Re: [Mathmesh] [Cfrg] A different approach to key escrow

Phillip Hallam-Baker <> Tue, 10 September 2019 03:02 UTC

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From: Phillip Hallam-Baker <>
Date: Mon, 9 Sep 2019 23:02:41 -0400
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To: Nico Williams <>
Cc: Michael Richardson <>,,
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Subject: Re: [Mathmesh] [Cfrg] A different approach to key escrow
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On Mon, Sep 9, 2019 at 12:38 PM Nico Williams <>; wrote:

> Speaking of which, how does master secret change work?

That might not be so critical with the changes I made to the way accounts

The master secret for the Mesh is only used in the management of the user's
Mesh devices. It is no longer something that is exposed to other people.
Only the account keys are exposed to other users.

What we probably need to do is to go through the scenarios that would
require re-keying a personal Mesh.

The way that would have least impact on other systems would be to simply
create a parallel Mesh and then create an assertion 'the person who used to
have fingerprint X now has fingerprint Y'. And then various parties would
have to decide the extent to which they trust that assertion.