Re: [rtcweb] Last Call: <draft-ietf-rtcweb-data-channel-12.txt> (WebRTC Data Channels) to Proposed Standard

Michael Tuexen <Michael.Tuexen@lurchi.franken.de> Sat, 11 October 2014 07:41 UTC

Return-Path: <Michael.Tuexen@lurchi.franken.de>
X-Original-To: rtcweb@ietfa.amsl.com
Delivered-To: rtcweb@ietfa.amsl.com
Received: from localhost (ietfa.amsl.com [127.0.0.1]) by ietfa.amsl.com (Postfix) with ESMTP id 770D01A0055 for <rtcweb@ietfa.amsl.com>; Sat, 11 Oct 2014 00:41:42 -0700 (PDT)
X-Virus-Scanned: amavisd-new at amsl.com
X-Spam-Flag: NO
X-Spam-Score: -2.337
X-Spam-Level:
X-Spam-Status: No, score=-2.337 tagged_above=-999 required=5 tests=[BAYES_00=-1.9, HELO_EQ_DE=0.35, RP_MATCHES_RCVD=-0.786, SPF_HELO_PASS=-0.001] 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 BGmnGRJ74VwA for <rtcweb@ietfa.amsl.com>; Sat, 11 Oct 2014 00:41:40 -0700 (PDT)
Received: from mail-n.franken.de (drew.ipv6.franken.de [IPv6:2001:638:a02:a001:20e:cff:fe4a:feaa]) (using TLSv1 with cipher ADH-AES256-SHA (256/256 bits)) (No client certificate requested) by ietfa.amsl.com (Postfix) with ESMTPS id E60D91A004B for <rtcweb@ietf.org>; Sat, 11 Oct 2014 00:41:39 -0700 (PDT)
Received: from [192.168.1.104] (p508F121A.dip0.t-ipconnect.de [80.143.18.26]) (Authenticated sender: macmic) by mail-n.franken.de (Postfix) with ESMTP id DA40A1C1050E0; Sat, 11 Oct 2014 09:41:36 +0200 (CEST)
Content-Type: text/plain; charset="us-ascii"
Mime-Version: 1.0 (Mac OS X Mail 7.3 \(1878.6\))
From: Michael Tuexen <Michael.Tuexen@lurchi.franken.de>
In-Reply-To: <03a3bbbc282b4e6d88d587931b46b5f8@CY1PR0501MB1579.namprd05.prod.outlook.com>
Date: Sat, 11 Oct 2014 09:41:35 +0200
Content-Transfer-Encoding: quoted-printable
Message-Id: <57B40110-2F21-4893-B77C-54F46D18567F@lurchi.franken.de>
References: <20141010004836.12666.88765.idtracker@ietfa.amsl.com> <91953101b2634ec69d14e120ea62d929@CY1PR0501MB1579.namprd05.prod.outlook.com> <CABkgnnWE7czWqi4vQRb5d50N2k95joc_Zcvw6w6g7SOjU9b+9g@mail.gmail.com> <03a3bbbc282b4e6d88d587931b46b5f8@CY1PR0501MB1579.namprd05.prod.outlook.com>
To: "Wyss, Felix" <Felix.Wyss@inin.com>
X-Mailer: Apple Mail (2.1878.6)
Archived-At: http://mailarchive.ietf.org/arch/msg/rtcweb/yanl33b_om_x-y9b8uyIGAZTdVw
Cc: "rtcweb@ietf.org" <rtcweb@ietf.org>
Subject: Re: [rtcweb] Last Call: <draft-ietf-rtcweb-data-channel-12.txt> (WebRTC Data Channels) to Proposed Standard
X-BeenThere: rtcweb@ietf.org
X-Mailman-Version: 2.1.15
Precedence: list
List-Id: Real-Time Communication in WEB-browsers working group list <rtcweb.ietf.org>
List-Unsubscribe: <https://www.ietf.org/mailman/options/rtcweb>, <mailto:rtcweb-request@ietf.org?subject=unsubscribe>
List-Archive: <http://www.ietf.org/mail-archive/web/rtcweb/>
List-Post: <mailto:rtcweb@ietf.org>
List-Help: <mailto:rtcweb-request@ietf.org?subject=help>
List-Subscribe: <https://www.ietf.org/mailman/listinfo/rtcweb>, <mailto:rtcweb-request@ietf.org?subject=subscribe>
X-List-Received-Date: Sat, 11 Oct 2014 07:41:42 -0000

On 11 Oct 2014, at 09:21, Wyss, Felix <Felix.Wyss@inin.com> wrote:

> I'm not looking at this in terms of MitM attacks but for topologies where we want to have back-to-back WebRTC sessions going through a legitimate middlebox.  That middlebox passes the media and data between these sessions while recording and/or performing analytics on it.  Requiring the 
So doesn't it terminate the DTLS connections of both peers?

Best regards
Michael
> middlebox to worry about how the two endpoints might pick SCTP stream identifiers and possibly having to map or rewrite them unnecessarily complicates their implementation.  
> 
> IMHO from the perspective of the data channels, the DTLS layer should be an opaque tunnel ("bump in the stack") that passes packets between endpoints.  The DTLS role of an endpoint that emerges during connection establishment should not be relevant to the operation of the data channels.  Hence my concerns about the abstraction leak.  
> 
> Thanks,
> --Felix
> 
>> -----Original Message-----
>> From: Martin Thomson [mailto:martin.thomson@gmail.com]
>> Sent: Friday, October 10, 2014 16:34
>> To: Wyss, Felix
>> Cc: rtcweb@ietf.org
>> Subject: Re: [rtcweb] Last Call: <draft-ietf-rtcweb-data-channel-12.txt>
>> (WebRTC Data Channels) to Proposed Standard
>> 
>> On 10 October 2014 12:11, Wyss, Felix <Felix.Wyss@inin.com> wrote:
>>> I feel it would be better to explicitly require that applications are
>> responsible for identifier collision avoidance instead of allowing them to rely
>> on the DTLS roles.
>> 
>> Are you suggesting that we might want to consider the effect of a MitM
>> attack on the robustness of this?
> _______________________________________________
> rtcweb mailing list
> rtcweb@ietf.org
> https://www.ietf.org/mailman/listinfo/rtcweb
>