Jeff said the following on 10/13/05 00:50:
Howdy, Is it possible to rewrite packet payloads with pf, or failing that, some other tool on OpenBSD? I want to replace a series of four bytes with a different four bytes every time it occurs in the payload of an outgoing packet, but extensive Googling hasn't turned up anything. The reason for this is that I'm trying to get a braindead game that sends the IP of the interface on which it is running in the payload of a UDP packet to work. I know this functionality is available in some consumer-level "router in a box" products, but so far I have not been able to figure out how to do it with OpenBSD. Alternatively, if anyone knows of a Windows utility that performs the equivalent function, please speak up, as rewriting the packet before it hits my OpenBSD-based router would likely work just as well. Many thanks, Jeff
something like ftp-proxy, /usr/src/usr.sbin/ftp-proxy/, listening on a localhost connection, rdr the packets to that port, and using something like the ftp-proxy code, obtain the original destination socket, rewrite the packet as required and send it on to the proper destination.
