From patchwork Wed Feb 15 18:33:34 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Dmitry Safonov X-Patchwork-Id: 13142059 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 5795EC636D4 for ; Wed, 15 Feb 2023 18:36:34 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S230282AbjBOSgc (ORCPT ); Wed, 15 Feb 2023 13:36:32 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:49796 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S230345AbjBOSfn (ORCPT ); Wed, 15 Feb 2023 13:35:43 -0500 Received: from mail-wm1-x32e.google.com (mail-wm1-x32e.google.com [IPv6:2a00:1450:4864:20::32e]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 1A9793E09E for ; Wed, 15 Feb 2023 10:34:20 -0800 (PST) Received: by mail-wm1-x32e.google.com with SMTP id z13so14022400wmp.2 for ; Wed, 15 Feb 2023 10:34:20 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=arista.com; s=google; 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=+1FPQF1rXG4A/jQd/fcwDAUZHBiYXUCKbXLzG2fc0O0=; b=Et7AtUUbRO/Xw7WCuAirQIo9xegKW/u1xg1kzH6wy61oO+XbTefzV3XE5gahI+FJa0 w9ylBEopCWZwXrnML1c0eD3oEwIYTxq6vM5gM8N21hHWhyuCUmvAiC2JHZB9tr20sDgm 9vONNF8OaMv3eTyTp1Bk4PeUwzPBGraCjCzOurVCojhpptwW5hwCEej1ofP2g+00Dns4 sevoLJZSCCRzlGSg6M60JGihs8ek5MXcs4qdp42IXBI7fQbmh0F8QhB1n4q4JBBU0sEm 9DVPoN20n7gTaBdqhEUyunZHmpN7kCbeRL111YjBghHwJQQljipU4w6837yRXQHEo054 TpHA== 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:message-id:reply-to; bh=+1FPQF1rXG4A/jQd/fcwDAUZHBiYXUCKbXLzG2fc0O0=; b=zPGeHIy50u7ySEEyXw1jpDEGXSoSb04DDLITClbkdxphfAmYTDc6HODrg6keUK1f+V e/ZBR/0ZqStUFA5HPVQlkyeBkJ3JYFEmGNgk43BLHJaeFLDx5tRSw3RGqF4PB6/SApfZ OwcFGPind4Wy1szdojBksnO1l89ViqIMRuYpy1yaunrQG9u5kO7KbHl+IyfmjeskhahV KP2d0Lboe8IwMcjmQu9S+0A/9IeDGS8zBojmiLs6LLt/SWWQvUWb5zlhlddM9EfBZfTW JPxfxMNJR6XaR4o77B/JyzcSI5xK/Vvn9pp1ypU7of0cix92T9LtCJqtdkPAd8/ic8+X 1cLg== X-Gm-Message-State: AO0yUKUIKULWqU7TxJl9cVzGKbww2rFJ3CCxDFVwBtiZtvTaEcMvE1AT yHdBbKTTDTLPHy9IY7Jh0cloWQ== X-Google-Smtp-Source: AK7set93rTIM8qwwjULLBamnBHxDqE2tF5W14lVEubw1JuOeFBC7NA3ID38FUydivAcdzfZAL/Dlyw== X-Received: by 2002:a05:600c:5024:b0:3df:fcbd:3159 with SMTP id n36-20020a05600c502400b003dffcbd3159mr2597578wmr.3.1676486059627; Wed, 15 Feb 2023 10:34:19 -0800 (PST) Received: from Mindolluin.ire.aristanetworks.com ([217.173.96.166]) by smtp.gmail.com with ESMTPSA id s9-20020a05600c45c900b003e00c9888besm3196306wmo.30.2023.02.15.10.34.17 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Wed, 15 Feb 2023 10:34:18 -0800 (PST) From: Dmitry Safonov To: linux-kernel@vger.kernel.org, David Ahern , Eric Dumazet , Paolo Abeni , Jakub Kicinski , "David S. Miller" Cc: Dmitry Safonov , Andy Lutomirski , Ard Biesheuvel , Bob Gilligan , Dan Carpenter , David Laight , Dmitry Safonov <0x7f454c46@gmail.com>, Eric Biggers , "Eric W. Biederman" , Francesco Ruggeri , Herbert Xu , Hideaki YOSHIFUJI , Ivan Delalande , Leonard Crestez , Salam Noureddine , netdev@vger.kernel.org Subject: [PATCH v4 20/21] net/tcp-ao: Add static_key for TCP-AO Date: Wed, 15 Feb 2023 18:33:34 +0000 Message-Id: <20230215183335.800122-21-dima@arista.com> X-Mailer: git-send-email 2.39.1 In-Reply-To: <20230215183335.800122-1-dima@arista.com> References: <20230215183335.800122-1-dima@arista.com> MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: netdev@vger.kernel.org X-Patchwork-Delegate: kuba@kernel.org 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 --- include/net/tcp_ao.h | 2 ++ net/ipv4/tcp_ao.c | 17 +++++++++++++++++ net/ipv4/tcp_input.c | 42 ++++++++++++++++++++++++++++-------------- 3 files changed, 47 insertions(+), 14 deletions(-) diff --git a/include/net/tcp_ao.h b/include/net/tcp_ao.h index 04e3bcee05f7..253cf2719aed 100644 --- a/include/net/tcp_ao.h +++ b/include/net/tcp_ao.h @@ -131,6 +131,8 @@ do { \ #ifdef CONFIG_TCP_AO /* TCP-AO structures and functions */ +#include +extern struct static_key_false_deferred tcp_ao_needed; struct tcp4_ao_context { __be32 saddr; diff --git a/net/ipv4/tcp_ao.c b/net/ipv4/tcp_ao.c index 2c38e991ecbd..adb25e42f64a 100644 --- a/net/ipv4/tcp_ao.c +++ b/net/ipv4/tcp_ao.c @@ -17,6 +17,9 @@ #include #include +DEFINE_STATIC_KEY_DEFERRED_FALSE(tcp_ao_needed, HZ); +EXPORT_SYMBOL(tcp_ao_needed); + int tcp_ao_calc_traffic_key(struct tcp_ao_key *mkt, u8 *key, void *ctx, unsigned int len) { @@ -58,6 +61,9 @@ bool tcp_ao_ignore_icmp(struct sock *sk, int type, int code) struct tcp_ao_info *ao; bool ignore_icmp = false; + 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 @@ -196,6 +202,9 @@ struct tcp_ao_key *tcp_ao_do_lookup(const struct sock *sk, struct tcp_ao_key *key; struct tcp_ao_info *ao; + if (!static_branch_unlikely(&tcp_ao_needed.key)) + return NULL; + ao = rcu_dereference_check(tcp_sk(sk)->ao_info, lockdep_sock_is_held(sk)); if (!ao) @@ -283,6 +292,7 @@ void tcp_ao_destroy_sock(struct sock *sk, bool twsk) } kfree_rcu(ao, rcu); + static_branch_slow_dec_deferred(&tcp_ao_needed); } void tcp_ao_time_wait(struct tcp_timewait_sock *tcptw, struct tcp_sock *tp) @@ -1052,6 +1062,11 @@ int tcp_ao_copy_all_matching(const struct sock *sk, struct sock *newsk, goto free_and_exit; } + if (!static_key_fast_inc_not_disabled(&tcp_ao_needed.key.key)) { + ret = -EUSERS; + goto free_and_exit; + } + key_head = rcu_dereference(hlist_first_rcu(&new_ao->head)); first_key = hlist_entry_safe(key_head, struct tcp_ao_key, node); @@ -1607,6 +1622,8 @@ static int tcp_ao_add_cmd(struct sock *sk, unsigned short int family, tcp_ao_link_mkt(ao_info, key); if (first) { + if (!static_branch_inc(&tcp_ao_needed.key)) + goto err_free_sock; 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 9f23cab1e835..dd9ff507bbc9 100644 --- a/net/ipv4/tcp_input.c +++ b/net/ipv4/tcp_input.c @@ -3524,17 +3524,14 @@ static inline bool tcp_may_update_window(const struct tcp_sock *tp, (ack_seq == tp->snd_wl1 && nwin > tp->snd_wnd); } -/* 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 = ack - tp->snd_una; #ifdef CONFIG_TCP_AO struct tcp_ao_info *ao; -#endif - sock_owned_by_me((struct sock *)tp); - tp->bytes_acked += delta; -#ifdef CONFIG_TCP_AO + if (!static_branch_unlikely(&tcp_ao_needed.key)) + return; + ao = rcu_dereference_protected(tp->ao_info, lockdep_sock_is_held((struct sock *)tp)); if (ao) { @@ -3543,20 +3540,27 @@ static void tcp_snd_una_update(struct tcp_sock *tp, u32 ack) ao->snd_sne_seq = ack; } #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 = ack - tp->snd_una; + + sock_owned_by_me((struct sock *)tp); + tp->bytes_acked += delta; + tcp_snd_sne_update(tp, ack); tp->snd_una = ack; } -/* If we update tp->rcv_nxt, also update tp->bytes_received */ -static void tcp_rcv_nxt_update(struct tcp_sock *tp, u32 seq) +static void tcp_rcv_sne_update(struct tcp_sock *tp, u32 seq) { - u32 delta = seq - tp->rcv_nxt; #ifdef CONFIG_TCP_AO struct tcp_ao_info *ao; -#endif - sock_owned_by_me((struct sock *)tp); - tp->bytes_received += delta; -#ifdef CONFIG_TCP_AO + if (!static_branch_unlikely(&tcp_ao_needed.key)) + return; + ao = rcu_dereference_protected(tp->ao_info, lockdep_sock_is_held((struct sock *)tp)); if (ao) { @@ -3565,6 +3569,16 @@ static void tcp_rcv_nxt_update(struct tcp_sock *tp, u32 seq) ao->rcv_sne_seq = seq; } #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 = seq - tp->rcv_nxt; + + sock_owned_by_me((struct sock *)tp); + tp->bytes_received += delta; + tcp_rcv_sne_update(tp, seq); WRITE_ONCE(tp->rcv_nxt, seq); }