Re: [Webpush] Last-minute Review of Webpush Encryption

Martin Thomson <martin.thomson@gmail.com> Tue, 04 July 2017 04:34 UTC

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From: Martin Thomson <martin.thomson@gmail.com>
Date: Tue, 4 Jul 2017 14:34:50 +1000
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To: "Matthew A. Miller" <linuxwolf+ietf@outer-planes.net>
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Subject: Re: [Webpush] Last-minute Review of Webpush Encryption
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On 4 July 2017 at 02:23, Matthew A. Miller
<linuxwolf+ietf@outer-planes.net>; wrote:
> 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.

I see your point, and I agree that this could be clearer, but I didn't
really like the unused variables.  See
https://github.com/webpush-wg/webpush-encryption/pull/13, which you
already approved :)

> 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.

I think that a note will help, yes.
https://github.com/webpush-wg/webpush-encryption/pull/14