https://www.schiessle.org/articles/2006/08/07/login-with-gnupg-smartcard/
https://forums.puri.sm/t/require-librem-key-for-pureos-login-and-sudo/7440/6
https://access.redhat.com/documentation/en-us/red_hat_enterprise_linux/7/html-single/linux_domain_identity_authentication_and_policy_guide/index#smart-cards
https://blog.g3rt.nl/luks-smartcard-or-token.html