How to migrate my key from card to file?
olav at seyfarth.de
Sun Sep 6 01:24:52 CEST 2020
I did search but did not find a useful answer to my question. In 2017
someone else asked:
> During generating the keys on the GnuPG card, one can (and should)
> create some backup of the secret key into a file. It is totally
> unclear to me how to make something usefull out of this file, for
> example import it into a "normal" secret keyring to use it in case of
> the GnuPG card gets lost.
The discussion that followed explained how to create another CARD based
key from the backup. That is NOT my concern, I know how to do this.
Thus, I'd like to put this more specifically:
I want to no longer use a card (e.g. in order to be able to read old
messages on a mobile device, or in Thunderbird 78.2.1 WITHOUT the use of
GnuPG) but want to use the OLD CARD KEY.
I did create the key "on card"* (with --card-edit/admin/generate, NOT as
plain file and then with --keytocard). I do have a private_stub.gpg,
pubkey.gpg and sk_xxx.gpg.
*As I read in the above thread, the code actually generates the key as a
file, writes out a backup file and transfers it to the card. So maybe
I'd rather have used file based creation+backup-my-key+keytocard in the
first place, but I did not.
My question: Now that I have the above three files (and a working card
with the secret key on it), how can I use these to create a plain file
based private+public keypair from it?
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