From mboxrd@z Thu Jan 1 00:00:00 1970 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 mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 646F3C433EF for ; Sun, 17 Oct 2021 22:15:49 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 4E0C1610E8 for ; Sun, 17 Oct 2021 22:15:49 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1344773AbhJQWR4 (ORCPT ); Sun, 17 Oct 2021 18:17:56 -0400 Received: from mail.netfilter.org ([217.70.188.207]:53416 "EHLO mail.netfilter.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1344762AbhJQWRy (ORCPT ); Sun, 17 Oct 2021 18:17:54 -0400 Received: from localhost.localdomain (unknown [78.30.32.163]) by mail.netfilter.org (Postfix) with ESMTPSA id D4A3063F10; Mon, 18 Oct 2021 00:14:02 +0200 (CEST) From: Pablo Neira Ayuso To: netfilter-devel@vger.kernel.org Cc: davem@davemloft.net, netdev@vger.kernel.org, kuba@kernel.org Subject: [PATCH nf-next 06/15] af_packet: Introduce egress hook Date: Mon, 18 Oct 2021 00:15:13 +0200 Message-Id: <20211017221522.853838-7-pablo@netfilter.org> X-Mailer: git-send-email 2.30.2 In-Reply-To: <20211017221522.853838-1-pablo@netfilter.org> References: <20211017221522.853838-1-pablo@netfilter.org> MIME-Version: 1.0 Content-Transfer-Encoding: 8bit Precedence: bulk List-ID: X-Mailing-List: netfilter-devel@vger.kernel.org Add egress hook for AF_PACKET sockets that have the PACKET_QDISC_BYPASS socket option set to on, which allows packets to escape without being filtered in the egress path. This patch only updates the AF_PACKET path, it does not update dev_direct_xmit() so the XDP infrastructure has a chance to bypass Netfilter. [lukas: acquire rcu_read_lock, fix typos, rebase] Signed-off-by: Lukas Wunner Signed-off-by: Pablo Neira Ayuso --- net/packet/af_packet.c | 35 +++++++++++++++++++++++++++++++++++ 1 file changed, 35 insertions(+) diff --git a/net/packet/af_packet.c b/net/packet/af_packet.c index 2a2bc64f75cf..46943a18a10d 100644 --- a/net/packet/af_packet.c +++ b/net/packet/af_packet.c @@ -91,6 +91,7 @@ #endif #include #include +#include #include "internal.h" @@ -241,8 +242,42 @@ struct packet_skb_cb { static void __fanout_unlink(struct sock *sk, struct packet_sock *po); static void __fanout_link(struct sock *sk, struct packet_sock *po); +#ifdef CONFIG_NETFILTER_EGRESS +static noinline struct sk_buff *nf_hook_direct_egress(struct sk_buff *skb) +{ + struct sk_buff *next, *head = NULL, *tail; + int rc; + + rcu_read_lock(); + for (; skb != NULL; skb = next) { + next = skb->next; + skb_mark_not_on_list(skb); + + if (!nf_hook_egress(skb, &rc, skb->dev)) + continue; + + if (!head) + head = skb; + else + tail->next = skb; + + tail = skb; + } + rcu_read_unlock(); + + return head; +} +#endif + static int packet_direct_xmit(struct sk_buff *skb) { +#ifdef CONFIG_NETFILTER_EGRESS + if (nf_hook_egress_active()) { + skb = nf_hook_direct_egress(skb); + if (!skb) + return NET_XMIT_DROP; + } +#endif return dev_direct_xmit(skb, packet_pick_tx_queue(skb)); } -- 2.30.2