Re: [TLS] RESOLVED (Re: [sasl] lasgt call comments (st Call:
Martin Rex <Martin.Rex@sap.com> Mon, 02 November 2009 16:48 UTC
Return-Path: <Martin.Rex@sap.com>
X-Original-To: tls@core3.amsl.com
Delivered-To: tls@core3.amsl.com
Received: from localhost (localhost [127.0.0.1]) by core3.amsl.com (Postfix) with ESMTP id 0ACB228C129; Mon, 2 Nov 2009 08:48:28 -0800 (PST)
X-Virus-Scanned: amavisd-new at amsl.com
X-Spam-Flag: NO
X-Spam-Score: -6.183
X-Spam-Level:
X-Spam-Status: No, score=-6.183 tagged_above=-999 required=5 tests=[AWL=0.066, BAYES_00=-2.599, HELO_EQ_DE=0.35, RCVD_IN_DNSWL_MED=-4]
Received: from mail.ietf.org ([64.170.98.32]) by localhost (core3.amsl.com [127.0.0.1]) (amavisd-new, port 10024) with ESMTP id Fbkr8vx-B1p6; Mon, 2 Nov 2009 08:48:27 -0800 (PST)
Received: from smtpde01.sap-ag.de (smtpde01.sap-ag.de [155.56.68.171]) by core3.amsl.com (Postfix) with ESMTP id DE27C28C0ED; Mon, 2 Nov 2009 08:48:26 -0800 (PST)
Received: from mail.sap.corp by smtpde01.sap-ag.de (26) with ESMTP id nA2GmiQQ020042 (version=TLSv1/SSLv3 cipher=DHE-RSA-AES256-SHA bits=256 verify=NO); Mon, 2 Nov 2009 17:48:44 +0100 (MET)
From: Martin Rex <Martin.Rex@sap.com>
Message-Id: <200911021648.nA2Gmida005474@fs4113.wdf.sap.corp>
To: Nicolas.Williams@sun.com
Date: Mon, 02 Nov 2009 17:48:44 +0100
In-Reply-To: <20091030223647.GO1105@Sun.COM> from "Nicolas Williams" at Oct 30, 9 05:36:48 pm
MIME-Version: 1.0
Content-Type: text/plain; charset="ISO-8859-1"
Content-Transfer-Encoding: 8bit
X-Scanner: Virus Scanner virwal05
X-SAP: out
Cc: channel-binding@ietf.org, sasl@ietf.org, tls@ietf.org
Subject: Re: [TLS] RESOLVED (Re: [sasl] lasgt call comments (st Call:
X-BeenThere: tls@ietf.org
X-Mailman-Version: 2.1.9
Precedence: list
Reply-To: mrex@sap.com
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/listinfo/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: Mon, 02 Nov 2009 16:48:28 -0000
Nicolas Williams wrote: > > Another problem that Larry has is that in his implementation what I call > a "TLS connection" is called a "security context", and if the > application re-handshakes (e.g., to authenticate a user) then the result > is a second security context -- we need to be extra clear that it's the > client Finished message from the _first_ "security context" that we're > after. Microsoft's implementation (which could be the one referred to by Larry's implementation) has a silly design flaw in its TLS renogiation, and I'm not sure that the previous text is a way to fix it. It is possible to configure Microsoft IIS in a fashion so that it will first perform a TLS handshake with a server-only authentication, and after having received the HTTP request, it will re-negotiate and ask for a client certificate. In the ClientHello, the client will send no TLS session ID (since the purpose is renegotiation -- aka a full TLS handshake. Microsoft IIS will send back a ServerHello with an entirely new TLS session ID. In my TLS clients, I will drop TLS sessions from the client-side cache for which the server asks for re-negotiation (actually replace them with the resulting renegotiated TLS session). Unfortunately, this doesn't save a TLS handshake on the next connect, Microsoft IIS will force another renegotiation when that re-negotiated session is resumed, resulting in yet another new TLS session. >From my experience, it is possible to TLS resume both, the original and the renegotiated session when Microsoft IIS is the server, and it will force through re-negotiation on both. So an IIS configured like that will artificially inflate its server-side session cache and impose unnecessary re-negotiations on the TLS client and on itself. And btw. Channel Binding at the application layer and transparent TLS-session renegotiation at the TLS layer appear somewhere between hard-to-do and mutually exclusive--in case that the TLS session renegotiation happens totally transparent to the application. -Martin
- [TLS] Last Call: draft-altman-tls-channel-binding… The IESG
- Re: [TLS] lasgt call comments (st Call: draft-alt… Larry Zhu
- Re: [TLS] [sasl] lasgt call comments (st Call: dr… Pasi.Eronen
- Re: [TLS] lasgt call comments (st Call: draft-alt… Simon Josefsson
- Re: [TLS] lasgt call comments (st Call: draft-alt… Simon Josefsson
- Re: [TLS] [sasl] lasgt call comments (st Call: dr… Nicolas Williams
- Re: [TLS] [sasl] lasgt call comments (st Call: dr… Nicolas Williams
- Re: [TLS] [sasl] lasgt call comments (st Call: Martin Rex
- Re: [TLS] [sasl] lasgt call comments (st Call: dr… Larry Zhu
- Re: [TLS] [sasl] lasgt call comments (st Call: Nicolas Williams
- Re: [TLS] [sasl] lasgt call comments (st Call: dr… Larry Zhu
- Re: [TLS] [sasl] lasgt call comments (st Call: dr… Nicolas Williams
- [TLS] RESOLVED (Re: [sasl] lasgt call comments (s… Nicolas Williams
- Re: [TLS] RESOLVED (Re: [sasl] lasgt call comment… Martin Rex
- Re: [TLS] RESOLVED (Re: [sasl] lasgt call comment… Simon Josefsson
- Re: [TLS] RESOLVED (Re: [sasl] lasgt call comment… Martin Rex
- Re: [TLS] RESOLVED (Re: [sasl] lasgt call comment… Martin Rex
- Re: [TLS] RESOLVED (Re: [sasl] lasgt call comment… Peter Gutmann
- Re: [TLS] RESOLVED (Re: [sasl] lasgt call comment… Martin Rex
- Re: [TLS] RESOLVED (Re: [sasl] lasgt call comment… Nicolas Williams
- Re: [TLS] [CHANNEL-BINDING] RESOLVED (Re: [sasl] … Nicolas Williams
- [TLS] Unrelated (Re: [CHANNEL-BINDING] RESOLVED (… Nicolas Williams
- Re: [TLS] [CHANNEL-BINDING] RESOLVED (Re: [sasl] … Nicolas Williams
- Re: [TLS] Unrelated (Re: [CHANNEL-BINDING] RESOLV… Martin Rex
- Re: [TLS] [CHANNEL-BINDING] Unrelated (Re: RESOLV… Nicolas Williams
- Re: [TLS] RESOLVED (Re: [sasl] lasgt call comment… Martin Rex
- Re: [TLS] [CHANNEL-BINDING] RESOLVED (Re: [sasl] … Martin Rex
- Re: [TLS] RESOLVED (Re: [sasl] lasgt call comment… Pasi.Eronen
- Re: [TLS] RESOLVED (Re: [sasl] lasgt call comment… Pasi.Eronen
- Re: [TLS] lasgt call comments (st Call: draft-alt… Pasi.Eronen
- Re: [TLS] lasgt call comments (st Call: draft-alt… Simon Josefsson
- Re: [TLS] RESOLVED (Re: [sasl] lasgt call comment… Nicolas Williams
- Re: [TLS] [sasl] lasgt call comments (st Call: dr… Nicolas Williams
- Re: [TLS] RESOLVED (Re: [sasl] lasgt call comment… Michael D'Errico
- Re: [TLS] [sasl] lasgt call comments (st Call: dr… Nicolas Williams
- Re: [TLS] [CHANNEL-BINDING] RESOLVED (Re: [sasl] … Nicolas Williams
- Re: [TLS] RESOLVED (Re: [sasl] lasgt call comment… Nicolas Williams
- Re: [TLS] [CHANNEL-BINDING] RESOLVED (Re: [sasl] … Jeffrey Hutzelman
- Re: [TLS] [CHANNEL-BINDING] RESOLVED (Re: [sasl] … Sam Hartman
- Re: [TLS] [CHANNEL-BINDING] RESOLVED (Re: [sasl] … Nicolas Williams
- Re: [TLS] lasgt call comments (st Call: draft-alt… Simon Josefsson
- Re: [TLS] lasgt call comments (st Call: draft-alt… Nicolas Williams
- Re: [TLS] RESOLVED (Re: [sasl] lasgt call comment… Larry Zhu
- [TLS] New Problem (Was: Last Call: draft-altman-t… Nicolas Williams
- Re: [TLS] New Problem (Was: Last Call: draft-altm… Larry Zhu
- Re: [TLS] [CHANNEL-BINDING] New Problem (Was: Las… Nicolas Williams