From patchwork Thu Oct 27 20:43:31 2022 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Dmitry Safonov X-Patchwork-Id: 619308 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 C430BFA3745 for ; Thu, 27 Oct 2022 20:49:52 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S237059AbiJ0Utu (ORCPT ); Thu, 27 Oct 2022 16:49:50 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:42340 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S237029AbiJ0UsN (ORCPT ); Thu, 27 Oct 2022 16:48:13 -0400 Received: from mail-wr1-x42b.google.com (mail-wr1-x42b.google.com [IPv6:2a00:1450:4864:20::42b]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id F1BAB5590 for ; Thu, 27 Oct 2022 13:44:36 -0700 (PDT) Received: by mail-wr1-x42b.google.com with SMTP id w14so4155631wru.8 for ; Thu, 27 Oct 2022 13:44:36 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=arista.com; s=google; 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=zKqpBppUUTfj8qPMla2g/eqAPUAs1l844TLIW4L/wKM=; b=aZ4J6HLyTTtGQQ3ADZYb5vbN8t8obXuP8POZjn8duiWtHgn9fBwnmHEQSRrwL94vk1 c+rGmQZI1E69hkTQaJW/EDCo9lF3LmKXtzk8xE/XzrgrLWgMnv2q2dqtjgJZ0ZHwp92t uF+lXT3lbGRsZ3F32JPkmlYcDqQqwPKD/FGvoYSPRcG41IWF2ZafRJll1rrI3EJ2OCwL IL6tSdLYnnuok3K6cRzjgu2gaElPqBamWPU+auDQ2nT40gGMqqDnZJskjajmS76+anCq Oes34gjuUr5I4xRMPjMffXDWAY+59+dgVZRqzgZg2PUVenbTwEfrZDmB+jNweyXvt86w S1VQ== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20210112; 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=zKqpBppUUTfj8qPMla2g/eqAPUAs1l844TLIW4L/wKM=; b=BYxa2Oy18vUrkfrjA+O93Lg0RtyEt0Cs4TpXDSyligfKQPuY4/0UmFdU7Nb3typw+C dgJc0gp3GP3xc6+KO6PxPBBOND9KBzbiZTRQrIdEMP/Mbt/BmM5blF2bAPQaZ7PmTwW9 Qw54QqWxffCL6e8CLzAhU8IiyzyhtFVpub/sOiWDYpkSf5/bExulx1PKeB2bx4Gw8LRc oBrWLN1vJmMxGlQ69o5NPZXIQ9xxYbN5e/RIO52GYRIJf27K8jUUaaINAdF7PX2sf9F1 SMoQ9gBydPMrg8/drZoHmOMq1XIpDy03zO1QR6O/GMTiggiorzREZfCq+DzpaX/07RoZ 5d0A== X-Gm-Message-State: ACrzQf118JK44pOxOjKGuXpR7nz4pkIQqISVA+YZ1FfSKXvX1d1Lb2Fu syYPu7a6waMMM8dMo5wNZI2xXBHNoPAgzd6p X-Google-Smtp-Source: AMsMyM7Z5vqlZqy5fRHJB0X8pJfRxiOkaNIUHdsp+IDiax0jjvjbsv3Nl0jPqc60AydiovlC6uYS4g== X-Received: by 2002:a05:6000:811:b0:236:622d:a7d6 with SMTP id bt17-20020a056000081100b00236622da7d6mr19178998wrb.258.1666903465241; Thu, 27 Oct 2022 13:44:25 -0700 (PDT) Received: from Mindolluin.ire.aristanetworks.com ([217.173.96.166]) by smtp.gmail.com with ESMTPSA id n3-20020a5d6b83000000b00236644228besm1968739wrx.40.2022.10.27.13.44.24 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Thu, 27 Oct 2022 13:44:24 -0700 (PDT) From: Dmitry Safonov To: linux-kernel@vger.kernel.org, David Ahern , Eric Dumazet Cc: Dmitry Safonov , Andy Lutomirski , Ard Biesheuvel , Bob Gilligan , Dan Carpenter , "David S. Miller" , Dmitry Safonov <0x7f454c46@gmail.com>, Eric Biggers , "Eric W. Biederman" , Francesco Ruggeri , Herbert Xu , Hideaki YOSHIFUJI , Ivan Delalande , Jakub Kicinski , Leonard Crestez , Paolo Abeni , Salam Noureddine , Shuah Khan , netdev@vger.kernel.org, linux-crypto@vger.kernel.org Subject: [PATCH v3 20/36] net/tcp: Add tcp_hash_fail() ratelimited logs Date: Thu, 27 Oct 2022 21:43:31 +0100 Message-Id: <20221027204347.529913-21-dima@arista.com> X-Mailer: git-send-email 2.38.1 In-Reply-To: <20221027204347.529913-1-dima@arista.com> References: <20221027204347.529913-1-dima@arista.com> MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: linux-crypto@vger.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 | 14 ++++++++++++-- include/net/tcp_ao.h | 27 +++++++++++++++++++++++++++ net/ipv4/tcp.c | 23 +++++++++++++---------- net/ipv4/tcp_ao.c | 7 +++++++ 4 files changed, 59 insertions(+), 12 deletions(-) diff --git a/include/net/tcp.h b/include/net/tcp.h index 72a1fe015c57..5512eb940441 100644 --- a/include/net/tcp.h +++ b/include/net/tcp.h @@ -2527,12 +2527,19 @@ 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 @@ -2555,11 +2562,14 @@ tcp_inbound_hash(struct sock *sk, const struct request_sock *req, lockdep_sock_is_held(sk)); NET_INC_STATS(sock_net(sk), LINUX_MIB_TCPAOREQUIRED); atomic64_inc(&ao_info->counters.ao_required); + tcp_hash_fail("AO hash is required, but not found", + family, skb, ""); return SKB_DROP_REASON_TCP_AONOTFOUND; } #endif 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 cc9925644118..b5ebc133399e 100644 --- a/include/net/tcp_ao.h +++ b/include/net/tcp_ao.h @@ -98,6 +98,33 @@ struct tcp_ao_info { atomic_t refcnt; /* Protects twsk destruction */ }; +#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 (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 7bfbb6330752..8d64bdec3af8 100644 --- a/net/ipv4/tcp.c +++ b/net/ipv4/tcp.c @@ -4523,7 +4523,6 @@ 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); struct tcp_sock *tp = tcp_sk(sk); struct tcp_md5sig_key *key; int genhash; @@ -4533,6 +4532,7 @@ 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; } @@ -4548,16 +4548,19 @@ 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 cdd4e4ed69cf..307b279d55f5 100644 --- a/net/ipv4/tcp_ao.c +++ b/net/ipv4/tcp_ao.c @@ -708,6 +708,8 @@ 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; } @@ -718,6 +720,7 @@ 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); @@ -744,6 +747,8 @@ 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; } @@ -838,6 +843,8 @@ 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; }