From patchwork Mon Apr 3 21:34:19 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Dmitry Safonov X-Patchwork-Id: 13198828 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 D8893C77B6E for ; Mon, 3 Apr 2023 21:37:17 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S233631AbjDCVhP (ORCPT ); Mon, 3 Apr 2023 17:37:15 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:51746 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S233674AbjDCVgR (ORCPT ); Mon, 3 Apr 2023 17:36:17 -0400 Received: from mail-wr1-x42e.google.com (mail-wr1-x42e.google.com [IPv6:2a00:1450:4864:20::42e]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 97DC040FB for ; Mon, 3 Apr 2023 14:34:55 -0700 (PDT) Received: by mail-wr1-x42e.google.com with SMTP id r29so30747302wra.13 for ; Mon, 03 Apr 2023 14:34:55 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=arista.com; s=google; t=1680557695; 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=kqm9oB++B4Vusm9tIx4BlOhETDsJSBAxDzl8TFfBB/Q=; b=NHeg4cJdPCiYd4rcRrcNgDRNxweSgwCDHOc8VxnvXKftR+C2oSocpV7b5LpfpfLvCT pRems2P7Ckc1tW9AW8Zbmv2h+jK0LE0KClXcOzql2utI6Yko08QnjrcOaiE9B32Fnw81 Zp08vZmjopHLItYb/gmf+qZRGV3o/LDp0IPscBhdFAIbp93rF+7W1UE3Tnq5jifwnr2O G/CKoncDRLhDONpvTdMGFUD8OZ6bZcpkW8+CkSLedrCtnFb9GZUkMXe5XEC4hI7B0eFQ 1W8qYa6VtKS6g7N/SaImPMc57/crX+MGPGqGcl0HUTfiTlhHV4hSLsMOBYklKMUOSlM+ /hCA== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20210112; t=1680557695; 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=kqm9oB++B4Vusm9tIx4BlOhETDsJSBAxDzl8TFfBB/Q=; b=ygZlO/HOGSpD/HHvyhLcA4IJsWHSIyjjczezNSe/YITUSfPAfw/AQRbBMGIMEXSl1S Fr2nVc5yiOJqwgw5WYoafDOUlKnojzGp0uHnWW7yjxAsGhCPART4dFukVG9q49o4MOu/ bnh+x/YlGoW/2K1nbsikR41hfeDSNM42rFPO3nnuLPNroIeaky1PEHEqfo7MmHuTedjs 8FLo4li+WwMpcSfn1dDU6Gvwny9lMCBuYKu+B4aV500L/t0oi0x3I8Fk+IhAwg+5/HGk 9P+CFhmt3QmIBgrNm3mWIxZx00grEJHYDdtOoAsWq/V8uhI4dAY4BWiqiStqfPUtprqv hUew== X-Gm-Message-State: AAQBX9ePa+nLVgn9w2YrNbiEik3E32UAe0KH+Upak7y13n8cWY5pw7nq T1gOY8JpxYNhsV48gutn80yjJg== X-Google-Smtp-Source: AKy350bfYgNqm4HJWzPYLogAoyzErf2m0Vjkvblt8zXHayATBHgnNx96vQDqHiuOnwbpuMxOWDYR3A== X-Received: by 2002:a5d:464f:0:b0:2ce:a890:7371 with SMTP id j15-20020a5d464f000000b002cea8907371mr13707wrs.12.1680557695010; Mon, 03 Apr 2023 14:34:55 -0700 (PDT) Received: from Mindolluin.ire.aristanetworks.com ([217.173.96.166]) by smtp.gmail.com with ESMTPSA id o5-20020a5d4a85000000b002c3f9404c45sm10682740wrq.7.2023.04.03.14.34.53 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Mon, 03 Apr 2023 14:34:54 -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 v5 20/21] net/tcp-ao: Add static_key for TCP-AO Date: Mon, 3 Apr 2023 22:34:19 +0100 Message-Id: <20230403213420.1576559-21-dima@arista.com> X-Mailer: git-send-email 2.40.0 In-Reply-To: <20230403213420.1576559-1-dima@arista.com> References: <20230403213420.1576559-1-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.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 7b5d4ee8f6b0..4db5179d08b3 100644 --- a/include/net/tcp.h +++ b/include/net/tcp.h @@ -2574,6 +2574,9 @@ 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 d9a4b9bb9872..37adf40f6f56 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); @@ -1444,6 +1459,10 @@ 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); } @@ -1706,6 +1725,10 @@ static int tcp_ao_info_cmd(struct sock *sk, unsigned short int family, if (new_rnext) WRITE_ONCE(ao_info->current_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 d0a604b05518..622db7a6a0fb 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); }