Re: [TLS] Negotiating with known_configuration

Martin Thomson <martin.thomson@gmail.com> Tue, 21 July 2015 11:30 UTC

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Date: Tue, 21 Jul 2015 04:30:12 -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 04:12, Eric Rescorla <ekr@rtfm.com> wrote:
>
> Yes, that's an issue. Not entirely sure what to do about other than
> have the server provide its negotiation preferences out of band
> in that case.

I think that we could handle that at the point we define an
out-of-band configuration priming mechanism.  I don't think we need a
full negotiation model for the server.  A simple option would list the
server's preference order for suites and so forth in its configuration
advertisement; the client would then pick from that.