This plugin redirects all not logged in users to a login page.

Protect your content by allowing only logged in users to access certain pages or posts

This plugin from WPZA provides your website with a shortcode to hide content unless the user is logged in.

Allows media to be uploaded through the Media Library and not be accessible to the public.

Disable the public site functionality, always prompt for a login before showing any content, make WordPress and intranet style site