So far from what I understand it gets given a username/password pair, it then searches the LDAP for the username and tries to log into the LDAP using the distinguished name and the password pair, if it succeeds then the authentication is successful, if not then it isn't.
So how does this match up to a schema?
Is there an absolutely minimal schema that PAM requires (for example: something that just contains dn and password) or is it configured to search through a particular field name for a match on the username and then compare the password to one in another specified field?