chkpwd is a program that checks the validity of a users password on a UNIX/PAM-based system.
Currently chkpwd is only tested on Linux, but it should work on a AIX, DragonFly BSD, FreeBSD, HP-UX, Linux, macOS, NetBSD and Solaris operating system too.
I needed a program to verify passwords of users on Linux/UNIX systems using PAM that just returns 0 on success and 1 on error.
You need the PAM development package installed. On Alpine it is named linux-pam-dev, on Debian based systems it is libpam0g-dev.
git clone https://git.xw3.org/hanez/chkpwd.git
cd chkpwd
make
The code only supports verifying passwords for user id 1000 by default. Look at the file chkpwd.h for some compile time options!
Set MAX_UID and MIN_UID at compile time:
gcc -Wall -DMAX_UID=1000 -DMIN_UID=1000 -o chkpwd chkpwd.c -lpam -lpam_misc
WARNING: Install this software with care. chkpwd could easily be used for bruteforcing passwords from local users!
sudo make install
chkpwd is installed to /usr/bin/.
chkpwd.h is installed to /usr/include/ for use in other applications.
sudo make uninstall
chkpwd -h
Usage: chkpwd [-u <username>] [-p <password>] [-v] [-V] [-h]
Options:
-u <username> Set username.
-p <password> Set password.
-v Enable verbose mode.
-V Print program version.
-h Show this help.
You can also use chkpwd even without installing by just running the following command:
./chkpwd
chkpwd returns 0 on success, 1 otherwise.
chkpwd
chkpwd -u hanez
chkpwd -u hanez -p password
echo $?
chkpwd is licensed under the Apache License, Version 2.0.
See LICENSE for details.