restoring SmartCard key with off-card copy

[Peter Lebbing]

On 26/09/11 23:11, Achim Cloer wrote:
> During generating the keys, the pgp card is also generating a off-card copy.
> But we fail to import this backup into OpenPGP.

It's been a while since I played with it, but it worked then. From the man page,
under --edit-key:

bkuptocard file

 Restore the given file to a card. This command may be used to restore a
backup key (as generated during card initialization) to a new card. In almost
all cases this will be the encryption key. You should use this command only with
the corresponding public key and make sure that the file given as argument is
indeed the backup to restore. You should then select 2 to restore as encryption
key. You will first be asked to enter the passphrase of the backup key and then
for the Admin PIN of the card.


So you can restore the key to the card using that command, after starting the
following from the command prompt:

gpg --edit-key <yourkey>


And the reason you can't import it as a normal secret key, is that the backup is
purely the RSA secret material instead of the bundle of information referred to
as a secret key in OpenPGP.

Your first message made it to the list, by the way.

Good luck,

Peter.

-- 
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