From patchwork Mon Dec 7 13:43:09 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Phil Sutter X-Patchwork-Id: 1412049 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=none (p=none dis=none) header.from=nwl.cc Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by ozlabs.org (Postfix) with ESMTP id 4CqQ4L4MJgz9sWY for ; Tue, 8 Dec 2020 01:02:42 +1100 (AEDT) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726423AbgLGOCd (ORCPT ); Mon, 7 Dec 2020 09:02:33 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:35860 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1725822AbgLGOCd (ORCPT ); Mon, 7 Dec 2020 09:02:33 -0500 X-Greylist: delayed 1117 seconds by postgrey-1.37 at lindbergh.monkeyblade.net; Mon, 07 Dec 2020 06:01:52 PST Received: from orbyte.nwl.cc (orbyte.nwl.cc [IPv6:2001:41d0:e:133a::1]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 9E4F6C0613D0 for ; Mon, 7 Dec 2020 06:01:52 -0800 (PST) Received: from localhost ([::1]:60640 helo=tatos) by orbyte.nwl.cc with esmtp (Exim 4.94) (envelope-from ) id 1kmGnJ-0000vd-Cb; Mon, 07 Dec 2020 14:43:13 +0100 From: Phil Sutter To: Steffen Klassert Cc: linux-crypto@vger.kernel.org, netfilter-devel@vger.kernel.org, netdev@vger.kernel.org, Nicolas Dichtel Subject: [PATCH v2] xfrm: interface: Don't hide plain packets from netfilter Date: Mon, 7 Dec 2020 14:43:09 +0100 Message-Id: <20201207134309.16762-1-phil@nwl.cc> X-Mailer: git-send-email 2.28.0 MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: netdev@vger.kernel.org With an IPsec tunnel without dedicated interface, netfilter sees locally generated packets twice as they exit the physical interface: Once as "the inner packet" with IPsec context attached and once as the encrypted (ESP) packet. With xfrm_interface, the inner packet did not traverse NF_INET_LOCAL_OUT hook anymore, making it impossible to match on both inner header values and associated IPsec data from that hook. Fix this by looping packets transmitted from xfrm_interface through NF_INET_LOCAL_OUT before passing them on to dst_output(), which makes behaviour consistent again from netfilter's point of view. Fixes: f203b76d78092 ("xfrm: Add virtual xfrm interfaces") Signed-off-by: Phil Sutter --- Changes since v1: - Extend recipients list, no code changes. --- net/xfrm/xfrm_interface.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) diff --git a/net/xfrm/xfrm_interface.c b/net/xfrm/xfrm_interface.c index aa4cdcf69d471..24af61c95b4d4 100644 --- a/net/xfrm/xfrm_interface.c +++ b/net/xfrm/xfrm_interface.c @@ -317,7 +317,8 @@ xfrmi_xmit2(struct sk_buff *skb, struct net_device *dev, struct flowi *fl) skb_dst_set(skb, dst); skb->dev = tdev; - err = dst_output(xi->net, skb->sk, skb); + err = NF_HOOK(skb_dst(skb)->ops->family, NF_INET_LOCAL_OUT, xi->net, + skb->sk, skb, NULL, skb_dst(skb)->dev, dst_output); if (net_xmit_eval(err) == 0) { struct pcpu_sw_netstats *tstats = this_cpu_ptr(dev->tstats);