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LightDM: can't login with password, only with fingerprint

I'm using an up-to-date Gentoo system (with fingerprint-gui 1.07) and lightDM-greeter as login manager.

I can login by fingerprint just fine (the same is true for any other auth with fingerprint: login at a TTY, su/sudo (TTY and GUI).

However, when I try to login at lightDM with just the password and NOT by fingerprint, I can't (wrong password, auth dialog starts over). When doing an auth in a terminal (TTY or gui) I am also asked to scan my finger, but if I enter the (same) password instead, it works without error.

relevant log file entries:

1. lightDM-greeter: unsuccessful auth with password
http://pastebin.com/EEb7DxkQ

2. lightDM-greeter: successful auth with fingerprint
http://pastebin.com/cRwGz9Wv

3. relevant lines from /etc/pam.d/system-auth (which gets included in the lightDM conf for pam):
auth            required        pam_env.so
auth            sufficient pam_fingerprint-gui.so -d try_first_identified
auth            required        pam_unix.so try_first_pass likeauth nullok
auth            optional        pam_permit.so

Thanks for your help!

flipsa
Permalink flipsa 
June 22nd, 2016 1:25pm
Please install Version 1.08.

W.U.
Permalink Wolfgang Ullrich 
June 22nd, 2016 6:09pm
I just did, but that didn't change anything.

The log is different this time though. I guess the interesting part is this:

Jun 22 19:32:49 tp fingerprint-helper[6981]: Starting identify.
Jun 22 19:32:49 tp fingerprint-helper[6981]: Message: Authenticating MY_USER_NAME
Jun 22 19:32:50 tp fingerprint-helper[6981]: ABS_MSG_PROMPT_SCAN.
Jun 22 19:32:58 tp pam_fingerprint-gui[6980]: Prompting password returned PAM_SUCCESS.
Jun 22 19:32:58 tp fingerprint-helper[6981]: Got SIGUSR2, EXIT_SUCCESS.
Jun 22 19:32:58 tp fingerprint-helper[6981]: Devices released.
Jun 22 19:32:58 tp pam_fingerprint-gui[6980]: Got empty password by keyboard.
Jun 22 19:32:58 tp pam_fingerprint-gui[6980]: Return 25 (PAM_IGNORE).
Jun 22 19:33:04 tp lightdm[6980]: pam_unix(lightdm:auth): authentication failure; logname= uid=0 euid=0 tty=:0 ruser= rhost=  user=MY_USER_NAME

New log file: http://pastebin.com/eZmRNj8y
Permalink flipsa 
June 22nd, 2016 7:30pm
More info in case it's helpful in finding the problem:

* A user who does NOT have any fingerprints saved can login with password just fine, so i guess it's not a problem with lightDM-greeter or it's pam config (at least it appears this way)

* I've been using your software since v0.14 (just checked...), and I know that it worked when I first set it up. However, that was years ago, and I've also switched from SLIM to lightDM-greeter (on top of xfce4). So I do not know when it stopped working, if it was after I changed configs or if it got introduced by some update to fingerprint-gui itself :(

Either way, thanks for the program and your time & help, I appreciate it!
Permalink flipsa 
June 22nd, 2016 7:41pm
> Jun 22 19:32:58 tp pam_fingerprint-gui[6980]: Got empty password by keyboard.

This looks like you typed enter only as password. And idea?

W.U.
Permalink Wolfgang Ullrich 
June 22nd, 2016 8:18pm
No clue really.

What happens when trying to login via password:
- My username is usually already pre-selected (due to last login)
- The password field is greyed out and can't be changed at first
- I have to click a button named "Login" below the password field first, so I can enter the password
- Once I click above button, fingerprint-gui animation / logo are hidden and the password field is not greyed out anymore
- When I enter my password, I can see one asterisk (*) per character
- Then i press enter / click the login button and get a "Wrong password" error
- I can now start over again or give up and login via fingerprint without problems

There's also no other logfiles I can think of that have any relevant information. Anything else I can try? I did already re-scan my finger (same one) because i thought it might help, but didn't. Are there maybe any old and now incompatible config files / options from previous versions, as I've been using it for years already?

Again, thanks for trying to help!
Permalink flipsa 
June 22nd, 2016 9:07pm

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