PHP实现图片防盗链破解操作方法【解决图片防盗链问题/反向代理】

<?php
 class ImgBridge{
  private $water='';
  private $imgUrl=''; 
  private $referer='';
  private $ua='MQQBrowser/26 Mozilla/5.0 (Linux; U; Android 2.3.7; zh-cn; MB200 Build/GRJ22; CyanogenMod-7) AppleWebKit/533.1 (KHTML, like Gecko) Version/4.0 Mobile Safari/533.1';
  private $imgCode='';
  private $imgHeader='';
  private $imgBody='';
  private $imgType='';

  public function __construct($config=array()){
    foreach($config as $key=>$value){
      $this->$key=$value;
    }
  }
  
  public function getImg($imgUrl){
    $this->imgUrl=$imgUrl;
    /** 处理url */
    if(substr($this->imgUrl,0,7)!=='http://' && substr($this->imgUrl,0,8)!=='https://'){
      $this->imgUrl='http://'.$this->imgUrl;
    }
    /** 解析url中的host */
    $url_array=parse_url($this->imgUrl);
    /** 设置referer */
    $this->referer=$this->referer==""?'http://'.$url_array['host']:$this->referer;
    /**开始获取 */
    $this->urlOpen();
    $this->imgBody;
    /**处理错误 */
    if($this->imgCode!=200){
      $this->error(1);
      exit();
    }
    
    /**获取图片格式 */
    preg_match("/Content-Type: image\/(.+?)\n/sim",$this->imgHeader,$result);
    /**看看是不是图片 */
    if(!isset($result[1])){
      $this->error(2);
      exit();
    }else{
      $this->imgType=$result[1];
    }
    /** 输出内容 */
    $this->out();    
  }
  private function out(){
    /** gif 不处理，直接出图 */
    if($this->imgType=='gif'){
      header("Content-Type: image/gif");
      echo $this->imgBody;
      exit();
    }
    header("Content-Type: image/png");
    /** 其他类型的，加水印 */
    $im=imagecreatefromstring($this->imgBody);
    $white = imagecolorallocate($im, 255, 255, 255);
    /*加上水印*/
    if($this->water){
      imagettftext($im, 12, 0, 20, 20, $white, "/fonts/hwxh.ttf", $this->water);      
    }
    imagepng($im);
    
  }
  private function error($err){
    header("Content-Type: image/jpeg");
    $im=imagecreatefromstring(file_get_contents('./default.jpg'));
    imagejpeg($im);
  }

  private function urlOpen()
  {
    $ch = curl_init();
    curl_setopt($ch, CURLOPT_URL, $this->imgUrl);
    curl_setopt($ch, CURLOPT_USERAGENT, $this->ua);
    curl_setopt ($ch,CURLOPT_REFERER,$this->referer);
    curl_setopt($ch, CURLOPT_RETURNTRANSFER, 1);
    curl_setopt($ch, CURLOPT_HEADER, 1);
    /**跳转也要 */
    curl_setopt($ch, CURLOPT_FOLLOWLOCATION, true);
    /** 支持https */
    $opt[CURLOPT_SSL_VERIFYHOST] = 2;
    $opt[CURLOPT_SSL_VERIFYPEER] = FALSE;
    curl_setopt_array($ch, $opt);
    $response = curl_exec($ch);
    $this->imgCode=curl_getinfo($ch, CURLINFO_HTTP_CODE) ;
    if ($this->imgCode == '200') {
      $headerSize = curl_getinfo($ch, CURLINFO_HEADER_SIZE);
      $this->imgHeader = substr($response, 0, $headerSize);
      $this->imgBody = substr($response, $headerSize);
      return ;
    }
    curl_close($ch);
  }

 }
$img=new ImgBridge(array('water'=>''));
$img->getImg(strstr($_SERVER["QUERY_STRING"], "http"));