利用http协议实现图片窃取

在http协议里有一个referer，用来标示站点来源，大家都遇到这样的情况。转载了一篇博客，图片显示不正常，就和头信息里这个有关



原理：在webserver里面。依据http协议里面refered头信息来推断。来自站外。就转跳到一个非常小的防盗图片里面。

如何实现防盗链？

1 打开apache ，重写模块mod_rewrite

apache配置文件



2 在须要防盗的站点或文件夹，写.htaccess文件并指定防盗规则，自然分析refered信息

是图片，referer与localhost不匹配时进行重写，统一rewrite到一个图片

RewriteEngine On
RewriteCond %{REQUEST_FILENAME} .*\.(jpg|jpeg|gif|png) [NC]
RewriteCond %{HTTP_REFERER} !localhost [NC]
RewriteRule .*  no.png

<?

php
/*
PHP+socket编程　发送HTTP请求

要求能　模拟下载，注冊，登陆,批量发帖
*/

// http请求类的接口
interface Proto {
// 连接url
function conn($url);

//发送get查询
function get();

// 发送post查询
function post();

// 关闭连接
function close();
}

class Http implements Proto {

const CRLF  = "\r\n";

protected $errno = -1;
protected $errstr = '';
protected $response = '';

protected $url = null;
protected $version = 'HTTP/1.1';
protected $fh = null;

protected $line = array();
protected $header = array();
protected $body = array();

public function __construct($url) {
$this->conn($url);
$this->setHeader('Host: ' . $this->url['host']);
}

// 此方法负责写请求行
protected function setLine($method) {
$this->line[0] = $method . ' ' . $this->url['path'] . '?

' .$this->url['query'] . ' '. $this->version;
}

// 此方法负责写头信息
public function setHeader($headerline) {
$this->header[] = $headerline;
}

// 此方法负责写主体信息
protected function setBody($body) {
$this->body[] = http_build_query($body);
}

// 连接url
public function conn($url) {
$this->url = parse_url($url);
//　推断端口
if(!isset($this->url['port'])) {
$this->url['port'] = 80;
}

//　推断query
if(!isset($this->url['query'])) {
$this->url['query'] = '';
}

$this->fh = fsockopen($this->url['host'],$this->url['port'],$this->errno,$this->errstr,3);
}

//构造get请求的数据
public function get() {
$this->setLine('GET');
$this->request();
return $this->response;
}

// 构造post查询的数据
public function post($body = array()) {
$this->setLine('POST');

// 设计content-type
$this->setHeader('Content-type: application/x-www-form-urlencoded');

// 设计主体信息,比GET不一样的地方
$this->setBody($body);

// 计算content-length
$this->setHeader('Content-length: ' . strlen($this->body[0]));

$this->request();

return $this->response;
}

// 真正请求
public function request() {
// 把请求行。头信息，实体信息　放在一个数组里，便于拼接
$req = array_merge($this->line,$this->header,array(''),$this->body,array(''));
//print_r($req);

$req = implode(self::CRLF,$req);
//echo $req; exit;

fwrite($this->fh,$req);

while(!feof($this->fh)) {
$this->response .= fread($this->fh,1024);
}

$this->close(); //　关闭连接
}

// 关闭连接
public function close() {
fclose($this->fh);
}

}

/*
$url = 'http://news.163.com/13/0613/09/9187CJ4C00014JB6.html';

$http = new Http($url);
echo $http->get();
*/
/*
set_time_limit(0);

$url = 'http://liangyue.net.cn/0523/?

';

for($i=1;$i<100;$i++) {
$str = str_shuffle('abcdefghijklmnopqrst0776656');
$tit = substr($str,0,5);
$con = substr($str,6,8);

$http = new Http($url);
$http->post(array('tit'=>$tit,'con'=>$con,'submit'=>'留言'));

echo $tit,'-----------',$con,'<br />';

usleep(2000);
}

*/

实现图片採集

<?php

require('./http.class.php');

$http = new Http('http://localhost/0618/apple.jpg');

$http->setHeader('Referer: http://localhost'); //获得採集结果
$res = $http->get();

file_put_contents('./aa.jpg',substr(strstr($res,"\r\n\r\n"),4));