I am using the dojo toolkit to load files into a div, but I want to make the individual files only available if called through ajax and not available if called directly by the end user.

Basically the code in the pages will not work directly, and if they do then they could cause security problems because the main page handles the login and session data. I dont particuarly want to add a check login script to each of the pages that I call. The pages are in PHP.