Re: [TLS] Erik Kline's No Objection on draft-ietf-tls-external-psk-importer-06: (with COMMENT)

[Benjamin Kaduk <[e-mail]>]

On Mon, Dec 28, 2020 at 10:50:20PM -0800, Erik Kline via Datatracker wrote:
> Erik Kline has entered the following ballot position for
> draft-ietf-tls-external-psk-importer-06: No Objection
> 
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> 
> 
> ----------------------------------------------------------------------
> COMMENT:
> ----------------------------------------------------------------------
> 
> [[ questions ]]
> 
> [ section 4.2 ]
> 
> * I'm insufficiently versed in TLS and HKDF to know for sure, but the text
>   about "replace the string" and the diagrammed example don't seem to agree,
>   **to my untrained eye**.  The example seems to show "imp binder" perhaps
>   concatenated with the "standard" sequence, rather than "imp binder"
>   /replacing/ "ext binder".
> 
>   Am I way off base here? In other words, should
> 
>     "ext binder" | "res binder" | "imp binder"
> 
>   actually be (if I understand the use of the word "replace" correctly):
> 
>     "imp binder" | "res binder"
> 
>   ?

I guess https://tools.ietf.org/html/rfc8446#section-7.1 does not cover this
very well either, but the '|' notation is just shorthand for "there are
multiple outputs, produced by using the different values as this input
field".  It's not concatenation, just a different output corresponding to
the different case of protocol operation.

Suggestions for how to clarify that would, of course, be most welcome!

Thanks,

Ben