IETF Logo Mail Archive

Re: [websec] lower-casing in the idna-canonicalized host name

Adam Barth <ietf@adambarth.com> Fri, 29 July 2011 18:28 UTC

Return-Path: <ietf@adambarth.com>
X-Original-To: websec@ietfa.amsl.com
Delivered-To: websec@ietfa.amsl.com
Received: from localhost (localhost [127.0.0.1]) by ietfa.amsl.com (Postfix) with ESMTP id 363B821F8B84 for <websec@ietfa.amsl.com>; Fri, 29 Jul 2011 11:28:08 -0700 (PDT)
X-Virus-Scanned: amavisd-new at amsl.com
X-Spam-Flag: NO
X-Spam-Score: -4.219
X-Spam-Level:
X-Spam-Status: No, score=-4.219 tagged_above=-999 required=5 tests=[AWL=0.758, BAYES_00=-2.599, FM_FORGED_GMAIL=0.622, GB_I_LETTER=-2, RCVD_IN_DNSWL_LOW=-1]
Received: from mail.ietf.org ([64.170.98.30]) by localhost (ietfa.amsl.com [127.0.0.1]) (amavisd-new, port 10024) with ESMTP id zHrtCYsY9ICd for <websec@ietfa.amsl.com>; Fri, 29 Jul 2011 11:28:07 -0700 (PDT)
Received: from mail-gw0-f44.google.com (mail-gw0-f44.google.com [74.125.83.44]) by ietfa.amsl.com (Postfix) with ESMTP id A2FED21F8B82 for <websec@ietf.org>; Fri, 29 Jul 2011 11:28:07 -0700 (PDT)
Received: by gwb20 with SMTP id 20so3410916gwb.31 for <websec@ietf.org>; Fri, 29 Jul 2011 11:28:07 -0700 (PDT)
Received: by 10.236.182.225 with SMTP id o61mr754142yhm.257.1311964087228; Fri, 29 Jul 2011 11:28:07 -0700 (PDT)
Received: from mail-yi0-f44.google.com (mail-yi0-f44.google.com [209.85.218.44]) by mx.google.com with ESMTPS id j9sm518480yhn.39.2011.07.29.11.28.05 (version=SSLv3 cipher=OTHER); Fri, 29 Jul 2011 11:28:05 -0700 (PDT)
Received: by yie30 with SMTP id 30so3277814yie.31 for <websec@ietf.org>; Fri, 29 Jul 2011 11:28:05 -0700 (PDT)
Received: by 10.42.77.73 with SMTP id h9mr1175608ick.210.1311964085143; Fri, 29 Jul 2011 11:28:05 -0700 (PDT)
MIME-Version: 1.0
Received: by 10.231.190.82 with HTTP; Fri, 29 Jul 2011 11:27:35 -0700 (PDT)
In-Reply-To: <4E24B10A.1070000@lookout.net>
References: <4E248B9C.1070701@gondrom.org> <4E24B10A.1070000@lookout.net>
From: Adam Barth <ietf@adambarth.com>
Date: Fri, 29 Jul 2011 11:27:35 -0700
Message-ID: <CAJE5ia9vOshj6S+GuuCPpn66tVZ2SrVsmFD24kbWCvp2VoWAkw@mail.gmail.com>
To: Chris Weber <chris@lookout.net>
Content-Type: text/plain; charset="ISO-8859-1"
Cc: websec@ietf.org
Subject: Re: [websec] lower-casing in the idna-canonicalized host name
X-BeenThere: websec@ietf.org
X-Mailman-Version: 2.1.12
Precedence: list
List-Id: Web Application Security Minus Authentication and Transport <websec.ietf.org>
List-Unsubscribe: <https://www.ietf.org/mailman/options/websec>, <mailto:websec-request@ietf.org?subject=unsubscribe>
List-Archive: <http://www.ietf.org/mail-archive/web/websec>
List-Post: <mailto:websec@ietf.org>
List-Help: <mailto:websec-request@ietf.org?subject=help>
List-Subscribe: <https://www.ietf.org/mailman/listinfo/websec>, <mailto:websec-request@ietf.org?subject=subscribe>
X-List-Received-Date: Fri, 29 Jul 2011 18:28:08 -0000

On Mon, Jul 18, 2011 at 3:17 PM, Chris Weber <chris@lookout.net> wrote:
> Under the definition of an "idna-canonicalized" host name in section 2.3,
> step 2 - is it known that the reader will handle NR-LDH and A-labels as
> locale-insensitive ASCII, or should it be explicitly stated that the
> lower-case conversion in step "2" should be locale-insensitive, or use
> English as the locale?
>
> Otherwise even with ASCII input a lower-case operation could result in a
> U+0049 LATIN CAPITAL LETTER I becoming U+0131 LATIN SMALL LETTER DOTLESS I
> under the Turkish "tr-TR" locale.

I've added a reference to i;ascii-casemap, defined in RFC4790.
Hopefully that is unambiguous.

Thanks,
Adam

v2.23.0 | Report a Bug | By Email