Re: [TLS] 0-RTT and Anti-Replay

Martin Thomson <martin.thomson@gmail.com> Mon, 23 March 2015 14:42 UTC

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Date: Mon, 23 Mar 2015 07:42:50 -0700
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From: Martin Thomson <martin.thomson@gmail.com>
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Subject: Re: [TLS] 0-RTT and Anti-Replay
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On 23 March 2015 at 07:26, Colm MacCárthaigh <colm@allcosts.net>; wrote:
> I haven't been able to get my head around this. Doesn't that mean that
> an attacker can disable 0RTT for third parties at will?

To the extent that they can create connections that use 0RTT, yes.

And yes, narrowing the window means that clients need clocks that are
increasingly better synchronized to that of the server if they are to
succeed under these sorts of conditions.