Re: [TLS] New draft: draft-solinas-tls-additional-prf-input-00.txt

Russ Housley <housley@vigilsec.com> Mon, 26 October 2009 18:41 UTC

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Date: Mon, 26 Oct 2009 14:41:43 -0400
To: Pasi.Eronen@nokia.com
From: Russ Housley <housley@vigilsec.com>
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Subject: Re: [TLS] New draft: draft-solinas-tls-additional-prf-input-00.txt
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Pasi:

>I'd like to re-iterate my earlier concern about the original
>draft-rescorla-tls-opaque-prf-input draft: this defines a basically
>general-purpose extension mechanism to TLS.
>
>We already have a well-defined extension mechanism for TLS (TLS
>extensions), which would allow people to do exactly the sorts of
>things envisioned in Section 1.1. Its only "drawback" is that it
>requires going through the IETF process to obtain the IANA allocation,
>and thus publicly documenting what you're doing.

I do not think this is a fair characterization.  TLS extensions 
cannot provide additional PRF inputs.  To my eyes, that is the 
fundamental difference here.

Russ
(also with no hats on)