Re: [mpls] [secdir] Secdir last call review of draft-ietf-mpls-lsp-ping-lag-multipath-05

Mach Chen <mach.chen@huawei.com> Thu, 14 February 2019 03:02 UTC

Return-Path: <mach.chen@huawei.com>
X-Original-To: mpls@ietfa.amsl.com
Delivered-To: mpls@ietfa.amsl.com
Received: from localhost (localhost [127.0.0.1]) by ietfa.amsl.com (Postfix) with ESMTP id B9914130EDD; Wed, 13 Feb 2019 19:02:22 -0800 (PST)
X-Virus-Scanned: amavisd-new at amsl.com
X-Spam-Flag: NO
X-Spam-Score: -4.2
X-Spam-Level:
X-Spam-Status: No, score=-4.2 tagged_above=-999 required=5 tests=[BAYES_00=-1.9, RCVD_IN_DNSWL_MED=-2.3, SPF_PASS=-0.001, URIBL_BLOCKED=0.001] 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 qcnKyaDyHFfo; Wed, 13 Feb 2019 19:02:20 -0800 (PST)
Received: from huawei.com (lhrrgout.huawei.com [185.176.76.210]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by ietfa.amsl.com (Postfix) with ESMTPS id A6B04130ECF; Wed, 13 Feb 2019 19:02:20 -0800 (PST)
Received: from lhreml706-cah.china.huawei.com (unknown [172.18.7.108]) by Forcepoint Email with ESMTP id 1F7D2A9FCB1644FFFE23; Thu, 14 Feb 2019 03:02:18 +0000 (GMT)
Received: from DGGEML405-HUB.china.huawei.com (10.3.17.49) by lhreml706-cah.china.huawei.com (10.201.108.47) with Microsoft SMTP Server (TLS) id 14.3.408.0; Thu, 14 Feb 2019 03:02:17 +0000
Received: from DGGEML510-MBX.china.huawei.com ([169.254.2.6]) by dggeml405-hub.china.huawei.com ([10.3.17.49]) with mapi id 14.03.0415.000; Thu, 14 Feb 2019 11:02:08 +0800
From: Mach Chen <mach.chen@huawei.com>
To: Benjamin Kaduk <kaduk@mit.edu>
CC: Linda Dunbar <linda.dunbar@huawei.com>, "secdir@ietf.org" <secdir@ietf.org>, "mpls@ietf.org" <mpls@ietf.org>, "draft-ietf-mpls-lsp-ping-lag-multipath.all@ietf.org" <draft-ietf-mpls-lsp-ping-lag-multipath.all@ietf.org>, "ietf@ietf.org" <ietf@ietf.org>
Thread-Topic: [secdir] Secdir last call review of draft-ietf-mpls-lsp-ping-lag-multipath-05
Thread-Index: AQHUkY+Xr7eIQ7lWe0az4uRG6fBCdqV9d+SwgERX9oCAHShNQA==
Date: Thu, 14 Feb 2019 03:02:07 +0000
Message-ID: <F73A3CB31E8BE34FA1BBE3C8F0CB2AE292889888@dggeml510-mbx.china.huawei.com>
References: <154455986336.13151.8483284555885294015@ietfa.amsl.com> <F73A3CB31E8BE34FA1BBE3C8F0CB2AE2927B2883@dggeml510-mbx.china.huawei.com> <20190126211729.GJ49072@kduck.mit.edu>
In-Reply-To: <20190126211729.GJ49072@kduck.mit.edu>
Accept-Language: en-US, zh-CN
Content-Language: zh-CN
X-MS-Has-Attach:
X-MS-TNEF-Correlator:
x-originating-ip: [10.111.194.201]
Content-Type: text/plain; charset="us-ascii"
Content-Transfer-Encoding: quoted-printable
MIME-Version: 1.0
X-CFilter-Loop: Reflected
Archived-At: <https://mailarchive.ietf.org/arch/msg/mpls/fYuuheHxRAUzQ2xVjc16Y9HqbcQ>
Subject: Re: [mpls] [secdir] Secdir last call review of draft-ietf-mpls-lsp-ping-lag-multipath-05
X-BeenThere: mpls@ietf.org
X-Mailman-Version: 2.1.29
Precedence: list
List-Id: Multi-Protocol Label Switching WG <mpls.ietf.org>
List-Unsubscribe: <https://www.ietf.org/mailman/options/mpls>, <mailto:mpls-request@ietf.org?subject=unsubscribe>
List-Archive: <https://mailarchive.ietf.org/arch/browse/mpls/>
List-Post: <mailto:mpls@ietf.org>
List-Help: <mailto:mpls-request@ietf.org?subject=help>
List-Subscribe: <https://www.ietf.org/mailman/listinfo/mpls>, <mailto:mpls-request@ietf.org?subject=subscribe>
X-List-Received-Date: Thu, 14 Feb 2019 03:02:23 -0000

Hi Benjamin,

Sorry for the delayed response!

Please see my response inline...

> -----Original Message-----
> From: Benjamin Kaduk [mailto:kaduk@mit.edu]
> Sent: Sunday, January 27, 2019 5:17 AM
> To: Mach Chen <mach.chen@huawei.com>
> Cc: Linda Dunbar <linda.dunbar@huawei.com>; secdir@ietf.org;
> mpls@ietf.org; draft-ietf-mpls-lsp-ping-lag-multipath.all@ietf.org;
> ietf@ietf.org
> Subject: Re: [secdir] Secdir last call review of draft-ietf-mpls-lsp-ping-lag-
> multipath-05
> 
> On Fri, Dec 14, 2018 at 02:11:21AM +0000, Mach Chen wrote:
> > Hi Linda,
> >
> > Thanks for the review!
> >
> > Some responses inline...
> >
> > > -----Original Message-----
> > > From: ietf [mailto:ietf-bounces@ietf.org] On Behalf Of Linda Dunbar
> > > Sent: Wednesday, December 12, 2018 4:24 AM
> > > To: secdir@ietf.org
> > > Cc: mpls@ietf.org;
> > > draft-ietf-mpls-lsp-ping-lag-multipath.all@ietf.org;
> > > ietf@ietf.org
> > > Subject: Secdir last call review of
> > > draft-ietf-mpls-lsp-ping-lag-multipath-05
> > >
> > > Reviewer: Linda Dunbar
> > > Review result: Ready
> > >
> > > I have reviewed this document as part of the security directorate's
> > > ongoing effort to review all IETF documents being processed by the
> > > IESG.  These comments were written primarily for the benefit of the
> > > security area directors.  Document editors and WG chairs should
> > > treat these comments just like any other last call comments.
> > >
> > > The summary of the review is Ready with comment
> > >
> > > The described mechanism for LSP Multipath Ping is very clear. The
> > > Security Consideration re-uses the description of RFC8029, which is
> > > very comprehensive.
> > > It would be better if the draft describes how to prevent
> > > intermediate LSRs in between the Initiating LSR and Responding LSR
> > > from mis-using the detailed link information (e.g. forwarding to
> somewhere else).
> >
> > The Echo Request and Reply messages are directly exchanged between the
> Initiating LSR and the Responding LSR, those intermediate LSRs just forward
> the messages as normal packets, they will not see the detailed link
> information unless if they inspect and do DPI on every packet forwarded by
> them.
> >
> > The detailed link information is supplied to the Initiating LSR for using, the
> intermediate LSRs will not try to use it even if they received the information,
> because there is no corresponding Echo Request to the received Echo Reply.
> 
> The intermediate LSRs still will have access to the plaintext information, even
> if in normal operation they do not need to act upon that information.
> Generally in this sort of situation we will either explicitly state that the
> intermediate nodes must be trusted to not abuse the information in
> question, or provide some mechanism for end-to-end confidentiality
> protection.

"Intermediate nodes must be trusted to not abuse the information" is normally assumed. For the intermediate nodes, there is no different between the Echo Reply messages and any other data traffic, control messages. They just forward the Echo Reply messages as normal packets.  I am not sure it needs to explicitly state this.  Do you suggest to add such a statement in the security consideration section?

> 
> Also (noting that I only skimmed the document so this may not make sense),
> the security considerations seem to suggest using an IP ACL for determining
> which messages are trusted; IP ACLs are generally not recommended in favor
> of cryptographic mechanisms at this point.

IP ACLs was introduced in RFC 8029 and is reused in this document, it's just one of the security mechanisms. This document is an extension to  RFC 8029, as stated in this document, all security considerations defined in RFC 8029 apply to this document. Do you have any specific suggestion to the current security consideration?

Best regards,
Mach
> 
> -Benjamin