Server should respond over same socker UDP socket.

[zbleness]

When running in docker (--net=bridge) on Ubuntu 22.04 we hit a problem where the TFTP responses were not routed properly. After some investigation we concluded that the response got lost because it was coming from a different (random) host:port.

The patch in question re-uses the server socket for the UDP response so that reverse NAT treversal is possible in stricter network topologies.

[sirMackk]

Hi @zbleness , thanks for the PR and sorry for the delay. I'll look this over next week and go about merging/releasing :).

[zbleness]

I forgot about this patch as well @sirMackk . Even though it looked promising at start we could not get our e2e tests to work with py3tftp so we ended up switching to ptftplib. I guess what I'm trying to say is that we are not sure whether this patch improves your project or not as we did not follow it through. So please be careful before merging.