DeveloperWiki:Managing the Master Key
Prepare your Smartcard
ccid package and start the
pcscd daemon. Insert your smartcard reader and check the output of
Creating the master key
gpg --card-edit. Type in
admin to enabled administration functions. All available commands can now be listed by issuing the
help command. Use the
sex commands to set some unimportant meta data.
To create a new key pair just type in
generate. Create a
3072 Bits key that does not expire and enter your data according to this example:
Real name: Pierre Schmitz Email address: firstname.lastname@example.org Comment: Arch Linux Master Key
Confirm that your USER-ID looks like
"Pierre Schmitz (Arch Linux Master Key) <email@example.com>". Generating the key will take some time. Note that the encryption key will be reduced to 1024 Bits.
If you created a backup of your key during creation you should secure it on an offline device and remove the key from your hard drive. E.g. use shred:
shred -u /home/pierre/.gnupg/sk_8DFDBF1F86872C2F.gpg
Now create a revoke key:
gpg -o master-key-revoke.asc --gen-revoke 6AC6A4C2
Choose no reason (0) if you are asked for one. Make sure to save this key on a secure and offline device (e.g. print it or use a thumb drive).
Signing the master key
Sign the master key using your packager key. For example using the master key id:
gpg --sign-key 6AC6A4C2
Double check you are using the right keys here!
Upload your master key now using:
gpg --send-keys 6AC6A4C2
You may also want to create a copy of your public key to publish elsewhere:
gpg --export --armor 6AC6A4C2 > firstname.lastname@example.org
Signing your own packager key
As you should trust yourself the most, just go ahead and sign your own packager key:
gpg --sign-key -u 6AC6A4C2 9741E8AC
Note that in this example your master key id is first and your packager key id last.
Upload your public key using:
gpg --send-keys 9741E8AC
Revoking a master key
Signing developer keys
Revoking developer keys
- Using the smartcard generates following errors without any apparent effect:
libusb could not open USB device /dev/bus/usb/001/006: Permission denied. libusb requires write access to USB device nodes.
Cause: gnupg has an internal ccid driver. This driver accesses the USB device node directly, without going through pcscd. However, gnupg's internal driver does not support the Gemalto USB reader anyway, so this message can be ignored.
- udev/packaging issue:
udevd: specified group 'pcscd' unknown
This is unproblematic: the pcscd daemon runs as root.
- Should we advice to create a backup during key creation or rather not?
- Is the passphrase only used for the backup key?
- Is the public key also stored on the card?
It probably is, but there is no apparent way to obtain it. Export it to some keyserver quickly.
- How should the
urlconfiguration be set?
A string pointing to a URL that stores your pubkey.
- What is the impact of setting
If you enable forcesig, you must enter the PIN for each single signature. This is recommended.