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From: Pascal Hambourg <pascal.mail@plouf.fr.eu.org>
To: Bill Hendrickson <wjhendrickson@gmail.com>
Cc: netfilter list <netfilter@vger.kernel.org>
Subject: Re: SSH Port Forwarding with iptables
Date: Fri, 02 Oct 2009 00:07:34 +0200	[thread overview]
Message-ID: <4AC52826.3030800@plouf.fr.eu.org> (raw)
In-Reply-To: <a0017e7e0910010824x697f1e82h57abe8df7ca68208@mail.gmail.com>

Bill Hendrickson a écrit :
>> In the FORWARD chain the destination port has already been changed by
>> the DNAT rule just like the destination address, so this rule must match
>> on destination port 22, not on the original destination port.
> 
> So you're saying it needs to be this?
> 
> $IPT -A FORWARD -p tcp -i $EXT_IFACE -o $INT_IFACE -d $SSH_HOST
> --dport 22 --sport 1024:65535 -m state --state NEW -j ACCEPT

Correct.

> For now, I've actually got it like this (which is working, but I
> should lock it down):
> 
> -A FORWARD -p tcp -m state --state NEW,RELATED,ESTABLISHED -j ACCEPT

This is much too permissive, it allows any connection through the router.

  reply	other threads:[~2009-10-01 22:07 UTC|newest]

Thread overview: 10+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2009-09-29 15:16 SSH Port Forwarding with iptables Bill Hendrickson
2009-09-29 16:14 ` Bill Hendrickson
2009-10-01 10:37   ` Pascal Hambourg
2009-10-01 15:24     ` Bill Hendrickson
2009-10-01 22:07       ` Pascal Hambourg [this message]
2009-10-01 16:26     ` Gáspár Lajos
2009-09-29 16:16 ` Gáspár Lajos
2009-09-29 16:41   ` Bill Hendrickson
2009-09-29 17:00     ` Gáspár Lajos
2009-09-29 17:12       ` Bill Hendrickson

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