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

Adam Langley <agl@imperialviolet.org> Sat, 14 June 2014 00:28 UTC

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From: Adam Langley <agl@imperialviolet.org>
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 Fri, Jun 13, 2014 at 4:11 PM, Joseph Salowey (jsalowey)
<jsalowey@cisco.com> wrote:
> - Should we remove the GMT values from the client and server values in TLS 1.3?

Yes, in the same way as below...

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

Yes, at the SHOULD level. For servers we have some clients that take a
clock-sync signal from the GMT time and we wouldn't immediately want
to break them.

For clients, there is basically no value and it leaks a fingerprint.
Additionally, this would be reflecting reality because implementations
are already doing this.


Cheers

AGL

-- 
Adam Langley agl@imperialviolet.org https://www.imperialviolet.org

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