Re: [radext] Review of draft-winter-radext-populating-eapidentity-01

Bernard Aboba <bernard_aboba@hotmail.com> Mon, 20 July 2015 12:20 UTC

Return-Path: <bernard_aboba@hotmail.com>
X-Original-To: radext@ietfa.amsl.com
Delivered-To: radext@ietfa.amsl.com
Received: from localhost (ietfa.amsl.com [127.0.0.1]) by ietfa.amsl.com (Postfix) with ESMTP id E9ADB1A21B4 for <radext@ietfa.amsl.com>; Mon, 20 Jul 2015 05:20:39 -0700 (PDT)
X-Virus-Scanned: amavisd-new at amsl.com
X-Spam-Flag: NO
X-Spam-Score: -2.61
X-Spam-Level:
X-Spam-Status: No, score=-2.61 tagged_above=-999 required=5 tests=[BAYES_00=-1.9, FREEMAIL_FROM=0.001, RCVD_IN_DNSWL_LOW=-0.7, SPF_PASS=-0.001, T_RP_MATCHES_RCVD=-0.01] autolearn=ham
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 SItj5urhNj0M for <radext@ietfa.amsl.com>; Mon, 20 Jul 2015 05:20:37 -0700 (PDT)
Received: from BLU004-OMC1S3.hotmail.com (blu004-omc1s3.hotmail.com [65.55.116.14]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-SHA384 (256/256 bits)) (No client certificate requested) by ietfa.amsl.com (Postfix) with ESMTPS id E87781A21AE for <radext@ietf.org>; Mon, 20 Jul 2015 05:20:36 -0700 (PDT)
Received: from BLU406-EAS92 ([65.55.116.7]) by BLU004-OMC1S3.hotmail.com over TLS secured channel with Microsoft SMTPSVC(7.5.7601.23008); Mon, 20 Jul 2015 05:20:35 -0700
X-TMN: [clXIBPCQF2UGPMO6x9iuK9s4/B7mpzLE]
X-Originating-Email: [bernard_aboba@hotmail.com]
Message-ID: <BLU406-EAS922E8820069F5C62F8D5E193850@phx.gbl>
Content-Type: text/plain; charset="utf-8"
Content-Transfer-Encoding: base64
From: Bernard Aboba <bernard_aboba@hotmail.com>
MIME-Version: 1.0 (1.0)
Date: Mon, 20 Jul 2015 14:16:31 +0200
References: <11856_1427820628_551AD054_11856_4576_1_6B7134B31289DC4FAF731D844122B36EEF6888@PEXCVZYM13.corporate.adroot.infra.ftgroup> <tsllhid84gm.fsf@mit.edu> <BLU181-W6B49664DD504DDAF5CC9F93F40@phx.gbl> <30317_1427824394_551ADF0A_30317_14370_1_6B7134B31289DC4FAF731D844122B36EEF74CD@PEXCVZYM13.corporate.adroot.infra.ftgroup> <BLU181-W86B005505E6468F75180593F40@phx.gbl> <tsl4mp182ku.fsf@mit.edu> <BA6CBD09-148F-4F8C-9B81-8A4A88B64287@deployingradius.com> <BLU406-EAS343D630A63D85F897C0EC8793F40@phx.gbl> <14078_1427880628_551BBAB4_14078_5155_1_6B7134B31289DC4FAF731D844122B36EF0B91F@PEXCVZYM13.corporate.adroot.infra.ftgroup> <190D3355-0BB7-48D5-BEA2-55773E9BD785@deployingradius.com> <24001_1437383629_55ACBBCD_24001_3716_1_6B7134B31289DC4FAF731D844122B36E01CC9ED3@OPEXCLILM43.corporate.adroot.infra.ftgroup> <BLU181-W94C6FC52C2E3CD666F631A93850@phx.gbl> <tslzj2r5aoj.fsf@mit.edu> <6155_1437393977_55ACE439_6155_10573_1_6B7134B31289DC4FAF731D844122B36E01CCA3D4@OPEXCLILM43.corporate.adroot.infra.ftgroup>
To: "lionel.morand@orange.com" <lionel.morand@orange.com>
In-Reply-To: <6155_1437393977_55ACE439_6155_10573_1_6B7134B31289DC4FAF731D844122B36E01CCA3D4@OPEXCLILM43.corporate.adroot.infra.ftgroup>
X-OriginalArrivalTime: 20 Jul 2015 12:20:35.0742 (UTC) FILETIME=[7B1BA3E0:01D0C2E6]
Archived-At: <http://mailarchive.ietf.org/arch/msg/radext/MQz2h58gs1yuIaQ4FD1QFnDP6V8>
Cc: Sam Hartman <hartmans@painless-security.com>, "radext@ietf.org" <radext@ietf.org>
Subject: Re: [radext] Review of draft-winter-radext-populating-eapidentity-01
X-BeenThere: radext@ietf.org
X-Mailman-Version: 2.1.15
Precedence: list
List-Id: RADIUS EXTensions working group discussion list <radext.ietf.org>
List-Unsubscribe: <https://www.ietf.org/mailman/options/radext>, <mailto:radext-request@ietf.org?subject=unsubscribe>
List-Archive: <https://mailarchive.ietf.org/arch/browse/radext/>
List-Post: <mailto:radext@ietf.org>
List-Help: <mailto:radext-request@ietf.org?subject=help>
List-Subscribe: <https://www.ietf.org/mailman/listinfo/radext>, <mailto:radext-request@ietf.org?subject=subscribe>
X-List-Received-Date: Mon, 20 Jul 2015 12:20:40 -0000

The point is that the document's recommendations are based on using method specific identities to determine the EAP-Response/Identity. This is fundamentally broken because those identities are unrelated and the two identities  need not use the same formats or encodings - and as a result the advice based on this incorrect assumption would result in authentication failures, unacceptable delays and worse.

The document itself points this out - but does not recognize that the problem itself results from a false assumption.


> On Jul 20, 2015, at 14:06, lionel.morand@orange.com wrote:
> 
> Hi Bernard,
> 
> I tend to agree with Sam. I will review again the draft based on your comment. However I understand that the point is WHEN "Identity Response be used primarily for routing purposes ", there is some considerations to take into account to use it as user-name identity in RADIUS and Diameter. Everything else related to method-specific EAP identity (format, use, etc.) is out of scope of this document. At least it is my current understanding.
> 
> Lionel
> 
> -----Message d'origine-----
> De : radext [mailto:radext-bounces@ietf.org] De la part de Sam Hartman
> Envoyé : lundi 20 juillet 2015 13:30
> À : Bernard Aboba
> Cc : radext@ietf.org
> Objet : Re: [radext] Review of draft-winter-radext-populating-eapidentity-01
> 
>>>>>> "Bernard" == Bernard Aboba <bernard_aboba@hotmail.com> writes:
> 
>    Bernard>    One of the fundamental assumptions of this document is
>    Bernard> that the EAP-Response/Identity is somehow determined from
>    Bernard> the method-specific identities.  This is not correct, as
>    Bernard> RFC 3748 Section 5.1 makes clear:
> 
> Hi.  I was very confused to read this paragraph, because we've discussed this issue several times and I think we're all in agreement that the method-specific identities are not directly related to the eap response/identity.  I think that as the text you cite from RFC 3748 points out, the EAP response is often used for routing, so in many deployments there is some relation.
> 
> I stopped reading your review after this first paragraph, because I think that this disconnect colors the entire review.  I'd really appreciate it if you would explain why you think the document is assuming that the eap-response/identity is determined from method identities.
> I know that was not our intent.
> 
> I do think it's true that implementations sometimes derive both the eap response/identity and the method-specific identities from a common principal.
> Other implementations request both identities from the user.
> However, I don't know anything that tries to map back from a method identity to an eap response.
> 
> --Sam
> 
> _______________________________________________
> radext mailing list
> radext@ietf.org
> https://www.ietf.org/mailman/listinfo/radext
> 
> _________________________________________________________________________________________________________________________
> 
> Ce message et ses pieces jointes peuvent contenir des informations confidentielles ou privilegiees et ne doivent donc
> pas etre diffuses, exploites ou copies sans autorisation. Si vous avez recu ce message par erreur, veuillez le signaler
> a l'expediteur et le detruire ainsi que les pieces jointes. Les messages electroniques etant susceptibles d'alteration,
> Orange decline toute responsabilite si ce message a ete altere, deforme ou falsifie. Merci.
> 
> This message and its attachments may contain confidential or privileged information that may be protected by law;
> they should not be distributed, used or copied without authorisation.
> If you have received this email in error, please notify the sender and delete this message and its attachments.
> As emails may be altered, Orange is not liable for messages that have been modified, changed or falsified.
> Thank you.
>