From patchwork Fri Feb 4 13:58:14 2022 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Guillaume Nault X-Patchwork-Id: 539966 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 27164C433F5 for ; Fri, 4 Feb 2022 13:58:23 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1359114AbiBDN6U (ORCPT ); Fri, 4 Feb 2022 08:58:20 -0500 Received: from us-smtp-delivery-124.mimecast.com ([170.10.129.124]:58674 "EHLO us-smtp-delivery-124.mimecast.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1359154AbiBDN6T (ORCPT ); Fri, 4 Feb 2022 08:58:19 -0500 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1643983099; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version:content-type:content-type: in-reply-to:in-reply-to:references:references; bh=MBMyk3IZsR5ozoJLuOW+sHZ0Vu+57g26uCSnHB4yqHg=; b=RmWj8lULiS3JwegvZMNYJFj1sxEqzvUVCAkJtbD6aHTO6qHIbswmy7pyIAoK5G1r9aZpa+ U105yEcMDs5Gf0vdYO8TDU+Y88tN6z1mM6X3fL7nVXNYffeP8qcrkGw9q03QR7YGi9k+nd jQMzmeKds21n2DJSXC1ee7aNJ7ASpoA= Received: from mail-wr1-f72.google.com (mail-wr1-f72.google.com [209.85.221.72]) by relay.mimecast.com with ESMTP with STARTTLS (version=TLSv1.2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id us-mta-173-NR5Q1XJAPs2Dta6bcj72lA-1; Fri, 04 Feb 2022 08:58:18 -0500 X-MC-Unique: NR5Q1XJAPs2Dta6bcj72lA-1 Received: by mail-wr1-f72.google.com with SMTP id c10-20020adfa30a000000b001d79c73b64bso2065692wrb.1 for ; Fri, 04 Feb 2022 05:58:17 -0800 (PST) X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20210112; h=x-gm-message-state:date:from:to:cc:subject:message-id:references :mime-version:content-disposition:in-reply-to; bh=MBMyk3IZsR5ozoJLuOW+sHZ0Vu+57g26uCSnHB4yqHg=; b=b+hi8gOirhvsL5C4Ezx84k2fpSwopDTi3vjo2vDLG4AdgS8VTko7WUVwZ/sao9loht oyL5QIPDLlCofd3gFoJwRP+e5w4jFyu40rlMuLoQn8Z61IjGTmglEvt1LgVolQ0zeD5O gOOpWVpp78Z/oVY9rR54lHko2gss0WL2iFxioOFbkOL9yRQxeuoLjnbdZc5oujPyZr9v vuiRb8aUTdOQLaduPq0Ey1k+ws75gI/xXUhgziJhwk/YjpGb6lwh1yTtURudL6HaY4kr rP1ha1N6bPDqj0kYl111sIz53W/otTyOxvpAOMPnJmK/oGQKOz4sGyZBHD8z1nqRIz9/ HaBQ== X-Gm-Message-State: AOAM533XI2cgwFyF+mjpY5DcZxrrMNm8w/2yVd/Bd/DAHyXvkqd9GHYQ L8nbm6n1pzAYPQPXNNO7RvdS44ZayJXN4eXqy43sr2qKyVY/safq1iVUY8Mf+UYog8ehqaCQ0eL NFBP5WdSWZ6uOvW4IhZkDzqZlCkr2 X-Received: by 2002:a05:6000:25c:: with SMTP id m28mr2505934wrz.511.1643983096746; Fri, 04 Feb 2022 05:58:16 -0800 (PST) X-Google-Smtp-Source: ABdhPJxwFnp0E5TKW9qae8qOTeJ2DC4Arzk0wVFQek4amDQpq4oIdfQziIY2s9OwcMQeIpq8RT1BUQ== X-Received: by 2002:a05:6000:25c:: with SMTP id m28mr2505922wrz.511.1643983096587; Fri, 04 Feb 2022 05:58:16 -0800 (PST) Received: from pc-4.home (2a01cb058918ce00dd1a5a4f9908f2d5.ipv6.abo.wanadoo.fr. [2a01:cb05:8918:ce00:dd1a:5a4f:9908:f2d5]) by smtp.gmail.com with ESMTPSA id bg26sm10366044wmb.48.2022.02.04.05.58.15 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Fri, 04 Feb 2022 05:58:16 -0800 (PST) Date: Fri, 4 Feb 2022 14:58:14 +0100 From: Guillaume Nault To: David Miller , Jakub Kicinski Cc: netdev@vger.kernel.org, Hideaki YOSHIFUJI , David Ahern , Toke =?iso-8859-1?q?H=F8iland-J=F8rgensen?= , Shuah Khan , linux-kselftest@vger.kernel.org, Russell Strong , Dave Taht Subject: [PATCH net-next 2/4] ipv4: Stop taking ECN bits into account in fib4-rules Message-ID: <706ed5f33756ea0989373f1e312e248095d458d5.1643981839.git.gnault@redhat.com> References: MIME-Version: 1.0 Content-Disposition: inline In-Reply-To: Precedence: bulk List-ID: X-Mailing-List: linux-kselftest@vger.kernel.org Use the new dscp_t type to replace the tos field of struct fib4_rule, so that fib4-rules consistently ignore ECN bits. Before this patch, fib4-rules did accept rules with the high order ECN bit set (but not the low order one). Also, it relied on its callers masking the ECN bits of ->flowi4_tos to prevent those from influencing the result. This was brittle and a few call paths still do the lookup without masking the ECN bits first. After this patch fib4-rules only compare the DSCP bits. ECN can't influence the result anymore, even if the caller didn't mask these bits. Also, fib4-rules now must have both ECN bits cleared or they will be rejected. Signed-off-by: Guillaume Nault --- net/ipv4/fib_rules.c | 18 ++++++----- tools/testing/selftests/net/fib_rule_tests.sh | 30 ++++++++++++++++++- 2 files changed, 39 insertions(+), 9 deletions(-) diff --git a/net/ipv4/fib_rules.c b/net/ipv4/fib_rules.c index e0b6c8b6de57..117c48571cf0 100644 --- a/net/ipv4/fib_rules.c +++ b/net/ipv4/fib_rules.c @@ -23,6 +23,7 @@ #include #include #include +#include #include #include #include @@ -35,7 +36,7 @@ struct fib4_rule { struct fib_rule common; u8 dst_len; u8 src_len; - u8 tos; + dscp_t dscp; __be32 src; __be32 srcmask; __be32 dst; @@ -49,7 +50,7 @@ static bool fib4_rule_matchall(const struct fib_rule *rule) { struct fib4_rule *r = container_of(rule, struct fib4_rule, common); - if (r->dst_len || r->src_len || r->tos) + if (r->dst_len || r->src_len || r->dscp) return false; return fib_rule_matchall(rule); } @@ -185,7 +186,7 @@ INDIRECT_CALLABLE_SCOPE int fib4_rule_match(struct fib_rule *rule, ((daddr ^ r->dst) & r->dstmask)) return 0; - if (r->tos && (r->tos != fl4->flowi4_tos)) + if (r->dscp && r->dscp != inet_dsfield_to_dscp(fl4->flowi4_tos)) return 0; if (rule->ip_proto && (rule->ip_proto != fl4->flowi4_proto)) @@ -225,10 +226,12 @@ static int fib4_rule_configure(struct fib_rule *rule, struct sk_buff *skb, int err = -EINVAL; struct fib4_rule *rule4 = (struct fib4_rule *) rule; - if (frh->tos & ~IPTOS_TOS_MASK) { - NL_SET_ERR_MSG(extack, "Invalid tos"); + if (!inet_validate_dscp(frh->tos)) { + NL_SET_ERR_MSG(extack, + "Invalid dsfield (tos): ECN bits must be 0"); goto errout; } + rule4->dscp = inet_dsfield_to_dscp(frh->tos); /* split local/main if they are not already split */ err = fib_unmerge(net); @@ -270,7 +273,6 @@ static int fib4_rule_configure(struct fib_rule *rule, struct sk_buff *skb, rule4->srcmask = inet_make_mask(rule4->src_len); rule4->dst_len = frh->dst_len; rule4->dstmask = inet_make_mask(rule4->dst_len); - rule4->tos = frh->tos; net->ipv4.fib_has_custom_rules = true; @@ -313,7 +315,7 @@ static int fib4_rule_compare(struct fib_rule *rule, struct fib_rule_hdr *frh, if (frh->dst_len && (rule4->dst_len != frh->dst_len)) return 0; - if (frh->tos && (rule4->tos != frh->tos)) + if (frh->tos && inet_dscp_to_dsfield(rule4->dscp) != frh->tos) return 0; #ifdef CONFIG_IP_ROUTE_CLASSID @@ -337,7 +339,7 @@ static int fib4_rule_fill(struct fib_rule *rule, struct sk_buff *skb, frh->dst_len = rule4->dst_len; frh->src_len = rule4->src_len; - frh->tos = rule4->tos; + frh->tos = inet_dscp_to_dsfield(rule4->dscp); if ((rule4->dst_len && nla_put_in_addr(skb, FRA_DST, rule4->dst)) || diff --git a/tools/testing/selftests/net/fib_rule_tests.sh b/tools/testing/selftests/net/fib_rule_tests.sh index d7a9ab3be1d3..4f70baad867d 100755 --- a/tools/testing/selftests/net/fib_rule_tests.sh +++ b/tools/testing/selftests/net/fib_rule_tests.sh @@ -215,10 +215,25 @@ fib_rule4_test_match_n_redirect() log_test $? 0 "rule4 del by pref: $description" } +fib_rule4_test_reject() +{ + local match="$1" + local rc + + $IP rule add $match table $RTABLE 2>/dev/null + rc=$? + log_test $rc 2 "rule4 check: $match" + + if [ $rc -eq 0 ]; then + $IP rule del $match table $RTABLE + fi +} + fib_rule4_test() { local getmatch local match + local cnt # setup the fib rule redirect route $IP route add table $RTABLE default via $GW_IP4 dev $DEV onlink @@ -234,8 +249,21 @@ fib_rule4_test() fib_rule4_test_match_n_redirect "$match" "$match" "iif redirect to table" ip netns exec testns sysctl -qw net.ipv4.ip_forward=0 + # Reject dsfield (tos) options which have ECN bits set + for cnt in $(seq 1 3); do + match="dsfield $cnt" + fib_rule4_test_reject "$match" + done + + # Don't take ECN bits into account when matching on dsfield match="tos 0x10" - fib_rule4_test_match_n_redirect "$match" "$match" "tos redirect to table" + for cnt in "0x10" "0x11" "0x12" "0x13"; do + # Using option 'tos' instead of 'dsfield' as old iproute2 + # versions don't support 'dsfield' in ip rule show. + getmatch="tos $cnt" + fib_rule4_test_match_n_redirect "$match" "$getmatch" \ + "$getmatch redirect to table" + done match="fwmark 0x64" getmatch="mark 0x64"