Re: [http-auth] Why update Digest Auth?

Rifaat Shekh-Yusef <rifaat.ietf@gmail.com> Mon, 22 July 2013 10:55 UTC

Return-Path: <rifaat.ietf@gmail.com>
X-Original-To: http-auth@ietfa.amsl.com
Delivered-To: http-auth@ietfa.amsl.com
Received: from localhost (localhost [127.0.0.1]) by ietfa.amsl.com (Postfix) with ESMTP id D0B1B21F999B for <http-auth@ietfa.amsl.com>; Mon, 22 Jul 2013 03:55:36 -0700 (PDT)
X-Virus-Scanned: amavisd-new at amsl.com
X-Spam-Flag: NO
X-Spam-Score: -1.813
X-Spam-Level:
X-Spam-Status: No, score=-1.813 tagged_above=-999 required=5 tests=[AWL=-0.610, BAYES_00=-2.599, MIME_QP_LONG_LINE=1.396]
Received: from mail.ietf.org ([12.22.58.30]) by localhost (ietfa.amsl.com [127.0.0.1]) (amavisd-new, port 10024) with ESMTP id zFCFqTp-jiqs for <http-auth@ietfa.amsl.com>; Mon, 22 Jul 2013 03:55:10 -0700 (PDT)
Received: from mail-ee0-x22c.google.com (mail-ee0-x22c.google.com [IPv6:2a00:1450:4013:c00::22c]) by ietfa.amsl.com (Postfix) with ESMTP id 1FB2621E8086 for <http-auth@ietf.org>; Mon, 22 Jul 2013 03:51:28 -0700 (PDT)
Received: by mail-ee0-f44.google.com with SMTP id c13so3761788eek.31 for <http-auth@ietf.org>; Mon, 22 Jul 2013 03:51:19 -0700 (PDT)
DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20120113; h=references:mime-version:in-reply-to:content-type :content-transfer-encoding:message-id:cc:x-mailer:from:subject:date :to; bh=uMqOfrHBN9MySKr0IjG2W8RGmjQGc1PcuJ28hYpt+QU=; b=jWigywJwifqYH500vWwZKStFWP5Gsh6Smtk8+Yu2n/bURWUafXTXEYFOAZPs4rS1fN NQScQx0aM4r8TI872ZuWConlxy5ziPF37XmN/IQM4fre24zgOkwYl4khTWSkzNZTK4Pm htm69wtvziy5qfHoRNetkGUi+rwsOWQdO9hYFgXZm2FvsijGgreP1Q9uRwn1xfDL6upN MoV5khBYERlbfyx2AdfERSUdWDzfkKDNtsttzBnqzGlq4NOIodY1YTT0cWmsdZKyEdpO WbG8wq7PoiO3sJz4cEyU2AvQpHRA6N/Oysevv30PyoEjrCMI8c7fiMkEmhZ9Lq9xau+y L3XQ==
X-Received: by 10.15.43.11 with SMTP id w11mr27185855eev.27.1374490279755; Mon, 22 Jul 2013 03:51:19 -0700 (PDT)
Received: from [192.168.1.15] (93-173-50-241.bb.netvision.net.il. [93.173.50.241]) by mx.google.com with ESMTPSA id i2sm49887671eeu.4.2013.07.22.03.51.14 for <multiple recipients> (version=TLSv1 cipher=ECDHE-RSA-RC4-SHA bits=128/128); Mon, 22 Jul 2013 03:51:18 -0700 (PDT)
References: <51EABBDB.2090401@gmail.com> <4613980CFC78314ABFD7F85CC302772111A9EE0E@DAG-EX10.ad.checkpoint.com>
Mime-Version: 1.0 (1.0)
In-Reply-To: <4613980CFC78314ABFD7F85CC302772111A9EE0E@DAG-EX10.ad.checkpoint.com>
Content-Type: text/plain; charset="us-ascii"
Content-Transfer-Encoding: quoted-printable
Message-Id: <C246BE86-0721-4259-8611-4DD68101B95D@gmail.com>
X-Mailer: iPhone Mail (10B329)
From: Rifaat Shekh-Yusef <rifaat.ietf@gmail.com>
Date: Mon, 22 Jul 2013 13:51:07 +0300
To: Yoav Nir <ynir@checkpoint.com>
Cc: HTTP Auth WG <http-auth@ietf.org>
Subject: Re: [http-auth] Why update Digest Auth?
X-BeenThere: http-auth@ietf.org
X-Mailman-Version: 2.1.12
Precedence: list
List-Id: HTTP authentication methods <http-auth.ietf.org>
List-Unsubscribe: <https://www.ietf.org/mailman/options/http-auth>, <mailto:http-auth-request@ietf.org?subject=unsubscribe>
List-Archive: <http://www.ietf.org/mail-archive/web/http-auth>
List-Post: <mailto:http-auth@ietf.org>
List-Help: <mailto:http-auth-request@ietf.org?subject=help>
List-Subscribe: <https://www.ietf.org/mailman/listinfo/http-auth>, <mailto:http-auth-request@ietf.org?subject=subscribe>
X-List-Received-Date: Mon, 22 Jul 2013 10:55:49 -0000

I do not like the idea of canceling the Digest work for the following reasons:

1. Digest is used with SIP protocol, and I am not sure the widely used Digest mechanism in SIP networks will be replaced with any if the new proposals.

2. This was already discussed during the discussion on the charter, and it seems a bit late to reopen that right now.

3. I think that the adopters of the new mechanisms should be motivated by the merit of the new mechanisms, not by us not updating Digest.

4. Some of the adopters of Digest might be satisfied with the Digest as it fulfills their need, and might not be interested in a "better" solution for their network.

To address the timeline point that Stephen has raised, I think that the agility work should be done fairly soon as I do not see any major challenges at this stage.
 
Regards,
 Rifaat

Sent from my iPhone

On 2013-07-22, at 12:16 PM, Yoav Nir <ynir@checkpoint.com> wrote:

> I'm not totally opposed, but if we replace Digest with some ZKPP, it's not Digest any more. 
> 
> Two of our experimental drafts are "better digests" - MutualAuth and SCRAM. MutualAuth is mature, has implementations, and I don't see why it shouldn't be ready to progress almost as fast as Digest.
> 
> Do you think that enterprises would require "Digest" rather than "MutualAuth" or "SCRAM" just because it's called "Digest"?
> 
> Hopefully these new methods will also support international user names and passwords (because specifying a user authentication method is 2013 that does not support non-English names is even sillier than specifying one that relies on MD5 for security). Then it's up to the enterprises to decide what they want to require vendors to implement.
> 
> Yoav
> 
> -----Original Message-----
> From: http-auth-bounces@ietf.org [mailto:http-auth-bounces@ietf.org] On Behalf Of Yaron Sheffer
> Sent: Saturday, July 20, 2013 7:34 PM
> To: HTTP Auth WG
> Subject: [http-auth] Why update Digest Auth?
> 
> Sorry for questioning the group's charter, but this keeps bugging me:
> 
> I'm assuming this WG will publish two Standards Track RFCs, updating Basic and Digest Auth. And a pile of Experimental RFCs with all sorts of lovely state-of-the-art crypto.
> 
> Enterprises will require vendors to implement the updated Basic and Digest, and in a few years' time we will end up with the worlds' 
> browsers and Web servers supporting Basic and Digest Auth with I18N and (for Digest) crypto agility. Almost nobody will implement the other drafts.
> 
> In addition, the websec WG will hopefully work on "session continuation", which will extend the authentication to the whole session in a better way than cookies, and will provide channel binding. Assuming much of the Internet's traffic will remain unencrypted for years, this will be "good enough" security for this traffic. But, it won't work with Digest (because it is not "key generating", to borrow an EAP term).
> 
> Now my question: we are telling implementors to upgrade Digest to gain I18N (and the algorithm agility, which in this case is mostly security theater, because when using short passwords we remain vulnerable to a dictionary attack anyway). Why not tell them *instead* to move to Digest-v2, which is dictionary attack resistant? Digest-v2 could be based on EKE or SRP, or maybe on draft-oiwa-http-mutualauth, and will support session continuation.
> 
> Seems to me this would be a much better use of our time, as well as implementors' energy.
> 
> Thanks,
>     Yaron
> 
> _______________________________________________
> http-auth mailing list
> http-auth@ietf.org
> https://www.ietf.org/mailman/listinfo/http-auth