mirror of
https://github.com/moodle/moodle.git
synced 2025-06-03 06:35:57 +02:00
57996fe956
For pages where there will be significant user interaction in which the server is not updated, it may be necessary to poll the server periodically to touch the session. This makes use of the existing checknet script which was designed for checking network connectivity but fits into this use-case reasonably well.
888 lines
31 KiB
PHP
888 lines
31 KiB
PHP
<?php
|
|
// This file is part of Moodle - http://moodle.org/
|
|
//
|
|
// Moodle is free software: you can redistribute it and/or modify
|
|
// it under the terms of the GNU General Public License as published by
|
|
// the Free Software Foundation, either version 3 of the License, or
|
|
// (at your option) any later version.
|
|
//
|
|
// Moodle is distributed in the hope that it will be useful,
|
|
// but WITHOUT ANY WARRANTY; without even the implied warranty of
|
|
// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
|
|
// GNU General Public License for more details.
|
|
//
|
|
// You should have received a copy of the GNU General Public License
|
|
// along with Moodle. If not, see <http://www.gnu.org/licenses/>.
|
|
|
|
/**
|
|
* Session manager class.
|
|
*
|
|
* @package core
|
|
* @copyright 2013 Petr Skoda {@link http://skodak.org}
|
|
* @license http://www.gnu.org/copyleft/gpl.html GNU GPL v3 or later
|
|
*/
|
|
|
|
namespace core\session;
|
|
|
|
defined('MOODLE_INTERNAL') || die();
|
|
|
|
/**
|
|
* Session manager, this is the public Moodle API for sessions.
|
|
*
|
|
* Following PHP functions MUST NOT be used directly:
|
|
* - session_start() - not necessary, lib/setup.php starts session automatically,
|
|
* use define('NO_MOODLE_COOKIE', true) if session not necessary.
|
|
* - session_write_close() - use \core\session\manager::write_close() instead.
|
|
* - session_destroy() - use require_logout() instead.
|
|
*
|
|
* @package core
|
|
* @copyright 2013 Petr Skoda {@link http://skodak.org}
|
|
* @license http://www.gnu.org/copyleft/gpl.html GNU GPL v3 or later
|
|
*/
|
|
class manager {
|
|
/** @var handler $handler active session handler instance */
|
|
protected static $handler;
|
|
|
|
/** @var bool $sessionactive Is the session active? */
|
|
protected static $sessionactive = null;
|
|
|
|
/**
|
|
* Start user session.
|
|
*
|
|
* Note: This is intended to be called only from lib/setup.php!
|
|
*/
|
|
public static function start() {
|
|
global $CFG, $DB;
|
|
|
|
if (isset(self::$sessionactive)) {
|
|
debugging('Session was already started!', DEBUG_DEVELOPER);
|
|
return;
|
|
}
|
|
|
|
self::load_handler();
|
|
|
|
// Init the session handler only if everything initialised properly in lib/setup.php file
|
|
// and the session is actually required.
|
|
if (empty($DB) or empty($CFG->version) or !defined('NO_MOODLE_COOKIES') or NO_MOODLE_COOKIES or CLI_SCRIPT) {
|
|
self::$sessionactive = false;
|
|
self::init_empty_session();
|
|
return;
|
|
}
|
|
|
|
try {
|
|
self::$handler->init();
|
|
self::prepare_cookies();
|
|
$newsid = empty($_COOKIE[session_name()]);
|
|
|
|
self::$handler->start();
|
|
|
|
self::initialise_user_session($newsid);
|
|
self::check_security();
|
|
|
|
// Link global $USER and $SESSION,
|
|
// this is tricky because PHP does not allow references to references
|
|
// and global keyword uses internally once reference to the $GLOBALS array.
|
|
// The solution is to use the $GLOBALS['USER'] and $GLOBALS['$SESSION']
|
|
// as the main storage of data and put references to $_SESSION.
|
|
$GLOBALS['USER'] = $_SESSION['USER'];
|
|
$_SESSION['USER'] =& $GLOBALS['USER'];
|
|
$GLOBALS['SESSION'] = $_SESSION['SESSION'];
|
|
$_SESSION['SESSION'] =& $GLOBALS['SESSION'];
|
|
|
|
} catch (\Exception $ex) {
|
|
@session_write_close();
|
|
self::init_empty_session();
|
|
self::$sessionactive = false;
|
|
throw $ex;
|
|
}
|
|
|
|
self::$sessionactive = true;
|
|
}
|
|
|
|
/**
|
|
* Returns current page performance info.
|
|
*
|
|
* @return array perf info
|
|
*/
|
|
public static function get_performance_info() {
|
|
if (!session_id()) {
|
|
return array();
|
|
}
|
|
|
|
self::load_handler();
|
|
$size = display_size(strlen(session_encode()));
|
|
$handler = get_class(self::$handler);
|
|
|
|
$info = array();
|
|
$info['size'] = $size;
|
|
$info['html'] = "<span class=\"sessionsize\">Session ($handler): $size</span> ";
|
|
$info['txt'] = "Session ($handler): $size ";
|
|
|
|
return $info;
|
|
}
|
|
|
|
/**
|
|
* Create handler instance.
|
|
*/
|
|
protected static function load_handler() {
|
|
global $CFG, $DB;
|
|
|
|
if (self::$handler) {
|
|
return;
|
|
}
|
|
|
|
// Find out which handler to use.
|
|
if (PHPUNIT_TEST) {
|
|
$class = '\core\session\file';
|
|
|
|
} else if (!empty($CFG->session_handler_class)) {
|
|
$class = $CFG->session_handler_class;
|
|
|
|
} else if (!empty($CFG->dbsessions) and $DB->session_lock_supported()) {
|
|
$class = '\core\session\database';
|
|
|
|
} else {
|
|
$class = '\core\session\file';
|
|
}
|
|
self::$handler = new $class();
|
|
}
|
|
|
|
/**
|
|
* Empty current session, fill it with not-logged-in user info.
|
|
*
|
|
* This is intended for installation scripts, unit tests and other
|
|
* special areas. Do NOT use for logout and session termination
|
|
* in normal requests!
|
|
*/
|
|
public static function init_empty_session() {
|
|
global $CFG;
|
|
|
|
$GLOBALS['SESSION'] = new \stdClass();
|
|
|
|
$GLOBALS['USER'] = new \stdClass();
|
|
$GLOBALS['USER']->id = 0;
|
|
if (isset($CFG->mnet_localhost_id)) {
|
|
$GLOBALS['USER']->mnethostid = $CFG->mnet_localhost_id;
|
|
} else {
|
|
// Not installed yet, the future host id will be most probably 1.
|
|
$GLOBALS['USER']->mnethostid = 1;
|
|
}
|
|
|
|
// Link global $USER and $SESSION.
|
|
$_SESSION = array();
|
|
$_SESSION['USER'] =& $GLOBALS['USER'];
|
|
$_SESSION['SESSION'] =& $GLOBALS['SESSION'];
|
|
}
|
|
|
|
/**
|
|
* Make sure all cookie and session related stuff is configured properly before session start.
|
|
*/
|
|
protected static function prepare_cookies() {
|
|
global $CFG;
|
|
|
|
if (!isset($CFG->cookiesecure) or (!is_https() and empty($CFG->sslproxy))) {
|
|
$CFG->cookiesecure = 0;
|
|
}
|
|
|
|
if (!isset($CFG->cookiehttponly)) {
|
|
$CFG->cookiehttponly = 0;
|
|
}
|
|
|
|
// Set sessioncookie variable if it isn't already.
|
|
if (!isset($CFG->sessioncookie)) {
|
|
$CFG->sessioncookie = '';
|
|
}
|
|
$sessionname = 'MoodleSession'.$CFG->sessioncookie;
|
|
|
|
// Make sure cookie domain makes sense for this wwwroot.
|
|
if (!isset($CFG->sessioncookiedomain)) {
|
|
$CFG->sessioncookiedomain = '';
|
|
} else if ($CFG->sessioncookiedomain !== '') {
|
|
$host = parse_url($CFG->wwwroot, PHP_URL_HOST);
|
|
if ($CFG->sessioncookiedomain !== $host) {
|
|
if (substr($CFG->sessioncookiedomain, 0, 1) === '.') {
|
|
if (!preg_match('|^.*'.preg_quote($CFG->sessioncookiedomain, '|').'$|', $host)) {
|
|
// Invalid domain - it must be end part of host.
|
|
$CFG->sessioncookiedomain = '';
|
|
}
|
|
} else {
|
|
if (!preg_match('|^.*\.'.preg_quote($CFG->sessioncookiedomain, '|').'$|', $host)) {
|
|
// Invalid domain - it must be end part of host.
|
|
$CFG->sessioncookiedomain = '';
|
|
}
|
|
}
|
|
}
|
|
}
|
|
|
|
// Make sure the cookiepath is valid for this wwwroot or autodetect if not specified.
|
|
if (!isset($CFG->sessioncookiepath)) {
|
|
$CFG->sessioncookiepath = '';
|
|
}
|
|
if ($CFG->sessioncookiepath !== '/') {
|
|
$path = parse_url($CFG->wwwroot, PHP_URL_PATH).'/';
|
|
if ($CFG->sessioncookiepath === '') {
|
|
$CFG->sessioncookiepath = $path;
|
|
} else {
|
|
if (strpos($path, $CFG->sessioncookiepath) !== 0 or substr($CFG->sessioncookiepath, -1) !== '/') {
|
|
$CFG->sessioncookiepath = $path;
|
|
}
|
|
}
|
|
}
|
|
|
|
// Discard session ID from POST, GET and globals to tighten security,
|
|
// this is session fixation prevention.
|
|
unset($GLOBALS[$sessionname]);
|
|
unset($_GET[$sessionname]);
|
|
unset($_POST[$sessionname]);
|
|
unset($_REQUEST[$sessionname]);
|
|
|
|
// Compatibility hack for non-browser access to our web interface.
|
|
if (!empty($_COOKIE[$sessionname]) && $_COOKIE[$sessionname] == "deleted") {
|
|
unset($_COOKIE[$sessionname]);
|
|
}
|
|
|
|
// Set configuration.
|
|
session_name($sessionname);
|
|
session_set_cookie_params(0, $CFG->sessioncookiepath, $CFG->sessioncookiedomain, $CFG->cookiesecure, $CFG->cookiehttponly);
|
|
ini_set('session.use_trans_sid', '0');
|
|
ini_set('session.use_only_cookies', '1');
|
|
ini_set('session.hash_function', '0'); // For now MD5 - we do not have room for sha-1 in sessions table.
|
|
ini_set('session.use_strict_mode', '0'); // We have custom protection in session init.
|
|
ini_set('session.serialize_handler', 'php'); // We can move to 'php_serialize' after we require PHP 5.5.4 form Moodle.
|
|
|
|
// Moodle does normal session timeouts, this is for leftovers only.
|
|
ini_set('session.gc_probability', 1);
|
|
ini_set('session.gc_divisor', 1000);
|
|
ini_set('session.gc_maxlifetime', 60*60*24*4);
|
|
}
|
|
|
|
/**
|
|
* Initialise $_SESSION, handles google access
|
|
* and sets up not-logged-in user properly.
|
|
*
|
|
* WARNING: $USER and $SESSION are set up later, do not use them yet!
|
|
*
|
|
* @param bool $newsid is this a new session in first http request?
|
|
*/
|
|
protected static function initialise_user_session($newsid) {
|
|
global $CFG, $DB;
|
|
|
|
$sid = session_id();
|
|
if (!$sid) {
|
|
// No session, very weird.
|
|
error_log('Missing session ID, session not started!');
|
|
self::init_empty_session();
|
|
return;
|
|
}
|
|
|
|
if (!$record = $DB->get_record('sessions', array('sid'=>$sid), 'id, sid, state, userid, lastip, timecreated, timemodified')) {
|
|
if (!$newsid) {
|
|
if (!empty($_SESSION['USER']->id)) {
|
|
// This should not happen, just log it, we MUST not produce any output here!
|
|
error_log("Cannot find session record $sid for user ".$_SESSION['USER']->id.", creating new session.");
|
|
}
|
|
// Prevent session fixation attacks.
|
|
session_regenerate_id(true);
|
|
}
|
|
$_SESSION = array();
|
|
}
|
|
unset($sid);
|
|
|
|
if (isset($_SESSION['USER']->id)) {
|
|
if (!empty($_SESSION['USER']->realuser)) {
|
|
$userid = $_SESSION['USER']->realuser;
|
|
} else {
|
|
$userid = $_SESSION['USER']->id;
|
|
}
|
|
|
|
// Verify timeout first.
|
|
$maxlifetime = $CFG->sessiontimeout;
|
|
$timeout = false;
|
|
if (isguestuser($userid) or empty($userid)) {
|
|
// Ignore guest and not-logged in timeouts, there is very little risk here.
|
|
$timeout = false;
|
|
|
|
} else if ($record->timemodified < time() - $maxlifetime) {
|
|
$timeout = true;
|
|
$authsequence = get_enabled_auth_plugins(); // Auths, in sequence.
|
|
foreach ($authsequence as $authname) {
|
|
$authplugin = get_auth_plugin($authname);
|
|
if ($authplugin->ignore_timeout_hook($_SESSION['USER'], $record->sid, $record->timecreated, $record->timemodified)) {
|
|
$timeout = false;
|
|
break;
|
|
}
|
|
}
|
|
}
|
|
|
|
if ($timeout) {
|
|
session_regenerate_id(true);
|
|
$_SESSION = array();
|
|
$DB->delete_records('sessions', array('id'=>$record->id));
|
|
|
|
} else {
|
|
// Update session tracking record.
|
|
|
|
$update = new \stdClass();
|
|
$updated = false;
|
|
|
|
if ($record->userid != $userid) {
|
|
$update->userid = $record->userid = $userid;
|
|
$updated = true;
|
|
}
|
|
|
|
$ip = getremoteaddr();
|
|
if ($record->lastip != $ip) {
|
|
$update->lastip = $record->lastip = $ip;
|
|
$updated = true;
|
|
}
|
|
|
|
$updatefreq = empty($CFG->session_update_timemodified_frequency) ? 20 : $CFG->session_update_timemodified_frequency;
|
|
|
|
if ($record->timemodified == $record->timecreated) {
|
|
// Always do first update of existing record.
|
|
$update->timemodified = $record->timemodified = time();
|
|
$updated = true;
|
|
|
|
} else if ($record->timemodified < time() - $updatefreq) {
|
|
// Update the session modified flag only once every 20 seconds.
|
|
$update->timemodified = $record->timemodified = time();
|
|
$updated = true;
|
|
}
|
|
|
|
if ($updated) {
|
|
$update->id = $record->id;
|
|
$DB->update_record('sessions', $update);
|
|
}
|
|
|
|
return;
|
|
}
|
|
} else {
|
|
if ($record) {
|
|
// This happens when people switch session handlers...
|
|
session_regenerate_id(true);
|
|
$_SESSION = array();
|
|
$DB->delete_records('sessions', array('id'=>$record->id));
|
|
}
|
|
}
|
|
unset($record);
|
|
|
|
$timedout = false;
|
|
if (!isset($_SESSION['SESSION'])) {
|
|
$_SESSION['SESSION'] = new \stdClass();
|
|
if (!$newsid) {
|
|
$timedout = true;
|
|
}
|
|
}
|
|
|
|
$user = null;
|
|
|
|
if (!empty($CFG->opentogoogle)) {
|
|
if (is_web_crawler()) {
|
|
$user = guest_user();
|
|
}
|
|
if (!empty($CFG->guestloginbutton) and !$user and !empty($_SERVER['HTTP_REFERER'])) {
|
|
// Automatically log in users coming from search engine results.
|
|
if (strpos($_SERVER['HTTP_REFERER'], 'google') !== false ) {
|
|
$user = guest_user();
|
|
} else if (strpos($_SERVER['HTTP_REFERER'], 'altavista') !== false ) {
|
|
$user = guest_user();
|
|
}
|
|
}
|
|
}
|
|
|
|
// Setup $USER and insert the session tracking record.
|
|
if ($user) {
|
|
self::set_user($user);
|
|
self::add_session_record($user->id);
|
|
} else {
|
|
self::init_empty_session();
|
|
self::add_session_record(0);
|
|
}
|
|
|
|
if ($timedout) {
|
|
$_SESSION['SESSION']->has_timed_out = true;
|
|
}
|
|
}
|
|
|
|
/**
|
|
* Insert new empty session record.
|
|
* @param int $userid
|
|
* @return \stdClass the new record
|
|
*/
|
|
protected static function add_session_record($userid) {
|
|
global $DB;
|
|
$record = new \stdClass();
|
|
$record->state = 0;
|
|
$record->sid = session_id();
|
|
$record->sessdata = null;
|
|
$record->userid = $userid;
|
|
$record->timecreated = $record->timemodified = time();
|
|
$record->firstip = $record->lastip = getremoteaddr();
|
|
|
|
$record->id = $DB->insert_record('sessions', $record);
|
|
|
|
return $record;
|
|
}
|
|
|
|
/**
|
|
* Do various session security checks.
|
|
*
|
|
* WARNING: $USER and $SESSION are set up later, do not use them yet!
|
|
*/
|
|
protected static function check_security() {
|
|
global $CFG;
|
|
|
|
if (!empty($_SESSION['USER']->id) and !empty($CFG->tracksessionip)) {
|
|
// Make sure current IP matches the one for this session.
|
|
$remoteaddr = getremoteaddr();
|
|
|
|
if (empty($_SESSION['USER']->sessionip)) {
|
|
$_SESSION['USER']->sessionip = $remoteaddr;
|
|
}
|
|
|
|
if ($_SESSION['USER']->sessionip != $remoteaddr) {
|
|
// This is a security feature - terminate the session in case of any doubt.
|
|
self::terminate_current();
|
|
throw new exception('sessionipnomatch2', 'error');
|
|
}
|
|
}
|
|
}
|
|
|
|
/**
|
|
* Login user, to be called from complete_user_login() only.
|
|
* @param \stdClass $user
|
|
*/
|
|
public static function login_user(\stdClass $user) {
|
|
global $DB;
|
|
|
|
// Regenerate session id and delete old session,
|
|
// this helps prevent session fixation attacks from the same domain.
|
|
|
|
$sid = session_id();
|
|
session_regenerate_id(true);
|
|
$DB->delete_records('sessions', array('sid'=>$sid));
|
|
self::add_session_record($user->id);
|
|
|
|
// Let enrol plugins deal with new enrolments if necessary.
|
|
enrol_check_plugins($user);
|
|
|
|
// Setup $USER object.
|
|
self::set_user($user);
|
|
}
|
|
|
|
/**
|
|
* Terminate current user session.
|
|
* @return void
|
|
*/
|
|
public static function terminate_current() {
|
|
global $DB;
|
|
|
|
if (!self::$sessionactive) {
|
|
self::init_empty_session();
|
|
self::$sessionactive = false;
|
|
return;
|
|
}
|
|
|
|
try {
|
|
$DB->delete_records('external_tokens', array('sid'=>session_id(), 'tokentype'=>EXTERNAL_TOKEN_EMBEDDED));
|
|
} catch (\Exception $ignored) {
|
|
// Probably install/upgrade - ignore this problem.
|
|
}
|
|
|
|
// Initialize variable to pass-by-reference to headers_sent(&$file, &$line).
|
|
$file = null;
|
|
$line = null;
|
|
if (headers_sent($file, $line)) {
|
|
error_log('Cannot terminate session properly - headers were already sent in file: '.$file.' on line '.$line);
|
|
}
|
|
|
|
// Write new empty session and make sure the old one is deleted.
|
|
$sid = session_id();
|
|
session_regenerate_id(true);
|
|
$DB->delete_records('sessions', array('sid'=>$sid));
|
|
self::init_empty_session();
|
|
self::add_session_record($_SESSION['USER']->id); // Do not use $USER here because it may not be set up yet.
|
|
session_write_close();
|
|
self::$sessionactive = false;
|
|
}
|
|
|
|
/**
|
|
* No more changes in session expected.
|
|
* Unblocks the sessions, other scripts may start executing in parallel.
|
|
*/
|
|
public static function write_close() {
|
|
if (self::$sessionactive) {
|
|
session_write_close();
|
|
} else {
|
|
if (session_id()) {
|
|
@session_write_close();
|
|
}
|
|
}
|
|
self::$sessionactive = false;
|
|
}
|
|
|
|
/**
|
|
* Does the PHP session with given id exist?
|
|
*
|
|
* The session must exist both in session table and actual
|
|
* session backend and the session must not be timed out.
|
|
*
|
|
* Timeout evaluation is simplified, the auth hooks are not executed.
|
|
*
|
|
* @param string $sid
|
|
* @return bool
|
|
*/
|
|
public static function session_exists($sid) {
|
|
global $DB, $CFG;
|
|
|
|
if (empty($CFG->version)) {
|
|
// Not installed yet, do not try to access database.
|
|
return false;
|
|
}
|
|
|
|
// Note: add sessions->state checking here if it gets implemented.
|
|
if (!$record = $DB->get_record('sessions', array('sid' => $sid), 'id, userid, timemodified')) {
|
|
return false;
|
|
}
|
|
|
|
if (empty($record->userid) or isguestuser($record->userid)) {
|
|
// Ignore guest and not-logged-in timeouts, there is very little risk here.
|
|
} else if ($record->timemodified < time() - $CFG->sessiontimeout) {
|
|
return false;
|
|
}
|
|
|
|
// There is no need the existence of handler storage in public API.
|
|
self::load_handler();
|
|
return self::$handler->session_exists($sid);
|
|
}
|
|
|
|
/**
|
|
* Fake last access for given session, this prevents session timeout.
|
|
* @param string $sid
|
|
*/
|
|
public static function touch_session($sid) {
|
|
global $DB;
|
|
|
|
// Timeouts depend on core sessions table only, no need to update anything in external stores.
|
|
|
|
$sql = "UPDATE {sessions} SET timemodified = :now WHERE sid = :sid";
|
|
$DB->execute($sql, array('now'=>time(), 'sid'=>$sid));
|
|
}
|
|
|
|
/**
|
|
* Terminate all sessions unconditionally.
|
|
*/
|
|
public static function kill_all_sessions() {
|
|
global $DB;
|
|
|
|
self::terminate_current();
|
|
|
|
self::load_handler();
|
|
self::$handler->kill_all_sessions();
|
|
|
|
try {
|
|
$DB->delete_records('sessions');
|
|
} catch (\dml_exception $ignored) {
|
|
// Do not show any warnings - might be during upgrade/installation.
|
|
}
|
|
}
|
|
|
|
/**
|
|
* Terminate give session unconditionally.
|
|
* @param string $sid
|
|
*/
|
|
public static function kill_session($sid) {
|
|
global $DB;
|
|
|
|
self::load_handler();
|
|
|
|
if ($sid === session_id()) {
|
|
self::write_close();
|
|
}
|
|
|
|
self::$handler->kill_session($sid);
|
|
|
|
$DB->delete_records('sessions', array('sid'=>$sid));
|
|
}
|
|
|
|
/**
|
|
* Terminate all sessions of given user unconditionally.
|
|
* @param int $userid
|
|
* @param string $keepsid keep this sid if present
|
|
*/
|
|
public static function kill_user_sessions($userid, $keepsid = null) {
|
|
global $DB;
|
|
|
|
$sessions = $DB->get_records('sessions', array('userid'=>$userid), 'id DESC', 'id, sid');
|
|
foreach ($sessions as $session) {
|
|
if ($keepsid and $keepsid === $session->sid) {
|
|
continue;
|
|
}
|
|
self::kill_session($session->sid);
|
|
}
|
|
}
|
|
|
|
/**
|
|
* Terminate other sessions of current user depending
|
|
* on $CFG->limitconcurrentlogins restriction.
|
|
*
|
|
* This is expected to be called right after complete_user_login().
|
|
*
|
|
* NOTE:
|
|
* * Do not use from SSO auth plugins, this would not work.
|
|
* * Do not use from web services because they do not have sessions.
|
|
*
|
|
* @param int $userid
|
|
* @param string $sid session id to be always keep, usually the current one
|
|
* @return void
|
|
*/
|
|
public static function apply_concurrent_login_limit($userid, $sid = null) {
|
|
global $CFG, $DB;
|
|
|
|
// NOTE: the $sid parameter is here mainly to allow testing,
|
|
// in most cases it should be current session id.
|
|
|
|
if (isguestuser($userid) or empty($userid)) {
|
|
// This applies to real users only!
|
|
return;
|
|
}
|
|
|
|
if (empty($CFG->limitconcurrentlogins) or $CFG->limitconcurrentlogins < 0) {
|
|
return;
|
|
}
|
|
|
|
$count = $DB->count_records('sessions', array('userid' => $userid));
|
|
|
|
if ($count <= $CFG->limitconcurrentlogins) {
|
|
return;
|
|
}
|
|
|
|
$i = 0;
|
|
$select = "userid = :userid";
|
|
$params = array('userid' => $userid);
|
|
if ($sid) {
|
|
if ($DB->record_exists('sessions', array('sid' => $sid, 'userid' => $userid))) {
|
|
$select .= " AND sid <> :sid";
|
|
$params['sid'] = $sid;
|
|
$i = 1;
|
|
}
|
|
}
|
|
|
|
$sessions = $DB->get_records_select('sessions', $select, $params, 'timecreated DESC', 'id, sid');
|
|
foreach ($sessions as $session) {
|
|
$i++;
|
|
if ($i <= $CFG->limitconcurrentlogins) {
|
|
continue;
|
|
}
|
|
self::kill_session($session->sid);
|
|
}
|
|
}
|
|
|
|
/**
|
|
* Set current user.
|
|
*
|
|
* @param \stdClass $user record
|
|
*/
|
|
public static function set_user(\stdClass $user) {
|
|
$GLOBALS['USER'] = $user;
|
|
unset($GLOBALS['USER']->description); // Conserve memory.
|
|
unset($GLOBALS['USER']->password); // Improve security.
|
|
if (isset($GLOBALS['USER']->lang)) {
|
|
// Make sure it is a valid lang pack name.
|
|
$GLOBALS['USER']->lang = clean_param($GLOBALS['USER']->lang, PARAM_LANG);
|
|
}
|
|
|
|
// Relink session with global $USER just in case it got unlinked somehow.
|
|
$_SESSION['USER'] =& $GLOBALS['USER'];
|
|
|
|
// Init session key.
|
|
sesskey();
|
|
}
|
|
|
|
/**
|
|
* Periodic timed-out session cleanup.
|
|
*/
|
|
public static function gc() {
|
|
global $CFG, $DB;
|
|
|
|
// This may take a long time...
|
|
\core_php_time_limit::raise();
|
|
|
|
$maxlifetime = $CFG->sessiontimeout;
|
|
|
|
try {
|
|
// Kill all sessions of deleted and suspended users without any hesitation.
|
|
$rs = $DB->get_recordset_select('sessions', "userid IN (SELECT id FROM {user} WHERE deleted <> 0 OR suspended <> 0)", array(), 'id DESC', 'id, sid');
|
|
foreach ($rs as $session) {
|
|
self::kill_session($session->sid);
|
|
}
|
|
$rs->close();
|
|
|
|
// Kill sessions of users with disabled plugins.
|
|
$auth_sequence = get_enabled_auth_plugins(true);
|
|
$auth_sequence = array_flip($auth_sequence);
|
|
unset($auth_sequence['nologin']); // No login means user cannot login.
|
|
$auth_sequence = array_flip($auth_sequence);
|
|
|
|
list($notplugins, $params) = $DB->get_in_or_equal($auth_sequence, SQL_PARAMS_QM, '', false);
|
|
$rs = $DB->get_recordset_select('sessions', "userid IN (SELECT id FROM {user} WHERE auth $notplugins)", $params, 'id DESC', 'id, sid');
|
|
foreach ($rs as $session) {
|
|
self::kill_session($session->sid);
|
|
}
|
|
$rs->close();
|
|
|
|
// Now get a list of time-out candidates - real users only.
|
|
$sql = "SELECT u.*, s.sid, s.timecreated AS s_timecreated, s.timemodified AS s_timemodified
|
|
FROM {user} u
|
|
JOIN {sessions} s ON s.userid = u.id
|
|
WHERE s.timemodified < :purgebefore AND u.id <> :guestid";
|
|
$params = array('purgebefore' => (time() - $maxlifetime), 'guestid'=>$CFG->siteguest);
|
|
|
|
$authplugins = array();
|
|
foreach ($auth_sequence as $authname) {
|
|
$authplugins[$authname] = get_auth_plugin($authname);
|
|
}
|
|
$rs = $DB->get_recordset_sql($sql, $params);
|
|
foreach ($rs as $user) {
|
|
foreach ($authplugins as $authplugin) {
|
|
/** @var \auth_plugin_base $authplugin*/
|
|
if ($authplugin->ignore_timeout_hook($user, $user->sid, $user->s_timecreated, $user->s_timemodified)) {
|
|
continue;
|
|
}
|
|
}
|
|
self::kill_session($user->sid);
|
|
}
|
|
$rs->close();
|
|
|
|
// Delete expired sessions for guest user account, give them larger timeout, there is no security risk here.
|
|
$params = array('purgebefore' => (time() - ($maxlifetime * 5)), 'guestid'=>$CFG->siteguest);
|
|
$rs = $DB->get_recordset_select('sessions', 'userid = :guestid AND timemodified < :purgebefore', $params, 'id DESC', 'id, sid');
|
|
foreach ($rs as $session) {
|
|
self::kill_session($session->sid);
|
|
}
|
|
$rs->close();
|
|
|
|
// Delete expired sessions for userid = 0 (not logged in), better kill them asap to release memory.
|
|
$params = array('purgebefore' => (time() - $maxlifetime));
|
|
$rs = $DB->get_recordset_select('sessions', 'userid = 0 AND timemodified < :purgebefore', $params, 'id DESC', 'id, sid');
|
|
foreach ($rs as $session) {
|
|
self::kill_session($session->sid);
|
|
}
|
|
$rs->close();
|
|
|
|
// Cleanup letfovers from the first browser access because it may set multiple cookies and then use only one.
|
|
$params = array('purgebefore' => (time() - 60*3));
|
|
$rs = $DB->get_recordset_select('sessions', 'userid = 0 AND timemodified = timecreated AND timemodified < :purgebefore', $params, 'id ASC', 'id, sid');
|
|
foreach ($rs as $session) {
|
|
self::kill_session($session->sid);
|
|
}
|
|
$rs->close();
|
|
|
|
} catch (\Exception $ex) {
|
|
debugging('Error gc-ing sessions: '.$ex->getMessage(), DEBUG_NORMAL, $ex->getTrace());
|
|
}
|
|
}
|
|
|
|
/**
|
|
* Is current $USER logged-in-as somebody else?
|
|
* @return bool
|
|
*/
|
|
public static function is_loggedinas() {
|
|
return !empty($GLOBALS['USER']->realuser);
|
|
}
|
|
|
|
/**
|
|
* Returns the $USER object ignoring current login-as session
|
|
* @return \stdClass user object
|
|
*/
|
|
public static function get_realuser() {
|
|
if (self::is_loggedinas()) {
|
|
return $_SESSION['REALUSER'];
|
|
} else {
|
|
return $GLOBALS['USER'];
|
|
}
|
|
}
|
|
|
|
/**
|
|
* Login as another user - no security checks here.
|
|
* @param int $userid
|
|
* @param \context $context
|
|
* @return void
|
|
*/
|
|
public static function loginas($userid, \context $context) {
|
|
global $USER;
|
|
|
|
if (self::is_loggedinas()) {
|
|
return;
|
|
}
|
|
|
|
// Switch to fresh new $_SESSION.
|
|
$_SESSION = array();
|
|
$_SESSION['REALSESSION'] = clone($GLOBALS['SESSION']);
|
|
$GLOBALS['SESSION'] = new \stdClass();
|
|
$_SESSION['SESSION'] =& $GLOBALS['SESSION'];
|
|
|
|
// Create the new $USER object with all details and reload needed capabilities.
|
|
$_SESSION['REALUSER'] = clone($GLOBALS['USER']);
|
|
$user = get_complete_user_data('id', $userid);
|
|
$user->realuser = $_SESSION['REALUSER']->id;
|
|
$user->loginascontext = $context;
|
|
|
|
// Let enrol plugins deal with new enrolments if necessary.
|
|
enrol_check_plugins($user);
|
|
|
|
// Create event before $USER is updated.
|
|
$event = \core\event\user_loggedinas::create(
|
|
array(
|
|
'objectid' => $USER->id,
|
|
'context' => $context,
|
|
'relateduserid' => $userid,
|
|
'other' => array(
|
|
'originalusername' => fullname($USER, true),
|
|
'loggedinasusername' => fullname($user, true)
|
|
)
|
|
)
|
|
);
|
|
// Set up global $USER.
|
|
\core\session\manager::set_user($user);
|
|
$event->trigger();
|
|
}
|
|
|
|
/**
|
|
* Add a JS session keepalive to the page.
|
|
*
|
|
* A JS session keepalive script will be called to update the session modification time every $frequency seconds.
|
|
*
|
|
* Upon failure, the specified error message will be shown to the user.
|
|
*
|
|
* @param string $identifier The string identifier for the message to show on failure.
|
|
* @param string $component The string component for the message to show on failure.
|
|
* @param int $frequency The update frequency in seconds.
|
|
* @throws coding_exception IF the frequency is longer than the session lifetime.
|
|
*/
|
|
public static function keepalive($identifier = 'sessionerroruser', $component = 'error', $frequency = null) {
|
|
global $CFG, $PAGE;
|
|
|
|
if ($frequency) {
|
|
if ($frequency > $CFG->sessiontimeout) {
|
|
// Sanity check the frequency.
|
|
throw new \coding_exception('Keepalive frequency is longer than the session lifespan.');
|
|
}
|
|
} else {
|
|
// A frequency of sessiontimeout / 3 allows for one missed request whilst still preserving the session.
|
|
$frequency = $CFG->sessiontimeout / 3;
|
|
}
|
|
|
|
// Add the session keepalive script to the list of page output requirements.
|
|
$sessionkeepaliveurl = new \moodle_url('/lib/sessionkeepalive_ajax.php');
|
|
$PAGE->requires->string_for_js($identifier, $component);
|
|
$PAGE->requires->yui_module('moodle-core-checknet', 'M.core.checknet.init', array(array(
|
|
// The JS config takes this is milliseconds rather than seconds.
|
|
'frequency' => $frequency * 1000,
|
|
'message' => array($identifier, $component),
|
|
'uri' => $sessionkeepaliveurl->out(),
|
|
)));
|
|
}
|
|
|
|
}
|