[Slirp] gvisor netstack as an alternative to slirp

[Marek Majkowski]

On Wed, Jan 29, 2020 at 1:33 PM Marc-André Lureau
<marcandre.lureau at gmail.com> wrote:
> On Tue, Jan 21, 2020 at 4:57 PM Marek Majkowski <majek04 at gmail.com> wrote:
> >
> > On Fri, Jan 3, 2020 at 9:00 AM Marc-André Lureau
> > <marcandre.lureau at gmail.com> wrote:
> > > This looks very promising!
> > I tried to get major feature parity with slirp4netns, just to prove if
> > gvisor/netstack is sufficient. It seems to be. This code supports
> > ipv6.
> >
>
> This is great and it seems to work like a charm!
>
> I have added a simple -fd option to allow to run with qemu -net
> socket,fd=: https://github.com/elmarco/slirpnetstack/tree/qemu (see
> qemu-run.py)

The code is missing the meat - the fd is ignored:
https://github.com/elmarco/slirpnetstack/commit/938dbe80b68c561abf51d3fdaec7bc41a3adab22

But I think I get the idea... Is anything else required to make qemu happy?

> It would be good to have a simple dhcp server built-in. TFTP/bootp
> would also be nice. That way, we could more easily replace libslirp
> for qemu. Do you think we should rely entirely on external processes
> for that or any idea what to use in go?

No thoughts here; I would be happy with DNS and dhcp inside this
project, but I don't think we should get tftp/bootp here. If possible
I would like some external process to handle these. But who knows -
maybe go makes it so trivial it's no-brainer.

> I have started a simple specification to allow external helper
> processes: https://gitlab.freedesktop.org/slirp/libslirp-rs/blob/master/src/bin/README.rst
> libvirt is learning to make use of it. But I could use help to better
> define this specification and make an official release.

Great!

> Maybe we can discuss it on IRC first #slirp on oftc?. Also are you
> coming to FOSDEM? (I am already in Brussels fwiw)

I'm skipping FOSDEM this year; I've been using the gvisor chat thingy:
https://gitter.im/gvisor/community

> cheers
>
>
> --
> Marc-André Lureau