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

Harlan Stenn <stenn@nwtime.org> Mon, 25 May 2020 21:47 UTC

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To: Daniel Franke <dfoxfranke@gmail.com>
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From: Harlan Stenn <stenn@nwtime.org>
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Date: Mon, 25 May 2020 14:47:04 -0700
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Subject: Re: [Ntp] Post NTS, Is shared key authentication interesting?
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On 5/25/2020 2:45 PM, Daniel Franke wrote:
> On Mon, May 25, 2020 at 5:22 PM Harlan Stenn <stenn@nwtime.org
> <mailto:stenn@nwtime.org>> wrote:
> 
> 
> 
>     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?
> 
> 
>  This is a bizarre question coming from a co-author of
> draft-mayer-ntp-mac-extension-field. What do you think would have been
> troublesome? If NTPv4 — the same version which introduced extension
> fields — had specified that everything following the header is an
> extension field, specified one such extension field containing a key-id
> and MAC, and forbidden NTPv3-style legacy MACs from appearing in v4
> packets, then everything would be straightforward, there would be no
> syntactic ambiguity, and RFC 7822 would not have been needed.

I stand in awe of your hubris.

-- 
Harlan Stenn <stenn@nwtime.org>
http://networktimefoundation.org - be a member!