class UpdateStateResponse(ContractResponse):
def __init__(self, request, response, **kwargs):
super().__init__(request, response, **kwargs)
self.state_changed = True
self.request_number = request.request_number
self.operation = 'update'
self.signature = response['Signature']
# we have another mismatch between the field names in the enclave
# and the field names expected in the transaction; this needs to
# be fixed at some point
for dependency in response['Dependencies']:
contract_id = dependency['ContractID']
state_hash = dependency['StateHash']
self.dependencies.append({
'contract_id': contract_id,
'state_hash': state_hash
})
# save the information we will need for the transaction
state_hash_b64 = response['StateHash']
self.new_state_hash = crypto.base64_to_byte_array(state_hash_b64)
self.old_state_hash = ContractState.compute_state_hash(
request.contract_state.raw_state)
message = self.serialize_for_signing()
if not self.verify_enclave_signature(message, request.enclave_keys):
raise Exception('failed to verify enclave signature')
self.raw_state = self.enclave_service.get_block(state_hash_b64)
self.new_state_object = ContractState(self.contract_id, self.raw_state)
self.new_state_object.pull_state_from_eservice(self.enclave_service)
# compute ids of blocks in the change set (used for replication)
self.new_state_object.compute_new_block_ids(
request.contract_state.component_block_ids)
self.replication_params = request.replication_params
# -------------------------------------------------------
def serialize_for_signing(self):
"""serialize the response for enclave signature verification"""
message = super().serialize_for_signing()
message += self.old_state_hash
message += self.new_state_hash
for dependency in self.dependencies:
message += crypto.string_to_byte_array(dependency['contract_id'])
message += crypto.string_to_byte_array(dependency['state_hash'])
return message
class InitializeStateResponse(ContractResponse):
def __init__(self, request, response, **kwargs):
super().__init__(request, response, **kwargs)
self.state_changed = True
self.request_number = request.request_number
self.operation = 'initialize'
self.metadata_hash = crypto.base64_to_byte_array(
response['MetadataHash'])
self.signature = response['Signature']
# save the information we will need for the transaction
state_hash_b64 = response['StateHash']
self.new_state_hash = crypto.base64_to_byte_array(state_hash_b64)
message = self.serialize_for_signing()
if not self.verify_enclave_signature(message, request.enclave_keys):
raise InvocationException('failed to verify enclave signature')
self.raw_state = self.enclave_service.get_block(state_hash_b64)
self.new_state_object = ContractState(self.contract_id, self.raw_state)
self.new_state_object.pull_state_from_eservice(self.enclave_service)
# compute ids of blocks in the change set (used for replication)
self.new_state_object.compute_new_block_ids(
request.contract_state.component_block_ids)
self.replication_params = request.replication_params
# -------------------------------------------------------
def serialize_for_signing(self):
"""serialize the response for enclave signature verification"""
message = super().serialize_for_signing()
message += crypto.string_to_byte_array(self.creator_id)
message += self.metadata_hash
message += self.new_state_hash
return message
