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

Nick Mathewson <nickm@torproject.org> Mon, 16 June 2014 14:25 UTC

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From: Nick Mathewson <nickm@torproject.org>
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Subject: Re: [TLS] Consensus Call on Removing GMT from the Handshake
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On Mon, Jun 16, 2014 at 4:28 AM, Robert Ransom <rransom.8774@gmail.com> wrote:
 [...]
> The more important (widely deployed) use of tlsdate is in Google's
> ChromeOS, which is probably why Adam Langley wants to not immediately
> turn off that timestamp field on Google's servers.  Since Google
> controls both the client software and the servers used for tlsdate in
> ChromeOS, their use of tlsdate should be completely safe.

For what it's worth, I believe that recent versions of tlsdate also
support learning the current time from an HTTPS "Date:" header, so
there's a plausible upgrade path there.

(Anybody who is interested in security and time should have a look
over at the NTP working group.  If I'm not mistaken, they've been
discussing an open draft that tries to improve the state of security
in NTP.)

cheers,
-- 
Nick Mathewson

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