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