Is there a module orso for a IP Lock ?

I want a private section. Like a private shop. I can do like this; I make a special group. and allow THAT group to see the shop. And some special users i put in the group so they can see the shop. They are allowed.

But...

I want there IP's locked...cause if they want they can login to there account from elsewhere and see the shop also. I dont want that. Can someone please help me out a bit with this problem.