Re: [Ntp] Quick review of WGLC for status change for draft-ietf-ntp-update-registries

[Miroslav Lichvar <[e-mail]>]

On Mon, Aug 08, 2022 at 06:46:13PM -0700, Harlan Stenn wrote:
> Before I go on, what are the "conflicts with properly specified extension
> fields"?

Experimental EFs can conflict only with other experimental EFs, but
not EFs that have an RFC with the types assigned by IANA.

The idea is that you don't have to tell anyone that you are using an
experimental EF.

> > chrony does not support Autokey. It doesn't care that keys with some
> > specific IDs are generated automatically. It cannot authenticate as an
> > Autokey server and will not accept a response from an Autokey server.
> 
> Sure.  And if chrony tries to use a KeyID that is "out of range" with ntpd,
> what happens?

The same as if it was an "in the range" unknown key?

> I'm curious about the collision with an NTS extension field.  I suspect that
> was simply a result of poor programming on the implementor's side, but I
> could be wrong.

The value was chosen by the first NTS implementation. As the Autokey
values used by ntpd were not documented anywhere, we didn't realize
there was a conflict until it was too late.

Now, with this draft that we are discussing here all values will be
documented and a similar conflict will hopefully not happen again.

> 
> Earlier you wrote:
> 
> > With an
> > experimental extension field the user is responsible to enable it only
> > if the server is known to support it.
> 
> If that statement from you is correct, then was the collision with an NTS EF
> the result of responsible or irresponsible user behavior?

It was the result of ntpd not following the Autokey specification.
We didn't have an experimental range defined yet.

-- 
Miroslav Lichvar