Helper binary that verifies the password of the current user
' unix_chkpwd 'u unix_chkpwd [ . . .]
unix_chkpwd is a helper program for the pam_unix module that verifies the password of the current user . It also checks password and account expiration dates in shadow . It is not intended to be run directly from the command line and logs a security violation if done so .
It is typically installed setuid root or setgid shadow .
The interface of the helper -command line options, and input/output data format are internal to the pam_unix module and it should not be called directly from applications .
Written by Andrew Morgan and other various people .