Re: [Qemu-discuss] "-net user,guestfwd" protocol issue

[Denis Buzdalov]

Let me answer myself. I've found a workaround.

> According to documentation and experiments, guestfwd does not support
> UDP unlike its brother hostfwd. Does anyone know whether this is
> intentional (e.g. there are some difficulties in implementation) or
> this feature wasn't relevant and thus not implemented yet?

Since code that manages "guestfwd" option doesn't do anything with the
protocol itself, it's actually possible to forward UDP datagrams using
udp chardev.

I.e. if I want to write something like

-net user,guestfwd=udp:10.0.2.1:8000-127.0.0.1:800

which is not possible since UDP is not supported protocol for guestfwd,
I can do the same thing using the following parameters:

-chardev udp,id=m8,host=127.0.0.1,port=800 \
-net user,guestfwd=:10.0.2.1:8000-chardev:m8

At this configuration any guest's UDP datagram to 10.0.2.1:8000 is
forwarded as a datagram to 127.0.0.1:800 of the host (the behaviour I
wanted originally).

--
Denis Buzdalov