/interface ethernet switch rule
dst-port=5678 protocol=udp vlan-id=11 \
mirror=ether2 new-vlan-id=12

# Use Python 3.11 slim as the base image
FROM python:3.11-slim

# Set the working directory in the container
WORKDIR /app

# Install required system dependencies
RUN apt-get update && apt-get install -y libpcap-dev tcpdump && apt-get clean

# Copy the Python script to the container
COPY udp_forwarder_bidirectional.py /app/

# Install Python dependencies (Scapy)
RUN pip install scapy

# Define the entry point
CMD ["python", "udp_forwarder_bidirectional.py"]

version: "3.9"  # Define the compose file version

services:
  mndp-reflector:
    build:
      context: .  # Current directory containing Dockerfile and scripts
      dockerfile: Dockerfile
    container_name: vlan101-vlan102-mndp-reflector
    restart: always
    cap_add:
      - NET_ADMIN  # Allow the container to manage network interfaces
      - NET_RAW    # Allow raw network packet manipulation
    command: python3 /app/udp_forwarder_bidirectional.py  # Start the Python script
    networks:
      vlan101:
        ipv4_address: 10.88.101.2  # Specific IP for VLAN101
      vlan102:
        ipv4_address: 10.88.102.2  # Specific IP for VLAN102

networks:
  vlan101:
    external: true  # Use the existing vlan101 network
  vlan102:
    external: true  # Use the existing vlan102 network

from scapy.all import Ether, IP, UDP, sendp, Raw
import socket
import threading

# Configuration from environment variables
import os
SOURCE_INTERFACE_VLAN101 = os.getenv("SOURCE_INTERFACE_VLAN101", "eth0")
TARGET_INTERFACE_VLAN102 = os.getenv("TARGET_INTERFACE_VLAN102", "eth1")
SOURCE_INTERFACE_VLAN102 = os.getenv("SOURCE_INTERFACE_VLAN102", "eth1")
TARGET_INTERFACE_VLAN101 = os.getenv("TARGET_INTERFACE_VLAN101", "eth0")
SOURCE_PORT = int(os.getenv("SOURCE_PORT", 5678))
TARGET_PORT = int(os.getenv("TARGET_PORT", 5678))
BROADCAST_MAC = "ff:ff:ff:ff:ff:ff"

# Function to forward traffic from VLAN101 to VLAN102
def forward_vlan101_to_vlan102():
    sock = socket.socket(socket.AF_INET, socket.SOCK_DGRAM)
    sock.bind(("", SOURCE_PORT))
    print(f"Listening on {SOURCE_INTERFACE_VLAN101}, forwarding to {TARGET_INTERFACE_VLAN102}...")

    while True:
        try:
            data, addr = sock.recvfrom(2048)
            print(f"[VLAN101 -> VLAN102] Received from {addr}: {data}")

            # Check if source port matches
            if addr[1] != SOURCE_PORT:
                print(f"[VLAN101 -> VLAN102] Ignored packet from port {addr[1]}")
                continue

            ether = Ether(dst=BROADCAST_MAC)
            ip = IP(src=addr[0], dst="255.255.255.255")  # Keep source IP, set destination as broadcast
            udp = UDP(sport=SOURCE_PORT, dport=TARGET_PORT)
            payload = Raw(load=data)

            sendp(ether / ip / udp / payload, iface=TARGET_INTERFACE_VLAN102, verbose=False)
            print(f"[VLAN101 -> VLAN102] Sent to broadcast on {TARGET_INTERFACE_VLAN102}")
        except Exception as e:
            print(f"[VLAN101 -> VLAN102] Error: {e}")

# Function to forward traffic from VLAN102 to VLAN101
def forward_vlan102_to_vlan101_raw():
    sock = socket.socket(socket.AF_PACKET, socket.SOCK_RAW, socket.htons(3))
    sock.bind((SOURCE_INTERFACE_VLAN102, 0))
    print(f"Listening on {SOURCE_INTERFACE_VLAN102}, forwarding to {TARGET_INTERFACE_VLAN101}...")

    while True:
        try:
            packet = sock.recv(2048)
            ether = Ether(packet)

            # Filter only UDP packets with the desired ports
            if UDP in ether and ether[UDP].sport == SOURCE_PORT and ether[UDP].dport == TARGET_PORT:
                sendp(ether, iface=TARGET_INTERFACE_VLAN101, verbose=False)
                print(f"[VLAN102 -> VLAN101] Forwarded UDP packet: {ether.summary()}")
            else:
                print(f"[VLAN102 -> VLAN101] Ignored non-matching packet")
        except Exception as e:
            print(f"[VLAN102 -> VLAN101] Error: {e}")

# Start forwarding threads
thread_vlan101_to_vlan102 = threading.Thread(target=forward_vlan101_to_vlan102, daemon=True)
thread_vlan102_to_vlan101 = threading.Thread(target=forward_vlan102_to_vlan101_raw, daemon=True)

thread_vlan101_to_vlan102.start()
thread_vlan102_to_vlan101.start()

thread_vlan101_to_vlan102.join()
thread_vlan102_to_vlan101.join()