Restringir mediawiki

  # Requires that a user be registered before they can edit.
  $wgGroupPermissions['*']['edit'] = false;

  # Disable reading by anonymous users
  # $wgGroupPermissions['*']['read'] = false;

  # Prevent new user registrations except by sysops
  $wgGroupPermissions['*']['createaccount'] = false;

Fuente: https://www.mediawiki.org/wiki/Manual:Preventing_access/es#Restrict_access_to_uploaded_files