From mboxrd@z Thu Jan 1 00:00:00 1970 From: Pablo Neira Ayuso Subject: Re: [PATCH netfilter] extensions/libxt_bpf.man: clarify BPF code generation with tcpdump Date: Fri, 12 Aug 2016 12:47:06 +0200 Message-ID: <20160812104706.GA3991@salvia> References: <1470856987-101558-1-git-send-email-willemdebruijn.kernel@gmail.com> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Cc: netfilter-devel@vger.kernel.org, blaffablaffa@gmail.com, Willem de Bruijn To: Willem de Bruijn Return-path: Received: from mail.us.es ([193.147.175.20]:35278 "EHLO mail.us.es" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751636AbcHLKrQ (ORCPT ); Fri, 12 Aug 2016 06:47:16 -0400 Received: from antivirus1-rhel7.int (unknown [192.168.2.11]) by mail.us.es (Postfix) with ESMTP id 604B1D1633 for ; Fri, 12 Aug 2016 12:47:13 +0200 (CEST) Received: from antivirus1-rhel7.int (localhost [127.0.0.1]) by antivirus1-rhel7.int (Postfix) with ESMTP id 5312CFF2D5 for ; Fri, 12 Aug 2016 12:47:13 +0200 (CEST) Received: from antivirus1-rhel7.int (localhost [127.0.0.1]) by antivirus1-rhel7.int (Postfix) with ESMTP id 41370FF153 for ; Fri, 12 Aug 2016 12:47:11 +0200 (CEST) Content-Disposition: inline In-Reply-To: <1470856987-101558-1-git-send-email-willemdebruijn.kernel@gmail.com> Sender: netfilter-devel-owner@vger.kernel.org List-ID: On Wed, Aug 10, 2016 at 03:23:07PM -0400, Willem de Bruijn wrote: > From: Willem de Bruijn > > The xt_bpf module applies BPF bytecode to the packet. Depending on > where the module is invoked, the kernel may pass a packet with or > without link layer header. Iptables has no such header. > > A common `tcpdump -ddd ` compilation command may revert to > a physical device that generates code for packets starting from the > mac layer up (e.g., E10MB data link type: Ethernet). > > Clarify in the man page that when using this tool for code generation, > a suitable target device must be chosen. > > Netfilter Bugzilla Bug #1048 Applied, thanks.