On Fri, Oct 31, 2008 at 12:05:28PM -0400, Lowell Gilbert wrote: > Jeremy Chadwick <[EMAIL PROTECTED]> writes: > > > On Thu, Oct 30, 2008 at 06:34:31PM -0500, Jack Barnett wrote: > >> > >> Ok, I had some progress with this last night. Basically what I do is: > >> > >> in natd - redirect_port 1000 to 10000 to the internal windows box. > >> set ipfw to "open" file wall. > >> > >> Obviously this isn't prefect - but gives some idea of what's going on. > >> > >> What I'd like to do, is a) keep the nat redirects since that works > >> pretty well. > >> b) in ipfw, ONLY allow data back on these ports IF the windows box has > >> established the connection out first then deny everything else. > > > > This is called "port triggering" in the residential router world. I > > don't know how to do this on FreeBSD. > > Stateful rules are the only way to do it. > In fact, this is the main purpose of stateful rules.
Read this part of the thread, where I outline protocol flow (based on what the OP has stated about the protocol, which so far appears to be accurate): http://lists.freebsd.org/pipermail/freebsd-questions/2008-October/thread.html Stateful rules will not solve this problem. The OP wants a feature that tells ipfw or pf "after the TCP handshake has completed, dynamically add a port forward for port X on interface Y to machine A on port Z; when the TCP session is FIN'd cleanly, or extinguishes, dynamically remove that port forward". -- | Jeremy Chadwick jdc at parodius.com | | Parodius Networking http://www.parodius.com/ | | UNIX Systems Administrator Mountain View, CA, USA | | Making life hard for others since 1977. PGP: 4BD6C0CB | _______________________________________________ email@example.com mailing list http://lists.freebsd.org/mailman/listinfo/freebsd-questions To unsubscribe, send any mail to "[EMAIL PROTECTED]"