In the OpenPGPcard specification, there are two passwords: one is user-password and another is admin-password. In the specification, user-password is refered as PW1, and admin-password is refered as PW3. Besides, there is reset code, which enable a user to reset PW1.
Note that people sometimes use different words than “password” to refer same thing, in GnuPG and its applications. For example, the output explained above includes the word “PIN” (Personal Identification Number), and the helper program for input is named “pinentry”. Note that it is OK (and recommended) to include characters other than digits for the case of OpenPGPcard.
Besides, some people sometimes prefer the word “passphrase” to “password”, as it can encourage to have longer string, but it means same thing and it just refer user-password or admin-password.
Invoke GnuPG with the option --card-edit.
$ gpg --card-edit Application ID ...: D276000124010200F517000000010000 Version ..........: 2.0 Manufacturer .....: FSIJ Serial number ....: 00000001 Name of cardholder: Yutaka Niibe Language prefs ...: ja Sex ..............: male URL of public key : http://www.gniibe.org/gniibe.asc Login data .......: gniibe Signature PIN ....: not forced Key attributes ...: 2048R 2048R 2048R Max. PIN lengths .: 127 127 127 PIN retry counter : 3 3 3 Signature counter : 0 Signature key ....: 1241 24BD 3B48 62AF 7A0A 42F1 00B4 5EBD 4CA7 BABE created ....: 2010-10-15 06:46:33 Encryption key....: 42E1 E805 4E6F 1F30 26F2 DC79 79A7 9093 0842 39CF created ....: 2010-10-15 06:46:33 Authentication key: B4D9 7142 C42D 6802 F5F7 4E70 9C33 B6BA 5BB0 65DC created ....: 2010-10-22 06:06:36 General key info..: pub 2048R/4CA7BABE 2010-10-15 NIIBE Yutaka <email@example.com> sec> 2048R/4CA7BABE created: 2010-10-15 expires: never card-no: F517 00000001 ssb> 2048R/084239CF created: 2010-10-15 expires: never card-no: F517 00000001 ssb> 2048R/5BB065DC created: 2010-10-22 expires: never card-no: F517 00000001 gpg/card>
It shows the status of the card (as same as the output of gpg --card-status).
Then, GnuPG enters its own command interaction mode. The prompt is gpg/card>.
Firstly, I change PIN of card user from factory setting (of “123456”). Note that, by only changing user’s PIN, it enables “admin less mode” of Gnuk. “Admin less mode” means that admin password will become same one of user’s. That is, PW1 = PW3. Note that the length of PIN should be more than (or equals to) 8 for “admin less mode”.
gpg/card> passwd gpg: OpenPGP card no. D276000124010200F517000000010000 detected Please enter the PIN Enter PIN: 123456 New PIN Enter New PIN: <PASSWORD-OF-GNUK> New PIN Repeat this PIN: <PASSWORD-OF-GNUK> PIN changed.
The “admin less mode” is Gnuk only feature, not defined in the OpenPGPcard specification. By using “admin less mode”, it will be only a sigle password for user to memorize, and it will be easier if a token is used by an individual.
(If you want normal way (“admin full mode” in Gnuk’s term), that is, user-password and admin-password independently, please change admin-password at first. Then, the token works as same as OpenPGPcard specification with regards to PW1 and PW3.)
Lastly, I setup reset code, entering admin mode. Having reset code, you can unblock PIN when the token will be blocked (by wrong attempt to entering PIN). This is optional step.
gpg/card> admin Admin commands are allowed gpg/card> passwd gpg: OpenPGP card no. D276000124010200F517000000010000 detected 1 - change PIN 2 - unblock PIN 3 - change Admin PIN 4 - set the Reset Code Q - quit Your selection? 4 gpg: 3 Admin PIN attempts remaining before card is permanently locked Please enter the Admin PIN Enter Admin PIN: <PASSWORD-OF-GNUK> New Reset Code Enter New PIN: <RESETCODE-OF-GNUK> New Reset Code Repeat this PIN: <RESETCODE-OF-GNUK> Reset Code set. 1 - change PIN 2 - unblock PIN 3 - change Admin PIN 4 - set the Reset Code Q - quit Your selection? q
Then, I quit.