Binary package “pwauth” in ubuntu xenial

authenticator for mod_authnz_external and the Apache HTTP Daemon

 Pwauth is an authenticator designed to be used with
 mod_auth_external or mod_authnz_external and the Apache
 HTTP Daemon to support reasonably secure web
 authentication out of the system password database on most
 versions of Unix. Particulary - secure authentication
 against PAM.