[Webpush] Last-minute Review of Webpush Encryption

"Matthew A. Miller" <linuxwolf+ietf@outer-planes.net> Mon, 03 July 2017 16:23 UTC

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From: "Matthew A. Miller" <linuxwolf+ietf@outer-planes.net>
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Date: Mon, 3 Jul 2017 09:23:20 -0700
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Subject: [Webpush] Last-minute Review of Webpush Encryption
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 I was asked to review draft-ietf-webpush-encryption.

Overall I think this document is ready; I'd lightly recommend one
editorial change and have a callout that borders the line on editorial.

In Section 3.4 "Encryption Summary", I think it adds clarity to
explicitly stating the "L" inputs for the two final HKDFs.  I've
submitted PR #12 to that effect.

More concerning is that "keyid" is expected to be the "raw" ECDH public
key, which is almost certainly not a UTF-8 encoded string; this bends
the SHOULD in draft-ietf-httpbis-encryption-encoding.  It needs to be
called out more explicitly than I see so far, but I don't have any
specific text to start with.


-- 
- m&m

Matthew A. Miller