I have a site that I'm trying to migrate into my Sitecore instance. The Sitecore instance has multiple sites. For the one site I'm trying to migrate over, there is a login page for external users to login. I'm validating this against an external database. This all works so far. My issue is that I need to prevent the external users from accessing certain pages without logging in(they should be redirected to the login page). The way that this was working when the site was outside of Sitecore was that there was forms authentication being done and when a page was trying to be accessed without the user being logged in the ReturnURL would be used to return the user to the proper page after login.
I'm not sure how to do this now that I have multiple sites inside of my sitecore instance.
Any suggestion?