How to enable the integrated fingerprint reader with ThinkFinger

From ThinkWiki
Jump to: navigation, search

NB: ThinkFinger has been inactive for two years. It was removed from Debian because of this.

See How to enable the integrated fingerprint reader for up-to-date instructions on using the fingerprint reader on ThinkPads.

This page deals with an (apparently dead) project called ThinkFinger which had similar goals to fprint and BioAPI.

N.B.: The fingerprint reader is not a very secure device and may give a false sense of security. There has been quite a bit of research by a hacker named Starbug, a member of the Chaos Computer Club, Berlin, Germany. He outlined in two very good talks how to forge each and every available fingerprint sensor available at the cost of a few euros, using materials from your local hardware store, a digicam and a laser printer! Here are some links:

Installing ThinkFinger

From source

Download thinkfinger-0.3.tar.gz from the homepage and unpack it somewhere, make sure you have the gcc compiler, libtool, pkg-config, libusb-dev and libpam0g-dev installed, then:

$ cd thinkfinger-0.3

$ ./configure --prefix=/usr --sysconfdir=/etc --with-securedir=/lib/security --with-birdir=/etc/pam_thinkfinger

$ make

# make install

/lib/security is the directory, where PAM assumes its modules on Debian and openSUSE, it may vary for your distro!

"make install" doesn't create the birdir we specified (where ThinkFinger will store users' biometric info), so create it:

# mkdir /etc/pam_thinkfinger

If everything went OK assert that you find in /lib/security typing:

$ ls /lib/security

From package


Packages arrived in Debian experimental on Aug 2nd, 2007 (cf. bug #409563). To access the experimental packages via apt, add the following lines to your sources.list:

# experimental
deb experimental main contrib non-free
deb-src experimental main contrib non-free

where of course you may replace with your mirror of choice. Just make sure that it hosts the experimental repositories.

# aptitude update

# aptitude install libthinkfinger0 libpam-thinkfinger thinkfinger-tools

should then get you up and running.

To make everything work you'll have to have permission to work the device ($ sudo adduser myself plugdev worked for me), and you'll also have to follow instructions below about adding the device to your PAM methods.




Add PPA repositories to your sources.list:

deb gutsy main restricted universe multiverse
deb-src gutsy main restricted universe multiverse

Install necessary packages:

$ sudo apt-get install thinkfinger-tools libpam-thinkfinger


Hardy includes the latest thinkfinger and it is up to date with subversion. Install packages:

$ sudo apt-get install thinkfinger-tools libpam-thinkfinger

Update the pam configuration files:

$ sudo /usr/lib/pam-thinkfinger/pam-thinkfinger-enable

Enroll your fingerprint (creates $HOME/.thinkfinger.bir). If this gives an error about claiming the USB device then a reboot was claimed to work, but in fact it may just be a permissions problem.

Do not try to enroll using 'sudo' - it will cause hidden permission problems

$ tf-tool --acquire

Check fingerprint enrollment

$ tf-tool --verify

You can expect everything to work correctly. Note that you still have to enter your username if prompted but will be able to swipe your finger instead of the password. The prompt will usually be "Password or swipe finger"

  • Graphical login
  • Text console login
  • sudo
  • screen lock/screen saver
  • Administrative password prompt (eg for update or package managers). (Note no "or swipe finger" in prompt).

After installing from the normal repositories coming with Ubuntu 8.10, you would have to press enter after sweeping finger. (This bug: Therefore Jon Oberheide made an update that can be found here: (As of 2/3/09, this no longer seems to be the case. Just proceed to the install step.)

Add the PPA repositories to your source.list (/etc/apt/source.list):

deb intrepid main
deb-src intrepid main

Update installer:

$ sudo apt-get update

And install:

$ sudo apt-get install thinkfinger-tools


The same package by Jon Oberheide is necessary, as with Intrepid, though the package thinkfinger-tools is installed by default.

Add key:

$ sudo apt-key adv --recv-keys --keyserver F2A12FABE936A7BBDC4EA33351DB180D1323E149

Add the PPA repositories to your source.list (/etc/apt/source.list):

deb jaunty main
deb-src jaunty main

Update installer:

$ sudo apt-get update

And install:

$ sudo apt-get install thinkfinger-tools libpam-thinkfinger


The syntax of udev rules is changed due to Karmic's new udev package. The correct rules should be:

# SGS Thomson Microelectronics Fingerprint Reader
ENV{ID_VENDOR_ID}=="0483", ENV{ID_MODEL_ID}=="2016", SYMLINK+="input/thinkfinger-%k", MODE="0660", GROUP="fingerprint", ENV{GENERATED}="1"

# the also-needed uinput device
KERNEL=="uinput", MODE="0660", GROUP="fingerprint"

Otherwise udev would accidentally change the ownership of /dev/null so that gdm would fail to start.


From a working Karmic, upgrade to Lucid gave me a somewhat broken ThinkFinger.

The scanner still works, but (in X windows) you need to hit "Enter" after doing a scan. The scanner works fine while in terminal mode.

This is almost definitely because of the xorg version, see this message with no response for more info:

There is a PPA with working ThinkFinger for Lucid. At least it works fine on my Z61m. See here
ThinkFinger can be installed through Ubuntu Software Centre/Synaptic Package Manager/Terminal without special repositories enabled in Lucid. Search "ThinkFinger and install thinkfinger-tools (Synaptic/Software Centre), or type "sudo apt-get install thinkfinger-tools" (Terminal).

Fedora/Fedora Core

# yum install thinkfinger


# emerge sys-auth/thinkfinger


openSUSE 10.2 includes the package "libthinkfinger" (version 0.1-7) - you will find newer packages here.

Testing the driver

Now the driver is installed and should be working. You can try it (as root) with

# tf-tool --acquire


# tf-tool --verify

This will ask you to swipe your finger three times, save the fingerprint to /tmp/test.bir and then verify your fingerprint with the bir-file.

Configuring PAM to use ThinkFinger

Now you can configure PAM to use ThinkFinger:

Open /etc/pam.d/common-auth (In FC6, F7, and Gentoo, this file is /etc/pam.d/system-auth):

# nano -w /etc/pam.d/common-auth

Add this line before any pam_unix or pam_unix2 directives:

auth     sufficient

If your PAM uses the pam_unix and not the pam_unix2 module, you need to pass a specific argument in the /etc/pam.d/common-auth directive to make it consider the password entered at the pam_thinkfinger prompt.

auth     required try_first_pass

For instance, /etc/pam.d/common-auth looks like this:

auth    sufficient
auth    required nullok_secure try_first_pass

On openSUSE 10.2, it looks like this now:

auth    required
auth    sufficient
auth    required

On Ubuntu 8.10 - Intrepid Ibex you should just add the following line the the /etc/pam.d/common-auth file so it looks like this:

# here are the per-package modules (the "Primary" block)
auth	sufficient
auth	[success=1 default=ignore] try_first_pass nullok_secure
# here's the fallback if no module succeeds

On Ubuntu 9.04, you don't need to edit manually, just type:

# sudo /usr/lib/pam-thinkfinger/pam-thinkfinger-enable

Now we are ready to add users to thinkfinger. You can add a fingerprint for a user with:

# tf-tool --acquire $USERNAME

This may not work for you. Please read the Intrepid Ibex point in the discussion to this page.

Now the user should be able to login with his finger instead of the password.

If you would like to use thinkfinger for su, you have to enroll the fingerprint for root user with:

# tf-tool --acquire root

You should see the "Password or swipe finger:" prompt when trying to sudo or su. If you don't, you probably do not have the "User level driver support" compiled into your kernel or the "uinput" module loaded!


In Fedora 7, the package has been modified in such a way as to make doing this unnecessary.

If you'd like to be able to unlock your screen using the fingerprint reader, you must have current versions of xscreesaver (>~5.03) or gnome-screensaver (>~2.18.2). Then you must give yourself access to the fingerprint reader and your bir-file, because unlike login/gdm/su/sudo, both gnome-screensaver and xscreensaver do not run as root. The following procedure will make the fingerprint reader accessible to members of the "fingerprint" group.

Make the group: # groupadd fingerprint

Save the following as /etc/udev/rules.d/60-thinkfinger.rules and run # sudo /sbin/udevtrigger. If you are using a Debian-based distribution, it is likely you are affected by the following bug where you need to replace udevtrigger with udevadm trigger (with the space!) in order for the following to work. You may need to reboot for this to take effect.

# udev rules file for the thinkfinger fingerprint scanner
# gives access to the fingerprint reader to those in the "fingerprint" group
# Taken from:
# which was taken and modified from:

# SGS Thomson Microelectronics Fingerprint Reader
SYSFS{idVendor}=="0483", SYSFS{idProduct}=="2016", SYMLINK+="input/thinkfinger-%k", MODE="0660", GROUP="fingerprint"

# the also-needed uinput device
KERNEL=="uinput", MODE="0660", GROUP="fingerprint"

Finally, add the following lines at the end of /etc/pam.d/gnome-screensaver:

auth    sufficient
auth    required try_first_pass nullok_secure

Per user:

  1. Add him to the group: # gpasswd -a $USERNAME fingerprint
The following steps do not need to be done in Ubuntu Intrepid as the bir files are handled differently.
  1. Make him owner of his bir-file: # chown $USERNAME:root /etc/pam_thinkfinger/$USERNAME.bir
  2. Give him read-only access to his bir-file: # chmod 400 /etc/pam_thinkfinger/$USERNAME.bir
  3. Give "execute only" access to everyone for the /etc/pam_thinkfinger/ directory: # chmod o+x /etc/pam_thinkfinger (WARNING: this opens up security a little).


This problem should be solved if you're using sudo >= 1.6.9p9. Links: [1], [2], [3]

gksu/gksudo doesn't work correctly. It just stays invisible. When starting a su privileged application such as synaptics you will not get prompted for the password. Nevertheless you can swipe your finger and it should authenticate you. Starting synaptics twice makes gksudo visible.

There are two possibilities to solve it:

  • Changing the string "Password or swipe finger:" to a plain "Password:" (like sudo normally would do) in the file pam/pam_thinkfinger.c of the thinkfinger source directory. Of course, in the console you will then only see a "Password:" instead of "Password or swipe finger:" but this is still more usefull than having gksu/gksudo crashing everytime.
  • Patching libgksu with the following patch. This is also a nasty hack until a better solution is implemented.
--- libgksu-2.0.3/libgksu/libgksu.c.orig	2007-06-17 16:00:24.000000000 +0200
+++ libgksu-2.0.3/libgksu/libgksu.c		2007-06-17 16:00:47.000000000 +0200
@@ -2663,7 +2663,7 @@
       for (counter = 0; counter < 50; counter++)
-	  if (strncmp (buffer, "GNOME_SUDO_PASS", 15) == 0)
+	  if (strncmp (buffer, "GNOME_SUDO_PASS", 15) == 0 || strncmp (buffer, "Password or swi", 15) == 0)
 	  read_line (parent_pipe[0], buffer, 256);
@@ -2675,7 +2675,7 @@
       if (context->debug)
 	fprintf (stderr, "brute force GNOME_SUDO_PASS ended...\n");
-      if (strncmp(buffer, "GNOME_SUDO_PASS", 15) == 0)
+      if (strncmp(buffer, "GNOME_SUDO_PASS", 15) == 0 || strncmp(buffer, "Password or swi", 15) == 0)
 	  gchar *password = NULL;
 	  gboolean prompt_grab;


Integration in KDE and kdm seems not to be easily possible now. There is a filed bug at where you can vote for this.

Moreover, kdm in openSUSE 10.3 and in Kubuntu 8.10 crashes when pam_thinkfinger is enabled. A possible "workaround" is downgrading to thinkfinger 0.2.2.

Another workaround is to use Fprint from [4] which works quite nicely on my X61s and Kubuntu Hardy.

This Howto was copied from Installing Ubuntu 6.06 on a ThinkPad T43#Fingerprint_Reader and then slightly modified.

Fix for the fingerprint reader getting too hot

If you notice that your fingerprint reader occasionally gets very hot then you might be interested in this section. Thanks to Tino Keitelon the linux-thinkpad mailing list for the solution.

Collect info

First we need to determine if the reader is not on autosuspend mode. Open a terminal and run:

for i in `find /sys/devices/*/*/usb* -name level` ; do echo -n "$i: " ; cat $i ; done

We care about the devices that are with "on" state and we need to determine if one of those is the reader. So for each of those run something like:

cat /sys/devices/pci0000\:00/0000\:00\:1a.0/usb1/1-2/idVendor 

cat /sys/devices/pci0000\:00/0000\:00\:1a.0/usb1/1-2/idProduct 

Use the corresponding path of the devices that you got with "on" state and then compare the output with the output of the lsusb command. An example:

lsusb output: Bus 001 Device 004: ID 0483:2016 SGS Thomson Microelectronics Fingerprint Reader

Which matches the output above (0483:2016).

Enable autosuspend

Once you have determined the path of your reader then become root with su - and:

echo "auto" > /sys/<path-to-device>/power/level

Alternatively, if you're using Ubuntu:

echo auto | sudo tee /sys/<path-to-device>/power/level

After this, the fingerprint reader should be in "autosuspend" and will not get hot anymore. And it will still work as normal.

Making the changes permanent

The above will only work for the current session (until the next reboot). If you want to make the change persistent, do one of the following:

Using udev (recommended)

The simplest way to do this is to create a udev rule (requires no additional tools):

Put the following in /etc/udev/rules.d/69-fingerprint-sleep.rules

ATTR{idVendor}=="0483", ATTR{idProduct}=="2016", SUBSYSTEMS=="usb", ACTION=="add", ATTR{power/level}="auto"

(exchange 0483 and 2016 with what you found above if the numbers are different)

Using sysfsutils

Alternatively, if you have sysfsutils installed, edit the file /etc/sysfs.conf and add the line

<path-to-device>/power/level = auto

Following the above example, that would be

devices/pci0000\:00/0000\:00\:1a.0/usb1/1-2/power/level = auto

Using init scripts

If, for some reason, neither of the two above methods don't work, you can install an init script:

sudo gedit /etc/init.d/ReaderNoMoreHot

Paste the following into it:

echo "auto" > /sys/<path-to-device>/power/level

Save and close. Then:

sudo chmod 755 /etc/init.d/ReaderNoMoreHot
sudo update-rc.d ReaderNoMoreHot defaults 90

--Lunatico 19:19, 1 August 2008 (CEST), extended by --Michaelthomas h 23:36, 9 August 2008 (CEST)

For the init script above, you can use the following more elaborate script, which does all the work for you of identifying the <path-to-device>. This can be useful since the USB device id can change under various circumstances (kernel upgrade etc).


# find the fingerprint reader and change its power level to autosuspend

usbname="SGS Thomson Microelectronics Fingerprint Reader"
usbid=$(lsusb |grep "$usbname" |cut -d' ' -f6);
[[ -z $usbid ]] && echo "USB Device \"$usbname\" not found" && exit 1

unset failed_bool
find /sys/devices/*/*/usb* -name idVendor -print | (
  while read vfile; do
    dir=$(dirname $vfile);
    if [[ $vendor:$product = $usbid ]]; then
      [[ $old_level = auto ]] || echo auto >$plevel_file || failed_bool=1
  if [[ $failed_bool ]]; then
    echo "Failed to set the fingerprint reader's power level to 'auto'."
    exit 1

Here is an alternate script. The code is cleaner and it's about 20x faster (updated for jaunty):


# find the fingerprint reader and change its power level to autosuspend

find_prod="Biometric Coprocessor"

for devdir in /sys/class/usb_*/*/device; do
  [[ -r $devdir/manufacturer ]] || continue
  [[ $manuf = $find_manuf ]] || continue;
  [[ $prod = $find_prod ]] || continue;
  # if we get here then we have the right device!
  # if it is already set properly then exit silently:
  [[ $old_level = auto ]] && exit 0
  # if we successfully change it then exit silently:
  echo auto >$plevel_file && exit 0
  echo "Failed to set the fingerprint reader's power level to 'auto'."
  exit 1

# if we make it through the for loop without exiting, the search failed
echo "Could not find the $find_manuf $find_prod (fingerprint reader)"
exit 1