From patchwork Fri May 12 20:23:05 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Dmitry Safonov X-Patchwork-Id: 13239672 X-Patchwork-Delegate: kuba@kernel.org Received: from lindbergh.monkeyblade.net (lindbergh.monkeyblade.net [23.128.96.19]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 891A3209AC for ; Fri, 12 May 2023 20:23:42 +0000 (UTC) Received: from mail-wm1-x332.google.com (mail-wm1-x332.google.com [IPv6:2a00:1450:4864:20::332]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 82B0B4ED6 for ; Fri, 12 May 2023 13:23:40 -0700 (PDT) Received: by mail-wm1-x332.google.com with SMTP id 5b1f17b1804b1-3f427118644so62142345e9.0 for ; Fri, 12 May 2023 13:23:40 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=arista.com; s=google; t=1683923020; x=1686515020; h=content-transfer-encoding:mime-version:references:in-reply-to :message-id:date:subject:cc:to:from:from:to:cc:subject:date :message-id:reply-to; bh=Z4qr5vCw/0NOEaSHOwxwN07T1+ESdNZE5gRM4K/uHIo=; b=Ok/UFNe9C/qGFROhNKzTfjNyJh4MGaqF2E19rZI7wo4PUsg29CHuKs7mvaq0szwZ+c Pq7c3WgAX7fBjJBEygNZvJU2Z+B/NgPlM0CVv5+sONuH5EyubKcfnK1R41P3PipM9ApE bCAu164xtg8Lej8L/MoyNtDhbzu9sipdKqqI62nwk0Zgfm54ts63R8uhVo4tkH2QJ9Zb lUNYstBb4ZuZqHn+O28C0DisqdYrFv9d8/VCe7JTKZzw0ZaqV3ZzbS8vQvVJFx6xxfy0 StqStX3/wlAoumyKkbdyoMBpVKHx+KHqhsZnrfaeJduiarK08zQVpBLfMHt3Kjsruxhe 7F/g== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20221208; t=1683923020; x=1686515020; h=content-transfer-encoding:mime-version:references:in-reply-to :message-id:date:subject:cc:to:from:x-gm-message-state:from:to:cc :subject:date:message-id:reply-to; bh=Z4qr5vCw/0NOEaSHOwxwN07T1+ESdNZE5gRM4K/uHIo=; b=Bg/2M0+EBcEx7q9gwVzXFP4loDFKTVQR6osIuFcxkinCuFarKl2+k12QRt4MGvPzr6 WZ79mNVNd2wNz5QrsEhAyyl3jMV27rbtf79i+OC5I8sQhFXyoeJKEnwYa7p77PKfEDxu /mEWU5OWWkshuGiFVjz3fvSIRhTUY49LA0r+tAn8V3pbTHW9dv42xqPxQINU8WSe30d+ TJ/dkATxICFFy6jXZ04Pn73pHZDOpblC+WlO3KcIaZ24XUPVF28MhtdumXeEjHMOkxWi cxZ75/Y42epF1lYAHH0ZqL9eBJt/dV9rikeedg8IO7rSrazEWOBrAx9Sl4AC/k99D3Sy We+g== X-Gm-Message-State: AC+VfDy7cnuI64lOiNofrIvvscggkuhMkyVnELks4JnqS6o1NjnTNwYZ AKfdUuG//GaW3W9z5mFLm9luLg== X-Google-Smtp-Source: ACHHUZ74q8BxnO1TXR22tQxK7owikieCDorl7mzGFLwSnK11dpHI7P2ZY/Ne4jrwZJkjMdWQ+fCN1A== X-Received: by 2002:a1c:6a18:0:b0:3f4:294d:8529 with SMTP id f24-20020a1c6a18000000b003f4294d8529mr12499190wmc.19.1683923020032; Fri, 12 May 2023 13:23:40 -0700 (PDT) Received: from Mindolluin.ire.aristanetworks.com ([217.173.96.166]) by smtp.gmail.com with ESMTPSA id n9-20020a05600c294900b003f423508c6bsm17304527wmd.44.2023.05.12.13.23.38 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Fri, 12 May 2023 13:23:39 -0700 (PDT) From: Dmitry Safonov To: linux-kernel@vger.kernel.org, David Ahern , Eric Dumazet , Paolo Abeni , Jakub Kicinski , "David S. Miller" Cc: Dmitry Safonov , Andy Lutomirski , Ard Biesheuvel , Bob Gilligan , Dan Carpenter , David Laight , Dmitry Safonov <0x7f454c46@gmail.com>, Eric Biggers , "Eric W. Biederman" , Francesco Ruggeri , Herbert Xu , Hideaki YOSHIFUJI , Ivan Delalande , Leonard Crestez , Salam Noureddine , netdev@vger.kernel.org Subject: [PATCH v6 15/21] net/tcp: Add tcp_hash_fail() ratelimited logs Date: Fri, 12 May 2023 21:23:05 +0100 Message-Id: <20230512202311.2845526-16-dima@arista.com> X-Mailer: git-send-email 2.40.0 In-Reply-To: <20230512202311.2845526-1-dima@arista.com> References: <20230512202311.2845526-1-dima@arista.com> Precedence: bulk X-Mailing-List: netdev@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 X-Spam-Status: No, score=-2.1 required=5.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,DKIM_VALID_EF,RCVD_IN_DNSWL_NONE, SPF_HELO_NONE,SPF_NONE,T_SCC_BODY_TEXT_LINE,URIBL_BLOCKED autolearn=ham autolearn_force=no version=3.4.6 X-Spam-Checker-Version: SpamAssassin 3.4.6 (2021-04-09) on lindbergh.monkeyblade.net X-Patchwork-Delegate: kuba@kernel.org Add a helper for logging connection-detailed messages for failed TCP hash verification (both MD5 and AO). Co-developed-by: Francesco Ruggeri Signed-off-by: Francesco Ruggeri Co-developed-by: Salam Noureddine Signed-off-by: Salam Noureddine Signed-off-by: Dmitry Safonov --- include/net/tcp.h | 17 ++++++++++++++--- include/net/tcp_ao.h | 29 +++++++++++++++++++++++++++++ net/ipv4/tcp.c | 23 +++++++++++++---------- net/ipv4/tcp_ao.c | 7 +++++++ 4 files changed, 63 insertions(+), 13 deletions(-) diff --git a/include/net/tcp.h b/include/net/tcp.h index 57c7658cf296..e7b077805d9e 100644 --- a/include/net/tcp.h +++ b/include/net/tcp.h @@ -2605,12 +2605,19 @@ tcp_inbound_hash(struct sock *sk, const struct request_sock *req, int l3index; /* Invalid option or two times meet any of auth options */ - if (tcp_parse_auth_options(th, &md5_location, &aoh)) + if (tcp_parse_auth_options(th, &md5_location, &aoh)) { + tcp_hash_fail("TCP segment has incorrect auth options set", + family, skb, ""); return SKB_DROP_REASON_TCP_AUTH_HDR; + } if (req) { - if (tcp_rsk_used_ao(req) != !!aoh) + if (tcp_rsk_used_ao(req) != !!aoh) { + tcp_hash_fail("TCP connection can't start/end using TCP-AO", + family, skb, "%s", + !aoh ? "missing AO" : "AO signed"); return SKB_DROP_REASON_TCP_AOFAILURE; + } } /* sdif set, means packet ingressed via a device @@ -2625,10 +2632,14 @@ tcp_inbound_hash(struct sock *sk, const struct request_sock *req, * the last key is impossible to remove, so there's * always at least one current_key. */ - if (tcp_ao_required(sk, saddr, family, true)) + if (tcp_ao_required(sk, saddr, family, true)) { + tcp_hash_fail("AO hash is required, but not found", + family, skb, "L3 index %d", l3index); return SKB_DROP_REASON_TCP_AONOTFOUND; + } if (unlikely(tcp_md5_do_lookup(sk, l3index, saddr, family))) { NET_INC_STATS(sock_net(sk), LINUX_MIB_TCPMD5NOTFOUND); + tcp_hash_fail("MD5 Hash not found", family, skb, ""); return SKB_DROP_REASON_TCP_MD5NOTFOUND; } return SKB_NOT_DROPPED_YET; diff --git a/include/net/tcp_ao.h b/include/net/tcp_ao.h index bd67e3680a2b..391b8260c325 100644 --- a/include/net/tcp_ao.h +++ b/include/net/tcp_ao.h @@ -105,6 +105,35 @@ struct tcp_ao_info { struct rcu_head rcu; }; +#define tcp_hash_fail(msg, family, skb, fmt, ...) \ +do { \ + const struct tcphdr *th = tcp_hdr(skb); \ + char hdr_flags[5] = {}; \ + char *f = hdr_flags; \ + \ + if (th->fin) \ + *f++ = 'F'; \ + if (th->syn) \ + *f++ = 'S'; \ + if (th->rst) \ + *f++ = 'R'; \ + if (th->ack) \ + *f++ = 'A'; \ + if (f != hdr_flags) \ + *f = ' '; \ + if (family == AF_INET) { \ + net_info_ratelimited("%s for (%pI4, %d)->(%pI4, %d) %s" fmt "\n", \ + msg, &ip_hdr(skb)->saddr, ntohs(th->source), \ + &ip_hdr(skb)->daddr, ntohs(th->dest), \ + hdr_flags, ##__VA_ARGS__); \ + } else { \ + net_info_ratelimited("%s for [%pI6c]:%u->[%pI6c]:%u %s" fmt "\n", \ + msg, &ipv6_hdr(skb)->saddr, ntohs(th->source), \ + &ipv6_hdr(skb)->daddr, ntohs(th->dest), \ + hdr_flags, ##__VA_ARGS__); \ + } \ +} while (0) + #ifdef CONFIG_TCP_AO /* TCP-AO structures and functions */ diff --git a/net/ipv4/tcp.c b/net/ipv4/tcp.c index e8c62fbc7ab7..77956937ada8 100644 --- a/net/ipv4/tcp.c +++ b/net/ipv4/tcp.c @@ -4487,7 +4487,6 @@ tcp_inbound_md5_hash(const struct sock *sk, const struct sk_buff *skb, * o MD5 hash and we're not expecting one. * o MD5 hash and its wrong. */ - const struct tcphdr *th = tcp_hdr(skb); const struct tcp_sock *tp = tcp_sk(sk); struct tcp_md5sig_key *key; int genhash; @@ -4497,6 +4496,7 @@ tcp_inbound_md5_hash(const struct sock *sk, const struct sk_buff *skb, if (!key && hash_location) { NET_INC_STATS(sock_net(sk), LINUX_MIB_TCPMD5UNEXPECTED); + tcp_hash_fail("Unexpected MD5 Hash found", family, skb, ""); return SKB_DROP_REASON_TCP_MD5UNEXPECTED; } @@ -4512,16 +4512,19 @@ tcp_inbound_md5_hash(const struct sock *sk, const struct sk_buff *skb, if (genhash || memcmp(hash_location, newhash, 16) != 0) { NET_INC_STATS(sock_net(sk), LINUX_MIB_TCPMD5FAILURE); if (family == AF_INET) { - net_info_ratelimited("MD5 Hash failed for (%pI4, %d)->(%pI4, %d)%s L3 index %d\n", - saddr, ntohs(th->source), - daddr, ntohs(th->dest), - genhash ? " tcp_v4_calc_md5_hash failed" - : "", l3index); + tcp_hash_fail("MD5 Hash failed", AF_INET, skb, "%s L3 index %d", + genhash ? "tcp_v4_calc_md5_hash failed" + : "", l3index); } else { - net_info_ratelimited("MD5 Hash %s for [%pI6c]:%u->[%pI6c]:%u L3 index %d\n", - genhash ? "failed" : "mismatch", - saddr, ntohs(th->source), - daddr, ntohs(th->dest), l3index); + if (genhash) { + tcp_hash_fail("MD5 Hash failed", + AF_INET6, skb, "L3 index %d", + l3index); + } else { + tcp_hash_fail("MD5 Hash mismatch", + AF_INET6, skb, "L3 index %d", + l3index); + } } return SKB_DROP_REASON_TCP_MD5FAILURE; } diff --git a/net/ipv4/tcp_ao.c b/net/ipv4/tcp_ao.c index 4ef0418b9f5a..2f030cd5e605 100644 --- a/net/ipv4/tcp_ao.c +++ b/net/ipv4/tcp_ao.c @@ -671,6 +671,8 @@ tcp_ao_verify_hash(const struct sock *sk, const struct sk_buff *skb, NET_INC_STATS(sock_net(sk), LINUX_MIB_TCPAOBAD); atomic64_inc(&info->counters.pkt_bad); atomic64_inc(&key->pkt_bad); + tcp_hash_fail("AO hash wrong length", family, skb, + "%u != %d", maclen, tcp_ao_maclen(key)); return SKB_DROP_REASON_TCP_AOFAILURE; } @@ -681,6 +683,7 @@ tcp_ao_verify_hash(const struct sock *sk, const struct sk_buff *skb, NET_INC_STATS(sock_net(sk), LINUX_MIB_TCPAOBAD); atomic64_inc(&info->counters.pkt_bad); atomic64_inc(&key->pkt_bad); + tcp_hash_fail("AO hash mismatch", family, skb, ""); return SKB_DROP_REASON_TCP_AOFAILURE; } NET_INC_STATS(sock_net(sk), LINUX_MIB_TCPAOGOOD); @@ -706,6 +709,8 @@ tcp_inbound_ao_hash(struct sock *sk, const struct sk_buff *skb, info = rcu_dereference(tcp_sk(sk)->ao_info); if (!info) { NET_INC_STATS(sock_net(sk), LINUX_MIB_TCPAOKEYNOTFOUND); + tcp_hash_fail("AO key not found", family, skb, + "keyid: %u", aoh->keyid); return SKB_DROP_REASON_TCP_AOUNEXPECTED; } @@ -804,6 +809,8 @@ tcp_inbound_ao_hash(struct sock *sk, const struct sk_buff *skb, key_not_found: NET_INC_STATS(sock_net(sk), LINUX_MIB_TCPAOKEYNOTFOUND); atomic64_inc(&info->counters.key_not_found); + tcp_hash_fail("Requested by the peer AO key id not found", + family, skb, ""); return SKB_DROP_REASON_TCP_AOKEYNOTFOUND; } EXPORT_SYMBOL_GPL(tcp_inbound_ao_hash);