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

Paul Wouters <paul@xelerance.com> Wed, 03 August 2011 03:59 UTC

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Date: Wed, 3 Aug 2011 00:01:02 -0400 (EDT)
From: Paul Wouters <paul@xelerance.com>
To: Martin Rex <mrex@sap.com>
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Cc: tls@ietf.org
Subject: Re: [TLS] Review of draft-wouters-tls-oob-pubkey-00.txt
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On Tue, 2 Aug 2011, Martin Rex wrote:

> I find the idea of extending rfc6091 with a new certificate type
> for raw keys more appealing that a completely new TLS extension.

The TLS client still needs a way to convey this to the server, so that
there is a migration path from full CA bundle to public key. That is,
the client needs to be able to ask for "public key only" certificate type.
So I believe we would still need a new TLS extension, but not a new TLS
message type.

> I also prefer the server key to part of the full TLS handshake, so that
> the situation "client doesn't trust server key" or "client expected
> different server key" can be reliably distinguished from other reasons
> of a Finished message verification failure.

I see no problems with that.

Paul