php防盗链代码

<?php
/**
* http://blog.qita.in
*/
$ADMIN = array(
    'defaulturl'=> 'http://blog.qita.in/images/banner-header.gif',  //盗链返回的地址
    'url_1'     => 'http://blog.qita.in/file',
    'url_2'     => 'http://blog.qita.in/file1',
);
$okaysites = array(
  'http://qita.in',
    'http://blog.qita.in',  //白名单
    'http://blog.qita.in/1.html',
);
$reffer = $_SERVER['HTTP_REFERER'];
if ($reffer) {
    $yes = 0;
    while (list($domain, $subarray) = each($okaysites)) {
        if (ereg($subarray, "$reffer")) {
            $yes = 1;
        }
    }
    $theu = 'url_' . $_GET['site'];
  $file = $_GET['file'];
    if ($ADMIN[$theu] and $yes == 1) {
    header("Location: $ADMIN[$theu]/$file");
    } else {
        header("Location: $ADMIN[defaulturl]");
    }
} else {
    header("Location: $ADMIN[defaulturl]");
}
print_r($_SERVER['HTTP_REFERER']);
?>
//该片段来自于http://outofmemory.cn