Re: [Ntp] Roughtime, getting started

Miroslav Lichvar <mlichvar@redhat.com> Mon, 15 August 2022 11:29 UTC

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Date: Mon, 15 Aug 2022 13:29:09 +0200
From: Miroslav Lichvar <mlichvar@redhat.com>
To: Hal Murray <halmurray@sonic.net>
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Subject: Re: [Ntp] Roughtime, getting started
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On Sat, Aug 13, 2022 at 08:31:43PM -0700, Hal Murray wrote:
> 6.4 Validity of Response
>   A client MUST check the following properties when it receives a
>   response. We assume the long-term server public key is known to the
>   client through other means.
> 
> If I can distribute valid long-term keys, I can use them to sign the 
> certificates for NTS-KE servers and don't need Roughtime to get started.

Right.

> Am I missing something?

Roughtime is about detecting server malfeasance. You will have a proof
that a server was a falseticker, either due to an attack, or much more
likely an issue with the upstream synchronization (e.g. bug in GPS
firmware).

What people will do with that information, I'm not sure.

-- 
Miroslav Lichvar