From mboxrd@z Thu Jan 1 00:00:00 1970 From: Brian Haley Subject: Re: [PATCH] net: ipv6: Allow netlink to set IPv6 address scope Date: Mon, 17 Oct 2011 17:32:06 -0400 Message-ID: <4E9C9ED6.9080601@hp.com> References: <20111005201559.E544016A599@drone1.mtv.corp.google.com> <4E931A46.1040905@hp.com> <4E98981D.6080908@hp.com> <4E9B7A9F.7000302@hp.com> Mime-Version: 1.0 Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: 7bit Cc: maze@google.com, yoshfuji@linux-ipv6.org, netdev@vger.kernel.org To: Lorenzo Colitti Return-path: Received: from g4t0015.houston.hp.com ([15.201.24.18]:22266 "EHLO g4t0015.houston.hp.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751344Ab1JQVcJ (ORCPT ); Mon, 17 Oct 2011 17:32:09 -0400 In-Reply-To: Sender: netdev-owner@vger.kernel.org List-ID: On 10/16/2011 10:26 PM, Lorenzo Colitti wrote: > RFC 3879 deprecated site-local addresses because the were non-unique and thus > ambiguous, and if they leak, they cause problems. This is not an issue > in the use > case I presented, because the addresses are syntactically global > addresses - they > just don't have global reachability. Not very global then :( >> The MIF problem statement (in the RFC editor's queue) talks about this problem, >> http://tools.ietf.org/html/draft-ietf-mif-problem-statement-15 - perhaps it's >> better to work there to develop a more generic solution (using DHCPv6, RA >> options, etc) before making this change? > > I don't think it's a good idea. Waiting for an IETF working group to > produce a standard > when it doesn't even have a problem statement finalized could take years. It would be useful to give some input there, even if the Linux-specific implementation of any standard plays with bits in the ifaddr. > Is there another reason why we shouldn't enable userspace to do what it wants? In my opinion it just feels like a hack, because things won't work when your wifi attaches to a walled garden, or there's a third interface - who wins the tiebreaker? I do see your point that it will help with the problem you're trying to solve, hopefully someone else will offer their opinion. -Brian