Re: [TLS] Review of draft-wouters-tls-oob-pubkey-00.txt

Eric Rescorla <ekr@rtfm.com> Thu, 28 July 2011 13:20 UTC

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From: Eric Rescorla <ekr@rtfm.com>
Date: Thu, 28 Jul 2011 09:20:17 -0400
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To: Paul Wouters <paul@xelerance.com>
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Subject: Re: [TLS] Review of draft-wouters-tls-oob-pubkey-00.txt
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On Wed, Jul 27, 2011 at 8:18 PM, Paul Wouters <paul@xelerance.com>; wrote:
> On Wed, 27 Jul 2011, Eric Rescorla wrote:
>> Regardless, as I said in my review, this seems like it's largely
>> duplicative of cached info (and in fact, rather clumsier).
>
> I'm interested in knowing why you consider it "clumsy". Especially because
> it closely follows the RFC 6066 section 6 extension for supressing of
> sending CA bundles with "trusted_ca_keys".  That apparent clumsiness
> passed WGLC and IESG.

What's clumsy is:

(1) It's not generic, even though generic caching is useful.
(2) It doesn't support bare keys when the client doesn't know the key, which
is also useful, if you want to use bare keys at all. In fact, it
doesn't even appear
to support cases where the client knows only the key hash, which is common.

Whether it follows 6066 doesn't seem particularly relevant here, since we have a
worked example of something better.


-Ekr