Need to download uploaded binary file

If your webserver is Apache, you’ll need to tell apache what kind of mime type your file is, so Apache knows how to handle it. You should be able to use the “application/octet-stream” mime type in your .htaccess, in order for Apache to force a download. Learn more here: http://www.htaccess-guide.com/adding-mime-types/ (see the 3rd paragraph, starting with “A Handy Trick”).

Regarding the media library — by default, wordpress blocks most types of files from being uploaded. To allow more file types, you’ll need to filter the allowed types. Add this to your theme’s functions.php:

<?php
function custom_upload_mimes($mime_types) 
{
    $mime_types['war'] = 'application/octet-stream';
    return $mime_types;
}
add_filter('upload_mimes', 'custom_upload_mimes');
?>