Re: [TLS] analysis of wider impact of TLS1.3 replayabe data

Ilari Liusvaara <ilariliusvaara@welho.com> Mon, 14 March 2016 18:41 UTC

Return-Path: <ilariliusvaara@welho.com>
X-Original-To: tls@ietfa.amsl.com
Delivered-To: tls@ietfa.amsl.com
Received: from localhost (localhost [127.0.0.1]) by ietfa.amsl.com (Postfix) with ESMTP id 01E8712D726 for <tls@ietfa.amsl.com>; Mon, 14 Mar 2016 11:41:59 -0700 (PDT)
X-Virus-Scanned: amavisd-new at amsl.com
X-Spam-Flag: NO
X-Spam-Score: -1.901
X-Spam-Level:
X-Spam-Status: No, score=-1.901 tagged_above=-999 required=5 tests=[BAYES_00=-1.9, RP_MATCHES_RCVD=-0.001] autolearn=ham autolearn_force=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 BccROp8WNuib for <tls@ietfa.amsl.com>; Mon, 14 Mar 2016 11:41:56 -0700 (PDT)
Received: from welho-filter2.welho.com (welho-filter2.welho.com [83.102.41.24]) by ietfa.amsl.com (Postfix) with ESMTP id 9F09B12D6F8 for <tls@ietf.org>; Mon, 14 Mar 2016 11:41:56 -0700 (PDT)
Received: from localhost (localhost [127.0.0.1]) by welho-filter2.welho.com (Postfix) with ESMTP id 2DC751EE3; Mon, 14 Mar 2016 20:41:55 +0200 (EET)
X-Virus-Scanned: Debian amavisd-new at pp.htv.fi
Received: from welho-smtp1.welho.com ([IPv6:::ffff:83.102.41.84]) by localhost (welho-filter2.welho.com [::ffff:83.102.41.24]) (amavisd-new, port 10024) with ESMTP id eEsJJUz5CBik; Mon, 14 Mar 2016 20:41:54 +0200 (EET)
Received: from LK-Perkele-V2 (87-100-143-35.bb.dnainternet.fi [87.100.143.35]) (using TLSv1 with cipher ECDHE-RSA-AES256-SHA (256/256 bits)) (No client certificate requested) by welho-smtp1.welho.com (Postfix) with ESMTPSA id AEC4AC4; Mon, 14 Mar 2016 20:41:54 +0200 (EET)
Date: Mon, 14 Mar 2016 20:41:53 +0200
From: Ilari Liusvaara <ilariliusvaara@welho.com>
To: Colm =?utf-8?Q?MacC=C3=A1rthaigh?= <colm@allcosts.net>
Message-ID: <20160314184153.GA14692@LK-Perkele-V2.elisa-laajakaista.fi>
References: <56E54B85.4050204@cs.tcd.ie> <CAAF6GDeOFNgNt_+O=gkBedqP55qdnOpKKQ9-HOQ6i7fYpLanqw@mail.gmail.com> <CABcZeBP+1vmfNmmAr1+CcXUkNA0yS6CGa7La7ekQgtyFkiFtSQ@mail.gmail.com> <CAAF6GDfcrZyeLo_n9LEPHzXTPSXv8iRWBiNebARYYAKp9CfQmQ@mail.gmail.com>
MIME-Version: 1.0
Content-Type: text/plain; charset=utf-8
Content-Disposition: inline
Content-Transfer-Encoding: 8bit
In-Reply-To: <CAAF6GDfcrZyeLo_n9LEPHzXTPSXv8iRWBiNebARYYAKp9CfQmQ@mail.gmail.com>
User-Agent: Mutt/1.5.24 (2015-08-30)
Sender: ilariliusvaara@welho.com
Archived-At: <http://mailarchive.ietf.org/arch/msg/tls/p1WxlkOTRMaWlvwcRk4MD8f8TPM>
Cc: "tls@ietf.org" <tls@ietf.org>
Subject: Re: [TLS] analysis of wider impact of TLS1.3 replayabe data
X-BeenThere: tls@ietf.org
X-Mailman-Version: 2.1.17
Precedence: list
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: Mon, 14 Mar 2016 18:41:59 -0000

On Mon, Mar 14, 2016 at 09:15:17AM -0700, Colm MacCárthaigh wrote:
> On Mon, Mar 14, 2016 at 4:32 AM, Eric Rescorla <ekr@rtfm.com>; wrote:
> 
> > For 1. Raw data throughput could be improved by envelope encrypting the
> > early data; and transferring the envelope key only once the session has
> > been fully authenticated
> >

Unfortunately, that doesn't work for things like protocol banners or
other things that can be sent in 0-RTT and replied to in 0.5-RTT.


(Also, with regards to my comment about cryptographic screwedness,
such screwedness is not inherent in DH-0RTT, but is consequence of
the current implementation).


-Ilari