def initialize_block(self, block_header): """Do initialization necessary for the consensus to claim a block, this may include initiating voting activates, starting proof of work hash generation, or create a PoET wait timer. Args: block_header (BlockHeader): the BlockHeader to initialize. Returns: True """ # Using the current chain head, we need to create a state view so we # can get our config values. state_view = \ BlockWrapper.state_view_for_block( self._block_cache.block_store.chain_head, self._state_view_factory) settings_view = SettingsView(state_view) self._min_wait_time = settings_view.get_setting( "suomi.consensus.min_wait_time", self._min_wait_time, int) self._max_wait_time = settings_view.get_setting( "suomi.consensus.max_wait_time", self._max_wait_time, int) self._valid_block_publishers = settings_view.get_setting( "suomi.consensus.valid_block_publishers", self._valid_block_publishers, list) block_header.consensus = b"Devmode" self._start_time = time.time() self._wait_time = random.uniform(self._min_wait_time, self._max_wait_time) return True
def _transaction_index_keys(block): blkw = BlockWrapper.wrap(block) keys = [] for batch in blkw.batches: for txn in batch.transactions: keys.append(txn.header_signature.encode()) return keys
def _load_consensus(self, block): """Load the consensus module using the state as of the given block.""" if block is not None: return ConsensusFactory.get_configured_consensus_module( block.header_signature, BlockWrapper.state_view_for_block(block, self._state_view_factory)) return ConsensusFactory.get_consensus_module('genesis')
def add_block(self, block): with self.lock: blkw = BlockWrapper(block) block = self._complete_block(blkw) if block is not None: self.block_cache[block.header_signature] = blkw self._on_block_received(blkw) self._process_incomplete_blocks(block.header_signature) self._incomplete_blocks_length.set_value( len(self._incomplete_blocks))
def on_check_publish_block(self, force=False): """Ask the consensus module if it is time to claim the candidate block if it is then, claim it and tell the world about it. :return: None """ try: with self._lock: if (self._chain_head is not None and self._candidate_block is None and self._pending_batches): self._build_candidate_block(self._chain_head) if self._candidate_block and ( force or self._candidate_block.has_pending_batches()) and \ self._candidate_block.check_publish_block(): pending_batches = [] # will receive the list of batches # that were not added to the block injected_batch_ids = \ self._candidate_block.injected_batch_ids last_batch = self._candidate_block.last_batch block = self._candidate_block.finalize_block( self._identity_signer, pending_batches) self._candidate_block = None # Update the _pending_batches to reflect what we learned. last_batch_index = self._pending_batches.index(last_batch) unsent_batches = \ self._pending_batches[last_batch_index + 1:] self._pending_batches = pending_batches + unsent_batches self._pending_batch_gauge.set_value( len(self._pending_batches)) if block: blkw = BlockWrapper(block) LOGGER.info("Claimed Block: %s", blkw) self._block_sender.send( blkw.block, keep_batches=injected_batch_ids) self._blocks_published_count.inc() # We built our candidate, disable processing until # the chain head is updated. Only set this if # we succeeded. Otherwise try again, this # can happen in cases where txn dependencies # did not validate when building the block. self.on_chain_updated(None) # pylint: disable=broad-except except Exception as exc: LOGGER.critical("on_check_publish_block exception.") LOGGER.exception(exc)
def finalize_block(self, block_header): """Finalize a block to be claimed. Provide any signatures and data updates that need to be applied to the block before it is signed and broadcast to the network. Args: block_header (BlockHeader): The block header for the candidate block that needs to be finalized. Returns: Boolean: True if the candidate block good and should be generated. False if the block should be abandoned. """ # To compute the block hash, we are going to perform a hash using the # previous block ID and the batch IDs contained in the block hasher = hashlib.sha256(block_header.previous_block_id.encode()) for batch_id in block_header.batch_ids: hasher.update(batch_id.encode()) block_hash = hasher.hexdigest() # Using the current chain head, we need to create a state view so we # can create a PoET enclave. state_view = \ BlockWrapper.state_view_for_block( block_wrapper=self._block_cache.block_store.chain_head, state_view_factory=self._state_view_factory) poet_enclave_module = \ factory.PoetEnclaveFactory.get_poet_enclave_module( state_view=state_view, config_dir=self._config_dir, data_dir=self._data_dir) # We need to create a wait certificate for the block and then serialize # that into the block header consensus field. active_key = self._poet_key_state_store.active_key poet_key_state = self._poet_key_state_store[active_key] sealed_signup_data = poet_key_state.sealed_signup_data try: wait_certificate = \ WaitCertificate.create_wait_certificate( poet_enclave_module=poet_enclave_module, sealed_signup_data=sealed_signup_data, wait_timer=self._wait_timer, block_hash=block_hash) block_header.consensus = \ json.dumps(wait_certificate.dump()).encode() except ValueError as ve: LOGGER.error('Failed to create wait certificate: %s', ve) return False LOGGER.debug('Created wait certificate: %s', wait_certificate) return True
def deserialize_block(value): """ Deserialize a byte string into a BlockWrapper Args: value (bytes): the byte string to deserialze Returns: BlockWrapper: a block wrapper instance """ # Block id strings are stored under batch/txn ids for reference. # Only Blocks, not ids or Nones, should be returned by _get_block. block = Block() block.ParseFromString(value) return BlockWrapper(status=BlockStatus.Valid, block=block)
def start(self, on_done): """ Starts the genesis block creation process. Will call the given `on_done` callback on successful completion. Args: on_done (function): a function called on completion Raises: InvalidGenesisStateError: raises this error if a genesis block is unable to be produced, or the resulting block-chain-id saved. """ genesis_file = os.path.join(self._data_dir, 'genesis.batch') try: with open(genesis_file, 'rb') as batch_file: genesis_data = genesis_pb2.GenesisData() genesis_data.ParseFromString(batch_file.read()) LOGGER.info('Producing genesis block from %s', genesis_file) except IOError: raise InvalidGenesisStateError( "Genesis File {} specified, but unreadable".format( genesis_file)) initial_state_root = self._context_manager.get_first_root() genesis_batches = [batch for batch in genesis_data.batches] if genesis_batches: scheduler = SerialScheduler( self._context_manager.get_squash_handler(), initial_state_root, always_persist=True) LOGGER.debug('Adding %s batches', len(genesis_data.batches)) for batch in genesis_data.batches: scheduler.add_batch(batch) self._transaction_executor.execute(scheduler) scheduler.finalize() scheduler.complete(block=True) state_hash = initial_state_root for batch in genesis_batches: result = scheduler.get_batch_execution_result( batch.header_signature) if result is None or not result.is_valid: raise InvalidGenesisStateError( 'Unable to create genesis block, due to batch {}'.format( batch.header_signature)) if result.state_hash is not None: state_hash = result.state_hash LOGGER.debug('Produced state hash %s for genesis block.', state_hash) block_builder = self._generate_genesis_block() block_builder.add_batches(genesis_batches) block_builder.set_state_hash(state_hash) block_publisher = self._get_block_publisher(initial_state_root) if not block_publisher.initialize_block(block_builder.block_header): LOGGER.error('Consensus refused to initialize consensus block.') raise InvalidGenesisConsensusError( 'Consensus refused to initialize genesis block.') if not block_publisher.finalize_block(block_builder.block_header): LOGGER.error('Consensus refused to finalize genesis block.') raise InvalidGenesisConsensusError( 'Consensus refused to finalize genesis block.') self._sign_block(block_builder) block = block_builder.build_block() blkw = BlockWrapper(block=block, status=BlockStatus.Valid) LOGGER.info('Genesis block created: %s', blkw) self._completer.add_block(block) self._block_store.update_chain([blkw]) self._chain_id_manager.save_block_chain_id(block.header_signature) LOGGER.debug('Deleting genesis data.') os.remove(genesis_file) if on_done is not None: on_done()
def _build_candidate_block(self, chain_head): """ Build a candidate block and construct the consensus object to validate it. :param chain_head: The block to build on top of. :return: (BlockBuilder) - The candidate block in a BlockBuilder wrapper. """ state_view = BlockWrapper.state_view_for_block( chain_head, self._state_view_factory) consensus_module = ConsensusFactory.get_configured_consensus_module( chain_head.header_signature, state_view) # using chain_head so so we can use the setting_cache max_batches = int( self._settings_cache.get_setting( 'suomi.publisher.max_batches_per_block', chain_head.state_root_hash, default_value=0)) public_key = self._identity_signer.get_public_key().as_hex() consensus = consensus_module.\ BlockPublisher(block_cache=self._block_cache, state_view_factory=self._state_view_factory, batch_publisher=self._batch_publisher, data_dir=self._data_dir, config_dir=self._config_dir, validator_id=public_key) batch_injectors = [] if self._batch_injector_factory is not None: batch_injectors = self._batch_injector_factory.create_injectors( chain_head.identifier) if batch_injectors: LOGGER.debug("Loaded batch injectors: %s", batch_injectors) block_header = BlockHeader( block_num=chain_head.block_num + 1, previous_block_id=chain_head.header_signature, signer_public_key=public_key) block_builder = BlockBuilder(block_header) if not consensus.initialize_block(block_builder.block_header): if not self._logging_states.consensus_not_ready: self._logging_states.consensus_not_ready = True LOGGER.debug("Consensus not ready to build candidate block.") return None if self._logging_states.consensus_not_ready: self._logging_states.consensus_not_ready = False LOGGER.debug("Consensus is ready to build candidate block.") # create a new scheduler scheduler = self._transaction_executor.create_scheduler( self._squash_handler, chain_head.state_root_hash) # build the TransactionCommitCache committed_txn_cache = TransactionCommitCache( self._block_cache.block_store) self._transaction_executor.execute(scheduler) self._candidate_block = _CandidateBlock( self._block_cache.block_store, consensus, scheduler, committed_txn_cache, block_builder, max_batches, batch_injectors, SettingsView(state_view), public_key) for batch in self._pending_batches: if self._candidate_block.can_add_batch: self._candidate_block.add_batch(batch) else: break
def _get_block(self, key): value = self._block_store.get(key) if value is None: raise KeyError('Block "{}" not found in store'.format(key)) return BlockWrapper.wrap(value)
def _block_num_index_keys(block): blkw = BlockWrapper.wrap(block) # Format the number to a 64bit hex value, for natural ordering return [BlockStore.block_num_to_hex(blkw.block_num).encode()]
def _batch_index_keys(block): blkw = BlockWrapper.wrap(block) return [batch.header_signature.encode() for batch in blkw.batches]
def initialize_block(self, block_header): """Do initialization necessary for the consensus to claim a block, this may include initiating voting activities, starting proof of work hash generation, or create a PoET wait timer. Args: block_header (BlockHeader): The BlockHeader to initialize. Returns: Boolean: True if the candidate block should be built. False if no candidate should be built. """ # If the previous block ID matches our cached one, that means that we # have already determined that even if we initialize the requested # block we would not be able to claim it. So, instead of wasting time # doing all of the checking again, simply short-circuit the failure so # that the validator can go do something more useful. if block_header.previous_block_id == \ PoetBlockPublisher._previous_block_id: return False PoetBlockPublisher._previous_block_id = block_header.previous_block_id # Using the current chain head, we need to create a state view so we # can create a PoET enclave. state_view = \ BlockWrapper.state_view_for_block( block_wrapper=self._block_cache.block_store.chain_head, state_view_factory=self._state_view_factory) poet_enclave_module = \ factory.PoetEnclaveFactory.get_poet_enclave_module( state_view=state_view, config_dir=self._config_dir, data_dir=self._data_dir) # Get our validator registry entry to see what PoET public key # other validators think we are using. validator_registry_view = ValidatorRegistryView(state_view) validator_info = None try: validator_id = block_header.signer_public_key validator_info = \ validator_registry_view.get_validator_info( validator_id=validator_id) except KeyError: pass # If we don't have a validator registry entry, then check the active # key. If we don't have one, then we need to sign up. If we do have # one, then our validator registry entry has not percolated through the # system, so nothing to to but wait. active_poet_public_key = self._poet_key_state_store.active_key if validator_info is None: if active_poet_public_key is None: LOGGER.debug( 'No public key found, so going to register new signup ' 'information') self._register_signup_information( block_header=block_header, poet_enclave_module=poet_enclave_module) else: # Check if we need to give up on this registration attempt try: nonce = self._poet_key_state_store[ active_poet_public_key].signup_nonce except (ValueError, AttributeError): self._poet_key_state_store.active_key = None LOGGER.warning( 'Poet Key State Store had inaccessible or ' 'corrupt active key [%s] clearing ' 'key.', active_poet_public_key) return False self._handle_registration_timeout( block_header=block_header, poet_enclave_module=poet_enclave_module, state_view=state_view, signup_nonce=nonce, poet_public_key=active_poet_public_key) return False # Retrieve the key state corresponding to the PoET public key in our # validator registry entry. poet_key_state = None try: poet_key_state = \ self._poet_key_state_store[ validator_info.signup_info.poet_public_key] except (ValueError, KeyError): pass # If there is no key state associated with the PoET public key that # other validators think we should be using, then we need to create # new signup information as we have no way whatsoever to publish # blocks that other validators will accept. if poet_key_state is None: LOGGER.debug( 'PoET public key %s...%s in validator registry not found in ' 'key state store. Sign up again', validator_info.signup_info.poet_public_key[:8], validator_info.signup_info.poet_public_key[-8:]) self._register_signup_information( block_header=block_header, poet_enclave_module=poet_enclave_module) # We need to put fake information in the key state store for the # PoET public key the other validators think we are using so that # we don't try to keep signing up. However, we are going to mark # that key state store entry as being refreshed so that we will # never actually try to use it. dummy_data = b64encode(b'No sealed signup data').decode('utf-8') self._poet_key_state_store[ validator_info.signup_info.poet_public_key] = \ PoetKeyState( sealed_signup_data=dummy_data, has_been_refreshed=True, signup_nonce='unknown') return False # Check the key state. If it is marked as being refreshed, then we are # waiting until our PoET public key is updated in the validator # registry and therefore we cannot publish any blocks. if poet_key_state.has_been_refreshed: LOGGER.debug( 'PoET public key %s...%s has been refreshed. Wait for new ' 'key to show up in validator registry.', validator_info.signup_info.poet_public_key[:8], validator_info.signup_info.poet_public_key[-8:]) # Check if we need to give up on this registration attempt self._handle_registration_timeout( block_header=block_header, poet_enclave_module=poet_enclave_module, state_view=state_view, signup_nonce=poet_key_state.signup_nonce, poet_public_key=active_poet_public_key) return False # If the PoET public key in the validator registry is not the active # one, then we need to switch the active key in the key state store. if validator_info.signup_info.poet_public_key != \ active_poet_public_key: active_poet_public_key = validator_info.signup_info.poet_public_key self._poet_key_state_store.active_key = active_poet_public_key # Ensure that the enclave is using the appropriate keys try: unsealed_poet_public_key = \ SignupInfo.unseal_signup_data( poet_enclave_module=poet_enclave_module, sealed_signup_data=poet_key_state.sealed_signup_data) except SystemError: # Signup data is unuseable LOGGER.error( 'Could not unseal signup data associated with PPK: %s..%s', active_poet_public_key[:8], active_poet_public_key[-8:]) self._poet_key_state_store.active_key = None return False assert active_poet_public_key == unsealed_poet_public_key LOGGER.debug('Using PoET public key: %s...%s', active_poet_public_key[:8], active_poet_public_key[-8:]) LOGGER.debug('Unseal signup data: %s...%s', poet_key_state.sealed_signup_data[:8], poet_key_state.sealed_signup_data[-8:]) consensus_state = \ ConsensusState.consensus_state_for_block_id( block_id=block_header.previous_block_id, block_cache=self._block_cache, state_view_factory=self._state_view_factory, consensus_state_store=self._consensus_state_store, poet_enclave_module=poet_enclave_module) poet_settings_view = PoetSettingsView(state_view) # If our signup information does not pass the freshness test, then we # know that other validators will reject any blocks we try to claim so # we need to try to sign up again. if consensus_state.validator_signup_was_committed_too_late( validator_info=validator_info, poet_settings_view=poet_settings_view, block_cache=self._block_cache): LOGGER.info( 'Reject building on block %s: Validator signup information ' 'not committed in a timely manner.', block_header.previous_block_id[:8]) self._register_signup_information( block_header=block_header, poet_enclave_module=poet_enclave_module) return False # Using the consensus state for the block upon which we want to # build, check to see how many blocks we have claimed on this chain # with this PoET key. If we have hit the key block claim limit, then # we need to check if the key has been refreshed. if consensus_state.validator_has_claimed_block_limit( validator_info=validator_info, poet_settings_view=poet_settings_view): # Because we have hit the limit, check to see if we have already # submitted a validator registry transaction with new signup # information, and therefore a new PoET public key. If not, then # mark this PoET public key in the store as having been refreshed # and register new signup information. Regardless, since we have # hit the key block claim limit, we won't even bother initializing # a block on this chain as it will be rejected by other # validators. poet_key_state = self._poet_key_state_store[active_poet_public_key] if not poet_key_state.has_been_refreshed: LOGGER.info('Reached block claim limit for key: %s...%s', active_poet_public_key[:8], active_poet_public_key[-8:]) sealed_signup_data = poet_key_state.sealed_signup_data signup_nonce = poet_key_state.signup_nonce self._poet_key_state_store[active_poet_public_key] = \ PoetKeyState( sealed_signup_data=sealed_signup_data, has_been_refreshed=True, signup_nonce=signup_nonce) # Release enclave resources for this identity # This signup will be invalid on all forks that use it, # even if there is a rollback to a point it should be valid. # A more sophisticated policy would be to release signups # only at a block depth where finality probability # is high. SignupInfo.release_signup_data( poet_enclave_module=poet_enclave_module, sealed_signup_data=sealed_signup_data) self._register_signup_information( block_header=block_header, poet_enclave_module=poet_enclave_module) LOGGER.info( 'Reject building on block %s: Validator has reached maximum ' 'number of blocks with key pair.', block_header.previous_block_id[:8]) return False # Verify that we are abiding by the block claim delay (i.e., waiting a # certain number of blocks since our validator registry was added/ # updated). if consensus_state.validator_is_claiming_too_early( validator_info=validator_info, block_number=block_header.block_num, validator_registry_view=validator_registry_view, poet_settings_view=poet_settings_view, block_store=self._block_cache.block_store): LOGGER.info( 'Reject building on block %s: Validator has not waited long ' 'enough since registering validator information.', block_header.previous_block_id[:8]) return False # We need to create a wait timer for the block...this is what we # will check when we are asked if it is time to publish the block poet_key_state = self._poet_key_state_store[active_poet_public_key] sealed_signup_data = poet_key_state.sealed_signup_data previous_certificate_id = \ utils.get_previous_certificate_id( block_header=block_header, block_cache=self._block_cache, poet_enclave_module=poet_enclave_module) wait_timer = \ WaitTimer.create_wait_timer( poet_enclave_module=poet_enclave_module, sealed_signup_data=sealed_signup_data, validator_address=block_header.signer_public_key, previous_certificate_id=previous_certificate_id, consensus_state=consensus_state, poet_settings_view=poet_settings_view) # NOTE - we do the zTest after we create the wait timer because we # need its population estimate to see if this block would be accepted # by other validators based upon the zTest. # Check to see if by chance we were to be able to claim this block # if it would result in us winning more frequently than statistically # expected. If so, then refuse to initialize the block because other # validators will not accept anyway. if consensus_state.validator_is_claiming_too_frequently( validator_info=validator_info, previous_block_id=block_header.previous_block_id, poet_settings_view=poet_settings_view, population_estimate=wait_timer.population_estimate( poet_settings_view=poet_settings_view), block_cache=self._block_cache, poet_enclave_module=poet_enclave_module): LOGGER.info( 'Reject building on block %s: Validator is claiming blocks ' 'too frequently.', block_header.previous_block_id[:8]) return False # At this point, we know that if we are able to claim the block we are # initializing, we will not be prevented from doing so because of PoET # policies. self._wait_timer = wait_timer PoetBlockPublisher._previous_block_id = None LOGGER.debug('Created wait timer: %s', self._wait_timer) return True
def verify_block(self, block_wrapper): """Check that the block received conforms to the consensus rules. Args: block_wrapper (BlockWrapper): The block to validate. Returns: Boolean: True if the Block is valid, False if the block is invalid. """ # Get the state view for the previous block in the chain so we can # create a PoET enclave and validator registry view previous_block = None try: previous_block = \ self._block_cache[block_wrapper.previous_block_id] except KeyError: pass state_view = \ BlockWrapper.state_view_for_block( block_wrapper=previous_block, state_view_factory=self._state_view_factory) poet_enclave_module = \ factory.PoetEnclaveFactory.get_poet_enclave_module( state_view=state_view, config_dir=self._config_dir, data_dir=self._data_dir) validator_registry_view = ValidatorRegistryView(state_view) # Grab the validator info based upon the block signer's public # key try: validator_info = \ validator_registry_view.get_validator_info( block_wrapper.header.signer_public_key) except KeyError: LOGGER.error( 'Block %s rejected: Received block from an unregistered ' 'validator %s...%s', block_wrapper.identifier[:8], block_wrapper.header.signer_public_key[:8], block_wrapper.header.signer_public_key[-8:]) return False LOGGER.debug( 'Block Signer Name=%s, ID=%s...%s, PoET public key=' '%s...%s', validator_info.name, validator_info.id[:8], validator_info.id[-8:], validator_info.signup_info.poet_public_key[:8], validator_info.signup_info.poet_public_key[-8:]) # For the candidate block, reconstitute the wait certificate # and verify that it is valid wait_certificate = \ utils.deserialize_wait_certificate( block=block_wrapper, poet_enclave_module=poet_enclave_module) if wait_certificate is None: LOGGER.error( 'Block %s rejected: Block from validator %s (ID=%s...%s) was ' 'not created by PoET consensus module', block_wrapper.identifier[:8], validator_info.name, validator_info.id[:8], validator_info.id[-8:]) return False # Get the consensus state and PoET configuration view for the block # that is being built upon consensus_state = \ ConsensusState.consensus_state_for_block_id( block_id=block_wrapper.previous_block_id, block_cache=self._block_cache, state_view_factory=self._state_view_factory, consensus_state_store=self._consensus_state_store, poet_enclave_module=poet_enclave_module) poet_settings_view = PoetSettingsView(state_view=state_view) previous_certificate_id = \ utils.get_previous_certificate_id( block_header=block_wrapper.header, block_cache=self._block_cache, poet_enclave_module=poet_enclave_module) try: wait_certificate.check_valid( poet_enclave_module=poet_enclave_module, previous_certificate_id=previous_certificate_id, poet_public_key=validator_info.signup_info.poet_public_key, consensus_state=consensus_state, poet_settings_view=poet_settings_view) except ValueError as error: LOGGER.error( 'Block %s rejected: Wait certificate check failed - %s', block_wrapper.identifier[:8], error) return False # Reject the block if the validator signup information fails the # freshness check. if consensus_state.validator_signup_was_committed_too_late( validator_info=validator_info, poet_settings_view=poet_settings_view, block_cache=self._block_cache): LOGGER.error( 'Block %s rejected: Validator signup information not ' 'committed in a timely manner.', block_wrapper.identifier[:8]) return False # Reject the block if the validator has already claimed the key block # limit for its current PoET key pair. if consensus_state.validator_has_claimed_block_limit( validator_info=validator_info, poet_settings_view=poet_settings_view): LOGGER.error( 'Block %s rejected: Validator has reached maximum number of ' 'blocks with key pair.', block_wrapper.identifier[:8]) return False # Reject the block if the validator has not waited the required number # of blocks between when the block containing its validator registry # transaction was committed to the chain and trying to claim this # block if consensus_state.validator_is_claiming_too_early( validator_info=validator_info, block_number=block_wrapper.block_num, validator_registry_view=validator_registry_view, poet_settings_view=poet_settings_view, block_store=self._block_cache.block_store): LOGGER.error( 'Block %s rejected: Validator has not waited long enough ' 'since registering validator information.', block_wrapper.identifier[:8]) return False # Reject the block if the validator is claiming blocks at a rate that # is more frequent than is statistically allowed (i.e., zTest) if consensus_state.validator_is_claiming_too_frequently( validator_info=validator_info, previous_block_id=block_wrapper.previous_block_id, poet_settings_view=poet_settings_view, population_estimate=wait_certificate.population_estimate( poet_settings_view=poet_settings_view), block_cache=self._block_cache, poet_enclave_module=poet_enclave_module): LOGGER.error( 'Block %s rejected: Validator is claiming blocks too ' 'frequently.', block_wrapper.identifier[:8]) return False return True