From nobody Mon Feb 9 01:16:42 2026 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 A5989C001E0 for ; Wed, 2 Aug 2023 17:29:50 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S233574AbjHBR3t (ORCPT ); Wed, 2 Aug 2023 13:29:49 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:48242 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S233733AbjHBR2H (ORCPT ); Wed, 2 Aug 2023 13:28:07 -0400 Received: from mail-wm1-x32a.google.com (mail-wm1-x32a.google.com [IPv6:2a00:1450:4864:20::32a]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 3DDD43AB1 for ; Wed, 2 Aug 2023 10:27:41 -0700 (PDT) Received: by mail-wm1-x32a.google.com with SMTP id 5b1f17b1804b1-3fb4146e8fcso866765e9.0 for ; Wed, 02 Aug 2023 10:27:41 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=arista.com; s=google; t=1690997259; x=1691602059; 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=0VkWLLbFOMdgX3//vCiGhsq4HWyieVY0WWn7M0ZehJM=; b=FU5+KdH/zbgnZZOesp8pjIsc7mBZtJakfUvGIOsa32u/8AchIiNa4YnKDqyEcwa8gh GdkqLmHwzqYqh1th7vYNOJlSijNJ9oVNRnEj6wB+M0mqvxEUjleXrUEGjNjG8AowPVWZ NCKzKfoT++39lrMp5PCC5VV72a3JnaE4Ni1tBfB5ZMGoMNhWbLhqd1MgF1h3pz3cay/R n+r7Pyq51tT87GZ2E8AKc90k7B0uPWXb3x2+gwDZmyeRoxmpthfGh54I07W8iFbXYgkw Lu1cl09wHB6W8KsmbY7/kl6p0MY7TnIau+/5DlrLg18KBon92lcXMfLTSWqDOyjpKwY5 TwAw== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20221208; t=1690997259; x=1691602059; 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=0VkWLLbFOMdgX3//vCiGhsq4HWyieVY0WWn7M0ZehJM=; b=GMPMo5QlbsBgaSICajl5m5KzLd73N6ZS45zUZtVUbYWSBoVxfrH/Hbgf65Y+4G2rqn cdAAKtdZB5CRXf9r+3Eq6+y5vb/oJG1AZwUiPkkJoakb6sEVSoIX68Wo+5qVYK6RHynD xtE790/cXQVaIc0dpJkQPulolydGzmvsh3WHvr3YCTNwJvV/Du76hcKKWKhkKj2QSeAB 6Z0kbankxc+dcRI4w1sB5QGZ62Bw6IP05le1UAjFtvSaVzNET1hK/GSinThNU09WJLfi lzocqTdCFUKNVuM3DoLLSIaRg+CxTmHu2jq1eRvxMr/Bqpshb8j8TmYft8Hb76VyhTWu dtnw== X-Gm-Message-State: ABy/qLY6TopXxp5cuHUiCURKdg/VTo7fUWqnO4E8GCSe3jRlfOJzekyl 9KQIgSXct5j4ukrn1RyZct5bBg== X-Google-Smtp-Source: APBJJlGJIJnwiCkcF21GYG4C1P9cvYRVz/L5Bgf78O5AdDasmA0DX7KGPxM8bs4bM4A8t8Rg4oWb8A== X-Received: by 2002:a1c:4b17:0:b0:3fb:c060:9698 with SMTP id y23-20020a1c4b17000000b003fbc0609698mr6108651wma.5.1690997259114; Wed, 02 Aug 2023 10:27:39 -0700 (PDT) Received: from Mindolluin.ire.aristanetworks.com ([217.173.96.166]) by smtp.gmail.com with ESMTPSA id q5-20020a1ce905000000b003fbc0a49b57sm2221770wmc.6.2023.08.02.10.27.37 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Wed, 02 Aug 2023 10:27:38 -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 , Salam Noureddine , "Tetreault, Francois" , netdev@vger.kernel.org Subject: [PATCH v9 net-next 20/23] net/tcp: Add static_key for TCP-AO Date: Wed, 2 Aug 2023 18:26:47 +0100 Message-ID: <20230802172654.1467777-21-dima@arista.com> X-Mailer: git-send-email 2.41.0 In-Reply-To: <20230802172654.1467777-1-dima@arista.com> References: <20230802172654.1467777-1-dima@arista.com> MIME-Version: 1.0 Content-Transfer-Encoding: quoted-printable Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Type: text/plain; charset="utf-8" Similarly to TCP-MD5, add a static key to TCP-AO that is patched out when there are no keys on a machine and dynamically enabled with the first setsockopt(TCP_AO) adds a key on any socket. The static key is as well dynamically disabled later when the socket is destructed. The lifetime of enabled static key here is the same as ao_info: it is enabled on allocation, passed over from full socket to twsk and destructed when ao_info is scheduled for destruction. Signed-off-by: Dmitry Safonov Acked-by: David Ahern --- include/net/tcp.h | 3 +++ include/net/tcp_ao.h | 2 ++ net/ipv4/tcp_ao.c | 22 +++++++++++++++++++++ net/ipv4/tcp_input.c | 46 +++++++++++++++++++++++++++++--------------- 4 files changed, 57 insertions(+), 16 deletions(-) diff --git a/include/net/tcp.h b/include/net/tcp.h index 85e0f0b50261..b90ef7090dd6 100644 --- a/include/net/tcp.h +++ b/include/net/tcp.h @@ -2612,6 +2612,9 @@ static inline bool tcp_ao_required(struct sock *sk, c= onst void *saddr, struct tcp_ao_info *ao_info; struct tcp_ao_key *ao_key; =20 + if (!static_branch_unlikely(&tcp_ao_needed.key)) + return false; + ao_info =3D rcu_dereference_check(tcp_sk(sk)->ao_info, lockdep_sock_is_held(sk)); if (!ao_info) diff --git a/include/net/tcp_ao.h b/include/net/tcp_ao.h index bd616e070eda..63cfbbc620a2 100644 --- a/include/net/tcp_ao.h +++ b/include/net/tcp_ao.h @@ -151,6 +151,8 @@ do { \ =20 #ifdef CONFIG_TCP_AO /* TCP-AO structures and functions */ +#include +extern struct static_key_false_deferred tcp_ao_needed; =20 struct tcp4_ao_context { __be32 saddr; diff --git a/net/ipv4/tcp_ao.c b/net/ipv4/tcp_ao.c index afe509bb1d16..0cdc6c327a5f 100644 --- a/net/ipv4/tcp_ao.c +++ b/net/ipv4/tcp_ao.c @@ -17,6 +17,8 @@ #include #include =20 +DEFINE_STATIC_KEY_DEFERRED_FALSE(tcp_ao_needed, HZ); + int tcp_ao_calc_traffic_key(struct tcp_ao_key *mkt, u8 *key, void *ctx, unsigned int len, struct tcp_sigpool *hp) { @@ -50,6 +52,9 @@ bool tcp_ao_ignore_icmp(struct sock *sk, int type, int co= de) bool ignore_icmp =3D false; struct tcp_ao_info *ao; =20 + if (!static_branch_unlikely(&tcp_ao_needed.key)) + return false; + /* RFC5925, 7.8: * >> A TCP-AO implementation MUST default to ignore incoming ICMPv4 * messages of Type 3 (destination unreachable), Codes 2-4 (protocol @@ -188,6 +193,9 @@ static struct tcp_ao_key *__tcp_ao_do_lookup(const stru= ct sock *sk, struct tcp_ao_key *key; struct tcp_ao_info *ao; =20 + if (!static_branch_unlikely(&tcp_ao_needed.key)) + return NULL; + ao =3D rcu_dereference_check(tcp_sk(sk)->ao_info, lockdep_sock_is_held(sk)); if (!ao) @@ -279,6 +287,7 @@ void tcp_ao_destroy_sock(struct sock *sk, bool twsk) } =20 kfree_rcu(ao, rcu); + static_branch_slow_dec_deferred(&tcp_ao_needed); } =20 void tcp_ao_time_wait(struct tcp_timewait_sock *tcptw, struct tcp_sock *tp) @@ -1133,6 +1142,11 @@ int tcp_ao_copy_all_matching(const struct sock *sk, = struct sock *newsk, goto free_and_exit; } =20 + if (!static_key_fast_inc_not_disabled(&tcp_ao_needed.key.key)) { + ret =3D -EUSERS; + goto free_and_exit; + } + key_head =3D rcu_dereference(hlist_first_rcu(&new_ao->head)); first_key =3D hlist_entry_safe(key_head, struct tcp_ao_key, node); =20 @@ -1560,6 +1574,10 @@ static int tcp_ao_add_cmd(struct sock *sk, unsigned = short int family, =20 tcp_ao_link_mkt(ao_info, key); if (first) { + if (!static_branch_inc(&tcp_ao_needed.key)) { + ret =3D -EUSERS; + goto err_free_sock; + } sk_gso_disable(sk); rcu_assign_pointer(tcp_sk(sk)->ao_info, ao_info); } @@ -1828,6 +1846,10 @@ static int tcp_ao_info_cmd(struct sock *sk, unsigned= short int family, if (new_rnext) WRITE_ONCE(ao_info->rnext_key, new_rnext); if (first) { + if (!static_branch_inc(&tcp_ao_needed.key)) { + err =3D -EUSERS; + goto out; + } sk_gso_disable(sk); rcu_assign_pointer(tcp_sk(sk)->ao_info, ao_info); } diff --git a/net/ipv4/tcp_input.c b/net/ipv4/tcp_input.c index 4b37e82ab612..777f5f5f721d 100644 --- a/net/ipv4/tcp_input.c +++ b/net/ipv4/tcp_input.c @@ -3528,41 +3528,55 @@ static inline bool tcp_may_update_window(const stru= ct tcp_sock *tp, (ack_seq =3D=3D tp->snd_wl1 && nwin > tp->snd_wnd); } =20 -/* If we update tp->snd_una, also update tp->bytes_acked */ -static void tcp_snd_una_update(struct tcp_sock *tp, u32 ack) +static void tcp_snd_sne_update(struct tcp_sock *tp, u32 ack) { - u32 delta =3D ack - tp->snd_una; #ifdef CONFIG_TCP_AO struct tcp_ao_info *ao; -#endif =20 - sock_owned_by_me((struct sock *)tp); - tp->bytes_acked +=3D delta; -#ifdef CONFIG_TCP_AO + if (!static_branch_unlikely(&tcp_ao_needed.key)) + return; + ao =3D rcu_dereference_protected(tp->ao_info, lockdep_sock_is_held((struct sock *)tp)); if (ao && ack < tp->snd_una) ao->snd_sne++; #endif +} + +/* If we update tp->snd_una, also update tp->bytes_acked */ +static void tcp_snd_una_update(struct tcp_sock *tp, u32 ack) +{ + u32 delta =3D ack - tp->snd_una; + + sock_owned_by_me((struct sock *)tp); + tp->bytes_acked +=3D delta; + tcp_snd_sne_update(tp, ack); tp->snd_una =3D ack; } =20 +static void tcp_rcv_sne_update(struct tcp_sock *tp, u32 seq) +{ +#ifdef CONFIG_TCP_AO + struct tcp_ao_info *ao; + + if (!static_branch_unlikely(&tcp_ao_needed.key)) + return; + + ao =3D rcu_dereference_protected(tp->ao_info, + lockdep_sock_is_held((struct sock *)tp)); + if (ao && seq < tp->rcv_nxt) + ao->rcv_sne++; +#endif +} + /* If we update tp->rcv_nxt, also update tp->bytes_received */ static void tcp_rcv_nxt_update(struct tcp_sock *tp, u32 seq) { u32 delta =3D seq - tp->rcv_nxt; -#ifdef CONFIG_TCP_AO - struct tcp_ao_info *ao; -#endif =20 sock_owned_by_me((struct sock *)tp); tp->bytes_received +=3D delta; -#ifdef CONFIG_TCP_AO - ao =3D rcu_dereference_protected(tp->ao_info, - lockdep_sock_is_held((struct sock *)tp)); - if (ao && seq < tp->rcv_nxt) - ao->rcv_sne++; -#endif + tcp_rcv_sne_update(tp, seq); WRITE_ONCE(tp->rcv_nxt, seq); } =20 --=20 2.41.0