def get_bytes(self, for_signing: bool=False):
result = []
result.append(struct.pack(">B", self._type)) # byte
result.append(struct.pack(">Q", self._timestamp)) # Long
if self._type in [self.type_coin_generation, self.type_seed, self.type_standard, self.type_cycle]:
result.append(struct.pack(">Q", self._amount)) # Long
result.append(self._receiver_identifier)
elif self._type == self.type_cycle_signature:
result.append(self._sender_identifier)
result.append(struct.pack(">B", self._cycle_transaction_vote)) # byte
result.append(self._cycle_transaction_signature)
if not for_signing:
result.append(self._signature)
if self._type in [self.type_seed, self.type_standard, self.type_cycle]:
if for_signing:
result.append(self._previous_block_hash)
else:
result.append(struct.pack(">Q", self._previous_hash_height)) # Long
result.append(self._sender_identifier)
# For serializing, we use the raw sender data with a length specifier. For signing, we use the double-
# SHA-256 of the user data. This will allow us to remove inappropriate or illegal metadata from the
# blockchain at a later date by replacing it with its double-SHA-256 without compromising the signature
# integrity.
if for_signing:
result.append(HashUtil.double_sha256(self._sender_data))
else:
result.append(struct.pack(">B", len(self._sender_data))) # byte
result.append(self._sender_data)
if not for_signing:
result.append(self._signature)
# For cycle transactions, order the signatures by verifier identifier. In the v1 blockchain, the
# cycleSignatures field is used. In the v2 blockchain, the cycleSignatureTransactions field is used.
if self._type == self.type_cycle:
if self.cycle_signatures:
result.append(struct.pack(">I", len(self._cycle_signatures))) # int, 4
for identifier, signature in sorted(self._cycle_signatures, key=lambda x: x[0]):
result.append(identifier)
result.append(signature)
else:
result.append(struct.pack(">I", len(self._cycle_signature_transactions))) # int, 4
for identifier, transaction in sorted(self._cycle_signature_transactions, key=lambda x: x[0]):
result.append(struct.pack(">Q", transaction.timestamp)) # Long
result.append(transaction.sender_identifier);
result.append(transaction.cycle_transaction_vote);
result.append(transaction.signature);
return b''.join(result)
def test_double_2(verbose=False):
hello = b''
hex = HashUtil.double_sha256(hello).hex()
if verbose:
print("hex", hex)
assert hex == '5df6e0e2761359d30a8275058e299fcc0381534545f55cf43e41983f5d4c9456'
def test_double_1(verbose=False):
hello = b"hello"
hex = HashUtil.double_sha256(hello).hex()
if verbose:
print("hex", hex)
assert hex == '9595c9df90075148eb06860365df33584b75bff782a510c6cd4883a419833d50'
def test_single_2(verbose=False):
hello = b''
hex = HashUtil.single_sha256(hello).hex()
if verbose:
print("hex", hex)
assert hex == 'e3b0c44298fc1c149afbf4c8996fb92427ae41e4649b934ca495991b7852b855'
def test_single_1(verbose=False):
hello = b"hello"
hex = HashUtil.single_sha256(hello).hex()
if verbose:
print("hex", hex)
assert hex == '2cf24dba5fb0a30e26e83b2ac5b9e29e1b161e5c1fa7425e73043362938b9824'
def get_hash(self) -> bytes:
return HashUtil.double_sha256(self.get_bytes())
def get_hash(self) -> bytes:
return HashUtil.double_sha256(self._verifier_signature)