How to configure npf to restrict nfs to localhost

[Mayuresh <mayuresh%acm.org@localhost>]

Looking to share host FS with a qemu guest using NFS.

Do not want to expose the NFS ports to outside world. Firstly, what all
ports are in question - is it 111, 1000 and 2049 (rpc,mount,nfs
respectively) or is there anything else involved?

Any hints for how to block these ports for outside world and keep open for
localhost?

Mayuresh