From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mail-ed1-f44.google.com (mail-ed1-f44.google.com [209.85.208.44]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id A4D6F2C9F for ; Fri, 22 Oct 2021 11:25:32 +0000 (UTC) Received: by mail-ed1-f44.google.com with SMTP id g10so263894edj.1 for ; Fri, 22 Oct 2021 04:25:32 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=tessares-net.20210112.gappssmtp.com; s=20210112; h=message-id:date:mime-version:user-agent:subject:content-language:to :cc:references:from:in-reply-to:content-transfer-encoding; bh=evOW/91lHPzDl/JMN2MfEH/jLbeBJxzFqKTK/uNFH4s=; b=BJf+SNqV2tvYGjHnCNNX3PZxBr8P+Jnw9XhgmHVS1OplWmTAQxLXEz/xMWT1oLgjLu 8R3CDEdoRF7wzJvjsJ/lLS/IKjphLzNiigdBsStO1TlWGL6plZwTJ3gtkeJbRW7Obzau HcmSHNDbZ3BBBRQdxPDjxV07zi5V79oXIqrJLoIiM2pKvPE0nPELd03t8zlfDVRphqTI UmILEMO+qRs42Puv3ziNaNvplWgr8fgMX6weCwl4LwuRa+yFTxQYziysZbn3e47u0JaT YDPI37OeDVFLRmyu9MMduOOXZVaFWnGeW1xZfFLtWu/SFiUbDXhsgFdjA15DXphZ0Ufe vr3A== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20210112; h=x-gm-message-state:message-id:date:mime-version:user-agent:subject :content-language:to:cc:references:from:in-reply-to :content-transfer-encoding; bh=evOW/91lHPzDl/JMN2MfEH/jLbeBJxzFqKTK/uNFH4s=; b=HDFO/6T3zdADFeNXqEW1Q061aHo8sxn1CZ+7Xl9frmDsD2yp/5jDgFq5Z4zIw7wON6 T9OUbmXPmAwB8M+hJWwd7Ute/vgF+7f8YmFbnFQ7eNLI3oWBL9XI+6sSGJ5BLQJ1Bh2C VazKMU6arHX270qURnKVvqIkzH5WvrNn601Z/xcEk0KhPOq7VGu2sxy10rJlncOddO1w uWX104AQIWeYO965bKIO8TCjZYTmrPx66quW8ZiLaDDyN8iWUpc8fyE4wnUHJiAg7fxw QHSlAO4ObUL7ZMRT/kLPdbREIAVVfz1J0lajPZaisnkU9VtAPe6tJ7XA8Swq+q6fhqQK i7GQ== X-Gm-Message-State: AOAM531vJo+Jjjgfi8KcF68O5Bfnn+3CeHxhZgU1s+row2l55qpWn2Cs TbVcyOIF0NAgatOZrLXfAV7MYfu+6Oo= X-Google-Smtp-Source: ABdhPJwPacl+qC7fOoP9UkYmvkOgDC9V29xOnWvOvMAftiHqI97LWiqbAc1Yi3TTb025M3LfyojynA== X-Received: by 2002:a05:6402:1390:: with SMTP id b16mr15898953edv.166.1634901930554; Fri, 22 Oct 2021 04:25:30 -0700 (PDT) Received: from [192.168.178.46] ([213.211.156.121]) by smtp.gmail.com with ESMTPSA id n23sm4362625edw.75.2021.10.22.04.25.29 (version=TLS1_3 cipher=TLS_AES_128_GCM_SHA256 bits=128/128); Fri, 22 Oct 2021 04:25:29 -0700 (PDT) Message-ID: <304c130a-41ea-8e0a-4d88-d22edb14ef9f@tessares.net> Date: Fri, 22 Oct 2021 13:25:28 +0200 Precedence: bulk X-Mailing-List: mptcp@lists.linux.dev List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:91.0) Gecko/20100101 Thunderbird/91.1.2 Subject: Re: [PATCH mptcp-next v7 8/8] DO-NOT-MERGE: mptcp: mp_fail test Content-Language: en-GB To: Geliang Tang , Davide Caratti Cc: Geliang Tang , Mat Martineau , MPTCP Upstream References: <2e9a15d32cd39483dd1e18174d6c73b33e0566b5.1634531093.git.geliang.tang@suse.com> <7e1c37e5-a636-68f1-aaa-329f951b2c55@linux.intel.com> <8d7963f3-1983-0086-dcbe-16e950230f0a@tessares.net> From: Matthieu Baerts In-Reply-To: Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Hi Geliang, Davide, On 22/10/2021 09:37, Geliang Tang wrote: > Matthieu Baerts 于2021年10月21日周四 下午8:51写道： >> On 21/10/2021 11:19, Davide Caratti wrote: >>> On Wed, Oct 20, 2021 at 04:49:35PM +0200, Matthieu Baerts wrote: (...) >>>> The only thing is that netem will introduce errors at random positions, >>>> maybe in IP/TCP headers but it is maybe not an issue. If the TC filter >>>> command is enough, it might help to produce more controlled tests. >>> >>> maybe TC flower + action is even more accurate then netem: because it leaves >>> you the freedom to "corrupt" only packets after the 3WHS (or only the 3WHS, >>> depending on the match arguments of flower). >>> You can obtain the same randomization as netem by using TC "act_gact" random >>> feature ("CONFIG_GACT_PROB=y") >>> >>> # tc filter add dev vetha egress protocol ip prio 1001 flower \ >>> > ip_proto tcp \ >>> > tcp_flags 0x10/0xff \ <-- only the ACK BIT is set >>> > action pass random determ pipe 10 \ <-- 1 packet every 10 goes to pedit, others go out unmodified >>> > pedit munge offset 148 u32 invert pipe csum tcp <-- corrupt the payload and recompute checksum >> >> Good point! >> I don't know if Geliang wants to have all packets transporting data that >> are being corrupted or a random one out of X packets or only a specific one. > > I want to have only a specific packet to be corrupted, like sending 10 > unmodified packets, then sending 1 corrupted packet, then sending 10 > unmodified packets. How can I do this? I didn't find any man page about TC GAct, I guess we would need to look at that code to have a "statistic way" like you want. A workaround could be to insert the rule after the creation of the connection, no? In this case, you don't need "pass random determ pipe 10": all packets carrying data would be corrupted. Or maybe "one every 10 packets" is enough? Then you can remove the rule if you need to send unmodified packets but I don't think you need this, do you? Or maybe Davide has a better idea or knows how TC GAct works? :) Cheers, Matt -- Tessares | Belgium | Hybrid Access Solutions www.tessares.net