On Wed, 4 Jan 2012, Hans Schillstrom wrote: > On Wednesday, January 04, 2012 19:05:10 Jozsef Kadlecsik wrote: > > On Wed, 4 Jan 2012, Pablo Neira Ayuso wrote: > > > > > On Wed, Jan 04, 2012 at 12:48:35PM +0100, Hans Schillstrom wrote: > > > > I like that idea, an "early" table at prio -500 with PREROUTING. > > > > There is also a need for a new flag "--allfrags" > > > > i.e. all fragments needs to be sorted out and sent to same dest for defrag. > > > > > > > > ex. > > > > iptables -t early -A PREROUTING -i eth0 --allfrags -j NOTRACK > > > > > > New tables add too much overhead. We have discussed this before with > > > Patrick. > > > > > > Since this still remains specific to your needs, I think you can > > > remove nf_conntrack module in your setup. > > > > > > I don't come with one sane setup that may want selectively defragment > > > some traffic yes and other not. > > > > > > Am I missing anything else? > > > > I agree. If you don't want defragmentation at all, then make sure you > > don't load the nf_conntrack module directly/indirectly. Conntrack doesn't > > work without defragmentation anyway. > > We are using LXC and it's only in the container that holds the external > interface that can't have defragmentation. > The problem is if it's loaded you have it in all namespaces :-( Conntrack is per net namespaces. You may have one container with conntrack enabled and another one without conntrack. Moreover, if you may receive fragments of the same packet at different interfaces in different blades, then you may receive different whole packets of the same flow at different interfaces/blades. But stateful firewalling relies on the assumption that all packets goes through of the firewall. Because it's not assured, conntrack may not run in the containers you denoted as FW LXC. Best regards, Jozsef - E-mail : kadlec@xxxxxxxxxxxxxxxxx, kadlecsik.jozsef@xxxxxxxxxxxxx PGP key : http://www.kfki.hu/~kadlec/pgp_public_key.txt Address : Wigner Research Centre for Physics, Hungarian Academy of Sciences H-1525 Budapest 114, POB. 49, Hungary -- To unsubscribe from this list: send the line "unsubscribe netfilter-devel" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
