portforward.py

#!/usr/bin/env python3

import socket
import sys
import threading
import time
import os

target_host = ''
target_port = 443

def clear_screen():
    os.system('cls' if os.name == 'nt' else 'clear')

def print_banner():
    clear_screen()
    print("=" * 40)
    print("      Port Forwarding Utility")
    print("=" * 40)
    print("Forwarding localhost:9999 to " + target_host + ":" + str(target_port))
    print("Press Ctrl+C to disconnect")
    print("=" * 40)
    print("")

def forward_connection(client_socket, target_host, target_port):
    # Connect to the target
    target_socket = socket.socket(socket.AF_INET, socket.SOCK_STREAM)
    try:
        target_socket.connect((target_host, target_port))
    except Exception as e:
        print(f"Error connecting to {target_host}:{target_port} - {str(e)}")
        client_socket.close()
        return

    # Forward data in both directions
    client_to_target = threading.Thread(
        target=forward_data,
        args=(client_socket, target_socket, "client → target")
    )
    
    target_to_client = threading.Thread(
        target=forward_data,
        args=(target_socket, client_socket, "target → client")
    )
    
    client_to_target.start()
    target_to_client.start()

def forward_data(source, destination, direction):
    try:
        while True:
            data = source.recv(4096)
            if not data:
                break
            destination.sendall(data)
    except:
        pass
    finally:
        try:
            source.close()
            destination.close()
        except:
            pass

def main():
    try:
        print_banner()
        
        # Configuration
        local_host = '127.0.0.1'
        local_port = 9999
        
        # Create server socket
        server_socket = socket.socket(socket.AF_INET, socket.SOCK_STREAM)
        server_socket.setsockopt(socket.SOL_SOCKET, socket.SO_REUSEADDR, 1)
        
        try:
            server_socket.bind((local_host, local_port))
        except OSError as e:
            if e.errno == 48 or e.errno == 10048:  # Address already in use
                print(f"Error: Port {local_port} is already in use.")
                print("Please close any application using this port and try again.")
                sys.exit(1)
            raise
            
        server_socket.listen(5)
        print(f"Listening on {local_host}:{local_port}")
        
        connection_count = 0
        
        while True:
            client_socket, client_address = server_socket.accept()
            connection_count += 1
            print(f"New connection from {client_address[0]}:{client_address[1]} (#{connection_count})")
            
            # Start forwarding in a new thread
            proxy_thread = threading.Thread(
                target=forward_connection,
                args=(client_socket, target_host, target_port)
            )
            proxy_thread.daemon = True
            proxy_thread.start()
            
    except KeyboardInterrupt:
        print("\nShutting down...")
    except Exception as e:
        print(f"Error: {str(e)}")
    finally:
        try:
            server_socket.close()
        except:
            pass
        print("Port forwarding stopped.")

if __name__ == "__main__":
    main()