From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from chi.subsignal.org (cxd-2-pt.tunnel.tserv11.ams1.ipv6.he.net [IPv6:2001:470:1f14:ed::2]) by huchra.bufferbloat.net (Postfix) with ESMTP id A2C6721F1A8 for ; Wed, 8 May 2013 02:48:03 -0700 (PDT) Received: from [192.168.178.21] (unknown [212.255.44.191]) by chi.subsignal.org (Postfix) with ESMTPSA id C907F126016; Wed, 8 May 2013 11:49:26 +0200 (CEST) Message-ID: <518A1F51.809@openwrt.org> Date: Wed, 08 May 2013 11:48:01 +0200 From: Steven Barth User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:17.0) Gecko/20130112 Icedove/17.0.2 MIME-Version: 1.0 To: Dave Taht Subject: Re: [homenet] Source-specific routes in Linux [was: atomic updates...] References: <87vc6vgghx.wl%jch@pps.univ-paris-diderot.fr> <8F7177E4-6212-4A74-8A7C-A2D1703A59BF@iki.fi> <87sj1zgfot.wl%jch@pps.univ-paris-diderot.fr> In-Reply-To: Content-Type: text/plain; charset=ISO-8859-1; format=flowed Content-Transfer-Encoding: 7bit X-Mailman-Approved-At: Thu, 09 May 2013 02:16:43 -0700 Cc: homenet@ietf.org, Markus Stenberg , bloat-devel , boutier@pps.univ-paris-diderot.fr, Juliusz Chroboczek X-BeenThere: bloat-devel@lists.bufferbloat.net X-Mailman-Version: 2.1.13 Precedence: list List-Id: "Developers working on AQM, device drivers, and networking stacks" List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Wed, 08 May 2013 09:48:04 -0000 On 08.05.2013 10:51, Dave Taht wrote: > One thing that bugs me about hacks and workarounds like this is that > Linux (as well as openwrt) are intensely mutable systems, and it's > totally possible to improve linux rather than limp around in userspace. > > I have long disliked the ip rule system in its primary use prior to now > (vpns), as buggy, arbitrary, and subject to race conditions, so if a > better api and methods for injecting/managing source address dependent > routing information could be designed I'm pretty sure there would be > much enthusiasm across the vpn, mptcp/sctp, and routing worlds for > getting it into linux itself. Hmm I must admit I'm wondering about this for the OpenWrt stack as well. We have switched to RA-Handling in userspace for similar reasons already so I guess it's only the next logical step to create separate routing tables for each upstream interface to do source-based routing and filter out ULA-traffic on this layer instead of through iptables. Having one central userspace management daemon for routing and address / prefix delegation in general might not be the best or cleanest solution in the end but I guess there is no better way right now.