Re: [MLS] Use Cases for avoiding Forward Secrecy

Dave Cridland <dave@cridland.net> Fri, 02 March 2018 10:55 UTC

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From: Dave Cridland <dave@cridland.net>
Date: Fri, 2 Mar 2018 10:55:15 +0000
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To: Katriel Cohn-Gordon <me@katriel.co.uk>
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Subject: Re: [MLS] Use Cases for avoiding Forward Secrecy
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On 2 March 2018 at 10:08, Katriel Cohn-Gordon <me@katriel.co.uk> wrote:
> On Fri, 2 Mar 2018, at 9:51 AM, Dave Cridland wrote:
>> Sure, but that explicitly means that messages within the archive can
>> no longer be authenticated, doesn't it?
>
> Do e.g. governments require that the archive consist of the actual encrypted messages that were transmitted over the wire? As opposed to having a trusted party, perhaps a "recorder" group member, re-encrypt them for archival.

Pass.

Currently the NCSC won't accredit any solution not based around
MIKEY-SAKKE for OFFICIAL and up, but - rather like MLS, actually - we
have a bunch of security outcomes but no indication of what drove the
decision, or indeed what's important.

Dave.