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

Ilari Liusvaara <ilariliusvaara@welho.com> Tue, 15 March 2016 07:50 UTC

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Date: Tue, 15 Mar 2016 09:50:40 +0200
From: Ilari Liusvaara <ilariliusvaara@welho.com>
To: Eric Rescorla <ekr@rtfm.com>
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Cc: Scott Schmit <i.grok@comcast.net>, "tls@ietf.org" <tls@ietf.org>
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.

Agreed. If the server maintains replay cache, one gets replay limited to
one per 0RTT connection even with DH-0RTT. And without server replay
cache, one gets near-infinite replay per 0RTT connection, no matter
what client does (other than 0*$VERYLARGE=0).



-Ilari