From patchwork Mon Oct 23 19:22:07 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Dmitry Safonov X-Patchwork-Id: 13433451 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 D1E40224E4 for ; Mon, 23 Oct 2023 19:23:24 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=arista.com header.i=@arista.com header.b="M7ptxhDu" Received: from mail-wm1-x335.google.com (mail-wm1-x335.google.com [IPv6:2a00:1450:4864:20::335]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 93A6F171B for ; Mon, 23 Oct 2023 12:22:59 -0700 (PDT) Received: by mail-wm1-x335.google.com with SMTP id 5b1f17b1804b1-40837ebba42so27045745e9.0 for ; Mon, 23 Oct 2023 12:22:58 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=arista.com; s=google; t=1698088975; x=1698693775; 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=YaLyEMYJtggtWrtStOtLZq/UC24SdFNNRozlG1IgPAc=; b=M7ptxhDuFAQtR21kVMWx2BCV28n880Vx1PMU4eTB2y4dnAAB4SxyzwWLagRRcV9w27 IwQZb3gUdDvC3uhrqCQaF2Z1lpbcnh6F6r0khg42lsaqVjFA8K3p3fDYQ7EHZfrbSRav xo0cPBfae+Yh6HcZe9pdnCZvuiQv7vKreGlBFGptyvGdZMktYPMfOj7C5UCpmVuw+tuP 8xP3+VRJwHdKJ66g1BjzfRkSUHktmzgTCW+2GIjJZJIQrFc2UakIZH0I5c9CBTZfaMqe yugUeoH0nipfuQCreK2pemtlux6RPiM6S9TO19pQJLpEWpvAxksrOoNH1OTVYjYbUOHe PH9g== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20230601; t=1698088975; x=1698693775; 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=YaLyEMYJtggtWrtStOtLZq/UC24SdFNNRozlG1IgPAc=; b=Oowe05CKBCtHYaYOpOD1Ywg3n1NHJFwrFntfol0WauHF1r+SS4pBWOyL+bKhVFpU+H gLlvd+OYOqrbBjlNc0ouIsn1hYtzlV3m/jAzb8/Q+DWd4bs3D88NKjig0Q+o7SoqYKR8 8qaYJFiOSBat9tcqhyf9yMvzMtC2ostGgjrDbm/koPy45MSLX4/2GZWsSOQOq6Bw1sGN K4rQI/fQTPp5N3tTzwXld3a+b1IqE/ceF7i7+Yo9osxa8nD6kqLVHdUQEOpjwA+H9q8Q sKPRlPv3Zr9axDrgYXvIEVSUM+gsv2D1PkFzYIWY7J8H8aYDLzW0pkqMnUHHaUHnNeN9 EXjw== X-Gm-Message-State: AOJu0YxD2OPwstCREak8lyBAr7sBULY+XaU9p/41VnvUvU+Ni7YdL9nr K1fm0hWa4m+Bd7wf8En84lCCSw== X-Google-Smtp-Source: AGHT+IELlnjCYF6NMUj8EjfYOp+hRkexMiQbWVYqV7zP2YWb65C2GXgelQ3uny8ana0BNqb25ujH8Q== X-Received: by 2002:a05:600c:468e:b0:408:500b:a476 with SMTP id p14-20020a05600c468e00b00408500ba476mr8051615wmo.20.1698088975181; Mon, 23 Oct 2023 12:22:55 -0700 (PDT) Received: from Mindolluin.ire.aristanetworks.com ([217.173.96.166]) by smtp.gmail.com with ESMTPSA id ay20-20020a05600c1e1400b00407460234f9sm10142088wmb.21.2023.10.23.12.22.53 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Mon, 23 Oct 2023 12:22:54 -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 v16 net-next 15/23] net/tcp: Add tcp_hash_fail() ratelimited logs Date: Mon, 23 Oct 2023 20:22:07 +0100 Message-ID: <20231023192217.426455-16-dima@arista.com> X-Mailer: git-send-email 2.42.0 In-Reply-To: <20231023192217.426455-1-dima@arista.com> References: <20231023192217.426455-1-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 d29c8a867f0e..c93ac6cc12c4 100644 --- a/include/net/tcp.h +++ b/include/net/tcp.h @@ -2746,12 +2746,18 @@ 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; } } @@ -2768,10 +2774,14 @@ 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 846ddc023ac1..8594a4bf764e 100644 --- a/net/ipv4/tcp.c +++ b/net/ipv4/tcp.c @@ -4381,7 +4381,6 @@ 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]; @@ -4391,6 +4390,7 @@ 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; } @@ -4406,16 +4406,19 @@ 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; }