def compute_encrypted_message(key: AES128Key,
auth_tag: Nonce,
message: BaseMessage,
authenticated_data: bytes,
) -> bytes:
encrypted_message = aesgcm_encrypt(
key=key,
nonce=auth_tag,
plain_text=message.to_bytes(),
authenticated_data=authenticated_data,
)
return encrypted_message
def compute_encrypted_auth_response(auth_response_key: AES128Key,
id_nonce_signature: bytes,
enr: Optional[ENR],
) -> bytes:
if enr:
plain_text_auth_response = rlp.encode([AUTH_RESPONSE_VERSION, id_nonce_signature, enr])
else:
plain_text_auth_response = rlp.encode([AUTH_RESPONSE_VERSION, id_nonce_signature, []])
encrypted_auth_response = aesgcm_encrypt(
key=auth_response_key,
nonce=ZERO_NONCE,
plain_text=plain_text_auth_response,
authenticated_data=b"",
)
return encrypted_auth_response
def test_decryption_with_wrong_inputs():
key = AES128Key(b"\x00" * 16)
nonce = Nonce(b"\x11" * 12)
plain_text = b"\x33" * 5
aad = b"\x44" * 5
cipher_text = aesgcm_encrypt(key, nonce, plain_text, aad)
assert aesgcm_decrypt(key, nonce, cipher_text, aad) == plain_text
with pytest.raises(ValidationError):
aesgcm_decrypt(b"", nonce, cipher_text, aad)
with pytest.raises(ValidationError):
aesgcm_decrypt(key, b"", cipher_text, aad)
with pytest.raises(DecryptionError):
aesgcm_decrypt(key, nonce, b"", aad)
with pytest.raises(DecryptionError):
aesgcm_decrypt(key, nonce, cipher_text, b"")
def test_roundtrip(key, nonce, plain_text, aad):
cipher_text = aesgcm_encrypt(key, nonce, plain_text, aad)
plain_text_recovered = aesgcm_decrypt(key, nonce, cipher_text, aad)
assert plain_text_recovered == plain_text
def test_encryption_official(key, nonce, plain_text, aad, cipher_text):
encrypted = aesgcm_encrypt(key, nonce, plain_text, aad)
assert encrypted == cipher_text
assert aesgcm_decrypt(key, nonce, cipher_text, aad) == plain_text