Re: [dbound] The proposals before us

Gervase Markham <gerv@mozilla.org> Mon, 12 September 2016 13:30 UTC

Return-Path: <gerv@mozilla.com>
X-Original-To: dbound@ietfa.amsl.com
Delivered-To: dbound@ietfa.amsl.com
Received: from localhost (localhost [127.0.0.1]) by ietfa.amsl.com (Postfix) with ESMTP id 61CDF12B295 for <dbound@ietfa.amsl.com>; Mon, 12 Sep 2016 06:30:43 -0700 (PDT)
X-Virus-Scanned: amavisd-new at amsl.com
X-Spam-Flag: NO
X-Spam-Score: -2.6
X-Spam-Level:
X-Spam-Status: No, score=-2.6 tagged_above=-999 required=5 tests=[BAYES_00=-1.9, DKIM_SIGNED=0.1, DKIM_VALID=-0.1, HEADER_FROM_DIFFERENT_DOMAINS=0.001, RCVD_IN_DNSWL_LOW=-0.7, SPF_PASS=-0.001] autolearn=ham autolearn_force=no
Authentication-Results: ietfa.amsl.com (amavisd-new); dkim=pass (2048-bit key) header.d=mozilla-org.20150623.gappssmtp.com
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 gSo2FyBZ8Gwe for <dbound@ietfa.amsl.com>; Mon, 12 Sep 2016 06:30:40 -0700 (PDT)
Received: from mail-wm0-x230.google.com (mail-wm0-x230.google.com [IPv6:2a00:1450:400c:c09::230]) (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 548DD12B2A1 for <dbound@ietf.org>; Mon, 12 Sep 2016 06:30:40 -0700 (PDT)
Received: by mail-wm0-x230.google.com with SMTP id c131so58117741wmh.0 for <dbound@ietf.org>; Mon, 12 Sep 2016 06:30:40 -0700 (PDT)
DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=mozilla-org.20150623.gappssmtp.com; s=20150623; h=subject:to:references:cc:from:message-id:date:user-agent :mime-version:in-reply-to:content-transfer-encoding; bh=3AV4oNYflCiVIyjbQyN49CmvhfDzZDI43y5piwEZf3E=; b=MS/qlts/XVPSIu6vYCmsremOo5T5gVXBmpN+8DfRHDnrUJL+vm4g4W0eEdqqV0OG5Q c7ILb2nhiEYslWuulZhAaWMdU/cs/jNV6yw5FW/+I16h2aoizcFrsLJzEFhZ8Bxthx3f zloRHfYXrR4Ea/d0bH2u2+MMAEuyXWCy6lG8aYns51uV5GfAjtuiZb+WT8f+f3oO+SiV dcWv/B5PtIAisgUmVtBSl9jIVM5M2MpFGslnT0J37uLxz/UOiOu4Klf6yBPQ90g1yNvq NvV1oCO1UB83N7kkWgaQMEtB+ImWuluqhmbUP0cayFKB8HdugMEbV8ulSSfOrVMx76x2 RmLA==
X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20130820; h=x-gm-message-state:subject:to:references:cc:from:message-id:date :user-agent:mime-version:in-reply-to:content-transfer-encoding; bh=3AV4oNYflCiVIyjbQyN49CmvhfDzZDI43y5piwEZf3E=; b=VNxY+JIq6RYelQVotxx4qklz2iIfF0jx+P7t9NEEq+wufClW0c4OeE+VdKbBOJIxo/ kYnBj/NWH9V6U/tvzNspbj0L6LwodkJg1EM9x/E31GJszedbyZwmi4mRKi620iI8EYst ft2Fp270tMDBQxrG52T/bQiNbd6uQoKAFi2f1EnA6fpwFzdKcpDRU1JMkiJKTPPXsHNv e5rgO1Pzxhahs7ucS12v+mH62/XFxMbZKl/f9jYFE+4uiUahiA8nU3rOfj860vyfXaB+ LLH4lB6FwhejIlyQThHKeR6oICFPCNXY/RTG/655Z2Fx4NgwA7NwpEkB8XIhtO+J4Gpx ly8g==
X-Gm-Message-State: AE9vXwP5G2lf3jK6AvskFEADdpCYzfyvWT3fE/V40RpJS5S0AhHCxL4cn0jonmvPwvxt5qww
X-Received: by 10.28.15.194 with SMTP id 185mr11062699wmp.58.1473687037156; Mon, 12 Sep 2016 06:30:37 -0700 (PDT)
Received: from [192.168.0.14] (cpc101302-bagu16-2-0-cust1610.1-3.cable.virginm.net. [86.21.118.75]) by smtp.gmail.com with ESMTPSA id f10sm17867428wje.14.2016.09.12.06.30.35 (version=TLS1_2 cipher=ECDHE-RSA-AES128-GCM-SHA256 bits=128/128); Mon, 12 Sep 2016 06:30:35 -0700 (PDT)
To: John R Levine <johnl@taugh.com>, Casey Deccio <casey@deccio.net>
References: <20160910211314.47140.qmail@ary.lan> <8C13CBDD-A213-47F0-8755-C1A5F0190EE9@deccio.net> <alpine.OSX.2.11.1609102313420.53927@ary.lan>
From: Gervase Markham <gerv@mozilla.org>
Message-ID: <ab8dc273-8e82-2402-97ca-0990c1fe898b@mozilla.org>
Date: Mon, 12 Sep 2016 14:30:35 +0100
User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:45.0) Gecko/20100101 Thunderbird/45.2.0
MIME-Version: 1.0
In-Reply-To: <alpine.OSX.2.11.1609102313420.53927@ary.lan>
Content-Type: text/plain; charset=utf-8
Content-Transfer-Encoding: 7bit
Archived-At: <https://mailarchive.ietf.org/arch/msg/dbound/1BVqtbF5_CDh9TlR3tyHsY_cWwI>
Cc: dbound@ietf.org
Subject: Re: [dbound] The proposals before us
X-BeenThere: dbound@ietf.org
X-Mailman-Version: 2.1.17
Precedence: list
List-Id: DNS tree bounds <dbound.ietf.org>
List-Unsubscribe: <https://www.ietf.org/mailman/options/dbound>, <mailto:dbound-request@ietf.org?subject=unsubscribe>
List-Archive: <https://mailarchive.ietf.org/arch/browse/dbound/>
List-Post: <mailto:dbound@ietf.org>
List-Help: <mailto:dbound-request@ietf.org?subject=help>
List-Subscribe: <https://www.ietf.org/mailman/listinfo/dbound>, <mailto:dbound-request@ietf.org?subject=subscribe>
X-List-Received-Date: Mon, 12 Sep 2016 13:30:43 -0000

On 11/09/16 04:44, John R Levine wrote:
> Let's say you're looking up the domain bulgaria.xn--90ae.  That's a
> name in a real TLD, and the TLD doesn't appear in the PSL.  What does
> the code do now?  Looking at some of the PSL libraries, the results
> look pretty random.  Some raise exceptions, some fall off the ends of
> routines and return null or a random result.

The PSL algorithm states that if the suffix of a given domain name is
not in the PSL, then the public suffix is the last label - so "xn--90ae"
in your example. And the PSL+1, or "registered/registrable domain" would
be bulgaria.xn--90ae.

Whether this is always correct is a matter for discussion, and whether
libraries do this is a matter for their authors, but that's what the
spec says. See "Algorithm", bullet 2:
https://publicsuffix.org/list/

Gerv