Re: [Cfrg] (flaws with Curve25519 DH function, if one does not check the output) Re: Elliptic Curves - curve form and coordinate systems
David Leon Gil <coruus@gmail.com> Mon, 16 March 2015 22:08 UTC
Return-Path: <coruus@gmail.com>
X-Original-To: cfrg@ietfa.amsl.com
Delivered-To: cfrg@ietfa.amsl.com
Received: from localhost (ietfa.amsl.com [127.0.0.1]) by ietfa.amsl.com (Postfix) with ESMTP id 349741A1BA9 for <cfrg@ietfa.amsl.com>; Mon, 16 Mar 2015 15:08:40 -0700 (PDT)
X-Virus-Scanned: amavisd-new at amsl.com
X-Spam-Flag: NO
X-Spam-Score: -0.999
X-Spam-Level:
X-Spam-Status: No, score=-0.999 tagged_above=-999 required=5 tests=[BAYES_00=-1.9, DKIM_SIGNED=0.1, DKIM_VALID=-0.1, DKIM_VALID_AU=-0.1, FREEMAIL_FROM=0.001, FREEMAIL_REPLY=1, HTML_MESSAGE=0.001, SPF_PASS=-0.001] autolearn=no
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 FEGfJMhtGee7 for <cfrg@ietfa.amsl.com>; Mon, 16 Mar 2015 15:08:39 -0700 (PDT)
Received: from mail-yh0-x22c.google.com (mail-yh0-x22c.google.com [IPv6:2607:f8b0:4002:c01::22c]) (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 444831A1BA7 for <cfrg@irtf.org>; Mon, 16 Mar 2015 15:08:39 -0700 (PDT)
Received: by yhpt93 with SMTP id t93so22390731yhp.0 for <cfrg@irtf.org>; Mon, 16 Mar 2015 15:08:38 -0700 (PDT)
DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20120113; h=mime-version:in-reply-to:references:date:message-id:subject:from:to :cc:content-type; bh=/7NnPV24lvQ8WbAqHGFgCPdmQ8ytG5Bwyb9jcWnAwTI=; b=iuloW3aQ+V7ej6yzrg+FAx75KrirXNMbpZyguXYOpW9Q+TGMnfo7+jJxPNMxFsuqBl wpNELQx0t6LyJNmnWGIUXgw6c0a3JXC9ytBD3fz2vpin/lhMfB3vZ8/dZkWxJri2w2bC P091ubisH8iX/12hvUipwtlXVc/T6EwxtkXhFhTh36soAQiczwVjGTQulLSepLZyryPh SeTPZq+MjLnNZFmCuKgNLpPWkq9yXuh3mBhecXw5p54e9GiS33IUBsxSkTF3KITLcROY jYkdq538xLjpwNpOxTJqM6cN30SK40eKLL12SguVmig+R3KKR8WjXmC1N/DcjU/ussyI 88Dg==
MIME-Version: 1.0
X-Received: by 10.236.26.138 with SMTP id c10mr65041714yha.36.1426543718756; Mon, 16 Mar 2015 15:08:38 -0700 (PDT)
Received: by 10.170.125.80 with HTTP; Mon, 16 Mar 2015 15:08:38 -0700 (PDT)
In-Reply-To: <CACsn0ck6EY1PVB39a6gTxrnxgPTY_quMRGya2jm79CsH4iLC4Q@mail.gmail.com>
References: <5501E6A5.5040608@brainhub.org> <A6F30412-8E0A-4D8D-9F26-580307B46874@shiftleft.org> <20150316002255.28855.qmail@cr.yp.to> <20150316044906.GA27479@mournblade.imrryr.org> <5506D5BB.3090700@gmail.com> <20150316135620.GC27479@mournblade.imrryr.org> <5506EF80.7010809@gmail.com> <CACsn0ck6EY1PVB39a6gTxrnxgPTY_quMRGya2jm79CsH4iLC4Q@mail.gmail.com>
Date: Mon, 16 Mar 2015 15:08:38 -0700
Message-ID: <CAA7UWsW-NGZ7PEn1iLF9r_rOxuJsntCiKVJjm56JG4yhc4U0PA@mail.gmail.com>
From: David Leon Gil <coruus@gmail.com>
To: Watson Ladd <watsonbladd@gmail.com>
Content-Type: multipart/alternative; boundary="047d7b673c769cf61105116f1761"
Archived-At: <http://mailarchive.ietf.org/arch/msg/cfrg/8HWAFqDgs9s3ZtoqhGFuzG_49HU>
Cc: "cfrg@irtf.org" <cfrg@irtf.org>
Subject: Re: [Cfrg] (flaws with Curve25519 DH function, if one does not check the output) Re: Elliptic Curves - curve form and coordinate systems
X-BeenThere: cfrg@irtf.org
X-Mailman-Version: 2.1.15
Precedence: list
List-Id: Crypto Forum Research Group <cfrg.irtf.org>
List-Unsubscribe: <http://www.irtf.org/mailman/options/cfrg>, <mailto:cfrg-request@irtf.org?subject=unsubscribe>
List-Archive: <http://www.irtf.org/mail-archive/web/cfrg/>
List-Post: <mailto:cfrg@irtf.org>
List-Help: <mailto:cfrg-request@irtf.org?subject=help>
List-Subscribe: <http://www.irtf.org/mailman/listinfo/cfrg>, <mailto:cfrg-request@irtf.org?subject=subscribe>
X-List-Received-Date: Mon, 16 Mar 2015 22:08:40 -0000
On Monday, March 16, 2015, Watson Ladd <watsonbladd@gmail.com> wrote: > On Mon, Mar 16, 2015 at 7:58 AM, Rene Struik <rstruik.ext@gmail.com > <javascript:;>> wrote: > > But let's assume that we need contributory behavior. Then simply > returning an ignorable error code doesn't work. Instead the function > should return 32 random bytes if computing 0, so as to avoid ignoring > the errors. > I'm really inclined to think that it is better to use an encoding format that rejects points that do not ensure contributory behavior. I don't think that it's wise to assume that protocol designers will understand when this is required as well as you do. (Indeed, I'm unaware of any Curve25519 implementation that checks for this at present...)
- Re: [Cfrg] Elliptic Curves - curve form and coord… Viktor Dukhovni
- Re: [Cfrg] Elliptic Curves - curve form and coord… Andrey Jivsov
- Re: [Cfrg] Elliptic Curves - curve form and coord… Michael Hamburg
- Re: [Cfrg] Elliptic Curves - curve form and coord… Rene Struik
- Re: [Cfrg] Elliptic Curves - curve form and coord… Rene Struik
- Re: [Cfrg] Elliptic Curves - curve form and coord… D. J. Bernstein
- Re: [Cfrg] Elliptic Curves - curve form and coord… Rene Struik
- Re: [Cfrg] Elliptic Curves - curve form and coord… Ilari Liusvaara
- Re: [Cfrg] Elliptic Curves - curve form and coord… Alyssa Rowan
- Re: [Cfrg] Elliptic Curves - curve form and coord… Alyssa Rowan
- Re: [Cfrg] Elliptic Curves - curve form and coord… Michael Hamburg
- Re: [Cfrg] Elliptic Curves - curve form and coord… Andrey Jivsov
- Re: [Cfrg] Elliptic Curves - curve form and coord… Ilari Liusvaara
- [Cfrg] (flaws with Curve25519 DH function, if one… Rene Struik
- Re: [Cfrg] (flaws with Curve25519 DH function, if… Ilari Liusvaara
- Re: [Cfrg] Elliptic Curves - curve form and coord… Viktor Dukhovni
- Re: [Cfrg] Elliptic Curves - curve form and coord… Watson Ladd
- [Cfrg] (flaws with Curve25519 DH function, if one… Rene Struik
- Re: [Cfrg] (flaws with Curve25519 DH function, if… Watson Ladd
- Re: [Cfrg] Elliptic Curves - curve form and coord… Michael Hamburg
- Re: [Cfrg] Elliptic Curves - curve form and coord… Nico Williams
- Re: [Cfrg] (flaws with Curve25519 DH function, if… David Leon Gil
- Re: [Cfrg] (flaws with Curve25519 DH function, if… Viktor Dukhovni
- Re: [Cfrg] (flaws with Curve25519 DH function, if… Nico Williams
- Re: [Cfrg] (flaws with Curve25519 DH function, if… CodesInChaos
- Re: [Cfrg] (flaws with Curve25519 DH function, if… Salz, Rich
- Re: [Cfrg] (flaws with Curve25519 DH function, if… Watson Ladd
- Re: [Cfrg] (flaws with Curve25519 DH function, if… Ilari Liusvaara
- Re: [Cfrg] (flaws with Curve25519 DH function, if… CodesInChaos
- Re: [Cfrg] (flaws with Curve25519 DH function, if… Watson Ladd
- Re: [Cfrg] Elliptic Curves - curve form and coord… Alexey Melnikov
- [Cfrg] Elliptic Curves - curve form and coordinat… Alexey Melnikov
- Re: [Cfrg] Elliptic Curves - curve form and coord… Watson Ladd
- Re: [Cfrg] Elliptic Curves - curve form and coord… Dan Brown
- Re: [Cfrg] Elliptic Curves - curve form and coord… Alyssa Rowan
- Re: [Cfrg] Elliptic Curves - curve form and coord… Phillip Hallam-Baker
- Re: [Cfrg] Elliptic Curves - curve form and coord… Tony Arcieri
- Re: [Cfrg] Elliptic Curves - curve form and coord… Ilari Liusvaara
- Re: [Cfrg] Elliptic Curves - curve form and coord… Mike Hamburg
- Re: [Cfrg] Elliptic Curves - curve form and coord… Nadim Kobeissi
- Re: [Cfrg] Elliptic Curves - curve form and coord… Adam Langley
- Re: [Cfrg] Elliptic Curves - curve form and coord… Andrey Jivsov
- Re: [Cfrg] Elliptic Curves - curve form and coord… Adam Langley
- Re: [Cfrg] Elliptic Curves - curve form and coord… Phillip Hallam-Baker
- Re: [Cfrg] Elliptic Curves - curve form and coord… Paul Lambert
- Re: [Cfrg] Elliptic Curves - curve form and coord… Andrey Jivsov
- Re: [Cfrg] Elliptic Curves - curve form and coord… Salz, Rich
- Re: [Cfrg] Elliptic Curves - curve form and coord… Adam Langley
- Re: [Cfrg] Elliptic Curves - curve form and coord… Nico Williams
- Re: [Cfrg] Elliptic Curves - curve form and coord… Michael Hamburg
- Re: [Cfrg] Elliptic Curves - curve form and coord… Michael Hamburg
- Re: [Cfrg] Elliptic Curves - curve form and coord… Dan Brown
- Re: [Cfrg] Elliptic Curves - curve form and coord… Andrey Jivsov
- Re: [Cfrg] Elliptic Curves - curve form and coord… Paterson, Kenny
- Re: [Cfrg] Elliptic Curves - curve form and coord… Andrey Jivsov
- Re: [Cfrg] Elliptic Curves - curve form and coord… Michael Hamburg
- Re: [Cfrg] Elliptic Curves - curve form and coord… Andrey Jivsov
- Re: [Cfrg] Elliptic Curves - curve form and coord… Jakob Breier
- Re: [Cfrg] Elliptic Curves - curve form and coord… Phillip Hallam-Baker
- Re: [Cfrg] Elliptic Curves - curve form and coord… Rene Struik
- Re: [Cfrg] Elliptic Curves - curve form and coord… Watson Ladd
- Re: [Cfrg] Elliptic Curves - curve form and coord… Rene Struik
- Re: [Cfrg] Elliptic Curves - curve form and coord… Nico Williams
- Re: [Cfrg] Elliptic Curves - curve form and coord… Watson Ladd
- Re: [Cfrg] Elliptic Curves - curve form and coord… Rene Struik
- Re: [Cfrg] Elliptic Curves - curve form and coord… Jakob Breier
- Re: [Cfrg] Elliptic Curves - curve form and coord… Ilari Liusvaara
- Re: [Cfrg] Elliptic Curves - curve form and coord… Watson Ladd
- Re: [Cfrg] Elliptic Curves - curve form and coord… Andrey Jivsov
- Re: [Cfrg] Elliptic Curves - curve form and coord… Rene Struik
- Re: [Cfrg] Elliptic Curves - curve form and coord… Michael Hamburg
- Re: [Cfrg] Elliptic Curves - curve form and coord… Salz, Rich
- Re: [Cfrg] Elliptic Curves - curve form and coord… Andrey Jivsov
- Re: [Cfrg] Elliptic Curves - curve form and coord… Michael Hamburg