From mboxrd@z Thu Jan 1 00:00:00 1970 From: Atis Elsts Subject: Re: [PATCH] Add sk_mark route lookup support for IPv4 listening sockets, and for IPv4 multicast forwarding Date: Wed, 14 Oct 2009 14:04:37 +0300 Message-ID: <200910141404.37882.atis@mikrotik.com> References: <20091007.223928.34412707.davem@davemloft.net> <55a4f86e0910140250o45532dabr33707c025dfa25f9@mail.gmail.com> <20091014092743.GA13374@fogou.chygwyn.com> Mime-Version: 1.0 Content-Type: text/plain; charset="utf-8" Content-Transfer-Encoding: 7bit Cc: Maciej =?utf-8?q?=C5=BBenczykowski?= , David Miller , netdev@vger.kernel.org, panther@balabit.hu, eric.dumazet@gmail.com, brian.haley@hp.com To: steve@chygwyn.com Return-path: Received: from bute.mt.lv ([159.148.172.196]:51430 "EHLO bute.mt.lv" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1758569AbZJNLE0 (ORCPT ); Wed, 14 Oct 2009 07:04:26 -0400 In-Reply-To: <20091014092743.GA13374@fogou.chygwyn.com> Content-Disposition: inline Sender: netdev-owner@vger.kernel.org List-ID: On Wednesday 14 October 2009 12:27:43 steve@chygwyn.com wrote: > > The mark is supposed to be a generic thing, not just for routing > lookups, it can be used for classification, etc as well. In general, sounds like a good idea, but IMHO exactly this could be a problem. skb->mark is already used for a lot of things. What if I am setting the mark by a firewall rule in prerouting chain, and matching it by a postrouting rule? If routing lookup was changing the mark, then my setup would break. Perhaps one more field could be added dst_entry? The field would be filled from route's table (if "setmark" for that route was specified). The use of that field would be similar to tclassid (e.g matching in firewall), except that it would also be used in routing lookups, if set. > I would > expect to see such a thing used for maybe specifying a VLAN or > a reference to an MPLS label stack, or something similar too, > > Steve.