I’ve never ever had any problem using fingerprint authentication on openSUSE 42.1, it worked just out of the box, but when I switched back to Fedora (again), I had some issues configuring it.
On Fedora 26, by default, fingerprint authentication works only for logins but not for sudo. To enable this:
authconfig --enablefingerprint --update
If you’re using an older version of Fedora you can also use:
authconfig-tui
After enabling fingerprint authentication, I modified /etc/pam.d/sddm as follows:
auth [success=done ignore=ignore default=bad] pam_selinux_permit.so
auth sufficient pam_fprintd.so
auth substack password-auth
-auth optional pam_gnome_keyring.so
-auth optional pam_kwallet5.so
-auth optional pam_kwallet.so
auth include postlogin
Enroll your fingerprints:
fprintd-enroll -f [fingername]
We’re ready to authenticate on our system using the fingerprint reader.