Re: [MSEC] Review comments, was RE: GDOI support for IEC 62351

Brian Weis <bew@cisco.com> Mon, 21 October 2013 18:10 UTC

Return-Path: <bew@cisco.com>
X-Original-To: msec@ietfa.amsl.com
Delivered-To: msec@ietfa.amsl.com
Received: from localhost (localhost [127.0.0.1]) by ietfa.amsl.com (Postfix) with ESMTP id C3DA811E83C9 for <msec@ietfa.amsl.com>; Mon, 21 Oct 2013 11:10:41 -0700 (PDT)
X-Virus-Scanned: amavisd-new at amsl.com
X-Spam-Flag: NO
X-Spam-Score: -110.842
X-Spam-Level:
X-Spam-Status: No, score=-110.842 tagged_above=-999 required=5 tests=[AWL=-0.243, BAYES_00=-2.599, RCVD_IN_DNSWL_HI=-8, USER_IN_WHITELIST=-100]
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 XfO2jIF7bUKr for <msec@ietfa.amsl.com>; Mon, 21 Oct 2013 11:10:35 -0700 (PDT)
Received: from mtv-iport-3.cisco.com (mtv-iport-3.cisco.com [173.36.130.14]) by ietfa.amsl.com (Postfix) with ESMTP id 6F49511E8377 for <msec@ietf.org>; Mon, 21 Oct 2013 11:09:38 -0700 (PDT)
DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=cisco.com; i=@cisco.com; l=754; q=dns/txt; s=iport; t=1382378978; x=1383588578; h=mime-version:subject:from:in-reply-to:date:cc: content-transfer-encoding:message-id:references:to; bh=J5WKN6m1aaMFLNYe2cLYZNCW/1J0ECcIhzHIFOqnn7g=; b=I83uMNOe5Lu8fkDxm1WPRYziDNCdSagRy7Qrj6U+zcJf3PljV6DI54I2 Q0i67c969uMWYsMgSnu+dTQyQne6JkuypWacwtxp7Ne/uUPBijJeHkyM4 vAiDmlkVxPx/L9VgHhLj5ufCT1yBLKQGDqd24roNIDpo4O4NNZSlvIRGc U=;
X-IronPort-Anti-Spam-Filtered: true
X-IronPort-Anti-Spam-Result: AgAFAFhtZVKrRDoG/2dsb2JhbABWA4MHvzKBLhZ0giUBAQEDATo/EAtGVwYTiAAFAborjhKBFiMQBxGDDoEKA4k/jkqSB4NEgVE
X-IronPort-AV: E=Sophos;i="4.93,540,1378857600"; d="scan'208";a="92646898"
Received: from mtv-core-1.cisco.com ([171.68.58.6]) by mtv-iport-3.cisco.com with ESMTP; 21 Oct 2013 18:09:36 +0000
Received: from dhcp-128-107-147-33.cisco.com (dhcp-128-107-147-33.cisco.com [128.107.147.33]) by mtv-core-1.cisco.com (8.14.5/8.14.5) with ESMTP id r9LI9ZJV012003 (version=TLSv1/SSLv3 cipher=AES128-SHA bits=128 verify=NO); Mon, 21 Oct 2013 18:09:35 GMT
Content-Type: text/plain; charset=us-ascii
Mime-Version: 1.0 (Mac OS X Mail 6.6 \(1510\))
From: Brian Weis <bew@cisco.com>
In-Reply-To: <CE872AE6.2616B%paul@marvell.com>
Date: Mon, 21 Oct 2013 11:09:34 -0700
Content-Transfer-Encoding: quoted-printable
Message-Id: <1E12A57C-8EDE-45C4-871C-51AB24A8EAEE@cisco.com>
References: <CE872AE6.2616B%paul@marvell.com>
To: Paul Lambert <paul@marvell.com>
X-Mailer: Apple Mail (2.1510)
Cc: "msec@ietf.org" <msec@ietf.org>, Sean Turner <turners@ieca.com>, "draft-weis-gdoi-iec62351-9@tools.ietf.org" <draft-weis-gdoi-iec62351-9@tools.ietf.org>
Subject: Re: [MSEC] Review comments, was RE: GDOI support for IEC 62351
X-BeenThere: msec@ietf.org
X-Mailman-Version: 2.1.12
Precedence: list
List-Id: Multicast Security List <msec.ietf.org>
List-Unsubscribe: <https://www.ietf.org/mailman/options/msec>, <mailto:msec-request@ietf.org?subject=unsubscribe>
List-Archive: <http://www.ietf.org/mail-archive/web/msec>
List-Post: <mailto:msec@ietf.org>
List-Help: <mailto:msec-request@ietf.org?subject=help>
List-Subscribe: <https://www.ietf.org/mailman/listinfo/msec>, <mailto:msec-request@ietf.org?subject=subscribe>
X-List-Received-Date: Mon, 21 Oct 2013 18:10:42 -0000

Hi Paul,

On Oct 18, 2013, at 6:14 PM, Paul Lambert <paul@marvell.com>; wrote:

> 
>> 
>> We decided to drop support for AES-GCM here because there doesn't seem to
>> be a safe way to use AES-GCM in the GOOSE and SV security transforms.
>> AES-GCM takes a counter as input, but there is no explicit counter
>> defined in the IEC documents by which the receiver would know what
>> counter to use for decryption (or for integrity protection if AES-GMAC is
>> used).
> So what's used instead?

The draft specifies AES-CBC for confidentiality, and HMAC-SHA256 for integrity.

Brian

> 
> Paul
> 

-- 
Brian Weis
Security, Enterprise Networking Group, Cisco Systems
Telephone: +1 408 526 4796
Email: bew@cisco.com