PHP资源下载防盗链类实例代码

分享一个PHP写的资源下载的类，感兴趣的朋友可以共同探讨研究。

简单的PHP防盗链处理类(重新整理编写成类文件，以便后期改进)；

<?php
/**
 *
 * 防盗链外部资源下载处理类
 *
 * @link
 *
 */
class BurglarDow{
 /**
     * 初始许可下载状态
     * @var    allow
     * @access private
     */
 private $allow = false;
 /**
     * 初始下载地址
     * @var    dowUrl
     * @access private
     */
 private $dowUrl = null;
 /**
     * 初始来路域名
     * @var    RemoteUrl
     * @access private
     */
 private $RemoteUrl = null;
 /**
     * 初始许可资源取用域名列表
     * @var    allowUrl
     * @access private
     */
 private $allowUrl = array();
 /**
     * 初始转跳地址
     * @var    Location
     * @access private
     */
 private $Location = null;
 public function __construct($dowUrl,$Location,array $allowUrl){
  // 初始下载地址
  $this->dowUrl = $dowUrl;
  // 初始许可资源取用域名列表
  $this->allowUrl = $allowUrl;
  // 初始转跳地址
  $this->Location = $Location;
  $this->RemoteUrl = @parse_url($_SERVER['HTTP_REFERER']); // 获取来路域名
  if(!is_array($this->RemoteUrl))
   header("HTTP/1.1 301 Moved Permanently");
   header("Location: ".$this->Location);
  if(isset($this->RemoteUrl['host'])){
   if(in_array($this->RemoteUrl['host'],$this->allowUrl)){ // 判断是否来至许可域名
    $this->allow = true; // 下载许可状态为：真
   }
  }
  unset($this->allowUrl,$this->RemoteUrl); // 释放内存变量
 }
 /**
  * 防盗链资源下载
  * @access public
  * @return mixed
  */
 public function dow(){
  $FileInfo = get_headers($this->dowUrl,1); // 获取远程文件头部信息
  if(true === $this->allow){ // 判断是否许可下载资源
   //判断配置文件是否存在
   if(is_file('Config.ini')){
    $FileCon = parse_ini_file('Config.ini');
   }else{
    $FileName = basename($FileInfo['Content-Location']);
    $FileConStr = "FileName  = {$FileName}\r\nFileUrl   = {$FileInfo['Content-Location']}\r\nFileSize   = {$FileInfo['Content-Length']}";
    $handle = fopen ('Config.ini', "wb");// Config.ini文件不存在则创建文件
    if (fwrite ($handle, $FileConStr) == FALSE) { // 数据写入文件
     echo "File creation failed ...";
    }
    fclose ($handle); // 关闭一个已打开的文件指针
    $FileCon = parse_ini_file('Config.ini');
   }
   if(!empty($$this->dowUrl)){
    $fp = @fopen($$this->dowUrl, "rb"); // 二进制模式读取文件
    if (!$fp)
      exit("Download a mistake.\n\n");
    // 输出远程资源
    header("Content-type:text/html;charset=utf-8");
    header('Content-Description: File Transfer');
    header('Content-Type: application/octet-stream');
    header('Content-Disposition: attachment; filename='.$FileCon['FileName']);
    header("Accept-Ranges: bytes");
    header('Content-Transfer-Encoding: binary');
    header('Expires: 0');
    header('Cache-Control:must-revalidate,post-check=0,pre-check=0');
    header('Pragma: public');
    header('Content-Length: '.$FileCon['FileSize']);
    while (!feof($fp)){
     set_time_limit(0); // 设置文件最长执行时间
     echo fread($fp, 1024); // 输出文件
     flush(); // 输出缓冲
     ob_flush(); // 输出缓冲区中的内容
    }
    fclose($fp);
   }else{
    header("HTTP/1.1 404 Not Found");
   }
  }else{
   header("HTTP/1.1 301 Moved Permanently");
   header("Location: ".$this->Location);
  }
 }
}
// 远程资源地址
$dowUrl = '';
// 转跳地址
$Location = '';
// 许可来路域名列表
$allowUrl = array(
 'jbxue.com',
);
$BurglarDow = new BurglarDow($dowUrl,$Location,$allowUrl);
$BurglarDow -> dow();