Re: [TLS] DSA should die

Viktor Dukhovni <ietf-dane@dukhovni.org> Thu, 02 April 2015 01:01 UTC

Return-Path: <ietf-dane@dukhovni.org>
X-Original-To: tls@ietfa.amsl.com
Delivered-To: tls@ietfa.amsl.com
Received: from localhost (ietfa.amsl.com [127.0.0.1]) by ietfa.amsl.com (Postfix) with ESMTP id 7C0B71AD068 for <tls@ietfa.amsl.com>; Wed, 1 Apr 2015 18:01:55 -0700 (PDT)
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] 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 VlMAqghy8q5h for <tls@ietfa.amsl.com>; Wed, 1 Apr 2015 18:01:54 -0700 (PDT)
Received: from mournblade.imrryr.org (mournblade.imrryr.org [38.117.134.19]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by ietfa.amsl.com (Postfix) with ESMTPS id 014841AD067 for <tls@ietf.org>; Wed, 1 Apr 2015 18:01:53 -0700 (PDT)
Received: by mournblade.imrryr.org (Postfix, from userid 1034) id E8E32283031; Thu, 2 Apr 2015 01:01:52 +0000 (UTC)
Date: Thu, 2 Apr 2015 01:01:52 +0000
From: Viktor Dukhovni <ietf-dane@dukhovni.org>
To: tls@ietf.org
Message-ID: <20150402010152.GU17637@mournblade.imrryr.org>
References: <20150401201221.163745c2@pc1.fritz.box> <20150402002646.GR17637@mournblade.imrryr.org> <551C9008.5030605@cs.tcd.ie>
MIME-Version: 1.0
Content-Type: text/plain; charset=us-ascii
Content-Disposition: inline
In-Reply-To: <551C9008.5030605@cs.tcd.ie>
User-Agent: Mutt/1.5.23 (2014-03-12)
Archived-At: <http://mailarchive.ietf.org/arch/msg/tls/5A0pP9a7tne0pbIKuJnlCeZ6GJs>
Subject: Re: [TLS] DSA should die
X-BeenThere: tls@ietf.org
X-Mailman-Version: 2.1.15
Precedence: list
Reply-To: tls@ietf.org
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: <http://www.ietf.org/mail-archive/web/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: Thu, 02 Apr 2015 01:01:55 -0000

On Thu, Apr 02, 2015 at 01:40:40AM +0100, Stephen Farrell wrote:

> <no-hats-except-the-330+-ciphersuites-is-crap-hat>
> 
> Here's a suggestion: why pick 'em off one by one? How about
> creating a new registry that only includes stuff we think is
> really good for TLS1.3?
> 
> Personally, I'd go further and argue that the new registry
> only specify the TLS 1.3 MTIs, but that's a different question:-)

The problem is that leaves SRP and the like out in the cold.  So
there would need to be few such lists, but that's fine, a client
doing SRP/PSS/... would only advertise SRP/PSS-capable cipher-suites,
and client with no SRP/PSS/... shared secrets would not advertise
any of them.

So that means a short list per authentication trust-model.

    * A list for PKI TLS.

    * A list for anon TLS (that includes the PKI list, for
      interop, and the client will ignore the server's cert).

    * A list for SRP.

    * A list for PSS.

Each list is short, and any client uses just one list.

-- 
	Viktor.