伪造客户端IP实例

绝地灬酷狼 2022-08-18 05:59 229阅读 0赞

# 搭建WEB服务  #

创建一个web工程，编写一个简单的servlet获取客户端ip

protected void doGet(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
    		String clientIp = null;
    		clientIp = request.getHeader("X-Forwarded-For");
    		if(clientIp == null || clientIp.length() == 0 || "unknown".equalsIgnoreCase(clientIp)){
    			clientIp = request.getHeader("Proxy-Client-IP");
    		}
    		if(clientIp == null || clientIp.length() == 0 || "unknown".equalsIgnoreCase(clientIp)){
    			clientIp = request.getHeader("WL-Proxy-Client-IP");
    		}
    		if(clientIp == null || clientIp.length() == 0 || "unknown".equalsIgnoreCase(clientIp)){
    			clientIp = request.getHeader("HTTP_CLIENT_IP");
    		}
    		if(clientIp == null || clientIp.length() == 0 || "unknown".equalsIgnoreCase(clientIp)){
    			clientIp = request.getRemoteAddr();
    	        if (clientIp.equals("127.0.0.1")) {    
    	          InetAddress inet = null;
    	          try {
    	            inet = InetAddress.getLocalHost();
    	          } catch (UnknownHostException e) {
    	            e.printStackTrace();
    	          }
    	          clientIp = inet.getHostAddress();
    	        }
    		}
                //如果有多层代理，第一个ip为真实客户端ip
    	    if (clientIp != null && clientIp.length() > 15) {
    	      if (clientIp.indexOf(",") > 0) {
    	    	  clientIp = clientIp.substring(0, clientIp.indexOf(","));
    	      }
    	    }
            logger.info("clientIp = "+clientIp);
    	}

关于请求头中X-FORWARDED-FOR、Proxy-Client-IP、WL-Proxy-Client-IP、HTTP\_CLIENT\_IP信息的含义 [这篇博客][Link 1]写的很详细。

先来测试下这段代码，浏览器请求http://localhost:8080/IPTest/GetIP，看下log4j控制台打印的日志信息

![Center][]

获取到的是本机真实的IP

# 伪造IP #

## 方式一：浏览器插件 ##

以火狐为例，添加一个附加组件Modify Headers，使用它可以更改请求头，达成伪造IP的目的

![Center 1][]

修改方法很简单，选择Header->Select action->Modify,在Header  name输入框输入X-Forwarded-For，Header value输入框输入要伪造的IP，比如212.66.66.123，完了点击Add添加。

![Center 2][]

然后点击Start按钮启动插件，再次在访问WEB服务，查看控制台日志，可见IP伪造成功

![Center 3][]

修改请求头的插件有很多，比如Google浏览器的ModHeader等等。很多网站通过User-Agent头信息来判断用户是通过web还是wap请求来做版本适配的，这些插件的另一种经常用途就是通过修改User-Agent头信息，方便开发人员在PC上做版本适配的开发。

## 方式二：CURL ##

这是通过PHP脚本实现的，代码如下

<?php
    
    
    function fakeIP(){
        $url = "http://localhost:8080/IPTest/GetIP";
        $ip = "100.100.".rand(0,255).".".rand(0,255);//随机生成IP
        echo $ip;
        $headers = array("X-FORWARDED-FOR:$ip");
        $curl = curl_init($url);
        curl_setopt($curl,CURLOPT_HTTPHEADER,$headers);//伪造IP
        //curl_setopt($curl, CURLOPT_RETURNTRANSFER, 1);
        curl_setopt($curl, CURLOPT_USERAGENT,  "Mozilla/5.0");
        $src = curl_exec($curl);
        curl_close($curl);
    }
    
    fakeIP();
    ?>

执行时遇到了以下错误

![Center 4][]

原因是动态链接库未找到，将php.ini文件（php安装目录下）中将extension=php\_curl.dll注释去掉即可，具体可以参考 [这篇博客][Link 2]

再运行一遍

![Center 5][]

查看控制台日志

![Center 6][]

关于PHP cURL的具体用法可以参见 [PHP官网][PHP]

[Link 1]: http://www.cnblogs.com/zhengyun_ustc/archive/2012/09/19/getremoteaddr.html
[Center]: /images/20220731/6667a37c2f884056ac2a242ad4baa685.png
[Center 1]: /images/20220731/7fe5cd4c8cc54eb987568b18e597dde5.png
[Center 2]: /images/20220731/711334dd6cd44d2986b828be018c2782.png
[Center 3]: /images/20220731/8ade5f7fc33a4c3aa6c40be4aa7cb433.png
[Center 4]: /images/20220731/b5e914d842e5433b90f7fbc42b1c4b4e.png
[Link 2]: http://blog.sina.com.cn/s/blog_5339511c0100t14n.html
[Center 5]: /images/20220731/9ffe3075ffc341afb93443c703834209.png
[Center 6]: /images/20220731/4a13489c506d406ca335a01ad56eca8c.png
[PHP]: http://php.net/manual/zh/function.curl-setopt.php