<?php
/**
* Joomla! Content Management System
*
* @copyright Copyright (C) 2005 - 2019 Open Source Matters, Inc. All rights reserved.
* @license GNU General Public License version 2 or later; see LICENSE.txt
*/
namespace Joomla\CMS\Session;
defined('JPATH_PLATFORM') or die;
use Joomla\CMS\Application\ApplicationHelper;
use Joomla\CMS\Input\Input;
use Joomla\CMS\User\UserHelper;
/**
* Class for managing HTTP sessions
*
* Provides access to session-state values as well as session-level
* settings and lifetime management methods.
* Based on the standard PHP session handling mechanism it provides
* more advanced features such as expire timeouts.
*
* @since 1.7.0
*/
class Session implements \IteratorAggregate
{
/**
* Internal state.
* One of 'inactive'|'active'|'expired'|'destroyed'|'error'
*
* @var string
* @see Session::getState()
* @since 1.7.0
*/
protected $_state = 'inactive';
/**
* Maximum age of unused session in seconds
*
* @var string
* @since 1.7.0
*/
protected $_expire = 900;
/**
* The session store object.
*
* @var \JSessionStorage
* @since 1.7.0
*/
protected $_store = null;
/**
* Security policy.
* List of checks that will be done.
*
* Default values:
* - fix_browser
* - fix_adress
*
* @var array
* @since 1.7.0
*/
protected $_security = array('fix_browser');
/**
* Session instances container.
*
* @var Session
* @since 1.7.3
*/
protected static $instance;
/**
* The type of storage for the session.
*
* @var string
* @since 3.0.1
*/
protected $storeName;
/**
* Holds the \JInput object
*
* @var \JInput
* @since 3.0.1
*/
private $_input = null;
/**
* Holds the event dispatcher object
*
* @var \JEventDispatcher
* @since 3.0.1
*/
private $_dispatcher = null;
/**
* Holds the event dispatcher object
*
* @var \JSessionHandlerInterface
* @since 3.5
*/
protected $_handler = null;
/**
* Internal data store for the session data
*
* @var \Joomla\Registry\Registry
*/
protected $data;
/**
* Constructor
*
* @param string $store The type of storage for the session.
* @param array $options Optional parameters
* @param \JSessionHandlerInterface $handlerInterface The session handler
*
* @since 1.7.0
*/
public function __construct($store = 'none', array $options = array(), \JSessionHandlerInterface $handlerInterface = null)
{
// Set the session handler
$this->_handler = $handlerInterface instanceof \JSessionHandlerInterface ? $handlerInterface : new \JSessionHandlerJoomla($options);
// Initialize the data variable, let's avoid fatal error if the session is not corretly started (ie in CLI).
$this->data = new \Joomla\Registry\Registry;
// Clear any existing sessions
if ($this->_handler->getId())
{
$this->_handler->clear();
}
// Create handler
$this->_store = \JSessionStorage::getInstance($store, $options);
$this->storeName = $store;
$this->_setOptions($options);
$this->_state = 'inactive';
}
/**
* Magic method to get read-only access to properties.
*
* @param string $name Name of property to retrieve
*
* @return mixed The value of the property
*
* @since 3.0.1
*/
public function __get($name)
{
if ($name === 'storeName')
{
return $this->$name;
}
if ($name === 'state' || $name === 'expire')
{
$property = '_' . $name;
return $this->$property;
}
}
/**
* Returns the global Session object, only creating it if it doesn't already exist.
*
* @param string $store The type of storage for the session.
* @param array $options An array of configuration options.
* @param \JSessionHandlerInterface $handlerInterface The session handler
*
* @return Session The Session object.
*
* @since 1.7.0
*/
public static function getInstance($store, $options, \JSessionHandlerInterface $handlerInterface = null)
{
if (!is_object(self::$instance))
{
self::$instance = new Session($store, $options, $handlerInterface);
}
return self::$instance;
}
/**
* Get current state of session
*
* @return string The session state
*
* @since 1.7.0
*/
public function getState()
{
return $this->_state;
}
/**
* Get expiration time in seconds
*
* @return integer The session expiration time in seconds
*
* @since 1.7.0
*/
public function getExpire()
{
return $this->_expire;
}
/**
* Get a session token, if a token isn't set yet one will be generated.
*
* Tokens are used to secure forms from spamming attacks. Once a token
* has been generated the system will check the post request to see if
* it is present, if not it will invalidate the session.
*
* @param boolean $forceNew If true, force a new token to be created
*
* @return string The session token
*
* @since 1.7.0
*/
public function getToken($forceNew = false)
{
$token = $this->get('session.token');
// Create a token
if ($token === null || $forceNew)
{
$token = $this->_createToken();
$this->set('session.token', $token);
}
return $token;
}
/**
* Method to determine if a token exists in the session. If not the
* session will be set to expired
*
* @param string $tCheck Hashed token to be verified
* @param boolean $forceExpire If true, expires the session
*
* @return boolean
*
* @since 1.7.0
*/
public function hasToken($tCheck, $forceExpire = true)
{
// Check if a token exists in the session
$tStored = $this->get('session.token');
// Check token
if (($tStored !== $tCheck))
{
if ($forceExpire)
{
$this->_state = 'expired';
}
return false;
}
return true;
}
/**
* Method to determine a hash for anti-spoofing variable names
*
* @param boolean $forceNew If true, force a new token to be created
*
* @return string Hashed var name
*
* @since 1.7.0
*/
public static function getFormToken($forceNew = false)
{
$user = \JFactory::getUser();
$session = \JFactory::getSession();
return ApplicationHelper::getHash($user->get('id', 0) . $session->getToken($forceNew));
}
/**
* Retrieve an external iterator.
*
* @return \ArrayIterator
*
* @since 3.0.1
*/
public function getIterator()
{
return new \ArrayIterator($this->getData());
}
/**
* Checks for a form token in the request.
*
* Use in conjunction with \JHtml::_('form.token') or Session::getFormToken.
*
* @param string $method The request method in which to look for the token key.
*
* @return boolean True if found and valid, false otherwise.
*
* @since 3.0.0
*/
public static function checkToken($method = 'post')
{
$token = self::getFormToken();
$app = \JFactory::getApplication();
// Check from header first
if ($token === $app->input->server->get('HTTP_X_CSRF_TOKEN', '', 'alnum'))
{
return true;
}
// Then fallback to HTTP query
if (!$app->input->$method->get($token, '', 'alnum'))
{
if (\JFactory::getSession()->isNew())
{
// Redirect to login screen.
$app->enqueueMessage(\JText::_('JLIB_ENVIRONMENT_SESSION_EXPIRED'), 'warning');
$app->redirect(\JRoute::_('index.php'));
return true;
}
return false;
}
return true;
}
/**
* Get session name
*
* @return string The session name
*
* @since 1.7.0
*/
public function getName()
{
if ($this->getState() === 'destroyed')
{
// @TODO : raise error
return;
}
return $this->_handler->getName();
}
/**
* Get session id
*
* @return string The session id
*
* @since 1.7.0
*/
public function getId()
{
if ($this->getState() === 'destroyed')
{
// @TODO : raise error
return;
}
return $this->_handler->getId();
}
/**
* Returns a clone of the internal data pointer
*
* @return \Joomla\Registry\Registry
*/
public function getData()
{
return clone $this->data;
}
/**
* Get the session handlers
*
* @return array An array of available session handlers
*
* @since 1.7.0
*/
public static function getStores()
{
$connectors = array();
// Get an iterator and loop trough the driver classes.
$iterator = new \DirectoryIterator(JPATH_LIBRARIES . '/joomla/session/storage');
/** @type $file \DirectoryIterator */
foreach ($iterator as $file)
{
$fileName = $file->getFilename();
// Only load for php files.
if (!$file->isFile() || $file->getExtension() != 'php')
{
continue;
}
// Derive the class name from the type.
$class = str_ireplace('.php', '', 'JSessionStorage' . ucfirst(trim($fileName)));
// If the class doesn't exist we have nothing left to do but look at the next type. We did our best.
if (!class_exists($class))
{
continue;
}
// Sweet! Our class exists, so now we just need to know if it passes its test method.
if ($class::isSupported())
{
// Connector names should not have file extensions.
$connectors[] = str_ireplace('.php', '', $fileName);
}
}
return $connectors;
}
/**
* Shorthand to check if the session is active
*
* @return boolean
*
* @since 3.0.1
*/
public function isActive()
{
return (bool) ($this->getState() == 'active');
}
/**
* Check whether this session is currently created
*
* @return boolean True on success.
*
* @since 1.7.0
*/
public function isNew()
{
return (bool) ($this->get('session.counter') === 1);
}
/**
* Check whether this session is currently created
*
* @param Input $input Input object for the session to use.
* @param \JEventDispatcher $dispatcher Dispatcher object for the session to use.
*
* @return void
*
* @since 3.0.1
*/
public function initialise(Input $input, \JEventDispatcher $dispatcher = null)
{
// With the introduction of the handler class this variable is no longer required
// however we keep setting it for b/c
$this->_input = $input;
// Nasty workaround to deal in a b/c way with JInput being required in the 3.4+ Handler class.
if ($this->_handler instanceof \JSessionHandlerJoomla)
{
$this->_handler->input = $input;
}
$this->_dispatcher = $dispatcher;
}
/**
* Get data from the session store
*
* @param string $name Name of a variable
* @param mixed $default Default value of a variable if not set
* @param string $namespace Namespace to use, default to 'default'
*
* @return mixed Value of a variable
*
* @since 1.7.0
*/
public function get($name, $default = null, $namespace = 'default')
{
if (!$this->isActive())
{
$this->start();
}
// Add prefix to namespace to avoid collisions
$namespace = '__' . $namespace;
if ($this->getState() === 'destroyed')
{
// @TODO :: generated error here
$error = null;
return $error;
}
return $this->data->get($namespace . '.' . $name, $default);
}
/**
* Set data into the session store.
*
* @param string $name Name of a variable.
* @param mixed $value Value of a variable.
* @param string $namespace Namespace to use, default to 'default'.
*
* @return mixed Old value of a variable.
*
* @since 1.7.0
*/
public function set($name, $value = null, $namespace = 'default')
{
if (!$this->isActive())
{
$this->start();
}
// Add prefix to namespace to avoid collisions
$namespace = '__' . $namespace;
if ($this->getState() !== 'active')
{
// @TODO :: generated error here
return;
}
$prev = $this->data->get($namespace . '.' . $name, null);
$this->data->set($namespace . '.' . $name, $value);
return $prev;
}
/**
* Check whether data exists in the session store
*
* @param string $name Name of variable
* @param string $namespace Namespace to use, default to 'default'
*
* @return boolean True if the variable exists
*
* @since 1.7.0
*/
public function has($name, $namespace = 'default')
{
if (!$this->isActive())
{
$this->start();
}
// Add prefix to namespace to avoid collisions.
$namespace = '__' . $namespace;
if ($this->getState() !== 'active')
{
// @TODO :: generated error here
return;
}
return !is_null($this->data->get($namespace . '.' . $name, null));
}
/**
* Unset data from the session store
*
* @param string $name Name of variable
* @param string $namespace Namespace to use, default to 'default'
*
* @return mixed The value from session or NULL if not set
*
* @since 1.7.0
*/
public function clear($name, $namespace = 'default')
{
if (!$this->isActive())
{
$this->start();
}
// Add prefix to namespace to avoid collisions
$namespace = '__' . $namespace;
if ($this->getState() !== 'active')
{
// @TODO :: generated error here
return;
}
return $this->data->set($namespace . '.' . $name, null);
}
/**
* Start a session.
*
* @return void
*
* @since 3.0.1
*/
public function start()
{
if ($this->getState() === 'active')
{
return;
}
$this->_start();
$this->_state = 'active';
// Initialise the session
$this->_setCounter();
$this->_setTimers();
// Perform security checks
if (!$this->_validate())
{
// If the session isn't valid because it expired try to restart it
// else destroy it.
if ($this->_state === 'expired')
{
$this->restart();
}
else
{
$this->destroy();
}
}
if ($this->_dispatcher instanceof \JEventDispatcher)
{
$this->_dispatcher->trigger('onAfterSessionStart');
}
}
/**
* Start a session.
*
* Creates a session (or resumes the current one based on the state of the session)
*
* @return boolean true on success
*
* @since 1.7.0
*/
protected function _start()
{
$this->_handler->start();
// Ok let's unserialize the whole thing
// Try loading data from the session
if (isset($_SESSION['joomla']) && !empty($_SESSION['joomla']))
{
$data = $_SESSION['joomla'];
$data = base64_decode($data);
$this->data = unserialize($data);
}
// Temporary, PARTIAL, data migration of existing session data to avoid logout on update from J < 3.4.7
if (isset($_SESSION['__default']) && !empty($_SESSION['__default']))
{
$migratableKeys = array(
'user',
'session.token',
'session.counter',
'session.timer.start',
'session.timer.last',
'session.timer.now'
);
foreach ($migratableKeys as $migratableKey)
{
if (!empty($_SESSION['__default'][$migratableKey]))
{
// Don't overwrite existing session data
if (!is_null($this->data->get('__default.' . $migratableKey, null)))
{
continue;
}
$this->data->set('__default.' . $migratableKey, $_SESSION['__default'][$migratableKey]);
unset($_SESSION['__default'][$migratableKey]);
}
}
/**
* Finally, empty the __default key since we no longer need it. Don't unset it completely, we need this
* for the administrator/components/com_admin/script.php to detect upgraded sessions and perform a full
* session cleanup.
*/
$_SESSION['__default'] = array();
}
return true;
}
/**
* Frees all session variables and destroys all data registered to a session
*
* This method resets the data pointer and destroys all of the data associated
* with the current session in its storage. It forces a new session to be
* started after this method is called. It does not unset the session cookie.
*
* @return boolean True on success
*
* @see session_destroy()
* @see session_unset()
* @since 1.7.0
*/
public function destroy()
{
// Session was already destroyed
if ($this->getState() === 'destroyed')
{
return true;
}
// Kill session
$this->_handler->clear();
// Create new data storage
$this->data = new \Joomla\Registry\Registry;
$this->_state = 'destroyed';
return true;
}
/**
* Restart an expired or locked session.
*
* @return boolean True on success
*
* @see Session::destroy()
* @since 1.7.0
*/
public function restart()
{
$this->destroy();
if ($this->getState() !== 'destroyed')
{
// @TODO :: generated error here
return false;
}
// Re-register the session handler after a session has been destroyed, to avoid PHP bug
$this->_store->register();
$this->_state = 'restart';
// Regenerate session id
$this->_start();
$this->_handler->regenerate(true, null);
$this->_state = 'active';
if (!$this->_validate())
{
/**
* Destroy the session if it's not valid - we can't restart the session here unlike in the start method
* else we risk recursion.
*/
$this->destroy();
}
$this->_setCounter();
return true;
}
/**
* Create a new session and copy variables from the old one
*
* @return boolean $result true on success
*
* @since 1.7.0
*/
public function fork()
{
if ($this->getState() !== 'active')
{
// @TODO :: generated error here
return false;
}
// Restart session with new id
$this->_handler->regenerate(true, null);
return true;
}
/**
* Writes session data and ends session
*
* Session data is usually stored after your script terminated without the need
* to call Session::close(), but as session data is locked to prevent concurrent
* writes only one script may operate on a session at any time. When using
* framesets together with sessions you will experience the frames loading one
* by one due to this locking. You can reduce the time needed to load all the
* frames by ending the session as soon as all changes to session variables are
* done.
*
* @return void
*
* @since 1.7.0
*/
public function close()
{
$this->_handler->save();
$this->_state = 'inactive';
}
/**
* Delete expired session data
*
* @return boolean True on success, false otherwise.
*
* @since 3.8.6
*/
public function gc()
{
return $this->_store->gc($this->getExpire());
}
/**
* Set the session handler
*
* @param \JSessionHandlerInterface $handler The session handler
*
* @return void
*/
public function setHandler(\JSessionHandlerInterface $handler)
{
$this->_handler = $handler;
}
/**
* Create a token-string
*
* @param integer $length Length of string
*
* @return string Generated token
*
* @since 1.7.0
*/
protected function _createToken($length = 32)
{
return UserHelper::genRandomPassword($length);
}
/**
* Set counter of session usage
*
* @return boolean True on success
*
* @since 1.7.0
*/
protected function _setCounter()
{
$counter = $this->get('session.counter', 0);
++$counter;
$this->set('session.counter', $counter);
return true;
}
/**
* Set the session timers
*
* @return boolean True on success
*
* @since 1.7.0
*/
protected function _setTimers()
{
if (!$this->has('session.timer.start'))
{
$start = time();
$this->set('session.timer.start', $start);
$this->set('session.timer.last', $start);
$this->set('session.timer.now', $start);
}
$this->set('session.timer.last', $this->get('session.timer.now'));
$this->set('session.timer.now', time());
return true;
}
/**
* Set additional session options
*
* @param array $options List of parameter
*
* @return boolean True on success
*
* @since 1.7.0
*/
protected function _setOptions(array $options)
{
// Set name
if (isset($options['name']))
{
$this->_handler->setName(md5($options['name']));
}
// Set id
if (isset($options['id']))
{
$this->_handler->setId($options['id']);
}
// Set expire time
if (isset($options['expire']))
{
$this->_expire = $options['expire'];
}
// Get security options
if (isset($options['security']))
{
$this->_security = explode(',', $options['security']);
}
// Sync the session maxlifetime
if (!headers_sent())
{
ini_set('session.gc_maxlifetime', $this->_expire);
}
return true;
}
/**
* Do some checks for security reason
*
* - timeout check (expire)
* - ip-fixiation
* - browser-fixiation
*
* If one check failed, session data has to be cleaned.
*
* @param boolean $restart Reactivate session
*
* @return boolean True on success
*
* @link http://shiflett.org/articles/the-truth-about-sessions
* @since 1.7.0
*/
protected function _validate($restart = false)
{
// Allow to restart a session
if ($restart)
{
$this->_state = 'active';
$this->set('session.client.address', null);
$this->set('session.client.forwarded', null);
$this->set('session.client.browser', null);
$this->set('session.token', null);
}
// Check if session has expired
if ($this->getExpire())
{
$curTime = $this->get('session.timer.now', 0);
$maxTime = $this->get('session.timer.last', 0) + $this->getExpire();
// Empty session variables
if ($maxTime < $curTime)
{
$this->_state = 'expired';
return false;
}
}
// Check for client address
if (in_array('fix_adress', $this->_security) && isset($_SERVER['REMOTE_ADDR'])
&& filter_var($_SERVER['REMOTE_ADDR'], FILTER_VALIDATE_IP) !== false)
{
$ip = $this->get('session.client.address');
if ($ip === null)
{
$this->set('session.client.address', $_SERVER['REMOTE_ADDR']);
}
elseif ($_SERVER['REMOTE_ADDR'] !== $ip)
{
$this->_state = 'error';
return false;
}
}
// Record proxy forwarded for in the session in case we need it later
if (isset($_SERVER['HTTP_X_FORWARDED_FOR']) && filter_var($_SERVER['HTTP_X_FORWARDED_FOR'], FILTER_VALIDATE_IP) !== false)
{
$this->set('session.client.forwarded', $_SERVER['HTTP_X_FORWARDED_FOR']);
}
return true;
}
}