Integrate GDM and OpenVPN

On server:

use pass auth

--auth-user-pass-verify pam-ldap-plugin

On client:

--auth-user-pass /dev/null
--auth-retry nointeract
--management 127.0.0.1 13579 /etc/ldap.secret
--management-query-passwords

then add in pam.d/auth a program that will connect to client vpn via management interface

telnet 127.0.0.1 13579
 PASSWORD:Need 'Auth' username/password
 username "Auth" foo
 password "Auth" bar
 PASSWORD:Verification Failed: 'Auth' 

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