Re: [Ntp] Post NTS, Is shared key authentication interesting?

Harlan Stenn <stenn@nwtime.org> Mon, 25 May 2020 21:22 UTC

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From: Harlan Stenn <stenn@nwtime.org>
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Date: Mon, 25 May 2020 14:22:21 -0700
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Subject: Re: [Ntp] Post NTS, Is shared key authentication interesting?
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On 5/25/2020 6:29 AM, Daniel Franke wrote:
> Yes, shared-key authentication is still interesting.
> 
> Putting the MAC in an extension field is clearly how NTPv4 should have
> done things from the start,

Wow.  Exactly how would that have worked?

> but I don't see any benefit in changing
> until the legacy MAC field can be killed off entirely. So I would rather
> just pursue this as part of NTPv5 than adopt a MAC EF draft for NTPv4.
>
> I would like NTPv5's shared key authentication to be a little more
> closely integrated with NTS. Either accomplish it by doing a PSK TLS
> handshake for NTS-KE, or skip NTS-KE and have pre-shared S2C/C2S keys
> and a shorter cookie giving just a key ID.
> 
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-- 
Harlan Stenn <stenn@nwtime.org>
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