From patchwork Wed Jul 21 23:15:47 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Peilin Ye X-Patchwork-Id: 12392487 X-Patchwork-Delegate: kuba@kernel.org 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=-20.8 required=3.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,FREEMAIL_FORGED_FROMDOMAIN,FREEMAIL_FROM, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER,INCLUDES_PATCH, MAILING_LIST_MULTI,MENTIONS_GIT_HOSTING,SPF_HELO_NONE,SPF_PASS,USER_AGENT_GIT autolearn=ham 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 9A961C6377B for ; Wed, 21 Jul 2021 23:16:05 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 735ED60FF3 for ; Wed, 21 Jul 2021 23:16:05 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S230526AbhGUWf2 (ORCPT ); Wed, 21 Jul 2021 18:35:28 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:36572 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S230289AbhGUWf1 (ORCPT ); Wed, 21 Jul 2021 18:35:27 -0400 Received: from mail-qk1-x735.google.com (mail-qk1-x735.google.com [IPv6:2607:f8b0:4864:20::735]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 53859C061575; Wed, 21 Jul 2021 16:16:02 -0700 (PDT) Received: by mail-qk1-x735.google.com with SMTP id n10so3713670qke.12; Wed, 21 Jul 2021 16:16:02 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20161025; h=from:to:cc:subject:date:message-id:mime-version :content-transfer-encoding; bh=8kBHltz3fpi5tJOBHoxxMlZNZl2yFO4paDm36raK100=; b=J1AIz/EIQ87onxU71lAQ7/9TBEUOW4aEBpScIqH9TibBu7A3/rNhvMuU0nX5lxUfG/ 4k9TzQC12UEOFGm6p3SZsZenae9URnES5GwGWmeRK1PxIN+e8KFg4v02R7IjPcoO4/YI 2ec9XH1NQ9cTG4OajtQdjUeFTAQZWiFXzdyUdGVr2NvaGA9wCjyEO/YEsrIbn8DSuFId QY2Wb9IhMWES4ItmWy5dvq2wxN4rfd6Ona7fKOkoM168yui8N2Ntr0F4EpfbEzRbz6YV V4vVyj4DV/22pH/dy+2pUcSRVN5Rh+vxl5yLNi32hdmFmqEsGJjIJCajb+5h8mqvLPjq OIvQ== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:from:to:cc:subject:date:message-id:mime-version :content-transfer-encoding; bh=8kBHltz3fpi5tJOBHoxxMlZNZl2yFO4paDm36raK100=; b=B76QvmrcjxCrq+Y7hMLTS6mXG+Qzesu/thwhn/6KDyk9AEyMKEDjn5VPMQdUTfaaYT s4Kxb3cj8pfRR4UNnPFK1ocGzOK1dldgFM4x0wz5IIf0AU6t19L8idgV0HgPT+L/SpYh KRDdAuzQDGBryKvuEMJuiOB9Z1Idaw+xZ5YQpgKHqHpWY6THqBgsInkBWxSGHKOLi/x7 RtHgSWYwjMlqSTzPWWXRdSRzK06/C9xE2X26f+MsIMS+N7FpQoiBe3JIM9qzBTNpje5R lrp5HM6Aid/vQycX8mFUkFa0DK370VDr3a1fjiLFP3267v3bOvXmWrbs0fupo0ZyvJqJ nZMw== X-Gm-Message-State: AOAM533q3330x2fq+dMC0R0MfICX9/WtG4vS5f+H89SxjqR7vWTpUwTw 92ODKJRB/ffuBzJlnGL5ig== X-Google-Smtp-Source: ABdhPJzzBmHQ+Sn4JRrVsfAq41FRZTA8DxFCmeNHoYQkN1hG2JZMNdjGgz7EKW3m6mYTRjjYw1AsbA== X-Received: by 2002:a37:a154:: with SMTP id k81mr38215797qke.202.1626909360600; Wed, 21 Jul 2021 16:16:00 -0700 (PDT) Received: from bytedance.attlocal.net (ec2-52-52-7-82.us-west-1.compute.amazonaws.com. [52.52.7.82]) by smtp.gmail.com with ESMTPSA id k14sm9875038qtm.18.2021.07.21.16.15.58 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Wed, 21 Jul 2021 16:16:00 -0700 (PDT) From: Peilin Ye To: Jamal Hadi Salim , Cong Wang , Jiri Pirko , "David S. Miller" , Jakub Kicinski , netdev@vger.kernel.org Cc: linux-kernel@vger.kernel.org, Cong Wang , Peilin Ye , Peilin Ye Subject: [PATCH net-next 1/2] net/sched: act_skbmod: Add SKBMOD_F_ECN option support Date: Wed, 21 Jul 2021 16:15:47 -0700 Message-Id: X-Mailer: git-send-email 2.25.1 MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: netdev@vger.kernel.org X-Patchwork-Delegate: kuba@kernel.org From: Peilin Ye Currently, when doing rate limiting using the tc-police(8) action, the easiest way is to simply drop the packets which exceed or conform the configured bandwidth limit. Add a new option to tc-skbmod(8), so that users may use the ECN [1] extension to explicitly inform the receiver about the congestion instead of dropping packets "on the floor". The 2 least significant bits of the Traffic Class field in IPv4 and IPv6 headers are used to represent different ECN states [2]: 0b00: "Non ECN-Capable Transport", Non-ECT 0b10: "ECN Capable Transport", ECT(0) 0b01: "ECN Capable Transport", ECT(1) 0b11: "Congestion Encountered", CE As an example: $ tc filter add dev eth0 parent 1: protocol ip prio 10 \ matchall action skbmod ecn Doing the above marks all ECT(0) and ECT(1) packets as CE. It does NOT affect Non-ECT or non-IP packets. In the tc-police scenario mentioned above, users may pipe a tc-police action and a tc-skbmod "ecn" action together to achieve ECN-based rate limiting. For TCP connections, upon receiving a CE packet, the receiver will respond with an ECE packet, asking the sender to reduce their congestion window. However ECN also works with other L4 protocols e.g. DCCP and SCTP [2], and our implementation does not touch or care about L4 headers. The updated tc-skbmod SYNOPSIS looks like the following: tc ... action skbmod { set SETTABLE | swap SWAPPABLE | ecn } ... Only one of "set", "swap" or "ecn" shall be used in a single tc-skbmod command. Trying to use more than one of them at a time is considered undefined behavior; pipe multiple tc-skbmod commands together instead. "set" and "swap" only affect Ethernet packets, while "ecn" only affects IPv{4,6} packets. It is also worth mentioning that, in theory, the same effect could be achieved by piping a "police" action and a "bpf" action using the bpf_skb_ecn_set_ce() helper, but this requires eBPF programming from the user, thus impractical. Depends on patch "net/sched: act_skbmod: Skip non-Ethernet packets". [1] https://datatracker.ietf.org/doc/html/rfc3168 [2] https://en.wikipedia.org/wiki/Explicit_Congestion_Notification Reviewed-by: Cong Wang Signed-off-by: Peilin Ye --- Hi all, This patch depends on the following commit, which is in net, but not in net-next yet: https://git.kernel.org/pub/scm/linux/kernel/git/netdev/net.git/commit/?id=727d6a8b7ef3d25080fad228b2c4a1d4da5999c6 Thanks, Peilin Ye include/uapi/linux/tc_act/tc_skbmod.h | 1 + net/sched/act_skbmod.c | 44 +++++++++++++++++++-------- 2 files changed, 33 insertions(+), 12 deletions(-) diff --git a/include/uapi/linux/tc_act/tc_skbmod.h b/include/uapi/linux/tc_act/tc_skbmod.h index c525b3503797..af6ef2cfbf3d 100644 --- a/include/uapi/linux/tc_act/tc_skbmod.h +++ b/include/uapi/linux/tc_act/tc_skbmod.h @@ -17,6 +17,7 @@ #define SKBMOD_F_SMAC 0x2 #define SKBMOD_F_ETYPE 0x4 #define SKBMOD_F_SWAPMAC 0x8 +#define SKBMOD_F_ECN 0x10 struct tc_skbmod { tc_gen; diff --git a/net/sched/act_skbmod.c b/net/sched/act_skbmod.c index 8d17a543cc9f..762ceec3e6f6 100644 --- a/net/sched/act_skbmod.c +++ b/net/sched/act_skbmod.c @@ -11,6 +11,7 @@ #include #include #include +#include #include #include #include @@ -21,15 +22,13 @@ static unsigned int skbmod_net_id; static struct tc_action_ops act_skbmod_ops; -#define MAX_EDIT_LEN ETH_HLEN static int tcf_skbmod_act(struct sk_buff *skb, const struct tc_action *a, struct tcf_result *res) { struct tcf_skbmod *d = to_skbmod(a); - int action; + int action, max_edit_len, err; struct tcf_skbmod_params *p; u64 flags; - int err; tcf_lastuse_update(&d->tcf_tm); bstats_cpu_update(this_cpu_ptr(d->common.cpu_bstats), skb); @@ -38,19 +37,34 @@ static int tcf_skbmod_act(struct sk_buff *skb, const struct tc_action *a, if (unlikely(action == TC_ACT_SHOT)) goto drop; - if (!skb->dev || skb->dev->type != ARPHRD_ETHER) - return action; + max_edit_len = skb_mac_header_len(skb); + p = rcu_dereference_bh(d->skbmod_p); + flags = p->flags; + + /* tcf_skbmod_init() guarantees "flags" to be one of the following: + * 1. a combination of SKBMOD_F_{DMAC,SMAC,ETYPE} + * 2. SKBMOD_F_SWAPMAC + * 3. SKBMOD_F_ECN + * SKBMOD_F_ECN only works with IP packets; all other flags only work with Ethernet + * packets. + */ + if (flags == SKBMOD_F_ECN) { + switch (skb_protocol(skb, true)) { + case cpu_to_be16(ETH_P_IP): + case cpu_to_be16(ETH_P_IPV6): + max_edit_len += skb_network_header_len(skb); + break; + default: + goto out; + } + } else if (!skb->dev || skb->dev->type != ARPHRD_ETHER) { + goto out; + } - /* XXX: if you are going to edit more fields beyond ethernet header - * (example when you add IP header replacement or vlan swap) - * then MAX_EDIT_LEN needs to change appropriately - */ - err = skb_ensure_writable(skb, MAX_EDIT_LEN); + err = skb_ensure_writable(skb, max_edit_len); if (unlikely(err)) /* best policy is to drop on the floor */ goto drop; - p = rcu_dereference_bh(d->skbmod_p); - flags = p->flags; if (flags & SKBMOD_F_DMAC) ether_addr_copy(eth_hdr(skb)->h_dest, p->eth_dst); if (flags & SKBMOD_F_SMAC) @@ -66,6 +80,10 @@ static int tcf_skbmod_act(struct sk_buff *skb, const struct tc_action *a, ether_addr_copy(eth_hdr(skb)->h_source, (u8 *)tmpaddr); } + if (flags & SKBMOD_F_ECN) + INET_ECN_set_ce(skb); + +out: return action; drop: @@ -129,6 +147,8 @@ static int tcf_skbmod_init(struct net *net, struct nlattr *nla, index = parm->index; if (parm->flags & SKBMOD_F_SWAPMAC) lflags = SKBMOD_F_SWAPMAC; + if (parm->flags & SKBMOD_F_ECN) + lflags = SKBMOD_F_ECN; err = tcf_idr_check_alloc(tn, &index, a, bind); if (err < 0) From patchwork Wed Jul 21 23:22:44 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Peilin Ye X-Patchwork-Id: 12392495 X-Patchwork-Delegate: kuba@kernel.org 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=-15.8 required=3.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,FREEMAIL_FORGED_FROMDOMAIN,FREEMAIL_FROM, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER,INCLUDES_PATCH, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,USER_AGENT_GIT autolearn=unavailable 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 0E678C6377C for ; Wed, 21 Jul 2021 23:22:56 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id E76C46121E for ; Wed, 21 Jul 2021 23:22:55 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S231154AbhGUWmS (ORCPT ); Wed, 21 Jul 2021 18:42:18 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:38090 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S230091AbhGUWmR (ORCPT ); Wed, 21 Jul 2021 18:42:17 -0400 Received: from mail-qt1-x831.google.com (mail-qt1-x831.google.com [IPv6:2607:f8b0:4864:20::831]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 84FA9C061575; Wed, 21 Jul 2021 16:22:53 -0700 (PDT) Received: by mail-qt1-x831.google.com with SMTP id j7so3072844qtj.6; Wed, 21 Jul 2021 16:22:53 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20161025; h=from:to:cc:subject:date:message-id:in-reply-to:references :mime-version:content-transfer-encoding; bh=pozbzGVzs8EDjWr/Isfr8VZlmmrHC7hULWqF8mz9+Xo=; b=azUZRQH7bhfATqyNF86v4JQHKEKaObrAlMHQ8FX5Ck2jdYXcCdz11mIJ05zSiFFoq3 S7ZuuR5mAXoEo8j58afrfe9sge5kCcc+A5F/KRDViziVUsKPDDwt6N5MLJwhngsy2hpn 9L4Ot5h46sqVeVPk9iclYmhev4QnIV4Lq219+uPYRhpqrG5XOFEcfYu6Ep6qynefk+L/ 1wHRhrBfELR7kd2GMGVl4Ay1P6p+SrpN5ZwtQ5INx1qCX4QDLN0ZIht1kAwbSn77AR1w E7jIQiSPsbgrtZj8fO5zlLfpuNFslZJNxtlEs4IVJ1jcDBmAnmBtvs7OBadcb0Nrm6fs mkTg== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:from:to:cc:subject:date:message-id:in-reply-to :references:mime-version:content-transfer-encoding; bh=pozbzGVzs8EDjWr/Isfr8VZlmmrHC7hULWqF8mz9+Xo=; b=mC+QFgL6xm9ZnN93VhBLT3ufQuZrYKX5AyiAV+RLW4v9GkRLys/2+bntQeIFa1K1dI IkiEokhLOors6aLl8yxDDS3aTuhdagFPSNERGMWEH4nYVAObf1WyCTSe73kfC7noi9On UnpYA0HN2VfYws65AryMtgY1RvyIYXQSldZpBtDk549OQH+k+vUYGN/aIYFa3Jn9/O1q mpRI4YfMpNzYBituQeyOGTLcll3oOYs8JwvINkWc9ejI/yoR3q+EhmEaTctje2BxcxBK q4r4OvbzgGG43FHyEFQvvYEZHRGThoVgUQStl8Na9f+INIdTMezBYYqsOtqSmv25UtwR TXrg== X-Gm-Message-State: AOAM533bPZslqzqw0YN3WVjGF42I9tz8iWeaIVG8vv80+xhYwS9jiWRP BTLyUErqWd7nAHt8K6d/1A== X-Google-Smtp-Source: ABdhPJzQ8SJgmO30XBcBnvfbnsCN4ckh2jCVvOvrbZ4ELmKOrnjoJ5I8BNDeE6oJE2rPVdbt5w2Ofg== X-Received: by 2002:a05:622a:1342:: with SMTP id w2mr33443452qtk.310.1626909772739; Wed, 21 Jul 2021 16:22:52 -0700 (PDT) Received: from bytedance.attlocal.net (ec2-52-52-7-82.us-west-1.compute.amazonaws.com. [52.52.7.82]) by smtp.gmail.com with ESMTPSA id k9sm6531563qti.88.2021.07.21.16.22.51 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Wed, 21 Jul 2021 16:22:52 -0700 (PDT) From: Peilin Ye To: Shuah Khan , Jamal Hadi Salim , Cong Wang , Jiri Pirko , "David S. Miller" , Jakub Kicinski , netdev@vger.kernel.org Cc: linux-kselftest@vger.kernel.org, linux-kernel@vger.kernel.org, Cong Wang , Peilin Ye , Peilin Ye Subject: [PATCH net-next 2/2] tc-testing: Add control-plane selftest for skbmod SKBMOD_F_ECN option Date: Wed, 21 Jul 2021 16:22:44 -0700 Message-Id: <21ca3638f09c55d0e1deb439f82a1124aff80144.1626899889.git.peilin.ye@bytedance.com> X-Mailer: git-send-email 2.25.1 In-Reply-To: References: MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: netdev@vger.kernel.org X-Patchwork-Delegate: kuba@kernel.org From: Peilin Ye Recently we added a new option, SKBMOD_F_ECN, to tc-skbmod(8). Add a control-plane selftest for it. Depends on kernel patch "net/sched: act_skbmod: Add SKBMOD_F_ECN option support", as well as iproute2 patch "tc/skbmod: Introduce SKBMOD_F_ECN option". Reviewed-by: Cong Wang Signed-off-by: Peilin Ye --- Hi all, The corresponding iproute2-next patch is here: https://lore.kernel.org/netdev/20210721232053.39077-1-yepeilin.cs@gmail.com/ Thanks, Peilin Ye .../tc-testing/tc-tests/actions/skbmod.json | 24 +++++++++++++++++++ 1 file changed, 24 insertions(+) diff --git a/tools/testing/selftests/tc-testing/tc-tests/actions/skbmod.json b/tools/testing/selftests/tc-testing/tc-tests/actions/skbmod.json index 6eb4c4f97060..742f2290973e 100644 --- a/tools/testing/selftests/tc-testing/tc-tests/actions/skbmod.json +++ b/tools/testing/selftests/tc-testing/tc-tests/actions/skbmod.json @@ -417,5 +417,29 @@ "teardown": [ "$TC actions flush action skbmod" ] + }, + { + "id": "fe09", + "name": "Add skbmod action to mark ECN bits", + "category": [ + "actions", + "skbmod" + ], + "setup": [ + [ + "$TC actions flush action skbmod", + 0, + 1, + 255 + ] + ], + "cmdUnderTest": "$TC actions add action skbmod ecn", + "expExitCode": "0", + "verifyCmd": "$TC actions get action skbmod index 1", + "matchPattern": "action order [0-9]*: skbmod pipe ecn", + "matchCount": "1", + "teardown": [ + "$TC actions flush action skbmod" + ] } ]