CodeIgniter Authentication System that allows 3rd party auth?
If you want a CI OAuth2 implementation you can use this library which is both client and server:
Otherwise for OpenID use this library:
I was also looking for something like this just a month ago, but unsuccessfully. The only framework that has it all integrated in a simple way that I have seen is meteor, but it is not a PHP framework.
I had to do it myself by wrapping different PHP libraries in CI libraries. The source code is on github: CI Twitter and Who You Meet (a live web app), that has Twitter, LinkedIn and Facebook authentication and also a lot of local authentication logic with email verification and password recovery.
I know it can be considered a shameless promotion, but I hope it is useful. Although it is not exactly what you are looking for, it seems to be rather stable, so feel free to re-use it.
Maybe you will have time to extract all this logic in a standalone library (like I did for twitter) for other folks to use :)