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Re: [TLS] Distinguishing between external/resumption PSKs

Richard Barnes <rlb@ipv.sx> Thu, 19 September 2019 20:57 UTC

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From: Richard Barnes <rlb@ipv.sx>
Date: Thu, 19 Sep 2019 16:57:17 -0400
Message-ID: <CAL02cgRdeP6noogLiVXzthKGMNGq7gyFhPKqHGQCsrACg9Cs5A@mail.gmail.com>
To: Nico Williams <nico@cryptonector.com>
Cc: Christian Huitema <huitema@huitema.net>, "tls@ietf.org" <tls@ietf.org>
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Subject: Re: [TLS] Distinguishing between external/resumption PSKs
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I don't think anyone's asking for these cases to be differentiable on the
wire.  The question is whether the *server* can differentiate, in
particular, the application running on the server.

--Richard

On Thu, Sep 19, 2019 at 2:36 PM Nico Williams <nico@cryptonector.com> wrote:

> On Thu, Sep 19, 2019 at 08:06:26AM -1000, Christian Huitema wrote:
> > There is also a privacy angle. From a privacy point of view, it is
> > very nice that PSK cannot be distinguished from session resumption.
>
> This.
>
> PSK is the right way to, for example, integrate Kerberos into TLS 1.3
> now.  But it's no eavesdropper's business whether a session used
> Kerberos for setup or resumption tickets.
>
> Nico
> --
>

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