pwhistory_helper - Helper binary that transfers password hashes from passwd or shadow to opasswd

       Written by Tomas Mraz based on the code originally in pam_pwhistoryandpam_unix modules.

Linux-PAM                                          07/03/2025                                PWHISTORY_HELPER(8)

pwhistory_helper is a helper program for the pam_pwhistory module that transfers password hashes from
       passwd or shadow file to the opasswd file and checks a password supplied by user against the existing
       hashes in the opasswd file.

       The purpose of the helper is to enable tighter confinement of login and password changing services. The
       helper is thus called only when SELinux is enabled on the system.

       The interface of the helper - command line options, and input/output data format are internal to the
       pam_pwhistory module and it should not be called directly from applications.

       pwhistory_helper - Helper binary that transfers password hashes from passwd or shadow to opasswd

pam_pwhistory(8)

pwhistory_helper [...]