Re: [RFC] wireless, ipv4, ipv6: drop GTK-protected unicast IP packets

[Johannes Berg <johannes@sipsolutions.net>]

On Thu, 2013-11-21 at 06:24 -0800, Eric Dumazet wrote:
> On Thu, 2013-11-21 at 14:08 +0100, Johannes Berg wrote:
> > On Thu, 2013-11-21 at 14:05 +0100, Johannes Berg wrote:
> > 
> > > @@ -498,7 +500,8 @@ struct sk_buff {
> > >  	 * headers if needed
> > >  	 */
> > >  	__u8			encapsulation:1;
> > > -	/* 7/9 bit hole (depending on ndisc_nodetype presence) */
> > > +	__u8			drop_unicast:1;
> > 
> > The obvious question is here, and for IPv4/IPv6 - should the wireless
> > stack be responsible for doing this instead?
> 
> I don't really like the idea of reserving a bit for this in sk_buff,
> and propagate it in every cloning ...
> 
> Someone should replace __copy_skb_header() by a single memset(),
> because copying all these bits one by one is not really clever.
> 
> And then, adding a test in fast path (ip_rcv_finish()) is really not
> nice.

Yeah, that was a concern too. I'll do it entirely in the wireless stack
instead I guess. At least it'll be hidden away inside the if that
already does the group key check etc.

Thanks.

johannes