<?php
session_start();

if(!isset($_SESSION['name'])) die( 'ZOMFG H4XX0R!!11!ONE11!' );

$user = $_SESSION['name'];
$pass = $_SESSION['pass'];


$QUERY = "SELECT username, password FROM users WHERE username = '" . $user . "' AND password = '" . $pass . "'";

$EXEC = mysql_query( $QUERY );

if(mysql_num_rows($EXEC) != 1){

    unset($_SESSION['name'], $_SESSION['pass']);
   die( 'U bent niet ingelogd!');
}
?>