MVC authentication - it's own model?

I have a social network-esque site with a nice User model that seems to be covering all my bases right now.

I am reworking the code from spaghetti and want to find the best-practice solution for logging in / registering a user. Here are my options (I think):

1. Create a separate Auth class (model?) that simply searches for a record of a user and returns a new User object if found.

2. Add "login" functionality to the User class that will allow me to log my user in as any User object that I'd like.

开发者_如何转开发

Please let me know the cleanest way to go about this, as I am new to good coding practices (admittedly)

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Just do it separately in such a manner that you can extend the class later to do stuff like FB, OAuth, OpenID login, etc.