From owner-freebsd-net  Mon Jun  5 13: 6:41 2000
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Date: Mon, 05 Jun 2000 13:06:37 -0700
From: Shiva Shenoy <shiva@yagosys.com>
Reply-To: shiva@yagosys.com
Organization: Cabletron Systems, Inc.
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Subject: [Q]: Src address in the icmp_reflect()
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The following comment in icmp_reflect() in ip_icmp.c 
explains it all.

/*
 * If the incoming packet was addressed directly to us,
 * use dst as the src for the reply.  Otherwise (broadcast
 * or anonymous), use the address which corresponds
 * to the incoming interface.
 */

My question is: If the reply can take a different interface than
the packet that came in on, then the src address as seen in the 
icmp error packet is different from the interface from which it
is sourced.

If the packet is not addressed to us, then can we set the
source address to be the address of the outgoing interface? 
If so,this can be achieved by setting the ip->ip_src to INADDR_ANY.

Does anybody see a problem with this approach?

Thanks
Shiva Shenoy


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