IETF Logo Mail Archive

Re: [TLS] draft-ietf-tls-curve25519-01: Is public key validation necessary or helpful?

Viktor Dukhovni <ietf-dane@dukhovni.org> Wed, 23 December 2015 01:13 UTC

Return-Path: <ietf-dane@dukhovni.org>
X-Original-To: tls@ietfa.amsl.com
Delivered-To: tls@ietfa.amsl.com
Received: from localhost (ietfa.amsl.com [127.0.0.1]) by ietfa.amsl.com (Postfix) with ESMTP id 4C47A1ACE30 for <tls@ietfa.amsl.com>; Tue, 22 Dec 2015 17:13:06 -0800 (PST)
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, RCVD_IN_DNSWL_LOW=-0.7] autolearn=ham
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 7_V6oezJpsKj for <tls@ietfa.amsl.com>; Tue, 22 Dec 2015 17:13:05 -0800 (PST)
Received: from mournblade.imrryr.org (mournblade.imrryr.org [38.117.134.19]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by ietfa.amsl.com (Postfix) with ESMTPS id ED7941AC40B for <tls@ietf.org>; Tue, 22 Dec 2015 17:13:04 -0800 (PST)
Received: by mournblade.imrryr.org (Postfix, from userid 1034) id 07F45284AED; Wed, 23 Dec 2015 01:13:04 +0000 (UTC)
Date: Wed, 23 Dec 2015 01:13:03 +0000
From: Viktor Dukhovni <ietf-dane@dukhovni.org>
To: tls@ietf.org
Message-ID: <20151223011303.GP18704@mournblade.imrryr.org>
References: <CAFewVt4Midtq7X6px4=A4hGkspQuJdzZQ907U=SJox0SdgfAJg@mail.gmail.com> <CACsn0cng1o-5hm=zuL6puOGJ8A2bjB=fFsaFsBCmmVofNSuumg@mail.gmail.com> <CABkgnnXQS3Ek6jDjx0aSQmaf+=EjfGWa8MG1AO4QwhJbK50VQg@mail.gmail.com> <CAFewVt4NSGDP_At8XsX4OsxSUaj_2kRyFP_keDQhfnR0=mBhrg@mail.gmail.com> <CABkgnnUq0_28U6VqE=ZPpwutOBUkTGwhxqHQOEvQve5JYfSVRA@mail.gmail.com> <CAFewVt6fyqbOZfQkWY=9SM20WcrP0UhfH+3wvXjiYoTjPm2pgA@mail.gmail.com>
MIME-Version: 1.0
Content-Type: text/plain; charset=us-ascii
Content-Disposition: inline
In-Reply-To: <CAFewVt6fyqbOZfQkWY=9SM20WcrP0UhfH+3wvXjiYoTjPm2pgA@mail.gmail.com>
User-Agent: Mutt/1.5.24 (2015-08-30)
Archived-At: <http://mailarchive.ietf.org/arch/msg/tls/so2HpHsCAOHo-DwbX6f19JnfxE0>
Subject: Re: [TLS] draft-ietf-tls-curve25519-01: Is public key validation necessary or helpful?
X-BeenThere: tls@ietf.org
X-Mailman-Version: 2.1.15
Precedence: list
Reply-To: tls@ietf.org
List-Id: "This is the mailing list for the Transport Layer Security working group of the IETF." <tls.ietf.org>
List-Unsubscribe: <https://www.ietf.org/mailman/options/tls>, <mailto:tls-request@ietf.org?subject=unsubscribe>
List-Archive: <https://mailarchive.ietf.org/arch/browse/tls/>
List-Post: <mailto:tls@ietf.org>
List-Help: <mailto:tls-request@ietf.org?subject=help>
List-Subscribe: <https://www.ietf.org/mailman/listinfo/tls>, <mailto:tls-request@ietf.org?subject=subscribe>
X-List-Received-Date: Wed, 23 Dec 2015 01:13:06 -0000

On Tue, Dec 22, 2015 at 02:09:32PM -1000, Brian Smith wrote:

> If checking that the shared value isn't zero is sufficient

It should suffice, ideally with a constant-time comparison.

-- 
	Viktor.

v2.1.27 | Report a Bug | By Email