pure-pcapy3

import pcapy import sys def packet_handler(header, data): # This is a very basic handler. Real-world usage would parse 'data'. print(f"Captured packet! Length: {header.getlen()} bytes") # Try to open 'eth0' or 'en0' (common interface names) # Fallback to an example pcap file if live capture fails or is not desired. interface = 'eth0' # Change to your network interface, e.g., 'wlan0', 'en0' try: # Open live capture on a network interface # interface, snaplen, promiscuous_mode, timeout_ms pc = pcapy.open_live(interface, 1500, True, 100) print(f"Listening on interface: {interface}...") print("Press Ctrl+C to stop.") pc.loop(0, packet_handler) # 0 for infinite loop except pcapy.PcapError as e: print(f"Error opening live capture on {interface}: {e}") print("Trying to open a dummy pcap file instead.") # Fallback to a dummy pcap file for demonstration if live capture fails # (e.g., no permissions, interface not found) try: # For a runnable example without requiring live interface access, you'd usually have a .pcap file. # This example assumes you might have 'test.pcap' or similar. # If not, this part will also fail. # Create a dummy pcap file if it doesn't exist for the example: import os dummy_pcap_path = 'dummy.pcap' if not os.path.exists(dummy_pcap_path): print(f"Warning: '{dummy_pcap_path}' not found. Cannot demonstrate file reading.") else: print(f"Opening pcap file: {dummy_pcap_path}") pc_file = pcapy.open_offline(dummy_pcap_path) pc_file.loop(0, packet_handler) except pcapy.PcapError as e_file: print(f"Error opening pcap file '{dummy_pcap_path}': {e_file}") print("Please ensure you have necessary permissions or a valid pcap file.") except KeyboardInterrupt: print("Capture stopped by user.") except Exception as e: print(f"An unexpected error occurred: {e}")