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

Martin Thomson <martin.thomson@gmail.com> Mon, 23 March 2015 15:18 UTC

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Date: Mon, 23 Mar 2015 08:18:14 -0700
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From: Martin Thomson <martin.thomson@gmail.com>
To: Brian Sniffen <bsniffen@akamai.com>
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Subject: Re: [TLS] 0-RTT and Anti-Replay
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On 23 March 2015 at 08:00, Brian Sniffen <bsniffen@akamai.com>; wrote:
> APIs offering a socket model and attempting to provide a secure socket
> layer shouldn't use the 0RTT path at all, then?  APIs exposing a record
> or message semantics (either TLS's, or their own) can use 0RTT iff they
> can guarantee idempotency of the messages in the 0RTT fragment

That sounds like a reasonable first approximation.  It might be that a
streamed/socket protocol can intrinsically handle the replay problem
because of the nature of the protocol, but in the generic sense, this
would be correct.