From mboxrd@z Thu Jan  1 00:00:00 1970
From: David Miller <davem@redhat.com>
Subject: Re: updates to syncookies - timestamps not needed any more
 (freebsd)
Date: Fri, 12 Jul 2013 16:37:20 -0700 (PDT)
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From: Eric Dumazet <eric.dumazet@gmail.com>
Date: Fri, 12 Jul 2013 07:32:43 -0700

> Another quick hack would be to allow sack being generated by the client.
> 
> If we receive sackOK in SYN, then syncookie SYNACK could contain sackOK,
> if timestamps are not used.
> 
> Client would be allowed to use SACK in his ACK. Server would not
> generate SACK, but would process incoming SACK.
> 
> Not sure what could break ?

This seems quite clumsy and would result in being able to use SACK only
in one direction.

There has to be a better way.