From patchwork Mon Sep 11 21:03:31 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Dmitry Safonov X-Patchwork-Id: 13380482 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 A2DDE1382 for ; Tue, 12 Sep 2023 02:05:13 +0000 (UTC) Received: from mail-ed1-x533.google.com (mail-ed1-x533.google.com [IPv6:2a00:1450:4864:20::533]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 4A2DD10CDDA for ; Mon, 11 Sep 2023 19:05:08 -0700 (PDT) Received: by mail-ed1-x533.google.com with SMTP id 4fb4d7f45d1cf-52bd9ddb741so6525029a12.0 for ; Mon, 11 Sep 2023 19:05:08 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=arista.com; s=google; t=1694484307; x=1695089107; 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=LBCs9GrljB/d271+d8dZbdlIHkK+9yQX+LQGkQ3IMdE=; b=XddR4geUbiCEGmrFPgmusiG84jsfVPcsGIChreJ6y+ReSjd1smukT2vGcKA1fGALwo SzkIsnVpkYMUAFlOEYmHKFMbYieReBSKc+gOOLK93/UujpUV2EHvNtGTs+gJQT0vLMEH aumKECOtGPLpJEag51I1PmE68IDzAOkLPvaFqf33wNIpwlwgPZtQoMzq0ygSRoDu5plS 7omYy4w6Jus9EKPriwLzKKfjRIeva6B/8APux7j5L1tS5tzaQdYHn95yaXiRmaddPXZW XTAxI050stFbBSXtWA5KI9Q5WAM7p2PxHNqlQ1Y8POKlZjDIK2KTobU2JmzUkqxJnx0y XpsQ== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20230601; t=1694484307; x=1695089107; 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=LBCs9GrljB/d271+d8dZbdlIHkK+9yQX+LQGkQ3IMdE=; b=EI40RxQuT5rznxKtF0ortxh6Aaey+7O2LKU5q5+8TESmNPNwxRXiYOEvHDbVHXd1js 9sfJq+ObfEyY1AXTJM9pJ5JUMmPFoJFwjDOc9FXgcsKNnjdMYr7LW2NcThZVrit904Ie A1HHmtuN6wvLybUKIUse0WlgERVxGf9EYeT7e+BmTwkpxM8WcjWYqvcnUam067e2g4cG jB+vtV1eiUNR2FlJUiPRZQGImD3uKkIPnj317gZjsQvz1tonIr2TX5Fy75Fm1OKx/uiH wU+YCPx/4eu/pZcadrQGhEe6djt8saffzKrg+6gS9HTMQdfH25PiL8/2s8l2khSzvxwC labQ== X-Gm-Message-State: AOJu0YyGGs51w+EyDobh1H7+MBdtEuA6uj8OVP+6onzYbeqj38b5UpZr 5nO1gbcSDHZpJSdAip2r92p18aaqaktRAxeLtDA= X-Google-Smtp-Source: AGHT+IFYupHTFh5woc8QBUpXS11rzTn+NeEuJmUUL/sZXL43C04GtjDkn8MrbdsL0dBOAqqGOo7jng== X-Received: by 2002:a05:600c:d5:b0:402:8c7b:ceea with SMTP id u21-20020a05600c00d500b004028c7bceeamr8894362wmm.30.1694466255213; Mon, 11 Sep 2023 14:04:15 -0700 (PDT) Received: from Mindolluin.ire.aristanetworks.com ([217.173.96.166]) by smtp.gmail.com with ESMTPSA id z20-20020a1c4c14000000b00402e942561fsm14261699wmf.38.2023.09.11.14.04.13 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Mon, 11 Sep 2023 14:04:14 -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 v11 net-next 11/23] net/tcp: Sign SYN-ACK segments with TCP-AO Date: Mon, 11 Sep 2023 22:03:31 +0100 Message-ID: <20230911210346.301750-12-dima@arista.com> X-Mailer: git-send-email 2.41.0 In-Reply-To: <20230911210346.301750-1-dima@arista.com> References: <20230911210346.301750-1-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 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 Acked-by: David Ahern --- include/net/tcp.h | 3 +++ include/net/tcp_ao.h | 6 +++++ net/ipv4/tcp_ao.c | 22 +++++++++++++++++ net/ipv4/tcp_ipv4.c | 1 + net/ipv4/tcp_output.c | 57 ++++++++++++++++++++++++++++++++++++++----- net/ipv6/tcp_ao.c | 22 +++++++++++++++++ net/ipv6/tcp_ipv6.c | 1 + 7 files changed, 106 insertions(+), 6 deletions(-) diff --git a/include/net/tcp.h b/include/net/tcp.h index 5daa2e98e6a3..56f4180443c7 100644 --- a/include/net/tcp.h +++ b/include/net/tcp.h @@ -2179,6 +2179,9 @@ struct tcp_request_sock_ops { struct request_sock *req, 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 d26d98f1b048..c922d2e31d08 100644 --- a/include/net/tcp_ao.h +++ b/include/net/tcp_ao.h @@ -144,6 +144,9 @@ int tcp_ao_prepare_reset(const struct sock *sk, struct sk_buff *skb, int tcp_v4_parse_ao(struct sock *sk, int cmd, 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); @@ -178,6 +181,9 @@ int tcp_v6_ao_hash_skb(char *ao_hash, struct tcp_ao_key *key, const struct sock *sk, const struct sk_buff *skb, 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 b114f3d901a0..0d8ea381300b 100644 --- a/net/ipv4/tcp_ao.c +++ b/net/ipv4/tcp_ao.c @@ -568,6 +568,28 @@ int tcp_v4_ao_hash_skb(char *ao_hash, struct tcp_ao_key *key, tkey, hash_offset, sne); } +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) +{ + void *hash_buf = NULL; + int err; + + hash_buf = kmalloc(tcp_ao_digest_size(ao_key), GFP_ATOMIC); + if (!hash_buf) + return -ENOMEM; + + err = tcp_v4_ao_calc_key_rsk(ao_key, hash_buf, req); + if (err) + goto out; + + err = tcp_ao_hash_skb(AF_INET, ao_hash, ao_key, req_to_sk(req), skb, + hash_buf, hash_offset, sne); +out: + kfree(hash_buf); + return err; +} + 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 9a4ffcc965f3..c40da33d988b 100644 --- a/net/ipv4/tcp_ipv4.c +++ b/net/ipv4/tcp_ipv4.c @@ -1675,6 +1675,7 @@ 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 44c97e6ddd50..c9d6decef443 100644 --- a/net/ipv4/tcp_output.c +++ b/net/ipv4/tcp_output.c @@ -900,6 +900,7 @@ static unsigned int tcp_synack_options(const struct sock *sk, unsigned int mss, struct sk_buff *skb, struct tcp_out_options *opts, const struct tcp_md5sig_key *md5, + const struct tcp_ao_key *ao, struct tcp_fastopen_cookie *foc, enum tcp_synack_type synack_type, struct sk_buff *syn_skb) @@ -921,6 +922,14 @@ static unsigned int tcp_synack_options(const struct sock *sk, ireq->tstamp_ok &= !ireq->sack_ok; } #endif +#ifdef CONFIG_TCP_AO + if (ao) { + opts->options |= OPTION_AO; + remaining -= tcp_ao_len(ao); + ireq->tstamp_ok &= !ireq->sack_ok; + } +#endif + WARN_ON_ONCE(md5 && ao); /* We always send an MSS option. */ opts->mss = mss; @@ -3727,6 +3736,7 @@ 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; @@ -3777,16 +3787,43 @@ 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, READ_ONCE(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, - 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); @@ -3806,7 +3843,7 @@ 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); @@ -3814,7 +3851,15 @@ 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 c9a6fa84f6ce..99753e12c08c 100644 --- a/net/ipv6/tcp_ao.c +++ b/net/ipv6/tcp_ao.c @@ -144,3 +144,25 @@ int tcp_v6_parse_ao(struct sock *sk, int cmd, { return tcp_parse_ao(sk, cmd, AF_INET6, optval, 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 *hash_buf = NULL; + int err; + + hash_buf = kmalloc(tcp_ao_digest_size(ao_key), GFP_ATOMIC); + if (!hash_buf) + return -ENOMEM; + + err = tcp_v6_ao_calc_key_rsk(ao_key, hash_buf, req); + if (err) + goto out; + + err = tcp_ao_hash_skb(AF_INET6, ao_hash, ao_key, req_to_sk(req), skb, + hash_buf, hash_offset, sne); +out: + kfree(hash_buf); + return err; +} diff --git a/net/ipv6/tcp_ipv6.c b/net/ipv6/tcp_ipv6.c index c060cd964f91..f57617d2921a 100644 --- a/net/ipv6/tcp_ipv6.c +++ b/net/ipv6/tcp_ipv6.c @@ -845,6 +845,7 @@ 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,