lib/authlib.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  * 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     /** @var array Stores extra information available to the logged in event. */
 121     protected $extrauserinfo = [];
 122
 123     /**
 124      * This is the primary method that is used by the authenticate_user_login()
 125      * function in moodlelib.php.
 126      *
 127      * This method should return a boolean indicating
 128      * whether or not the username and password authenticate successfully.
 129      *
 130      * Returns true if the username and password work and false if they are
 131      * wrong or don't exist.
 132      *
 133      * @param string $username The username (with system magic quotes)
 134      * @param string $password The password (with system magic quotes)
 135      *
 136      * @return bool Authentication success or failure.
 137      */
 138     function user_login($username, $password) {
 139         throw new \moodle_exception('mustbeoveride', 'debug', '', 'user_login()' );
 140     }
 141
 142     /**
 143      * Returns true if this authentication plugin can change the users'
 144      * password.
 145      *
 146      * @return bool
 147      */
 148     function can_change_password() {
 149         //override if needed
 150         return false;
 151     }
 152
 153     /**
 154      * Returns the URL for changing the users' passwords, or empty if the default
 155      * URL can be used.
 156      *
 157      * This method is used if can_change_password() returns true.
 158      * This method is called only when user is logged in, it may use global $USER.
 159      * If you are using a plugin config variable in this method, please make sure it is set before using it,
 160      * as this method can be called even if the plugin is disabled, in which case the config values won't be set.
 161      *
 162      * @return moodle_url url of the profile page or null if standard used
 163      */
 164     function change_password_url() {
 165         //override if needed
 166         return null;
 167     }
 168
 169     /**
 170      * Returns true if this authentication plugin can edit the users'
 171      * profile.
 172      *
 173      * @return bool
 174      */
 175     function can_edit_profile() {
 176         //override if needed
 177         return true;
 178     }
 179
 180     /**
 181      * Returns the URL for editing the users' profile, or empty if the default
 182      * URL can be used.
 183      *
 184      * This method is used if can_edit_profile() returns true.
 185      * This method is called only when user is logged in, it may use global $USER.
 186      *
 187      * @return moodle_url url of the profile page or null if standard used
 188      */
 189     function edit_profile_url() {
 190         //override if needed
 191         return null;
 192     }
 193
 194     /**
 195      * Returns true if this authentication plugin is "internal".
 196      *
 197      * Internal plugins use password hashes from Moodle user table for authentication.
 198      *
 199      * @return bool
 200      */
 201     function is_internal() {
 202         //override if needed
 203         return true;
 204     }
 205
 206     /**
 207      * Returns false if this plugin is enabled but not configured.
 208      *
 209      * @return bool
 210      */
 211     public function is_configured() {
 212         return false;
 213     }
 214
 215     /**
 216      * Indicates if password hashes should be stored in local moodle database.
 217      * @return bool true means md5 password hash stored in user table, false means flag 'not_cached' stored there instead
 218      */
 219     function prevent_local_passwords() {
 220         return !$this->is_internal();
 221     }
 222
 223     /**
 224      * Indicates if moodle should automatically update internal user
 225      * records with data from external sources using the information
 226      * from get_userinfo() method.
 227      *
 228      * @return bool true means automatically copy data from ext to user table
 229      */
 230     function is_synchronised_with_external() {
 231         return !$this->is_internal();
 232     }
 233
 234     /**
 235      * Updates the user's password.
 236      *
 237      * In previous versions of Moodle, the function
 238      * auth_user_update_password accepted a username as the first parameter. The
 239      * revised function expects a user object.
 240      *
 241      * @param  object  $user        User table object
 242      * @param  string  $newpassword Plaintext password
 243      *
 244      * @return bool                  True on success
 245      */
 246     function user_update_password($user, $newpassword) {
 247         //override if needed
 248         return true;
 249     }
 250
 251     /**
 252      * Called when the user record is updated.
 253      * Modifies user in external database. It takes olduser (before changes) and newuser (after changes)
 254      * compares information saved modified information to external db.
 255      *
 256      * @param mixed $olduser     Userobject before modifications    (without system magic quotes)
 257      * @param mixed $newuser     Userobject new modified userobject (without system magic quotes)
 258      * @return boolean true if updated or update ignored; false if error
 259      *
 260      */
 261     function user_update($olduser, $newuser) {
 262         //override if needed
 263         return true;
 264     }
 265
 266     /**
 267      * User delete requested - internal user record is mared as deleted already, username not present anymore.
 268      *
 269      * Do any action in external database.
 270      *
 271      * @param object $user       Userobject before delete    (without system magic quotes)
 272      * @return void
 273      */
 274     function user_delete($olduser) {
 275         //override if needed
 276         return;
 277     }
 278
 279     /**
 280      * Returns true if plugin allows resetting of internal password.
 281      *
 282      * @return bool
 283      */
 284     function can_reset_password() {
 285         //override if needed
 286         return false;
 287     }
 288
 289     /**
 290      * Returns true if plugin allows resetting of internal password.
 291      *
 292      * @return bool
 293      */
 294     function can_signup() {
 295         //override if needed
 296         return false;
 297     }
 298
 299     /**
 300      * Sign up a new user ready for confirmation.
 301      * Password is passed in plaintext.
 302      *
 303      * @param object $user new user object
 304      * @param boolean $notify print notice with link and terminate
 305      */
 306     function user_signup($user, $notify=true) {
 307         //override when can signup
 308         throw new \moodle_exception('mustbeoveride', 'debug', '', 'user_signup()' );
 309     }
 310
 311     /**
 312      * Return a form to capture user details for account creation.
 313      * This is used in /login/signup.php.
 314      * @return moodle_form A form which edits a record from the user table.
 315      */
 316     function signup_form() {
 317         global $CFG;
 318
 319         require_once($CFG->dirroot.'/login/signup_form.php');
 320         return new login_signup_form(null, null, 'post', '', array('autocomplete'=>'on'));
 321     }
 322
 323     /**
 324      * Returns true if plugin allows confirming of new users.
 325      *
 326      * @return bool
 327      */
 328     function can_confirm() {
 329         //override if needed
 330         return false;
 331     }
 332
 333     /**
 334      * Confirm the new user as registered.
 335      *
 336      * @param string $username
 337      * @param string $confirmsecret
 338      */
 339     function user_confirm($username, $confirmsecret) {
 340         //override when can confirm
 341         throw new \moodle_exception('mustbeoveride', 'debug', '', 'user_confirm()' );
 342     }
 343
 344     /**
 345      * Checks if user exists in external db
 346      *
 347      * @param string $username (with system magic quotes)
 348      * @return bool
 349      */
 350     function user_exists($username) {
 351         //override if needed
 352         return false;
 353     }
 354
 355     /**
 356      * return number of days to user password expires
 357      *
 358      * If userpassword does not expire it should return 0. If password is already expired
 359      * it should return negative value.
 360      *
 361      * @param mixed $username username (with system magic quotes)
 362      * @return integer
 363      */
 364     function password_expire($username) {
 365         return 0;
 366     }
 367     /**
 368      * Sync roles for this user - usually creator
 369      *
 370      * @param $user object user object (without system magic quotes)
 371      */
 372     function sync_roles($user) {
 373         //override if needed
 374     }
 375
 376     /**
 377      * Read user information from external database and returns it as array().
 378      * Function should return all information available. If you are saving
 379      * this information to moodle user-table you should honour synchronisation flags
 380      *
 381      * @param string $username username
 382      *
 383      * @return mixed array with no magic quotes or false on error
 384      */
 385     function get_userinfo($username) {
 386         //override if needed
 387         return array();
 388     }
 389
 390     /**
 391      * Prints a form for configuring this authentication plugin.
 392      *
 393      * This function is called from admin/auth.php, and outputs a full page with
 394      * a form for configuring this plugin.
 395      *
 396      * @param object $config
 397      * @param object $err
 398      * @param array $user_fields
 399      * @deprecated since Moodle 3.3
 400      */
 401     function config_form($config, $err, $user_fields) {
 402         debugging('Use of config.html files have been deprecated, please update your code to use the admin settings API.');
 403         //override if needed
 404     }
 405
 406     /**
 407      * A chance to validate form data, and last chance to
 408      * do stuff before it is inserted in config_plugin
 409      * @param object object with submitted configuration settings (without system magic quotes)
 410      * @param array $err array of error messages
 411      * @deprecated since Moodle 3.3
 412      */
 413      function validate_form($form, &$err) {
 414         debugging('Use of config.html files have been deprecated, please update your code to use the admin settings API.');
 415         //override if needed
 416     }
 417
 418     /**
 419      * Processes and stores configuration data for this authentication plugin.
 420      *
 421      * @param object object with submitted configuration settings (without system magic quotes)
 422      * @deprecated since Moodle 3.3
 423      */
 424     function process_config($config) {
 425         debugging('Use of config.html files have been deprecated, please update your code to use the admin settings API.');
 426         //override if needed
 427         return true;
 428     }
 429
 430     /**
 431      * Hook for overriding behaviour of login page.
 432      * This method is called from login/index.php page for all enabled auth plugins.
 433      *
 434      * @global object
 435      * @global object
 436      */
 437     function loginpage_hook() {
 438         global $frm;  // can be used to override submitted login form
 439         global $user; // can be used to replace authenticate_user_login()
 440
 441         //override if needed
 442     }
 443
 444     /**
 445      * Hook for overriding behaviour before going to the login page.
 446      *
 447      * This method is called from require_login from potentially any page for
 448      * all enabled auth plugins and gives each plugin a chance to redirect
 449      * directly to an external login page, or to instantly login a user where
 450      * possible.
 451      *
 452      * If an auth plugin implements this hook, it must not rely on ONLY this
 453      * hook in order to work, as there are many ways a user can browse directly
 454      * to the standard login page. As a general rule in this case you should
 455      * also implement the loginpage_hook as well.
 456      *
 457      */
 458     function pre_loginpage_hook() {
 459         // override if needed, eg by redirecting to an external login page
 460         // or logging in a user:
 461         // complete_user_login($user);
 462     }
 463
 464     /**
 465      * Pre user_login hook.
 466      * This method is called from authenticate_user_login() right after the user
 467      * object is generated. This gives the auth plugins an option to make adjustments
 468      * before the verification process starts.
 469      *
 470      * @param object $user user object, later used for $USER
 471      */
 472     public function pre_user_login_hook(&$user) {
 473         // Override if needed.
 474     }
 475
 476     /**
 477      * Post authentication hook.
 478      * This method is called from authenticate_user_login() for all enabled auth plugins.
 479      *
 480      * @param object $user user object, later used for $USER
 481      * @param string $username (with system magic quotes)
 482      * @param string $password plain text password (with system magic quotes)
 483      */
 484     function user_authenticated_hook(&$user, $username, $password) {
 485         //override if needed
 486     }
 487
 488     /**
 489      * Pre logout hook.
 490      * This method is called from require_logout() for all enabled auth plugins,
 491      *
 492      * @global object
 493      */
 494     function prelogout_hook() {
 495         global $USER; // use $USER->auth to find the plugin used for login
 496
 497         //override if needed
 498     }
 499
 500     /**
 501      * Hook for overriding behaviour of logout page.
 502      * This method is called from login/logout.php page for all enabled auth plugins.
 503      *
 504      * @global object
 505      * @global string
 506      */
 507     function logoutpage_hook() {
 508         global $USER;     // use $USER->auth to find the plugin used for login
 509         global $redirect; // can be used to override redirect after logout
 510
 511         //override if needed
 512     }
 513
 514     /**
 515      * Hook called before timing out of database session.
 516      * This is useful for SSO and MNET.
 517      *
 518      * @param object $user
 519      * @param string $sid session id
 520      * @param int $timecreated start of session
 521      * @param int $timemodified user last seen
 522      * @return bool true means do not timeout session yet
 523      */
 524     function ignore_timeout_hook($user, $sid, $timecreated, $timemodified) {
 525         return false;
 526     }
 527
 528     /**
 529      * Return the properly translated human-friendly title of this auth plugin
 530      *
 531      * @todo Document this function
 532      */
 533     function get_title() {
 534         return get_string('pluginname', "auth_{$this->authtype}");
 535     }
 536
 537     /**
 538      * Get the auth description (from core or own auth lang files)
 539      *
 540      * @return string The description
 541      */
 542     function get_description() {
 543         $authdescription = get_string("auth_{$this->authtype}description", "auth_{$this->authtype}");
 544         return $authdescription;
 545     }
 546
 547     /**
 548      * Returns whether or not the captcha element is enabled.
 549      *
 550      * @abstract Implement in child classes
 551      * @return bool
 552      */
 553     function is_captcha_enabled() {
 554         return false;
 555     }
 556
 557     /**
 558      * Returns whether or not this authentication plugin can be manually set
 559      * for users, for example, when bulk uploading users.
 560      *
 561      * This should be overriden by authentication plugins where setting the
 562      * authentication method manually is allowed.
 563      *
 564      * @return bool
 565      * @since Moodle 2.6
 566      */
 567     function can_be_manually_set() {
 568         // Override if needed.
 569         return false;
 570     }
 571
 572     /**
 573      * Returns a list of potential IdPs that this authentication plugin supports.
 574      *
 575      * This is used to provide links on the login page and the login block.
 576      *
 577      * The parameter $wantsurl is typically used by the plugin to implement a
 578      * return-url feature.
 579      *
 580      * The returned value is expected to be a list of associative arrays with
 581      * string keys:
 582      *
 583      * - url => (moodle_url|string) URL of the page to send the user to for authentication
 584      * - name => (string) Human readable name of the IdP
 585      * - iconurl => (moodle_url|string) URL of the icon representing the IdP (since Moodle 3.3)
 586      *
 587      * For legacy reasons, pre-3.3 plugins can provide the icon via the key:
 588      *
 589      * - icon => (pix_icon) Icon representing the IdP
 590      *
 591      * @param string $wantsurl The relative url fragment the user wants to get to.
 592      * @return array List of associative arrays with keys url, name, iconurl|icon
 593      */
 594     function loginpage_idp_list($wantsurl) {
 595         return array();
 596     }
 597
 598     /**
 599      * Return custom user profile fields.
 600      *
 601      * @return array list of custom fields.
 602      */
 603     public function get_custom_user_profile_fields() {
 604         global $CFG;
 605         require_once($CFG->dirroot . '/user/profile/lib.php');
 606
 607         // If already retrieved then return.
 608         if (!is_null($this->customfields)) {
 609             return $this->customfields;
 610         }
 611
 612         $this->customfields = array();
 613         if ($proffields = profile_get_custom_fields()) {
 614             foreach ($proffields as $proffield) {
 615                 $this->customfields[] = 'profile_field_'.$proffield->shortname;
 616             }
 617         }
 618         unset($proffields);
 619
 620         return $this->customfields;
 621     }
 622
 623     /**
 624      * Post logout hook.
 625      *
 626      * This method is used after moodle logout by auth classes to execute server logout.
 627      *
 628      * @param stdClass $user clone of USER object before the user session was terminated
 629      */
 630     public function postlogout_hook($user) {
 631     }
 632
 633     /**
 634      * Update a local user record from an external source.
 635      * This is a lighter version of the one in moodlelib -- won't do
 636      * expensive ops such as enrolment.
 637      *
 638      * @param string $username username
 639      * @param array $updatekeys fields to update, false updates all fields.
 640      * @param bool $triggerevent set false if user_updated event should not be triggered.
 641      *             This will not affect user_password_updated event triggering.
 642      * @param bool $suspenduser Should the user be suspended?
 643      * @return stdClass|bool updated user record or false if there is no new info to update.
 644      */
 645     protected function update_user_record($username, $updatekeys = false, $triggerevent = false, $suspenduser = false) {
 646         global $CFG, $DB;
 647
 648         require_once($CFG->dirroot.'/user/profile/lib.php');
 649
 650         // Just in case check text case.
 651         $username = trim(core_text::strtolower($username));
 652
 653         // Get the current user record.
 654         $user = $DB->get_record('user', array('username' => $username, 'mnethostid' => $CFG->mnet_localhost_id));
 655         if (empty($user)) { // Trouble.
 656             error_log($this->errorlogtag . get_string('auth_usernotexist', 'auth', $username));
 657             throw new \moodle_exception('auth_usernotexist', 'auth', '', $username);
 658             die;
 659         }
 660
 661         // Protect the userid from being overwritten.
 662         $userid = $user->id;
 663
 664         $needsupdate = false;
 665
 666         if ($newinfo = $this->get_userinfo($username)) {
 667             $newinfo = truncate_userinfo($newinfo);
 668
 669             if (empty($updatekeys)) { // All keys? this does not support removing values.
 670                 $updatekeys = array_keys($newinfo);
 671             }
 672
 673             if (!empty($updatekeys)) {
 674                 $newuser = new stdClass();
 675                 $newuser->id = $userid;
 676                 // The cast to int is a workaround for MDL-53959.
 677                 $newuser->suspended = (int) $suspenduser;
 678                 // Load all custom fields.
 679                 $profilefields = (array) profile_user_record($user->id, false);
 680                 $newprofilefields = [];
 681
 682                 foreach ($updatekeys as $key) {
 683                     if (isset($newinfo[$key])) {
 684                         $value = $newinfo[$key];
 685                     } else {
 686                         $value = '';
 687                     }
 688
 689                     if (!empty($this->config->{'field_updatelocal_' . $key})) {
 690                         if (preg_match('/^profile_field_(.*)$/', $key, $match)) {
 691                             // Custom field.
 692                             $field = $match[1];
 693                             $currentvalue = isset($profilefields[$field]) ? $profilefields[$field] : null;
 694                             $newprofilefields[$field] = $value;
 695                         } else {
 696                             // Standard field.
 697                             $currentvalue = isset($user->$key) ? $user->$key : null;
 698                             $newuser->$key = $value;
 699                         }
 700
 701                         // Only update if it's changed.
 702                         if ($currentvalue !== $value) {
 703                             $needsupdate = true;
 704                         }
 705                     }
 706                 }
 707             }
 708
 709             if ($needsupdate) {
 710                 user_update_user($newuser, false, $triggerevent);
 711                 profile_save_custom_fields($newuser->id, $newprofilefields);
 712                 return $DB->get_record('user', array('id' => $userid, 'deleted' => 0));
 713             }
 714         }
 715
 716         return false;
 717     }
 718
 719     /**
 720      * Return the list of enabled identity providers.
 721      *
 722      * Each identity provider data contains the keys url, name and iconurl (or
 723      * icon). See the documentation of {@link auth_plugin_base::loginpage_idp_list()}
 724      * for detailed description of the returned structure.
 725      *
 726      * @param array $authsequence site's auth sequence (list of auth plugins ordered)
 727      * @return array List of arrays describing the identity providers
 728      */
 729     public static function get_identity_providers($authsequence) {
 730         global $SESSION;
 731
 732         $identityproviders = [];
 733         foreach ($authsequence as $authname) {
 734             $authplugin = get_auth_plugin($authname);
 735             $wantsurl = (isset($SESSION->wantsurl)) ? $SESSION->wantsurl : '';
 736             $identityproviders = array_merge($identityproviders, $authplugin->loginpage_idp_list($wantsurl));
 737         }
 738         return $identityproviders;
 739     }
 740
 741     /**
 742      * Prepare a list of identity providers for output.
 743      *
 744      * @param array $identityproviders as returned by {@link self::get_identity_providers()}
 745      * @param renderer_base $output
 746      * @return array the identity providers ready for output
 747      */
 748     public static function prepare_identity_providers_for_output($identityproviders, renderer_base $output) {
 749         $data = [];
 750         foreach ($identityproviders as $idp) {
 751             if (!empty($idp['icon'])) {
 752                 // Pre-3.3 auth plugins provide icon as a pix_icon instance. New auth plugins (since 3.3) provide iconurl.
 753                 $idp['iconurl'] = $output->image_url($idp['icon']->pix, $idp['icon']->component);
 754             }
 755             if ($idp['iconurl'] instanceof moodle_url) {
 756                 $idp['iconurl'] = $idp['iconurl']->out(false);
 757             }
 758             unset($idp['icon']);
 759             if ($idp['url'] instanceof moodle_url) {
 760                 $idp['url'] = $idp['url']->out(false);
 761             }
 762             $data[] = $idp;
 763         }
 764         return $data;
 765     }
 766
 767     /**
 768      * Returns information on how the specified user can change their password.
 769      *
 770      * @param stdClass $user A user object
 771      * @return string[] An array of strings with keys subject and message
 772      */
 773     public function get_password_change_info(stdClass $user) : array {
 774
 775         global $USER;
 776
 777         $site = get_site();
 778         $systemcontext = context_system::instance();
 779
 780         $data = new stdClass();
 781         $data->firstname = $user->firstname;
 782         $data->lastname  = $user->lastname;
 783         $data->username  = $user->username;
 784         $data->sitename  = format_string($site->fullname);
 785         $data->admin     = generate_email_signoff();
 786
 787         // This is a workaround as change_password_url() is designed to allow
 788         // use of the $USER global. See MDL-66984.
 789         $olduser = $USER;
 790         $USER = $user;
 791         if ($this->can_change_password() and $this->change_password_url()) {
 792             // We have some external url for password changing.
 793             $data->link = $this->change_password_url()->out();
 794         } else {
 795             // No way to change password, sorry.
 796             $data->link = '';
 797         }
 798         $USER = $olduser;
 799
 800         if (!empty($data->link) and has_capability('moodle/user:changeownpassword', $systemcontext, $user->id)) {
 801             $subject = get_string('emailpasswordchangeinfosubject', '', format_string($site->fullname));
 802             $message = get_string('emailpasswordchangeinfo', '', $data);
 803         } else {
 804             $subject = get_string('emailpasswordchangeinfosubject', '', format_string($site->fullname));
 805             $message = get_string('emailpasswordchangeinfofail', '', $data);
 806         }
 807
 808         return [
 809             'subject' => $subject,
 810             'message' => $message
 811         ];
 812     }
 813
 814     /**
 815      * Set extra user information.
 816      *
 817      * @param array $values Any Key value pair.
 818      * @return void
 819      */
 820     public function set_extrauserinfo(array $values): void {
 821         $this->extrauserinfo = $values;
 822     }
 823
 824     /**
 825      * Returns extra user information.
 826      *
 827      * @return array An array of keys and values
 828      */
 829     public function get_extrauserinfo(): array {
 830         return $this->extrauserinfo;
 831     }
 832 }
 833
 834 /**
 835  * Verify if user is locked out.
 836  *
 837  * @param stdClass $user
 838  * @return bool true if user locked out
 839  */
 840 function login_is_lockedout($user) {
 841     global $CFG;
 842
 843     if ($user->mnethostid != $CFG->mnet_localhost_id) {
 844         return false;
 845     }
 846     if (isguestuser($user)) {
 847         return false;
 848     }
 849
 850     if (empty($CFG->lockoutthreshold)) {
 851         // Lockout not enabled.
 852         return false;
 853     }
 854
 855     if (get_user_preferences('login_lockout_ignored', 0, $user)) {
 856         // This preference may be used for accounts that must not be locked out.
 857         return false;
 858     }
 859
 860     $locked = get_user_preferences('login_lockout', 0, $user);
 861     if (!$locked) {
 862         return false;
 863     }
 864
 865     if (empty($CFG->lockoutduration)) {
 866         // Locked out forever.
 867         return true;
 868     }
 869
 870     if (time() - $locked < $CFG->lockoutduration) {
 871         return true;
 872     }
 873
 874     login_unlock_account($user);
 875
 876     return false;
 877 }
 878
 879 /**
 880  * To be called after valid user login.
 881  * @param stdClass $user
 882  */
 883 function login_attempt_valid($user) {
 884     global $CFG;
 885
 886     // Note: user_loggedin event is triggered in complete_user_login().
 887
 888     if ($user->mnethostid != $CFG->mnet_localhost_id) {
 889         return;
 890     }
 891     if (isguestuser($user)) {
 892         return;
 893     }
 894
 895     // Always unlock here, there might be some race conditions or leftovers when switching threshold.
 896     login_unlock_account($user);
 897 }
 898
 899 /**
 900  * To be called after failed user login.
 901  * @param stdClass $user
 902  * @throws moodle_exception
 903  */
 904 function login_attempt_failed($user) {
 905     global $CFG;
 906
 907     if ($user->mnethostid != $CFG->mnet_localhost_id) {
 908         return;
 909     }
 910     if (isguestuser($user)) {
 911         return;
 912     }
 913
 914     // Force user preferences cache reload to ensure the most up-to-date login_failed_count is fetched.
 915     // This is perhaps overzealous but is the documented way of reloading the cache, as per the test method
 916     // 'test_check_user_preferences_loaded'.
 917     unset($user->preference);
 918
 919     $resource = 'user:' . $user->id;
 920     $lockfactory = \core\lock\lock_config::get_lock_factory('core_failed_login_count_lock');
 921
 922     // Get a new lock for the resource, waiting for it for a maximum of 10 seconds.
 923     if ($lock = $lockfactory->get_lock($resource, 10)) {
 924         try {
 925             $count = get_user_preferences('login_failed_count', 0, $user);
 926             $last = get_user_preferences('login_failed_last', 0, $user);
 927             $sincescuccess = get_user_preferences('login_failed_count_since_success', $count, $user);
 928             $sincescuccess = $sincescuccess + 1;
 929             set_user_preference('login_failed_count_since_success', $sincescuccess, $user);
 930
 931             if (empty($CFG->lockoutthreshold)) {
 932                 // No threshold means no lockout.
 933                 // Always unlock here, there might be some race conditions or leftovers when switching threshold.
 934                 login_unlock_account($user);
 935                 $lock->release();
 936                 return;
 937             }
 938
 939             if (!empty($CFG->lockoutwindow) and time() - $last > $CFG->lockoutwindow) {
 940                 $count = 0;
 941             }
 942
 943             $count = $count + 1;
 944
 945             set_user_preference('login_failed_count', $count, $user);
 946             set_user_preference('login_failed_last', time(), $user);
 947
 948             if ($count >= $CFG->lockoutthreshold) {
 949                 login_lock_account($user);
 950             }
 951
 952             // Release locks when we're done.
 953             $lock->release();
 954         } catch (Exception $e) {
 955             // Always release the lock on a failure.
 956             $lock->release();
 957         }
 958     } else {
 959         // We did not get access to the resource in time, give up.
 960         throw new moodle_exception('locktimeout');
 961     }
 962 }
 963
 964 /**
 965  * Lockout user and send notification email.
 966  *
 967  * @param stdClass $user
 968  */
 969 function login_lock_account($user) {
 970     global $CFG;
 971
 972     if ($user->mnethostid != $CFG->mnet_localhost_id) {
 973         return;
 974     }
 975     if (isguestuser($user)) {
 976         return;
 977     }
 978
 979     if (get_user_preferences('login_lockout_ignored', 0, $user)) {
 980         // This user can not be locked out.
 981         return;
 982     }
 983
 984     $alreadylockedout = get_user_preferences('login_lockout', 0, $user);
 985
 986     set_user_preference('login_lockout', time(), $user);
 987
 988     if ($alreadylockedout == 0) {
 989         $secret = random_string(15);
 990         set_user_preference('login_lockout_secret', $secret, $user);
 991
 992         $oldforcelang = force_current_language($user->lang);
 993
 994         $site = get_site();
 995         $supportuser = core_user::get_support_user();
 996
 997         $data = new stdClass();
 998         $data->firstname = $user->firstname;
 999         $data->lastname  = $user->lastname;
1000         $data->username  = $user->username;
1001         $data->sitename  = format_string($site->fullname);
1002         $data->link      = $CFG->wwwroot.'/login/unlock_account.php?u='.$user->id.'&s='.$secret;
1003         $data->admin     = generate_email_signoff();
1004
1005         $message = get_string('lockoutemailbody', 'admin', $data);
1006         $subject = get_string('lockoutemailsubject', 'admin', format_string($site->fullname));
1007
1008         if ($message) {
1009             // Directly email rather than using the messaging system to ensure its not routed to a popup or jabber.
1010             email_to_user($user, $supportuser, $subject, $message);
1011         }
1012
1013         force_current_language($oldforcelang);
1014     }
1015 }
1016
1017 /**
1018  * Unlock user account and reset timers.
1019  *
1020  * @param stdClass $user
1021  */
1022 function login_unlock_account($user) {
1023     unset_user_preference('login_lockout', $user);
1024     unset_user_preference('login_failed_count', $user);
1025     unset_user_preference('login_failed_last', $user);
1026
1027     // Note: do not clear the lockout secret because user might click on the link repeatedly.
1028 }
1029
1030 /**
1031  * Returns whether or not the captcha element is enabled, and the admin settings fulfil its requirements.
1032  * @return bool
1033  */
1034 function signup_captcha_enabled() {
1035     global $CFG;
1036     $authplugin = get_auth_plugin($CFG->registerauth);
1037     return !empty($CFG->recaptchapublickey) && !empty($CFG->recaptchaprivatekey) && $authplugin->is_captcha_enabled();
1038 }
1039
1040 /**
1041  * Validates the standard sign-up data (except recaptcha that is validated by the form element).
1042  *
1043  * @param  array $data  the sign-up data
1044  * @param  array $files files among the data
1045  * @return array list of errors, being the key the data element name and the value the error itself
1046  * @since Moodle 3.2
1047  */
1048 function signup_validate_data($data, $files) {
1049     global $CFG, $DB;
1050
1051     $errors = array();
1052     $authplugin = get_auth_plugin($CFG->registerauth);
1053
1054     if ($DB->record_exists('user', array('username' => $data['username'], 'mnethostid' => $CFG->mnet_localhost_id))) {
1055         $errors['username'] = get_string('usernameexists');
1056     } else {
1057         // Check allowed characters.
1058         if ($data['username'] !== core_text::strtolower($data['username'])) {
1059             $errors['username'] = get_string('usernamelowercase');
1060         } else {
1061             if ($data['username'] !== core_user::clean_field($data['username'], 'username')) {
1062                 $errors['username'] = get_string('invalidusername');
1063             }
1064
1065         }
1066     }
1067
1068     // Check if user exists in external db.
1069     // TODO: maybe we should check all enabled plugins instead.
1070     if ($authplugin->user_exists($data['username'])) {
1071         $errors['username'] = get_string('usernameexists');
1072     }
1073
1074     if (! validate_email($data['email'])) {
1075         $errors['email'] = get_string('invalidemail');
1076
1077     } else if (empty($CFG->allowaccountssameemail)) {
1078         // Emails in Moodle as case-insensitive and accents-sensitive. Such a combination can lead to very slow queries
1079         // on some DBs such as MySQL. So we first get the list of candidate users in a subselect via more effective
1080         // accent-insensitive query that can make use of the index and only then we search within that limited subset.
1081         $sql = "SELECT 'x'
1082                   FROM {user}
1083                  WHERE " . $DB->sql_equal('email', ':email1', false, true) . "
1084                    AND id IN (SELECT id
1085                                 FROM {user}
1086                                WHERE " . $DB->sql_equal('email', ':email2', false, false) . "
1087                                  AND mnethostid = :mnethostid)";
1088
1089         $params = array(
1090             'email1' => $data['email'],
1091             'email2' => $data['email'],
1092             'mnethostid' => $CFG->mnet_localhost_id,
1093         );
1094
1095         // If there are other user(s) that already have the same email, show an error.
1096         if ($DB->record_exists_sql($sql, $params)) {
1097             $forgotpasswordurl = new moodle_url('/login/forgot_password.php');
1098             $forgotpasswordlink = html_writer::link($forgotpasswordurl, get_string('emailexistshintlink'));
1099             $errors['email'] = get_string('emailexists') . ' ' . get_string('emailexistssignuphint', 'moodle', $forgotpasswordlink);
1100         }
1101     }
1102     if (empty($data['email2'])) {
1103         $errors['email2'] = get_string('missingemail');
1104
1105     } else if (core_text::strtolower($data['email2']) != core_text::strtolower($data['email'])) {
1106         $errors['email2'] = get_string('invalidemail');
1107     }
1108     if (!isset($errors['email'])) {
1109         if ($err = email_is_not_allowed($data['email'])) {
1110             $errors['email'] = $err;
1111         }
1112     }
1113
1114     // Construct fake user object to check password policy against required information.
1115     $tempuser = new stdClass();
1116     $tempuser->id = 1;
1117     $tempuser->username = $data['username'];
1118     $tempuser->firstname = $data['firstname'];
1119     $tempuser->lastname = $data['lastname'];
1120     $tempuser->email = $data['email'];
1121
1122     $errmsg = '';
1123     if (!check_password_policy($data['password'], $errmsg, $tempuser)) {
1124         $errors['password'] = $errmsg;
1125     }
1126
1127     // Validate customisable profile fields. (profile_validation expects an object as the parameter with userid set).
1128     $dataobject = (object)$data;
1129     $dataobject->id = 0;
1130     $errors += profile_validation($dataobject, $files);
1131
1132     return $errors;
1133 }
1134
1135 /**
1136  * Add the missing fields to a user that is going to be created
1137  *
1138  * @param  stdClass $user the new user object
1139  * @return stdClass the user filled
1140  * @since Moodle 3.2
1141  */
1142 function signup_setup_new_user($user) {
1143     global $CFG;
1144
1145     $user->confirmed   = 0;
1146     $user->lang        = current_language();
1147     $user->firstaccess = 0;
1148     $user->timecreated = time();
1149     $user->mnethostid  = $CFG->mnet_localhost_id;
1150     $user->secret      = random_string(15);
1151     $user->auth        = $CFG->registerauth;
1152     // Initialize alternate name fields to empty strings.
1153     $namefields = array_diff(\core_user\fields::get_name_fields(), useredit_get_required_name_fields());
1154     foreach ($namefields as $namefield) {
1155         $user->$namefield = '';
1156     }
1157     return $user;
1158 }
1159
1160 /**
1161  * Check if user confirmation is enabled on this site and return the auth plugin handling registration if enabled.
1162  *
1163  * @return stdClass the current auth plugin handling user registration or false if registration not enabled
1164  * @since Moodle 3.2
1165  */
1166 function signup_get_user_confirmation_authplugin() {
1167     global $CFG;
1168
1169     if (empty($CFG->registerauth)) {
1170         return false;
1171     }
1172     $authplugin = get_auth_plugin($CFG->registerauth);
1173
1174     if (!$authplugin->can_confirm()) {
1175         return false;
1176     }
1177     return $authplugin;
1178 }
1179
1180 /**
1181  * Check if sign-up is enabled in the site. If is enabled, the function will return the authplugin instance.
1182  *
1183  * @return mixed false if sign-up is not enabled, the authplugin instance otherwise.
1184  * @since  Moodle 3.2
1185  */
1186 function signup_is_enabled() {
1187     global $CFG;
1188
1189     if (!empty($CFG->registerauth)) {
1190         $authplugin = get_auth_plugin($CFG->registerauth);
1191         if ($authplugin->can_signup()) {
1192             return $authplugin;
1193         }
1194     }
1195     return false;
1196 }
1197
1198 /**
1199  * Helper function used to print locking for auth plugins on admin pages.
1200  * @param stdclass $settings Moodle admin settings instance
1201  * @param string $auth authentication plugin shortname
1202  * @param array $userfields user profile fields
1203  * @param string $helptext help text to be displayed at top of form
1204  * @param boolean $mapremotefields Map fields or lock only.
1205  * @param boolean $updateremotefields Allow remote updates
1206  * @param array $customfields list of custom profile fields
1207  * @since Moodle 3.3
1208  */
1209 function display_auth_lock_options($settings, $auth, $userfields, $helptext, $mapremotefields, $updateremotefields, $customfields = array()) {
1210     global $CFG;
1211     require_once($CFG->dirroot . '/user/profile/lib.php');
1212
1213     // Introductory explanation and help text.
1214     if ($mapremotefields) {
1215         $settings->add(new admin_setting_heading($auth.'/data_mapping', new lang_string('auth_data_mapping', 'auth'), $helptext));
1216     } else {
1217         $settings->add(new admin_setting_heading($auth.'/auth_fieldlocks', new lang_string('auth_fieldlocks', 'auth'), $helptext));
1218     }
1219
1220     // Generate the list of options.
1221     $lockoptions = array ('unlocked'        => get_string('unlocked', 'auth'),
1222                           'unlockedifempty' => get_string('unlockedifempty', 'auth'),
1223                           'locked'          => get_string('locked', 'auth'));
1224     $updatelocaloptions = array('oncreate'  => get_string('update_oncreate', 'auth'),
1225                                 'onlogin'   => get_string('update_onlogin', 'auth'));
1226     $updateextoptions = array('0'  => get_string('update_never', 'auth'),
1227                               '1'  => get_string('update_onupdate', 'auth'));
1228
1229     // Generate the list of profile fields to allow updates / lock.
1230     if (!empty($customfields)) {
1231         $userfields = array_merge($userfields, $customfields);
1232         $allcustomfields = profile_get_custom_fields();
1233         $customfieldname = array_combine(array_column($allcustomfields, 'shortname'), $allcustomfields);
1234     }
1235
1236     foreach ($userfields as $field) {
1237         // Define the fieldname we display to the  user.
1238         // this includes special handling for some profile fields.
1239         $fieldname = $field;
1240         $fieldnametoolong = false;
1241         if ($fieldname === 'lang') {
1242             $fieldname = get_string('language');
1243         } else if (!empty($customfields) && in_array($field, $customfields)) {
1244             // If custom field then pick name from database.
1245             $fieldshortname = str_replace('profile_field_', '', $fieldname);
1246             $fieldname = $customfieldname[$fieldshortname]->name;
1247             if (core_text::strlen($fieldshortname) > 67) {
1248                 // If custom profile field name is longer than 67 characters we will not be able to store the setting
1249                 // such as 'field_updateremote_profile_field_NOTSOSHORTSHORTNAME' in the database because the character
1250                 // limit for the setting name is 100.
1251                 $fieldnametoolong = true;
1252             }
1253         } else {
1254             $fieldname = get_string($fieldname);
1255         }
1256
1257         // Generate the list of fields / mappings.
1258         if ($fieldnametoolong) {
1259             // Display a message that the field can not be mapped because it's too long.
1260             $url = new moodle_url('/user/profile/index.php');
1261             $a = (object)['fieldname' => s($fieldname), 'shortname' => s($field), 'charlimit' => 67, 'link' => $url->out()];
1262             $settings->add(new admin_setting_heading($auth.'/field_not_mapped_'.sha1($field), '',
1263                 get_string('cannotmapfield', 'auth', $a)));
1264         } else if ($mapremotefields) {
1265             // We are mapping to a remote field here.
1266             // Mapping.
1267             $settings->add(new admin_setting_configtext("auth_{$auth}/field_map_{$field}",
1268                     get_string('auth_fieldmapping', 'auth', $fieldname), '', '', PARAM_RAW, 30));
1269
1270             // Update local.
1271             $settings->add(new admin_setting_configselect("auth_{$auth}/field_updatelocal_{$field}",
1272                     get_string('auth_updatelocalfield', 'auth', $fieldname), '', 'oncreate', $updatelocaloptions));
1273
1274             // Update remote.
1275             if ($updateremotefields) {
1276                     $settings->add(new admin_setting_configselect("auth_{$auth}/field_updateremote_{$field}",
1277                         get_string('auth_updateremotefield', 'auth', $fieldname), '', 0, $updateextoptions));
1278             }
1279
1280             // Lock fields.
1281             $settings->add(new admin_setting_configselect("auth_{$auth}/field_lock_{$field}",
1282                     get_string('auth_fieldlockfield', 'auth', $fieldname), '', 'unlocked', $lockoptions));
1283
1284         } else {
1285             // Lock fields Only.
1286             $settings->add(new admin_setting_configselect("auth_{$auth}/field_lock_{$field}",
1287                     get_string('auth_fieldlockfield', 'auth', $fieldname), '', 'unlocked', $lockoptions));
1288         }
1289     }
1290 }