xt_sctp - add SCTP header size to IP header offset

Hi, all.

xt_sctp module is not working on 2.6.16 when --chunk-types
option is used. I 
have test this running sctp_darn and the following iptables
options:

-A INPUT -p sctp --chunk-types any INIT -j DROP

And this is the kernel log output:

spt: 32822    dpt: 10105
Chunk num: 1  offset: 20      type: 128       length: 10105 
 flags: 36
skb->len: 92  offset: 10128
spt: 10105    dpt: 32822
Chunk num: 1  offset: 20      type: 39        length: 32822 
 flags: 79
skb->len: 284 offset: 32844
spt: 32822    dpt: 10105
Chunk num: 1  offset: 20      type: 128       length: 10105 
 flags: 36
...


Note that length is actually the local port, and offset must
be 32 (20 IPv4 
header + 12 SCTP header).

FYI, it works properly when --chunk-types is not used.


Regards.

Jorge. 

Jorge Matias Martin wrote:
> Hi, all.
> 
> xt_sctp module is not working on 2.6.16 when
--chunk-types option is used. I 
> have test this running sctp_darn and the following
iptables options:
> 
> -A INPUT -p sctp --chunk-types any INIT -j DROP
> 
> And this is the kernel log output:
> 
> spt: 32822    dpt: 10105
> Chunk num: 1  offset: 20      type: 128       length:
10105   flags: 36
> skb->len: 92  offset: 10128
> spt: 10105    dpt: 32822
> Chunk num: 1  offset: 20      type: 39        length:
32822   flags: 79
> skb->len: 284 offset: 32844
> spt: 32822    dpt: 10105
> Chunk num: 1  offset: 20      type: 128       length:
10105   flags: 36
> ...
> 
> 
> Note that length is actually the local port, and offset
must be 32 (20 IPv4 
> header + 12 SCTP header).
> 
> FYI, it works properly when --chunk-types is not used.

Looks good too me. Please add a Signed-off-by: line so I can
apply it. Thanks.