Re: [TLS] Working Group Last Call for draft-ietf-tls-pwd

Eric Rescorla <> Thu, 05 December 2013 14:48 UTC

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From: Eric Rescorla <>
Date: Thu, 5 Dec 2013 06:47:52 -0800
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To: Bodo Moeller <>
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Subject: Re: [TLS] Working Group Last Call for draft-ietf-tls-pwd
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On Thu, Dec 5, 2013 at 3:48 AM, Bodo Moeller <> wrote:
> Dan Harkins <>rg>:
>> The exchange was reviewed by the CFRG with, as Joe noted, satisfactory
>> results.
> While it is true that Joe noted that, I think the point of the present
> discussion is that the protocol wasn't actually reviewed by the CFRG with
> satisfactory results.


The TLS WG isn't chartered to evaluate cryptographic mechanisms, so
where there is some question we generally rely on CFRG for an opinion
as we recently did with Salsa, ChaCha, etc. [1].  (I know you know
this, but to state for the mailing list)

With that in mind, TLS-PWD was the first time we did that and as Joe
stated, we did have a verbal report back from the chair of the CFRG
that they considered it satisfactory. However, based on the present
discussion it's clear that a number of people have concerns about
the security of the underlying mechanism. One of the purposes of
Last Call is to flush out exactly this kind of objection, so that's
good, though I wish we'd caught this earlier. We're still working
on the CFRG interface, so hopefully we'll get better at that part.

Anything we standardize in this area really does need to have a clean
report back from the CFRG. It seems clear that that's not the case

[As chair]