nixpkgs/etc/pam.d/common

@isLDAPEnabled@  auth     sufficient     @pam_ldap@/lib/security/pam_ldap.so 
auth     sufficient     @pam_unix2@/lib/security/pam_unix2.so
auth     required       pam_deny.so

@isLDAPEnabled@  account  optional       @pam_ldap@/lib/security/pam_ldap.so 
account  required       @pam_unix2@/lib/security/pam_unix2.so

@isLDAPEnabled@  password sufficient     @pam_ldap@/lib/security/pam_ldap.so 
password sufficient     @pam_unix2@/lib/security/pam_unix2.so nullok

@isLDAPEnabled@  session  optional       @pam_ldap@/lib/security/pam_ldap.so 
session  required       @pam_unix2@/lib/security/pam_unix2.so
session  optional       pam_env.so envfile=@envConf@