A Python Script to Wake-On-Lan

wol.py

"""
Wake-on-LAN (WoL) Utility

This script sends a Wake-on-LAN magic packet to a target network device,
allowing it to be powered on remotely. The magic packet is constructed
using the device's MAC address and sent via UDP broadcast to the specified
IP address and port.

Features:
- Validates MAC address, IP address, and port inputs.
- Supports multiple MAC address formats (e.g., 00:11:22:33:44:55,
  00-11-22-33-44-55, or 001122334455).
- Uses UDP broadcast to send the magic packet.
- Provides command-line interface with examples and error handling.

Usage:
    Run the script with required arguments:
    python wol.py --mac <MAC_ADDRESS> [--ip <BROADCAST_IP>] [--port <PORT>]

Dependencies:
    - Python 3.x
    - Standard libraries: socket, argparse, sys

Exit Codes:
    0: Success
    1: Validation or network error
    130: Aborted by user (Ctrl+C)
"""

import socket
import argparse
import sys

def validate_mac(mac_address):
    """Validate and normalize MAC address to 12 hex digits."""
    mac_clean = mac_address.replace(':', '').replace('-', '').replace('.', '').replace(' ', '').lower()

    if len(mac_clean) != 12:
        raise ValueError(f"MAC address must be 12 hex digits, got {len(mac_clean)}")

    if not all(c in '0123456789abcdef' for c in mac_clean):
        raise ValueError("MAC address contains invalid characters")

    return mac_clean

def validate_ip(ip_address):
    """Validate IP address format."""
    try:
        socket.inet_aton(ip_address)
    except socket.error:
        raise ValueError(f"Invalid IP address: {ip_address}")

def validate_port(port):
    """Validate port number."""
    if not 0 < port < 65536:
        raise ValueError(f"Port must be between 1 and 65535, got {port}")

def wake_on_lan(mac_address, ip_address, port):
    """Send Wake-on-LAN magic packet to target MAC address."""
    mac_clean = validate_mac(mac_address)
    validate_ip(ip_address)
    validate_port(port)

    mac_bytes = bytes.fromhex(mac_clean)
    magic_packet = b'\xff' * 6 + mac_bytes * 16

    try:
        with socket.socket(socket.AF_INET, socket.SOCK_DGRAM) as sock:
            sock.setsockopt(socket.SOL_SOCKET, socket.SO_BROADCAST, 1)
            bytes_sent = sock.sendto(magic_packet, (ip_address, port))

        print(f"Sent {bytes_sent} bytes to {mac_address} via {ip_address}:{port}")
        return True
    except socket.error as e:
        print(f"Network error: {e}", file=sys.stderr)
        return False

def main():
    parser = argparse.ArgumentParser(
        description='Send Wake-on-LAN magic packet to wake a network device',
        formatter_class=argparse.RawDescriptionHelpFormatter,
        epilog="""
Examples:
  %(prog)s --mac 00:11:22:33:44:55
  %(prog)s --mac 00-11-22-33-44-55 --ip 192.168.1.255
  %(prog)s --mac 001122334455 --ip 10.0.0.255 --port 7
        """
    )
    parser.add_argument('--mac', required=True,
                       help='MAC address (formats: 00:11:22:33:44:55, 00-11-22-33-44-55, or 001122334455)')
    parser.add_argument('--ip', default='255.255.255.255',
                       help='Broadcast IP address (default: 255.255.255.255)')
    parser.add_argument('--port', type=int, default=9,
                       help='UDP port (default: 9, alternative: 7)')

    args = parser.parse_args()

    try:
        success = wake_on_lan(args.mac, args.ip, args.port)
    except ValueError as e:
        print(f"Validation error: {e}", file=sys.stderr)
        sys.exit(1)
    except KeyboardInterrupt:
        print("\nAborted", file=sys.stderr)
        sys.exit(130)
    else:
        sys.exit(0 if success else 1)

if __name__ == "__main__":
    main()