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 /** Can not login, failed reCaptcha challenge. */
  83 define('AUTH_LOGIN_FAILED_RECAPTCHA', 6);
  84
  85 /**
  86  * Abstract authentication plugin.
  87  *
  88  * @license http://www.gnu.org/copyleft/gpl.html GNU GPL v3 or later
  89  * @package moodlecore
  90  */
  91 class auth_plugin_base {
  92
  93     /**
  94      * The configuration details for the plugin.
  95      * @var object
  96      */
  97     var $config;
  98
  99     /**
 100      * Authentication plugin type - the same as db field.
 101      * @var string
 102      */
 103     var $authtype;
 104     /*
 105      * The fields we can lock and update from/to external authentication backends
 106      * @var array
 107      */
 108     var $userfields = \core_user::AUTHSYNCFIELDS;
 109
 110     /**
 111      * Moodle custom fields to sync with.
 112      * @var array()
 113      */
 114     var $customfields = null;
 115
 116     /**
 117      * The tag we want to prepend to any error log messages.
 118      *
 119      * @var string
 120      */
 121     protected $errorlogtag = '';
 122
 123     /** @var array Stores extra information available to the logged in event. */
 124     protected $extrauserinfo = [];
 125
 126     /**
 127      * This is the primary method that is used by the authenticate_user_login()
 128      * function in moodlelib.php.
 129      *
 130      * This method should return a boolean indicating
 131      * whether or not the username and password authenticate successfully.
 132      *
 133      * Returns true if the username and password work and false if they are
 134      * wrong or don't exist.
 135      *
 136      * @param string $username The username (with system magic quotes)
 137      * @param string $password The password (with system magic quotes)
 138      *
 139      * @return bool Authentication success or failure.
 140      */
 141     function user_login($username, $password) {
 142         throw new \moodle_exception('mustbeoveride', 'debug', '', 'user_login()' );
 143     }
 144
 145     /**
 146      * Returns true if this authentication plugin can change the users'
 147      * password.
 148      *
 149      * @return bool
 150      */
 151     function can_change_password() {
 152         //override if needed
 153         return false;
 154     }
 155
 156     /**
 157      * Returns the URL for changing the users' passwords, or empty if the default
 158      * URL can be used.
 159      *
 160      * This method is used if can_change_password() returns true.
 161      * This method is called only when user is logged in, it may use global $USER.
 162      * If you are using a plugin config variable in this method, please make sure it is set before using it,
 163      * as this method can be called even if the plugin is disabled, in which case the config values won't be set.
 164      *
 165      * @return moodle_url url of the profile page or null if standard used
 166      */
 167     function change_password_url() {
 168         //override if needed
 169         return null;
 170     }
 171
 172     /**
 173      * Returns true if this authentication plugin can edit the users'
 174      * profile.
 175      *
 176      * @return bool
 177      */
 178     function can_edit_profile() {
 179         //override if needed
 180         return true;
 181     }
 182
 183     /**
 184      * Returns the URL for editing the users' profile, or empty if the default
 185      * URL can be used.
 186      *
 187      * This method is used if can_edit_profile() returns true.
 188      * This method is called only when user is logged in, it may use global $USER.
 189      *
 190      * @return moodle_url url of the profile page or null if standard used
 191      */
 192     function edit_profile_url() {
 193         //override if needed
 194         return null;
 195     }
 196
 197     /**
 198      * Returns true if this authentication plugin is "internal".
 199      *
 200      * Internal plugins use password hashes from Moodle user table for authentication.
 201      *
 202      * @return bool
 203      */
 204     function is_internal() {
 205         //override if needed
 206         return true;
 207     }
 208
 209     /**
 210      * Returns false if this plugin is enabled but not configured.
 211      *
 212      * @return bool
 213      */
 214     public function is_configured() {
 215         return false;
 216     }
 217
 218     /**
 219      * Indicates if password hashes should be stored in local moodle database.
 220      * @return bool true means md5 password hash stored in user table, false means flag 'not_cached' stored there instead
 221      */
 222     function prevent_local_passwords() {
 223         return !$this->is_internal();
 224     }
 225
 226     /**
 227      * Indicates if moodle should automatically update internal user
 228      * records with data from external sources using the information
 229      * from get_userinfo() method.
 230      *
 231      * @return bool true means automatically copy data from ext to user table
 232      */
 233     function is_synchronised_with_external() {
 234         return !$this->is_internal();
 235     }
 236
 237     /**
 238      * Updates the user's password.
 239      *
 240      * In previous versions of Moodle, the function
 241      * auth_user_update_password accepted a username as the first parameter. The
 242      * revised function expects a user object.
 243      *
 244      * @param  object  $user        User table object
 245      * @param  string  $newpassword Plaintext password
 246      *
 247      * @return bool                  True on success
 248      */
 249     function user_update_password($user, $newpassword) {
 250         //override if needed
 251         return true;
 252     }
 253
 254     /**
 255      * Called when the user record is updated.
 256      * Modifies user in external database. It takes olduser (before changes) and newuser (after changes)
 257      * compares information saved modified information to external db.
 258      *
 259      * @param mixed $olduser     Userobject before modifications    (without system magic quotes)
 260      * @param mixed $newuser     Userobject new modified userobject (without system magic quotes)
 261      * @return boolean true if updated or update ignored; false if error
 262      *
 263      */
 264     function user_update($olduser, $newuser) {
 265         //override if needed
 266         return true;
 267     }
 268
 269     /**
 270      * User delete requested - internal user record is mared as deleted already, username not present anymore.
 271      *
 272      * Do any action in external database.
 273      *
 274      * @param object $user       Userobject before delete    (without system magic quotes)
 275      * @return void
 276      */
 277     function user_delete($olduser) {
 278         //override if needed
 279         return;
 280     }
 281
 282     /**
 283      * Returns true if plugin allows resetting of internal password.
 284      *
 285      * @return bool
 286      */
 287     function can_reset_password() {
 288         //override if needed
 289         return false;
 290     }
 291
 292     /**
 293      * Returns true if plugin allows resetting of internal password.
 294      *
 295      * @return bool
 296      */
 297     function can_signup() {
 298         //override if needed
 299         return false;
 300     }
 301
 302     /**
 303      * Sign up a new user ready for confirmation.
 304      * Password is passed in plaintext.
 305      *
 306      * @param object $user new user object
 307      * @param boolean $notify print notice with link and terminate
 308      */
 309     function user_signup($user, $notify=true) {
 310         //override when can signup
 311         throw new \moodle_exception('mustbeoveride', 'debug', '', 'user_signup()' );
 312     }
 313
 314     /**
 315      * Return a form to capture user details for account creation.
 316      * This is used in /login/signup.php.
 317      * @return moodle_form A form which edits a record from the user table.
 318      */
 319     function signup_form() {
 320         global $CFG;
 321
 322         require_once($CFG->dirroot.'/login/signup_form.php');
 323         return new login_signup_form(null, null, 'post', '', array('autocomplete'=>'on'));
 324     }
 325
 326     /**
 327      * Returns true if plugin allows confirming of new users.
 328      *
 329      * @return bool
 330      */
 331     function can_confirm() {
 332         //override if needed
 333         return false;
 334     }
 335
 336     /**
 337      * Confirm the new user as registered.
 338      *
 339      * @param string $username
 340      * @param string $confirmsecret
 341      */
 342     function user_confirm($username, $confirmsecret) {
 343         //override when can confirm
 344         throw new \moodle_exception('mustbeoveride', 'debug', '', 'user_confirm()' );
 345     }
 346
 347     /**
 348      * Checks if user exists in external db
 349      *
 350      * @param string $username (with system magic quotes)
 351      * @return bool
 352      */
 353     function user_exists($username) {
 354         //override if needed
 355         return false;
 356     }
 357
 358     /**
 359      * return number of days to user password expires
 360      *
 361      * If userpassword does not expire it should return 0. If password is already expired
 362      * it should return negative value.
 363      *
 364      * @param mixed $username username (with system magic quotes)
 365      * @return integer
 366      */
 367     function password_expire($username) {
 368         return 0;
 369     }
 370     /**
 371      * Sync roles for this user - usually creator
 372      *
 373      * @param $user object user object (without system magic quotes)
 374      */
 375     function sync_roles($user) {
 376         //override if needed
 377     }
 378
 379     /**
 380      * Read user information from external database and returns it as array().
 381      * Function should return all information available. If you are saving
 382      * this information to moodle user-table you should honour synchronisation flags
 383      *
 384      * @param string $username username
 385      *
 386      * @return mixed array with no magic quotes or false on error
 387      */
 388     function get_userinfo($username) {
 389         //override if needed
 390         return array();
 391     }
 392
 393     /**
 394      * Prints a form for configuring this authentication plugin.
 395      *
 396      * This function is called from admin/auth.php, and outputs a full page with
 397      * a form for configuring this plugin.
 398      *
 399      * @param object $config
 400      * @param object $err
 401      * @param array $user_fields
 402      * @deprecated since Moodle 3.3
 403      */
 404     function config_form($config, $err, $user_fields) {
 405         debugging('Use of config.html files have been deprecated, please update your code to use the admin settings API.');
 406         //override if needed
 407     }
 408
 409     /**
 410      * A chance to validate form data, and last chance to
 411      * do stuff before it is inserted in config_plugin
 412      * @param object object with submitted configuration settings (without system magic quotes)
 413      * @param array $err array of error messages
 414      * @deprecated since Moodle 3.3
 415      */
 416      function validate_form($form, &$err) {
 417         debugging('Use of config.html files have been deprecated, please update your code to use the admin settings API.');
 418         //override if needed
 419     }
 420
 421     /**
 422      * Processes and stores configuration data for this authentication plugin.
 423      *
 424      * @param object object with submitted configuration settings (without system magic quotes)
 425      * @deprecated since Moodle 3.3
 426      */
 427     function process_config($config) {
 428         debugging('Use of config.html files have been deprecated, please update your code to use the admin settings API.');
 429         //override if needed
 430         return true;
 431     }
 432
 433     /**
 434      * Hook for overriding behaviour of login page.
 435      * This method is called from login/index.php page for all enabled auth plugins.
 436      *
 437      * @global object
 438      * @global object
 439      */
 440     function loginpage_hook() {
 441         global $frm;  // can be used to override submitted login form
 442         global $user; // can be used to replace authenticate_user_login()
 443
 444         //override if needed
 445     }
 446
 447     /**
 448      * Hook for overriding behaviour before going to the login page.
 449      *
 450      * This method is called from require_login from potentially any page for
 451      * all enabled auth plugins and gives each plugin a chance to redirect
 452      * directly to an external login page, or to instantly login a user where
 453      * possible.
 454      *
 455      * If an auth plugin implements this hook, it must not rely on ONLY this
 456      * hook in order to work, as there are many ways a user can browse directly
 457      * to the standard login page. As a general rule in this case you should
 458      * also implement the loginpage_hook as well.
 459      *
 460      */
 461     function pre_loginpage_hook() {
 462         // override if needed, eg by redirecting to an external login page
 463         // or logging in a user:
 464         // complete_user_login($user);
 465     }
 466
 467     /**
 468      * Pre user_login hook.
 469      * This method is called from authenticate_user_login() right after the user
 470      * object is generated. This gives the auth plugins an option to make adjustments
 471      * before the verification process starts.
 472      *
 473      * @param object $user user object, later used for $USER
 474      */
 475     public function pre_user_login_hook(&$user) {
 476         // Override if needed.
 477     }
 478
 479     /**
 480      * Post authentication hook.
 481      * This method is called from authenticate_user_login() for all enabled auth plugins.
 482      *
 483      * @param object $user user object, later used for $USER
 484      * @param string $username (with system magic quotes)
 485      * @param string $password plain text password (with system magic quotes)
 486      */
 487     function user_authenticated_hook(&$user, $username, $password) {
 488         //override if needed
 489     }
 490
 491     /**
 492      * Pre logout hook.
 493      * This method is called from require_logout() for all enabled auth plugins,
 494      *
 495      * @global object
 496      */
 497     function prelogout_hook() {
 498         global $USER; // use $USER->auth to find the plugin used for login
 499
 500         //override if needed
 501     }
 502
 503     /**
 504      * Hook for overriding behaviour of logout page.
 505      * This method is called from login/logout.php page for all enabled auth plugins.
 506      *
 507      * @global object
 508      * @global string
 509      */
 510     function logoutpage_hook() {
 511         global $USER;     // use $USER->auth to find the plugin used for login
 512         global $redirect; // can be used to override redirect after logout
 513
 514         //override if needed
 515     }
 516
 517     /**
 518      * Hook called before timing out of database session.
 519      * This is useful for SSO and MNET.
 520      *
 521      * @param object $user
 522      * @param string $sid session id
 523      * @param int $timecreated start of session
 524      * @param int $timemodified user last seen
 525      * @return bool true means do not timeout session yet
 526      */
 527     function ignore_timeout_hook($user, $sid, $timecreated, $timemodified) {
 528         return false;
 529     }
 530
 531     /**
 532      * Return the properly translated human-friendly title of this auth plugin
 533      *
 534      * @todo Document this function
 535      */
 536     function get_title() {
 537         return get_string('pluginname', "auth_{$this->authtype}");
 538     }
 539
 540     /**
 541      * Get the auth description (from core or own auth lang files)
 542      *
 543      * @return string The description
 544      */
 545     function get_description() {
 546         $authdescription = get_string("auth_{$this->authtype}description", "auth_{$this->authtype}");
 547         return $authdescription;
 548     }
 549
 550     /**
 551      * Returns whether or not the captcha element is enabled.
 552      *
 553      * @abstract Implement in child classes
 554      * @return bool
 555      */
 556     function is_captcha_enabled() {
 557         return false;
 558     }
 559
 560     /**
 561      * Returns whether or not this authentication plugin can be manually set
 562      * for users, for example, when bulk uploading users.
 563      *
 564      * This should be overriden by authentication plugins where setting the
 565      * authentication method manually is allowed.
 566      *
 567      * @return bool
 568      * @since Moodle 2.6
 569      */
 570     function can_be_manually_set() {
 571         // Override if needed.
 572         return false;
 573     }
 574
 575     /**
 576      * Returns a list of potential IdPs that this authentication plugin supports.
 577      *
 578      * This is used to provide links on the login page and the login block.
 579      *
 580      * The parameter $wantsurl is typically used by the plugin to implement a
 581      * return-url feature.
 582      *
 583      * The returned value is expected to be a list of associative arrays with
 584      * string keys:
 585      *
 586      * - url => (moodle_url|string) URL of the page to send the user to for authentication
 587      * - name => (string) Human readable name of the IdP
 588      * - iconurl => (moodle_url|string) URL of the icon representing the IdP (since Moodle 3.3)
 589      *
 590      * For legacy reasons, pre-3.3 plugins can provide the icon via the key:
 591      *
 592      * - icon => (pix_icon) Icon representing the IdP
 593      *
 594      * @param string $wantsurl The relative url fragment the user wants to get to.
 595      * @return array List of associative arrays with keys url, name, iconurl|icon
 596      */
 597     function loginpage_idp_list($wantsurl) {
 598         return array();
 599     }
 600
 601     /**
 602      * Return custom user profile fields.
 603      *
 604      * @return array list of custom fields.
 605      */
 606     public function get_custom_user_profile_fields() {
 607         global $CFG;
 608         require_once($CFG->dirroot . '/user/profile/lib.php');
 609
 610         // If already retrieved then return.
 611         if (!is_null($this->customfields)) {
 612             return $this->customfields;
 613         }
 614
 615         $this->customfields = array();
 616         if ($proffields = profile_get_custom_fields()) {
 617             foreach ($proffields as $proffield) {
 618                 $this->customfields[] = 'profile_field_'.$proffield->shortname;
 619             }
 620         }
 621         unset($proffields);
 622
 623         return $this->customfields;
 624     }
 625
 626     /**
 627      * Post logout hook.
 628      *
 629      * This method is used after moodle logout by auth classes to execute server logout.
 630      *
 631      * @param stdClass $user clone of USER object before the user session was terminated
 632      */
 633     public function postlogout_hook($user) {
 634     }
 635
 636     /**
 637      * Update a local user record from an external source.
 638      * This is a lighter version of the one in moodlelib -- won't do
 639      * expensive ops such as enrolment.
 640      *
 641      * @param string $username username
 642      * @param array $updatekeys fields to update, false updates all fields.
 643      * @param bool $triggerevent set false if user_updated event should not be triggered.
 644      *             This will not affect user_password_updated event triggering.
 645      * @param bool $suspenduser Should the user be suspended?
 646      * @return stdClass|bool updated user record or false if there is no new info to update.
 647      */
 648     protected function update_user_record($username, $updatekeys = false, $triggerevent = false, $suspenduser = false) {
 649         global $CFG, $DB;
 650
 651         require_once($CFG->dirroot.'/user/profile/lib.php');
 652
 653         // Just in case check text case.
 654         $username = trim(core_text::strtolower($username));
 655
 656         // Get the current user record.
 657         $user = $DB->get_record('user', array('username' => $username, 'mnethostid' => $CFG->mnet_localhost_id));
 658         if (empty($user)) { // Trouble.
 659             error_log($this->errorlogtag . get_string('auth_usernotexist', 'auth', $username));
 660             throw new \moodle_exception('auth_usernotexist', 'auth', '', $username);
 661             die;
 662         }
 663
 664         // Protect the userid from being overwritten.
 665         $userid = $user->id;
 666
 667         $needsupdate = false;
 668
 669         if ($newinfo = $this->get_userinfo($username)) {
 670             $newinfo = truncate_userinfo($newinfo);
 671
 672             if (empty($updatekeys)) { // All keys? this does not support removing values.
 673                 $updatekeys = array_keys($newinfo);
 674             }
 675
 676             if (!empty($updatekeys)) {
 677                 $newuser = new stdClass();
 678                 $newuser->id = $userid;
 679                 // The cast to int is a workaround for MDL-53959.
 680                 $newuser->suspended = (int) $suspenduser;
 681                 // Load all custom fields.
 682                 $profilefields = (array) profile_user_record($user->id, false);
 683                 $newprofilefields = [];
 684
 685                 foreach ($updatekeys as $key) {
 686                     if (isset($newinfo[$key])) {
 687                         $value = $newinfo[$key];
 688                     } else {
 689                         $value = '';
 690                     }
 691
 692                     if (!empty($this->config->{'field_updatelocal_' . $key})) {
 693                         if (preg_match('/^profile_field_(.*)$/', $key, $match)) {
 694                             // Custom field.
 695                             $field = $match[1];
 696                             $currentvalue = isset($profilefields[$field]) ? $profilefields[$field] : null;
 697                             $newprofilefields[$field] = $value;
 698                         } else {
 699                             // Standard field.
 700                             $currentvalue = isset($user->$key) ? $user->$key : null;
 701                             $newuser->$key = $value;
 702                         }
 703
 704                         // Only update if it's changed.
 705                         if ($currentvalue !== $value) {
 706                             $needsupdate = true;
 707                         }
 708                     }
 709                 }
 710             }
 711
 712             if ($needsupdate) {
 713                 user_update_user($newuser, false, $triggerevent);
 714                 profile_save_custom_fields($newuser->id, $newprofilefields);
 715                 return $DB->get_record('user', array('id' => $userid, 'deleted' => 0));
 716             }
 717         }
 718
 719         return false;
 720     }
 721
 722     /**
 723      * Return the list of enabled identity providers.
 724      *
 725      * Each identity provider data contains the keys url, name and iconurl (or
 726      * icon). See the documentation of {@link auth_plugin_base::loginpage_idp_list()}
 727      * for detailed description of the returned structure.
 728      *
 729      * @param array $authsequence site's auth sequence (list of auth plugins ordered)
 730      * @return array List of arrays describing the identity providers
 731      */
 732     public static function get_identity_providers($authsequence) {
 733         global $SESSION;
 734
 735         $identityproviders = [];
 736         foreach ($authsequence as $authname) {
 737             $authplugin = get_auth_plugin($authname);
 738             $wantsurl = (isset($SESSION->wantsurl)) ? $SESSION->wantsurl : '';
 739             $identityproviders = array_merge($identityproviders, $authplugin->loginpage_idp_list($wantsurl));
 740         }
 741         return $identityproviders;
 742     }
 743
 744     /**
 745      * Prepare a list of identity providers for output.
 746      *
 747      * @param array $identityproviders as returned by {@link self::get_identity_providers()}
 748      * @param renderer_base $output
 749      * @return array the identity providers ready for output
 750      */
 751     public static function prepare_identity_providers_for_output($identityproviders, renderer_base $output) {
 752         $data = [];
 753         foreach ($identityproviders as $idp) {
 754             if (!empty($idp['icon'])) {
 755                 // Pre-3.3 auth plugins provide icon as a pix_icon instance. New auth plugins (since 3.3) provide iconurl.
 756                 $idp['iconurl'] = $output->image_url($idp['icon']->pix, $idp['icon']->component);
 757             }
 758             if ($idp['iconurl'] instanceof moodle_url) {
 759                 $idp['iconurl'] = $idp['iconurl']->out(false);
 760             }
 761             unset($idp['icon']);
 762             if ($idp['url'] instanceof moodle_url) {
 763                 $idp['url'] = $idp['url']->out(false);
 764             }
 765             $data[] = $idp;
 766         }
 767         return $data;
 768     }
 769
 770     /**
 771      * Returns information on how the specified user can change their password.
 772      *
 773      * @param stdClass $user A user object
 774      * @return string[] An array of strings with keys subject and message
 775      */
 776     public function get_password_change_info(stdClass $user) : array {
 777
 778         global $USER;
 779
 780         $site = get_site();
 781         $systemcontext = context_system::instance();
 782
 783         $data = new stdClass();
 784         $data->firstname = $user->firstname;
 785         $data->lastname  = $user->lastname;
 786         $data->username  = $user->username;
 787         $data->sitename  = format_string($site->fullname);
 788         $data->admin     = generate_email_signoff();
 789
 790         // This is a workaround as change_password_url() is designed to allow
 791         // use of the $USER global. See MDL-66984.
 792         $olduser = $USER;
 793         $USER = $user;
 794         if ($this->can_change_password() and $this->change_password_url()) {
 795             // We have some external url for password changing.
 796             $data->link = $this->change_password_url()->out();
 797         } else {
 798             // No way to change password, sorry.
 799             $data->link = '';
 800         }
 801         $USER = $olduser;
 802
 803         if (!empty($data->link) and has_capability('moodle/user:changeownpassword', $systemcontext, $user->id)) {
 804             $subject = get_string('emailpasswordchangeinfosubject', '', format_string($site->fullname));
 805             $message = get_string('emailpasswordchangeinfo', '', $data);
 806         } else {
 807             $subject = get_string('emailpasswordchangeinfosubject', '', format_string($site->fullname));
 808             $message = get_string('emailpasswordchangeinfofail', '', $data);
 809         }
 810
 811         return [
 812             'subject' => $subject,
 813             'message' => $message
 814         ];
 815     }
 816
 817     /**
 818      * Set extra user information.
 819      *
 820      * @param array $values Any Key value pair.
 821      * @return void
 822      */
 823     public function set_extrauserinfo(array $values): void {
 824         $this->extrauserinfo = $values;
 825     }
 826
 827     /**
 828      * Returns extra user information.
 829      *
 830      * @return array An array of keys and values
 831      */
 832     public function get_extrauserinfo(): array {
 833         return $this->extrauserinfo;
 834     }
 835 }
 836
 837 /**
 838  * Verify if user is locked out.
 839  *
 840  * @param stdClass $user
 841  * @return bool true if user locked out
 842  */
 843 function login_is_lockedout($user) {
 844     global $CFG;
 845
 846     if ($user->mnethostid != $CFG->mnet_localhost_id) {
 847         return false;
 848     }
 849     if (isguestuser($user)) {
 850         return false;
 851     }
 852
 853     if (empty($CFG->lockoutthreshold)) {
 854         // Lockout not enabled.
 855         return false;
 856     }
 857
 858     if (get_user_preferences('login_lockout_ignored', 0, $user)) {
 859         // This preference may be used for accounts that must not be locked out.
 860         return false;
 861     }
 862
 863     $locked = get_user_preferences('login_lockout', 0, $user);
 864     if (!$locked) {
 865         return false;
 866     }
 867
 868     if (empty($CFG->lockoutduration)) {
 869         // Locked out forever.
 870         return true;
 871     }
 872
 873     if (time() - $locked < $CFG->lockoutduration) {
 874         return true;
 875     }
 876
 877     login_unlock_account($user);
 878
 879     return false;
 880 }
 881
 882 /**
 883  * To be called after valid user login.
 884  * @param stdClass $user
 885  */
 886 function login_attempt_valid($user) {
 887     global $CFG;
 888
 889     // Note: user_loggedin event is triggered in complete_user_login().
 890
 891     if ($user->mnethostid != $CFG->mnet_localhost_id) {
 892         return;
 893     }
 894     if (isguestuser($user)) {
 895         return;
 896     }
 897
 898     // Always unlock here, there might be some race conditions or leftovers when switching threshold.
 899     login_unlock_account($user);
 900 }
 901
 902 /**
 903  * To be called after failed user login.
 904  * @param stdClass $user
 905  * @throws moodle_exception
 906  */
 907 function login_attempt_failed($user) {
 908     global $CFG;
 909
 910     if ($user->mnethostid != $CFG->mnet_localhost_id) {
 911         return;
 912     }
 913     if (isguestuser($user)) {
 914         return;
 915     }
 916
 917     // Force user preferences cache reload to ensure the most up-to-date login_failed_count is fetched.
 918     // This is perhaps overzealous but is the documented way of reloading the cache, as per the test method
 919     // 'test_check_user_preferences_loaded'.
 920     unset($user->preference);
 921
 922     $resource = 'user:' . $user->id;
 923     $lockfactory = \core\lock\lock_config::get_lock_factory('core_failed_login_count_lock');
 924
 925     // Get a new lock for the resource, waiting for it for a maximum of 10 seconds.
 926     if ($lock = $lockfactory->get_lock($resource, 10)) {
 927         try {
 928             $count = get_user_preferences('login_failed_count', 0, $user);
 929             $last = get_user_preferences('login_failed_last', 0, $user);
 930             $sincescuccess = get_user_preferences('login_failed_count_since_success', $count, $user);
 931             $sincescuccess = $sincescuccess + 1;
 932             set_user_preference('login_failed_count_since_success', $sincescuccess, $user);
 933
 934             if (empty($CFG->lockoutthreshold)) {
 935                 // No threshold means no lockout.
 936                 // Always unlock here, there might be some race conditions or leftovers when switching threshold.
 937                 login_unlock_account($user);
 938                 $lock->release();
 939                 return;
 940             }
 941
 942             if (!empty($CFG->lockoutwindow) and time() - $last > $CFG->lockoutwindow) {
 943                 $count = 0;
 944             }
 945
 946             $count = $count + 1;
 947
 948             set_user_preference('login_failed_count', $count, $user);
 949             set_user_preference('login_failed_last', time(), $user);
 950
 951             if ($count >= $CFG->lockoutthreshold) {
 952                 login_lock_account($user);
 953             }
 954
 955             // Release locks when we're done.
 956             $lock->release();
 957         } catch (Exception $e) {
 958             // Always release the lock on a failure.
 959             $lock->release();
 960         }
 961     } else {
 962         // We did not get access to the resource in time, give up.
 963         throw new moodle_exception('locktimeout');
 964     }
 965 }
 966
 967 /**
 968  * Lockout user and send notification email.
 969  *
 970  * @param stdClass $user
 971  */
 972 function login_lock_account($user) {
 973     global $CFG;
 974
 975     if ($user->mnethostid != $CFG->mnet_localhost_id) {
 976         return;
 977     }
 978     if (isguestuser($user)) {
 979         return;
 980     }
 981
 982     if (get_user_preferences('login_lockout_ignored', 0, $user)) {
 983         // This user can not be locked out.
 984         return;
 985     }
 986
 987     $alreadylockedout = get_user_preferences('login_lockout', 0, $user);
 988
 989     set_user_preference('login_lockout', time(), $user);
 990
 991     if ($alreadylockedout == 0) {
 992         $secret = random_string(15);
 993         set_user_preference('login_lockout_secret', $secret, $user);
 994
 995         $oldforcelang = force_current_language($user->lang);
 996
 997         $site = get_site();
 998         $supportuser = core_user::get_support_user();
 999
1000         $data = new stdClass();
1001         $data->firstname = $user->firstname;
1002         $data->lastname  = $user->lastname;
1003         $data->username  = $user->username;
1004         $data->sitename  = format_string($site->fullname);
1005         $data->link      = $CFG->wwwroot.'/login/unlock_account.php?u='.$user->id.'&s='.$secret;
1006         $data->admin     = generate_email_signoff();
1007
1008         $message = get_string('lockoutemailbody', 'admin', $data);
1009         $subject = get_string('lockoutemailsubject', 'admin', format_string($site->fullname));
1010
1011         if ($message) {
1012             // Directly email rather than using the messaging system to ensure its not routed to a popup or jabber.
1013             email_to_user($user, $supportuser, $subject, $message);
1014         }
1015
1016         force_current_language($oldforcelang);
1017     }
1018 }
1019
1020 /**
1021  * Unlock user account and reset timers.
1022  *
1023  * @param stdClass $user
1024  * @param bool $notify Notify the user their account has been unlocked.
1025  */
1026 function login_unlock_account($user, bool $notify = false) {
1027     global $SESSION;
1028
1029     unset_user_preference('login_lockout', $user);
1030     unset_user_preference('login_failed_count', $user);
1031     unset_user_preference('login_failed_last', $user);
1032
1033     if ($notify) {
1034         $SESSION->logininfomsg = get_string('accountunlocked', 'admin');
1035     }
1036     // Note: do not clear the lockout secret because user might click on the link repeatedly.
1037 }
1038
1039 /**
1040  * Returns whether or not the captcha element is enabled, and the admin settings fulfil its requirements.
1041  * @return bool
1042  */
1043 function signup_captcha_enabled() {
1044     global $CFG;
1045     $authplugin = get_auth_plugin($CFG->registerauth);
1046     return !empty($CFG->recaptchapublickey) && !empty($CFG->recaptchaprivatekey) && $authplugin->is_captcha_enabled();
1047 }
1048
1049 /**
1050  * Returns whether the captcha element is enabled for the login form, and the admin settings fulfil its requirements.
1051  * @return bool
1052  */
1053 function login_captcha_enabled(): bool {
1054     global $CFG;
1055     return !empty($CFG->recaptchapublickey) && !empty($CFG->recaptchaprivatekey) && $CFG->enableloginrecaptcha == true;
1056 }
1057
1058 /**
1059  * Check the submitted captcha is valid or not.
1060  *
1061  * @param string|bool $captcha The value submitted in the login form that we are validating.
1062  *                             If false is passed for the captcha, this function will always return true.
1063  * @return boolean If the submitted captcha is valid.
1064  */
1065 function validate_login_captcha(string|bool $captcha): bool {
1066     global $CFG;
1067     if (!empty($CFG->alternateloginurl)) {
1068         // An external login page cannot use the reCaptcha.
1069         return true;
1070     }
1071     if ($captcha === false) {
1072         // The authenticate_user_login() is a core function was extended to validate captcha.
1073         // For existing uses other than the login form it does not need to validate the captcha.
1074         // Example: login/change_password_form.php or login/token.php.
1075         return true;
1076     }
1077
1078     require_once($CFG->libdir . '/recaptchalib_v2.php');
1079     $response = recaptcha_check_response(RECAPTCHA_VERIFY_URL, $CFG->recaptchaprivatekey, getremoteaddr(), $captcha);
1080     return $response['isvalid'];
1081 }
1082
1083 /**
1084  * Validates the standard sign-up data (except recaptcha that is validated by the form element).
1085  *
1086  * @param  array $data  the sign-up data
1087  * @param  array $files files among the data
1088  * @return array list of errors, being the key the data element name and the value the error itself
1089  * @since Moodle 3.2
1090  */
1091 function signup_validate_data($data, $files) {
1092     global $CFG, $DB;
1093
1094     $errors = array();
1095     $authplugin = get_auth_plugin($CFG->registerauth);
1096
1097     if ($DB->record_exists('user', array('username' => $data['username'], 'mnethostid' => $CFG->mnet_localhost_id))) {
1098         $errors['username'] = get_string('usernameexists');
1099     } else {
1100         // Check allowed characters.
1101         if ($data['username'] !== core_text::strtolower($data['username'])) {
1102             $errors['username'] = get_string('usernamelowercase');
1103         } else {
1104             if ($data['username'] !== core_user::clean_field($data['username'], 'username')) {
1105                 $errors['username'] = get_string('invalidusername');
1106             }
1107
1108         }
1109     }
1110
1111     // Check if user exists in external db.
1112     // TODO: maybe we should check all enabled plugins instead.
1113     if ($authplugin->user_exists($data['username'])) {
1114         $errors['username'] = get_string('usernameexists');
1115     }
1116
1117     if (! validate_email($data['email'])) {
1118         $errors['email'] = get_string('invalidemail');
1119
1120     } else if (empty($CFG->allowaccountssameemail)) {
1121         // Emails in Moodle as case-insensitive and accents-sensitive. Such a combination can lead to very slow queries
1122         // on some DBs such as MySQL. So we first get the list of candidate users in a subselect via more effective
1123         // accent-insensitive query that can make use of the index and only then we search within that limited subset.
1124         $sql = "SELECT 'x'
1125                   FROM {user}
1126                  WHERE " . $DB->sql_equal('email', ':email1', false, true) . "
1127                    AND id IN (SELECT id
1128                                 FROM {user}
1129                                WHERE " . $DB->sql_equal('email', ':email2', false, false) . "
1130                                  AND mnethostid = :mnethostid)";
1131
1132         $params = array(
1133             'email1' => $data['email'],
1134             'email2' => $data['email'],
1135             'mnethostid' => $CFG->mnet_localhost_id,
1136         );
1137
1138         // If there are other user(s) that already have the same email, show an error.
1139         if ($DB->record_exists_sql($sql, $params)) {
1140             $forgotpasswordurl = new moodle_url('/login/forgot_password.php');
1141             $forgotpasswordlink = html_writer::link($forgotpasswordurl, get_string('emailexistshintlink'));
1142             $errors['email'] = get_string('emailexists') . ' ' . get_string('emailexistssignuphint', 'moodle', $forgotpasswordlink);
1143         }
1144     }
1145     if (empty($data['email2'])) {
1146         $errors['email2'] = get_string('missingemail');
1147
1148     } else if (core_text::strtolower($data['email2']) != core_text::strtolower($data['email'])) {
1149         $errors['email2'] = get_string('invalidemail');
1150     }
1151     if (!isset($errors['email'])) {
1152         if ($err = email_is_not_allowed($data['email'])) {
1153             $errors['email'] = $err;
1154         }
1155     }
1156
1157     // Construct fake user object to check password policy against required information.
1158     $tempuser = new stdClass();
1159     // To prevent errors with check_password_policy(),
1160     // the temporary user and the guest must not share the same ID.
1161     $tempuser->id = (int)$CFG->siteguest + 1;
1162     $tempuser->username = $data['username'];
1163     $tempuser->firstname = $data['firstname'];
1164     $tempuser->lastname = $data['lastname'];
1165     $tempuser->email = $data['email'];
1166
1167     $errmsg = '';
1168     if (!check_password_policy($data['password'], $errmsg, $tempuser)) {
1169         $errors['password'] = $errmsg;
1170     }
1171
1172     // Validate customisable profile fields. (profile_validation expects an object as the parameter with userid set).
1173     $dataobject = (object)$data;
1174     $dataobject->id = 0;
1175     $errors += profile_validation($dataobject, $files);
1176
1177     return $errors;
1178 }
1179
1180 /**
1181  * Add the missing fields to a user that is going to be created
1182  *
1183  * @param  stdClass $user the new user object
1184  * @return stdClass the user filled
1185  * @since Moodle 3.2
1186  */
1187 function signup_setup_new_user($user) {
1188     global $CFG;
1189
1190     $user->confirmed   = 0;
1191     $user->lang        = current_language();
1192     $user->firstaccess = 0;
1193     $user->timecreated = time();
1194     $user->mnethostid  = $CFG->mnet_localhost_id;
1195     $user->secret      = random_string(15);
1196     $user->auth        = $CFG->registerauth;
1197     // Initialize alternate name fields to empty strings.
1198     $namefields = array_diff(\core_user\fields::get_name_fields(), useredit_get_required_name_fields());
1199     foreach ($namefields as $namefield) {
1200         $user->$namefield = '';
1201     }
1202     return $user;
1203 }
1204
1205 /**
1206  * Check if user confirmation is enabled on this site and return the auth plugin handling registration if enabled.
1207  *
1208  * @return stdClass the current auth plugin handling user registration or false if registration not enabled
1209  * @since Moodle 3.2
1210  */
1211 function signup_get_user_confirmation_authplugin() {
1212     global $CFG;
1213
1214     if (empty($CFG->registerauth)) {
1215         return false;
1216     }
1217     $authplugin = get_auth_plugin($CFG->registerauth);
1218
1219     if (!$authplugin->can_confirm()) {
1220         return false;
1221     }
1222     return $authplugin;
1223 }
1224
1225 /**
1226  * Check if sign-up is enabled in the site. If is enabled, the function will return the authplugin instance.
1227  *
1228  * @return mixed false if sign-up is not enabled, the authplugin instance otherwise.
1229  * @since  Moodle 3.2
1230  */
1231 function signup_is_enabled() {
1232     global $CFG;
1233
1234     if (!empty($CFG->registerauth)) {
1235         $authplugin = get_auth_plugin($CFG->registerauth);
1236         if ($authplugin->can_signup()) {
1237             return $authplugin;
1238         }
1239     }
1240     return false;
1241 }
1242
1243 /**
1244  * Helper function used to print locking for auth plugins on admin pages.
1245  * @param admin_settingpage $settings Moodle admin settings instance
1246  * @param string $auth authentication plugin shortname
1247  * @param array $userfields user profile fields
1248  * @param string $helptext help text to be displayed at top of form
1249  * @param boolean $mapremotefields Map fields or lock only.
1250  * @param boolean $updateremotefields Allow remote updates
1251  * @param array $customfields list of custom profile fields
1252  * @since Moodle 3.3
1253  */
1254 function display_auth_lock_options($settings, $auth, $userfields, $helptext, $mapremotefields, $updateremotefields, $customfields = array()) {
1255     global $CFG;
1256     require_once($CFG->dirroot . '/user/profile/lib.php');
1257
1258     // Introductory explanation and help text.
1259     if ($mapremotefields) {
1260         $settings->add(new admin_setting_heading($auth.'/data_mapping', new lang_string('auth_data_mapping', 'auth'), $helptext));
1261     } else {
1262         $settings->add(new admin_setting_heading($auth.'/auth_fieldlocks', new lang_string('auth_fieldlocks', 'auth'), $helptext));
1263     }
1264
1265     // Generate the list of options.
1266     $lockoptions = array ('unlocked'        => get_string('unlocked', 'auth'),
1267                           'unlockedifempty' => get_string('unlockedifempty', 'auth'),
1268                           'locked'          => get_string('locked', 'auth'));
1269     $updatelocaloptions = array('oncreate'  => get_string('update_oncreate', 'auth'),
1270                                 'onlogin'   => get_string('update_onlogin', 'auth'));
1271     $updateextoptions = array('0'  => get_string('update_never', 'auth'),
1272                               '1'  => get_string('update_onupdate', 'auth'));
1273
1274     // Generate the list of profile fields to allow updates / lock.
1275     if (!empty($customfields)) {
1276         $userfields = array_merge($userfields, $customfields);
1277         $allcustomfields = profile_get_custom_fields();
1278         $customfieldname = array_combine(array_column($allcustomfields, 'shortname'), $allcustomfields);
1279     }
1280
1281     foreach ($userfields as $field) {
1282         // Define the fieldname we display to the  user.
1283         // this includes special handling for some profile fields.
1284         $fieldname = $field;
1285         $fieldnametoolong = false;
1286         if ($fieldname === 'lang') {
1287             $fieldname = get_string('language');
1288         } else if (!empty($customfields) && in_array($field, $customfields)) {
1289             // If custom field then pick name from database.
1290             $fieldshortname = str_replace('profile_field_', '', $fieldname);
1291             $fieldname = $customfieldname[$fieldshortname]->name;
1292             if (core_text::strlen($fieldshortname) > 67) {
1293                 // If custom profile field name is longer than 67 characters we will not be able to store the setting
1294                 // such as 'field_updateremote_profile_field_NOTSOSHORTSHORTNAME' in the database because the character
1295                 // limit for the setting name is 100.
1296                 $fieldnametoolong = true;
1297             }
1298         } else {
1299             $fieldname = get_string($fieldname);
1300         }
1301
1302         // Generate the list of fields / mappings.
1303         if ($fieldnametoolong) {
1304             // Display a message that the field can not be mapped because it's too long.
1305             $url = new moodle_url('/user/profile/index.php');
1306             $a = (object)['fieldname' => s($fieldname), 'shortname' => s($field), 'charlimit' => 67, 'link' => $url->out()];
1307             $settings->add(new admin_setting_heading($auth.'/field_not_mapped_'.sha1($field), '',
1308                 get_string('cannotmapfield', 'auth', $a)));
1309         } else if ($mapremotefields) {
1310             // We are mapping to a remote field here.
1311             // Mapping.
1312             $settings->add(new admin_setting_configtext("auth_{$auth}/field_map_{$field}",
1313                     get_string('auth_fieldmapping', 'auth', $fieldname), '', '', PARAM_RAW, 30));
1314
1315             // Update local.
1316             $settings->add(new admin_setting_configselect("auth_{$auth}/field_updatelocal_{$field}",
1317                     get_string('auth_updatelocalfield', 'auth', $fieldname), '', 'oncreate', $updatelocaloptions));
1318
1319             // Update remote.
1320             if ($updateremotefields) {
1321                     $settings->add(new admin_setting_configselect("auth_{$auth}/field_updateremote_{$field}",
1322                         get_string('auth_updateremotefield', 'auth', $fieldname), '', 0, $updateextoptions));
1323             }
1324
1325             // Lock fields.
1326             $settings->add(new admin_setting_configselect("auth_{$auth}/field_lock_{$field}",
1327                     get_string('auth_fieldlockfield', 'auth', $fieldname), '', 'unlocked', $lockoptions));
1328
1329         } else {
1330             // Lock fields Only.
1331             $settings->add(new admin_setting_configselect("auth_{$auth}/field_lock_{$field}",
1332                     get_string('auth_fieldlockfield', 'auth', $fieldname), '', 'unlocked', $lockoptions));
1333         }
1334     }
1335 }