IETF Logo Mail Archive

Re: [TLS] A closer look at ROBOT, BB Attacks, timing attacks in general, and what we can do in TLS

Ilari Liusvaara <ilariliusvaara@welho.com> Fri, 15 December 2017 18:49 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 918B1126E3A for <tls@ietfa.amsl.com>; Fri, 15 Dec 2017 10:49:58 -0800 (PST)
X-Virus-Scanned: amavisd-new at amsl.com
X-Spam-Flag: NO
X-Spam-Score: -1.9
X-Spam-Level:
X-Spam-Status: No, score=-1.9 tagged_above=-999 required=5 tests=[BAYES_00=-1.9, RCVD_IN_DNSWL_NONE=-0.0001] 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 WnM6MNpEQBun for <tls@ietfa.amsl.com>; Fri, 15 Dec 2017 10:49:56 -0800 (PST)
Received: from welho-filter1.welho.com (welho-filter1.welho.com [83.102.41.23]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by ietfa.amsl.com (Postfix) with ESMTPS id 43AA1124BAC for <tls@ietf.org>; Fri, 15 Dec 2017 10:49:56 -0800 (PST)
Received: from localhost (localhost [127.0.0.1]) by welho-filter1.welho.com (Postfix) with ESMTP id AD68D53726; Fri, 15 Dec 2017 20:49:54 +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-filter1.welho.com [::ffff:83.102.41.23]) (amavisd-new, port 10024) with ESMTP id Dzdf8OPzqqR0; Fri, 15 Dec 2017 20:49:54 +0200 (EET)
Received: from LK-Perkele-VII (87-92-19-27.bb.dnainternet.fi [87.92.19.27]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by welho-smtp1.welho.com (Postfix) with ESMTPSA id 5911928B; Fri, 15 Dec 2017 20:49:51 +0200 (EET)
Date: Fri, 15 Dec 2017 20:49:51 +0200
From: Ilari Liusvaara <ilariliusvaara@welho.com>
To: Andrei Popov <Andrei.Popov@microsoft.com>
Cc: Eric Rescorla <ekr@rtfm.com>, "tls@ietf.org" <tls@ietf.org>
Message-ID: <20171215184951.GB17780@LK-Perkele-VII>
References: <20171215020116.04f9ae15@pc1> <CAAF6GDe79w9XH1GrGvvR-+=uEKfi6GczacUX3Jhy0dL_zW67-Q@mail.gmail.com> <20171215143057.GA17121@LK-Perkele-VII> <MWHPR21MB01897F29048C1B2AB66EA7488C0B0@MWHPR21MB0189.namprd21.prod.outlook.com> <20171215174628.GA17601@LK-Perkele-VII> <CABcZeBOsL0a0xHvVWEus_EY3mUNioaV9fsz89Gt+HeqdHpoyDw@mail.gmail.com> <CACsn0ckYPpp5nD2jj4Zmx=ZJvqWzHW0tmmXo-9JeKL45+pRUqw@mail.gmail.com> <CABcZeBPPozOsTxxJO63RmHwTr56Wucx6OYW=kvvhosRUHR1ctA@mail.gmail.com> <20171215183424.GA17780@LK-Perkele-VII> <MWHPR21MB01893A20A8D0812E880926568C0B0@MWHPR21MB0189.namprd21.prod.outlook.com>
MIME-Version: 1.0
Content-Type: text/plain; charset="utf-8"
Content-Disposition: inline
In-Reply-To: <MWHPR21MB01893A20A8D0812E880926568C0B0@MWHPR21MB0189.namprd21.prod.outlook.com>
User-Agent: Mutt/1.9.1 (2017-09-22)
Sender: ilariliusvaara@welho.com
Archived-At: <https://mailarchive.ietf.org/arch/msg/tls/bzHr_RklJMcXfxosV4VYetOvRG8>
Subject: Re: [TLS] A closer look at ROBOT, BB Attacks, timing attacks in general, and what we can do in TLS
X-BeenThere: tls@ietf.org
X-Mailman-Version: 2.1.22
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: Fri, 15 Dec 2017 18:49:58 -0000

On Fri, Dec 15, 2017 at 06:41:06PM +0000, Andrei Popov wrote:
> It's true, the migration will be slow, but IMHO it still makes sense
> to define and implement an alternative hash.

Agreed. However, on certificates front, we need a method to perform
backward-compatible algorithm transition. Because non-backward-
compatible ones are just too hard. As we have seen _twice_.

On TLS handshake hashes, the transitions are already backward-
compatible. But that does not mean the transition will be easy.




-Ilari

v2.23.0 | Report a Bug | By Email