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Re: [openpgp] Deriving an OpenPGP secret key from a human readable seed

Michael Richardson <mcr+ietf@sandelman.ca> Thu, 17 October 2019 10:20 UTC

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From: Michael Richardson <mcr+ietf@sandelman.ca>
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Comments: In-reply-to Kai Engert <kaie@kuix.de> message dated "Thu, 17 Oct 2019 11:01:58 +0200."
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Date: Thu, 17 Oct 2019 12:21:27 +0200
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Subject: Re: [openpgp] Deriving an OpenPGP secret key from a human readable seed
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Kai Engert <kaie@kuix.de> wrote:
    > - look at existing encrypted email, an extract the key ID, to understand
    > which key needs to be recovered. But that might be a subkey ID, so
    > further searching is required to identify the ID of the master key?

Maybe they can't get access to their IMAP folder until they decrypt their
backup, so I think that this is a more reasonable concern.

But, I think you have over-constrained the problem space.

    >> I'm not personally very convinced about this general approach -- it's
    >> the equivalent of an unchangeable password that you've committed to
    >> publicly

    > Why do you consider it equivalent, if the seed was randomly generated,
    > and the list of words isn't influenced by the user?

It's equivalent to a system generated password.

--
Michael Richardson <mcr+IETF@sandelman.ca>, Sandelman Software Works
 -= IPv6 IoT consulting =-

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