Re: [TLS] Security review of TLS1.3 0-RTT

Benjamin Kaduk <bkaduk@akamai.com> Tue, 02 May 2017 18:43 UTC

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To: Nico Williams <nico@cryptonector.com>
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Cc: TLS WG <tls@ietf.org>
From: Benjamin Kaduk <bkaduk@akamai.com>
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Date: Tue, 02 May 2017 13:39:59 -0500
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Subject: Re: [TLS] Security review of TLS1.3 0-RTT
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On 05/02/2017 01:25 PM, Nico Williams wrote:
> If it's at all possible to move this timestamp into an authenticator at
> this point, I think that's the best solution.

I thought TLS clients were supposed to have even worse clocks (in terms
of absolute time) than Kerberos clients.  The current ticket_age scheme
only requires the client's clock *rate* to be reasonable, not its
absolute time.

-Ben