Re: [iptables PATCH 04/23] libxtables: xtoptions: Treat NFPROTO_BRIDGE as IPv4

[Phil Sutter <phil@nwl.cc>]

On Wed, Dec 20, 2023 at 08:20:10PM +0100, Jan Engelhardt wrote:
> 
> On Wednesday 2023-12-20 17:06, Phil Sutter wrote:
> 
> >When parsing for XTTYPE_HOST(MASK), the return value of afinfo_family()
> >is used to indicate the expected address family.
> >
> >Make guided option parser expect IPv4 by default for ebtables as this is
> >the more common case.
> 
> ebtables is about Ethernet addresses mostly,
> and ebt_ip6 and ebt_ip have the same priority really.

That's right, but there's also libebt_arp which expects IPv4 address
in --arp-ip-src and --arp-ip-dst options.

I was a bit undecided about this solution because libebt_ip6's
workaround is fugly:

| xtables_set_nfproto(NFPROTO_IPV6);
| xtables_option_parse(cb);
| xtables_set_nfproto(NFPROTO_BRIDGE);

OTOH introducing XTTYPE_HOST{,MASK}{4,6} to force the expected address
family despite afinfo->family value seemed over-engineering given the
single user I had to cover after treating NFPROTO_BRIDGE as IPv4 by
default.

Cheers, Phil