Re: [TLS] Let's remove gmt_unix_time from TLS

Adam Langley <agl@google.com> Wed, 11 September 2013 16:13 UTC

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From: Adam Langley <agl@google.com>
Date: Wed, 11 Sep 2013 12:11:58 -0400
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To: Eric Rescorla <ekr@rtfm.com>
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Cc: perpass@ietf.org, "tls@ietf.org" <tls@ietf.org>, Alfredo Pironti <alfredo@pironti.eu>
Subject: Re: [TLS] Let's remove gmt_unix_time from TLS
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On Wed, Sep 11, 2013 at 12:06 PM, Eric Rescorla <ekr@rtfm.com> wrote:
> Before we discuss mechanisms, it would be good to verify that in general
> clients and servers don't become unhappy if the timestamp is radically
> wrong. Has someone done measurements to verify that this is in fact
> the case at a broad scale?

I've observed that some small fraction of traffic to Google puts
random bytes in the first-four bytes of the nonce. It was less than
1%, but some clients clearly do this already.


Cheers

AGL