<?php
/* SVN FILE: $Id$ */
/**
* Session class for Cake.
*
* Cake abstracts the handling of sessions.
* There are several convenient methods to access session information.
* This class is the implementation of those methods.
* They are mostly used by the Session Component.
*
* PHP versions 4 and 5
*
* CakePHP : Rapid Development Framework <http://www.cakephp.org/>
* Copyright (c) 2006, Cake Software Foundation, Inc.
* 1785 E. Sahara Avenue, Suite 490-204
* Las Vegas, Nevada 89104
*
* Licensed under The MIT License
* Redistributions of files must retain the above copyright notice.
*
* @filesource
* @copyright Copyright (c) 2006, Cake Software Foundation, Inc.
* @link http://www.cakefoundation.org/projects/info/cakephp CakePHP Project
* @package cake
* @subpackage cake.cake.libs
* @since CakePHP v .0.10.0.1222
* @version $Revision$
* @modifiedby $LastChangedBy$
* @lastmodified $Date$
* @license http://www.opensource.org/licenses/mit-license.php The MIT License
*/
/**
* Database name for cake sessions.
*
*/
if (!defined('CAKE_SESSION_TABLE')) {
define('CAKE_SESSION_TABLE', 'cake_sessions');
}
if (CAKE_SESSION_SAVE === 'database') {
uses('model' . DS . 'connection_manager');
}
/**
* Session class for Cake.
*
* Cake abstracts the handling of sessions. There are several convenient methods to access session information.
* This class is the implementation of those methods. They are mostly used by the Session Component.
*
* @package cake
* @subpackage cake.cake.libs
*/
class CakeSession extends Object {
/**
* True if the Session is still valid
*
* @var boolean
* @access public
*/
var $valid = false;
/**
* Error messages for this session
*
* @var array
* @access public
*/
var $error = false;
/**
* User agent string
*
* @var string
* @access protected
*/
var $_userAgent = false;
/**
* Path to where the session is active.
*
* @var string
* @access public
*/
var $path = false;
/**
* Error number of last occurred error
*
* @var integer
* @access public
*/
var $lastError = null;
/**
* CAKE_SECURITY setting, "high", "medium", or "low".
*
* @var string
* @access public
*/
var $security = null;
/**
* Start time for this session.
*
* @var integer
* @access public
*/
var $time = false;
/**
* Time when this session becomes invalid.
*
* @var integer
* @access public
*/
var $sessionTime = false;
/**
* Constructor.
*
* @param string $base The base path for the Session
* @param boolean $start
* @access public
*/
function __construct($base = null, $start = true) {
if($start === true) {
$this->host = env('HTTP_HOST');
if (empty($base) || strpos($base, '?')) {
$this->path = '/';
} else {
$this->path = $base;
}
if (strpos($this->host, ':') !== false) {
$this->host = substr($this->host, 0, strpos($this->host, ':'));
}
if (env('HTTP_USER_AGENT') != null) {
$this->_userAgent = md5(env('HTTP_USER_AGENT') . CAKE_SESSION_STRING);
} else {
$this->_userAgent = "";
}
$this->time = time();
$this->sessionTime = $this->time + (Security::inactiveMins() * CAKE_SESSION_TIMEOUT);
$this->security = CAKE_SECURITY;
if (function_exists('session_write_close')) {
session_write_close();
}
$this->__initSession();
session_cache_limiter ("must-revalidate");
session_start();
header ('P3P: CP="NOI ADM DEV PSAi COM NAV OUR OTRo STP IND DEM"');
$this->__checkValid();
}
parent::__construct();
}
/**
* Returns true if given variable is set in session.
*
* @param string $name Variable name to check for
* @return boolean True if variable is there
* @access public
*/
function checkSessionVar($name) {
$expression = "return isset(" . $this->__sessionVarNames($name) . ");";
return eval($expression);
}
/**
* Removes a variable from session.
*
* @param string $name Session variable to remove
* @return boolean Success
* @access public
*/
function delSessionVar($name) {
if ($this->checkSessionVar($name)) {
$var = $this->__sessionVarNames($name);
eval ("unset($var);");
return true;
}
$this->__setError(2, "$name doesn't exist");
return false;
}
/**
* Return error description for given error number.
*
* @param int $errorNumber
* @return string Error as string
* @access public
*/
function getError($errorNumber) {
if (!is_array($this->error) || !array_key_exists($errorNumber, $this->error)) {
return false;
} else {
return $this->error[$errorNumber];
}
}
/**
* Returns last occurred error as a string, if any.
*
* @return mixed Error description as a string, or false.
* @access public
*/
function getLastError() {
if ($this->lastError) {
return $this->getError($this->lastError);
} else {
return false;
}
}
/**
* Returns true if session is valid.
*
* @return boolean
* @access public
*/
function isValid() {
return $this->valid;
}
/**
* Returns given session variable, or all of them, if no parameters given.
*
* @param mixed $name The name of the session variable
* @return mixed The value of the session variable
* @access public
*/
function readSessionVar($name = null) {
if (is_null($name)) {
return $this->returnSessionVars();
}
if ($this->checkSessionVar($name)) {
$result = eval("return " . $this->__sessionVarNames($name) . ";");
return $result;
}
$this->__setError(2, "$name doesn't exist");
$return = null;
return $return;
}
/**
* Returns all session variables.
*
* @return mixed Full $_SESSION array, or false on error.
* @access public
*/
function returnSessionVars() {
if (!empty($_SESSION)) {
$result = eval("return \$_SESSION;");
return $result;
}
$this->__setError(2, "No Session vars set");
return false;
}
/**
* Writes value to given session variable name.
*
* @param mixed $name
* @param string $value
* @return void
*/
function writeSessionVar($name, $value) {
$expression = $this->__sessionVarNames($name);
$expression .= " = \$value;";
eval ($expression);
}
/**
* Method called on close of a database
* session
*
* @return boolean
* @access private
*/
function __close() {
return true;
}
/**
* Method called on the destruction of a
* database session
*
* @param integer $key
* @return boolean
* @access private
*/
function __destroy($key) {
$db =& ConnectionManager::getDataSource('default');
$table = $db->fullTableName(CAKE_SESSION_TABLE);
$db->execute("DELETE FROM " . $db->name($table) . " WHERE " . $db->name($table.'.id') . " = " . $db->value($key, 'integer'));
return true;
}
/**
* Helper method to destroy invalid sessions.
*
* @return void
* @access private
*/
function destroyInvalid() {
$sessionpath = session_save_path();
if (empty($sessionpath)) {
$sessionpath = "/tmp";
}
if (isset($_COOKIE[session_name()])) {
setcookie(CAKE_SESSION_COOKIE, '', time() - 42000, $this->path);
}
$file = $sessionpath . DS . "sess_" . session_id();
@session_destroy();
@unlink ($file);
$this->__construct($this->path);
$this->renew();
}
/**
* Helper function called on gc for
* database sessions
*
* @param unknown_type $expires
* @return boolean
* @access private
*/
function __gc($expires) {
$db =& ConnectionManager::getDataSource('default');
$table = $db->fullTableName(CAKE_SESSION_TABLE);
$db->execute("DELETE FROM " . $db->name($table) . " WHERE " . $db->name($table.'.expires') . " < ". $db->value(time()));
return true;
}
/**
* Helper method to initialize a session, based on Cake core settings.
*
* @return void
* @access private
*/
function __initSession() {
switch($this->security) {
case 'high':
$this->cookieLifeTime=0;
if (function_exists('ini_set')) {
ini_set('session.referer_check', $this->host);
}
break;
case 'medium':
$this->cookieLifeTime = 7 * 86400;
break;
case 'low':
default:
$this->cookieLifeTime = 788940000;
break;
}
switch(CAKE_SESSION_SAVE) {
case 'cake':
if (!isset($_SESSION)) {
if (function_exists('ini_set')) {
ini_set('session.use_trans_sid', 0);
ini_set('url_rewriter.tags', '');
ini_set('session.serialize_handler', 'php');
ini_set('session.use_cookies', 1);
ini_set('session.name', CAKE_SESSION_COOKIE);
ini_set('session.cookie_lifetime', $this->cookieLifeTime);
ini_set('session.cookie_path', $this->path);
ini_set('session.gc_probability', 1);
ini_set('session.auto_start', 0);
ini_set('session.save_path', TMP . 'sessions');
}
}
break;
case 'database':
if (!isset($_SESSION)) {
if (function_exists('ini_set')) {
ini_set('session.use_trans_sid', 0);
ini_set('url_rewriter.tags', '');
ini_set('session.save_handler', 'user');
ini_set('session.serialize_handler', 'php');
ini_set('session.use_cookies', 1);
ini_set('session.name', CAKE_SESSION_COOKIE);
ini_set('session.cookie_lifetime', $this->cookieLifeTime);
ini_set('session.cookie_path', $this->path);
ini_set('session.gc_probability', 1);
ini_set('session.auto_start', 0);
}
}
session_set_save_handler(array('CakeSession','__open'),
array('CakeSession', '__close'),
array('CakeSession', '__read'),
array('CakeSession', '__write'),
array('CakeSession', '__destroy'),
array('CakeSession', '__gc'));
break;
case 'php':
if (!isset($_SESSION)) {
if (function_exists('ini_set')) {
ini_set('session.use_trans_sid', 0);
ini_set('session.name', CAKE_SESSION_COOKIE);
ini_set('session.cookie_lifetime', $this->cookieLifeTime);
ini_set('session.cookie_path', $this->path);
ini_set('session.gc_probability', 1);
}
}
break;
default:
if (!isset($_SESSION)) {
$config = CONFIGS . CAKE_SESSION_SAVE . '.php';
if (is_file($config)) {
require_once ($config);
}
}
break;
}
}
/**
* Helper method to create a new session.
*
* @return void
* @access private
*
*/
function __checkValid() {
if ($this->readSessionVar("Config")) {
if ($this->_userAgent == $this->readSessionVar("Config.userAgent") && $this->time <= $this->readSessionVar("Config.time")) {
$this->writeSessionVar("Config.time", $this->sessionTime);
$this->valid = true;
} else {
$this->valid = false;
$this->__setError(1, "Session Highjacking Attempted !!!");
$this->destroyInvalid();
}
} else {
srand ((double)microtime() * 1000000);
$this->writeSessionVar('Config.rand', rand());
$this->writeSessionVar("Config.time", $this->sessionTime);
$this->writeSessionVar("Config.userAgent", $this->_userAgent);
$this->valid = true;
$this->__setError(1, "Session is valid");
}
}
/**
* Method called on open of a database
* sesson
*
* @return boolean
* @access private
*
*/
function __open() {
return true;
}
/**
* Method used to read from a database
* session
*
* @param mixed $key The key of the value to read
* @return mixed The value of the key or false if it does not exist
* @access private
*/
function __read($key) {
$db =& ConnectionManager::getDataSource('default');
$table = $db->fullTableName(CAKE_SESSION_TABLE, false);
$row = $db->query("SELECT " . $db->name($table.'.data') . " FROM " . $db->name($table) . " WHERE " . $db->name($table.'.id') . " = " . $db->value($key), false);
if ($row && !isset($row[0][$table]) && isset($row[0][0])) {
$table = 0;
}
if ($row && $row[0][$table]['data']) {
return $row[0][$table]['data'];
} else {
return false;
}
}
/**
* Helper method to restart a session.
*
* @return void
* @access private
*/
function __regenerateId() {
$oldSessionId = session_id();
$sessionpath = session_save_path();
if (empty($sessionpath)) {
$sessionpath = "/tmp";
}
if (isset($_COOKIE[session_name()])) {
setcookie(CAKE_SESSION_COOKIE, '', time() - 42000, $this->path);
}
session_regenerate_id();
$newSessid = session_id();
$file = $sessionpath . DS . "sess_$oldSessionId";
@unlink ($file);
@session_destroy ($oldSessionId);
if (function_exists('session_write_close')) {
session_write_close();
}
$this->__initSession();
session_id ($newSessid);
session_start();
}
/**
* Restarts this session.
*
* @return void
* @access public
*/
function renew() {
$this->__regenerateId();
}
/**
* Helper method to extract variable names from the session
* variable
*
* @param mixed $name Variable names as array or string.
* @return string The expression to eval to get the value or false
* @access private
*/
function __sessionVarNames($name) {
if (is_string($name)) {
if (strpos($name, ".")) {
$names = explode(".", $name);
} else {
$names = array($name);
}
$expression="\$_SESSION";
foreach($names as $item) {
$expression .= is_numeric($item) ? "[$item]" : "['$item']";
}
return $expression;
}
$this->__setError(3, "$name is not a string");
return false;
}
/**
* Helper method to set an internal error message.
*
* @param int $errorNumber Number of the error
* @param string $errorMessage Description of the error
* @return void
* @access private
*/
function __setError($errorNumber, $errorMessage) {
if ($this->error === false) {
$this->error = array();
}
$this->error[$errorNumber] = $errorMessage;
$this->lastError = $errorNumber;
}
/**
* Helper function called on write for database
* sessions
*
* @param mixed $key The name of the var
* @param mixed $value The value of the var
* @return boolean
* @access private
*/
function __write($key, $value) {
$db =& ConnectionManager::getDataSource('default');
$table = $db->fullTableName(CAKE_SESSION_TABLE);
switch(CAKE_SECURITY) {
case 'high':
$factor = 10;
break;
case 'medium':
$factor = 100;
break;
case 'low':
$factor = 300;
break;
default:
$factor = 10;
break;
}
$expires = time() + CAKE_SESSION_TIMEOUT * $factor;
$row = $db->query("SELECT COUNT(id) AS count FROM " . $db->name($table) . " WHERE "
. $db->name('id') . " = "
. $db->value($key), false);
if ($row[0][0]['count'] > 0) {
$db->execute("UPDATE " . $db->name($table) . " SET " . $db->name('data') . " = "
. $db->value($value) . ", " . $db->name('expires') . " = "
. $db->value($expires) . " WHERE " . $db->name('id') . " = "
. $db->value($key));
} else {
$db->execute("INSERT INTO " . $db->name($table) . " (" . $db->name('data') . ","
. $db->name('expires') . "," . $db->name('id')
. ") VALUES (" . $db->value($value) . ", " . $db->value($expires) . ", "
. $db->value($key) . ")");
}
return true;
}
}
?>