[Cfrg] Fwd: Mail regarding draft-irtf-cfrg-chacha20-poly1305
Yoav Nir <ynir.ietf@gmail.com> Fri, 17 October 2014 16:25 UTC
Return-Path: <ynir.ietf@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 DF5E41A1BCE
for <cfrg@ietfa.amsl.com>; Fri, 17 Oct 2014 09:25:48 -0700 (PDT)
X-Virus-Scanned: amavisd-new at amsl.com
X-Spam-Flag: NO
X-Spam-Score: -2
X-Spam-Level:
X-Spam-Status: No, score=-2 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, SPF_PASS=-0.001] 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 EH1u86leX0jC for <cfrg@ietfa.amsl.com>;
Fri, 17 Oct 2014 09:25:47 -0700 (PDT)
Received: from mail-wi0-x236.google.com (mail-wi0-x236.google.com
[IPv6:2a00:1450:400c:c05::236])
(using TLSv1 with cipher ECDHE-RSA-RC4-SHA (128/128 bits))
(No client certificate requested)
by ietfa.amsl.com (Postfix) with ESMTPS id 309F41A1BA9
for <cfrg@irtf.org>; Fri, 17 Oct 2014 09:25:47 -0700 (PDT)
Received: by mail-wi0-f182.google.com with SMTP id n3so1702609wiv.15
for <cfrg@irtf.org>; Fri, 17 Oct 2014 09:25:45 -0700 (PDT)
DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20120113;
h=from:content-type:content-transfer-encoding:subject:date:references
:to:message-id:mime-version;
bh=OF3Sviv+mRvddck8TPYfSKFhEySIDrhIhCrvn2z1dgA=;
b=nXDaYhLqYPVuX/qbaTe1DTkuZd3/U/Wl8RLTDsP8rMAbVTqrrlVPAch1WGvmPrKW8o
1S1FHHBvAu7iHeCLF2UarHBQyaPVl47glduHpVyFQtVSFwfdzDAiRjbgEwHjeHiizi8l
stC9IY0QXX9siIzdBTWfwYmYYZZyGidhWmIH/uUQtccQVgnjfT3dreZCli1ZUY//2VDI
4tlC8VFecUUpWQLXQpxQMKGIDNi4vw+VE+WiFrDcExGEL9HyBoduBTJU/K6u18rq6Y5w
umpPaF7066hsSX1cM87Ue4gyTTlQjBTwI0LvjM6ASUW0NNxeidjBIozyUiCGbaF+rQXv
C9pA==
X-Received: by 10.194.122.71 with SMTP id lq7mr9253189wjb.66.1413563145817;
Fri, 17 Oct 2014 09:25:45 -0700 (PDT)
Received: from [192.168.1.104] (IGLD-84-228-54-205.inter.net.il.
[84.228.54.205])
by mx.google.com with ESMTPSA id i5sm2243544wjz.0.2014.10.17.09.25.44
for <cfrg@irtf.org>
(version=TLSv1 cipher=ECDHE-RSA-RC4-SHA bits=128/128);
Fri, 17 Oct 2014 09:25:45 -0700 (PDT)
From: Yoav Nir <ynir.ietf@gmail.com>
Content-Type: text/plain; charset=iso-8859-1
Content-Transfer-Encoding: 7bit
Date: Fri, 17 Oct 2014 19:25:43 +0300
References: <CE03DB3D7B45C245BCA0D2432779493605DE69@MX104CL02.corp.emc.com>
To: cfrg@irtf.org
Message-Id: <F9CF9D3B-799B-452E-8177-FB03BB611E7E@gmail.com>
Mime-Version: 1.0 (Mac OS X Mail 8.0 \(1990.1\))
X-Mailer: Apple Mail (2.1990.1)
Archived-At: http://mailarchive.ietf.org/arch/msg/cfrg/lCVpml8epydtnjfhuf1Vb_EzYls
Subject: [Cfrg] Fwd: Mail regarding draft-irtf-cfrg-chacha20-poly1305
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: Fri, 17 Oct 2014 16:25:49 -0000
Message from David Black: > This nonce reuse warning in Section 4 somewhat on the light side: > > Consequences of repeating a nonce: If a nonce is repeated, then both > the one-time Poly1305 key and the key-stream are identical between > the messages. This reveals the XOR of the plaintexts, because the > XOR of the plaintexts is equal to the XOR of the ciphertexts. > > Here's some blunter text that could be used as a model - this was driven > into RFC 7146 by the secdir reviewer (it applies to all stream ciphers > and all modes that behave like stream ciphers): > > Of particular interest are the security considerations concerning the > use of AES GCM [RFC4106] and AES GMAC [RFC4543]; both modes are > vulnerable to catastrophic forgery attacks if a nonce is ever > repeated with a given key. > > Thanks, > --David > ---------------------------------------------------- > David L. Black, Distinguished Engineer > EMC Corporation, 176 South St., Hopkinton, MA 01748 > +1 (508) 293-7953 FAX: +1 (508) 293-7786 > david.black@emc.com Mobile: +1 (978) 394-7754 > ----------------------------------------------------
- [Cfrg] Fwd: Mail regarding draft-irtf-cfrg-chacha… Yoav Nir
- Re: [Cfrg] Fwd: Mail regarding draft-irtf-cfrg-ch… Ilari Liusvaara