'Access Denied!'

if (!defined('IS_INITPHP')) exit('Access Denied!');
defined('THINK_PATH') or exit('Access Denied!');
---------------------------------------------------------------------
 if(!isset($_SESSION['pin_permit']) || $_SESSION['pin_permit'] !== 'OK'){
    exit('Access Denied!');
}

http://blog.csdn.net/liuxinmingcode/article/details/8055431