From mboxrd@z Thu Jan  1 00:00:00 1970
From: Patrick McHardy <kaber@trash.net>
Subject: Re: MASQUERADE + DHCP problem
Date: Mon, 12 Sep 2005 01:57:22 +0200
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Cc: Harald Welte <laforge@netfilter.org>,
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To: Rusty Russell <rusty@rustcorp.com.au>
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Rusty Russell wrote:
> On Sun, 2005-09-11 at 17:07 +0200, Patrick McHardy wrote:
> 
>>2) Add a special hack to masquerade to handle DHCP while no
>>   local address exists by looking at the port and src/dst
>>   address. Incredibly ugly and wrong :)
> 
> 
> If IP src is 0.0.0.0, let it through untouched.  Those packets are
> presumably not supposed to be masqueraded, so it's the Right Think
> AFAICT.
> 
> Will that fix DHCP?

Absolutely. Since these packets never get routed, the only possibility
when they can occur is when a local raw socket with IP_HDRINCL chooses
a source address of 0. In that case it definitely seems right to leave
the packet alone.

Thanks!

Patrick