From patchwork Mon Sep 5 07:05:48 2022 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Leonard Crestez X-Patchwork-Id: 602793 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 C5557ECAAA1 for ; Mon, 5 Sep 2022 07:07:41 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S237188AbiIEHHk (ORCPT ); Mon, 5 Sep 2022 03:07:40 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:46862 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S237193AbiIEHGh (ORCPT ); Mon, 5 Sep 2022 03:06:37 -0400 Received: from mail-ej1-x631.google.com (mail-ej1-x631.google.com [IPv6:2a00:1450:4864:20::631]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id DD1173ED79; Mon, 5 Sep 2022 00:06:34 -0700 (PDT) Received: by mail-ej1-x631.google.com with SMTP id y3so15185804ejc.1; Mon, 05 Sep 2022 00:06:34 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20210112; h=content-transfer-encoding:mime-version:references:in-reply-to :message-id:date:subject:cc:to:from:from:to:cc:subject:date; bh=c9EVZYRmZFEa+mhI7nELrKf80ztjjaC5E4TvNzLk0hk=; b=qXDP91ZMnGXSkqgmELTTNkM03q+vPnY/QEWA8IBCFQYtuLUW3gt2MF3awXZpP4XObt 5GiSyUAfXtp7UN+MafwHjLaNg9Yl5FwrUOQkVMIxZT/DXHm9iJhab3RNeGG1l+1Oa1HI NSrQmIE2zGw1Od1EppJyeTxged/RIvZ9DU49Wa4d7atCZKyGTIAygMmwga6RkxsF79W7 Dkp4DxuKol/mQkgFWCvHZoL3OTK8iiSwusMVBk1mu8RF4gt+LEaIwiWRGpgBLmyV8u31 ulvG/ZCFLBKzy77G4dU4d0Sh9GWsYdeyde/FbprG9PA4rmbAU9AGVL/6Nw+ReOvc1zHZ rh9Q== 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; bh=c9EVZYRmZFEa+mhI7nELrKf80ztjjaC5E4TvNzLk0hk=; b=A7O6oAL/PjttHQpRDuA8QMScezmOrL3Ehs+4sAodp04cvkxg0Tez2FCRCWYEa56Qf0 FQ4+bBXcMwbrVC0p54OvlRt4muk9cbwDWlS95I/l96x7yZGRykf7VOOqOp/KGUc9poFs GxO/gWS+ggAW4UDZltH1qrrjWte09JUMW29ClmgFMaSCcf3RXJ8DchyE3Npm/Zhixz8z eP2SGrJ59fJW8kIue9nLb2kDnHMmWSR/PoJnTAb0KvbRVO5pwNtVn46jrZ9j0Zed0OnG g1BmFwlUH6tqRrjPgEt7WjxURrfPgxrgnQ4mupclPtE6TLYO+6LCH3lpd26VjXY9Dn0j PnYw== X-Gm-Message-State: ACgBeo3sWYh9HL/u7nlHW54igsJm2V6o6kHKXn/h2kw74brNRk1MtYGv 5a+yyzZ1H97qDB4ZsXa7i2I= X-Google-Smtp-Source: AA6agR6XlT72Tv3kXZulS0I74rBjQTk8N7IbyKF6NibaasDcfCrRkQvnAZJuHGwc21fGjpnGMsscqw== X-Received: by 2002:a17:907:9495:b0:73c:b19e:ce06 with SMTP id dm21-20020a170907949500b0073cb19ece06mr34532700ejc.559.1662361594449; Mon, 05 Sep 2022 00:06:34 -0700 (PDT) Received: from localhost.localdomain ([2a04:241e:502:a080:40ec:9f50:387:3cfb]) by smtp.gmail.com with ESMTPSA id n27-20020a056402515b00b0043cf2e0ce1csm5882775edd.48.2022.09.05.00.06.32 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Mon, 05 Sep 2022 00:06:33 -0700 (PDT) From: Leonard Crestez To: David Ahern , Eric Dumazet , Dmitry Safonov <0x7f454c46@gmail.com> Cc: Francesco Ruggeri , Salam Noureddine , Philip Paeps , Shuah Khan , "David S. Miller" , Herbert Xu , Kuniyuki Iwashima , Hideaki YOSHIFUJI , Jakub Kicinski , Yuchung Cheng , 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 v8 12/26] tcp: ipv4: Add AO signing for skb-less replies Date: Mon, 5 Sep 2022 10:05:48 +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 0260173cd546..0672a3bf5686 100644 --- a/net/ipv4/tcp_authopt.c +++ b/net/ipv4/tcp_authopt.c @@ -962,10 +962,11 @@ 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)) @@ -978,11 +979,11 @@ 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 05939e696dd6..198912f3f533 100644 --- a/net/ipv4/tcp_ipv4.c +++ b/net/ipv4/tcp_ipv4.c @@ -664,10 +664,50 @@ 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. @@ -679,10 +719,12 @@ 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) @@ -732,12 +774,29 @@ 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; @@ -775,11 +834,10 @@ 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; } @@ -795,10 +853,13 @@ 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); @@ -852,12 +913,14 @@ 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 @@ -874,10 +937,12 @@ 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; @@ -905,10 +970,23 @@ 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) |