Re: [TLS] 1rtt thoughts

Eric Rescorla <ekr@rtfm.com> Mon, 14 July 2014 17:49 UTC

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From: Eric Rescorla <ekr@rtfm.com>
Date: Mon, 14 Jul 2014 10:49:08 -0700
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To: Adam Langley <agl@imperialviolet.org>
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Subject: Re: [TLS] 1rtt thoughts
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On Mon, Jul 14, 2014 at 10:27 AM, Adam Langley <agl@imperialviolet.org>
wrote:

> 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.
>

Indeed, it's required by TLS.

-Ekr


> 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
>
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