sniffer-template

Template for building a packet sniffer

This is a ready-to-go base for building your custom packet sniffer.

Steps

• Make sure python3 and scapy are installed
• Copy this script to your script name
• Edit any sections marked "REPLACEME". This will include the trivial "...description='__sniffer_template version '..." and the processpacket function

processpacket

• "processpacket" is handed each sniffed packet one at a time as the object "p".
• Scapy has already identified the headers in the packet. To see what's been identified, run "p.show()"
• The lines that are currently in processpacket are examples, and can be deleted.
• You can:
  1. Print information about each packet
  2. Collect statistics on the entire packet stream
  3. Save some packets to an output file
  4. Do a test (like "if p.haslayer(TCP) and p[TCP].dport == 443:") and process those differently

Features

• Can sniff from an interface, one or more pcap files, or stdin.
• If reading from stdin, it saves all packets to a file and processes that, so it's not processing them live.
• Automatically decompresses gzip and bzip2 compressed pcap files.
• Code is in place to save packets that you feel should be saved

Requirements

Scapy Python3