CommunityAuth Login/Logout Hooks/Functions

I'm looking for the best way to implement the following...

I have CommunityAuth up and running, works great.

But I want to log/audit login/logout actions. I have a separate auditlog() function already written for this, but where is the best place call it from?

Inside the Auth_Model login_update() function for login?
Inside the Auth_Model logout() function for logout?

Thanks