Re: [TLS] Splitting all stateless 0RTT into its own document (was Re: analysis of wider impact of TLS1.3 replayabe data)

Viktor Dukhovni <ietf-dane@dukhovni.org> Tue, 15 March 2016 07:55 UTC

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Date: Tue, 15 Mar 2016 07:55:06 +0000
From: Viktor Dukhovni <ietf-dane@dukhovni.org>
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Subject: Re: [TLS] Splitting all stateless 0RTT into its own document (was Re: analysis of wider impact of TLS1.3 replayabe data)
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On Mon, Mar 14, 2016 at 12:32:51PM -0700, Eric Rescorla wrote:

> As far as I can tell, there's no protocol difference between "stateful" and
> "stateless" resumption.
> You use the same techniques (a replay cache) and the question is merely
> whether the server
> actually maintains one.

Experience with "replay caches" in Kerberos shows that they don't
work in the vast majority of cases.  Protocols need to be safe
without replay caches.

-- 
	Viktor.