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Re: [TLS] 0.5 RTT

Martin Thomson <martin.thomson@gmail.com> Tue, 23 February 2016 21:38 UTC

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Date: Tue, 23 Feb 2016 13:38:57 -0800
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From: Martin Thomson <martin.thomson@gmail.com>
To: Hugo Krawczyk <hugo@ee.technion.ac.il>
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Cc: Karthikeyan Bhargavan <karthik.bhargavan@gmail.com>, "tls@ietf.org" <tls@ietf.org>
Subject: Re: [TLS] 0.5 RTT
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On 23 February 2016 at 13:24, Hugo Krawczyk <hugo@ee.technion.ac.il> wrote:
> As for downgrades, this will be discovered by the server when receiving the
> client's Finished message.

Won't a downgrade be detected by the client when it fails to decrypt
the server's data?  If the server was given a false impression about
the client's capabilities, then that can only happen if it receives a
different ClientHello to the one the client sent.

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