How to set the Principal in an ASP.Net app

Question

I am writing a web app for a client. Users will have a one-time key that they will use to initially identify themselves to the app. Once the app verifies that the key is valid it will take them to a page where they can create a normal account to use for all subsequent logins. The create-account page should only be accessible after entering the key and shouldn't be accessible otherwise. I.e, it shouldn't be accessible to users logged in with a normal account. This is asp.net 3.0 using a custom membership provider.

My plan is to create a temporary account based on the key and authenticate the user with that account. This allows them access to the create-user page (which is protected with a location tag ) where they can create the formal account. I then authenticate them with their new account and delete the temporary account. The flow is: the user goes to a page where they enter the key. If the key is valid I create the temporary account, call FormsAuthentication.SetAuthCookie, and redirect to the create-account page. This all works, although it seems a little complicated.

The problem is that the create-user page is available to any authenticated user; I only want it available during the time between entering the key and creating the formal account. So I thought I'd create a special role for the temporary account and make the create-user page accessible only to that role and none other. I created my own Principal object with a special role and tried setting it when I authenticate the temporary account but I can't get that to work.

I'm really hoping I don't have to write a custom role provider just to do this.

How can I make this work? There's gotta be a simpler way!

Answer 1

Why not simply create the real account when they enter the key. Assign it some random name and then let them change the name and other details. Then you don't need the create user page, just the enter key page and an account details editing page. If you're concerned about getting the account details filled in, you could set it up (perhaps via code on a MasterPage) so that incomplete accounts always get redirected to the edit details page until the details are entered.

Or, you could have them enter the required details in addition to the key code on the enter key page and simply use those details when creating the account.

Answer 2

My advice would be to avoid the use of temporary accounts when validating the user. Instead, generate your own logic for validating the sign-up key. Then, at the head of the page, you can check whether the user is an authenticated user (SetAuthCookie has been called) and jump to a different page if this is true.

You may even be able to change the page access to forbid this page to authenticated users (I know you can disable accounts for unauthenticated users but I'm not sure if you can go the other direction).

The key, though, is to avoid relying on the membership provider when, in fact, the user is not yet a member!

Answer 3

Assign an "incomplete" role when authenticating against the temporary token, then restrict access to only that role... when the account is created, send them to a re-login page (terminating the authentication token). This will simplify your security model.