title: Dont want to show products to not logged in user in opencart
body: <p>I have opencart installed. Now I want to do something like if user get logged into the system then only he will be able to see the product listing and details page. If he is not logged in then he is not able to view products. </p>
  
  <p>How can I do this? Is there some plugin or extention for that?</p>