I happen to live inside a large LAN connected to the outside Internet. The majority of the lan's inhabitants only have unroutable IPs, though I do have a proper valid fixed one and can accept incoming connections from the outside. There's a lot of hosts inside the LAN, and a good many of them share files through the gnutella protocol.

I would probably share some too, but there's a catch: All downloads from outside the network are billed rather steeply, so I would rather prevent any direct connections to hosts which are /NOT/ in several specific ranges of addresses, or at the very least, any /inbound/ traffic from them. Outbound traffic is okay.

Is there a way to do this with mutella?