Re: slirp: Can I get IPv6-only DHCP working?

From: Samuel Thibault <samuel.thibault@gnu.org>
To: Peter Delevoryas <peter@pjd.dev>
Cc: qemu-arm@nongnu.org, qemu-devel@nongnu.org, clg@kaod.org,
	garnermic@fb.com, patrick@stwcx.xyz, zhdaniel@fb.com
Subject: Re: slirp: Can I get IPv6-only DHCP working?
Date: Fri, 26 Aug 2022 01:20:13 +0200	[thread overview]
Message-ID: <20220825232013.43g4iieyqxrckkna@begin> (raw)
In-Reply-To: <YwgCjqC90KhDKUnr@pdel-fedora-MJ0HJWH9>

Peter Delevoryas, le jeu. 25 août 2022 16:15:26 -0700, a ecrit:
> On Fri, Aug 26, 2022 at 12:56:10AM +0200, Samuel Thibault wrote:
> > Peter Delevoryas, le jeu. 25 août 2022 15:38:53 -0700, a ecrit:
> > > It seems like there's support for an IPv6 dns proxy, and there's literally a
> > > file called "dhcpv6.c" in slirp, but it has a comment saying it only supports
> > > whatever is necessary for TFTP network boot I guess.
> > 
> > For which DNS support is welcome :)
> > 
> > > Maybe there's no support then?
> > 
> > It seems there is:
> > 
> >     if (ri.want_dns) {
> >         *resp++ = OPTION_DNS_SERVERS >> 8; /* option-code high byte */
> >         *resp++ = OPTION_DNS_SERVERS; /* option-code low byte */
> >         *resp++ = 0; /* option-len high byte */
> >         *resp++ = 16; /* option-len low byte */
> >         memcpy(resp, &slirp->vnameserver_addr6, 16);
> >         resp += 16;
> >     }
> 
> Well, that's great, but actually I just care about whether slirp supports DHCPv6
> address requests. Sorry if I didn't explain that properly.

Ah. It doesn't seem to indeed.

> since the DHCPv6 hook "dhcpv6_input" is already there, maybe I can
> just get something going through there?

Probably.

Samuel