From patchwork Wed Oct 18 20:57:29 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Dmitry Safonov X-Patchwork-Id: 13427900 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 9313C4290D for ; Wed, 18 Oct 2023 20:58:58 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=arista.com header.i=@arista.com header.b="crEcC9QI" Received: from mail-wm1-x329.google.com (mail-wm1-x329.google.com [IPv6:2a00:1450:4864:20::329]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 1D623D5D for ; Wed, 18 Oct 2023 13:58:47 -0700 (PDT) Received: by mail-wm1-x329.google.com with SMTP id 5b1f17b1804b1-4064876e8b8so73523435e9.0 for ; Wed, 18 Oct 2023 13:58:46 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=arista.com; s=google; t=1697662725; x=1698267525; darn=vger.kernel.org; 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=tAQr0IaTlfLoyeWMGo6Za+WZwn+RFLOxENAPFnFYpTQ=; b=crEcC9QIrmZUdatPeyqpEZGzDEKv2JwSdKcbBlVHH+zLDtx+xkYzAZAPcVKCOny+w4 26mHn8VSAu/iHGjoj/QDM0E7s1kLRcqdOjbIGLvQ/2zN0oJ9hLSXckYcT168Kiz16WoH Uz0Ocfsq1KnHVatfTFr82tI/exBSMwVOG3dEiYnx5DETWjPSwYo09W6axfUV1T4qCDSS 37U91Q35PcphQ/ZIePbPqm3BkFMjsrqDsJWLcq5lGerAj9u/8ggl+a3yJ4QTPxdub4W1 CcQzpUVGdFvHDwA0Vq2rbVuHFkUGkAVKCGAvkzV/SA3u7lS83/NOeXY5hWhnL/TSlXwe Ii0Q== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20230601; t=1697662725; x=1698267525; 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=tAQr0IaTlfLoyeWMGo6Za+WZwn+RFLOxENAPFnFYpTQ=; b=vZl2Jp036foM97mVPGb9m54RwzNDh1dZWeYrC4b4zaqDAN64ELZrnI1fMRlktWS/Nj CWeRwxIrj8sYzWvxfiO848ZYcX+GpQBxucMF4Nuys6XT463sVryh6joqYuuuKzpaheDp 7rEjMsQ4gL9XEFWvDn322MlAJ+Alyk/u1elWhufo/aCyxa9V8UnTcI4RqyX4kNFpYRVx Rkmhzyyt7xyp0mZIyGp8PInMD9eYoN5MoyFYYMa8OtM4JV4OcjKYLAMe/r55kWpBxc/I o9IOp214AcPMdiq1/0/VR2Uz94EWpFmohNUMnU5Bbd3yLmJYLg25STXTgdq6syNB260e EQUg== X-Gm-Message-State: AOJu0YxqfIiiHmkkqbkuKVQbXmxHqbbSLTj1wUG7heQgWtNXu7DZEySY 5eVTZPPTzEZlG+7aW1OTJbYjYQ== X-Google-Smtp-Source: AGHT+IGcdA7r1Qm03GzZdMcGoaAPc5e5r8vTQs8sb8nJw4rT3MMcaOEe2EXP9NmOwuJuMmIOd2oRMA== X-Received: by 2002:a05:600c:4fc1:b0:3fe:2b8c:9f0b with SMTP id o1-20020a05600c4fc100b003fe2b8c9f0bmr338691wmq.23.1697662724930; Wed, 18 Oct 2023 13:58:44 -0700 (PDT) Received: from Mindolluin.ire.aristanetworks.com ([217.173.96.166]) by smtp.gmail.com with ESMTPSA id x19-20020a05600c421300b003fc16ee2864sm2569006wmh.48.2023.10.18.13.58.43 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Wed, 18 Oct 2023 13:58:44 -0700 (PDT) From: Dmitry Safonov To: David Ahern , Eric Dumazet , Paolo Abeni , Jakub Kicinski , "David S. Miller" Cc: linux-kernel@vger.kernel.org, Dmitry Safonov , Andy Lutomirski , Ard Biesheuvel , Bob Gilligan , Dan Carpenter , David Laight , Dmitry Safonov <0x7f454c46@gmail.com>, Donald Cassidy , Eric Biggers , "Eric W. Biederman" , Francesco Ruggeri , "Gaillardetz, Dominik" , Herbert Xu , Hideaki YOSHIFUJI , Ivan Delalande , Leonard Crestez , "Nassiri, Mohammad" , Salam Noureddine , Simon Horman , "Tetreault, Francois" , netdev@vger.kernel.org Subject: [PATCH v15 net-next 15/23] net/tcp: Add tcp_hash_fail() ratelimited logs Date: Wed, 18 Oct 2023 21:57:29 +0100 Message-ID: <20231018205806.322831-16-dima@arista.com> X-Mailer: git-send-email 2.42.0 In-Reply-To: <20231018205806.322831-1-dima@arista.com> References: <20231018205806.322831-1-dima@arista.com> Precedence: bulk X-Mailing-List: netdev@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 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 Acked-by: David Ahern --- include/net/tcp.h | 14 ++++++++++++-- include/net/tcp_ao.h | 29 +++++++++++++++++++++++++++++ net/ipv4/tcp.c | 23 +++++++++++++---------- net/ipv4/tcp_ao.c | 7 +++++++ 4 files changed, 61 insertions(+), 12 deletions(-) diff --git a/include/net/tcp.h b/include/net/tcp.h index c65408483c21..ffbcc28a89b4 100644 --- a/include/net/tcp.h +++ b/include/net/tcp.h @@ -2716,12 +2716,18 @@ 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) { NET_INC_STATS(sock_net(sk), LINUX_MIB_TCPAOBAD); + 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; } } @@ -2738,10 +2744,14 @@ 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 0c3516d1b968..4da6e3657913 100644 --- a/include/net/tcp_ao.h +++ b/include/net/tcp_ao.h @@ -118,6 +118,35 @@ 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 7ae093751e47..0d47c4891de5 100644 --- a/net/ipv4/tcp.c +++ b/net/ipv4/tcp.c @@ -4371,7 +4371,6 @@ 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; u8 newhash[16]; @@ -4381,6 +4380,7 @@ 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; } @@ -4396,16 +4396,19 @@ 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 7e14bcd4dfd4..f76fcb93499d 100644 --- a/net/ipv4/tcp_ao.c +++ b/net/ipv4/tcp_ao.c @@ -800,6 +800,8 @@ 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; } @@ -814,6 +816,7 @@ 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, ""); kfree(hash_buf); return SKB_DROP_REASON_TCP_AOFAILURE; } @@ -841,6 +844,8 @@ 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; } @@ -942,6 +947,8 @@ 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; }