Framework 16 fingerprint support for Kubuntu 25.04

Hello everyone…new Framework 16 owner here!

I am wondering if anyone has got fingerprint support working on KUbubtu 25.04. I installed fprintd and pam-fprint and it partially works.

I can use fprintd-enroll to add fingerprints in Konsole, and they verify with fprintd-verify. However, the connection to the KDE User setup for fingerprint setup is not active - it does nothing when prompting the user to repeatedly touch the sensor after selecting a finger. I’m wary of editing the pam configuration files, as that can make the computer inaccessible.

I’d appreciate any guidelines or suggestions before I start entering bugs for the fprintd project team.

Thanks!
Paul

There’s a separate KDE package for fingerprint authentication; Arch’s wiki has great docs for this (and almost everything): https://wiki.archlinux.org/title/Fprint

In /etc/pam.d/ I’ve got a kde-fingerprint file that has:

#%PAM-1.0

auth       required                    pam_shells.so
auth       requisite                   pam_nologin.so
auth       requisite                   pam_faillock.so      preauth
-auth      required                    pam_fprintd.so
auth       optional                    pam_permit.so
auth       required                    pam_env.so

account    include                     system-local-login

password   required                    pam_deny.so

session    include                     system-local-login

If you’re got the right bits installed, this should already be there.

I also had to tweak the system-auth file in there, you can see the pam_fprintd.so line I added to it:

#%PAM-1.0

auth       required                    pam_faillock.so      preauth
# Optionally use requisite above if you do not want to prompt for the password
# on locked accounts.
-auth      [success=2 default=ignore]  pam_systemd_home.so
# chrish added this one:
auth       sufficient                  pam_fprintd.so
auth       [success=1 default=bad]     pam_unix.so          try_first_pass nullok
auth       [default=die]               pam_faillock.so      authfail
auth       optional                    pam_permit.so
auth       required                    pam_env.so
auth       required                    pam_faillock.so      authsucc
# If you drop the above call to pam_faillock.so the lock will be done also
# on non-consecutive authentication failures.

-account   [success=1 default=ignore]  pam_systemd_home.so
account    required                    pam_unix.so
account    optional                    pam_permit.so
account    required                    pam_time.so

-password  [success=1 default=ignore]  pam_systemd_home.so
password   required                    pam_unix.so          try_first_pass nullok shadow
password   optional                    pam_permit.so

-session   optional                    pam_systemd_home.so
session    required                    pam_limits.so
session    required                    pam_unix.so
session    optional                    pam_permit.so

Be careful messing with the system-auth file as you can mess things up enough to disable authentication (to prevent authentication or just allow anything).

My setup intentionally doesn’t allow fingerprint authentication at the login screen, only at the desktop for wake from sleep, sudo, applications (like 1Password), etc. Not sure if KUbuntu uses SDDM, but I see some sddm-* files in the pam.d directory that look promising if that’s something you want.

I’m using EndeavourOS, so I didn’t try to suggest packages to install, but the config stuff should all be the same.