My key setup is as follows:
sec dsa3072/CA72E53A created: 2013-05-12 expires: never usage: SCA trust: ultimate validity: ultimate The following key was revoked on 2016-01-13 by DSA key CA72E53A ssb elg4096/ADBBBE42 created: 2013-05-12 revoked: 2016-01-13 usage: E ssb rsa4096/6A743003 created: 2016-01-13 expires: 2018-01-12 usage: E ssb rsa4096/A57F2B30 created: 2016-01-13 expires: 2018-01-12 usage: S
I am trying to transition to RSA subkeys as I want to use a Yubikey for my keys, but started out with a DSA/Elgamal key.
But when adding new subkeys I don't get the option to add an RSA (or DSA) key with custom parameters. Is this a result of having a DSA master key?
gpg> addkey Please select what kind of key you want: (3) DSA (sign only) (4) RSA (sign only) (5) Elgamal (encrypt only) (6) RSA (encrypt only) Your selection?
A workaround I am considering is genereting a new keypair just for authentication purposes (RSA/RSA), not publishing the public key and uploading that authentication key onto the yubikey, but I don't know if that is supported by the Yubikey and if it has other downsides.
Is it possible to have an RSA authentication subkey with a DSA master key or am I trying to do something silly and should I just bite the bullet and transition to a new RSA master key?
I am using GnuPG version 2.1.9.