From patchwork Tue Jul 26 06:15:15 2022 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Leonard Crestez X-Patchwork-Id: 12928683 X-Patchwork-Delegate: herbert@gondor.apana.org.au 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 B7534C43334 for ; Tue, 26 Jul 2022 06:18:30 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S237713AbiGZGS2 (ORCPT ); Tue, 26 Jul 2022 02:18:28 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:58658 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S237712AbiGZGRJ (ORCPT ); Tue, 26 Jul 2022 02:17:09 -0400 Received: from mail-ed1-x531.google.com (mail-ed1-x531.google.com [IPv6:2a00:1450:4864:20::531]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 3933213F1D; Mon, 25 Jul 2022 23:16:03 -0700 (PDT) Received: by mail-ed1-x531.google.com with SMTP id c72so13618887edf.8; Mon, 25 Jul 2022 23:16:03 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20210112; h=from:to:cc:subject:date:message-id:in-reply-to:references :mime-version:content-transfer-encoding; bh=ETulC6nEJ4d/vSKkks3ENP+5YLpVysQwQ5oSeMKwg6Q=; b=Ji8cSXkqH6bWcXoaHI3pjFWXvqdIWBCKKqfpCa0ei2DWYEEXFLOHBZoI6c86unjuqV iurIZrt7VCaYd1inDW9e6JMFQZF7yIBxcd4uKM24/x36j07i/4YCoHoW77gK/0TnmMj2 50t97AarmROTlhOKzE/pvJNgQnCOF9IvfulM5z3ovUyQAcRaMTpxV2+bHY2wQb5JCvbv tQhH6izFhYGNLkRpIH5mMdZwTXN3qarIb7XUdJW/ZnePR3PgsH4g9G97dFVflnR+3/5y lw6vRBTpmrYQ/Ru1MuYFQaGgdnG3Qf/6+zC6WnaFbitLfTSyMDAATsBdFdNpdJZ9KTkH J5iA== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20210112; h=x-gm-message-state:from:to:cc:subject:date:message-id:in-reply-to :references:mime-version:content-transfer-encoding; bh=ETulC6nEJ4d/vSKkks3ENP+5YLpVysQwQ5oSeMKwg6Q=; b=YckidB3gt6jks0y4dVc+29y56p2eNoXZBfYoAFZEFa/4DU8pDwjb4O0stCUKAFGhS/ c23CZ7ez1pCWDRPM9FVtQZNx/c8hq71Mk03iv0FW/ftDMqbyAp94bGVyQH0/riXPmzxn nMSDvfgw1Ixx33IFRv6VgvIHXFfycHYuu1qYgfhoBVZdxmO3vWwkJcd9Du7ZQTCeS/hW pNUm8v1az1gt4PdqlJb0zj3gzW9dbBjWSol/l+WgXB/hL6MS7dnaR96Jk3w+323qSCha sp4fG7Nl9dfKvZ34fyb9DXw7r8xIE/SYdi+v1tKy/AXKIen/lXbvOJhFTyAh50kECAyB u8dw== X-Gm-Message-State: AJIora8BpC1j9EzoclD36aDknX4PuLHnpRMnNDRmhtWTawzv5TN3nCrx 7DEmgrcwI3tbnwggO6mYWPE= X-Google-Smtp-Source: AGRyM1ueJPDy9jnyqn6nC2GXXligKZpMB1XwE9AQFD00FdyTD8CCOUvbl5/9AKsc15cix4YtkiQpug== X-Received: by 2002:a05:6402:4381:b0:43b:cb55:ae3c with SMTP id o1-20020a056402438100b0043bcb55ae3cmr16231352edc.45.1658816162694; Mon, 25 Jul 2022 23:16:02 -0700 (PDT) Received: from localhost.localdomain ([2a04:241e:502:a080:2b68:36a:5a94:4ba1]) by smtp.gmail.com with ESMTPSA id l23-20020a056402345700b0043ba7df7a42sm8133067edc.26.2022.07.25.23.16.00 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Mon, 25 Jul 2022 23:16:02 -0700 (PDT) From: Leonard Crestez To: David Ahern , Eric Dumazet , Philip Paeps Cc: Dmitry Safonov <0x7f454c46@gmail.com>, Shuah Khan , "David S. Miller" , Herbert Xu , Kuniyuki Iwashima , Hideaki YOSHIFUJI , Jakub Kicinski , Yuchung Cheng , Francesco Ruggeri , Mat Martineau , Christoph Paasch , Ivan Delalande , Caowangbao , Priyaranjan Jha , netdev@vger.kernel.org, linux-crypto@vger.kernel.org, linux-kselftest@vger.kernel.org, linux-kernel@vger.kernel.org Subject: [PATCH v6 13/26] tcp: ipv4: Add AO signing for skb-less replies Date: Tue, 26 Jul 2022 09:15:15 +0300 Message-Id: X-Mailer: git-send-email 2.25.1 In-Reply-To: References: MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: linux-crypto@vger.kernel.org The code in tcp_v4_send_ack and tcp_v4_send_reset does not allocate a full skb so special handling is required for tcp-authopt handling. Signed-off-by: Leonard Crestez --- net/ipv4/tcp_authopt.c | 3 +- net/ipv4/tcp_ipv4.c | 84 ++++++++++++++++++++++++++++++++++++++++-- 2 files changed, 83 insertions(+), 4 deletions(-) diff --git a/net/ipv4/tcp_authopt.c b/net/ipv4/tcp_authopt.c index 2af6265041b4..f7635a37b972 100644 --- a/net/ipv4/tcp_authopt.c +++ b/net/ipv4/tcp_authopt.c @@ -966,10 +966,11 @@ static int tcp_v4_authopt_get_traffic_key_noskb(struct tcp_authopt_key_info *key u8 *traffic_key) { int err; struct tcp_authopt_alg_pool *pool; struct tcp_v4_authopt_context_data data; + char traffic_key_context_header[7] = "\x01TCP-AO"; BUILD_BUG_ON(sizeof(data) != 22); pool = tcp_authopt_get_kdf_pool(key); if (IS_ERR(pool)) @@ -982,11 +983,11 @@ static int tcp_v4_authopt_get_traffic_key_noskb(struct tcp_authopt_key_info *key if (err) goto out; // RFC5926 section 3.1.1.1 // Separate to keep alignment semi-sane - err = crypto_ahash_buf(pool->req, "\x01TCP-AO", 7); + err = crypto_ahash_buf(pool->req, traffic_key_context_header, 7); if (err) return err; data.saddr = saddr; data.daddr = daddr; data.sport = sport; diff --git a/net/ipv4/tcp_ipv4.c b/net/ipv4/tcp_ipv4.c index 93c564022748..0f76a03c007a 100644 --- a/net/ipv4/tcp_ipv4.c +++ b/net/ipv4/tcp_ipv4.c @@ -645,10 +645,50 @@ void tcp_v4_send_check(struct sock *sk, struct sk_buff *skb) __tcp_v4_send_check(skb, inet->inet_saddr, inet->inet_daddr); } EXPORT_SYMBOL(tcp_v4_send_check); +#ifdef CONFIG_TCP_AUTHOPT +/** tcp_v4_authopt_handle_reply - Insert TCPOPT_AUTHOPT if required + * + * returns number of bytes (always aligned to 4) or zero + */ +static int tcp_v4_authopt_handle_reply(const struct sock *sk, + struct sk_buff *skb, + __be32 *optptr, + struct tcphdr *th) +{ + struct tcp_authopt_info *info; + struct tcp_authopt_key_info *key_info; + u8 rnextkeyid; + + if (sk->sk_state == TCP_TIME_WAIT) + info = tcp_twsk(sk)->tw_authopt_info; + else + info = rcu_dereference_check(tcp_sk(sk)->authopt_info, lockdep_sock_is_held(sk)); + if (!info) + return 0; + key_info = __tcp_authopt_select_key(sk, info, sk, &rnextkeyid); + if (!key_info) + return 0; + *optptr = htonl((TCPOPT_AUTHOPT << 24) | + (TCPOLEN_AUTHOPT_OUTPUT << 16) | + (key_info->send_id << 8) | + (rnextkeyid)); + /* must update doff before signature computation */ + th->doff += TCPOLEN_AUTHOPT_OUTPUT / 4; + tcp_v4_authopt_hash_reply((char *)(optptr + 1), + info, + key_info, + ip_hdr(skb)->daddr, + ip_hdr(skb)->saddr, + th); + + return TCPOLEN_AUTHOPT_OUTPUT; +} +#endif + /* * This routine will send an RST to the other tcp. * * Someone asks: why I NEVER use socket parameters (TOS, TTL etc.) * for reset. @@ -660,10 +700,12 @@ EXPORT_SYMBOL(tcp_v4_send_check); * Exception: precedence violation. We do not implement it in any case. */ #ifdef CONFIG_TCP_MD5SIG #define OPTION_BYTES TCPOLEN_MD5SIG_ALIGNED +#elif defined(OPTION_BYTES_TCP_AUTHOPT) +#define OPTION_BYTES TCPOLEN_AUTHOPT_OUTPUT #else #define OPTION_BYTES sizeof(__be32) #endif static void tcp_v4_send_reset(const struct sock *sk, struct sk_buff *skb) @@ -713,12 +755,29 @@ static void tcp_v4_send_reset(const struct sock *sk, struct sk_buff *skb) memset(&arg, 0, sizeof(arg)); arg.iov[0].iov_base = (unsigned char *)&rep; arg.iov[0].iov_len = sizeof(rep.th); net = sk ? sock_net(sk) : dev_net(skb_dst(skb)->dev); -#ifdef CONFIG_TCP_MD5SIG +#if defined(CONFIG_TCP_MD5SIG) || defined(CONFIG_TCP_AUTHOPT) rcu_read_lock(); +#endif +#ifdef CONFIG_TCP_AUTHOPT + /* Unlike TCP-MD5 the signatures for TCP-AO depend on initial sequence + * numbers so we can only handle established and time-wait sockets. + */ + if (tcp_authopt_needed && sk && + sk->sk_state != TCP_NEW_SYN_RECV && + sk->sk_state != TCP_LISTEN) { + int tcp_authopt_ret = tcp_v4_authopt_handle_reply(sk, skb, rep.opt, &rep.th); + + if (tcp_authopt_ret) { + arg.iov[0].iov_len += tcp_authopt_ret; + goto skip_md5sig; + } + } +#endif +#ifdef CONFIG_TCP_MD5SIG hash_location = tcp_parse_md5sig_option(th); if (sk && sk_fullsock(sk)) { const union tcp_md5_addr *addr; int l3index; @@ -756,11 +815,10 @@ static void tcp_v4_send_reset(const struct sock *sk, struct sk_buff *skb) addr = (union tcp_md5_addr *)&ip_hdr(skb)->saddr; key = tcp_md5_do_lookup(sk1, l3index, addr, AF_INET); if (!key) goto out; - genhash = tcp_v4_md5_hash_skb(newhash, key, NULL, skb); if (genhash || memcmp(hash_location, newhash, 16) != 0) goto out; } @@ -776,10 +834,13 @@ static void tcp_v4_send_reset(const struct sock *sk, struct sk_buff *skb) tcp_v4_md5_hash_hdr((__u8 *) &rep.opt[1], key, ip_hdr(skb)->saddr, ip_hdr(skb)->daddr, &rep.th); } +#endif +#ifdef CONFIG_TCP_AUTHOPT +skip_md5sig: #endif /* Can't co-exist with TCPMD5, hence check rep.opt[0] */ if (rep.opt[0] == 0) { __be32 mrst = mptcp_reset_option(skb); @@ -833,12 +894,14 @@ static void tcp_v4_send_reset(const struct sock *sk, struct sk_buff *skb) sock_net_set(ctl_sk, &init_net); __TCP_INC_STATS(net, TCP_MIB_OUTSEGS); __TCP_INC_STATS(net, TCP_MIB_OUTRSTS); local_bh_enable(); -#ifdef CONFIG_TCP_MD5SIG +#if defined(CONFIG_TCP_MD5SIG) out: +#endif +#if defined(CONFIG_TCP_MD5SIG) || defined(CONFIG_TCP_AUTHOPT) rcu_read_unlock(); #endif } /* The code following below sending ACKs in SYN-RECV and TIME-WAIT states @@ -855,10 +918,12 @@ static void tcp_v4_send_ack(const struct sock *sk, struct { struct tcphdr th; __be32 opt[(TCPOLEN_TSTAMP_ALIGNED >> 2) #ifdef CONFIG_TCP_MD5SIG + (TCPOLEN_MD5SIG_ALIGNED >> 2) +#elif defined(CONFIG_TCP_AUTHOPT) + + (TCPOLEN_AUTHOPT_OUTPUT >> 2) #endif ]; } rep; struct net *net = sock_net(sk); struct ip_reply_arg arg; @@ -886,10 +951,23 @@ static void tcp_v4_send_ack(const struct sock *sk, rep.th.seq = htonl(seq); rep.th.ack_seq = htonl(ack); rep.th.ack = 1; rep.th.window = htons(win); +#ifdef CONFIG_TCP_AUTHOPT + if (tcp_authopt_needed) { + int aoret, offset = (tsecr) ? 3 : 0; + + aoret = tcp_v4_authopt_handle_reply(sk, skb, &rep.opt[offset], &rep.th); + if (aoret) { + arg.iov[0].iov_len += aoret; +#ifdef CONFIG_TCP_MD5SIG + key = NULL; +#endif + } + } +#endif #ifdef CONFIG_TCP_MD5SIG if (key) { int offset = (tsecr) ? 3 : 0; rep.opt[offset++] = htonl((TCPOPT_NOP << 24) |