Port Knocking Script

This Python script performs port knocking, a method to access closed network ports by sending specific sequences of connection attempts to predefined ports. It supports knocking on both private and public IP addresses and checks if a target port opens after sending the sequences.

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Features

• Comprehensive Port Knocking Sequences: Contains a list of common port knock sequences.
• Private/Public IP Detection: Adjusts the knocking protocol based on the IP type.
• Port Status Check: Verifies if the target port opens after sending knock sequences.
• Customizable: Accepts target IP and port as command-line arguments.
• Uses scapy for Packet Crafting: Creates and sends custom TCP packets.

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Dependencies

The script requires the following Python libraries:

• socket (standard library)
• time (standard library)
• ipaddress (standard library)
• argparse (standard library)
• scapy

Install scapy using pip if not already installed:

pip install scapy

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Usage

Command-Line Arguments

• target_ip (required): The IP address to knock on.
• target_port (required): The port to check after knocking.

Example

python port_knocking.py 192.168.1.100 22

This example knocks on the private IP 192.168.1.100 and checks if port 22 (SSH) is open.

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How It Works

1. IP Type Detection:

   • Determines if the target IP is private or public.
   • Uses private or public IP-specific packet crafting.

2. Knocking Sequence:

   • Sends predefined sequences of TCP SYN packets to the target.
   • Delays 200ms between packets to simulate real-world scenarios.

3. Port Status Check:

   • Uses a TCP socket to verify if the target port is open.

4. Feedback:

   • Outputs the success or failure of each knock sequence in real-time.

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Code Structure

Functions

• is_private_ip(ip)

  • Checks if the provided IP is private using the ipaddress module.

• send_knock_sequence(target_ip, sequence, is_private)

  • Sends a port knock sequence using TCP SYN packets.
  • Uses broadcast packets for public IPs.

• is_port_open(target_ip, port)

  • Checks if a specific port is open using a TCP socket.

• main(target_ip, target_port)

  • Orchestrates the entire knocking process:
    • Detects IP type.
    • Iterates through port knock sequences.
    • Verifies port status after each sequence.

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Predefined Knock Sequences

The script includes common sequences used in port knocking:

• [7000, 8000, 9000]
• [12345, 23456, 34567]
• [22, 80, 443]
• [2, 3, 5, 7, 11]
• And more...

These sequences can be easily extended or modified in the COMMON_SEQUENCES list.

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Disclaimer

This script is for educational and authorized testing purposes only. Unauthorized use on networks or systems is illegal and unethical.

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