Re: [v6ops] prefix length ban for RFC4861 (Re: A proposal for draft-ietf-6man-rfc4291bis-07)

Timothy Winters <twinters@iol.unh.edu> Mon, 06 March 2017 23:45 UTC

Return-Path: <twinters@iol.unh.edu>
X-Original-To: ipv6@ietfa.amsl.com
Delivered-To: ipv6@ietfa.amsl.com
Received: from localhost (localhost [127.0.0.1]) by ietfa.amsl.com (Postfix) with ESMTP id D0FB51294AE for <ipv6@ietfa.amsl.com>; Mon, 6 Mar 2017 15:45:12 -0800 (PST)
X-Virus-Scanned: amavisd-new at amsl.com
X-Spam-Flag: NO
X-Spam-Score: -2.7
X-Spam-Level:
X-Spam-Status: No, score=-2.7 tagged_above=-999 required=5 tests=[BAYES_00=-1.9, DKIM_SIGNED=0.1, DKIM_VALID=-0.1, DKIM_VALID_AU=-0.1, HTML_MESSAGE=0.001, RCVD_IN_DNSWL_LOW=-0.7, SPF_PASS=-0.001] autolearn=unavailable autolearn_force=no
Authentication-Results: ietfa.amsl.com (amavisd-new); dkim=pass (1024-bit key) header.d=iol.unh.edu
Received: from mail.ietf.org ([4.31.198.44]) by localhost (ietfa.amsl.com [127.0.0.1]) (amavisd-new, port 10024) with ESMTP id OrSRI05m7c2s for <ipv6@ietfa.amsl.com>; Mon, 6 Mar 2017 15:45:10 -0800 (PST)
Received: from mail-qk0-x232.google.com (mail-qk0-x232.google.com [IPv6:2607:f8b0:400d:c09::232]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by ietfa.amsl.com (Postfix) with ESMTPS id 0D673129876 for <ipv6@ietf.org>; Mon, 6 Mar 2017 15:45:10 -0800 (PST)
Received: by mail-qk0-x232.google.com with SMTP id 1so181774302qkl.3 for <ipv6@ietf.org>; Mon, 06 Mar 2017 15:45:10 -0800 (PST)
DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=iol.unh.edu; s=unh-iol; h=mime-version:in-reply-to:references:from:date:message-id:subject:to :cc; bh=NPEBCO0vyUvZ2jXl+Tt1JJUNUf5TFBIOodWjXYikxmM=; b=dRmFawg9VAUpbBefV5itdjanF6RVj4POcuVlV2tXunZeljErp3Do03JhWv9i7IKJSn 3HUlddZ9T/pb6R5mCFmG4PI5hyWOcqqYd8lFCMiyTM84BpWCw1KYtgKkFc6uZCcOP9I7 /juB20BaOCVwFvdj/fgdWRRBcwqVSttOFsdlA=
X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:mime-version:in-reply-to:references:from:date :message-id:subject:to:cc; bh=NPEBCO0vyUvZ2jXl+Tt1JJUNUf5TFBIOodWjXYikxmM=; b=J9XIneKmSdyJmIViRAFdx8bcvsroMCA5+uPAW+RzUiThr6T4mXswf/IuwOTBu/jvke Ad7kMzK7YiB6vkDEt6pR6u7vtx5SbVCYFNarwlu7P3a2RfxWuOtt8NYmo8RTioFCZhBW JsbnQl/miS7VjB4unWS4v46dinXf7bl0IohPbWvn2rGvEKliCTDTS9gwOgNPEBS8+rUe XUBb4dDTaTX/sedV4s6+WHulvLfEm+uUtRwE85l6fM5d1qzofmLxWluSpnnwEnIJF1PP fC8auFNRwUnra9cvBhSr+PK/UaqxYgHlf2tAazysTBLh0ZH8uriZoUZApH9NxtJ3pB4D OC6w==
X-Gm-Message-State: AMke39newxGQy0SBuLu1wYw1RH3kVHRKcWHJylk4hVJFl5lGAQixoy56l4FLJkSYEbc6aFlt3bC8hEkMTSgu3m17
X-Received: by 10.237.36.172 with SMTP id t41mr17647032qtc.142.1488843909134; Mon, 06 Mar 2017 15:45:09 -0800 (PST)
MIME-Version: 1.0
Received: by 10.200.37.225 with HTTP; Mon, 6 Mar 2017 15:45:08 -0800 (PST)
In-Reply-To: <7F00A187-28E5-4D6E-8F24-771EC80AC078@google.com>
References: <CAJE_bqc2JUcZZsuZtW9EzdA3Swu78JMFF3_QheXZqocgzoj43w@mail.gmail.com> <7F00A187-28E5-4D6E-8F24-771EC80AC078@google.com>
From: Timothy Winters <twinters@iol.unh.edu>
Date: Mon, 6 Mar 2017 18:45:08 -0500
Message-ID: <CAOSSMjWEpDmhCU-7w69QMZxqxhFL61gq8RzTbxdf00H1Vm7v0A@mail.gmail.com>
Subject: Re: [v6ops] prefix length ban for RFC4861 (Re: A proposal for draft-ietf-6man-rfc4291bis-07)
To: james woodyatt <jhw@google.com>
Content-Type: multipart/alternative; boundary=001a113f386454b63e054a187c57
Archived-At: <https://mailarchive.ietf.org/arch/msg/ipv6/Y2MTr0waiwSPFhKpCIYF-_0WdY8>
Cc: IPv6 Operations <v6ops@ietf.org>, 6man WG <ipv6@ietf.org>, =?UTF-8?B?56We5piO6YGU5ZOJ?= <jinmei@wide.ad.jp>
X-BeenThere: ipv6@ietf.org
X-Mailman-Version: 2.1.17
Precedence: list
List-Id: "IPv6 Maintenance Working Group \(6man\)" <ipv6.ietf.org>
List-Unsubscribe: <https://www.ietf.org/mailman/options/ipv6>, <mailto:ipv6-request@ietf.org?subject=unsubscribe>
List-Archive: <https://mailarchive.ietf.org/arch/browse/ipv6/>
List-Post: <mailto:ipv6@ietf.org>
List-Help: <mailto:ipv6-request@ietf.org?subject=help>
List-Subscribe: <https://www.ietf.org/mailman/listinfo/ipv6>, <mailto:ipv6-request@ietf.org?subject=subscribe>
X-List-Received-Date: Mon, 06 Mar 2017 23:45:13 -0000

The USGv6 and IPv6 Ready Logo have the same test for the PIO option with a
prefix length larger then 64.

It's test 2.2.19 in the IPv6 Core Test Specification
<https://www.ipv6ready.org/docs/Core_Conformance_Latest.pdf>;.

It checks that a device is capable of determining the on-link prefix with a
length set to 96.   All IPv6 Ready Logo/USGv6 Basic devices support this
properly.

~Tim

On Mon, Mar 6, 2017 at 5:26 PM, james woodyatt <jhw@google.com>; wrote:

> On Mar 6, 2017, at 14:15, 神明達哉 <jinmei@wide.ad.jp>; wrote:
>
>
> BSD variants did NOT ignore PIO for on-link determination simply due
> to its prefix length value at least at the time of the publication of
> RFC4862 (actually since way before that RFC).  For example, this is
> FreeBSD's implementation as of Oct 21, 2005, about two years before
> RFC4862 was published:
> https://github.com/freebsd/freebsd/blob/c2b19f24a4ba01108e047a35a4a060
> cbfdf28a17/sys/netinet6/nd6_rtr.c
> see nd6_prelist_add() starting at line 993, and find that it only
> checks the prefix length for SLAAC (lines from 1258).  At this point
> the on-link determination has been completed without any check on the
> prefix length (lines 1043-1056).
>
>
> Indeed, I am unable to find source code history in FreeBSD, NetBSD or
> Darwin consistent with my memory. Perhaps I am mistaken that it was ever
> there.
>
> order to pass a certification test. I believe these implementations
> will not any longer pass that test. (One imagines either their
> owners don’t care, or the test has been revised to be more lenient.)
>
>
> This is quite surprising to me.  Do you have any reference to such a
> certification test that requires the host to ignore PIO with a non-64
> prefix length for the purpose of on-link determination (i.e., for
> RFC4861)?
>
>
> My admittedly questionable memory is that it was a USGv6 Test Program for
> SLAAC [Host] Conformance that checked for this behavior in a host
> implementation I maintained at the time. As I said, I wouldn’t be surprised
> if that test has been revised to be more lenient, but I remember having to
> modify the KAME source code to pass the test.
>
> Nevertheless, the LwIP stack does what I’m talking about, and it’s used in
> a plethora of constrained resource host operating systems these days.
>
>
> --james woodyatt <jhw@google.com>;
>
>
>
>
> --------------------------------------------------------------------
> IETF IPv6 working group mailing list
> ipv6@ietf.org
> Administrative Requests: https://www.ietf.org/mailman/listinfo/ipv6
> --------------------------------------------------------------------
>
>


-- 

Now offering testing for SDN applications and controllers in our SDN switch
test bed. Learn more today http://bit.ly/SDN_IOLPR