Re: portfw on iptables 2.4 kernel problem.

["louie miranda" <lmiranda@chikka.com>]

Hi, thanks for all your replies, etc. But my problem is not yet solved. I
dont know why?!
Can someone give me how did they did it?



--
thanks,
louie miranda


----- Original Message -----
From: "Jozsef Kadlecsik" <kadlec@blackhole.kfki.hu>
To: "Raymond Leach" <raymondl@knowledgefactory.co.za>
Cc: <rsterenborg@xs4all.nl>; "'Paulo Andre'" <pandre@darkstar.nom.za>;
"'louie miranda'" <lmiranda@chikka.com>; "'netfilter'"
<netfilter@lists.netfilter.org>
Sent: Tuesday, December 10, 2002 7:22 PM
Subject: RE: portfw on iptables 2.4 kernel problem.


> On 10 Dec 2002, Raymond Leach wrote:
>
> > Yes, you do. Port 20 (and/or any other) connections after the control
> > connection are not 'RELATED, ESTABLISHED' to the control connection.
> > They are new connections either from the client to the server or vice
> > versa. You therefore need seperate rules for them.
>
> If we are speaking about the data channels of the supported protocols
> (FTP, IRC and all the other protocols from p-o-m), then this is absolutely
> false.
>
> > Remember connection tracking happens at a pakcet level, i.e all states
> > relate to packets of a connection, not per protocol.
>
> In the case of the supported protocols with additional channels, again,
> untrue. Please do no spread false info! Why would then the RELATED state
> exist?
>
> > > However, I'm not sure if it's better to split them up into 2 rules :
> > > iptables -A FORWARD -i eth0 -o eth1 -p tcp --dport 21 -m state --state
> > > NEW -j ACCEPT
> > > iptables -A FORWARD -i eth0 -o eth1 -m state --state
ESTABLISHED,RELATED
> > > -j ACCEPT
>
> Because the destination port of the data channels cannot be port 21,
> therefore you must use two rules. And because you specify the
> incoming/outgoing interfaces, you need a third rule for the reply packets
> as well.
>
> Regards,
> Jozsef
> -
> E-mail  : kadlec@blackhole.kfki.hu, kadlec@sunserv.kfki.hu
> PGP key : http://www.kfki.hu/~kadlec/pgp_public_key.txt
> Address : KFKI Research Institute for Particle and Nuclear Physics
>           H-1525 Budapest 114, POB. 49, Hungary
>
>
>