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Re: [TLS] Consensus Call on Removing GMT from the Handshake

Martin Thomson <martin.thomson@gmail.com> Sat, 14 June 2014 00:16 UTC

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Date: Fri, 13 Jun 2014 17:16:53 -0700
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From: Martin Thomson <martin.thomson@gmail.com>
To: "Joseph Salowey (jsalowey)" <jsalowey@cisco.com>
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Subject: Re: [TLS] Consensus Call on Removing GMT from the Handshake
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On 13 June 2014 16:11, Joseph Salowey (jsalowey) <jsalowey@cisco.com> wrote:
> - Should we remove the GMT values from the client and server values in TLS 1.3?

I'd prefer to see it removed.

> - Should we remove the GMT fields from the current versions of TLS and adopt
> draft-mathewson-no-gmtunixtime-00 or something similar?

I think that this statement:

   ... TLS implementors
   MUST by default set the entire value the ClientHello.Random and
   ServerHello.Random fields, including gmt_unix_time, to a
   cryptographically random sequence.

Is enough.  The rationale is a little overblown.

That should help expose more of the RNG state ;)

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