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Re: [TLS] Negotiating with known_configuration

Martin Thomson <martin.thomson@gmail.com> Tue, 21 July 2015 11:10 UTC

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Date: Tue, 21 Jul 2015 04:10:56 -0700
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From: Martin Thomson <martin.thomson@gmail.com>
To: Eric Rescorla <ekr@rtfm.com>
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Subject: Re: [TLS] Negotiating with known_configuration
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On 21 July 2015 at 04:04, Eric Rescorla <ekr@rtfm.com> wrote:
> - The client indicates configuration ID and cryptographic configuration,
>   including the cipher suites and cryptographic extensions. This
>   MUST replicate the server's selection from a previous handshake


That's not going to work if there was no previous session.  For
instance, if the configuration was learned out of band.  It also
implies that the selection can come from ANY previous session, where I
think that it only makes sense to identify the session where the
configuration was learned.

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