Extending akrabat/rka-slim-session-middleware to bind session to IP address

Does anybody know what would need to be done in order to extend akrabat/rka-slim-session-middleware so that the session is bound to an IP address? Ie: I’d like the user to be logged out if/when their IP address changes.

Sorry for the basic question, I don’t have much experience writing session handling code and since this is important (security wise), I’d like to get it right.

I guess the simplest way to compare the current IP address to the IP address used when you created the session originally.

$session = new \RKA\Session();
if (empty($session->ip_address) {
    $session->ip_address = 'something';
} else if ($session->ip_address != 'something') {
    //redirect probably.

And right you are, why complicate matters when simple will do. I’m not sure why I made this out to be much more complicated while thinking about this. Thanks!