[Ntp] The trick to timestamp with authentication

Watson Ladd <watsonbladd@gmail.com> Thu, 03 December 2020 05:44 UTC

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From: Watson Ladd <watsonbladd@gmail.com>
Date: Wed, 02 Dec 2020 21:44:04 -0800
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To: NTP WG <ntp@ietf.org>
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Subject: [Ntp] The trick to timestamp with authentication
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Dear NTP WG,

AES-GCM and Poly1305 are linear. In order to adjust the timestamp in
one step, it suffices to line everything up so that the hardware can
compute the correction in the same cycle as the stamp by isolating the
stamp in one block of the CWC hash.

This won't work with HMAC.

Sincerely,
Watson Ladd

-- 
Astra mortemque praestare gradatim

[Ntp] The trick to timestamp with authentication Watson Ladd
Re: [Ntp] The trick to timestamp with authenticat… Hal Murray
Re: [Ntp] The trick to timestamp with authenticat… Doug Arnold
Re: [Ntp] The trick to timestamp with authenticat… Hal Murray
Re: [Ntp] The trick to timestamp with authenticat… Doug Arnold
Re: [Ntp] The trick to timestamp with authenticat… James
Re: [Ntp] The trick to timestamp with authenticat… Dieter Sibold
Re: [Ntp] The trick to timestamp with authenticat… Miroslav Lichvar
[Ntp] Antwort: Re: The trick to timestamp with au… kristof.teichel
Re: [Ntp] Antwort: Re: The trick to timestamp wit… Miroslav Lichvar
Re: [Ntp] Antwort: Re: The trick to timestamp wit… Dieter Sibold
Re: [Ntp] Antwort: Re: The trick to timestamp wit… Philip Prindeville
Re: [Ntp] Antwort: Re: The trick to timestamp wit… Watson Ladd