def verify_signature(signed_transaction):
"""Verify the signature of a transaction.
Refer to the documentation of ``bigchaindb.util.verify_signature``
"""
return util.verify_signature(signed_transaction)
def verify_signature(signed_transaction):
"""Verify the signature of a transaction.
Refer to the documentation of ``bigchaindb.util.verify_signature``
"""
return util.verify_signature(signed_transaction)
def test_transform_create(b, user_private_key, user_public_key):
tx = util.create_tx(user_public_key, user_public_key, None, 'CREATE')
tx = util.transform_create(tx)
tx = util.sign_tx(tx, b.me_private)
assert tx['transaction']['current_owner'] == b.me
assert tx['transaction']['new_owner'] == user_public_key
assert util.verify_signature(tx)
def test_transform_create(b, user_sk, user_vk):
from bigchaindb import util
tx = util.create_tx(user_vk, user_vk, None, 'CREATE')
tx = util.transform_create(tx)
tx = util.sign_tx(tx, b.me_private)
assert tx['transaction']['fulfillments'][0]['current_owners'][0] == b.me
assert tx['transaction']['conditions'][0]['new_owners'][0] == user_vk
assert util.verify_signature(tx)
def test_client_can_transfer_assets(mock_requests_post, client):
from bigchaindb import util
tx = client.transfer('a', 123)
assert tx['transaction']['current_owner'] == client.public_key
assert tx['transaction']['new_owner'] == 'a'
assert tx['transaction']['input'] == 123
assert util.verify_signature(tx)
def test_client_can_create_assets(mock_requests_post, client):
from bigchaindb import util
tx = client.create()
# XXX: `CREATE` operations require the node that receives the transaction to modify the data in
# the transaction itself.
# `current_owner` will be overwritten with the public key of the node in the federation
# that will create the real transaction. `signature` will be overwritten with the new signature.
# Note that this scenario is ignored by this test.
assert tx['transaction']['current_owner'] == client.public_key
assert tx['transaction']['new_owner'] == client.public_key
assert tx['transaction']['input'] == None
assert util.verify_signature(tx)
def create_transaction():
"""API endpoint to push transactions to the Federation.
Return:
A JSON string containing the data about the transaction.
"""
bigchain = current_app.config['bigchain']
val = {}
# `force` will try to format the body of the POST request even if the `content-type` header is not
# set to `application/json`
tx = request.get_json(force=True)
if tx['transaction']['operation'] == 'CREATE':
tx = util.transform_create(tx)
tx = util.sign_tx(tx, bigchain.me_private)
if not util.verify_signature(tx):
val['error'] = 'Invalid transaction signature'
val = bigchain.write_transaction(tx)
return flask.jsonify(**tx)
def validate_transaction(bigchain, transaction):
"""Validate a transaction.
Args:
bigchain (Bigchain): an instantiated bigchaindb.Bigchain object.
transaction (dict): transaction to validate.
Returns:
The transaction if the transaction is valid else it raises an
exception describing the reason why the transaction is invalid.
Raises:
OperationError: if the transaction operation is not supported
TransactionDoesNotExist: if the input of the transaction is not found
TransactionOwnerError: if the new transaction is using an input it doesn't own
DoubleSpend: if the transaction is a double spend
InvalidHash: if the hash of the transaction is wrong
InvalidSignature: if the signature of the transaction is wrong
"""
# If the operation is CREATE the transaction should have no inputs and
# should be signed by a federation node
if transaction['transaction']['operation'] == 'CREATE':
if transaction['transaction']['input']:
raise ValueError('A CREATE operation has no inputs')
if transaction['transaction']['current_owner'] not in (
bigchain.federation_nodes + [bigchain.me]):
raise exceptions.OperationError(
'Only federation nodes can use the operation `CREATE`')
else:
# check if the input exists, is owned by the current_owner
if not transaction['transaction']['input']:
raise ValueError(
'Only `CREATE` transactions can have null inputs')
tx_input = bigchain.get_transaction(
transaction['transaction']['input'])
if not tx_input:
raise exceptions.TransactionDoesNotExist(
'input `{}` does not exist in the bigchain'.format(
transaction['transaction']['input']))
if (tx_input['transaction']['new_owner'] !=
transaction['transaction']['current_owner']):
raise exceptions.TransactionOwnerError(
'current_owner `{}` does not own the input `{}`'.format(
transaction['transaction']['current_owner'],
transaction['transaction']['input']))
# check if the input was already spent by a transaction other than
# this one.
spent = bigchain.get_spent(tx_input['id'])
if spent and spent['id'] != transaction['id']:
raise exceptions.DoubleSpend(
'input `{}` was already spent'.format(
transaction['transaction']['input']))
# Check hash of the transaction
calculated_hash = crypto.hash_data(
util.serialize(transaction['transaction']))
if calculated_hash != transaction['id']:
raise exceptions.InvalidHash()
# Check signature
if not util.verify_signature(transaction):
raise exceptions.InvalidSignature()
return transaction
def validate_transaction(bigchain, transaction):
"""Validate a transaction.
Args:
bigchain (Bigchain): an instantiated bigchaindb.Bigchain object.
transaction (dict): transaction to validate.
Returns:
The transaction if the transaction is valid else it raises an
exception describing the reason why the transaction is invalid.
Raises:
OperationError: if the transaction operation is not supported
TransactionDoesNotExist: if the input of the transaction is not found
TransactionOwnerError: if the new transaction is using an input it doesn't own
DoubleSpend: if the transaction is a double spend
InvalidHash: if the hash of the transaction is wrong
InvalidSignature: if the signature of the transaction is wrong
"""
# If the operation is CREATE the transaction should have no inputs and
# should be signed by a federation node
if transaction['transaction']['operation'] == 'CREATE':
if transaction['transaction']['input']:
raise ValueError('A CREATE operation has no inputs')
if transaction['transaction']['current_owner'] not in (
bigchain.federation_nodes + [bigchain.me]):
raise exceptions.OperationError(
'Only federation nodes can use the operation `CREATE`')
else:
# check if the input exists, is owned by the current_owner
if not transaction['transaction']['input']:
raise ValueError(
'Only `CREATE` transactions can have null inputs')
tx_input = bigchain.get_transaction(
transaction['transaction']['input'])
if not tx_input:
raise exceptions.TransactionDoesNotExist(
'input `{}` does not exist in the bigchain'.format(
transaction['transaction']['input']))
if (tx_input['transaction']['new_owner'] !=
transaction['transaction']['current_owner']):
raise exceptions.TransactionOwnerError(
'current_owner `{}` does not own the input `{}`'.format(
transaction['transaction']['current_owner'],
transaction['transaction']['input']))
# check if the input was already spent by a transaction other than
# this one.
spent = bigchain.get_spent(tx_input['id'])
if spent and spent['id'] != transaction['id']:
raise exceptions.DoubleSpend(
'input `{}` was already spent'.format(
transaction['transaction']['input']))
# Check hash of the transaction
calculated_hash = crypto.hash_data(util.serialize(
transaction['transaction']))
if calculated_hash != transaction['id']:
raise exceptions.InvalidHash()
# Check signature
if not util.verify_signature(transaction):
raise exceptions.InvalidSignature()
return transaction
