Subject: [TLS] Murray Kucherawy's No Objection on draft-ietf-tls-external-psk-guidance-04: (with COMMENT)

From: Murray Kucherawy via Datatracker <[email-masked]>
Date: Tue, 14 Dec 2021 22:31:49 -0800

Murray Kucherawy has entered the following ballot position for
draft-ietf-tls-external-psk-guidance-04: No Objection

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COMMENT:
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Thanks to Martin Thomson for his ARTART review.

A stylistic point: The Abstract is made up of five sentences all of which start
"This document".  It's a bit of a rigid read.  Maybe something like this?

   This document provides usage guidance for external Pre-Shared Keys
   (PSKs) in Transport Layer Security (TLS) 1.3 as defined in RFC 8446.
   It lists TLS security properties provided by PSKs under
   certain assumptions, and then demonstrates how violations of these
   assumptions lead to attacks.  It also discusses PSK use cases
   and provisioning processes.  Advice for
   applications to help meet these assumptions is provided.  Finally,
   it lists the privacy and security properties that are not provided by
   TLS 1.3 when external PSKs are used.

Section 4.1 contains this, which I can't quite parse:

   To illustrate the rerouting attack, consider the group of peers who
   know the PSK be A, B, and C.

Should there be a "to" after "PSK"?

In Section 8:

   Each endpoint SHOULD know the identifier of the other endpoint with
   which its wants to connect and SHOULD compare it with the other

s/its/it/

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From: Russ Housley <[email-masked]>
Date: Wed, 22 Dec 2021 00:48:09 -0500

Thanks.  I swapped two of your sentence so that the two sentences about assumptions are one after the other.

> Should there be a "to" after "PSK"?

I suggest:

   To illustrate the rerouting attack, consider three peers, A, B,

>   which its wants to connect and SHOULD compare it with the other

Fixed.

Russ