Re: [TLS] 1rtt thoughts

Adam Langley <agl@imperialviolet.org> Mon, 14 July 2014 17:27 UTC

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Date: Mon, 14 Jul 2014 10:27:35 -0700
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From: Adam Langley <agl@imperialviolet.org>
To: Michael StJohns <msj@nthpermutation.com>
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Subject: Re: [TLS] 1rtt thoughts
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On Mon, Jul 14, 2014 at 10:16 AM, Michael StJohns
<msj@nthpermutation.com> wrote:
> A
> TLS1.2 server receiving things in this order discards the ClientKeyExchange
> with an out of sequence error, and then starts the handshake normally with
> the receipt of the ClientHello.

I've never encountered a TLS 1.2 implementation that will discard an
unexpected handshake message like that as opposed to sending a fatal
alert (maybe) and closing the connection.

We could refine TLS 1.2 processing, of course, but if you were
expecting that to be backwards compatible with existing code then I
fear it won't work.


Cheers

AGL

-- 
Adam Langley agl@imperialviolet.org https://www.imperialviolet.org