Tracking IP address of logins

I have a requirement that I need to track what IP address the user logged in
from. Is there any hooks to the login process that I can use to get and
record this information in my own database?

I was thinking if no hooks exists that I would create a portlet that went on
the first page that would update this information. Setting it to only be
visible for logged in users should make it only get called after I know who
the user is. Using the session Id and the username combination would make
sure I only created the log entry once in my database.

How do I get the user's IP address and name from the portlets doView method?

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Michael