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: 339841 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-16.7 required=3.0 tests=BAYES_00, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER,INCLUDES_PATCH, MAILING_LIST_MULTI, SPF_HELO_NONE, SPF_PASS, URIBL_BLOCKED, USER_AGENT_GIT autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 7FAEEC4361B for ; Mon, 7 Dec 2020 13:43:59 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 4410F208DB for ; Mon, 7 Dec 2020 13:43:59 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726096AbgLGNn4 (ORCPT ); Mon, 7 Dec 2020 08:43:56 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:32950 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726067AbgLGNnz (ORCPT ); Mon, 7 Dec 2020 08:43:55 -0500 Received: from orbyte.nwl.cc (orbyte.nwl.cc [IPv6:2001:41d0:e:133a::1]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 82359C0613D1; Mon, 7 Dec 2020 05:43:15 -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: linux-crypto@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);