import base64
import random
from Crypto.Cipher import AES

KEY = random.randbytes(16)
# KEY =b'\xaab\xa65z"\xac\xb1,a\xff1\xdb6}\xb0' # The key should match the server's key
IV = b"\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00"  # The IV can be random

def pkcs7(message: bytes, block_size: int = 16) -> bytes:
    gap_size = block_size - (len(message) % block_size)
    return message + bytes([gap_size] * gap_size)


def cbc_mac(message: bytes, iv: bytes, key: bytes) -> bytes:
    cipher = AES.new(key, AES.MODE_CBC, iv)
    message = pkcs7(message)
    last_block = cipher.encrypt(message)[-16:]
    return last_block

# Craft the message
message = b"type=recrets&number=1337"

# Calculate the MAC
mac = cbc_mac(message, IV, KEY)

# Base64 encode the message, IV, and MAC
encoded_message = base64.b64encode(message).decode('utf-8')
encoded_iv = base64.b64encode(IV).decode('utf-8')
encoded_mac = base64.b64encode(cbc_mac(message, IV,KEY)).decode('utf-8')

# Final request to send
final_message = f"{encoded_message};{encoded_iv};{encoded_mac}"

print(final_message)

# MAC verification failed: expected afb7f5f307ea507b631d964e089a820a, got a0b0b48844a7deaf9d917a5f11ae0359