An example security.php script.

<?php

switch ($_POST['form'])
{
    case 
'login':
        
$allowed = array();
        
$allowed[] = 'form';
        
$allowed[] = 'username';
        
$allowed[] = 'password';

        
$sent array_keys($_POST);

        if (
$allowed == $sent)
        {
            include 
'/inc/logic/process.inc';
        }

        break;
}

?>