(unknown),

(unknown),

[Sohan Shetty]

Is  anyone aware if there an  NAT module for netfilter being developed
for SCTP protocol ?


I have searched the netfilter development tree source code and also
mailing list and so far I have not found the NAT module for SCTP . There
is SCTP conntrack module and packet match module. 

If anyone is aware and can point me to  some one who is already working
on this or has evaluated this it would be of great help.


SCTP is defined in [RFC 2960] Stewart, R., Xie, Q., Morneault, K.,
Sharp, C., Schwarzbauer, H., Taylor, T., Rytina, I., Kalla, M., Zhang,
L. and V. Paxson, "Stream Control Transmission Protocol", RFC 2960,
October 2000. 


Thanks and best regards
sohan

Re: SCTP NAT

[Patrick McHardy]

Sohan Shetty wrote:
> Is  anyone aware if there an  NAT module for netfilter being developed
> for SCTP protocol ?
> 
> 
> I have searched the netfilter development tree source code and also
> mailing list and so far I have not found the NAT module for SCTP . There
> is SCTP conntrack module and packet match module. 
> 
> If anyone is aware and can point me to  some one who is already working
> on this or has evaluated this it would be of great help.


I looked into this a few weeks ago, but multihoming is problematic
since the ports need to stay stable, so the vtag needs to be used
as key. Conntrack doesn't support this currently.

A further problem are checksum updates. There are multiple
different checksumming algorithms in use, with no way of
finding out which one is used currently, all require full
recalculation.