Signup & Payment script for freeradius server

We are currently setting up a wifi hotspot system that is using dd-wrt and chillispot, along with a radius server for authentication.

Freeradius is setup on a web server, and we now require a simple script that will allow users to select a wifi period (1hour, 1 day, 1 week), make payment via credit card (using Barclaycard EPDQ merchant), and for the radius server to then be updated and give access for the purchased time period.

After the time period purchased has expired, the radius server needs to stop access etc.

DDWRT, Chillispot and Freeradius are all setup, it is now just the payment script and connectivity of that script to radius that needs completing.