Arch Linux

theonlylawislove

Member

Registered: 2015-01-05

Posts: 38

PAM won't authenticate users. i3lock and plasma lock screens fail

I can log into my machine, start an xsession, etc, but if I use a lock screen, it will say the password was invalid.

unix_chkpwd[29535]: check pass; user unknown
unix_chkpwd[29536]: check pass; user unknown
unix_chkpwd[29536]: password check failed for user (pknopf)
i3lock[29504]: pam_unix(i3lock:auth): authentication failure; logname= uid=1000 euid=1000 tty=:0 ruser= rhost= user=pknopf
unix_chkpwd[29537]: check pass; user unknown
unix_chkpwd[29538]: check pass; user unknown
unix_chkpwd[29538]: password check failed for user (pknopf)

Happens in i3 with i3lock, or with the screen lock in KDE.

I haven't customized PAM in any way since my installation.

Last edited by theonlylawislove (2018-02-06 23:04:44)

theonlylawislove

Member

Registered: 2015-01-05

Posts: 38

Re: PAM won't authenticate users. i3lock and plasma lock screens fail

It won't work with pamtester either.

> pamtester auth pknopf authenticate
Password:
pamtester: Authentication failure

theonlylawislove

Member

Registered: 2015-01-05

Posts: 38

Re: PAM won't authenticate users. i3lock and plasma lock screens fail

Ok, so, if I run pamtester as root, I can check the authentication for any user. That works.

So, I tried running i3lock as sudo. I can now unlock it with the root password.

However, if I run i3lock as normal user (1000), I can't use user password to unlock.

theonlylawislove

Member

Registered: 2015-01-05

Posts: 38

Re: PAM won't authenticate users. i3lock and plasma lock screens fail

Here is the pam configuration for the i3lock.

#
# PAM configuration file for the i3lock screen locker. By default, it includes
# the 'system-auth' configuration file (see /etc/pam.d/login)
#
auth include system-auth

caillou

Member

Registered: 2018-05-23

Posts: 1

Re: PAM won't authenticate users. i3lock and plasma lock screens fail

@theonlylawislove did you find a solution for this porblem?

I am setting up arch for the first time and this is the first problem I ran into that I can not seem to solve myself. I installed

pamtester

from AUR with the same result.

UPDATE: I found your question and the answer on unix.stackexchange.com/questions/422411. This solved my problem too. Now the question remains, why and how this happened.

Last edited by caillou (2018-05-23 09:57:24)