Re: [TLS] Negotiating with known_configuration

Eric Rescorla <ekr@rtfm.com> Tue, 21 July 2015 11:32 UTC

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From: Eric Rescorla <ekr@rtfm.com>
Date: Tue, 21 Jul 2015 13:31:41 +0200
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To: Martin Thomson <martin.thomson@gmail.com>
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Subject: Re: [TLS] Negotiating with known_configuration
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Yeah, or it could just have the semantics "this is my most preferred
configuration and if you send me anything compatible with it, I will
pick it"

-Ekr


On Tue, Jul 21, 2015 at 1:30 PM, Martin Thomson <martin.thomson@gmail.com>
wrote:

> 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.
>