Subject: [TLS] OCSP status_request_v2 extension

From: Hubert Kario <[email-masked]>
Date: Mon, 14 Aug 2017 20:03:08 +0200

Current (21) draft references RFC 6961 in multiple places, in particular
 * Section 4.4.2:
     Valid extensions
     include OCSP Status extensions ([RFC6066] and [RFC6961])
 * and therein implicitly:
     If
     an extension applies to the entire chain, it SHOULD be included in
     the first CertificateEntry.

at the same time section B.3.1 ExtensionType and table from Section 4.2 do not 
list status_request_v2 as a valid extension.

If the intention was to deprecate status_request_v2, I think the references to 
RFC 6961 should be a bit more cautious. If it wasn't (as old messages sent to 
the list would indicate), quite a bit of text is missing.
-- 
Regards,
Hubert Kario
Senior Quality Engineer, QE BaseOS Security team
Web: www.cz.redhat.com
Red Hat Czech s.r.o., Purkyňova 115, 612 00  Brno, Czech Republic

---

From: Ilari Liusvaara <[email-masked]>
Date: Mon, 14 Aug 2017 21:26:16 +0300

> the list would indicate), quite a bit of text is missing.

The introduction suggests that TLS 1.3 intends to deprecate
status_request_v2.

And indeed, if status_request_v2 was to be supported, extra text would
be required. Like how to map the list of certificates inside the
message to certificates sent.

I think that clause about extensions to whole chain are more for things
like server_certificate_type.

Furthermore, in WebPKI, CA certificate OCSP is at best useless due to
the very long response lifetimes. And getting the liftimes down to
reasonable range is not realistic.

-Ilari

---

From: Benjamin Kaduk <[email-masked]>
Date: Tue, 15 Aug 2017 12:42:30 -0500

> The introduction suggests that TLS 1.3 intends to deprecate

Yes, the intention was to deprecate status_request_v2.

-Ben

---

From: Hubert Kario <[email-masked]>
Date: Wed, 16 Aug 2017 13:54:52 +0200

On Tuesday, 15 August 2017 19:42:30 CEST Benjamin Kaduk wrote:
> >> at the same time section B.3.1 ExtensionType and table from Section 4.2
> >> do not list status_request_v2 as a valid extension.
> >> 
> >> 
> >> If the intention was to deprecate status_request_v2, I think the
> >> references to RFC 6961 should be a bit more cautious. If it wasn't (as
> >> old messages sent to the list would indicate), quite a bit of text is
> >> missing.
> > 

Proposed text to remove the ambiguity:
https://github.com/tlswg/tls13-spec/pull/1075