I would like to write some code that would allow me to edit ip and arp
packets as they come off the wire and then pass them on to the kernel, and
edit them as the packets are about to be written to the wire.  I will also
be using ipnat and ipfilter.  My brief research tells me that I might want
something like the FreeBSD divert sockets functionality, but it doesn't seem
to carry over to NetBSD.  Does ipfilter offer some hooks like this?  Or will
I have to attempt mucking around in the kernel (which I haven't done
really)?

Any ideas as to the easiest way to do something like this would be greatly
appreciated.  Performance is not too much of a concern right now, in that
the load should not be very high.

Thanks!

Mike.