PHP

Verifying session info

unset($username);
 if (isset($_SESSION['login'])) { 
     list($c_username,$cookie_hash) = explode(',',$_SESSION['login']); 
     if (md5($c_username.$secret_word) == $cookie_hash) { 
        $username = $c_username; 
     }else{ 
        print "You have tampered with your session."; 
     } 
}