Return-Path: 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 10B3412D7C3 for ; Fri, 19 Aug 2016 06:03:28 -0700 (PDT) X-Virus-Scanned: amavisd-new at amsl.com X-Spam-Flag: NO X-Spam-Score: -5.447 X-Spam-Level: X-Spam-Status: No, score=-5.447 tagged_above=-999 required=5 tests=[BAYES_00=-1.9, DKIM_SIGNED=0.1, DKIM_VALID=-0.1, RCVD_IN_DNSWL_MED=-2.3, RP_MATCHES_RCVD=-1.247] autolearn=ham autolearn_force=no Authentication-Results: ietfa.amsl.com (amavisd-new); dkim=pass (2048-bit key) header.d=auckland.ac.nz 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 cPTW_8sO6NVc for ; Fri, 19 Aug 2016 06:03:26 -0700 (PDT) Received: from mx4.auckland.ac.nz (mx4.auckland.ac.nz [130.216.125.248]) (using TLSv1.2 with cipher RC4-SHA (128/128 bits)) (No client certificate requested) by ietfa.amsl.com (Postfix) with ESMTPS id 33A7B12B02B for ; Fri, 19 Aug 2016 06:03:25 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=simple/simple; d=auckland.ac.nz; i=@auckland.ac.nz; q=dns/txt; s=mail; t=1471611806; x=1503147806; h=from:to:subject:date:message-id:references:in-reply-to: content-transfer-encoding:mime-version; bh=OqNRTJiRlWK5umguvW+HI6NGSWXFdWLFjJX7Wn4iks4=; b=3gpXETrFneHPgKNfRYX85wtMiJH0GrcPhLqK2OkLkfUuP9L4jvCrl5PM 4imoJmnz/5KAVflfRbVXYkmEQwEDnwzAasTQRLZQIXACYmyVeeewMIFFC Cz1Jez32zmYCXCf6DAw9gc0e34/A/CtDhUxEeuJX8CtvmAjjmXHAsRPN0 HlM86JcdEc0P51CaZEqWnjvZbRzk0g0+QX64mKrONUcRrITGGpmGxQm+i 7bRTPCCJjnBmBpAcJPDUaEJ4RurgOLWXGdJ/ufm70xiGtAqvRp1GLVMe3 coK+TGgi6DfEbC8tyfWNUzLRCUD2m28Bd0kkQyQSiOao9aSWmNawXVCVN g==; X-IronPort-AV: E=Sophos;i="5.28,544,1464609600"; d="scan'208";a="102836537" X-Ironport-HAT: MAIL-SERVERS - $RELAYED X-Ironport-Source: 130.216.4.125 - Outgoing - Outgoing Received: from uxchange10-fe3.uoa.auckland.ac.nz ([130.216.4.125]) by mx4-int.auckland.ac.nz with ESMTP/TLS/AES256-SHA; 20 Aug 2016 01:03:23 +1200 Received: from UXCN10-5.UoA.auckland.ac.nz ([169.254.5.93]) by uxchange10-fe3.UoA.auckland.ac.nz ([169.254.143.234]) with mapi id 14.03.0266.001; Sat, 20 Aug 2016 01:03:23 +1200 From: Peter Gutmann To: Ilari Liusvaara , "tls@ietf.org" Thread-Topic: [TLS] RFC 7919 on Negotiated Finite Field Diffie-Hellman Ephemeral Parameters for Transport Layer Security (TLS) Thread-Index: AdH3qzVttHomztzDTIKlIRH23NqfIv//fPYAgAIjA03//486AIADpKzA//8+4gCAAMrJdg== Date: Fri, 19 Aug 2016 13:03:22 +0000 Message-ID: <9A043F3CF02CD34C8E74AC1594475C73F4CF421E@uxcn10-5.UoA.auckland.ac.nz> References: <9A043F3CF02CD34C8E74AC1594475C73F4CF009C@uxcn10-5.UoA.auckland.ac.nz> <20160816145548.GQ4670@mournblade.imrryr.org> <9A043F3CF02CD34C8E74AC1594475C73F4CF1AC9@uxcn10-5.UoA.auckland.ac.nz> <9A043F3CF02CD34C8E74AC1594475C73F4CF416C@uxcn10-5.UoA.auckland.ac.nz>, <20160819125658.v6t4d6stpo6tk476@LK-Perkele-V2.elisa-laajakaista.fi> In-Reply-To: <20160819125658.v6t4d6stpo6tk476@LK-Perkele-V2.elisa-laajakaista.fi> Accept-Language: en-NZ, en-GB, en-US Content-Language: en-NZ X-MS-Has-Attach: X-MS-TNEF-Correlator: x-originating-ip: [10.6.3.2] Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: quoted-printable MIME-Version: 1.0 Archived-At: Subject: Re: [TLS] RFC 7919 on Negotiated Finite Field Diffie-Hellman Ephemeral Parameters for Transport Layer Security (TLS) 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." List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Fri, 19 Aug 2016 13:03:28 -0000 Ilari Liusvaara writes:=0A= =0A= >AFAIK, that failure can only happen if at least one of:=0A= =0A= [...]=0A= =0A= New groups are introduced but the server or client only support the old one= s.=0A= So the server does ffdhe2048, the client does ffdhe2048', both are quite ha= ppy=0A= to do DHE-2048 but as a result of complying with 7919 they're forced to use= =0A= RSA.=0A= =0A= Peter.=