IRC and ident with iptables

IRC and ident with iptables

[Alexander Salmin]

Hi.

I've set up my firewall so that it provides NAT for a small network.
That network has about 10 computers who are beeing used by diffrent
users. The problem is that I can't find a way to make the IRC-servers
that those computers are connected to recognize each computers
diffrent ident. So, what I would like to know is if there is a way to
make iptables recognize to whom it should portforward to, based of
what internal ip that is connecting. Can it be done? If not, is there
any identd-server for Linux 2.6 that you know could do this?

-Alexander

Re: IRC and ident with iptables

[/dev/rob0]

Alexander Salmin wrote:
> diffrent ident. So, what I would like to know is if there is a way to
> make iptables recognize to whom it should portforward to, based of
> what internal ip that is connecting. Can it be done? If not, is there

That would be tricky, but perhaps possible using some extension of 
connection tracking ... whoever makes a new connection to an ircd is 
going to get the next ident query from that IP.

> any identd-server for Linux 2.6 that you know could do this?

This is how I'd go about it. I've seen numerous identd's listed on 
freshmeat which claim to be able to do this. It wouldn't be that 
complicated, I think: look up the connection in ip_conntrack, query the 
appropriate internal identd, give that reply to the external client.
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RE: IRC and ident with iptables

[Piszcz, Justin]

Yes, oidentd.

-----Original Message-----
From: netfilter-bounces@lists.netfilter.org
[mailto:netfilter-bounces@lists.netfilter.org] On Behalf Of /dev/rob0
Sent: Sunday, June 05, 2005 10:46 AM
To: Alexander Salmin
Cc: netfilter@lists.netfilter.org
Subject: Re: IRC and ident with iptables

Alexander Salmin wrote:
> diffrent ident. So, what I would like to know is if there is a way to
> make iptables recognize to whom it should portforward to, based of
> what internal ip that is connecting. Can it be done? If not, is there

That would be tricky, but perhaps possible using some extension of 
connection tracking ... whoever makes a new connection to an ircd is 
going to get the next ident query from that IP.

> any identd-server for Linux 2.6 that you know could do this?

This is how I'd go about it. I've seen numerous identd's listed on 
freshmeat which claim to be able to do this. It wouldn't be that 
complicated, I think: look up the connection in ip_conntrack, query the 
appropriate internal identd, give that reply to the external client.
-- 
     mail to this address is discarded unless "/dev/rob0"
     or "not-spam" is in Subject: header