IETF Logo Mail Archive

Re: [TLS] weird ECDSA interop problem with cloudflare/nginx

Ilari Liusvaara <ilariliusvaara@welho.com> Mon, 25 July 2016 21:00 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 82DF512D08E for <tls@ietfa.amsl.com>; Mon, 25 Jul 2016 14:00:34 -0700 (PDT)
X-Virus-Scanned: amavisd-new at amsl.com
X-Spam-Flag: NO
X-Spam-Score: -3.187
X-Spam-Level:
X-Spam-Status: No, score=-3.187 tagged_above=-999 required=5 tests=[BAYES_00=-1.9, RP_MATCHES_RCVD=-1.287] 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 ScB9VlIs8Czc for <tls@ietfa.amsl.com>; Mon, 25 Jul 2016 14:00:28 -0700 (PDT)
Received: from welho-filter1.welho.com (welho-filter1.welho.com [83.102.41.23]) by ietfa.amsl.com (Postfix) with ESMTP id B9AA612DA25 for <tls@ietf.org>; Mon, 25 Jul 2016 14:00:28 -0700 (PDT)
Received: from localhost (localhost [127.0.0.1]) by welho-filter1.welho.com (Postfix) with ESMTP id BC4F97B94 for <tls@ietf.org>; Tue, 26 Jul 2016 00:00:26 +0300 (EEST)
X-Virus-Scanned: Debian amavisd-new at pp.htv.fi
Received: from welho-smtp3.welho.com ([IPv6:::ffff:83.102.41.86]) by localhost (welho-filter1.welho.com [::ffff:83.102.41.23]) (amavisd-new, port 10024) with ESMTP id ULYLD1jaTOju for <tls@ietf.org>; Tue, 26 Jul 2016 00:00:26 +0300 (EEST)
Received: from LK-Perkele-V2 (87-100-177-32.bb.dnainternet.fi [87.100.177.32]) (using TLSv1 with cipher ECDHE-RSA-AES256-SHA (256/256 bits)) (No client certificate requested) by welho-smtp3.welho.com (Postfix) with ESMTPSA id 157152310 for <tls@ietf.org>; Tue, 26 Jul 2016 00:00:26 +0300 (EEST)
Date: Tue, 26 Jul 2016 00:00:21 +0300
From: Ilari Liusvaara <ilariliusvaara@welho.com>
To: tls@ietf.org
Message-ID: <20160725210021.GA17403@LK-Perkele-V2.elisa-laajakaista.fi>
References: <20160725190849.728521A508@ld9781.wdf.sap.corp> <05880081-C790-4D4C-9FF0-BA29F47C010A@dukhovni.org>
MIME-Version: 1.0
Content-Type: text/plain; charset="utf-8"
Content-Disposition: inline
In-Reply-To: <05880081-C790-4D4C-9FF0-BA29F47C010A@dukhovni.org>
User-Agent: Mutt/1.6.0 (2016-04-01)
Sender: ilariliusvaara@welho.com
Archived-At: <https://mailarchive.ietf.org/arch/msg/tls/U7C-3rWZmtKMvVUaDgcapajiUhk>
Subject: Re: [TLS] weird ECDSA interop problem with cloudflare/nginx
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, 25 Jul 2016 21:00:34 -0000

On Mon, Jul 25, 2016 at 04:36:27PM -0400, Viktor Dukhovni wrote:
> 
> > On Jul 25, 2016, at 3:08 PM, Martin Rex <mrex@sap.com> wrote:
> > 
> > specifically, after the FF update, this new TLS ciphersuite:
> > 
> >   security.ssl3.ecdhe_ecdsa_aes_128_gcm_sha256  (0xcc, 0xa9)
> > 
> > was the only ECDSA cipher suite enabled in my Firefox 47.0.1, and this
> > kills connectivity (TLS handshake_failure alert) with regmedia.co.uk.
> 
> OpenSSL lists "CC, A9" as:
> 
> 0xCC,0xA9 - ECDHE-ECDSA-CHACHA20-POLY1305 TLSv1.2 Kx=ECDH     Au=ECDSA Enc=CHACHA20/POLY1305(256) Mac=AEAD

I wonder what is happening is that having ECDSA ciphersuite enabled
causes Firefox to include the ECDSA signatures in signature_algorithms
and the server end sees ECDSA supported, tries to choose that, but
then blows up when it does not find any enabled ciphersuites it knows
that support ECDSA...



-Ilari

v2.23.0 | Report a Bug | By Email