From patchwork Fri Jul 17 10:35:31 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Jakub Sitnicki X-Patchwork-Id: 1331042 X-Patchwork-Delegate: bpf@iogearbox.net Return-Path: X-Original-To: patchwork-incoming-netdev@ozlabs.org Delivered-To: patchwork-incoming-netdev@ozlabs.org Authentication-Results: ozlabs.org; spf=pass (sender SPF authorized) smtp.mailfrom=vger.kernel.org (client-ip=23.128.96.18; helo=vger.kernel.org; envelope-from=netdev-owner@vger.kernel.org; receiver=) Authentication-Results: ozlabs.org; dmarc=pass (p=reject dis=none) header.from=cloudflare.com Authentication-Results: ozlabs.org; dkim=pass (1024-bit key; secure) header.d=cloudflare.com header.i=@cloudflare.com header.a=rsa-sha256 header.s=google header.b=mWIffWZd; dkim-atps=neutral Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by ozlabs.org (Postfix) with ESMTP id 4B7SG86GS4z9sRW for ; Fri, 17 Jul 2020 20:36:16 +1000 (AEST) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726777AbgGQKgB (ORCPT ); Fri, 17 Jul 2020 06:36:01 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:36184 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726619AbgGQKf4 (ORCPT ); Fri, 17 Jul 2020 06:35:56 -0400 Received: from mail-lj1-x241.google.com (mail-lj1-x241.google.com [IPv6:2a00:1450:4864:20::241]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 8E02CC08C5E0 for ; Fri, 17 Jul 2020 03:35:55 -0700 (PDT) Received: by mail-lj1-x241.google.com with SMTP id j11so12020582ljo.7 for ; Fri, 17 Jul 2020 03:35:55 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=cloudflare.com; s=google; h=from:to:cc:subject:date:message-id:in-reply-to:references :mime-version:content-transfer-encoding; bh=zxJH2GAZm69sAYbUnzoD13o3dlmlVhw7Uh36sUPZfy8=; b=mWIffWZdY3rDJXD5U2n31gQ+qRbzhu6fe2jRdKO7Y/TZYd4k/giZFs4YwbE1NHbX0q qOdmUJGHrWuWP/MmBjxc5Ca+NayyIVQzVNURE2Uj9TN0dtIydKqWpjuDd/S/5ObKQrey pQN3vCMZ8yh46yD8GpkxcCQOuL/YBmAWf+9Fg= X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:from:to:cc:subject:date:message-id:in-reply-to :references:mime-version:content-transfer-encoding; bh=zxJH2GAZm69sAYbUnzoD13o3dlmlVhw7Uh36sUPZfy8=; b=p42A3dltv/gt8OKAVm+rl3wd+UK/yIQxLEsQ78nWbjWwqpnL2A6KP3Pq3hBr2+54Tl QR3lx3yywaDnUsyDaJkq8blPPN00CyrVxss8jvE2hWMRgpi4vEQ2t0XV4w2SuBjxFSUR pn8XtyIBigdZETjQra/0n/++ad15t4l6pwOOuAsc3CL+GELCcSvG7IFwZ6AkQjOLaFX7 vwlTwX0AvzL+1MxxIalEn9zd0pbSOkOkQqCrLjvG29USDRap3+05rVLjCxUoaeRR65fr SU6TAqhucTEsN34EDakHMpdfIQj4o89Kj07h+af3rlTp2zMOCbBOw7nj5UuVMLBACx81 7c+A== X-Gm-Message-State: AOAM532vxZrUNbbSLK7Pv+gBe13fawQx6z9MZWCL52fP4xS9BxiikYiW cQzO7XPBZHDsDS4seQKItoC+Cw== X-Google-Smtp-Source: ABdhPJz9Jc4U038Fwk/ocHCuTF43yxRkz6GCrztUblGnTr55PP2OzFeC3XX5sAPu6DW9N9ugIbGb5Q== X-Received: by 2002:a2e:8804:: with SMTP id x4mr4249671ljh.56.1594982154041; Fri, 17 Jul 2020 03:35:54 -0700 (PDT) Received: from cloudflare.com ([2a02:a310:c262:aa00:b35e:8938:2c2a:ba8b]) by smtp.gmail.com with ESMTPSA id s7sm1574657ljc.86.2020.07.17.03.35.53 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Fri, 17 Jul 2020 03:35:53 -0700 (PDT) From: Jakub Sitnicki To: bpf@vger.kernel.org Cc: netdev@vger.kernel.org, kernel-team@cloudflare.com, Alexei Starovoitov , Daniel Borkmann , "David S. Miller" , Jakub Kicinski , Marek Majkowski , Andrii Nakryiko Subject: [PATCH bpf-next v5 10/15] udp6: Run SK_LOOKUP BPF program on socket lookup Date: Fri, 17 Jul 2020 12:35:31 +0200 Message-Id: <20200717103536.397595-11-jakub@cloudflare.com> X-Mailer: git-send-email 2.25.4 In-Reply-To: <20200717103536.397595-1-jakub@cloudflare.com> References: <20200717103536.397595-1-jakub@cloudflare.com> MIME-Version: 1.0 Sender: netdev-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: netdev@vger.kernel.org Same as for udp4, let BPF program override the socket lookup result, by selecting a receiving socket of its choice or failing the lookup, if no connected UDP socket matched packet 4-tuple. Suggested-by: Marek Majkowski Acked-by: Andrii Nakryiko Signed-off-by: Jakub Sitnicki --- Notes: v4: - Adapt to change in bpf_sk_lookup_run_v6 return value semantics. v3: - Use a static_key to minimize the hook overhead when not used. (Alexei) - Adapt for running an array of attached programs. (Alexei) - Adapt for optionally skipping reuseport selection. (Martin) net/ipv6/udp.c | 60 ++++++++++++++++++++++++++++++++++++++++++-------- 1 file changed, 51 insertions(+), 9 deletions(-) diff --git a/net/ipv6/udp.c b/net/ipv6/udp.c index 084205c18a33..ff8be202726a 100644 --- a/net/ipv6/udp.c +++ b/net/ipv6/udp.c @@ -190,6 +190,31 @@ static struct sock *udp6_lib_lookup2(struct net *net, return result; } +static inline struct sock *udp6_lookup_run_bpf(struct net *net, + struct udp_table *udptable, + struct sk_buff *skb, + const struct in6_addr *saddr, + __be16 sport, + const struct in6_addr *daddr, + u16 hnum) +{ + struct sock *sk, *reuse_sk; + bool no_reuseport; + + if (udptable != &udp_table) + return NULL; /* only UDP is supported */ + + no_reuseport = bpf_sk_lookup_run_v6(net, IPPROTO_UDP, + saddr, sport, daddr, hnum, &sk); + if (no_reuseport || IS_ERR_OR_NULL(sk)) + return sk; + + reuse_sk = lookup_reuseport(net, sk, skb, saddr, sport, daddr, hnum); + if (reuse_sk) + sk = reuse_sk; + return sk; +} + /* rcu_read_lock() must be held */ struct sock *__udp6_lib_lookup(struct net *net, const struct in6_addr *saddr, __be16 sport, @@ -200,25 +225,42 @@ struct sock *__udp6_lib_lookup(struct net *net, unsigned short hnum = ntohs(dport); unsigned int hash2, slot2; struct udp_hslot *hslot2; - struct sock *result; + struct sock *result, *sk; hash2 = ipv6_portaddr_hash(net, daddr, hnum); slot2 = hash2 & udptable->mask; hslot2 = &udptable->hash2[slot2]; + /* Lookup connected or non-wildcard sockets */ result = udp6_lib_lookup2(net, saddr, sport, daddr, hnum, dif, sdif, hslot2, skb); - if (!result) { - hash2 = ipv6_portaddr_hash(net, &in6addr_any, hnum); - slot2 = hash2 & udptable->mask; + if (!IS_ERR_OR_NULL(result) && result->sk_state == TCP_ESTABLISHED) + goto done; + + /* Lookup redirect from BPF */ + if (static_branch_unlikely(&bpf_sk_lookup_enabled)) { + sk = udp6_lookup_run_bpf(net, udptable, skb, + saddr, sport, daddr, hnum); + if (sk) { + result = sk; + goto done; + } + } - hslot2 = &udptable->hash2[slot2]; + /* Got non-wildcard socket or error on first lookup */ + if (result) + goto done; - result = udp6_lib_lookup2(net, saddr, sport, - &in6addr_any, hnum, dif, sdif, - hslot2, skb); - } + /* Lookup wildcard sockets */ + hash2 = ipv6_portaddr_hash(net, &in6addr_any, hnum); + slot2 = hash2 & udptable->mask; + hslot2 = &udptable->hash2[slot2]; + + result = udp6_lib_lookup2(net, saddr, sport, + &in6addr_any, hnum, dif, sdif, + hslot2, skb); +done: if (IS_ERR(result)) return NULL; return result;