From patchwork Fri May 12 20:23:10 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Dmitry Safonov X-Patchwork-Id: 13239677 X-Patchwork-Delegate: kuba@kernel.org Received: from lindbergh.monkeyblade.net (lindbergh.monkeyblade.net [23.128.96.19]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 6886B21088 for ; Fri, 12 May 2023 20:23:51 +0000 (UTC) Received: from mail-wm1-x335.google.com (mail-wm1-x335.google.com [IPv6:2a00:1450:4864:20::335]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 6C4DD6EBF for ; Fri, 12 May 2023 13:23:47 -0700 (PDT) Received: by mail-wm1-x335.google.com with SMTP id 5b1f17b1804b1-3f41dceb9d4so74866645e9.1 for ; Fri, 12 May 2023 13:23:47 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=arista.com; s=google; t=1683923027; x=1686515027; 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=x6Ihe7mNatsp+aOBLmS5S5MBjAGFIM7G6AEhsvQUkDE=; b=AT1PVRgDN9K3+i4NT5nQEEajvdd+yPqr86IJa8GRXRDhaPTGANL/7ShanTNEjHIzS1 EjLVHmIEzKV3nr6sPUFu+HTyLAkq0+PPeJGaHWd/yVqL6U+i5mCt3yUAxuKpaIrvKMWa Qs9bBUSMt0VTNk8eJ+xDd7/G2YIfCNz3z/5opMBGZLOFh0r4iPQRQNx7pVCiG7vdxU/Y 42aScuPnxUSSIDl0Z96MhfLyjUMGCRSlN0K+ADJzM/RJ2WWNUrIhOcogyZs3FOacritr +Uvnngi2URrrzMpIetNG7kZHeqwfjYCvnWuGIbAz7ALyfN9y+8ntuT2EcbklGNEcszMO 0TuQ== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20221208; t=1683923027; x=1686515027; 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=x6Ihe7mNatsp+aOBLmS5S5MBjAGFIM7G6AEhsvQUkDE=; b=ljVy4aqvL1mod6GjM8oSMWtZpp/pWP97nClCD7IiPTHEsuBTv0K9K4aTdY35JeMw1S x8ium4NnczPVnK/QPIQmkLVs7A4TkRzfGSSJxs+NqmCQLKQXJWtuyPew9QetN+XN6pzP Qb2VnmBh85s7NCSzujzurk/B12xOYWCUpkKmtfZFqis2WHuSW2oRcAxieRyjabbFJaWN 9dR5+oJpVXfYfLZo018z+dTv5ojEwaNw8Ppqcjwyl+d/Sn7JDAe71RjGIxKh9eSgG9pP UIYTOJQEon0vNUdGC4kucP7onZuMhWcGAUIRYYzjazrJkNz/827UkIkXND42lW+yZBth D4Jg== X-Gm-Message-State: AC+VfDxrwnQPaC00cG7U/Y3Seu9Bx+X6cSEWkkMt2NkQnxkcaSOqjwBJ ecCNLsbtDXk3ShVKyISYLBvwEQ== X-Google-Smtp-Source: ACHHUZ4IHkh/4zIptqMNZ7cP5UukZG6d4pvIGvEIZbO4wZjRny0PgPxIKJeKC7pkfeGo+7IOPWJTzQ== X-Received: by 2002:a05:600c:24ce:b0:3f2:51e7:f1f4 with SMTP id 14-20020a05600c24ce00b003f251e7f1f4mr19182509wmu.10.1683923026931; Fri, 12 May 2023 13:23:46 -0700 (PDT) Received: from Mindolluin.ire.aristanetworks.com ([217.173.96.166]) by smtp.gmail.com with ESMTPSA id n9-20020a05600c294900b003f423508c6bsm17304527wmd.44.2023.05.12.13.23.45 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Fri, 12 May 2023 13:23:46 -0700 (PDT) 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 v6 20/21] net/tcp: Add static_key for TCP-AO Date: Fri, 12 May 2023 21:23:10 +0100 Message-Id: <20230512202311.2845526-21-dima@arista.com> X-Mailer: git-send-email 2.40.0 In-Reply-To: <20230512202311.2845526-1-dima@arista.com> References: <20230512202311.2845526-1-dima@arista.com> Precedence: bulk X-Mailing-List: netdev@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 X-Spam-Status: No, score=-2.1 required=5.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,DKIM_VALID_EF,RCVD_IN_DNSWL_NONE, SPF_HELO_NONE,SPF_NONE,T_SCC_BODY_TEXT_LINE,URIBL_BLOCKED autolearn=ham autolearn_force=no version=3.4.6 X-Spam-Checker-Version: SpamAssassin 3.4.6 (2021-04-09) on lindbergh.monkeyblade.net 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.h | 3 +++ include/net/tcp_ao.h | 2 ++ net/ipv4/tcp_ao.c | 23 +++++++++++++++++++++++ net/ipv4/tcp_input.c | 42 ++++++++++++++++++++++++++++-------------- 4 files changed, 56 insertions(+), 14 deletions(-) diff --git a/include/net/tcp.h b/include/net/tcp.h index e7b077805d9e..8eae8e82980f 100644 --- a/include/net/tcp.h +++ b/include/net/tcp.h @@ -2575,6 +2575,9 @@ static inline bool tcp_ao_required(struct sock *sk, const void *saddr, struct tcp_ao_info *ao_info; struct tcp_ao_key *ao_key; + if (!static_branch_unlikely(&tcp_ao_needed.key)) + return false; + ao_info = 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 d1dcda8f81be..c19c9416ff6d 100644 --- a/include/net/tcp_ao.h +++ b/include/net/tcp_ao.h @@ -138,6 +138,8 @@ 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 40b13fcb0723..3538321a742f 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_GPL(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 @@ -198,6 +204,9 @@ static 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) @@ -292,6 +301,7 @@ 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) @@ -1037,6 +1047,11 @@ 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); @@ -1443,6 +1458,10 @@ 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)) { + ret = -EUSERS; + goto err_free_sock; + } sk_gso_disable(sk); rcu_assign_pointer(tcp_sk(sk)->ao_info, ao_info); } @@ -1705,6 +1724,10 @@ 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 = -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 d87c73346e8c..7f6f9b04e9e9 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); }