How to implement the custom user authentication in orbeon forms

I'm deployed the orbeon war(Version 4.8 CE) file in tomcat and I have configure the persistence layer(Postgres DB). All forms are saved in the PostgresDB. When user hit the tomcat url http://localhost:8080/orbeon with my orbeon then implement the user authentication here.If user is valid then access the form builder otherwise throw error message.

Note user credentials are stored in the user table from the Postgres DB. User table look like.

username password

sree   sree@123

ram   ram@123

Now only authorized user can access the Orbeon Form builder then create/edit/delete forms.

Some one help me how to restrict the user authentication for form builder.

Note: I am using orbeon forms are in liferay portal by using orbeon form runner(orbeon proxy portlet).