Re: [MLS] Use Cases for avoiding Forward Secrecy

Dave Cridland <dave@cridland.net> Fri, 02 March 2018 09:51 UTC

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From: Dave Cridland <dave@cridland.net>
Date: Fri, 2 Mar 2018 09:51:00 +0000
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To: Russ Housley <housley@vigilsec.com>
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Subject: Re: [MLS] Use Cases for avoiding Forward Secrecy
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On 1 March 2018 at 15:11, Russ Housley <housley@vigilsec.com> wrote:
> This is similar to the approach used in some email environments.  The email
> message is decrypted for reading, and then encrypted in a separate archive
> key for storage.

Sure, but that explicitly means that messages within the archive can
no longer be authenticated, doesn't it?

That, in turn, is a clear downgrade from the NCSC's SAKKE dictat. For
all its faults, that is providing a secure archive that the enterprise
has access to via an offline key escrow.

If I'm wrong here please don't hesitate to correct me.

Dave.