security-misc/usr/bin/faillock-user

#!/bin/bash

## Copyright (C) 2022 - 2022 ENCRYPTED SUPPORT LP <adrelanos@whonix.org>
## See the file COPYING for copying conditions.

true "$0: START PHASE 1"

if test -f /etc/pam-info-debug || test -f /usr/local/etc/pam-info-debug ; then
   set -x
   exec 5>&1 1>> ~/pam-info-debug.txt
   exec 6>&2 2>> ~/pam-info-debug.txt
fi

true "$0: START PHASE 2"

if ! command -v "/usr/sbin/faillock" &>/dev/null; then
   true "$0: ERROR: The faillock program is unavailable, exiting."
   exit 2
fi

## Debugging.
who_ami="$(whoami)"
true "$0: who_ami: $who_ami"
true "$0: PAM_USER: $PAM_USER"
true "$0: SUDO_USER: $SUDO_USER"

if [ "$SUDO_USER" = "" ]; then
   user_to_check="$who_ami"
else
   user_to_check="$SUDO_USER"
fi

if [ "$(id -u)" = "0" ]; then
   faillock_program="/usr/sbin/faillock"
else
   ## as user "user"
   ## /usr/sbin/faillock -u user
   ## faillock: Error opening /var/log/tallylog for update: Permission denied
   ## /usr/sbin/faillock: Authentication error
   ##
   ## xscreensaver runs as user "user", therefore pam_faillock cannot function.
   ## xscreensaver has its own failed login counter.
   ##
   ## https://askubuntu.com/questions/983183/how-lock-the-unlock-screen-after-wrong-password-attempts
   ##
   ## https://www.whonix.org/pipermail/whonix-devel/2019-September/001439.html
   #true "$0: not started as root, exiting."
   #exit 0

   faillock_program="sudo --non-interactive /usr/sbin/faillock"
fi

$faillock_program --user "$user_to_check"

exit $?