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Re: [MLS] [interim_transcript_hash]

Richard Barnes <rlb@ipv.sx> Fri, 11 October 2019 13:54 UTC

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From: Richard Barnes <rlb@ipv.sx>
Date: Fri, 11 Oct 2019 09:53:59 -0400
Message-ID: <CAL02cgTEdnjbg5c4psAgOCgJ_hBxrYmgCxJ5xoJjSJW7vVgO-Q@mail.gmail.com>
To: Pascal Junod <pascalj=40snap.com@dmarc.ietf.org>
Cc: Messaging Layer Security WG <mls@ietf.org>
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Subject: Re: [MLS] [interim_transcript_hash]
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Because if you did that, then you would have a circular dependency:

interim_transcript_hash
<= MLSPlaintext.confirmation
<= confirmation_key
<= GroupContext (via DeriveSecret)
<= interim_transcript_hash

This was a problem in earlier versions!

On Thu, Oct 10, 2019 at 10:02 Pascal Junod <pascalj=
40snap.com@dmarc.ietf.org> wrote:

> Hi !
>
> Just wondering whether there is a reason why the interim_transcript_hash
> value (necessary to build Welcome messages) value is not contained into
> the GroupContext structure.
>
> Best,
>
> Pascal
> _______________________________________________
> MLS mailing list
> MLS@ietf.org
> https://www.ietf.org/mailman/listinfo/mls
>

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