From mboxrd@z Thu Jan  1 00:00:00 1970
From: Andi Kleen <ak@muc.de>
Subject: Re: Do you know the TCP stack? (127.x.x.x routing)
Date: 6 Mar 2005 22:30:47 +0100
Message-ID: <20050306213047.GA65970@muc.de>
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Cc: Zdenek Radouch <zdenek@rcn.com>, Martin Mares <mj@ucw.cz>,
	netdev@oss.sgi.com, linux-net@vger.kernel.org
Date: Sun, 6 Mar 2005 22:30:47 +0100
To: Thomas Graf <tgraf@suug.ch>
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Sender: linux-net-owner@vger.kernel.org
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On Sun, Mar 06, 2005 at 09:45:16PM +0100, Thomas Graf wrote:
> * Andi Kleen <m1y8d0mss2.fsf@muc.de> 2005-03-06 21:19
> > Zdenek Radouch <zdenek@rcn.com> writes:
> > >
> > > There is no doubt that the 127.x net is treated in a special
> > > way.  If I have to believe what I just learned, then the 127
> > 
> > It is. 127.* is hardcoded in the routing engine and e.g.
> > it won't accept outside packets with a loopback address.
> > 
> > Most likely it's enough to change the "LOOPBACK" macro to allow
> > parts of the Class A to be used for other purposes.
> 
> Yes, it will work around the martian route and arp checks but
> will probably break quite a few usersapce applications.

Unlikely. glibc has an own LOOPBACK() and all modern distributions
use separate kernel/user headers anyways.

-Andi