[Ace] "default value" for authz-info endpoint

Benjamin Kaduk <kaduk@mit.edu> Sat, 30 May 2020 22:36 UTC

Return-Path: <kaduk@mit.edu>
X-Original-To: ace@ietfa.amsl.com
Delivered-To: ace@ietfa.amsl.com
Received: from localhost (localhost [127.0.0.1]) by ietfa.amsl.com (Postfix) with ESMTP id C34AD3A0B35 for <ace@ietfa.amsl.com>; Sat, 30 May 2020 15:36:10 -0700 (PDT)
X-Virus-Scanned: amavisd-new at amsl.com
X-Spam-Flag: NO
X-Spam-Score: -1.899
X-Spam-Level:
X-Spam-Status: No, score=-1.899 tagged_above=-999 required=5 tests=[BAYES_00=-1.9, SPF_HELO_NONE=0.001, 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 eC9hLue2eWhe for <ace@ietfa.amsl.com>; Sat, 30 May 2020 15:36:06 -0700 (PDT)
Received: from outgoing.mit.edu (outgoing-auth-1.mit.edu [18.9.28.11]) (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 9D56F3A0B34 for <ace@ietf.org>; Sat, 30 May 2020 15:36:06 -0700 (PDT)
Received: from kduck.mit.edu ([24.16.140.251]) (authenticated bits=56) (User authenticated as kaduk@ATHENA.MIT.EDU) by outgoing.mit.edu (8.14.7/8.12.4) with ESMTP id 04UMa2LL013733 (version=TLSv1/SSLv3 cipher=DHE-RSA-AES256-GCM-SHA384 bits=256 verify=NOT) for <ace@ietf.org>; Sat, 30 May 2020 18:36:04 -0400
Date: Sat, 30 May 2020 15:36:02 -0700
From: Benjamin Kaduk <kaduk@mit.edu>
To: ace@ietf.org
Message-ID: <20200530223602.GF58497@kduck.mit.edu>
MIME-Version: 1.0
Content-Type: text/plain; charset="us-ascii"
Content-Disposition: inline
User-Agent: Mutt/1.12.1 (2019-06-15)
Archived-At: <https://mailarchive.ietf.org/arch/msg/ace/mDT5I-SGrzmpKPDUX77xNA3W2OI>
Subject: [Ace] "default value" for authz-info endpoint
X-BeenThere: ace@ietf.org
X-Mailman-Version: 2.1.29
Precedence: list
List-Id: "Authentication and Authorization for Constrained Environments \(ace\)" <ace.ietf.org>
List-Unsubscribe: <https://www.ietf.org/mailman/options/ace>, <mailto:ace-request@ietf.org?subject=unsubscribe>
List-Archive: <https://mailarchive.ietf.org/arch/browse/ace/>
List-Post: <mailto:ace@ietf.org>
List-Help: <mailto:ace-request@ietf.org?subject=help>
List-Subscribe: <https://www.ietf.org/mailman/listinfo/ace>, <mailto:ace-request@ietf.org?subject=subscribe>
X-List-Received-Date: Sat, 30 May 2020 22:36:11 -0000

Hi all,

I was prompted by the discussion at the interim to look more closely at
what we say about the "default name" for endpoint URIs, e.g., the
authz-info endpoint.  The last paragraph of
https://tools.ietf.org/html/draft-ietf-ace-oauth-authz-33#section-5.8.1
says:

   The default name of this endpoint in an url-path is '/authz-info',
   however implementations are not required to use this name and can
   define their own instead.

I've gotten advice from some URI experts that this doesn't give an
easy/discoverable path (pun intended) to using a non-default value, which
is problematic from the perspective of BCP 190 (and we should expect to get
discussed at IESG evaluation time).  This sort of issue goes away if we
allocate a well-known URI for authz-info from
https://www.iana.org/assignments/well-known-uris/well-known-uris.xhtml and
have that be the default.  In particular, that wouldn't actually stop any
deployments from using /authz-info, but it does mean they'd have to
knowingly "opt in" to doing so.

What do people think?

Thanks,

Ben