def verify_vote_signature(cls, vote):
"""Verify the signature of a vote
"""
signature = vote.get('signature')
pk_base58 = vote.get('node_pubkey')
if not (type(signature) == str and type(pk_base58) == str):
raise ValueError('Malformed vote: %s' % vote)
public_key = PublicKey(pk_base58)
body = serialize(vote['vote']).encode()
return public_key.verify(body, signature)
def is_signature_valid(self):
"""Check the validity of a Block's signature.
Returns:
bool: Stating the validity of the Block's signature.
"""
block = self.to_dict()['block']
# cc only accepts bytestring messages
block_serialized = serialize(block).encode()
public_key = PublicKey(block['node_pubkey'])
try:
# NOTE: CC throws a `ValueError` on some wrong signatures
# https://github.com/bigchaindb/cryptoconditions/issues/27
return public_key.verify(block_serialized, self.signature)
except (ValueError, AttributeError):
return False
def is_signature_valid(self):
"""Check the validity of a Block's signature.
Returns:
bool: Stating the validity of the Block's signature.
"""
block = self.to_dict()['block']
# cc only accepts bytestring messages
block_serialized = serialize(block).encode()
public_key = PublicKey(block['node_pubkey'])
try:
# NOTE: CC throws a `ValueError` on some wrong signatures
# https://github.com/bigchaindb/cryptoconditions/issues/27
return public_key.verify(block_serialized, self.signature)
except (ValueError, AttributeError):
return False
def test_sign_block(self, b):
from bigchaindb.common.crypto import PrivateKey, PublicKey
from bigchaindb.common.utils import gen_timestamp, serialize
from bigchaindb.models import Block, Transaction
transactions = [Transaction.create([b.me], [([b.me], 1)])]
timestamp = gen_timestamp()
voters = ['Qaaa', 'Qbbb']
expected_block = {
'timestamp': timestamp,
'transactions': [tx.to_dict() for tx in transactions],
'node_pubkey': b.me,
'voters': voters,
}
expected_block_serialized = serialize(expected_block).encode()
expected = PrivateKey(b.me_private).sign(expected_block_serialized)
block = Block(transactions, b.me, timestamp, voters)
block = block.sign(b.me_private)
assert block.signature == expected.decode()
public_key = PublicKey(b.me)
assert public_key.verify(expected_block_serialized, block.signature)
def test_sign_block(self, b, alice):
from bigchaindb.common.crypto import PrivateKey, PublicKey
from bigchaindb.common.utils import gen_timestamp, serialize
from bigchaindb.models import Block, Transaction
transactions = [
Transaction.create([alice.public_key], [([alice.public_key], 1)])
]
timestamp = gen_timestamp()
expected_block = {
'timestamp': timestamp,
'transactions': [tx.to_dict() for tx in transactions],
'node_pubkey': alice.public_key,
}
expected_block_serialized = serialize(expected_block).encode()
expected = PrivateKey(
alice.private_key).sign(expected_block_serialized)
block = Block(transactions, alice.public_key, timestamp)
block = block.sign(alice.private_key)
assert block.signature == expected.decode()
public_key = PublicKey(alice.public_key)
assert public_key.verify(expected_block_serialized, block.signature)
def from_dict(cls, block_body):
"""Transform a Python dictionary to a Block object.
Args:
block_body (dict): A block dictionary to be transformed.
Returns:
:class:`~Block`
Raises:
InvalidHash: If the block's id is not corresponding to its
data.
InvalidSignature: If the block's signature is not corresponding
to it's data or `node_pubkey`.
"""
# TODO: Reuse `is_signature_valid` method here.
block = block_body['block']
block_serialized = serialize(block)
block_id = hash_data(block_serialized)
public_key = PublicKey(block['node_pubkey'])
try:
signature = block_body['signature']
except KeyError:
signature = None
if block_id != block_body['id']:
raise InvalidHash()
if signature is not None:
# NOTE: CC throws a `ValueError` on some wrong signatures
# https://github.com/bigchaindb/cryptoconditions/issues/27
try:
signature_valid = public_key\
.verify(block_serialized.encode(), signature)
except ValueError:
signature_valid = False
if signature_valid is False:
raise InvalidSignature('Invalid block signature')
transactions = [
Transaction.from_dict(tx) for tx in block['transactions']
]
return cls(transactions, block['node_pubkey'], block['timestamp'],
block['voters'], signature)
