Problem with a specific php session class - php

Question

I am currently writing a PHP site for myself. Now I am trying to secure my site. Therefor I am using session. I don't want to write one for myself so I searched and found a wonderful example.
<?php
class SessionManager
{
static function sessionStart($name, $limit = 0, $path = '/', $domain = null, $secure = null)
{
// Set the cookie name
session_name($name . '_Session');
// Set SSL level
$https = isset($secure) ? $secure : isset($_SERVER['HTTPS']);
// Set session cookie options
session_set_cookie_params($limit, $path, $domain, $https, true);
session_start();
// Make sure the session hasn't expired, and destroy it if it has
if(self::validateSession())
{
// Check to see if the session is new or a hijacking attempt
if(!self::preventHijacking())
{
// Reset session data and regenerate id
$_SESSION = array();
$_SESSION['IPaddress'] = isset($_SERVER['HTTP_X_FORWARDED_FOR'])
? $_SERVER['HTTP_X_FORWARDED_FOR'] : $_SERVER['REMOTE_ADDR'];
$_SESSION['userAgent'] = $_SERVER['HTTP_USER_AGENT'];
self::regenerateSession();
// Give a 5% chance of the session id changing on any request
}elseif(rand(1, 100) <= 5){
self::regenerateSession();
}
}else{
$_SESSION = array();
session_destroy();
session_start();
}
}
/**
* This function regenerates a new ID and invalidates the old session. This should be called whenever permission
* levels for a user change.
*
*/
static function regenerateSession()
{
// If this session is obsolete it means there already is a new id
if(isset($_SESSION['OBSOLETE']) || $_SESSION['OBSOLETE'] == true)
return;
// Set current session to expire in 10 seconds
$_SESSION['OBSOLETE'] = true;
$_SESSION['EXPIRES'] = time() + 10;
// Create new session without destroying the old one
session_regenerate_id(false);
// Grab current session ID and close both sessions to allow other scripts to use them
$newSession = session_id();
session_write_close();
// Set session ID to the new one, and start it back up again
session_id($newSession);
session_start();
// Now we unset the obsolete and expiration values for the session we want to keep
unset($_SESSION['OBSOLETE']);
unset($_SESSION['EXPIRES']);
}
/**
* This function is used to see if a session has expired or not.
*
* #return bool
*/
static protected function validateSession()
{
if( isset($_SESSION['OBSOLETE']) && !isset($_SESSION['EXPIRES']) )
return false;
if(isset($_SESSION['EXPIRES']) && $_SESSION['EXPIRES'] < time())
return false;
return true;
}
/**
* This function checks to make sure a session exists and is coming from the proper host. On new visits and hacking
* attempts this function will return false.
*
* #return bool
*/
static protected function preventHijacking()
{
if(!isset($_SESSION['IPaddress']) || !isset($_SESSION['userAgent']))
return false;
if( $_SESSION['userAgent'] != $_SERVER['HTTP_USER_AGENT']
&& !( strpos($_SESSION['userAgent'], ÔTridentÕ) !== false
&& strpos($_SERVER['HTTP_USER_AGENT'], ÔTridentÕ) !== false))
{
return false;
}
$sessionIpSegment = substr($_SESSION['IPaddress'], 0, 7);
$remoteIpHeader = isset($_SERVER['HTTP_X_FORWARDED_FOR'])
? $_SERVER['HTTP_X_FORWARDED_FOR'] : $_SERVER['REMOTE_ADDR'];
$remoteIpSegment = substr($remoteIpHeader, 0, 7);
if($_SESSION['IPaddress'] != $remoteIpHeader
&& !(in_array($sessionIpSegment, $this->aolProxies) && in_array($remoteIpSegment, $this->aolProxies)))
{
return false;
}
if( $_SESSION['userAgent'] != $_SERVER['HTTP_USER_AGENT'])
return false;
return true;
}
}
?>
I am trying to call the function over:
include 'SessionSafe.php';
SessionManager::sessionStart('InstallationName');
i am testing the session with:
if (!isset($_SESSION['userid'])) {
header('Location: Login.php');
}
Before, I wrote a value in $_SESSION['userid'], but I have the problem that the session variable is empty...

Answer 1

//File1.php
include 'SessionSafe.php';
session_start();
SessionManager::sessionStart('InstallationName');
// file2.php
session_start();
if (!isset($_SESSION['userid'])) {
header('Location: Login.php');
}
You still have to use session start at the top of each php file.