A Solution by Dave Smith - PHP Ghost Crypt package blog

By Nick Daniels

<email contact>

Here is my solution for a private hash

file: ghosthash.class.php

<?php
class ghostHash
{
public static function returnHash($publicKey){
$privateKey = 'addalittlepepper';
return md5($privateKey.$publicKey);
}
}


Change the $pepper variable to your own private key

1a) for max protection place the ghosthash.class.php file in a private folder on the server.

1b) for less protection if you don't have access to non web accessible folders, place it in the document root

2a) set the auto_prepend_file setting in php.ini to point to this file. example, auto_prepend_file = '/path/to/ghosthash.class.php'

3a) restart your server

2b) if you don't have access to the php.ini file and are not able to restart the server, set the auto_prepend_file setting in .htaccess by adding this line... php_value auto_prepend_file /path/to/ghosthash.class.php

3b) if your host does not allow you to change ini settings in .htaccess, contact them for their specific requirements, like a user defined ini file, etc...

Once this is set up properly, you can get a private hash using a public key by calling the static method...

ghosthash::returnHash(string publicKey);

encrypting using this ghost hash will always ensure that the file will have a valid public key and only on a system where the private hash is valid. It will now be safe to show the public key in the self executing encrypted file.

Dave