From patchwork Wed Dec 8 11:37:30 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Leonard Crestez X-Patchwork-Id: 12664223 X-Patchwork-Delegate: kuba@kernel.org 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 65101C433EF for ; Wed, 8 Dec 2021 11:40:14 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S233110AbhLHLnn (ORCPT ); Wed, 8 Dec 2021 06:43:43 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:57660 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S232753AbhLHLm7 (ORCPT ); Wed, 8 Dec 2021 06:42:59 -0500 Received: from mail-ed1-x52e.google.com (mail-ed1-x52e.google.com [IPv6:2a00:1450:4864:20::52e]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 39231C0698FD; Wed, 8 Dec 2021 03:38:24 -0800 (PST) Received: by mail-ed1-x52e.google.com with SMTP id g14so7312430edb.8; Wed, 08 Dec 2021 03:38:24 -0800 (PST) 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=WRLWa8lRaYgTnoCjf0MCIMJlWF3rpMYgtwIN9Z8LM1M=; b=eWiVFueOszF5uuwc8NXtDO5jeEUqecM6jiRT8TM7BBH/Czzfmdlhpexxhhqd3yRUDS 2HalnVoyBjgkdIwzgJZIRjtFjsGo4O5HyhAUyIEPW+UDOyD4B6rBfbFf8vzoJGUmvtSa vrLAIJbUGlrEmhAnYgH618y8OHkumZOMCqZPQMcJqwRiAk2NVI8odEc5X5zINlsLwAsP uzmYkOxxQMPJDr+56WwqINHznzz9KCbeVg5fVXu5s+R6Yh13iPUa+eY41SY1FEu01d0k Wyo2nEfu9yDGoL180yjmw8ShaegBI6vFkigi/gizBCw0o/yDYjRIslwFUdi1m5bt3oTs cWgg== 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=WRLWa8lRaYgTnoCjf0MCIMJlWF3rpMYgtwIN9Z8LM1M=; b=k9mwLpCLWeCjcy9mzqGsjgSywCpM5M2OgIff6sqqvdynqOVGq+ngv+20vBFFz6n4w5 G3WVKtJq9F5dt5NVl3dHJbgtzzjLVu5uGVQdiIVe8s9vDhdhARkLuFReMGOTCOi+4fZX Sw0PdMDVpV4tEdYc2t4is1jCyUU72KQB8hNKDUSuV3T4tqSPewIwATfffMfl9AV0lodq ZOu1JY+dokzY9B5OP8YZU4qn/n2o6zOuw5Hi4nAZpFa6yAFIl4EJebFGg6VQeI3/nddf kz+a8bIuCZ+nwLWC5gby0Z62Ob573evbbJui2kfNT6DBWE15UOE2bUiidmt7NBqqm5CC ocEQ== X-Gm-Message-State: AOAM533mzfgfcSOAsDpA9rO36iYEhGAA4tF5cb/aQFMm0Ir4f9DhbELb F8ri8W9OAzOXvJuTVqj+vyQ= X-Google-Smtp-Source: ABdhPJwr8rmdlj27hRPGAsQjoGELSadhS6i8HUm884Suw3+dYk9TiTfbmYbQWUsLZY4xr8WmDMzHlw== X-Received: by 2002:aa7:df9a:: with SMTP id b26mr18034715edy.107.1638963502765; Wed, 08 Dec 2021 03:38:22 -0800 (PST) Received: from ponky.lan ([2a04:241e:501:3870:3c9f:e05b:4dff:43ba]) by smtp.gmail.com with ESMTPSA id g11sm1883810edz.53.2021.12.08.03.38.21 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Wed, 08 Dec 2021 03:38:22 -0800 (PST) From: Leonard Crestez To: David Ahern , Dmitry Safonov <0x7f454c46@gmail.com>, Eric Dumazet Cc: Francesco Ruggeri , Shuah Khan , "David S. Miller" , Herbert Xu , Kuniyuki Iwashima , Hideaki YOSHIFUJI , Jakub Kicinski , Yuchung Cheng , Mat Martineau , Christoph Paasch , Ivan Delalande , Priyaranjan Jha , netdev@vger.kernel.org, linux-crypto@vger.kernel.org, linux-kselftest@vger.kernel.org, linux-kernel@vger.kernel.org Subject: [PATCH v3 15/18] tcp: authopt: Add prefixlen support Date: Wed, 8 Dec 2021 13:37:30 +0200 Message-Id: <9ea8e4b68d98e22e0e7e818e64bbc86f73d46c1e.1638962992.git.cdleonard@gmail.com> X-Mailer: git-send-email 2.25.1 In-Reply-To: References: MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: netdev@vger.kernel.org X-Patchwork-Delegate: kuba@kernel.org This allows making a key apply to an addr/prefix instead of just the full addr. This is enabled through a custom flag, default behavior is still full address match. This is equivalent to TCP_MD5SIG_FLAG_PREFIX from TCP_MD5SIG and has the same use-cases. Signed-off-by: Leonard Crestez --- include/net/tcp_authopt.h | 2 ++ include/uapi/linux/tcp.h | 10 ++++++ net/ipv4/tcp_authopt.c | 67 ++++++++++++++++++++++++++++++++++++--- 3 files changed, 75 insertions(+), 4 deletions(-) diff --git a/include/net/tcp_authopt.h b/include/net/tcp_authopt.h index e57bc732f737..6c50395c0412 100644 --- a/include/net/tcp_authopt.h +++ b/include/net/tcp_authopt.h @@ -41,10 +41,12 @@ struct tcp_authopt_key_info { u8 keylen; /** @key: Same as &tcp_authopt_key.key */ u8 key[TCP_AUTHOPT_MAXKEYLEN]; /** @l3index: Same as &tcp_authopt_key.ifindex */ int l3index; + /** @prefix: Length of addr match (default full) */ + int prefixlen; /** @addr: Same as &tcp_authopt_key.addr */ struct sockaddr_storage addr; /** @alg: Algorithm implementation matching alg_id */ struct tcp_authopt_alg_imp *alg; }; diff --git a/include/uapi/linux/tcp.h b/include/uapi/linux/tcp.h index ed27feb93b0e..b1063e1e1b9f 100644 --- a/include/uapi/linux/tcp.h +++ b/include/uapi/linux/tcp.h @@ -403,18 +403,21 @@ struct tcp_authopt { * @TCP_AUTHOPT_KEY_EXCLUDE_OPTS: Exclude TCP options from signature * @TCP_AUTHOPT_KEY_ADDR_BIND: Key only valid for `tcp_authopt.addr` * @TCP_AUTHOPT_KEY_IFINDEX: Key only valid for `tcp_authopt.ifindex` * @TCP_AUTHOPT_KEY_NOSEND: Key invalid for send (expired) * @TCP_AUTHOPT_KEY_NORECV: Key invalid for recv (expired) + * @TCP_AUTHOPT_KEY_PREFIXLEN: Valid value in `tcp_authopt.prefixlen`, otherwise + * match full address length */ enum tcp_authopt_key_flag { TCP_AUTHOPT_KEY_DEL = (1 << 0), TCP_AUTHOPT_KEY_EXCLUDE_OPTS = (1 << 1), TCP_AUTHOPT_KEY_ADDR_BIND = (1 << 2), TCP_AUTHOPT_KEY_IFINDEX = (1 << 3), TCP_AUTHOPT_KEY_NOSEND = (1 << 4), TCP_AUTHOPT_KEY_NORECV = (1 << 5), + TCP_AUTHOPT_KEY_PREFIXLEN = (1 << 6), }; /** * enum tcp_authopt_alg - Algorithms for TCP Authentication Option */ @@ -465,10 +468,17 @@ struct tcp_authopt_key { * connections through this interface. Interface must be an vrf master. * * This is similar to `tcp_msg5sig.tcpm_ifindex` */ int ifindex; + /** + * @prefixlen: length of prefix to match + * + * Without the TCP_AUTHOPT_KEY_PREFIXLEN flag this is ignored and a full + * address match is performed. + */ + int prefixlen; }; /* setsockopt(fd, IPPROTO_TCP, TCP_ZEROCOPY_RECEIVE, ...) */ #define TCP_RECEIVE_ZEROCOPY_FLAG_TLB_CLEAN_HINT 0x1 diff --git a/net/ipv4/tcp_authopt.c b/net/ipv4/tcp_authopt.c index 946d598258b1..5069bb80054e 100644 --- a/net/ipv4/tcp_authopt.c +++ b/net/ipv4/tcp_authopt.c @@ -1,8 +1,13 @@ // SPDX-License-Identifier: GPL-2.0-or-later +#include "linux/in6.h" +#include "linux/inetdevice.h" #include "linux/net.h" +#include "linux/socket.h" +#include "linux/tcp.h" +#include "net/ipv6.h" #include #include #include #include @@ -219,10 +224,14 @@ static bool tcp_authopt_key_match_exact(struct tcp_authopt_key_info *info, return false; if ((info->flags & TCP_AUTHOPT_KEY_IFINDEX) != (key->flags & TCP_AUTHOPT_KEY_IFINDEX)) return false; if ((info->flags & TCP_AUTHOPT_KEY_IFINDEX) && info->l3index != key->ifindex) return false; + if ((info->flags & TCP_AUTHOPT_KEY_PREFIXLEN) != (key->flags & TCP_AUTHOPT_KEY_PREFIXLEN)) + return false; + if ((info->flags & TCP_AUTHOPT_KEY_PREFIXLEN) && info->prefixlen != key->prefixlen) + return false; if ((info->flags & TCP_AUTHOPT_KEY_ADDR_BIND) != (key->flags & TCP_AUTHOPT_KEY_ADDR_BIND)) return false; if (info->flags & TCP_AUTHOPT_KEY_ADDR_BIND) if (!ipvx_addr_match(&info->addr, &key->addr)) return false; @@ -236,17 +245,20 @@ static bool tcp_authopt_key_match_skb_addr(struct tcp_authopt_key_info *key, u16 keyaf = key->addr.ss_family; struct iphdr *iph = (struct iphdr *)skb_network_header(skb); if (keyaf == AF_INET && iph->version == 4) { struct sockaddr_in *key_addr = (struct sockaddr_in *)&key->addr; + u32 mask = inet_make_mask(key->prefixlen); - return iph->saddr == key_addr->sin_addr.s_addr; + return (iph->saddr & mask) == key_addr->sin_addr.s_addr; } else if (keyaf == AF_INET6 && iph->version == 6) { struct ipv6hdr *ip6h = (struct ipv6hdr *)skb_network_header(skb); struct sockaddr_in6 *key_addr = (struct sockaddr_in6 *)&key->addr; - return ipv6_addr_equal(&ip6h->saddr, &key_addr->sin6_addr); + return ipv6_prefix_equal(&ip6h->saddr, + &key_addr->sin6_addr, + key->prefixlen); } /* This actually happens with ipv6-mapped-ipv4-addresses * IPv6 listen sockets will be asked to validate ipv4 packets. */ @@ -262,16 +274,19 @@ static bool tcp_authopt_key_match_sk_addr(struct tcp_authopt_key_info *key, if (keyaf != addr_sk->sk_family) return false; if (keyaf == AF_INET) { struct sockaddr_in *key_addr = (struct sockaddr_in *)&key->addr; + u32 mask = inet_make_mask(key->prefixlen); - return addr_sk->sk_daddr == key_addr->sin_addr.s_addr; + return (addr_sk->sk_daddr & mask) == key_addr->sin_addr.s_addr; } else if (keyaf == AF_INET6) { struct sockaddr_in6 *key_addr = (struct sockaddr_in6 *)&key->addr; - return ipv6_addr_equal(&addr_sk->sk_v6_daddr, &key_addr->sin6_addr); + return ipv6_prefix_equal(&addr_sk->sk_v6_daddr, + &key_addr->sin6_addr, + key->prefixlen); } return false; } @@ -296,10 +311,16 @@ static bool better_key_match(struct tcp_authopt_key_info *old, struct tcp_authop /* l3index always overrides non-l3index */ if (old->l3index && new->l3index == 0) return false; if (old->l3index == 0 && new->l3index) return true; + /* Full address match overrides match by prefixlen */ + if (!(new->flags & TCP_AUTHOPT_KEY_PREFIXLEN) && (old->flags & TCP_AUTHOPT_KEY_PREFIXLEN)) + return false; + /* Longer prefixes are better matches */ + if (new->prefixlen > old->prefixlen) + return true; return false; } static struct tcp_authopt_key_info *tcp_authopt_lookup_send(struct tcp_authopt_info *info, @@ -596,20 +617,31 @@ void tcp_authopt_clear(struct sock *sk) #define TCP_AUTHOPT_KEY_KNOWN_FLAGS ( \ TCP_AUTHOPT_KEY_DEL | \ TCP_AUTHOPT_KEY_EXCLUDE_OPTS | \ TCP_AUTHOPT_KEY_ADDR_BIND | \ TCP_AUTHOPT_KEY_IFINDEX | \ + TCP_AUTHOPT_KEY_PREFIXLEN | \ TCP_AUTHOPT_KEY_NOSEND | \ TCP_AUTHOPT_KEY_NORECV) +static bool ipv6_addr_is_prefix(struct in6_addr *addr, int plen) +{ + struct in6_addr copy; + + ipv6_addr_prefix_copy(©, addr, plen); + + return !!memcmp(©, addr, sizeof(*addr)); +} + int tcp_set_authopt_key(struct sock *sk, sockptr_t optval, unsigned int optlen) { struct tcp_authopt_key opt; struct tcp_authopt_info *info; struct tcp_authopt_key_info *key_info, *old_key_info; struct tcp_authopt_alg_imp *alg; int l3index = 0; + int prefixlen; int err; sock_owned_by_me(sk); err = check_sysctl_tcp_authopt(); if (err) @@ -641,10 +673,36 @@ int tcp_set_authopt_key(struct sock *sk, sockptr_t optval, unsigned int optlen) if (opt.flags & TCP_AUTHOPT_KEY_ADDR_BIND) { if (sk->sk_family != opt.addr.ss_family) return -EINVAL; } + /* check prefixlen */ + if (opt.flags & TCP_AUTHOPT_KEY_PREFIXLEN) { + prefixlen = opt.prefixlen; + if (sk->sk_family == AF_INET) { + if (prefixlen < 0 || prefixlen > 32) + return -EINVAL; + if (((struct sockaddr_in *)&opt.addr)->sin_addr.s_addr & + ~inet_make_mask(prefixlen)) + return -EINVAL; + } + if (sk->sk_family == AF_INET6) { + if (prefixlen < 0 || prefixlen > 128) + return -EINVAL; + if (!ipv6_addr_is_prefix(&((struct sockaddr_in6 *)&opt.addr)->sin6_addr, + prefixlen)) + return -EINVAL; + } + } else { + if (sk->sk_family == AF_INET) + prefixlen = 32; + else if (sk->sk_family == AF_INET6) + prefixlen = 128; + else + return -EINVAL; + } + /* Initialize tcp_authopt_info if not already set */ info = __tcp_authopt_info_get_or_create(sk); if (IS_ERR(info)) return PTR_ERR(info); @@ -688,10 +746,11 @@ int tcp_set_authopt_key(struct sock *sk, sockptr_t optval, unsigned int optlen) key_info->alg = alg; key_info->keylen = opt.keylen; memcpy(key_info->key, opt.key, opt.keylen); memcpy(&key_info->addr, &opt.addr, sizeof(key_info->addr)); key_info->l3index = l3index; + key_info->prefixlen = prefixlen; hlist_add_head_rcu(&key_info->node, &info->head); return 0; }