From: Brad Campbell <lists2009@fnarfbargle.com>
To: Dale Mellor <dale@rdmp.org>, Payam Chychi <pchychi@gmail.com>
Cc: Leonardo Rodrigues <leolistas@solutti.com.br>, netfilter@vger.kernel.org
Subject: Re: How to stop kernel TCP responses on a port
Date: Mon, 08 Sep 2014 11:11:11 +0800 [thread overview]
Message-ID: <540D1E4F.4000704@fnarfbargle.com> (raw)
In-Reply-To: <1409895712.16431.7.camel@l3>
On 05/09/14 13:41, Dale Mellor wrote:
>
> Anyway, the point is I don't want the syn-ack to come from the ground,
> but the Linux kernel insists on sending it. That's what I want to
> filter out, or otherwise stop.
The kernel only does that if there is a piece of application code that
is bound to that socket.
> In case I haven't been clear, the PC is the gateway to the spacecraft;
> effectively, it _is_ the proxy. When a telnet client (on the ground)
> connects to the gateway (on the ground), the gateway is responding to
> the SYN when I don't want it to.
Ok, so the ground station PC is acting as a proxy and you don't want
that. You want it to *route* the IP packets rather than be an
application level proxy.
So at the moment you are connecting to a socket that is bound in the
ground station PC. There is a piece of code there than binds and then
accepts the connection. Stop doing that and have iptables forward/nat
the packets instead.
If all that is incorrect, then you have not provided anywhere enough
information on the how's and why's.
next prev parent reply other threads:[~2014-09-08 3:11 UTC|newest]
Thread overview: 6+ messages / expand[flat|nested] mbox.gz Atom feed top
2014-09-04 15:17 How to stop kernel TCP responses on a port Dale Mellor
2014-09-04 16:16 ` Leonardo Rodrigues
2014-09-05 4:27 ` Dale Mellor
[not found] ` <CBD8736BE6044AE0B06076D69855AF85@gmail.com>
2014-09-05 5:41 ` Dale Mellor
2014-09-08 3:11 ` Brad Campbell [this message]
2014-09-09 13:49 ` Dale Mellor
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