 184       * @return moodle_url url of the profile page or null if standard used
 185       */
 186      function edit_profile_url() {
 187          //override if needed
 188          return null;
 189      }
 190  
 191      /**
 192       * Returns true if this authentication plugin is "internal".
 193       *
 194       * Internal plugins use password hashes from Moodle user table for authentication.
 195       *
 196       * @return bool
 197       */
 198      function is_internal() {
 199          //override if needed
 200          return true;
 201      }
 202  
 203      /**
 204       * Returns false if this plugin is enabled but not configured.
 205       *
 206       * @return bool
 207       */
 208      public function is_configured() {
 209          return false;
 210      }
 211  
 212      /**
 213       * Indicates if password hashes should be stored in local moodle database.
 214       * @return bool true means md5 password hash stored in user table, false means flag 'not_cached' stored there instead
 215       */
 216      function prevent_local_passwords() {
 217          return !$this->is_internal();
 218      }
 219  
 220      /**
 221       * Indicates if moodle should automatically update internal user
 222       * records with data from external sources using the information
 223       * from get_userinfo() method.
 224       *
 225       * @return bool true means automatically copy data from ext to user table
 226       */
 227      function is_synchronised_with_external() {
 228          return !$this->is_internal();
 229      }
 230  
 231      /**
 232       * Updates the user's password.
 233       *
 234       * In previous versions of Moodle, the function
 235       * auth_user_update_password accepted a username as the first parameter. The
 236       * revised function expects a user object.
 237       *
 238       * @param  object  $user        User table object
 239       * @param  string  $newpassword Plaintext password
 240       *
 241       * @return bool                  True on success
 242       */
 243      function user_update_password($user, $newpassword) {
 244          //override if needed
 245          return true;
 246      }
 247  
 248      /**
 249       * Called when the user record is updated.
 250       * Modifies user in external database. It takes olduser (before changes) and newuser (after changes)
 251       * compares information saved modified information to external db.
 252       *
 253       * @param mixed $olduser     Userobject before modifications    (without system magic quotes)
 254       * @param mixed $newuser     Userobject new modified userobject (without system magic quotes)
 255       * @return boolean true if updated or update ignored; false if error
 256       *
 257       */
 258      function user_update($olduser, $newuser) {
 259          //override if needed
 260          return true;
 261      }
 262  
 263      /**
 264       * User delete requested - internal user record is mared as deleted already, username not present anymore.
 265       *
 266       * Do any action in external database.
 267       *
 268       * @param object $user       Userobject before delete    (without system magic quotes)
 269       * @return void
 270       */
 271      function user_delete($olduser) {
 272          //override if needed
 273          return;
 274      }
 275  
 276      /**
 277       * Returns true if plugin allows resetting of internal password.
 278       *
 279       * @return bool
 280       */
 281      function can_reset_password() {
 282          //override if needed
 283          return false;
 284      }
 285  
 286      /**
 287       * Returns true if plugin allows resetting of internal password.
 288       *
 289       * @return bool
 290       */
 291      function can_signup() {
 292          //override if needed
 293          return false;
 294      }
 295  
 296      /**
 297       * Sign up a new user ready for confirmation.
 298       * Password is passed in plaintext.
 299       *
 300       * @param object $user new user object
 301       * @param boolean $notify print notice with link and terminate
 302       */
 303      function user_signup($user, $notify=true) {
 304          //override when can signup
 305          print_error('mustbeoveride', 'debug', '', 'user_signup()' );
 306      }
 307  
 308      /**
 309       * Return a form to capture user details for account creation.
 310       * This is used in /login/signup.php.
 311       * @return moodle_form A form which edits a record from the user table.
 312       */
 313      function signup_form() {
 314          global $CFG;
 315  
 316          require_once($CFG->dirroot.'/login/signup_form.php');
 317          return new login_signup_form(null, null, 'post', '', array('autocomplete'=>'on'));
 318      }
 319  
 320      /**
 321       * Returns true if plugin allows confirming of new users.
 322       *
 323       * @return bool
 324       */
 325      function can_confirm() {
 326          //override if needed
 327          return false;
 328      }
 329  
 330      /**
 331       * Confirm the new user as registered.
 332       *
 333       * @param string $username
 334       * @param string $confirmsecret
 335       */
 336      function user_confirm($username, $confirmsecret) {
 337          //override when can confirm
 338          print_error('mustbeoveride', 'debug', '', 'user_confirm()' );
 339      }
 340  
 341      /**
 342       * Checks if user exists in external db
 343       *
 344       * @param string $username (with system magic quotes)
 345       * @return bool
 346       */
 347      function user_exists($username) {
 348          //override if needed
 349          return false;
 350      }
 351  
 352      /**
 353       * return number of days to user password expires
 354       *
 355       * If userpassword does not expire it should return 0. If password is already expired
 356       * it should return negative value.
 357       *
 358       * @param mixed $username username (with system magic quotes)
 359       * @return integer
 360       */
 361      function password_expire($username) {
 362          return 0;
 363      }
 364      /**
 365       * Sync roles for this user - usually creator
 366       *
 367       * @param $user object user object (without system magic quotes)
 368       */
 369      function sync_roles($user) {
 370          //override if needed
 371      }
 372  
 373      /**
 374       * Read user information from external database and returns it as array().
 375       * Function should return all information available. If you are saving
 376       * this information to moodle user-table you should honour synchronisation flags
 377       *
 378       * @param string $username username
 379       *
 380       * @return mixed array with no magic quotes or false on error
 381       */
 382      function get_userinfo($username) {
 383          //override if needed
 384          return array();
 385      }
 386  
 387      /**
 388       * Prints a form for configuring this authentication plugin.
 389       *
 390       * This function is called from admin/auth.php, and outputs a full page with
 391       * a form for configuring this plugin.
 392       *
 393       * @param object $config
 394       * @param object $err
 395       * @param array $user_fields
 396       * @deprecated since Moodle 3.3
 397       */
 398      function config_form($config, $err, $user_fields) {
 399          debugging('Use of config.html files have been deprecated, please update your code to use the admin settings API.');
 400          //override if needed
 401      }
 402  
 403      /**
 404       * A chance to validate form data, and last chance to
 405       * do stuff before it is inserted in config_plugin
 406       * @param object object with submitted configuration settings (without system magic quotes)
 407       * @param array $err array of error messages
 408       * @deprecated since Moodle 3.3
 409       */
 410       function validate_form($form, &$err) {
 411          debugging('Use of config.html files have been deprecated, please update your code to use the admin settings API.');
 412          //override if needed
 413      }
 414  
 415      /**
 416       * Processes and stores configuration data for this authentication plugin.
 417       *
 418       * @param object object with submitted configuration settings (without system magic quotes)
 419       * @deprecated since Moodle 3.3
 420       */
 421      function process_config($config) {
 422          debugging('Use of config.html files have been deprecated, please update your code to use the admin settings API.');
 423          //override if needed
 424          return true;
 425      }
 426  
 427      /**
 428       * Hook for overriding behaviour of login page.
 429       * This method is called from login/index.php page for all enabled auth plugins.
 430       *
 431       * @global object
 432       * @global object
 433       */
 434      function loginpage_hook() {
 435          global $frm;  // can be used to override submitted login form
 436          global $user; // can be used to replace authenticate_user_login()
 437  
 438          //override if needed
 439      }
 440  
 441      /**
 442       * Hook for overriding behaviour before going to the login page.
 443       *
 444       * This method is called from require_login from potentially any page for
 445       * all enabled auth plugins and gives each plugin a chance to redirect
 446       * directly to an external login page, or to instantly login a user where
 447       * possible.
 448       *
 449       * If an auth plugin implements this hook, it must not rely on ONLY this
 450       * hook in order to work, as there are many ways a user can browse directly
 451       * to the standard login page. As a general rule in this case you should
 452       * also implement the loginpage_hook as well.
 453       *
 454       */
 455      function pre_loginpage_hook() {
 456          // override if needed, eg by redirecting to an external login page
 457          // or logging in a user:
 458          // complete_user_login($user);
 459      }
 460  
 461      /**
 462       * Pre user_login hook.
 463       * This method is called from authenticate_user_login() right after the user
 464       * object is generated. This gives the auth plugins an option to make adjustments
 465       * before the verification process starts.
 466       *
 467       * @param object $user user object, later used for $USER
 468       */
 469      public function pre_user_login_hook(&$user) {
 470          // Override if needed.
 471      }
 472  
 473      /**
 474       * Post authentication hook.
 475       * This method is called from authenticate_user_login() for all enabled auth plugins.
 476       *
 477       * @param object $user user object, later used for $USER
 478       * @param string $username (with system magic quotes)
 479       * @param string $password plain text password (with system magic quotes)
 480       */
 481      function user_authenticated_hook(&$user, $username, $password) {
 482          //override if needed
 483      }
 484  
 485      /**
 486       * Pre logout hook.
 487       * This method is called from require_logout() for all enabled auth plugins,
 488       *
 489       * @global object
 490       */
 491      function prelogout_hook() {
 492          global $USER; // use $USER->auth to find the plugin used for login
 493  
 494          //override if needed
 495      }
 496  
 497      /**
 498       * Hook for overriding behaviour of logout page.
 499       * This method is called from login/logout.php page for all enabled auth plugins.
 500       *
 501       * @global object
 502       * @global string
 503       */
 504      function logoutpage_hook() {
 505          global $USER;     // use $USER->auth to find the plugin used for login
 506          global $redirect; // can be used to override redirect after logout
 507  
 508          //override if needed
 509      }
 510  
 511      /**
 512       * Hook called before timing out of database session.
 513       * This is useful for SSO and MNET.
 514       *
 515       * @param object $user
 516       * @param string $sid session id
 517       * @param int $timecreated start of session
 518       * @param int $timemodified user last seen
 519       * @return bool true means do not timeout session yet
 520       */
 521      function ignore_timeout_hook($user, $sid, $timecreated, $timemodified) {
 522          return false;
 523      }
 524  
 525      /**
 526       * Return the properly translated human-friendly title of this auth plugin
 527       *
 528       * @todo Document this function
 529       */
 530      function get_title() {
 531          return get_string('pluginname', "auth_{$this->authtype}");
 532      }
 533  
 534      /**
 535       * Get the auth description (from core or own auth lang files)
 536       *
 537       * @return string The description
 538       */
 539      function get_description() {
 540          $authdescription = get_string("auth_{$this->authtype}description", "auth_{$this->authtype}");
 541          return $authdescription;
 542      }
 543  
 544      /**
 545       * Returns whether or not the captcha element is enabled.
 546       *
 547       * @abstract Implement in child classes
 548       * @return bool
 549       */
 550      function is_captcha_enabled() {
 551          return false;
 552      }
 553  
 554      /**
 555       * Returns whether or not this authentication plugin can be manually set
 556       * for users, for example, when bulk uploading users.
 557       *
 558       * This should be overriden by authentication plugins where setting the
 559       * authentication method manually is allowed.
 560       *
 561       * @return bool
 562       * @since Moodle 2.6
 563       */
 564      function can_be_manually_set() {
 565          // Override if needed.
 566          return false;
 567      }
 568  
 569      /**
 570       * Returns a list of potential IdPs that this authentication plugin supports.
 571       *
 572       * This is used to provide links on the login page and the login block.
 573       *
 574       * The parameter $wantsurl is typically used by the plugin to implement a
 575       * return-url feature.
 576       *
 577       * The returned value is expected to be a list of associative arrays with
 578       * string keys:
 579       *
 580       * - url => (moodle_url|string) URL of the page to send the user to for authentication
 581       * - name => (string) Human readable name of the IdP
 582       * - iconurl => (moodle_url|string) URL of the icon representing the IdP (since Moodle 3.3)
 583       *
 584       * For legacy reasons, pre-3.3 plugins can provide the icon via the key:
 585       *
 586       * - icon => (pix_icon) Icon representing the IdP
 587       *
 588       * @param string $wantsurl The relative url fragment the user wants to get to.
 589       * @return array List of associative arrays with keys url, name, iconurl|icon
 590       */
 591      function loginpage_idp_list($wantsurl) {
 592          return array();
 593      }
 594  
 595      /**
 596       * Return custom user profile fields.
 597       *
 598       * @return array list of custom fields.
 599       */
 600      public function get_custom_user_profile_fields() {
 601          global $CFG;
 602          require_once($CFG->dirroot . '/user/profile/lib.php');
 603  
 604          // If already retrieved then return.
 605          if (!is_null($this->customfields)) {
 606              return $this->customfields;
 607          }
 608  
 609          $this->customfields = array();
 610          if ($proffields = profile_get_custom_fields()) {
 611              foreach ($proffields as $proffield) {
 612                  $this->customfields[] = 'profile_field_'.$proffield->shortname;
 613              }
 614          }
 615          unset($proffields);
 616  
 617          return $this->customfields;
 618      }
 619  
 620      /**
 621       * Post logout hook.
 622       *
 623       * This method is used after moodle logout by auth classes to execute server logout.
 624       *
 625       * @param stdClass $user clone of USER object before the user session was terminated
 626       */
 627      public function postlogout_hook($user) {
 628      }
 629  
 630      /**
 631       * Update a local user record from an external source.
 632       * This is a lighter version of the one in moodlelib -- won't do
 633       * expensive ops such as enrolment.
 634       *
 635       * @param string $username username
 636       * @param array $updatekeys fields to update, false updates all fields.
 637       * @param bool $triggerevent set false if user_updated event should not be triggered.
 638       *             This will not affect user_password_updated event triggering.
 639       * @param bool $suspenduser Should the user be suspended?
 640       * @return stdClass|bool updated user record or false if there is no new info to update.
 641       */
 642      protected function update_user_record($username, $updatekeys = false, $triggerevent = false, $suspenduser = false) {
 643          global $CFG, $DB;
 644  
 645          require_once($CFG->dirroot.'/user/profile/lib.php');
 646  
 647          // Just in case check text case.
 648          $username = trim(core_text::strtolower($username));
 649  
 650          // Get the current user record.
 651          $user = $DB->get_record('user', array('username' => $username, 'mnethostid' => $CFG->mnet_localhost_id));
 652          if (empty($user)) { // Trouble.
 653              error_log($this->errorlogtag . get_string('auth_usernotexist', 'auth', $username));
 654              print_error('auth_usernotexist', 'auth', '', $username);
 655              die;
 656          }
 657  
 658          // Protect the userid from being overwritten.
 659          $userid = $user->id;
 660  
 661          $needsupdate = false;
 662  
 663          if ($newinfo = $this->get_userinfo($username)) {
 664              $newinfo = truncate_userinfo($newinfo);
 665  
 666              if (empty($updatekeys)) { // All keys? this does not support removing values.
 667                  $updatekeys = array_keys($newinfo);
 668              }
 669  
 670              if (!empty($updatekeys)) {
 671                  $newuser = new stdClass();
 672                  $newuser->id = $userid;
 673                  // The cast to int is a workaround for MDL-53959.
 674                  $newuser->suspended = (int) $suspenduser;
 675                  // Load all custom fields.
 676                  $profilefields = (array) profile_user_record($user->id, false);
 677                  $newprofilefields = [];
 678  
 679                  foreach ($updatekeys as $key) {
 680                      if (isset($newinfo[$key])) {
 681                          $value = $newinfo[$key];
 682                      } else {
 683                          $value = '';
 684                      }
 685  
 686                      if (!empty($this->config->{'field_updatelocal_' . $key})) {
 687                          if (preg_match('/^profile_field_(.*)$/', $key, $match)) {
 688                              // Custom field.
 689                              $field = $match[1];
 690                              $currentvalue = isset($profilefields[$field]) ? $profilefields[$field] : null;
 691                              $newprofilefields[$field] = $value;
 692                          } else {
 693                              // Standard field.
 694                              $currentvalue = isset($user->$key) ? $user->$key : null;
 695                              $newuser->$key = $value;
 696                          }
 697  
 698                          // Only update if it's changed.
 699                          if ($currentvalue !== $value) {
 700                              $needsupdate = true;
 701                          }
 702                      }
 703                  }
 704              }
 705  
 706              if ($needsupdate) {
 707                  user_update_user($newuser, false, $triggerevent);
 708                  profile_save_custom_fields($newuser->id, $newprofilefields);
 709                  return $DB->get_record('user', array('id' => $userid, 'deleted' => 0));
 710              }
 711          }
 712  
 713          return false;
 714      }
 715  
 716      /**
 717       * Return the list of enabled identity providers.
 718       *
 719       * Each identity provider data contains the keys url, name and iconurl (or
 720       * icon). See the documentation of {@link auth_plugin_base::loginpage_idp_list()}
 721       * for detailed description of the returned structure.
 722       *
 723       * @param array $authsequence site's auth sequence (list of auth plugins ordered)
 724       * @return array List of arrays describing the identity providers
 725       */
 726      public static function get_identity_providers($authsequence) {
 727          global $SESSION;
 728  
 729          $identityproviders = [];
 730          foreach ($authsequence as $authname) {
 731              $authplugin = get_auth_plugin($authname);
 732              $wantsurl = (isset($SESSION->wantsurl)) ? $SESSION->wantsurl : '';
 733              $identityproviders = array_merge($identityproviders, $authplugin->loginpage_idp_list($wantsurl));
 734          }
 735          return $identityproviders;
 736      }
 737  
 738      /**
 739       * Prepare a list of identity providers for output.
 740       *
 741       * @param array $identityproviders as returned by {@link self::get_identity_providers()}
 742       * @param renderer_base $output
 743       * @return array the identity providers ready for output
 744       */
 745      public static function prepare_identity_providers_for_output($identityproviders, renderer_base $output) {
 746          $data = [];
 747          foreach ($identityproviders as $idp) {
 748              if (!empty($idp['icon'])) {
 749                  // Pre-3.3 auth plugins provide icon as a pix_icon instance. New auth plugins (since 3.3) provide iconurl.
 750                  $idp['iconurl'] = $output->image_url($idp['icon']->pix, $idp['icon']->component);
 751              }
 752              if ($idp['iconurl'] instanceof moodle_url) {
 753                  $idp['iconurl'] = $idp['iconurl']->out(false);
 754              }
 755              unset($idp['icon']);
 756              if ($idp['url'] instanceof moodle_url) {
 757                  $idp['url'] = $idp['url']->out(false);
 758              }
 759              $data[] = $idp;
 760          }
 761          return $data;
 762      }
 763  
 764      /**
 765       * Returns information on how the specified user can change their password.
 766       *
 767       * @param stdClass $user A user object
 768       * @return string[] An array of strings with keys subject and message
 769       */
 770      public function get_password_change_info(stdClass $user) : array {
 771  
 772          global $USER;
 773  
 774          $site = get_site();
 775          $systemcontext = context_system::instance();
 776  
 777          $data = new stdClass();
 778          $data->firstname = $user->firstname;
 779          $data->lastname  = $user->lastname;
 780          $data->username  = $user->username;
 781          $data->sitename  = format_string($site->fullname);
 782          $data->admin     = generate_email_signoff();
 783  
 784          // This is a workaround as change_password_url() is designed to allow
 785          // use of the $USER global. See MDL-66984.
 786          $olduser = $USER;
 787          $USER = $user;
 788          if ($this->can_change_password() and $this->change_password_url()) {
 789              // We have some external url for password changing.
 790              $data->link = $this->change_password_url()->out();
 791          } else {
 792              // No way to change password, sorry.
 793              $data->link = '';
 794          }
 795          $USER = $olduser;
 796  
 797          if (!empty($data->link) and has_capability('moodle/user:changeownpassword', $systemcontext, $user->id)) {
 798              $subject = get_string('emailpasswordchangeinfosubject', '', format_string($site->fullname));
 799              $message = get_string('emailpasswordchangeinfo', '', $data);
 800          } else {
 801              $subject = get_string('emailpasswordchangeinfosubject', '', format_string($site->fullname));
 802              $message = get_string('emailpasswordchangeinfofail', '', $data);
 803          }
 804  
 805          return [
 806              'subject' => $subject,
 807              'message' => $message
 808          ];
 809      }
 810  }
 811  
 812  /**
 813   * Verify if user is locked out.
 814   *
 815   * @param stdClass $user
 816   * @return bool true if user locked out
 817   */
 818  function login_is_lockedout($user) {
 819      global $CFG;
 820  
 821      if ($user->mnethostid != $CFG->mnet_localhost_id) {
 822          return false;
 823      }
 824      if (isguestuser($user)) {
 825          return false;
 826      }
 827  
 828      if (empty($CFG->lockoutthreshold)) {
 829          // Lockout not enabled.
 830          return false;
 831      }
 832  
 833      if (get_user_preferences('login_lockout_ignored', 0, $user)) {
 834          // This preference may be used for accounts that must not be locked out.
 835          return false;
 836      }
 837  
 838      $locked = get_user_preferences('login_lockout', 0, $user);
 839      if (!$locked) {
 840          return false;
 841      }
 842  
 843      if (empty($CFG->lockoutduration)) {
 844          // Locked out forever.
 845          return true;
 846      }
 847  
 848      if (time() - $locked < $CFG->lockoutduration) {
 849          return true;
 850      }
 851  
 852      login_unlock_account($user);
 853  
 854      return false;
 855  }
 856  
 857  /**
 858   * To be called after valid user login.
 859   * @param stdClass $user
 860   */
 861  function login_attempt_valid($user) {
 862      global $CFG;
 863  
 864      // Note: user_loggedin event is triggered in complete_user_login().
 865  
 866      if ($user->mnethostid != $CFG->mnet_localhost_id) {
 867          return;
 868      }
 869      if (isguestuser($user)) {
 870          return;
 871      }
 872  
 873      // Always unlock here, there might be some race conditions or leftovers when switching threshold.
 874      login_unlock_account($user);
 875  }
 876  
 877  /**
 878   * To be called after failed user login.
 879   * @param stdClass $user
 880   * @throws moodle_exception
 881   */
 882  function login_attempt_failed($user) {
 883      global $CFG;
 884  
 885      if ($user->mnethostid != $CFG->mnet_localhost_id) {
 886          return;
 887      }
 888      if (isguestuser($user)) {
 889          return;
 890      }
 891  
 892      // Force user preferences cache reload to ensure the most up-to-date login_failed_count is fetched.
 893      // This is perhaps overzealous but is the documented way of reloading the cache, as per the test method
 894      // 'test_check_user_preferences_loaded'.
 895      unset($user->preference);
 896  
 897      $resource = 'user:' . $user->id;
 898      $lockfactory = \core\lock\lock_config::get_lock_factory('core_failed_login_count_lock');
 899  
 900      // Get a new lock for the resource, waiting for it for a maximum of 10 seconds.
 901      if ($lock = $lockfactory->get_lock($resource, 10)) {
 902          try {
 903              $count = get_user_preferences('login_failed_count', 0, $user);
 904              $last = get_user_preferences('login_failed_last', 0, $user);
 905              $sincescuccess = get_user_preferences('login_failed_count_since_success', $count, $user);
 906              $sincescuccess = $sincescuccess + 1;
 907              set_user_preference('login_failed_count_since_success', $sincescuccess, $user);
 908  
 909              if (empty($CFG->lockoutthreshold)) {
 910                  // No threshold means no lockout.
 911                  // Always unlock here, there might be some race conditions or leftovers when switching threshold.
 912                  login_unlock_account($user);
 913                  $lock->release();
 914                  return;
 915              }
 916  
 917              if (!empty($CFG->lockoutwindow) and time() - $last > $CFG->lockoutwindow) {
 918                  $count = 0;
 919              }
 920  
 921              $count = $count + 1;
 922  
 923              set_user_preference('login_failed_count', $count, $user);
 924              set_user_preference('login_failed_last', time(), $user);
 925  
 926              if ($count >= $CFG->lockoutthreshold) {
 927                  login_lock_account($user);
 928              }
 929  
 930              // Release locks when we're done.
 931              $lock->release();
 932          } catch (Exception $e) {
 933              // Always release the lock on a failure.
 934              $lock->release();
 935          }
 936      } else {
 937          // We did not get access to the resource in time, give up.
 938          throw new moodle_exception('locktimeout');
 939      }
 940  }
 941  
 942  /**
 943   * Lockout user and send notification email.
 944   *
 945   * @param stdClass $user
 946   */
 947  function login_lock_account($user) {
 948      global $CFG;
 949  
 950      if ($user->mnethostid != $CFG->mnet_localhost_id) {
 951          return;
 952      }
 953      if (isguestuser($user)) {
 954          return;
 955      }
 956  
 957      if (get_user_preferences('login_lockout_ignored', 0, $user)) {
 958          // This user can not be locked out.
 959          return;
 960      }
 961  
 962      $alreadylockedout = get_user_preferences('login_lockout', 0, $user);
 963  
 964      set_user_preference('login_lockout', time(), $user);
 965  
 966      if ($alreadylockedout == 0) {
 967          $secret = random_string(15);
 968          set_user_preference('login_lockout_secret', $secret, $user);
 969  
 970          $oldforcelang = force_current_language($user->lang);
 971  
 972          $site = get_site();
 973          $supportuser = core_user::get_support_user();
 974  
 975          $data = new stdClass();
 976          $data->firstname = $user->firstname;
 977          $data->lastname  = $user->lastname;
 978          $data->username  = $user->username;
 979          $data->sitename  = format_string($site->fullname);
 980          $data->link      = $CFG->wwwroot.'/login/unlock_account.php?u='.$user->id.'&s='.$secret;
 981          $data->admin     = generate_email_signoff();
 982  
 983          $message = get_string('lockoutemailbody', 'admin', $data);
 984          $subject = get_string('lockoutemailsubject', 'admin', format_string($site->fullname));
 985  
 986          if ($message) {
 987              // Directly email rather than using the messaging system to ensure its not routed to a popup or jabber.
 988              email_to_user($user, $supportuser, $subject, $message);
 989          }
 990  
 991          force_current_language($oldforcelang);
 992      }
 993  }
 994  
 995  /**
 996   * Unlock user account and reset timers.
 997   *
 998   * @param stdClass $user
 999   */
1000  function login_unlock_account($user) {
1001      unset_user_preference('login_lockout', $user);
1002      unset_user_preference('login_failed_count', $user);
1003      unset_user_preference('login_failed_last', $user);
1004  
1005      // Note: do not clear the lockout secret because user might click on the link repeatedly.
1006  }
1007  
1008  /**
1009   * Returns whether or not the captcha element is enabled, and the admin settings fulfil its requirements.
1010   * @return bool
1011   */
1012  function signup_captcha_enabled() {
1013      global $CFG;
1014      $authplugin = get_auth_plugin($CFG->registerauth);
1015      return !empty($CFG->recaptchapublickey) && !empty($CFG->recaptchaprivatekey) && $authplugin->is_captcha_enabled();
1016  }
1017  
1018  /**
1019   * Validates the standard sign-up data (except recaptcha that is validated by the form element).
1020   *
1021   * @param  array $data  the sign-up data
1022   * @param  array $files files among the data
1023   * @return array list of errors, being the key the data element name and the value the error itself
1024   * @since Moodle 3.2
1025   */
1026  function signup_validate_data($data, $files) {
1027      global $CFG, $DB;
1028  
1029      $errors = array();
1030      $authplugin = get_auth_plugin($CFG->registerauth);
1031  
1032      if ($DB->record_exists('user', array('username' => $data['username'], 'mnethostid' => $CFG->mnet_localhost_id))) {
1033          $errors['username'] = get_string('usernameexists');
1034      } else {
1035          // Check allowed characters.
1036          if ($data['username'] !== core_text::strtolower($data['username'])) {
1037              $errors['username'] = get_string('usernamelowercase');
1038          } else {
1039              if ($data['username'] !== core_user::clean_field($data['username'], 'username')) {
1040                  $errors['username'] = get_string('invalidusername');
1041              }
1042  
1043          }
1044      }
1045  
1046      // Check if user exists in external db.
1047      // TODO: maybe we should check all enabled plugins instead.
1048      if ($authplugin->user_exists($data['username'])) {
1049          $errors['username'] = get_string('usernameexists');
1050      }
1051  
1052      if (! validate_email($data['email'])) {
1053          $errors['email'] = get_string('invalidemail');
1054  
1055      } else if (empty($CFG->allowaccountssameemail)) {
1056          // Emails in Moodle as case-insensitive and accents-sensitive. Such a combination can lead to very slow queries
1057          // on some DBs such as MySQL. So we first get the list of candidate users in a subselect via more effective
1058          // accent-insensitive query that can make use of the index and only then we search within that limited subset.
1059          $sql = "SELECT 'x'
1060                    FROM {user}
1061                   WHERE " . $DB->sql_equal('email', ':email1', false, true) . "
1062                     AND id IN (SELECT id
1063                                  FROM {user}
1064                                 WHERE " . $DB->sql_equal('email', ':email2', false, false) . "
1065                                   AND mnethostid = :mnethostid)";
1066  
1067          $params = array(
1068              'email1' => $data['email'],
1069              'email2' => $data['email'],
1070              'mnethostid' => $CFG->mnet_localhost_id,
1071          );
1072  
1073          // If there are other user(s) that already have the same email, show an error.
1074          if ($DB->record_exists_sql($sql, $params)) {
1075              $forgotpasswordurl = new moodle_url('/login/forgot_password.php');
1076              $forgotpasswordlink = html_writer::link($forgotpasswordurl, get_string('emailexistshintlink'));
1077              $errors['email'] = get_string('emailexists') . ' ' . get_string('emailexistssignuphint', 'moodle', $forgotpasswordlink);
1078          }
1079      }
1080      if (empty($data['email2'])) {
1081          $errors['email2'] = get_string('missingemail');
1082  
1083      } else if (core_text::strtolower($data['email2']) != core_text::strtolower($data['email'])) {
1084          $errors['email2'] = get_string('invalidemail');
1085      }
1086      if (!isset($errors['email'])) {
1087          if ($err = email_is_not_allowed($data['email'])) {
1088              $errors['email'] = $err;
1089          }
1090      }
1091  
1092      // Construct fake user object to check password policy against required information.
1093      $tempuser = new stdClass();
1094      $tempuser->id = 1;
1095      $tempuser->username = $data['username'];
1096      $tempuser->firstname = $data['firstname'];
1097      $tempuser->lastname = $data['lastname'];
1098      $tempuser->email = $data['email'];
1099  
1100      $errmsg = '';
1101      if (!check_password_policy($data['password'], $errmsg, $tempuser)) {
1102          $errors['password'] = $errmsg;
1103      }
1104  
1105      // Validate customisable profile fields. (profile_validation expects an object as the parameter with userid set).
1106      $dataobject = (object)$data;
1107      $dataobject->id = 0;
1108      $errors += profile_validation($dataobject, $files);
1109  
1110      return $errors;
1111  }
1112  
1113  /**
1114   * Add the missing fields to a user that is going to be created
1115   *
1116   * @param  stdClass $user the new user object
1117   * @return stdClass the user filled
1118   * @since Moodle 3.2
1119   */
1120  function signup_setup_new_user($user) {
1121      global $CFG;
1122  
1123      $user->confirmed   = 0;
1124      $user->lang        = current_language();
1125      $user->firstaccess = 0;
1126      $user->timecreated = time();
1127      $user->mnethostid  = $CFG->mnet_localhost_id;
1128      $user->secret      = random_string(15);
1129      $user->auth        = $CFG->registerauth;
1130      // Initialize alternate name fields to empty strings.
1131      $namefields = array_diff(\core_user\fields::get_name_fields(), useredit_get_required_name_fields());
1132      foreach ($namefields as $namefield) {
1133          $user->$namefield = '';
1134      }
1135      return $user;
1136  }
1137  
1138  /**
1139   * Check if user confirmation is enabled on this site and return the auth plugin handling registration if enabled.
1140   *
1141   * @return stdClass the current auth plugin handling user registration or false if registration not enabled
1142   * @since Moodle 3.2
1143   */
1144  function signup_get_user_confirmation_authplugin() {
1145      global $CFG;
1146  
1147      if (empty($CFG->registerauth)) {
1148          return false;
1149      }
1150      $authplugin = get_auth_plugin($CFG->registerauth);
1151  
1152      if (!$authplugin->can_confirm()) {
1153          return false;
1154      }
1155      return $authplugin;
1156  }
1157  
1158  /**
1159   * Check if sign-up is enabled in the site. If is enabled, the function will return the authplugin instance.
1160   *
1161   * @return mixed false if sign-up is not enabled, the authplugin instance otherwise.
1162   * @since  Moodle 3.2
1163   */
1164  function signup_is_enabled() {
1165      global $CFG;
1166  
1167      if (!empty($CFG->registerauth)) {
1168          $authplugin = get_auth_plugin($CFG->registerauth);
1169          if ($authplugin->can_signup()) {
1170              return $authplugin;
1171          }
1172      }
1173      return false;
1174  }
1175  
1176  /**
1177   * Helper function used to print locking for auth plugins on admin pages.
1178   * @param stdclass $settings Moodle admin settings instance
1179   * @param string $auth authentication plugin shortname
1180   * @param array $userfields user profile fields
1181   * @param string $helptext help text to be displayed at top of form
1182   * @param boolean $mapremotefields Map fields or lock only.
1183   * @param boolean $updateremotefields Allow remote updates
1184   * @param array $customfields list of custom profile fields
1185   * @since Moodle 3.3
1186   */
1187  function display_auth_lock_options($settings, $auth, $userfields, $helptext, $mapremotefields, $updateremotefields, $customfields = array()) {
1188      global $CFG;
1189      require_once($CFG->dirroot . '/user/profile/lib.php');
1190  
1191      // Introductory explanation and help text.
1192      if ($mapremotefields) {
1193          $settings->add(new admin_setting_heading($auth.'/data_mapping', new lang_string('auth_data_mapping', 'auth'), $helptext));
1194      } else {
1195          $settings->add(new admin_setting_heading($auth.'/auth_fieldlocks', new lang_string('auth_fieldlocks', 'auth'), $helptext));
1196      }
1197  
1198      // Generate the list of options.
1199      $lockoptions = array ('unlocked'        => get_string('unlocked', 'auth'),
1200                            'unlockedifempty' => get_string('unlockedifempty', 'auth'),
1201                            'locked'          => get_string('locked', 'auth'));
1202      $updatelocaloptions = array('oncreate'  => get_string('update_oncreate', 'auth'),
1203                                  'onlogin'   => get_string('update_onlogin', 'auth'));
1204      $updateextoptions = array('0'  => get_string('update_never', 'auth'),
1205                                '1'  => get_string('update_onupdate', 'auth'));
1206  
1207      // Generate the list of profile fields to allow updates / lock.
1208      if (!empty($customfields)) {
1209          $userfields = array_merge($userfields, $customfields);
1210          $allcustomfields = profile_get_custom_fields();
1211          $customfieldname = array_combine(array_column($allcustomfields, 'shortname'), $allcustomfields);
1212      }
1213  
1214      foreach ($userfields as $field) {
1215          // Define the fieldname we display to the  user.
1216          // this includes special handling for some profile fields.
1217          $fieldname = $field;
1218          $fieldnametoolong = false;
1219          if ($fieldname === 'lang') {
1220              $fieldname = get_string('language');
1221          } else if (!empty($customfields) && in_array($field, $customfields)) {
1222              // If custom field then pick name from database.
1223              $fieldshortname = str_replace('profile_field_', '', $fieldname);
1224              $fieldname = $customfieldname[$fieldshortname]->name;
1225              if (core_text::strlen($fieldshortname) > 67) {
1226                  // If custom profile field name is longer than 67 characters we will not be able to store the setting
1227                  // such as 'field_updateremote_profile_field_NOTSOSHORTSHORTNAME' in the database because the character
1228                  // limit for the setting name is 100.
1229                  $fieldnametoolong = true;
1230              }
1231          } else {
1232              $fieldname = get_string($fieldname);
1233          }
1234  
1235          // Generate the list of fields / mappings.
1236          if ($fieldnametoolong) {
1237              // Display a message that the field can not be mapped because it's too long.
1238              $url = new moodle_url('/user/profile/index.php');
1239              $a = (object)['fieldname' => s($fieldname), 'shortname' => s($field), 'charlimit' => 67, 'link' => $url->out()];
1240              $settings->add(new admin_setting_heading($auth.'/field_not_mapped_'.sha1($field), '',
1241                  get_string('cannotmapfield', 'auth', $a)));
1242          } else if ($mapremotefields) {
1243              // We are mapping to a remote field here.
1244              // Mapping.
1245              $settings->add(new admin_setting_configtext("auth_{$auth}/field_map_{$field}",
1246                      get_string('auth_fieldmapping', 'auth', $fieldname), '', '', PARAM_RAW, 30));
1247  
1248              // Update local.
1249              $settings->add(new admin_setting_configselect("auth_{$auth}/field_updatelocal_{$field}",
1250                      get_string('auth_updatelocalfield', 'auth', $fieldname), '', 'oncreate', $updatelocaloptions));
1251  
1252              // Update remote.
1253              if ($updateremotefields) {
1254                      $settings->add(new admin_setting_configselect("auth_{$auth}/field_updateremote_{$field}",
1255                          get_string('auth_updateremotefield', 'auth', $fieldname), '', 0, $updateextoptions));
1256              }
1257  
1258              // Lock fields.
1259              $settings->add(new admin_setting_configselect("auth_{$auth}/field_lock_{$field}",
1260                      get_string('auth_fieldlockfield', 'auth', $fieldname), '', 'unlocked', $lockoptions));
1261  
1262          } else {
1263              // Lock fields Only.
1264              $settings->add(new admin_setting_configselect("auth_{$auth}/field_lock_{$field}",
1265                      get_string('auth_fieldlockfield', 'auth', $fieldname), '', 'unlocked', $lockoptions));
1266          }
1267      }
1268  }