- pam_fprint is a simple PAM module which uses libfprint's fingerprint processing and verification functionality for authentication. In other words, instead of seeing a password prompt, you're asked to scan your fingerprint.
The idea is to use the built-in fingerprint reader in some notebooks for login using PAM. This article will also explain how to use regular password for backup login method (solely fingerprint scanner is not recommended due to numerous reasons).
First, make sure you have one of the supported finger scanners. You can check if your device is supported by checking this list of supported devices. To check which one you have, type
You need to installand the group.
Some dependencies:, .
Once you made sure your reader is supported, you are good to go.
By default, only root has access to the device. You can create a signature from sudo, but then you can only use it for root user. The following solution from the Ubuntu forums may work for some people.
1. If the group plugdev doesn't exist, create it:
# groupadd plugdev
2. Add yourself to the group:
# gpasswd -a USER plugdev
3. Allow USB access:
# chgrp -R plugdev /dev/bus/usb/
Modify the auth section of
/etc/pam.d/login to this:
auth required pam_env.so auth sufficient pam_fprintd.so auth sufficient pam_unix.so try_first_pass likeauth nullok auth required pam_deny.so
This tries to use fingerprint login first, and if if fails or if it finds no fingerprint signatures in the give user's home directory, it proceeds to password login.
You can also modify other files in
/etc/pam.d/ using the same method, for example
/etc/pam.d/gdm for GNOME's fingerprint login or
/etc/pam.d/polkit-1 for GNOME PolicyKit Authentication.
Create fingeprint signature
Now you should be able to run the program under a normal user. To see the usage, run
$ man fprintd
Chose one of the fingers and run
You will be asked to scan the given finger 3 times. After that, the signature is created in
An alternate fingerprint reader gui. This works with libfprint-unstable which has support for the new Upeksonly readers, such as, the new Thinkpad W510 T510 T410 T420 Upeksonly reader with USB ID 147e:2016
Install as dependencyand .
Please make sure your user is a member of "plugdev" and "scanner" group if you use UPEK non-free library. You may also have to log out and back in for these changes to take effect.
# gpasswd -a USER plugdev # gpasswd -a USER scanner
fingerprint-polkit-agent conflicts with files in
/etc/xdg/autostart that must
"polkit-gnome-authentication-agent-1.desktop" and "polkit-kde-authentication-agent-1.desktop".
Edit your PAM configuration (e.g.,
Change the auth section to read:
auth required pam_env.so auth sufficient pam_fingerprint-gui.so auth sufficient pam_unix.so try_first_pass likeauth nullok auth required pam_deny.so
Add this to your ~/.bashrc file if you get an error saying that it can't connect to X desktop (see this for more details).
xhost + >/dev/null
Now run fingerprint-gui and register fingerprints for the current user. You will need to run fingerprint-gui and register fingerprints as all users you want to use the fingerprint reader, i.e. as root to use it for "su" login.