from Crypto.Cipher import AES from Crypto.Hash import CMAC from cryptography.hazmat.primitives.keywrap import aes_key_unwrap def main() -> None: ''' 8B 22 2F FD 1E 76 19 56 59 CF 27 03 89 8C 42 7F - Transient Key 9C E9 34 32 C7 D7 40 16 BA 68 47 63 F8 01 E1 36 - Intermediate Key Derive a KEK (Key Encryption Key) with the TK and the IK AES-Key unwrap zlpriv_protected.dat with the KEK Derivation function uses the TK (given in PR3.3 source) as the AES Key for OMAC1 (CMAC) sign function. Data is IK + a couple of zeros. Oem_Aes_AES128KDFCTR_r8_L128() Data is [i]2 || Label || 0x00 || Context || [L]2 Context is 16 bytes zero. Label = IK i = 1 L = 128 (int) ''' cmac_secret = bytes.fromhex("8B222FFD1E76195659CF2703898C427F") cmac = CMAC.new(cmac_secret, ciphermod=AES) cmac_data = bytes.fromhex('019CE93432C7D74016BA684763F801E13600000000000000000000000000000000000080') cmac.update(cmac_data) KEK = cmac.hexdigest() print(KEK) with open("zlpriv_protected.dat", "rb") as f: zlprotec = f.read() print(aes_key_unwrap(bytes.fromhex(KEK), zlprotec).hex()) if __name__ == '__main__': main()