Default action for http handler?

I'm working on setting up a site that controls 开发者_如何学Goaccess to a directory for downloads using an ihttpmodule. Since the files are all zip, exe, rar, and so on, the default handler isn't being applied and session state isn't available. So I've added a custom http handler for that directory that uses IRequiredSessionState so my session is now available in my module. However, I'm at a loss as to what to do with with the process request method in the handler. Is there any way to call the default action for process request? Since what I'm trying to do is serve downloads, is the closest I'm going to get going to be doing a context.Response.TrasmitFile()? At that point, is there even any point in having the http module, and just do my security check in the handler? Thanks!