$ sudo apt install fprintd libpam-fprintd
fprintd-enroll -f right-middle-finger
enrolled a finger. For example:
$ fprintd-enroll -f right-middle-finger
Enrolling right-middle-finger finger.
Enroll result: enroll-stage-passed
Enroll result: enroll-stage-passed
Enroll result: enroll-stage-passed
Enroll result: enroll-stage-passed
Enroll result: enroll-stage-passed
Enroll result: enroll-stage-passed
Enroll result: enroll-stage-passed
Enroll result: enroll-completed
$ # then verify
$ fprintd-verify
Using device /net/reactivated/Fprint/Device/0
Listing enrolled fingers:
- #0: right-middle-finger
- #1: right-index-finger
Verify started!
Verifying: right-middle-finger
Verify result: verify-match (done)
All good. Now all that was needed was to add the fingerprint requirement to the authentication system, PAM. This is usually done by editing files in /etc/pam.d/ (there is one file per authentication context: login, sudo, gdm, polkit-1, etc), but I discovered that on Debian it could also be managed by pam_auth-update, a small utility that can fill the PAM configuration according to profiles defined in /usr/share/pam-configs/. Conveniently, Debian provides /usr/share/pam-configs/fprintd, which allows to enable fingerprint authentication everywhere, cleanly.
$ sudo pam-auth-update --enable fprintd
And that’s it!





