Re: [PATCH 1/3] netfilter: arptables: add mcmangle target

[Pablo Neira Ayuso <pablo@netfilter.org>]

Pablo Neira Ayuso wrote:
> Patrick McHardy wrote:
>> Great name. Took me a bit to realize the connection to "multicast" :)
> 
> I thought about mcnugget target, but it seems to be already copyrighted ;)
> 
>> Continuing the idea of a generic ARP address mangling target,
>> this would have to be done in userspace using SIOCADDMULTI.
>>
>> I would also prefer that approach because the multicast mangling
>> seems a bit like a hack which only works when the requesting
>> host accepts a multicast MAC address in the ARP reply.
> 
> Indeed, I didn't know about SIOCADDMULTI, great. I'll do it like you
> have proposed. Thanks.

Hey, just to let you know ;). The 'ip' tool already allows adding static
multicast MAC addresses via SIOCADDMULTI. The following commands do the
trick:

ip maddr add 01:00:5e:00:01:01 dev eth1
arptables -I OUTPUT -o eth1 --h-length 6 \
-j mangle --mangle-mac-s 01:00:5e:00:01:01
arptables -I INPUT -i eth1 --h-length 6 --destination-mac \
01:00:5e:00:01:01 -j mangle --mangle-mac-d $REAL_HWADDR1

Still the PKTTYPE iptables target that I posted is needed to make TCP
and friends work in a devide that uses a multicast MAC.

-- 
"Los honestos son inadaptados sociales" -- Les Luthiers