Re: [TLS] analysis of wider impact of TLS1.3 replayabe data

Colm MacCárthaigh <colm@allcosts.net> Mon, 14 March 2016 18:29 UTC

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Date: Mon, 14 Mar 2016 11:29:19 -0700
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From: =?UTF-8?Q?Colm_MacC=C3=A1rthaigh?= <colm@allcosts.net>
To: Subodh Iyengar <subodh@fb.com>
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Subject: Re: [TLS] analysis of wider impact of TLS1.3 replayabe data
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On Mon, Mar 14, 2016 at 11:04 AM, Subodh Iyengar <subodh@fb.com>; wrote:
>
> Like Kyle mentioned the thing that 0-RTT adds to this is infinite
> replayability. As mentioned in the other thread we have ways to reduce the
> impact of infinite replayable data for TLS, making it reasonably replay
> safe.
>

That too is a mis-understanding. The deeper problem is that a third party
can do the replay, and that forward secrecy is gone for what likely is
sensitive data. Neither is the case with ordinary retries.

-- 
Colm