lib.php

<?php
/**
 *
 * @package    mahara
 * @subpackage auth
 * @author     Catalyst IT Ltd
 * @license    http://www.gnu.org/copyleft/gpl.html GNU GPL version 3 or later
 * @copyright  For copyright information on Mahara, please see the README file distributed with this software.
 *
 */

defined('INTERNAL') || die();

require('session.php');
require(get_config('docroot') . 'auth/user.php');
require_once(get_config('docroot') . '/lib/htmloutput.php');

/**
 * Unknown user exception
 */
class AuthUnknownUserException extends UserException {}

/**
 * An instance of an auth plugin failed during execution
 * e.g. LDAP auth failed to connect to a directory
 * Developers can use this to fail an individual auth
 * instance, but not kill all from being tried.
 * If appropriate - the 'message' of the exception will be used
 * as the display message, so don't forget to language translate it
 */
class AuthInstanceException extends UserException {

    public function strings() {
        return array_merge(parent::strings(),
                           array('title' => $this->get_sitename() . ': Authentication problem'));
    }
}

/**
 * We tried to call a method on an auth plugin that hasn't been init'ed
 * successfully
 */
class UninitialisedAuthException extends SystemException {}

/**
 * We tried creating automatically creating an account for a user but
 * it failed for a reason that the user might want to know about
 * (e.g. they used an email address that's already used on the site)
 */
class AccountAutoCreationException extends AuthInstanceException {

    public function strings() {
        return array_merge(parent::strings(),
                           array('message' => 'The automatic creation of your user account failed.'
                                 . "\nDetails if any, follow:"));
    }
}

/**
 * Base authentication class. Provides a common interface with which
 * authentication can be carried out for system users.
 *
 * @todo for authentication:
 *   - inactivity: each institution has inactivity timeout times, this needs
 *     to be supported
 *     - this means the lastlogin field needs to be updated on the usr table
 *     - warnings are handled by cron
 */
abstract class Auth {

    protected $instanceid;
    protected $institution;
    protected $instancename;
    protected $priority;
    protected $authname;
    protected $config;
    protected $has_instance_config;
    protected $type;
    protected $ready;

    /**
     * Given an id, create the auth object and retrieve the config settings
     * If an instance ID is provided, get all the *instance* config settings
     *
     * @param  int  $id   The unique ID of the auth instance
     * @return bool       Whether the create was successful
     */
    public function __construct($id = null) {
        $this->ready = false;
    }

    /**
     * Instantiate the plugin by pulling the config data for an instance from
     * the database
     *
     * @param  int  $id   The unique ID of the auth instance
     * @return bool       Whether the create was successful
     */
    public function init($id) {
        if (!is_numeric($id) || intval($id) != $id) {
            throw new UserNotFoundException();
        }

        $instance = get_record('auth_instance', 'id', $id);
        if (empty($instance)) {
            throw new UserNotFoundException();
        }

        $this->instanceid   = $id;
        $this->institution  = $instance->institution;
        $this->instancename = $instance->instancename;
        $this->priority     = $instance->priority;
        $this->authname     = $instance->authname;

        // Return now if the plugin type doesn't require any config
        // (e.g. internal)
        if ($this->has_instance_config == false) {
            return true;
        }

        $records = get_records_array('auth_instance_config', 'instance', $this->instanceid);

        if ($records == false) {
            return false;
        }

        foreach($records as $record) {
            $this->config[$record->field] = $record->value;
        }

        return true;
    }

    /**
     * The __get overloader is invoked when the requested member is private or
     * protected, or just doesn't exist.
     *
     * @param  string  $name   The name of the value to fetch
     * @return mixed           The value
     */
    public function __get($name) {
        $approved_members = array('instanceid', 'institution', 'instancename', 'priority', 'authname', 'type');

        if (in_array($name, $approved_members)) {
            return $this->{$name};
        }
        if (isset($this->config[$name])) {
            return $this->config[$name];
        }
        return null;
    }

    /**
     * The __set overloader is invoked when the specified member is private or
     * protected, or just doesn't exist.
     *
     * @param  string  $name   The name of the value to set
     * @param  mixed   $value  The value to assign
     * @return void
     */
    public function __set($name, $value) {
        /*
        if (property_exists($this, $name)) {
            $this->{$name} = $value;
            return;
        }
        */
        throw new SystemException('It\'s forbidden to set values on Auth objects');
    }

    /**
     * Check that the plugin has been initialised before we try to use it.
     *
     * @throws UninitialisedAuthException
     * @return bool
     */
    protected function must_be_ready() {
        if ($this->ready == false) {
            throw new UninitialisedAuthException('This Auth plugin has not been initialised');
        }
        return true;
    }

    /**
     * Fetch the URL that users can visit to change their passwords. This might
     * be a Moodle installation, for example.
     *
     * @return  mixed   URL to change password or false if there is none
     */
    public function changepasswordurl() {
        $this->must_be_ready();
        if (empty($this->config['changepasswordurl'])) {
            return false;
        }
        return $this->config['changepasswordurl'];
    }

    /**
     * Given a username and password, attempts to log the user in.
     *
     * @param object $user      An object with username member (at least)
     * @param string $password  The password to use for the attempt
     * @return bool             Whether the authentication was successful
     * @throws AuthUnknownUserException  If the user is unknown to the
     *                                   authentication method
     */
    public function authenticate_user_account($user, $password) {
        $this->must_be_ready();
        return false;
    }

    /**
     * Given a username, returns whether the user exists in the usr table
     *
     * @param string $username The username to attempt to identify
     * @return bool            Whether the username exists
     */
    public function user_exists($username) {
        $this->must_be_ready();
        if (record_exists_select('usr', 'LOWER(username) = ?', array(strtolower($username)))) {
            return true;
        }
        throw new AuthUnknownUserException("\"$username\" is not known to Auth");
    }

    /**
     * Returns whether the authentication instance can automatically create a
     * user record.
     *
     * Auto creating users means that the authentication plugin can say that
     * users who don't exist yet in Mahara's usr table are allowed, and Mahara
     * should create a user account for them. Example: the first time a user logs
     * in, when authenticating against an ldap store or similar).
     *
     * However, if a plugin says a user can be authenticated, then it must
     * implement the get_user_info() method which will be called to find out
     * information about the user so a record in the usr table _can_ be created
     * for the new user.
     *
     * Authentication methods must implement this method. Some may choose to
     * implement it by returning an instance config value that the admin user
     * can set.
     *
     * @return bool
     */
    public abstract function can_auto_create_users();

    /**
     * If this plugin allows new user's to self-register, this function will be
     * called to check whether it is okay to display a captcha method on the new
     * user self-registration form.
     */
    public static function can_use_registration_captcha() {
        return true;
    }

    /**
     * Given a username, returns a hash of information about a user from the
     * external data source.
     *
     * @param string $username The username to look up information for
     * @return array           The information for the user
     * @throws AuthUnknownUserException If the user is unknown to the
     *                                  authentication method
     */
    public function get_user_info($username) {
        return false;
    }

    /**
     * Given a password, returns whether it is in a valid format for this
     * authentication method.
     *
     * This only needs to be defined by subclasses if:
     *  - They implement the change_password method, which means that the
     *    system can use the <kbd>passwordchange</kbd> flag on the <kbd>usr</kbd>
     *    table to control whether the user's password needs changing.
     *  - The password that a user can set must be in a certain format.
     *
     * The default behaviour is to assume that the password is in a valid form,
     * so make sure to implement this method if this is not the case!
     *
     * This method is defined to be empty, so that authentication methods do
     * not have to specify a format if they do not need to.
     *
     * @param string $password The password to check
     * @return bool            Whether the username is in valid form.
     */
    public function is_password_valid($password) {
        return true;
    }

    /**
     * Called when a user is being logged in, after the main authentication routines.
     *
     * You can use $USER->login() to perform any additional tasks, for example
     * to set a cookie that another application can read, or pull some data
     * from somewhere.
     *
     * This method has no parameters and needs no return value
     */
    public function login() {
    }

    /**
     * Called when a user is being logged out, either by clicking a logout
     * link, their session timing out or some other method where their session
     * is explicitly being ended with no more processing to take place on this
     * page load.
     *
     * You can use $USER->logout() to log a user out but continue page
     * processing if necessary. register.php is an example of such a place
     * where this happens.
     *
     * If you define this hook, you can call $USER->logout() in it if you need
     * to before redirecting. Otherwise, it will be called for you once your
     * hook has run.
     *
     * If you do not explicitly redirect yourself, once this hook is finished
     * the user will be redirected to the homepage with a message saying they
     * have been logged out successfully.
     *
     * This method has no parameters and needs no return value
     */
    public function logout() {
    }

    /**
     * Indicates whether this auth instance is parent to another auth instance
     * @return boolean (For backwards-compatibility reasons, it actually returns $this or null)
     */
    public function is_parent_authority() {
        if (count_records('auth_instance_config', 'field', 'parent', 'value', $this->instanceid)) {
            return $this;
        }
        else {
            return null;
        }
    }

    /**
     * Returns the ID of this instance's parent authority; or FALSE if it has no parent authority
     * @return int|false
     */
    public function get_parent_authority() {
        return get_field('auth_instance_config', 'value', 'instance', $this->id, 'field', 'parent');
    }


    /**
     * Indicates whether or not this auth instance uses the remote username. Most auth instances
     * will only use it if they are the parent to another auth instance.
     */
    public function needs_remote_username() {
        return (boolean) $this->is_parent_authority();
    }
}


/******************************************************************************/
    // End of Auth base-class
/******************************************************************************/

/**
 * Handles authentication by setting up a session for a user if they are logged
 * in.
 *
 * This function combined with the Session class is smart - if the user is not
 * logged in then they do not get a session, which prevents simple curl hits
 * or search engine crawls to a page from getting sessions they won't use.
 *
 * Once the user has a session, they keep it even if the log out, so it can
 * be reused. The session does expire, but the expiry time is typically a week
 * or more.
 *
 * If the user is not authenticated for this page, then this function will
 * exit, printing the login page. Therefore, after including init.php, you can
 * be sure that the user is logged in, or has a valid guest key. However, no
 * testing is done to make sure the user has the required permissions to see
 * the page.
 *
 */
function auth_setup () {
    global $SESSION, $USER;

    // If the system is not installed, let the user through in the hope that
    // they can fix this little problem :)
    if (!get_config('installed')) {
        $USER->logout();
        return;
    }

    // Check the time that the session is set to log out. If the user does
    // not have a session, this time will be 0.
    $sessionlogouttime = $USER->get('logout_time');

    // Need to doublecheck that the User's sessionid still has a match the usr_session table
    // It can disappear if the current user has hacked the real user's account and the real user has
    // reset the password clearing the session from usr_session.
    $sessionexists = get_record('usr_session', 'usr', $USER->id, 'session', $USER->get('sessionid'));
    $parentuser = $USER->get('parentuser');
    if (($sessionlogouttime && isset($_GET['logout'])) || ($sessionexists === false && $USER->get('sessionid') != '' && empty($parentuser))) {
        // Call the authinstance' logout hook
        $authinstance = $SESSION->get('authinstance');
        if ($authinstance) {
            $authobj = AuthFactory::create($authinstance);
            $authobj->logout();
        }
        else {
            log_debug("Strange: user " . $USER->get('username') . " had no authinstance set in their session");
        }

        if (function_exists('local_logout')) {
            local_logout();
        }

        $USER->logout();
        $SESSION->add_ok_msg(get_string('loggedoutok'));
        redirect();
    }
    if ($sessionlogouttime > time()) {
        // The session is still active, so continue it.
        // Make sure that if a user's admin status has changed, they're kicked
        // out of the admin section
        if (in_admin_section()) {
            // Reload site admin/staff permissions
            $realuser = get_record('usr', 'id', $USER->id, null, null, null, null, 'admin,staff');
            if (!$USER->get('admin') && $realuser->admin) {
                // The user has been made into an admin
                $USER->admin = 1;
            }
            else if ($USER->get('admin') && !$realuser->admin) {
                // The user's admin rights have been taken away
                $USER->admin = 0;
            }
            if (!$USER->get('staff') && $realuser->staff) {
                $USER->staff = 1;
            }
            else if ($USER->get('staff') && !$realuser->staff) {
                $USER->staff = 0;
            }
            // Reload institutional admin/staff permissions
            $USER->reset_institutions();
            auth_check_admin_section();
        }
        $USER->renew();
        auth_check_required_fields();
    }
    else if ($sessionlogouttime > 0) {
        // The session timed out

        $authinstance = $SESSION->get('authinstance');
        if ($authinstance) {
            $authobj = AuthFactory::create($authinstance);

            $mnetuser = 0;
            if ($SESSION->get('mnetuser') && $authobj->parent) {
                // We wish to remember that the user is an MNET user - even though
                // they're using the local login form
                $mnetuser = $USER->get('id');
            }

            $authobj->logout();
            $USER->logout();

            if ($mnetuser != 0) {
                $SESSION->set('mnetuser', $mnetuser);
                $SESSION->set('authinstance', $authinstance);
            }
        }
        else {
            log_debug("Strange: user " . $USER->get('username') . " had no authinstance set in their session");
        }

        if (defined('JSON')) {
            json_reply('global', get_string('sessiontimedoutreload'), 1);
        }
        if (defined('IFRAME')) {
            header('Content-type: text/html');
            print_auth_frame();
            exit;
        }

        // If the page the user is viewing is public, inform them that they can
        // log in again
        if (defined('PUBLIC')) {
            // @todo this links to ?login - later it should do magic to make
            // sure that whatever GET string is made it includes the old data
            // correctly
            $loginurl = $_SERVER['REQUEST_URI'];
            $loginurl .= (false === strpos($loginurl, '?')) ? '?' : '&';
            $loginurl .= 'login';
            $SESSION->add_info_msg(get_string('sessiontimedoutpublic', 'mahara', hsc($loginurl)), false);
            return;
        }

        auth_draw_login_page(get_string('sessiontimedout'));
    }
    else {
        // There is no session, so we check to see if one needs to be started.
        // Build login form. If the form is submitted it will be handled here,
        // and set $USER for us (this will happen when users hit a page and
        // specify login data immediately
        require_once('pieforms/pieform.php');
        $form = new Pieform(auth_get_login_form());
        $SESSION->loginform = $form;
        if ($USER->is_logged_in()) {
            return;
        }

        // Check if the page is public or the site is configured to be public.
        if (defined('PUBLIC') && !isset($_GET['login'])) {
            if ($lang = param_alphanumext('lang', null)) {
                $SESSION->set('lang', $lang);
            }
            return;
        }

        // No session and a json request
        if (defined('JSON')) {
            json_reply('global', get_string('nosessionreload'), 1);
        }

        auth_draw_login_page(null, $form);
        exit;
    }
}

/**
 *
 * Returns all auth instances
 *
 * @return array                     Array of auth instance records
 */
function auth_get_auth_instances() {
    static $cache = array();

    if (count($cache) > 0) {
        return $cache;
    }

    $sql ='
        SELECT DISTINCT
            i.id,
            inst.name,
            inst.displayname,
            i.instancename,
            i.authname
        FROM
            {institution} inst,
            {auth_instance} i
        WHERE
            i.institution = inst.name
        ORDER BY
            inst.displayname,
            i.instancename';

    $cache = get_records_sql_array($sql, array());

    if (empty($cache)) {
        return array();
    }

    return $cache;
}


/**
 *
 * Given a list of institutions, returns all auth instances associated with them
 *
 * @return array                     Array of auth instance records
 */
function auth_get_auth_instances_for_institutions($institutions) {
    if (empty($institutions)) {
        return array();
    }
    $sql ='
        SELECT DISTINCT
            i.id,
            inst.name,
            inst.displayname,
            i.instancename,
            i.authname
        FROM
            {institution} inst,
            {auth_instance} i
        WHERE
            i.institution = inst.name AND
            inst.name IN (' . join(',', array_map('db_quote',$institutions)) . ')
        ORDER BY
            inst.displayname,
            i.instancename';

    return get_records_sql_array($sql, array());
}


/**
 * Given an institution, returns the authentication methods used by it, sorted
 * by priority.
 *
 * @param  string   $institution     Name of the institution
 * @return array                     Array of auth instance records
 */
function auth_get_auth_instances_for_institution($institution=null) {
    static $cache = array();

    if (null == $institution) {
        return array();
    }

    if (!isset($cache[$institution])) {
        // Get auth instances in order of priority
        // DO NOT CHANGE THE SORT ORDER OF THIS RESULT SET
        // YEAH EINSTEIN - THAT MEANS YOU!!!

        // TODO: work out why this won't accept a placeholder - had to use db_quote
        $sql ='
            SELECT DISTINCT
                i.id,
                i.instancename,
                i.priority,
                i.authname,
                a.requires_config,
                a.requires_parent
            FROM
                {auth_instance} i,
                {auth_installed} a
            WHERE
                a.name = i.authname AND
                i.institution = '. db_quote($institution).'
            ORDER BY
                i.priority,
                i.instancename';

        $cache[$institution] = get_records_sql_array($sql, array());

        if (empty($cache[$institution])) {
            return false;
        }
    }

    return $cache[$institution];
}

/**
 * Given a wwwroot, find any auth instances that can come from that host
 *
 * @param   string  wwwroot of the host that is connecting to us
 * @return  array   array of record objects
 */
function auth_get_auth_instances_for_wwwroot($wwwroot) {
    $query = "  SELECT
                    ai.id,
                    ai.authname,
                    i.id as institutionid,
                    i.displayname,
                    i.suspended
                FROM
                    {auth_instance} ai
                    INNER JOIN {institution} i
                        ON ai.institution = i.name
                    INNER JOIN {auth_instance_config} aic
                        ON aic.field = 'wwwroot'
                        AND aic.instance = ai.id
                WHERE
                    aic.value = ?";

    return get_records_sql_array($query, array('value' => $wwwroot));
}

/**
 * Given an institution, get all the auth types EXCEPT those that are already
 * enabled AND do not require configuration.
 *
 * @param  string   $institution     Name of the institution
 * @return array                     Array of auth instance records
 */
function auth_get_available_auth_types($institution=null) {

    if (!is_null($institution) && (!is_string($institution) || strlen($institution) > 255)) {
        return array();
    }

    // TODO: work out why this won't accept a placeholder - had to use db_quote
    $sql ='
        SELECT DISTINCT
            a.name,
            a.requires_config
        FROM
            {auth_installed} a
        LEFT JOIN
            {auth_instance} i
        ON
            a.name = i.authname AND
            i.institution = '. db_quote($institution).'
        WHERE
           (a.requires_config = 1 OR
            i.id IS NULL) AND
            a.active = 1
        ORDER BY
            a.name';

    if (is_null($institution)) {
        $result = get_records_array('auth_installed', '','','name','name, requires_config');
    } else {
        $result = get_records_sql_array($sql, array());
    }

    if (empty($result)) {
        return array();
    }

    foreach ($result as &$row) {
        $row->title       = get_string('title', 'auth.' . $row->name);
        safe_require('auth', $row->name);
        if ($row->is_usable = call_static_method('PluginAuth' . $row->name, 'is_usable')) {
            $row->description = get_string('description', 'auth.' . $row->name);
        }
        else {
            $row->description = get_string('notusable', 'auth.' . $row->name);
        }
    }
    usort($result, create_function('$a, $b', 'if ($a->is_usable != $b->is_usable) return $b->is_usable; return strnatcasecmp($a->title, $b->title);'));

    return $result;
}
/**
 * Checks that all the required fields are set, and handles setting them if required.
 *
 * Checks whether the current user needs to change their password, and handles
 * the password changing if it's required.
 */
function auth_check_required_fields() {
    global $USER, $SESSION;

    if (defined('NOCHECKREQUIREDFIELDS')) {
        return;
    }

    $changepassword = true;
    $elements = array();

    if (
        !$USER->get('passwordchange')                                // User doesn't need to change their password
        || ($USER->get('parentuser') && $USER->get('loginanyway'))   // User is masquerading and wants to log in anyway
        || defined('NOCHECKPASSWORDCHANGE')                          // The page wants to skip this hassle
        ) {
        $changepassword = false;
    }

    // Check if the user wants to log in anyway
    if ($USER->get('passwordchange') && $USER->get('parentuser') && isset($_GET['loginanyway'])) {
        $USER->loginanyway = true;
        $changepassword = false;
    }

    // Do not force password change on JSON request.
    if (defined('JSON') && JSON == true) {
        $changepassword = false;
    }

    if ($changepassword) {
        $authobj = AuthFactory::create($USER->authinstance);

        if ($authobj->changepasswordurl) {
            redirect($authobj->changepasswordurl);
            exit;
        }

        if (method_exists($authobj, 'change_password')) {

            if ($SESSION->get('resetusername')) {
                $elements['username'] = array(
                    'type' => 'text',
                    'defaultvalue' => $USER->get('username'),
                    'title' => get_string('changeusername', 'account'),
                    'description' => get_string('changeusernamedesc', 'account', hsc(get_config('sitename'))),
                );
            }

            $elements['password1'] = array(
                'type'        => 'password',
                'title'       => get_string('newpassword') . ':',
                'description' => get_string('yournewpassword'),
                'rules'       => array(
                    'required' => true
                )
            );

            $elements['password2'] = array(
                'type'        => 'password',
                'title'       => get_string('confirmpassword') . ':',
                'description' => get_string('yournewpasswordagain'),
                'rules'       => array(
                    'required' => true,
                ),
            );

            $elements['email'] = array(
                'type'   => 'text',
                'title'  => get_string('principalemailaddress', 'artefact.internal'),
                'ignore' => (trim($USER->get('email')) != '' && !preg_match('/@example\.org$/', $USER->get('email'))),
                'rules'  => array(
                    'required' => true,
                    'email'    => true,
                ),
            );
        }
    }
    else if (defined('JSON')) {
        // Don't need to check this for json requests
        return;
    }

    safe_require('artefact', 'internal');
    require_once('pieforms/pieform.php');

    $alwaysmandatoryfields = array_keys(ArtefactTypeProfile::get_always_mandatory_fields());
    foreach(ArtefactTypeProfile::get_mandatory_fields() as $field => $type) {
        // Always mandatory fields are stored in the usr table, so are part of
        // the user session object. We can save a query by grabbing them from
        // the session.
        if (in_array($field, $alwaysmandatoryfields) && $USER->get($field) != null) {
            continue;
        }
        // Not cached? Get value the standard way.
        if (get_profile_field($USER->get('id'), $field) != null) {
            continue;
        }

        if ($field == 'email') {
            if (isset($elements['email'])) {
                continue;
            }
            // Use a text field for their first e-mail address, not the
            // emaillist element
            $type = 'text';
        }

        $elements[$field] = array(
            'type'  => $type,
            'title' => get_string($field, 'artefact.internal'),
            'rules' => array('required' => true)
        );

        if ($field == 'socialprofile') {
            $elements[$field] = ArtefactTypeSocialprofile::get_new_profile_elements();
            // add an element to flag that socialprofile is in the list of fields.
            $elements['socialprofile_hidden'] = array(
                'type'  => 'hidden',
                'value' => 1,
            );
        }

        // @todo ruthlessly stolen from artefact/internal/index.php, could be merged
        if ($type == 'wysiwyg') {
            $elements[$field]['rows'] = 10;
            $elements[$field]['cols'] = 60;
        }
        if ($type == 'textarea') {
            $elements[$field]['rows'] = 4;
            $elements[$field]['cols'] = 60;
        }
        if ($field == 'country') {
            $elements[$field]['options'] = getoptions_country();
            $elements[$field]['defaultvalue'] = get_config('country');
        }

        if ($field == 'email') {
            // Check if a validation email has been sent
            if (record_exists('artefact_internal_profile_email', 'owner', $USER->get('id'))) {
                $elements['email']['type'] = 'html';
                $elements['email']['value'] = get_string('validationprimaryemailsent', 'auth');
                $elements['email']['disabled'] = true;
                $elements['email']['rules'] = array('required' => false);
            }
            else {
                $elements[$field]['rules']['email'] = true;
                $elements[$field]['description'] = get_string('primaryemaildescription', 'auth');
            }
        }
    }

    if (empty($elements)) { // No mandatory fields that aren't set
        return;
    }

    if ((count($elements) == 1) && isset($elements['email']) && ($elements['email']['type'] == 'html')) {
        // Display a message if there is only 1 required field and this field is email whose validation has been sent
        $elements['submit'] = array(
                'type' => 'submit',
                'value' => get_string('continue', 'admin')
        );
        $form = pieform(array(
                'name'     => 'requiredfields',
                'method'   => 'post',
                'action'   => get_config('wwwroot') . '?logout',
                'elements' => $elements
        ));
    }
    else {
        $elements['submit'] = array(
            'type' => 'submit',
            'value' => get_string('submit')
        );

        $form = pieform(array(
            'name'     => 'requiredfields',
            'method'   => 'post',
            'action'   => '',
            'elements' => $elements,
            'dieaftersubmit' => FALSE,
            'backoutaftersubmit' => TRUE,
        ));
    }

    // Has the form been successfully submitted? Back out and let the requested URL continue.
    if ($form === FALSE) {
        return;
    }

    $smarty = smarty();
    if ($USER->get('parentuser')) {
        $smarty->assign('loginasoverridepasswordchange',
            get_string('loginasoverridepasswordchange', 'admin',
                       '<a class="btn" href="' . get_config('wwwroot') . '?loginanyway">', '</a>'));
    }
    $smarty->assign('changepassword', $changepassword);
    $smarty->assign('changeusername', $SESSION->get('resetusername'));
    $smarty->assign('form', $form);
    $smarty->display('requiredfields.tpl');
    exit;
}

function requiredfields_validate(Pieform $form, $values) {
    global $USER;
    if (isset($values['password1'])) {

        // Get the authentication type for the user, and
        // use the information to validate the password
        $authobj = AuthFactory::create($USER->authinstance);

        // @todo this could be done by a custom form rule... 'password' => $user
        password_validate($form, $values, $USER);

        // The password cannot be the same as the old one
        try {
            if (!$form->get_error('password1')
                && $authobj->authenticate_user_account($USER, $values['password1'])) {
                $form->set_error('password1', get_string('passwordnotchanged'));
            }
        }
        // propagate error up as the collective error AuthUnknownUserException
         catch  (AuthInstanceException $e) {
            $form->set_error('password1', $e->getMessage());
        }

        if ($authobj->authname == 'internal' && isset($values['username']) && $values['username'] != $USER->get('username')) {
            if (!AuthInternal::is_username_valid($values['username'])) {
                $form->set_error('username', get_string('usernameinvalidform', 'auth.internal'));
            }
            if (!$form->get_error('username') && record_exists_select('usr', 'LOWER(username) = ?', array(strtolower($values['username'])))) {
                $form->set_error('username', get_string('usernamealreadytaken', 'auth.internal'));
            }
        }
    }
    // Check if email has been taken
    if (isset($values['email']) && record_exists('artefact_internal_profile_email', 'email', $values['email'])) {
            $form->set_error('email', get_string('unvalidatedemailalreadytaken', 'artefact.internal'));
    }
    // Check if the socialprofile url is valid.
    if (isset($values['socialprofile_hidden']) && $values['socialprofile_hidden'] && $values['socialprofile_profiletype'] == 'webpage' && !filter_var($values['socialprofile_profileurl'], FILTER_VALIDATE_URL)) {
        $form->set_error('socialprofile_profileurl', get_string('notvalidprofileurl', 'artefact.internal'));
    }
}

function requiredfields_submit(Pieform $form, $values) {
    global $USER, $SESSION;

    if (isset($values['password1'])) {
        $authobj = AuthFactory::create($USER->authinstance);

        // This method should exist, because if it did not then the change
        // password form would not have been shown.
        if ($password = $authobj->change_password($USER, $values['password1'])) {
            $SESSION->add_ok_msg(get_string('passwordsaved'));
        }
        else {
            throw new SystemException('Attempt by "' . $USER->get('username') . '@'
                . $USER->get('institution') . 'to change their password failed');
        }
    }

    if (isset($values['username'])) {
        $SESSION->set('resetusername', false);
        if ($values['username'] != $USER->get('username')) {
            $USER->username = $values['username'];
            $USER->commit();
            $otherfield = true;
        }
    }

    if (isset($values['socialprofile_hidden']) && $values['socialprofile_hidden']) {
        // Socialprofile fields. Save them on their own as they are a fieldset.
        set_profile_field($USER->get('id'), 'socialprofile', $values);
        $otherfield = true;
    }

    foreach ($values as $field => $value) {
        if (in_array($field, array('submit', 'sesskey', 'password1', 'password2', 'username',
                                   'socialprofile_service', 'socialprofile_profiletype',
                                   'socialprofile_profileurl', 'socialprofile_hidden'))) {
            continue;
        }
        if ($field == 'email') {
            $email = $values['email'];
            // Need to update the admin email on installation
            if ($USER->get('admin')) {
                $oldemail = get_field('usr', 'email', 'id', $USER->get('id'));
                if ($oldemail == 'admin@example.org') {
                    // we are dealing with the dummy email that is set on install
                    update_record('usr', array('email' => $email), array('id' => $USER->get('id')));
                    update_record('artefact_internal_profile_email', array('email' => $email), array('owner' => $USER->get('id')));
                    update_record('artefact', array('title' => $email), array('owner' => $USER->get('id'), 'artefacttype' => 'email'));
                }
            }
            // Check if a validation email has been sent, if not send one
            if (!record_exists('artefact_internal_profile_email', 'owner', $USER->get('id'))) {
                $key = get_random_key();
                $key_url = get_config('wwwroot') . 'artefact/internal/validate.php?email=' . rawurlencode($email) . '&key=' . $key;
                $key_url_decline = $key_url . '&decline=1';

                try {
                    $sitename = get_config('sitename');
                    email_user(
                        (object)array(
                            'id'            => $USER->get('id'),
                            'username'      => $USER->get('username'),
                            'firstname'     => $USER->get('firstname'),
                            'lastname'      => $USER->get('lastname'),
                            'preferredname' => $USER->get('preferredname'),
                            'admin'         => $USER->get('admin'),
                            'staff'         => $USER->get('staff'),
                            'email'         => $email,
                        ),
                        null,
                        get_string('emailvalidation_subject', 'artefact.internal'),
                        get_string('emailvalidation_body1', 'artefact.internal', $USER->get('firstname'), $email, $sitename, $key_url, $sitename, $key_url_decline)
                    );
                }
                catch (EmailException $e) {
                    $SESSION->add_error_msg($email);
                }

                insert_record(
                    'artefact_internal_profile_email',
                    (object) array(
                        'owner'    => $USER->get('id'),
                        'email'    => $email,
                        'verified' => 0,
                        'principal' => 1,
                        'key'      => $key,
                        'expiry'   => db_format_timestamp(time() + 86400),
                    )
                );
                $SESSION->add_ok_msg(get_string('validationemailsent', 'artefact.internal'));
            }
        }
        else {
            set_profile_field($USER->get('id'), $field, $value);
            $otherfield = true;
        }
    }

    if (isset($otherfield)) {
        $SESSION->add_ok_msg(get_string('requiredfieldsset', 'auth'));
    }

    // Update the title of user's first blog if first and/or last name have been changed
    $updatedfields = array_keys($values);
    if (in_array('firstname', $updatedfields) || in_array('lastname', $updatedfields)) {
        safe_require('artefact', 'blog');
        $userblogs = get_records_select_array('artefact', 'artefacttype = \'blog\' AND owner = ?', array($USER->get('id')));
        if ($userblogs && count($userblogs) == 1) {
            $defaultblog = new ArtefactTypeBlog($userblogs[0]->id);
            $defaultblog->set('title', get_string('defaultblogtitle', 'artefact.blog', display_name($USER, null, true)));
            $defaultblog->commit();
        }
    }

    if ($form->get_property('backoutaftersubmit')) {
        return;
    }

    redirect();
}

/**
 * Creates and displays the transient login page.
 *
 * This login page remembers all GET/POST data and passes it on. This way,
 * users can have their sessions time out, and then can log in again without
 * losing any of their data.
 *
 * As this function builds and validates a login form, it is possible that
 * calling this may validate a user to be logged in.
 *
 * @param Pieform $form If specified, just build this form to get the HTML
 *                      required. Otherwise, this function will build and
 *                      validate the form itself.
 * @access private
 */
function auth_draw_login_page($message=null, Pieform $form=null) {
    global $USER, $SESSION;
    if ($form != null) {
        $loginform = get_login_form_js($form->build());
    }
    else {
        require_once('pieforms/pieform.php');
        $loginform = get_login_form_js(pieform(auth_get_login_form()));
        /*
         * If $USER is set, the form was submitted even before being built.
         * This happens when a user's session times out and they resend post
         * data. The request should just continue if so.
         */
        if ($USER->is_logged_in()) {
            return;
        }

    }

    $externallogin = get_config('externallogin');
    if ($externallogin) {
        $externallogin = preg_replace('/{shorturlencoded}/', urlencode(get_relative_script_path()), $externallogin);
        $externallogin = preg_replace('/{wwwroot}/', get_config('wwwroot'), $externallogin);
        redirect($externallogin);
    }

    if ($message) {
        $SESSION->add_info_msg($message);
    }
    $smarty = smarty(array(), array(), array(), array('pagehelp' => false, 'sidebars' => false));
    $smarty->assign('login_form', $loginform);
    $smarty->assign('PAGEHEADING', get_string('loginto', 'mahara', get_config('sitename')));
    $smarty->assign('LOGINPAGE', true);
    $smarty->display('login.tpl');
    exit;
}

/**
 * Returns the definition of the login form, for display on the transient login page.
 *
 * @return array   The login form definition array.
 * @access private
 */
function auth_get_login_form() {
    $elements = auth_get_login_form_elements();

    $elements['login']['elements']['login_submitted'] = array(
        'type'  => 'hidden',
        'value' => 1
    );

    // Change login redirection for clean urls
    $url = get_relative_script_path();
    $getstart = strrpos($url, '?');
    if ($getstart !== false) {
        $getpart = substr($url, $getstart + 1);
        $url = substr($url, 0, $getstart);
    }
    if (!file_exists(get_config('docroot') . $url)) {
        // clean url, treat get string differently
        $get = array();
        if (isset($getpart)) {
            $getarr = explode('&', $getpart);
            if ($getarr) {
                foreach ($getarr as $data) {
                    $arr = explode('=', $data);
                    $get[$arr[0]] = isset($arr[1]) ? $arr[1] : null;
                }
            }
        }
    }
    else {
        $get = $_GET;
    }
    // The login page is completely transient, and it is smart because it
    // remembers the GET and POST data sent to it and resends that on
    // afterwards.
    $action = '';
    if ($get) {
        if (isset($get['logout'])) {
            // You can log the user out on any particular page by appending
            // ?logout to the URL. In this case, we don't want the "action"
            // of the url to include that, or be blank, else the next time
            // the user logs in they will be logged out again.
            $action = hsc(substr($_SERVER['REQUEST_URI'], 0, strpos($_SERVER['REQUEST_URI'], '?')));
        }
        else {
            $action .= '?';
            foreach ($get as $key => $value) {
                if ($key != 'login') {
                    $action .= hsc($key) . '=' . hsc($value) . '&';
                }
            }
            $action = substr($action, 0, -1);
        }
    }
    if ($_POST) {
        foreach ($_POST as $key => $value) {
            if (!isset($elements[$key]) && !isset($elements['login']['elements'][$key])) {
                $elements[$key] = array(
                    'type'  => 'hidden',
                    'value' => $value
                );
            }
        }
    }