Forms Authentication Provider

Folks,


Please suggest (with an example if u can) how to achieve this scenario below:
Basic Forms Authentication allows me to authenticate the User from Login Page to Home Page. And during redirecting to home page, I am sending a xml request to datalayer for userToken and I receive the response containing UserToken after user is validated.
Now, my concern is that, how do I implement this Custom Forms authentication that would allow me send the xml UserToken Request along with the UserCredentials to the Datalayer? So, that user once get forms authenticated, UT response is sent back to UI


Thanks,

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