import network
import socket
import machine
import utime
import uasyncio as asyncio
import ucryptolib  # Built-in AES encryption library

# Simulated Temperature Sensor (Analog Input on GPIO 34)
sensor_pin = machine.ADC(machine.Pin(34))
sensor_pin.atten(machine.ADC.ATTN_11DB)  # Full range (0-3.3V)

# AES Encryption Key (Must be 16, 24, or 32 bytes)
AES_KEY = b"mysecretkey12345"  # 16-byte key
AES_IV = b"1234567890abcdef"  # 16-byte IV (Initialization Vector)

SSID = "Wokwi-GUEST"  
PASSWORD = ""
SERVER_IP = "127.0.0.1"
SERVER_PORT = 8080

# ------------------------------ ENCRYPTION & DECRYPTION ------------------------------ #
def encrypt_data(data):
    aes = ucryptolib.aes(AES_KEY, 2, AES_IV)  # AES-CBC Mode
    data_bytes = data.encode()  # Convert string to bytes
    pad = 16 - (len(data_bytes) % 16)  # PKCS#7 Padding
    data_bytes += bytes([pad] * pad)  # Append padding
    return aes.encrypt(data_bytes)

def decrypt_data(enc_data):
    aes = ucryptolib.aes(AES_KEY, 2, AES_IV)  # AES-CBC Mode
    decrypted = aes.decrypt(enc_data)  # Decrypt data
    pad = decrypted[-1]  # Get last byte (padding value)
    return decrypted[:-pad].decode()  # Remove padding & return string

# ------------------------------ VICTIM (Client) -------------------------------- #
async def victim_client():
    while True:
        try:
            # Read sensor temperature
            raw_value = sensor_pin.read()
            real_temp = (raw_value / 4095) * 100  # Convert ADC to temperature
            print(f"\n Victim (Client) Read: Temperature={round(real_temp, 2)}°C")

            # Encrypt data before sending
            encrypted_temp = encrypt_data(f"Temperature={round(real_temp, 2)}")
            print(" Encrypted Data Sent:", encrypted_temp)

            # Send to attacker before server
            await attacker_mitm(encrypted_temp)

        except Exception as e:
            print(f" Victim Client Error: {e}")

        await asyncio.sleep(5)  # Simulate delay

# ------------------------------ ATTACKER (MitM - Now Fails to Modify Data) -------------------------------- #
async def attacker_mitm(enc_temp):
    try:
        print("\n Attacker Intercepted Encrypted Data:", enc_temp)

        # Attacker tries to modify the data (Fails due to encryption)
        try:
            modified_data = enc_temp.replace(b"5", b"9")  # Attacker attempts modification
            print(" Attacker Tried to Modify Data:", modified_data)
        except:
            print(" Attacker Failed: Data is Encrypted and Cannot Be Modified")

        # Send encrypted (unchanged) data to the server
        await secure_server_receive(enc_temp)

    except Exception as e:
        print(f"Attacker Error: {e}")

# ------------------------------ SERVER (Receives & Decrypts Data) -------------------------------- #
async def secure_server_receive(enc_temp):
    try:
        print("\n Server Received Encrypted Data:", enc_temp)

        # Decrypt data securely
        decrypted_temp = decrypt_data(enc_temp)
        print(" Server Decrypted Temperature:", decrypted_temp)

    except Exception as e:
        print(f"Secure Server Error: {e}")

# ------------------------------ MAIN EXECUTION -------------------------------- #
async def main():
    await asyncio.gather(
        victim_client(),  # Victim (Client) Task
    )

asyncio.run(main())