From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-15.7 required=3.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,FREEMAIL_FORGED_FROMDOMAIN,FREEMAIL_FROM, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER,INCLUDES_PATCH, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,USER_AGENT_GIT autolearn=unavailable autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 7DC64C433F5 for ; Tue, 21 Sep 2021 16:17:50 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 69D666115A for ; Tue, 21 Sep 2021 16:17:50 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S234470AbhIUQTN (ORCPT ); Tue, 21 Sep 2021 12:19:13 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:33580 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S234526AbhIUQSk (ORCPT ); Tue, 21 Sep 2021 12:18:40 -0400 Received: from mail-ed1-x52a.google.com (mail-ed1-x52a.google.com [IPv6:2a00:1450:4864:20::52a]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id E1399C061575; Tue, 21 Sep 2021 09:17:09 -0700 (PDT) Received: by mail-ed1-x52a.google.com with SMTP id eg28so53600344edb.1; Tue, 21 Sep 2021 09:17:09 -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=tn4CP0rVaPBCvAa1AgJpDJmjYYuaun+JN2VJXULQEUA=; b=PplHb97KK0YpRW+4V+pSfbmFVxwSeVGHIpgptNQgAf/kL3vRQda4R0IpqH/Ypy7/AP Bc1V2G4vtYXlwWXlrMslzdVwT2DMUVWLLJ0bPUqhkEGxusP1ATbO23UPwWhqzoUfMdGo EIx025OkPm+UxzfuZRQbePSCuVHZgdRzsAINMMLUq/jMkh7cuwfBRrJL7seKn/Cp5W1W CTEyNoLU3KjcoXLRxQZmFa4CMbFRsSCXk/fYhofPdOTdLJrGnSymBXtyFMES+JW+Nyg8 wGTqFMqXO1JTUFOf5DAS3YltvDyzlm9uPtOK2NG/rJnnoFBBDGqOR0IANUt2+EM461Wa FUGw== 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=tn4CP0rVaPBCvAa1AgJpDJmjYYuaun+JN2VJXULQEUA=; b=uF52XMbstMsBPEpiC2Q5YWQPZp5Aos9kA3rwZJeEZW0fviw5YA7Kj2pXHBYDknjxI/ UvU1QdUaQvmCOPfuM5TlQaMgSUDr9R3OsL8XI0cgrGfE64nyfHASn5TaNrTBTCjwXXWU fS66IGGCzS/S3CgAb5ZPjPn6ar39EOg+KQxBB7wCI77ElvIliVNAWo/tYenWkNFdAKwL dFVZhsobT7hBijse8SvSZNlBfSiE5wTWDISKJZCrm+9IW0Q293vbp/X9VIFpvIcHr7Nn DInIuFOF3qP8oL54zNqUE9ggj0LWTsrqQ2zrDwhxMSxGLlNSOYIDt/nE2HvCft5ckQ/j ea7w== X-Gm-Message-State: AOAM530nrGe07h42PEwtSqUSOnYhSoZhl3RKdR37K9qdrW5uRe7WAq1A 0W48xg42Q7ZGT13UHogvE0M= X-Google-Smtp-Source: ABdhPJy7x5BquSLn2axABT7ln/2JxDM53KIIbdLKZXjE++QbzVTDUQG6dr4Qa5NTgAfczj061HnQaQ== X-Received: by 2002:a05:6402:2913:: with SMTP id ee19mr35884241edb.332.1632240935288; Tue, 21 Sep 2021 09:15:35 -0700 (PDT) Received: from pinky.lan ([2a04:241e:502:1df0:b065:9bdf:4016:277]) by smtp.gmail.com with ESMTPSA id kx17sm7674075ejc.51.2021.09.21.09.15.33 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Tue, 21 Sep 2021 09:15:34 -0700 (PDT) From: Leonard Crestez To: Dmitry Safonov <0x7f454c46@gmail.com>, David Ahern , Shuah Khan Cc: Eric Dumazet , "David S. Miller" , Herbert Xu , Kuniyuki Iwashima , Hideaki YOSHIFUJI , Jakub Kicinski , Yuchung Cheng , Francesco Ruggeri , Mat Martineau , Christoph Paasch , Ivan Delalande , Priyaranjan Jha , Menglong Dong , netdev@vger.kernel.org, linux-crypto@vger.kernel.org, linux-kselftest@vger.kernel.org, linux-kernel@vger.kernel.org Subject: [PATCH 11/19] tcp: authopt: Add support for signing skb-less replies Date: Tue, 21 Sep 2021 19:14:54 +0300 Message-Id: <7301a3b6ce1c5c282f10c2cc45a1409dee8abd86.1632240523.git.cdleonard@gmail.com> X-Mailer: git-send-email 2.25.1 In-Reply-To: References: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit Precedence: bulk List-ID: X-Mailing-List: linux-crypto@vger.kernel.org This is required because tcp ipv4 sometimes sends replies without allocating a full skb that can be signed by tcp authopt. Handle this with additional code in tcp authopt. Signed-off-by: Leonard Crestez --- include/net/tcp_authopt.h | 7 ++ net/ipv4/tcp_authopt.c | 147 ++++++++++++++++++++++++++++++++++++++ 2 files changed, 154 insertions(+) diff --git a/include/net/tcp_authopt.h b/include/net/tcp_authopt.h index 422f0034d32b..b012eaaf416f 100644 --- a/include/net/tcp_authopt.h +++ b/include/net/tcp_authopt.h @@ -81,10 +81,17 @@ static inline struct tcp_authopt_key_info *tcp_authopt_select_key( } int tcp_authopt_hash( char *hash_location, struct tcp_authopt_key_info *key, struct sock *sk, struct sk_buff *skb); +int tcp_v4_authopt_hash_reply( + char *hash_location, + struct tcp_authopt_info *info, + struct tcp_authopt_key_info *key, + __be32 saddr, + __be32 daddr, + struct tcphdr *th); int __tcp_authopt_openreq(struct sock *newsk, const struct sock *oldsk, struct request_sock *req); static inline int tcp_authopt_openreq( struct sock *newsk, const struct sock *oldsk, struct request_sock *req) diff --git a/net/ipv4/tcp_authopt.c b/net/ipv4/tcp_authopt.c index 41f844d5d49a..756182401a3b 100644 --- a/net/ipv4/tcp_authopt.c +++ b/net/ipv4/tcp_authopt.c @@ -798,10 +798,74 @@ static int tcp_authopt_get_traffic_key(struct sock *sk, out: tcp_authopt_put_kdf_shash(key, kdf_tfm); return err; } +struct tcp_v4_authopt_context_data { + __be32 saddr; + __be32 daddr; + __be16 sport; + __be16 dport; + __be32 sisn; + __be32 disn; + __be16 digestbits; +} __packed; + +static int tcp_v4_authopt_get_traffic_key_noskb( + struct tcp_authopt_key_info *key, + __be32 saddr, + __be32 daddr, + __be16 sport, + __be16 dport, + __be32 sisn, + __be32 disn, + u8 *traffic_key) +{ + int err; + struct crypto_shash *kdf_tfm; + SHASH_DESC_ON_STACK(desc, kdf_tfm); + struct tcp_v4_authopt_context_data data; + BUILD_BUG_ON(sizeof(data) != 22); + + kdf_tfm = tcp_authopt_get_kdf_shash(key); + if (IS_ERR(kdf_tfm)) + return PTR_ERR(kdf_tfm); + + err = tcp_authopt_setkey(kdf_tfm, key); + if (err) + goto out; + + desc->tfm = kdf_tfm; + err = crypto_shash_init(desc); + if (err) + goto out; + + // RFC5926 section 3.1.1.1 + // Separate to keep alignment semi-sane + err = crypto_shash_update(desc, "\x01TCP-AO", 7); + if (err) + return err; + data.saddr = saddr; + data.daddr = daddr; + data.sport = sport; + data.dport = dport; + data.sisn = sisn; + data.disn = disn; + data.digestbits = htons(crypto_shash_digestsize(desc->tfm) * 8); + + err = crypto_shash_update(desc, (u8*)&data, sizeof(data)); + if (err) + goto out; + err = crypto_shash_final(desc, traffic_key); + if (err) + goto out; + +out: + tcp_authopt_put_kdf_shash(key, kdf_tfm); + return err; +} + static int crypto_shash_update_zero(struct shash_desc *desc, int len) { u8 zero = 0; int i, err; @@ -1122,10 +1186,93 @@ int tcp_authopt_hash(char *hash_location, memcpy(hash_location, macbuf, TCP_AUTHOPT_MACLEN); return 0; } +/** + * tcp_v4_authopt_hash_hdr - Hash tcp+ipv4 header without SKB + * + * The key must come from tcp_authopt_select_key. + */ +int tcp_v4_authopt_hash_reply(char *hash_location, + struct tcp_authopt_info *info, + struct tcp_authopt_key_info *key, + __be32 saddr, + __be32 daddr, + struct tcphdr *th) +{ + struct crypto_shash *mac_tfm; + u8 macbuf[TCP_AUTHOPT_MAXMACBUF]; + u8 traffic_key[TCP_AUTHOPT_MAX_TRAFFIC_KEY_LEN]; + SHASH_DESC_ON_STACK(desc, tfm); + __be32 sne = 0; + int err; + + /* Call special code path for computing traffic key without skb + * This can be called from tcp_v4_reqsk_send_ack so caching would be + * difficult here. + */ + err = tcp_v4_authopt_get_traffic_key_noskb( + key, + saddr, + daddr, + th->source, + th->dest, + htonl(info->src_isn), + htonl(info->dst_isn), + traffic_key); + if (err) + goto out_err_traffic_key; + + /* Init mac shash */ + mac_tfm = tcp_authopt_get_mac_shash(key); + if (IS_ERR(mac_tfm)) + return PTR_ERR(mac_tfm); + err = crypto_shash_setkey(mac_tfm, traffic_key, key->alg->traffic_key_len); + if (err) + goto out_err; + + desc->tfm = mac_tfm; + err = crypto_shash_init(desc); + if (err) + return err; + + err = crypto_shash_update(desc, (u8 *)&sne, 4); + if (err) + return err; + + err = tcp_authopt_hash_tcp4_pseudoheader(desc, saddr, daddr, th->doff * 4); + if (err) + return err; + + // TCP header with checksum set to zero. Caller ensures this. + if (WARN_ON_ONCE(th->check != 0)) + goto out_err; + err = crypto_shash_update(desc, (u8 *)th, sizeof(*th)); + if (err) + goto out_err; + + // TCP options + err = tcp_authopt_hash_opts(desc, th, !(key->flags & TCP_AUTHOPT_KEY_EXCLUDE_OPTS)); + if (err) + goto out_err; + + err = crypto_shash_final(desc, macbuf); + if (err) + goto out_err; + memcpy(hash_location, macbuf, TCP_AUTHOPT_MACLEN); + + tcp_authopt_put_mac_shash(key, mac_tfm); + return 0; + +out_err: + tcp_authopt_put_mac_shash(key, mac_tfm); +out_err_traffic_key: + memset(hash_location, 0, TCP_AUTHOPT_MACLEN); + return err; +} + static struct tcp_authopt_key_info *tcp_authopt_lookup_recv(struct sock *sk, struct sk_buff *skb, struct tcp_authopt_info *info, int recv_id) { -- 2.25.1