Re: [TLS] The future of external PSK in TLS 1.3

Peter Gutmann <pgut001@cs.auckland.ac.nz> Thu, 24 September 2020 10:02 UTC

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From: Peter Gutmann <pgut001@cs.auckland.ac.nz>
To: Filippo Valsorda <filippo@ml.filippo.io>, Hannes Tschofenig <Hannes.Tschofenig@arm.com>, Carrick Bartle <cbartle891@icloud.com>
CC: "tls@ietf.org" <tls@ietf.org>
Thread-Topic: [TLS] The future of external PSK in TLS 1.3
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Date: Thu, 24 Sep 2020 10:02:29 +0000
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Archived-At: <https://mailarchive.ietf.org/arch/msg/tls/CaANre2jW2XHunxrKrwJx5X2CA8>
Subject: Re: [TLS] The future of external PSK in TLS 1.3
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Filippo Valsorda <filippo@ml.filippo.io> writes:

>The average user of OpenSSL or BoringSSL or LibreSSL or Go crypto/tls or NSS
>or Java doesn't do SCADA, doesn't do IoT, doesn't do smart cards

How do you know that?  I don't know of any data supporting that (I'd love to
see it if you've got it, non-web use of TLS is the submerged part of the
iceberg).  Taking "SCADA/IoT/etc" to be a placeholder for M2M or more
generally "non-web use", an awful lot of TLS gets done outside the web, which
uses it it completely different ways than web users do.  For example pretty
much all of the fancy features in TLS 1.3, both in the core protocol and the
endless add-ons, have no purpose or function in M2M communications.  So
perhaps the answer is to have two sets of requirements, one for web use, one
for everything else.  If you try for a one-size-fits-all approach you'll
either get the currently widespread "TLS == the web" or have to include two
mostly nonintersecting sets of options to cover web vs. M2M use.

Peter.