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From: Andi Kleen <andi@firstfloor.org>
To: David =?utf-8?Q?T=C3=A4ht?= <dave.taht@gmail.com>
Subject: Re: Asserting ECN from userspace?
References: <4E8BF6B2.6030101@gmail.com>
Date: Thu, 06 Oct 2011 16:52:05 -0700
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David T=C3=A4ht <dave.taht@gmail.com> writes:
>
> And twiddling them, on a per stream basis, for a single packet, would
> seem to require something more robust than setsockopt/getsockopt
> (although that would work for udp streams)

With netfilter nf_queue you can construct a rule that passes packets
through user space and reinjects them.

I would suggest to just use that to modify the ECN bits.

I'm sure with reasonable google skills you can find some examples
how to do this on the web.

-Andi


--=20
ak@linux.intel.com -- Speaking for myself only