From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-2.3 required=3.0 tests=DKIM_SIGNED,DKIM_VALID, DKIM_VALID_AU,FREEMAIL_FORGED_FROMDOMAIN,FREEMAIL_FROM, HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS, USER_AGENT_SANE_1 autolearn=no autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id BC6B9C3A5A2 for ; Tue, 3 Sep 2019 15:59:25 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 8B50522CF8 for ; Tue, 3 Sep 2019 15:59:25 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=gmail.com header.i=@gmail.com header.b="ai21DDIp" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1729053AbfICP7Y (ORCPT ); Tue, 3 Sep 2019 11:59:24 -0400 Received: from mail-wr1-f66.google.com ([209.85.221.66]:44549 "EHLO mail-wr1-f66.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1727069AbfICP7Y (ORCPT ); Tue, 3 Sep 2019 11:59:24 -0400 Received: by mail-wr1-f66.google.com with SMTP id 30so7124029wrk.11 for ; Tue, 03 Sep 2019 08:59:22 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20161025; h=subject:to:cc:references:from:message-id:date:user-agent :mime-version:in-reply-to:content-language:content-transfer-encoding; bh=doEXvD9ohBmcCvnOgHklhHYhj4U2HVc9bRnTXyDOsj8=; b=ai21DDIpqlEq0sdGgELLie+7u2+wXcNmNkVMrW2wOo0q7YJysCFRwiDMeW8mquI8K/ 4CMTPfCMVwoJ8NHfojJ7go5+Vs+bTI7RVOWapZ1XLYlzaa7yz9XR43VlRf/Tj7HBVoYz BIAsGVVmUCewybSESKx1Le6P4L5WirOtVyKPJoR7LOcITnNgun1MoWom5EkPsSVZWmUM LIfPkjtz2iAwJE0qYK1eCaaCLpeAX6nxdqlbks/EohxnQcYbRROpQUjJu2bJ+K5FXlEW dPM1hL7AAanAg72q7dnODBXSMiP3NdZhZNfCwqDbjw5jI7UtmhQQXVsSvkt6MxN4H54g dhsA== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:subject:to:cc:references:from:message-id:date :user-agent:mime-version:in-reply-to:content-language :content-transfer-encoding; bh=doEXvD9ohBmcCvnOgHklhHYhj4U2HVc9bRnTXyDOsj8=; b=ALC4VjMAsPQaSvRcbytpO6mDPj1fgKM74uxGj/rgCWx8JL0YqDrK2eLdjreeVyq/CR 4x68wO4OGapqjNNtrEdhlnJ5ZTshZNnQyAJ2TU2z1wuDU7Xdy2QE9LxkQDd9F2Spqzs+ xSJsL6pYVQ/8iYAVC6kz2m14qxgqxZspdEboWbw7BcM4EhUH1/4XDS0ZlVub/sdWld5A kVyvg/xHTqIUr8XQI6W3z8BxScgSjTvalvpgkM43aTbQnlXzOc+p7Fmkp67aByZZyanJ 79AVXjygg1if88P4f7Jcyf3g5YnWG8ZBONYakZ5yjb9JQestY7ESzqC1fb+5XJ3b43Ue 6WRw== X-Gm-Message-State: APjAAAW1mEXrKtTeO/Os7D2PjBiHTBe4uBjKzMj0dqyW8skfTven/rZw cEIZPut0Q3ivt61d22EYHvg= X-Google-Smtp-Source: APXvYqxPhiZap2ZdEQ5guDIB4FvgRxTN1VkVnI0Xz6tquSxKFR2Qwat0YlJpFuPCn36KUdVukLvF5w== X-Received: by 2002:adf:fe07:: with SMTP id n7mr28846905wrr.90.1567526362304; Tue, 03 Sep 2019 08:59:22 -0700 (PDT) Received: from [192.168.8.147] (83.173.185.81.rev.sfr.net. [81.185.173.83]) by smtp.gmail.com with ESMTPSA id v4sm19525041wrg.56.2019.09.03.08.59.21 (version=TLS1_3 cipher=TLS_AES_128_GCM_SHA256 bits=128/128); Tue, 03 Sep 2019 08:59:21 -0700 (PDT) Subject: Re: [PATCH] Clock-independent TCP ISN generation To: Cyrus Sh , davem@davemloft.net Cc: shiraz.saleem@intel.com, jgg@ziepe.ca, arnd@arndb.de, netdev@vger.kernel.org, sirus@cs.utah.edu References: <70c41960-6d14-3943-31ca-75598ad3d2d7@gmail.com> From: Eric Dumazet Message-ID: <2cbd5a8f-f120-a7df-83a3-923f33ca0a10@gmail.com> Date: Tue, 3 Sep 2019 17:59:20 +0200 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:60.0) Gecko/20100101 Thunderbird/60.8.0 MIME-Version: 1.0 In-Reply-To: Content-Type: text/plain; charset=utf-8 Content-Language: en-US Content-Transfer-Encoding: 7bit Sender: netdev-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: netdev@vger.kernel.org On 9/3/19 5:39 PM, Cyrus Sh wrote: > > > On 9/3/19 1:41 AM, Eric Dumazet wrote: >> Clock skew seems quite secondary. Some firewall rules should prevent this kind of attacks ? > > Can you provide any reference to somewhere that explains these firewall rules > and how to exactly use them to prevent this specific type of attack? > You could add a random delay to all SYN packets, if you believe your host has clock skews.