From patchwork Fri May 12 20:23:01 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Dmitry Safonov X-Patchwork-Id: 13239667 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 21CF220989 for ; Fri, 12 May 2023 20:23:37 +0000 (UTC) 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 15FFC5B8F for ; Fri, 12 May 2023 13:23:35 -0700 (PDT) Received: by mail-wm1-x329.google.com with SMTP id 5b1f17b1804b1-3f42c865534so47734625e9.2 for ; Fri, 12 May 2023 13:23:35 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=arista.com; s=google; t=1683923014; x=1686515014; 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=6zHkHl9dKWlQNtq7+YmDrNpmWpjjJ+psG+94ruMNHlg=; b=ZJ1VZhLASmC1sR/TTA0PvTmcP6Ks/yCHIcFRPoLkyKubRM2N2YOadz+orwKCRu8mnc kqF8StT7wEJIMf/KdjZiHO53h1I/XzPFS1cXIB1TcldUtzq8CMKUhvPMWKU948TmNkvx y+HcRxGiTJ5BiXU33pkPvJ7etJHet2fM0m1K8Lyny3uW+5pT+TCLUtbxKYKF1kFGrKGm ScCqDiOXeMeu7D2/S/ml0Z5oFtNVpsYWea1K0BUfYQODqSRza67Po1Q4ACvKT7k0vwco JXB6rOvQrn/FALxyCVPHz9vgqCxjnTP++Bsxvd/AcJRu4aHX39Jtsf9HnjwNE1y2wLP8 HrKA== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20221208; t=1683923014; x=1686515014; 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=6zHkHl9dKWlQNtq7+YmDrNpmWpjjJ+psG+94ruMNHlg=; b=ShyFX6Qql34Pw8w6QLcBkZ48hGUrqGTPUxxfHAkp/gEuCIx38NOTWIZnpuoYFHhIRA MvZ3WMe6uTrR2Ao8X98Lopx1VIOlyOXBghd0QlnxhizaKHnrNrXV/quL8dwIwT+RWH7z waWZxjsQKjQWZpQT6hhXvHmtdHZ7KW3KfR7CW+5DnMpg9PNFgzw2UOeccspzeEcOmCj0 A6bMKFfYX6zDsk6GM1SusiFUQVBkqDiXqdawJTItNrzvKVm1idvfiaIA3YVLH+xekHbz SeOJGGzidjJa8HBATb/wpDdD8C7l8weKGP0/Z1D2nhTBhhsNfO8lYXdqBudIO8gplmN4 cxfQ== X-Gm-Message-State: AC+VfDxihLtX6rYbCINIs+E61geKkTJ6hJLS5MUQwltPsVnW8rwxBwIj 6NqwMZJacoLmxZ7JrRghsf0kwQ== X-Google-Smtp-Source: ACHHUZ6U5npR24X86iJAjKa98f+w1+nEkNTCgTD9Fy7bKw4BWKWLb8SSdey0UkhqOwi1kkeNi25qVw== X-Received: by 2002:a05:600c:248:b0:3f4:2cf3:a53c with SMTP id 8-20020a05600c024800b003f42cf3a53cmr11318983wmj.22.1683923014563; Fri, 12 May 2023 13:23:34 -0700 (PDT) Received: from Mindolluin.ire.aristanetworks.com ([217.173.96.166]) by smtp.gmail.com with ESMTPSA id n9-20020a05600c294900b003f423508c6bsm17304527wmd.44.2023.05.12.13.23.33 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Fri, 12 May 2023 13:23:34 -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 11/21] net/tcp: Sign SYN-ACK segments with TCP-AO Date: Fri, 12 May 2023 21:23:01 +0100 Message-Id: <20230512202311.2845526-12-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 Similarly to RST segments, wire SYN-ACKs to TCP-AO. tcp_rsk_used_ao() is handy here to check if the request socket used AO and needs a signature on the outgoing segments. 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 | 4 ++++ include/net/tcp_ao.h | 6 ++++++ net/ipv4/tcp_ao.c | 14 +++++++++++++ net/ipv4/tcp_ipv4.c | 1 + net/ipv4/tcp_output.c | 48 +++++++++++++++++++++++++++++++++++++------ net/ipv6/tcp_ao.c | 15 ++++++++++++++ net/ipv6/tcp_ipv6.c | 1 + 7 files changed, 83 insertions(+), 6 deletions(-) diff --git a/include/net/tcp.h b/include/net/tcp.h index 08b7a603f90d..433e9c83e4ae 100644 --- a/include/net/tcp.h +++ b/include/net/tcp.h @@ -2149,6 +2149,10 @@ struct tcp_request_sock_ops { int sndid, int rcvid); int (*ao_calc_key)(struct tcp_ao_key *mkt, u8 *key, struct request_sock *sk); + int (*ao_synack_hash)(char *ao_hash, struct tcp_ao_key *mkt, + struct request_sock *req, + const struct sk_buff *skb, + int hash_offset, u32 sne); #endif #ifdef CONFIG_SYN_COOKIES __u32 (*cookie_init_seq)(const struct sk_buff *skb, diff --git a/include/net/tcp_ao.h b/include/net/tcp_ao.h index 2faeaa3a857a..eacb4925f4a9 100644 --- a/include/net/tcp_ao.h +++ b/include/net/tcp_ao.h @@ -145,6 +145,9 @@ int tcp_ao_hash_hdr(unsigned short family, char *ao_hash, int tcp_v4_parse_ao(struct sock *sk, int optname, sockptr_t optval, int optlen); struct tcp_ao_key *tcp_v4_ao_lookup(const struct sock *sk, struct sock *addr_sk, int sndid, int rcvid); +int tcp_v4_ao_synack_hash(char *ao_hash, struct tcp_ao_key *mkt, + struct request_sock *req, const struct sk_buff *skb, + int hash_offset, u32 sne); int tcp_v4_ao_calc_key_sk(struct tcp_ao_key *mkt, u8 *key, const struct sock *sk, __be32 sisn, __be32 disn, bool send); @@ -180,6 +183,9 @@ int tcp_v6_ao_hash_skb(char *ao_hash, struct tcp_ao_key *key, const u8 *tkey, int hash_offset, u32 sne); int tcp_v6_parse_ao(struct sock *sk, int cmd, sockptr_t optval, int optlen); +int tcp_v6_ao_synack_hash(char *ao_hash, struct tcp_ao_key *ao_key, + struct request_sock *req, const struct sk_buff *skb, + int hash_offset, u32 sne); void tcp_ao_finish_connect(struct sock *sk, struct sk_buff *skb); void tcp_ao_connect_init(struct sock *sk); void tcp_ao_syncookie(struct sock *sk, const struct sk_buff *skb, diff --git a/net/ipv4/tcp_ao.c b/net/ipv4/tcp_ao.c index 92485f7bc4cd..bfd944fa4483 100644 --- a/net/ipv4/tcp_ao.c +++ b/net/ipv4/tcp_ao.c @@ -554,6 +554,20 @@ int tcp_v4_ao_hash_skb(char *ao_hash, struct tcp_ao_key *key, } EXPORT_SYMBOL_GPL(tcp_v4_ao_hash_skb); +int tcp_v4_ao_synack_hash(char *ao_hash, struct tcp_ao_key *ao_key, + struct request_sock *req, const struct sk_buff *skb, + int hash_offset, u32 sne) +{ + char traffic_key[TCP_AO_MAX_HASH_SIZE] __tcp_ao_key_align; + + tcp_v4_ao_calc_key_rsk(ao_key, traffic_key, req); + + tcp_ao_hash_skb(AF_INET, ao_hash, ao_key, req_to_sk(req), skb, + traffic_key, hash_offset, sne); + + return 0; +} + struct tcp_ao_key *tcp_v4_ao_lookup_rsk(const struct sock *sk, struct request_sock *req, int sndid, int rcvid) diff --git a/net/ipv4/tcp_ipv4.c b/net/ipv4/tcp_ipv4.c index 40c7c568a84e..ca28517644d5 100644 --- a/net/ipv4/tcp_ipv4.c +++ b/net/ipv4/tcp_ipv4.c @@ -1696,6 +1696,7 @@ const struct tcp_request_sock_ops tcp_request_sock_ipv4_ops = { #ifdef CONFIG_TCP_AO .ao_lookup = tcp_v4_ao_lookup_rsk, .ao_calc_key = tcp_v4_ao_calc_key_rsk, + .ao_synack_hash = tcp_v4_ao_synack_hash, #endif #ifdef CONFIG_SYN_COOKIES .cookie_init_seq = cookie_v4_init_sequence, diff --git a/net/ipv4/tcp_output.c b/net/ipv4/tcp_output.c index 5344e6564b56..f055ef225c37 100644 --- a/net/ipv4/tcp_output.c +++ b/net/ipv4/tcp_output.c @@ -3638,6 +3638,7 @@ struct sk_buff *tcp_make_synack(const struct sock *sk, struct dst_entry *dst, struct inet_request_sock *ireq = inet_rsk(req); const struct tcp_sock *tp = tcp_sk(sk); struct tcp_md5sig_key *md5 = NULL; + struct tcp_ao_key *ao_key = NULL; struct tcp_out_options opts; struct sk_buff *skb; int tcp_header_size; @@ -3688,16 +3689,43 @@ struct sk_buff *tcp_make_synack(const struct sock *sk, struct dst_entry *dst, tcp_rsk(req)->snt_synack = tcp_skb_timestamp_us(skb); } -#ifdef CONFIG_TCP_MD5SIG +#if defined(CONFIG_TCP_MD5SIG) || defined(CONFIG_TCP_AO) rcu_read_lock(); - md5 = tcp_rsk(req)->af_specific->req_md5_lookup(sk, req_to_sk(req)); #endif + if (tcp_rsk_used_ao(req)) { +#ifdef CONFIG_TCP_AO + u8 maclen = tcp_rsk(req)->maclen; + u8 keyid = tcp_rsk(req)->ao_keyid; + + ao_key = tcp_sk(sk)->af_specific->ao_lookup(sk, req_to_sk(req), + keyid, -1); + /* If there is no matching key - avoid sending anything, + * especially usigned segments. It could try harder and lookup + * for another peer-matching key, but the peer has requested + * ao_keyid (RFC5925 RNextKeyID), so let's keep it simple here. + */ + if (unlikely(!ao_key || tcp_ao_maclen(ao_key) != maclen)) { + rcu_read_unlock(); + skb_dst_drop(skb); + kfree_skb(skb); + net_warn_ratelimited("TCP-AO: the keyid %u with maclen %u|%u from SYN packet is not present - not sending SYNACK\n", + keyid, maclen, + ao_key ? tcp_ao_maclen(ao_key) : 0); + return NULL; + } +#endif + } else { +#ifdef CONFIG_TCP_MD5SIG + md5 = tcp_rsk(req)->af_specific->req_md5_lookup(sk, + req_to_sk(req)); +#endif + } skb_set_hash(skb, tcp_rsk(req)->txhash, PKT_HASH_TYPE_L4); /* bpf program will be interested in the tcp_flags */ TCP_SKB_CB(skb)->tcp_flags = TCPHDR_SYN | TCPHDR_ACK; tcp_header_size = tcp_synack_options(sk, req, mss, skb, &opts, md5, - NULL, foc, synack_type, - syn_skb) + sizeof(*th); + ao_key, foc, synack_type, syn_skb) + + sizeof(*th); skb_push(skb, tcp_header_size); skb_reset_transport_header(skb); @@ -3717,7 +3745,7 @@ struct sk_buff *tcp_make_synack(const struct sock *sk, struct dst_entry *dst, /* RFC1323: The window in SYN & SYN/ACK segments is never scaled. */ th->window = htons(min(req->rsk_rcv_wnd, 65535U)); - tcp_options_write(th, NULL, NULL, &opts, NULL); + tcp_options_write(th, NULL, tcp_rsk(req), &opts, ao_key); th->doff = (tcp_header_size >> 2); TCP_INC_STATS(sock_net(sk), TCP_MIB_OUTSEGS); @@ -3725,7 +3753,15 @@ struct sk_buff *tcp_make_synack(const struct sock *sk, struct dst_entry *dst, /* Okay, we have all we need - do the md5 hash if needed */ if (md5) tcp_rsk(req)->af_specific->calc_md5_hash(opts.hash_location, - md5, req_to_sk(req), skb); + md5, req_to_sk(req), skb); +#endif +#ifdef CONFIG_TCP_AO + if (ao_key) + tcp_rsk(req)->af_specific->ao_synack_hash(opts.hash_location, + ao_key, req, skb, + opts.hash_location - (u8 *)th, 0); +#endif +#if defined(CONFIG_TCP_MD5SIG) || defined(CONFIG_TCP_AO) rcu_read_unlock(); #endif diff --git a/net/ipv6/tcp_ao.c b/net/ipv6/tcp_ao.c index 17acb2fd5182..bc032e441ef8 100644 --- a/net/ipv6/tcp_ao.c +++ b/net/ipv6/tcp_ao.c @@ -128,3 +128,18 @@ int tcp_v6_parse_ao(struct sock *sk, int cmd, return tcp_parse_ao(sk, cmd, AF_INET6, optval, optlen); } EXPORT_SYMBOL_GPL(tcp_v6_parse_ao); + +int tcp_v6_ao_synack_hash(char *ao_hash, struct tcp_ao_key *ao_key, + struct request_sock *req, const struct sk_buff *skb, + int hash_offset, u32 sne) +{ + char traffic_key[TCP_AO_MAX_HASH_SIZE] __tcp_ao_key_align; + + tcp_v6_ao_calc_key_rsk(ao_key, traffic_key, req); + + tcp_ao_hash_skb(AF_INET6, ao_hash, ao_key, req_to_sk(req), skb, + traffic_key, hash_offset, sne); + + return 0; +} +EXPORT_SYMBOL_GPL(tcp_v6_ao_synack_hash); diff --git a/net/ipv6/tcp_ipv6.c b/net/ipv6/tcp_ipv6.c index 386160140208..b2f17d6ec5c3 100644 --- a/net/ipv6/tcp_ipv6.c +++ b/net/ipv6/tcp_ipv6.c @@ -849,6 +849,7 @@ const struct tcp_request_sock_ops tcp_request_sock_ipv6_ops = { #ifdef CONFIG_TCP_AO .ao_lookup = tcp_v6_ao_lookup_rsk, .ao_calc_key = tcp_v6_ao_calc_key_rsk, + .ao_synack_hash = tcp_v6_ao_synack_hash, #endif #ifdef CONFIG_SYN_COOKIES .cookie_init_seq = cookie_v6_init_sequence,