A small helper application that makes it possible to authenticate OpenVPN against the BSD Authentication System.
BSD Auth is an authentication system originally of BSD/OS origins, similar in purpose to the well-known PAM mechanism, these days only to be found in OpenBSD.
Essentially, it makes it possible for OpenVPN to authenticate users against the OpenBSD system password database.
It is of no use to users of other systems.
The online version of the manual page is available.
The origin home page is here.
Since OpenBSD 4.3, openvpn_bsdauth is available as a package. You are advised not to download and compile this source distribution, but install the appropriate package for your system. This source is not to make your life easy, but to make port maintainer's life easy.