Re: [rtcweb] URI schemes for TURN and STUN

Eric Rescorla <ekr@rtfm.com> Thu, 03 November 2011 19:05 UTC

Return-Path: <ekr@rtfm.com>
X-Original-To: rtcweb@ietfa.amsl.com
Delivered-To: rtcweb@ietfa.amsl.com
Received: from localhost (localhost [127.0.0.1]) by ietfa.amsl.com (Postfix) with ESMTP id 148981F0CC9; Thu, 3 Nov 2011 12:05:17 -0700 (PDT)
X-Virus-Scanned: amavisd-new at amsl.com
X-Spam-Flag: NO
X-Spam-Score: -102.977
X-Spam-Level:
X-Spam-Status: No, score=-102.977 tagged_above=-999 required=5 tests=[BAYES_00=-2.599, FM_FORGED_GMAIL=0.622, RCVD_IN_DNSWL_LOW=-1, 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 YaurtazNu9Y6; Thu, 3 Nov 2011 12:05:16 -0700 (PDT)
Received: from mail-yw0-f44.google.com (mail-yw0-f44.google.com [209.85.213.44]) by ietfa.amsl.com (Postfix) with ESMTP id 6BAD31F0CC6; Thu, 3 Nov 2011 12:05:16 -0700 (PDT)
Received: by mail-yw0-f44.google.com with SMTP id 2so1894100ywt.31 for <multiple recipients>; Thu, 03 Nov 2011 12:05:16 -0700 (PDT)
Received: by 10.100.5.19 with SMTP id 19mr2513483ane.60.1320347110925; Thu, 03 Nov 2011 12:05:10 -0700 (PDT)
MIME-Version: 1.0
Received: by 10.146.232.12 with HTTP; Thu, 3 Nov 2011 11:54:13 -0700 (PDT)
X-Originating-IP: [74.95.2.173]
In-Reply-To: <8E6C5B0D-2161-4D14-9BEE-7B41998CDB7E@network-heretics.com>
References: <4EAC6BF4.2000604@alvestrand.no> <CALiegf=f4kFzyDLWK+Y5vbuCEJFXX590+VuZ4bbnHZnvX0CoBA@mail.gmail.com> <4EAC8AE0.3020307@acm.org> <4EACD558.1050003@alvestrand.no> <8E6C5B0D-2161-4D14-9BEE-7B41998CDB7E@network-heretics.com>
From: Eric Rescorla <ekr@rtfm.com>
Date: Thu, 03 Nov 2011 11:54:13 -0700
Message-ID: <CABcZeBNhHpyt5B03v9z1UJjs=WfeanoT82cBEf-VNdZtKerc0A@mail.gmail.com>
To: Keith Moore <moore@network-heretics.com>
Content-Type: text/plain; charset="ISO-8859-1"
Content-Transfer-Encoding: quoted-printable
Cc: Keith Moore <moore@cs.utk.edu>, Ned Freed <ned.freed@mrochek.com>, Behave WG <behave@ietf.org>, "rtcweb@ietf.org" <rtcweb@ietf.org>
Subject: Re: [rtcweb] URI schemes for TURN and STUN
X-BeenThere: rtcweb@ietf.org
X-Mailman-Version: 2.1.12
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: Thu, 03 Nov 2011 19:05:17 -0000

On Sat, Oct 29, 2011 at 9:44 PM, Keith Moore <moore@network-heretics.com> wrote:
>
> On Oct 30, 2011, at 12:40 AM, Harald Alvestrand wrote:
>
>> On 10/29/2011 04:23 PM, Marc Petit-Huguenin wrote:
>>> -----BEGIN PGP SIGNED MESSAGE-----
>>> Hash: SHA1
>>>
>>> On 10/29/2011 03:36 PM, Iñaki Baz Castillo wrote:
>>>> 2011/10/29 Harald Alvestrand<harald@alvestrand.no>:
>>>>> - I do not think it's appropriate to use "turn" and "turns" for indicating
>>>>> transport. Polluting the URI namespace with more configuration parameters in
>>>>> the form of trailing "s" is a Bad Thing.
>>>> But there should be some way to indicate that a TURN server listens in
>>>> TLS, right?
>>>>
>>> We should continue this discussion in BEHAVE, but I would like to ask the OP to
>>> send a pointer on the RFC or discussion that says that using a trailing "s" to
>>> indicate security is a bad thing.
>> I'll have to forward this question to the apps ADs of a few years ago about whether there's documentation for it. It does not seem to have been captured in an RFC that I can find; discussion was in the ~2000-2005 timeframe.
>>
>> The short version, from memory: Doing "s" locks you into one and exactly one security scheme, and prevents you from saying anything about the requisite parameters for that scheme, while using AUTH parameters such as POP or in-band negotiation such as IMAP  are much more flexible approaches.
>
> Security schemes change over time as new (presumably better) ones appear, and vulnerabilities are discovered in old ones.   There's nothing inherently wrong with having a URI scheme end in "s".  But it's a Bad Idea to promote the notion that "s" means "security".

What the "s" means is "Connect via TLS and check the server cert".
People are free to infer
whatever they want about the level of "security" provided.

-Ekr