Marco Trevisan authored Nov 14, 2020 and Carlos Garnacho committed Sep 05, 2023

The smartcard plugin of g-c-c has been based on the usage of NSS API,
unfortunately this means that, in order to be able to fetch the PKCS #11
devices, the system must provide a shared certificate NSS database that
is not standard in most distributions outside the Fedora / RH world.

Also, this database has to be pre-filled with PKCS #11 libraries to get
the available one, not fully respecting the p11-kit modules standard
(even though by default it now relies on a p11-kit-proxy library that de
facto follows this).

As per this, it's currently quite hard to get GDM to use smartcard
authentication working both using pam-sss or pam-pkcs11 in most distros.

This also was introducing another level of abstraction, while using the
p11-kit libs is nowadays preferred.

Said that, it made sense to finally use some standard libraries so that
smartcard devices supported by p11-kit can be handled without any
further action.

While we could support multiple backend...