Re: xt_owner-xt_socket plans

[Laszlo Attila Toth <panther@balabit.hu>]

Jan Engelhardt írta:
> On Jan 21 2008 10:11, Laszlo Attila Toth wrote:
>> http://people.netfilter.org/hidden/tproxy/tproxy4-2.6.24-200710190050.tar.bz2
>>
> In the xt_socket code, I just noticed:
> 
> 	struct udphdr *hp;
> 	hp = skb_header_pointer(skb, ip_hdrlen(skb), sizeof(_hdr), &_hdr);
> 
> Does that mean xt_socket only receives UDP? Also, the header should always be
> available so that skb_header_pointer is not necessary.
> Where am I being misled?
> 

No, both tcp and udp packets are receiving.

Usage of udphdr is beacuse the first two members of the struct 
{udp,tcp}hdr types are the same, they are the source and destionation 
ports, and they are used as parameters of nf_tproxy_get_sock_v4 function:
          __be16  source;
          __be16  dest;

Either tcphdr or udphdr can be used, and the latter one is the simplier 
type.


-- 
Attila
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