Re: [TLS] WGLC for draft-ietf-tls-ticketrequests

Eric Rescorla <ekr@rtfm.com> Sun, 02 February 2020 17:10 UTC

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From: Eric Rescorla <ekr@rtfm.com>
Date: Sun, 2 Feb 2020 09:09:47 -0800
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To: Tommy Pauly <tpauly=40apple.com@dmarc.ietf.org>
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Subject: Re: [TLS] WGLC for draft-ietf-tls-ticketrequests
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On Sun, Feb 2, 2020 at 6:43 AM Tommy Pauly <tpauly=
40apple.com@dmarc.ietf.org> wrote:

> > On Feb 2, 2020, at 3:52 AM, Viktor Dukhovni <ietf-dane@dukhovni.org>
> wrote:
>
> On the other hand, the proposed sentinel value indicates “I’d like to
> reuse tickets if I can”, but without any additional signaling from the
> server about the support of ticket reuse, a server response containing no
> tickets is ambiguous—maybe it means ticket reuse is fine; maybe it means
> the server isn’t giving out any more tickets and won’t allow resumption. It
> is much clearer if there is a bidirectional signal about negotiating ticket
> reuse.
>
>
It's worth noting that because tickets are delivered serially and without a
leading count it's actually somewhat ambiguous no matter what. The server
might just decide to interleave data with tickets. I do agree it's somewhat
more ambiguous in the reuse case.

-Ekr