fprintd-enroll times out

[pklaus]

I'm on Arch Linux (rolling release distro) with a very recent version of fprint: 0.8.0-1

After installing the modified libfprint library, running fprint-enroll times out with the following error:

[philipp@lion ~]$ fprintd-enroll 
list_devices failed: Failed to activate service 'net.reactivated.Fprint': timed out (service_start_timeout=25000ms)

Using examples/enroll and examples/verify works nicely with my 04f3:0c1a Elan though.

[iafilatov]

Hm, not really sure. If you compile and install libfprint with debug logging (autogen.sh), you'll get debug output in syslog. Also maybe check if fprintd is running?

[pklaus]

I'll see about the syslog. How can I check fprintd is running? Who's starting the daemon? fprintd-enroll? If so, is it terminating, when the tool ends?

Funny enough, my self-compiled version of fprint_demo works perfectly:

git clone git://github.com/dsd/fprint_demo.git
cd fprint_demo
export PKG_CONFIG_PATH=/usr/local/lib/pkgconfig
./configure --prefix=/usr/local
make
# running
LD_LIBRARY_PATH=/usr/local/lib/ ./src/fprint_demo

[pklaus]

Ah, I see. The syslog revealed the problem:

May 05 11:01:18 lion dbus-daemon[371]: [system] Activating via systemd: service name='net.reactivated.Fprint' unit='fprintd.service' requested by ':1.2425' (uid=1000 pid=14285 comm="fprintd-list philipp ")
May 05 11:01:18 lion systemd[1]: Starting Fingerprint Authentication Daemon...
May 05 11:01:18 lion fprintd[14286]: /usr/lib/fprintd: error while loading shared libraries: libfprint.so.0: cannot open shared object file: No such file or directory
May 05 11:01:18 lion systemd[1]: fprintd.service: Main process exited, code=exited, status=127/n/a
May 05 11:01:18 lion systemd[1]: fprintd.service: Failed with result 'exit-code'.
May 05 11:01:18 lion systemd[1]: Failed to start Fingerprint Authentication Daemon.

So that systemd thing has to get to know the new library path (/usr/local/lib)...

[pklaus]

So the problem was that the system didn't know about this additional library path "/usr/local/lib". When calling a tool from the command line, you can set the environment variable LD_LIBRARY_PATH (like in LD_LIBRARY_PATH=/usr/local/lib/ ./src/fprint_demo). But for the system wide library locations, the correct place to register them is /etc/ld.so.conf or a new .conf file in /etc/ld.so.conf.d/. As I'm using Arch Linux, the latter one is preferred. Here's what was needed to fix the problem:

echo "/usr/local/lib" | sudo tee /etc/ld.so.conf.d/usr_local_lib.conf
sudo ldconfig

Afterwards, the commands fprintd-enroll and fprintd-verify just work.

Thanks for your nice work on extending the library to the ELAN fp readers!

[iafilatov]

Thanks for your interest, Philipp! I hope it works ok for you because the size of the sensor on these Elan devices has some implications which are outside of my control as a driver dev.

[pklaus]

So I've been using your libfprint together with fprintd for system login and sudo for three weeks now. It's working well, although I have to swipe my finger slowly and entierly for it to succeed. It's not as "convenient" as on Windows but I guess it's also more secure. To compensate for the procedure being more prone to deviations in speed and finger angle, I registered multiple "fingers" but always actually swept my index finger (forefinger) so that there are more reference samples stored for it :-) Thanks for providing the lib!

[iafilatov]

I'm glad it works for you. I don't know and certainly make no claim about how it compares to Windows touch-mode operation in terms of security. There's no data to say whether it's more or less secure in practice. All I can say is that the algo that libfprint uses is well-studied and robust. If it actually matches your print, it's not by chance.

[neslinesli93]

Hi, I'm getting a similar problem: I can't get fprintd-enroll to work as it times out. Here are the contents of /var/log/syslog:

Aug 28 11:32:59 zenbook systemd[1]: Starting Fingerprint Authentication Daemon...
Aug 28 11:32:59 zenbook systemd[3422]: fprintd.service: Failed to set up mount namespacing: No such file or directory
Aug 28 11:32:59 zenbook systemd[3422]: fprintd.service: Failed at step NAMESPACE spawning /usr/local/libexec/fprintd: No such file or directory
Aug 28 11:32:59 zenbook systemd[1]: fprintd.service: Main process exited, code=exited, status=226/NAMESPACE
Aug 28 11:32:59 zenbook systemd[1]: fprintd.service: Failed with result 'exit-code'.
Aug 28 11:32:59 zenbook systemd[1]: Failed to start Fingerprint Authentication Daemon.

I've installed this library as well as fprintd from source, so it looks like a problem on fprintd end. Any idea?

[neslinesli93]

Well, eventually I solved this problem by building both fprintd and libfprint to /usr instead of /usr/local.

However I had to stop trying to integrate the fingerprint system inside PMA after noticing that maybe 1/20 tries is successful. Is there really anything we can do?

[iafilatov]

@neslinesli93 Tries of what? What did you mean when you said "verify and enroll seem to work perfectly" in the #21?

[neslinesli93]

Tries of fprintd-enroll, but they happened before I learned I had to swipe my finger on the sensor, from top to bottom.

Using that technique, I manage to enroll my finger with no failed attempts, but then running fprintd-verify results in a lot of false negatives, annoyingly