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 = array(
 106         'firstname',
 107         'lastname',
 108         'email',
 109         'city',
 110         'country',
 111         'lang',
 112         'description',
 113         'url',
 114         'idnumber',
 115         'institution',
 116         'department',
 117         'phone1',
 118         'phone2',
 119         'address',
 120         'firstnamephonetic',
 121         'lastnamephonetic',
 122         'middlename',
 123         'alternatename'
 124     );
 125
 126     /**
 127      * Moodle custom fields to sync with.
 128      * @var array()
 129      */
 130     var $customfields = null;
 131
 132     /**
 133      * This is the primary method that is used by the authenticate_user_login()
 134      * function in moodlelib.php.
 135      *
 136      * This method should return a boolean indicating
 137      * whether or not the username and password authenticate successfully.
 138      *
 139      * Returns true if the username and password work and false if they are
 140      * wrong or don't exist.
 141      *
 142      * @param string $username The username (with system magic quotes)
 143      * @param string $password The password (with system magic quotes)
 144      *
 145      * @return bool Authentication success or failure.
 146      */
 147     function user_login($username, $password) {
 148         print_error('mustbeoveride', 'debug', '', 'user_login()' );
 149     }
 150
 151     /**
 152      * Returns true if this authentication plugin can change the users'
 153      * password.
 154      *
 155      * @return bool
 156      */
 157     function can_change_password() {
 158         //override if needed
 159         return false;
 160     }
 161
 162     /**
 163      * Returns the URL for changing the users' passwords, or empty if the default
 164      * URL can be used.
 165      *
 166      * This method is used if can_change_password() returns true.
 167      * This method is called only when user is logged in, it may use global $USER.
 168      * If you are using a plugin config variable in this method, please make sure it is set before using it,
 169      * as this method can be called even if the plugin is disabled, in which case the config values won't be set.
 170      *
 171      * @return moodle_url url of the profile page or null if standard used
 172      */
 173     function change_password_url() {
 174         //override if needed
 175         return null;
 176     }
 177
 178     /**
 179      * Returns true if this authentication plugin can edit the users'
 180      * profile.
 181      *
 182      * @return bool
 183      */
 184     function can_edit_profile() {
 185         //override if needed
 186         return true;
 187     }
 188
 189     /**
 190      * Returns the URL for editing the users' profile, or empty if the default
 191      * URL can be used.
 192      *
 193      * This method is used if can_edit_profile() returns true.
 194      * This method is called only when user is logged in, it may use global $USER.
 195      *
 196      * @return moodle_url url of the profile page or null if standard used
 197      */
 198     function edit_profile_url() {
 199         //override if needed
 200         return null;
 201     }
 202
 203     /**
 204      * Returns true if this authentication plugin is "internal".
 205      *
 206      * Internal plugins use password hashes from Moodle user table for authentication.
 207      *
 208      * @return bool
 209      */
 210     function is_internal() {
 211         //override if needed
 212         return true;
 213     }
 214
 215     /**
 216      * Returns false if this plugin is enabled but not configured.
 217      *
 218      * @return bool
 219      */
 220     public function is_configured() {
 221         return false;
 222     }
 223
 224     /**
 225      * Indicates if password hashes should be stored in local moodle database.
 226      * @return bool true means md5 password hash stored in user table, false means flag 'not_cached' stored there instead
 227      */
 228     function prevent_local_passwords() {
 229         return !$this->is_internal();
 230     }
 231
 232     /**
 233      * Indicates if moodle should automatically update internal user
 234      * records with data from external sources using the information
 235      * from get_userinfo() method.
 236      *
 237      * @return bool true means automatically copy data from ext to user table
 238      */
 239     function is_synchronised_with_external() {
 240         return !$this->is_internal();
 241     }
 242
 243     /**
 244      * Updates the user's password.
 245      *
 246      * In previous versions of Moodle, the function
 247      * auth_user_update_password accepted a username as the first parameter. The
 248      * revised function expects a user object.
 249      *
 250      * @param  object  $user        User table object
 251      * @param  string  $newpassword Plaintext password
 252      *
 253      * @return bool                  True on success
 254      */
 255     function user_update_password($user, $newpassword) {
 256         //override if needed
 257         return true;
 258     }
 259
 260     /**
 261      * Called when the user record is updated.
 262      * Modifies user in external database. It takes olduser (before changes) and newuser (after changes)
 263      * compares information saved modified information to external db.
 264      *
 265      * @param mixed $olduser     Userobject before modifications    (without system magic quotes)
 266      * @param mixed $newuser     Userobject new modified userobject (without system magic quotes)
 267      * @return boolean true if updated or update ignored; false if error
 268      *
 269      */
 270     function user_update($olduser, $newuser) {
 271         //override if needed
 272         return true;
 273     }
 274
 275     /**
 276      * User delete requested - internal user record is mared as deleted already, username not present anymore.
 277      *
 278      * Do any action in external database.
 279      *
 280      * @param object $user       Userobject before delete    (without system magic quotes)
 281      * @return void
 282      */
 283     function user_delete($olduser) {
 284         //override if needed
 285         return;
 286     }
 287
 288     /**
 289      * Returns true if plugin allows resetting of internal password.
 290      *
 291      * @return bool
 292      */
 293     function can_reset_password() {
 294         //override if needed
 295         return false;
 296     }
 297
 298     /**
 299      * Returns true if plugin allows resetting of internal password.
 300      *
 301      * @return bool
 302      */
 303     function can_signup() {
 304         //override if needed
 305         return false;
 306     }
 307
 308     /**
 309      * Sign up a new user ready for confirmation.
 310      * Password is passed in plaintext.
 311      *
 312      * @param object $user new user object
 313      * @param boolean $notify print notice with link and terminate
 314      */
 315     function user_signup($user, $notify=true) {
 316         //override when can signup
 317         print_error('mustbeoveride', 'debug', '', 'user_signup()' );
 318     }
 319
 320     /**
 321      * Return a form to capture user details for account creation.
 322      * This is used in /login/signup.php.
 323      * @return moodle_form A form which edits a record from the user table.
 324      */
 325     function signup_form() {
 326         global $CFG;
 327
 328         require_once($CFG->dirroot.'/login/signup_form.php');
 329         return new login_signup_form(null, null, 'post', '', array('autocomplete'=>'on'));
 330     }
 331
 332     /**
 333      * Returns true if plugin allows confirming of new users.
 334      *
 335      * @return bool
 336      */
 337     function can_confirm() {
 338         //override if needed
 339         return false;
 340     }
 341
 342     /**
 343      * Confirm the new user as registered.
 344      *
 345      * @param string $username
 346      * @param string $confirmsecret
 347      */
 348     function user_confirm($username, $confirmsecret) {
 349         //override when can confirm
 350         print_error('mustbeoveride', 'debug', '', 'user_confirm()' );
 351     }
 352
 353     /**
 354      * Checks if user exists in external db
 355      *
 356      * @param string $username (with system magic quotes)
 357      * @return bool
 358      */
 359     function user_exists($username) {
 360         //override if needed
 361         return false;
 362     }
 363
 364     /**
 365      * return number of days to user password expires
 366      *
 367      * If userpassword does not expire it should return 0. If password is already expired
 368      * it should return negative value.
 369      *
 370      * @param mixed $username username (with system magic quotes)
 371      * @return integer
 372      */
 373     function password_expire($username) {
 374         return 0;
 375     }
 376     /**
 377      * Sync roles for this user - usually creator
 378      *
 379      * @param $user object user object (without system magic quotes)
 380      */
 381     function sync_roles($user) {
 382         //override if needed
 383     }
 384
 385     /**
 386      * Read user information from external database and returns it as array().
 387      * Function should return all information available. If you are saving
 388      * this information to moodle user-table you should honour synchronisation flags
 389      *
 390      * @param string $username username
 391      *
 392      * @return mixed array with no magic quotes or false on error
 393      */
 394     function get_userinfo($username) {
 395         //override if needed
 396         return array();
 397     }
 398
 399     /**
 400      * Prints a form for configuring this authentication plugin.
 401      *
 402      * This function is called from admin/auth.php, and outputs a full page with
 403      * a form for configuring this plugin.
 404      *
 405      * @param object $config
 406      * @param object $err
 407      * @param array $user_fields
 408      */
 409     function config_form($config, $err, $user_fields) {
 410         //override if needed
 411     }
 412
 413     /**
 414      * A chance to validate form data, and last chance to
 415      * do stuff before it is inserted in config_plugin
 416      * @param object object with submitted configuration settings (without system magic quotes)
 417      * @param array $err array of error messages
 418      */
 419      function validate_form($form, &$err) {
 420         //override if needed
 421     }
 422
 423     /**
 424      * Processes and stores configuration data for this authentication plugin.
 425      *
 426      * @param object object with submitted configuration settings (without system magic quotes)
 427      */
 428     function process_config($config) {
 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      * Post authentication hook.
 469      * This method is called from authenticate_user_login() for all enabled auth plugins.
 470      *
 471      * @param object $user user object, later used for $USER
 472      * @param string $username (with system magic quotes)
 473      * @param string $password plain text password (with system magic quotes)
 474      */
 475     function user_authenticated_hook(&$user, $username, $password) {
 476         //override if needed
 477     }
 478
 479     /**
 480      * Pre logout hook.
 481      * This method is called from require_logout() for all enabled auth plugins,
 482      *
 483      * @global object
 484      */
 485     function prelogout_hook() {
 486         global $USER; // use $USER->auth to find the plugin used for login
 487
 488         //override if needed
 489     }
 490
 491     /**
 492      * Hook for overriding behaviour of logout page.
 493      * This method is called from login/logout.php page for all enabled auth plugins.
 494      *
 495      * @global object
 496      * @global string
 497      */
 498     function logoutpage_hook() {
 499         global $USER;     // use $USER->auth to find the plugin used for login
 500         global $redirect; // can be used to override redirect after logout
 501
 502         //override if needed
 503     }
 504
 505     /**
 506      * Hook called before timing out of database session.
 507      * This is useful for SSO and MNET.
 508      *
 509      * @param object $user
 510      * @param string $sid session id
 511      * @param int $timecreated start of session
 512      * @param int $timemodified user last seen
 513      * @return bool true means do not timeout session yet
 514      */
 515     function ignore_timeout_hook($user, $sid, $timecreated, $timemodified) {
 516         return false;
 517     }
 518
 519     /**
 520      * Return the properly translated human-friendly title of this auth plugin
 521      *
 522      * @todo Document this function
 523      */
 524     function get_title() {
 525         return get_string('pluginname', "auth_{$this->authtype}");
 526     }
 527
 528     /**
 529      * Get the auth description (from core or own auth lang files)
 530      *
 531      * @return string The description
 532      */
 533     function get_description() {
 534         $authdescription = get_string("auth_{$this->authtype}description", "auth_{$this->authtype}");
 535         return $authdescription;
 536     }
 537
 538     /**
 539      * Returns whether or not the captcha element is enabled, and the admin settings fulfil its requirements.
 540      *
 541      * @abstract Implement in child classes
 542      * @return bool
 543      */
 544     function is_captcha_enabled() {
 545         return false;
 546     }
 547
 548     /**
 549      * Returns whether or not this authentication plugin can be manually set
 550      * for users, for example, when bulk uploading users.
 551      *
 552      * This should be overriden by authentication plugins where setting the
 553      * authentication method manually is allowed.
 554      *
 555      * @return bool
 556      * @since Moodle 2.6
 557      */
 558     function can_be_manually_set() {
 559         // Override if needed.
 560         return false;
 561     }
 562
 563     /**
 564      * Returns a list of potential IdPs that this authentication plugin supports.
 565      * This is used to provide links on the login page.
 566      *
 567      * @param string $wantsurl the relative url fragment the user wants to get to.  You can use this to compose a returnurl, for example
 568      *
 569      * @return array like:
 570      *              array(
 571      *                  array(
 572      *                      'url' => 'http://someurl',
 573      *                      'icon' => new pix_icon(...),
 574      *                      'name' => get_string('somename', 'auth_yourplugin'),
 575      *                 ),
 576      *             )
 577      */
 578     function loginpage_idp_list($wantsurl) {
 579         return array();
 580     }
 581
 582     /**
 583      * Return custom user profile fields.
 584      *
 585      * @return array list of custom fields.
 586      */
 587     public function get_custom_user_profile_fields() {
 588         global $DB;
 589         // If already retrieved then return.
 590         if (!is_null($this->customfields)) {
 591             return $this->customfields;
 592         }
 593
 594         $this->customfields = array();
 595         if ($proffields = $DB->get_records('user_info_field')) {
 596             foreach ($proffields as $proffield) {
 597                 $this->customfields[] = 'profile_field_'.$proffield->shortname;
 598             }
 599         }
 600         unset($proffields);
 601
 602         return $this->customfields;
 603     }
 604
 605     /**
 606      * Post logout hook.
 607      *
 608      * This method is used after moodle logout by auth classes to execute server logout.
 609      *
 610      * @param stdClass $user clone of USER object before the user session was terminated
 611      */
 612     public function postlogout_hook($user) {
 613     }
 614 }
 615
 616 /**
 617  * Verify if user is locked out.
 618  *
 619  * @param stdClass $user
 620  * @return bool true if user locked out
 621  */
 622 function login_is_lockedout($user) {
 623     global $CFG;
 624
 625     if ($user->mnethostid != $CFG->mnet_localhost_id) {
 626         return false;
 627     }
 628     if (isguestuser($user)) {
 629         return false;
 630     }
 631
 632     if (empty($CFG->lockoutthreshold)) {
 633         // Lockout not enabled.
 634         return false;
 635     }
 636
 637     if (get_user_preferences('login_lockout_ignored', 0, $user)) {
 638         // This preference may be used for accounts that must not be locked out.
 639         return false;
 640     }
 641
 642     $locked = get_user_preferences('login_lockout', 0, $user);
 643     if (!$locked) {
 644         return false;
 645     }
 646
 647     if (empty($CFG->lockoutduration)) {
 648         // Locked out forever.
 649         return true;
 650     }
 651
 652     if (time() - $locked < $CFG->lockoutduration) {
 653         return true;
 654     }
 655
 656     login_unlock_account($user);
 657
 658     return false;
 659 }
 660
 661 /**
 662  * To be called after valid user login.
 663  * @param stdClass $user
 664  */
 665 function login_attempt_valid($user) {
 666     global $CFG;
 667
 668     // Note: user_loggedin event is triggered in complete_user_login().
 669
 670     if ($user->mnethostid != $CFG->mnet_localhost_id) {
 671         return;
 672     }
 673     if (isguestuser($user)) {
 674         return;
 675     }
 676
 677     // Always unlock here, there might be some race conditions or leftovers when switching threshold.
 678     login_unlock_account($user);
 679 }
 680
 681 /**
 682  * To be called after failed user login.
 683  * @param stdClass $user
 684  */
 685 function login_attempt_failed($user) {
 686     global $CFG;
 687
 688     if ($user->mnethostid != $CFG->mnet_localhost_id) {
 689         return;
 690     }
 691     if (isguestuser($user)) {
 692         return;
 693     }
 694
 695     $count = get_user_preferences('login_failed_count', 0, $user);
 696     $last = get_user_preferences('login_failed_last', 0, $user);
 697     $sincescuccess = get_user_preferences('login_failed_count_since_success', $count, $user);
 698     $sincescuccess = $sincescuccess + 1;
 699     set_user_preference('login_failed_count_since_success', $sincescuccess, $user);
 700
 701     if (empty($CFG->lockoutthreshold)) {
 702         // No threshold means no lockout.
 703         // Always unlock here, there might be some race conditions or leftovers when switching threshold.
 704         login_unlock_account($user);
 705         return;
 706     }
 707
 708     if (!empty($CFG->lockoutwindow) and time() - $last > $CFG->lockoutwindow) {
 709         $count = 0;
 710     }
 711
 712     $count = $count+1;
 713
 714     set_user_preference('login_failed_count', $count, $user);
 715     set_user_preference('login_failed_last', time(), $user);
 716
 717     if ($count >= $CFG->lockoutthreshold) {
 718         login_lock_account($user);
 719     }
 720 }
 721
 722 /**
 723  * Lockout user and send notification email.
 724  *
 725  * @param stdClass $user
 726  */
 727 function login_lock_account($user) {
 728     global $CFG;
 729
 730     if ($user->mnethostid != $CFG->mnet_localhost_id) {
 731         return;
 732     }
 733     if (isguestuser($user)) {
 734         return;
 735     }
 736
 737     if (get_user_preferences('login_lockout_ignored', 0, $user)) {
 738         // This user can not be locked out.
 739         return;
 740     }
 741
 742     $alreadylockedout = get_user_preferences('login_lockout', 0, $user);
 743
 744     set_user_preference('login_lockout', time(), $user);
 745
 746     if ($alreadylockedout == 0) {
 747         $secret = random_string(15);
 748         set_user_preference('login_lockout_secret', $secret, $user);
 749
 750         $oldforcelang = force_current_language($user->lang);
 751
 752         $site = get_site();
 753         $supportuser = core_user::get_support_user();
 754
 755         $data = new stdClass();
 756         $data->firstname = $user->firstname;
 757         $data->lastname  = $user->lastname;
 758         $data->username  = $user->username;
 759         $data->sitename  = format_string($site->fullname);
 760         $data->link      = $CFG->wwwroot.'/login/unlock_account.php?u='.$user->id.'&s='.$secret;
 761         $data->admin     = generate_email_signoff();
 762
 763         $message = get_string('lockoutemailbody', 'admin', $data);
 764         $subject = get_string('lockoutemailsubject', 'admin', format_string($site->fullname));
 765
 766         if ($message) {
 767             // Directly email rather than using the messaging system to ensure its not routed to a popup or jabber.
 768             email_to_user($user, $supportuser, $subject, $message);
 769         }
 770
 771         force_current_language($oldforcelang);
 772     }
 773 }
 774
 775 /**
 776  * Unlock user account and reset timers.
 777  *
 778  * @param stdClass $user
 779  */
 780 function login_unlock_account($user) {
 781     unset_user_preference('login_lockout', $user);
 782     unset_user_preference('login_failed_count', $user);
 783     unset_user_preference('login_failed_last', $user);
 784
 785     // Note: do not clear the lockout secret because user might click on the link repeatedly.
 786 }