From mboxrd@z Thu Jan 1 00:00:00 1970 From: David Miller Subject: Re: [PATCH net-next v3 1/2] tcp: randomize tcp timestamp offsets for each connection Date: Fri, 02 Dec 2016 12:50:13 -0500 (EST) Message-ID: <20161202.125013.291984063589055137.davem@davemloft.net> References: <1480588327-2902-1-git-send-email-fw@strlen.de> Mime-Version: 1.0 Content-Type: Text/Plain; charset=us-ascii Content-Transfer-Encoding: 7bit Cc: netdev@vger.kernel.org To: fw@strlen.de Return-path: Received: from shards.monkeyblade.net ([184.105.139.130]:37476 "EHLO shards.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1755215AbcLBRuS (ORCPT ); Fri, 2 Dec 2016 12:50:18 -0500 In-Reply-To: <1480588327-2902-1-git-send-email-fw@strlen.de> Sender: netdev-owner@vger.kernel.org List-ID: From: Florian Westphal Date: Thu, 1 Dec 2016 11:32:06 +0100 > jiffies based timestamps allow for easy inference of number of devices > behind NAT translators and also makes tracking of hosts simpler. > > commit ceaa1fef65a7c2e ("tcp: adding a per-socket timestamp offset") > added the main infrastructure that is needed for per-connection ts > randomization, in particular writing/reading the on-wire tcp header > format takes the offset into account so rest of stack can use normal > tcp_time_stamp (jiffies). > > So only two items are left: > - add a tsoffset for request sockets > - extend the tcp isn generator to also return another 32bit number > in addition to the ISN. > > Re-use of ISN generator also means timestamps are still monotonically > increasing for same connection quadruple, i.e. PAWS will still work. > > Includes fixes from Eric Dumazet. > > Signed-off-by: Florian Westphal > Acked-by: Eric Dumazet > Acked-by: Yuchung Cheng Applied.