title: How do I modify a HTTP response packet with winpcap?
body: <p>There are two problems here:</p>
  
  <ol>
  <li>What if content is encoded:gzip...</li>
  <li>Do I also need to change the header part to make the HTTP packet valid(checksums if any?)</li>
  </ol>
  
  <p><strong>UPDATE</strong></p>
  
  <p>Can someone with actual experience elaborate the steps involved?</p>
  
  <p>I'm using <code>winpcap</code> and bpf <code>tcp and src port 80</code> to filter the traffic,so my job lies in this callback function:</p>
  
  <pre><code>void packet_handler(u_char *param, const struct pcap_pkthdr *header, const u_char *pkt_data)
  </code></pre>