[Scott MacVicar]

Simpliest way to do something like this is use

PHP Code:

if(!strstr("$_SERVER[PATH_TRANSLATED]", "$_SERVER[DOCUMENT_ROOT]")) {
die();
} 


If the document root path is not found in the script filename path then exit the script. This means the script would have to had been executed above the users document root, so if you have /home/username/public_html then the script would have had to be executed in any of these folders. You can add this to the top of config.php but I don't see a point personally.