def test_get_validators(self):
"""Given a state view with multiple validators, and the 'validator_map'
entry, verify that get_validators returns the list of just
ValidatorInfo instances.
"""
state_view = MockStateView({
to_address('validator_map'): b'this should be ignored',
to_address('my_id'): ValidatorInfo(
name='my_validator',
id='my_id',
signup_info=SignUpInfo(poet_public_key='my_public_key',
proof_data='beleive me',
anti_sybil_id='no sybil'),
transaction_id="signature"
).SerializeToString(),
to_address('another_id'): ValidatorInfo(
name='your_validator',
id='another_id',
signup_info=SignUpInfo(poet_public_key='your_public_key',
proof_data='you betcha',
anti_sybil_id='poor sybil'),
transaction_id="signature"
).SerializeToString()
})
validator_registry_view = ValidatorRegistryView(state_view)
infos = validator_registry_view.get_validators()
self.assertEqual(2, len(infos))
self.assertEqual('my_validator', infos['my_id'].name)
self.assertEqual('your_validator', infos['another_id'].name)
def test_get_validator_info(self):
"""Given a state view that contains a state entry for a given validator
info, verify that the validator registry returns a ValidatorInfo when
get_validator_info is called with the validator's id."""
state_view = MockStateView({
to_address('my_id'):
ValidatorInfo(registered='sure',
name='my_validator',
id='my_id',
signup_info=SignUpInfo(poet_public_key='my_pubkey',
proof_data='beleive me',
anti_sybil_id='no sybil'),
transaction_id="signature").SerializeToString()
})
validator_registry_view = ValidatorRegistryView(state_view)
info = validator_registry_view.get_validator_info('my_id')
self.assertEqual('my_id', info.id)
self.assertEqual('my_validator', info.name)
self.assertEqual('sure', info.registered)
self.assertEqual("signature", info.transaction_id)
self.assertEqual('my_pubkey', info.signup_info.poet_public_key)
self.assertEqual('beleive me', info.signup_info.proof_data)
self.assertEqual('no sybil', info.signup_info.anti_sybil_id)
def test_get_validators(self):
"""Given a state view with multiple validators, and the 'validator_map'
entry, verify that get_validators returns the list of just
ValidatorInfo instances.
"""
state_view = MockStateView({
to_address('validator_map'):
b'this should be ignored',
to_address('my_id'):
ValidatorInfo(name='my_validator',
id='my_id',
signup_info=SignUpInfo(poet_public_key='my_pubkey',
proof_data='beleive me',
anti_sybil_id='no sybil'),
transaction_id="signature").SerializeToString(),
to_address('another_id'):
ValidatorInfo(name='your_validator',
id='another_id',
signup_info=SignUpInfo(poet_public_key='your_pubkey',
proof_data='you betcha',
anti_sybil_id='poor sybil'),
transaction_id="signature").SerializeToString()
})
validator_registry_view = ValidatorRegistryView(state_view)
infos = validator_registry_view.get_validators()
self.assertEqual(2, len(infos))
self.assertEqual('my_validator', infos['my_id'].name)
self.assertEqual('your_validator', infos['another_id'].name)
def test_has_validator_info_not_exists(self):
"""Given a state view that does not contain a state view for a given
validator info, verify that has_validator_info returns False with an
unkown id.
"""
state_view = MockStateView({})
validator_registry_view = ValidatorRegistryView(state_view)
self.assertFalse(validator_registry_view.has_validator_info('my_id'))
def test_get_validator_info_not_exists(self):
"""Given a state view that does not contain a state view for a given
validator info, verify that it throws a key error on `get`.
"""
state_view = MockStateView({})
validator_registry_view = ValidatorRegistryView(state_view)
with self.assertRaises(KeyError):
validator_registry_view.get_validator_info('my_id')
def test_has_validator_info_not_exists(self):
"""Given a state view that does not contain a state view for a given
validator info, verify that has_validator_info returns False with an
unkown id.
"""
state_view = MockStateView({})
validator_registry_view = ValidatorRegistryView(state_view)
self.assertFalse(validator_registry_view.has_validator_info('my_id'))
def test_get_validator_info_not_exists(self):
"""Given a state view that does not contain a state view for a given
validator info, verify that it throws a key error on `get`.
"""
state_view = MockStateView({})
validator_registry_view = ValidatorRegistryView(state_view)
with self.assertRaises(KeyError):
validator_registry_view.get_validator_info('my_id')
def test_has_validator_info(self):
"""Given a state view that contains a state entry for a given validator
info, verify that the validator registry returns a true when
has_validator_info is called with the validator's id."""
state_view = MockStateView({
to_address('my_id'):
ValidatorInfo(name='my_validator',
id='my_id',
signup_info=SignUpInfo(poet_public_key='my_pubkey',
proof_data='beleive me',
anti_sybil_id='no sybil'),
transaction_id="signature").SerializeToString()
})
validator_registry_view = ValidatorRegistryView(state_view)
self.assertTrue(validator_registry_view.has_validator_info('my_id'))
def test_has_validator_info(self):
"""Given a state view that contains a state entry for a given validator
info, verify that the validator registry returns a true when
has_validator_info is called with the validator's id."""
state_view = MockStateView({
to_address('my_id'): ValidatorInfo(
name='my_validator',
id='my_id',
signup_info=SignUpInfo(poet_public_key='my_public_key',
proof_data='beleive me',
anti_sybil_id='no sybil'),
transaction_id="signature"
).SerializeToString()
})
validator_registry_view = ValidatorRegistryView(state_view)
self.assertTrue(validator_registry_view.has_validator_info('my_id'))
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
def compare_forks(self, cur_fork_head, new_fork_head):
"""Given the head of two forks, return which should be the fork that
the validator chooses. When this is called both forks consist of
only valid blocks.
Args:
cur_fork_head (Block): The current head of the block chain.
new_fork_head (Block): The head of the fork that is being
evaluated.
Returns:
Boolean: True if the new chain should replace the current chain.
False if the new chain should be discarded.
"""
chosen_fork_head = None
state_view = \
BlockWrapper.state_view_for_block(
block_wrapper=cur_fork_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)
current_fork_wait_certificate = \
utils.deserialize_wait_certificate(
block=cur_fork_head,
poet_enclave_module=poet_enclave_module)
new_fork_wait_certificate = \
utils.deserialize_wait_certificate(
block=new_fork_head,
poet_enclave_module=poet_enclave_module)
# If we ever get a new fork head that is not a PoET block, then bail
# out. This should never happen, but defensively protect against it.
if new_fork_wait_certificate is None:
raise \
TypeError(
'New fork head {} is not a PoET block'.format(
new_fork_head.identifier[:8]))
# Criterion #1: If the current fork head is not PoET, then check to see
# if the new fork head is building on top of it. That would be okay.
# However if not, then we don't have a good deterministic way of
# choosing a winner. Again, the latter should never happen, but
# defensively protect against it.
if current_fork_wait_certificate is None:
if new_fork_head.previous_block_id == cur_fork_head.identifier:
LOGGER.info(
'Choose new fork %s over current fork %s: '
'New fork head switches consensus to PoET',
new_fork_head.header_signature[:8],
cur_fork_head.header_signature[:8])
chosen_fork_head = new_fork_head
else:
raise \
TypeError(
'Trying to compare a PoET block {} to a non-PoET '
'block {} that is not the direct predecessor'.format(
new_fork_head.identifier[:8],
cur_fork_head.identifier[:8]))
# Criterion #2: If they share the same immediate previous block,
# then the one with the smaller wait duration is chosen
elif cur_fork_head.previous_block_id == \
new_fork_head.previous_block_id:
if current_fork_wait_certificate.duration < \
new_fork_wait_certificate.duration:
LOGGER.info(
'Choose current fork %s over new fork %s: '
'Current fork wait duration (%f) less than new fork wait '
'duration (%f)',
cur_fork_head.header_signature[:8],
new_fork_head.header_signature[:8],
current_fork_wait_certificate.duration,
new_fork_wait_certificate.duration)
chosen_fork_head = cur_fork_head
elif new_fork_wait_certificate.duration < \
current_fork_wait_certificate.duration:
LOGGER.info(
'Choose new fork %s over current fork %s: '
'New fork wait duration (%f) less than current fork wait '
'duration (%f)',
new_fork_head.header_signature[:8],
cur_fork_head.header_signature[:8],
new_fork_wait_certificate.duration,
current_fork_wait_certificate.duration)
chosen_fork_head = new_fork_head
# Criterion #3: If they don't share the same immediate previous
# block, then the one with the higher aggregate local mean wins
else:
# Get the consensus state for the current fork head and the
# block immediately before the new fork head (as we haven't
# committed to the block yet). So that the new fork doesn't
# have to fight with one hand tied behind its back, add the
# new fork head's wait certificate's local mean to the
# aggregate local mean for the predecessor block's consensus
# state for the comparison.
current_fork_consensus_state = \
ConsensusState.consensus_state_for_block_id(
block_id=cur_fork_head.identifier,
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)
new_fork_consensus_state = \
ConsensusState.consensus_state_for_block_id(
block_id=new_fork_head.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)
new_fork_aggregate_local_mean = \
new_fork_consensus_state.aggregate_local_mean + \
new_fork_wait_certificate.local_mean
if current_fork_consensus_state.aggregate_local_mean > \
new_fork_aggregate_local_mean:
LOGGER.info(
'Choose current fork %s over new fork %s: '
'Current fork aggregate local mean (%f) greater than new '
'fork aggregate local mean (%f)',
cur_fork_head.header_signature[:8],
new_fork_head.header_signature[:8],
current_fork_consensus_state.aggregate_local_mean,
new_fork_aggregate_local_mean)
chosen_fork_head = cur_fork_head
elif new_fork_aggregate_local_mean > \
current_fork_consensus_state.aggregate_local_mean:
LOGGER.info(
'Choose new fork %s over current fork %s: '
'New fork aggregate local mean (%f) greater than current '
'fork aggregate local mean (%f)',
new_fork_head.header_signature[:8],
cur_fork_head.header_signature[:8],
new_fork_aggregate_local_mean,
current_fork_consensus_state.aggregate_local_mean)
chosen_fork_head = new_fork_head
# Criterion #4: If we have gotten to this point and we have not chosen
# yet, we are going to fall back on using the block identifiers
# (header signatures) . The lexicographically larger one will be the
# chosen one. The chance that they are equal are infinitesimally
# small.
if chosen_fork_head is None:
if cur_fork_head.header_signature > \
new_fork_head.header_signature:
LOGGER.info(
'Choose current fork %s over new fork %s: '
'Current fork header signature (%s) greater than new fork '
'header signature (%s)',
cur_fork_head.header_signature[:8],
new_fork_head.header_signature[:8],
cur_fork_head.header_signature[:8],
new_fork_head.header_signature[:8])
chosen_fork_head = cur_fork_head
else:
LOGGER.info(
'Choose new fork %s over current fork %s: '
'New fork header signature (%s) greater than current fork '
'header signature (%s)',
new_fork_head.header_signature[:8],
cur_fork_head.header_signature[:8],
new_fork_head.header_signature[:8],
cur_fork_head.header_signature[:8])
chosen_fork_head = new_fork_head
# Now that we have chosen a fork for the chain head, if we chose the
# new fork and it is a PoET block (i.e., it has a wait certificate),
# we need to create consensus state store information for the new
# fork's chain head.
if chosen_fork_head == new_fork_head:
# Get the state view for the previous block in the chain so we can
# create a PoET enclave
previous_block = None
try:
previous_block = \
self._block_cache[new_fork_head.previous_block_id]
except KeyError:
pass
state_view = \
BlockWrapper.state_view_for_block(
block_wrapper=previous_block,
state_view_factory=self._state_view_factory)
validator_registry_view = ValidatorRegistryView(state_view)
try:
# Get the validator info for the validator that claimed the
# fork head
validator_info = \
validator_registry_view.get_validator_info(
new_fork_head.header.signer_public_key)
# Get the consensus state for the new fork head's previous
# block, let the consensus state update itself appropriately
# based upon the validator claiming a block, and then
# associate the consensus state with the new block in the
# store.
consensus_state = \
ConsensusState.consensus_state_for_block_id(
block_id=new_fork_head.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)
consensus_state.validator_did_claim_block(
validator_info=validator_info,
wait_certificate=new_fork_wait_certificate,
poet_settings_view=PoetSettingsView(state_view))
self._consensus_state_store[new_fork_head.identifier] = \
consensus_state
LOGGER.debug(
'Create consensus state: BID=%s, ALM=%f, TBCC=%d',
new_fork_head.identifier[:8],
consensus_state.aggregate_local_mean,
consensus_state.total_block_claim_count)
except KeyError:
# This _should_ never happen. The new potential fork head
# has to have been a PoET block and for it to be verified
# by the PoET block verifier, it must have been signed by
# validator in the validator registry. If not found, we
# are going to just stick with the current fork head.
LOGGER.error(
'New fork head claimed by validator not in validator '
'registry: %s...%s',
new_fork_head.header.signer_public_key[:8],
new_fork_head.header.signer_public_key[-8:])
chosen_fork_head = cur_fork_head
return chosen_fork_head == new_fork_head
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 (signing public key: %s) is claiming blocks '
'too frequently.',
block_header.previous_block_id[:8],
block_header.signer_public_key)
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)
validator_registry_view = ValidatorRegistryView(state_view)
try:
# 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_pubkey)
except KeyError:
raise \
ValueError(
'Received block from an unregistered validator '
'{}...{}'.format(
block_wrapper.header.signer_pubkey[:8],
block_wrapper.header.signer_pubkey[-8:]))
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:])
# Create a list of certificates leading up to this block.
# This seems to have a little too much knowledge of the
# WaitTimer implementation, but there is no use getting more
# than WaitTimer.certificate_sample_length wait certificates.
certificates = \
utils.build_certificate_list(
block_header=block_wrapper.header,
block_cache=self._block_cache,
poet_enclave_module=poet_enclave_module,
maximum_number=WaitTimer.certificate_sample_length)
# 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:
raise \
ValueError(
'Being asked to verify a block that was not '
'created by PoET consensus module')
poet_public_key = \
validator_info.signup_info.poet_public_key
wait_certificate.check_valid(
poet_enclave_module=poet_enclave_module,
certificates=certificates,
poet_public_key=poet_public_key)
# Get the consensus state for the block that is being built
# upon, fetch the validator state for this validator, and then
# see if that validator has already claimed the key bock limit
# for its current PoET key pair. If so, then we reject the
# block.
consensus_state = \
utils.get_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)
validator_state = \
utils.get_current_validator_state(
validator_info=validator_info,
consensus_state=consensus_state,
block_cache=self._block_cache)
poet_config_view = PoetConfigView(state_view=state_view)
if validator_state.poet_public_key == poet_public_key and \
validator_state.key_block_claim_count >= \
poet_config_view.key_block_claim_limit:
raise \
ValueError(
'Validator {} has already reached claim block limit '
'for current PoET key pair: {} >= {}'.format(
validator_info.name,
validator_state.key_block_claim_count,
poet_config_view.key_block_claim_limit))
# While having a block claim delay is nice, it turns out that in
# practice the claim delay should not be more than one less than
# the number of validators. It helps to imagine the scenario
# where each validator hits their block claim limit in sequential
# blocks and their new validator registry information is updated
# in the following block by another validator, assuming that there
# were no forks. If there are N validators, once all N validators
# have updated their validator registry information, there will
# have been N-1 block commits and the Nth validator will only be
# able to get its updated validator registry information updated
# if the first validator that kicked this off is now able to claim
# a block. If the block claim delay was greater than or equal to
# the number of validators, at this point no validators would be
# able to claim a block.
number_of_validators = \
len(validator_registry_view.get_validators())
block_claim_delay = \
min(
poet_config_view.block_claim_delay,
number_of_validators - 1)
# While a validator network is starting up, we need to be careful
# about applying the block claim delay because if we are too
# aggressive we will get ourselves into a situation where the
# block claim delay will prevent any validators from claiming
# blocks. So, until we get at least block_claim_delay blocks
# we are going to choose not to enforce the delay.
if consensus_state.total_block_claim_count <= block_claim_delay:
LOGGER.debug(
'Skipping block claim delay check. Only %d block(s) in '
'the chain. Claim delay is %d block(s). %d validator(s) '
'registered.', consensus_state.total_block_claim_count,
block_claim_delay, number_of_validators)
return True
blocks_since_registration = \
block_wrapper.block_num - \
validator_state.commit_block_number - 1
if block_claim_delay > blocks_since_registration:
raise \
ValueError(
'Validator {} claiming too early. Block: {}, '
'registered in: {}, wait until after: {}.'.format(
validator_info.name,
block_wrapper.block_num,
validator_state.commit_block_number,
validator_state.commit_block_number +
block_claim_delay))
LOGGER.debug(
'%d block(s) claimed since %s was registered and block '
'claim delay is %d block(s). Check passed.',
blocks_since_registration, validator_info.name,
block_claim_delay)
except ValueError as error:
LOGGER.error('Failed to verify block: %s', error)
return False
return True
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)
# 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_pubkey
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 our cached
# PoET public 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.
if validator_info is None:
if PoetBlockPublisher._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)
return False
# Otherwise, we have a current validator registry entry. In that
# case, we need to make sure that we are using the same PPK that the
# other validators think we are using. If not, then we need to switch
# the PoET enclave to using the correct keys.
elif validator_info.signup_info.poet_public_key != \
PoetBlockPublisher._poet_public_key:
# Retrieve the key state corresponding to the PoET public key and
# use it to re-establish the key used by the enclave.
poet_key_state = \
self._poet_key_state_store[
validator_info.signup_info.poet_public_key]
PoetBlockPublisher._poet_public_key = \
SignupInfo.unseal_signup_data(
poet_enclave_module=poet_enclave_module,
validator_address=block_header.signer_pubkey,
sealed_signup_data=poet_key_state.sealed_signup_data)
assert PoetBlockPublisher._poet_public_key == \
validator_info.signup_info.poet_public_key
LOGGER.debug('Switched to public key: %s...%s',
PoetBlockPublisher._poet_public_key[:8],
PoetBlockPublisher._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 = \
utils.get_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)
validator_state = \
utils.get_current_validator_state(
validator_info=validator_info,
consensus_state=consensus_state,
block_cache=self._block_cache)
poet_config_view = PoetConfigView(state_view)
# 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.
key_block_claim_limit = poet_config_view.key_block_claim_limit
if utils.validator_has_claimed_maximum_number_of_blocks(
validator_info=validator_info,
validator_state=validator_state,
key_block_claim_limit=key_block_claim_limit):
# 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[
PoetBlockPublisher._poet_public_key]
if not poet_key_state.has_been_refreshed:
LOGGER.info('Reached block claim limit (%d) for key: %s...%s',
key_block_claim_limit,
PoetBlockPublisher._poet_public_key[:8],
PoetBlockPublisher._poet_public_key[-8:])
sealed_signup_data = poet_key_state.sealed_signup_data
self._poet_key_state_store[
PoetBlockPublisher._poet_public_key] = \
PoetKeyState(
sealed_signup_data=sealed_signup_data,
has_been_refreshed=True)
self._register_signup_information(
block_header=block_header,
poet_enclave_module=poet_enclave_module)
LOGGER.error(
'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 utils.validator_has_claimed_too_early(
validator_info=validator_info,
consensus_state=consensus_state,
block_number=block_header.block_num,
validator_registry_view=validator_registry_view,
poet_config_view=poet_config_view,
block_store=self._block_cache.block_store):
LOGGER.error(
'Reject building on block %s: Validator has not waited long '
'enough since registering validator information.',
block_header.previous_block_id[:8])
return False
# Create a list of certificates for the wait timer. This seems to
# have a little too much knowledge of the WaitTimer implementation,
# but there is no use getting more than
# WaitTimer.certificate_sample_length wait certificates.
certificates = \
utils.build_certificate_list(
block_header=block_header,
block_cache=self._block_cache,
poet_enclave_module=poet_enclave_module,
maximum_number=WaitTimer.certificate_sample_length)
# 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
wait_timer = \
WaitTimer.create_wait_timer(
poet_enclave_module=poet_enclave_module,
validator_address=block_header.signer_pubkey,
certificates=list(certificates))
# 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 utils.validator_has_claimed_too_frequently(
validator_info=validator_info,
previous_block_id=block_header.previous_block_id,
consensus_state=consensus_state,
poet_config_view=poet_config_view,
population_estimate=wait_timer.population_estimate,
block_cache=self._block_cache,
poet_enclave_module=poet_enclave_module):
LOGGER.error(
'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 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_pubkey
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)
return False
# Otherwise, we have a current validator registry entry. In that
# case, we need to make sure that we are using the same PPK that the
# other validators think we are using. If not, then we need to switch
# the PoET enclave to using the correct keys.
elif validator_info.signup_info.poet_public_key != \
active_poet_public_key:
# Retrieve the key state corresponding to the PoET public key and
# use it to re-establish the key used by the enclave. Also update
# the active PoET public key.
poet_key_state = \
self._poet_key_state_store[
validator_info.signup_info.poet_public_key]
active_poet_public_key = \
SignupInfo.unseal_signup_data(
poet_enclave_module=poet_enclave_module,
sealed_signup_data=poet_key_state.sealed_signup_data)
self._poet_key_state_store.active_key = active_poet_public_key
assert active_poet_public_key == \
validator_info.signup_info.poet_public_key
LOGGER.debug(
'Switched to 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
self._poet_key_state_store[active_poet_public_key] = \
PoetKeyState(
sealed_signup_data=sealed_signup_data,
has_been_refreshed=True)
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
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,
validator_address=block_header.signer_pubkey,
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 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.
"""
# 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)
# Check the consensus state to see if we have current sealed signup
# information.
consensus_state = \
utils.get_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)
if consensus_state is not None and \
consensus_state.sealed_signup_data is not None:
# Check to see if the sealed signup data we have cached is the
# same as what is in the consensus store. If not, then it is
# stale and so we need to unseal it and update our cached copy.
if consensus_state.sealed_signup_data != \
PoetBlockPublisher._sealed_signup_data:
LOGGER.debug('Unseal signup data %s...%s',
consensus_state.sealed_signup_data[:8],
consensus_state.sealed_signup_data[-8:])
PoetBlockPublisher._sealed_signup_data = \
consensus_state.sealed_signup_data
PoetBlockPublisher._poet_public_key = \
SignupInfo.unseal_signup_data(
poet_enclave_module=poet_enclave_module,
validator_address=block_header.signer_pubkey,
sealed_signup_data=consensus_state.sealed_signup_data)
# Otherwise, if we don't already have a public key, we need to create
# signup information and create a transaction to add it to the
# validator registry.
elif PoetBlockPublisher._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)
return False
# Otherwise, at this point we need to check the validator registry to
# see if our _current_ validator registry information was added to the
# validator registry.
else:
validator_registry_view = ValidatorRegistryView(state_view)
try:
validator_id = block_header.signer_pubkey
validator_info = \
validator_registry_view.get_validator_info(
validator_id=validator_id)
LOGGER.debug(
'Our Validator Registry Entry: 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:])
# We need to verify that our validator registry entry is
# current - basically this means verifying that the PoET
# public key that will be used to verify the validity of
# our wait certificates is the PoET public key matching our
# current private key.
if validator_info.signup_info.poet_public_key != \
PoetBlockPublisher._poet_public_key:
LOGGER.debug(
'Our Validator Registry Entry PoET public key '
'(%s...%s) doesn'
't match the PoET public key '
'expected (%s...%s)',
validator_info.signup_info.poet_public_key[:8],
validator_info.signup_info.poet_public_key[-8:],
PoetBlockPublisher._poet_public_key[:8],
PoetBlockPublisher._poet_public_key[-8:])
return False
# At this point, we know that we are in the validator registry
# and the entry is current. We can save the sealed signup
# data to the consensus state for the previous block and can
# clear out our cached copies of the sealed signup data and
# the PoET public key.
if consensus_state is None:
consensus_state = ConsensusState()
consensus_state.sealed_signup_data = \
PoetBlockPublisher._sealed_signup_data
self._consensus_state_store[block_header.previous_block_id] = \
consensus_state
PoetBlockPublisher._sealed_signup_data = None
PoetBlockPublisher._poet_public_key = None
except KeyError:
LOGGER.debug(
'We cannot initialize the block because our PoET signup '
'information is not in the validator registry')
return False
# Since we are registering, don't bother trying to initialize
# the block
return False
# Create a list of certificates for the wait timer. This seems to have
# a little too much knowledge of the WaitTimer implementation, but
# there is no use getting more than
# WaitTimer.certificate_sample_length wait certificates.
certificates = \
utils.build_certificate_list(
block_header=block_header,
block_cache=self._block_cache,
poet_enclave_module=poet_enclave_module,
maximum_number=WaitTimer.certificate_sample_length)
# 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
self._wait_timer = \
WaitTimer.create_wait_timer(
poet_enclave_module=poet_enclave_module,
validator_address=block_header.signer_pubkey,
certificates=list(certificates))
LOGGER.debug('Created wait timer: %s', self._wait_timer)
return True
def compare_forks(self, cur_fork_head, new_fork_head):
"""Given the head of two forks, return which should be the fork that
the validator chooses. When this is called both forks consist of
only valid blocks.
Args:
cur_fork_head (Block): The current head of the block chain.
new_fork_head (Block): The head of the fork that is being
evaluated.
Returns:
Boolean: True if the new chain should replace the current chain.
False if the new chain should be discarded.
"""
chosen_fork_head = None
if new_fork_head.block_num > cur_fork_head.block_num:
LOGGER.info(
'Chain with new fork head %s...%s longer (%d) than current '
'chain head %s...%s (%d)', new_fork_head.header_signature[:8],
new_fork_head.header_signature[-8:], new_fork_head.block_num,
cur_fork_head.header_signature[:8],
cur_fork_head.header_signature[-8:], cur_fork_head.block_num)
chosen_fork_head = new_fork_head
elif new_fork_head.block_num < cur_fork_head.block_num:
LOGGER.info(
'Chain with current head %s...%s longer (%d) than new fork '
'head %s...%s (%d)', cur_fork_head.header_signature[:8],
cur_fork_head.header_signature[-8:], cur_fork_head.block_num,
new_fork_head.header_signature[:8],
new_fork_head.header_signature[-8:], new_fork_head.block_num)
chosen_fork_head = cur_fork_head
elif new_fork_head.header_signature > cur_fork_head.header_signature:
LOGGER.info(
'Signature of new fork head (%s...%s) > than current '
'(%s...%s)', new_fork_head.header_signature[:8],
new_fork_head.header_signature[-8:],
cur_fork_head.header_signature[:8],
cur_fork_head.header_signature[-8:])
chosen_fork_head = new_fork_head
else:
LOGGER.info(
'Signature of current fork head (%s...%s) >= than new '
'(%s...%s)', cur_fork_head.header_signature[:8],
cur_fork_head.header_signature[-8:],
new_fork_head.header_signature[:8],
new_fork_head.header_signature[-8:])
chosen_fork_head = cur_fork_head
# Now that we have chosen a fork for the chain head, if
# we chose the new fork, we need to create consensus state
# store information for the new fork's chain head.
if chosen_fork_head == new_fork_head:
# Get the state view for the previous block in the chain so we can
# create a PoET enclave
previous_block = None
try:
previous_block = \
self._block_cache[new_fork_head.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)
validator_registry_view = ValidatorRegistryView(state_view)
try:
# Get the validator info for the validator that claimed the
# fork head
validator_info = \
validator_registry_view.get_validator_info(
new_fork_head.header.signer_pubkey)
# Get the consensus state for the new fork head's previous
# block and update the consensus-wide statistics for the new
# fork head.
consensus_state = \
utils.get_consensus_state_for_block_id(
block_id=new_fork_head.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)
consensus_state.total_block_claim_count += 1
# Get and update the validator state/statistics for the
# validator that claimed the new fork head.
validator_state = \
utils.get_current_validator_state(
validator_info=validator_info,
consensus_state=consensus_state,
block_cache=self._block_cache)
consensus_state.set_validator_state(
validator_id=validator_info.id,
validator_state=utils.create_next_validator_state(
validator_info=validator_info,
current_validator_state=validator_state))
# Store the updated consensus state for this block.
self._consensus_state_store[new_fork_head.identifier] = \
consensus_state
LOGGER.debug('Create consensus state: BID=%s, TBCC=%d',
new_fork_head.identifier[:8],
consensus_state.total_block_claim_count)
except KeyError:
# This _should_ never happen. The new potential fork head
# has to have been a PoET block and for it to be verified
# by the PoET block verifier, it must have been signed by
# validator in the validator registry. If not found, we
# are going to just stick with the current fork head.
LOGGER.error(
'New fork head claimed by validator not in validator '
'registry: %s...%s',
new_fork_head.header.signer_pubkey[:8],
new_fork_head.header.signer_pubkey[-8:])
chosen_fork_head = cur_fork_head
return chosen_fork_head == new_fork_head
def compare_forks(self, cur_fork_head, new_fork_head):
"""Given the head of two forks, return which should be the fork that
the validator chooses. When this is called both forks consist of
only valid blocks.
Args:
cur_fork_head (Block): The current head of the block chain.
new_fork_head (Block): The head of the fork that is being
evaluated.
Returns:
Boolean: True if the new chain should replace the current chain.
False if the new chain should be discarded.
"""
chosen_fork_head = None
state_view = \
BlockWrapper.state_view_for_block(
block_wrapper=cur_fork_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)
current_fork_wait_certificate = \
utils.deserialize_wait_certificate(
block=cur_fork_head,
poet_enclave_module=poet_enclave_module)
new_fork_wait_certificate = \
utils.deserialize_wait_certificate(
block=new_fork_head,
poet_enclave_module=poet_enclave_module)
# If we ever get a new fork head that is not a PoET block, then bail
# out. This should never happen, but defensively protect against it.
if new_fork_wait_certificate is None:
raise \
TypeError(
'New fork head {} is not a PoET block'.format(
new_fork_head.identifier[:8]))
# Criterion #1: If the current fork head is not PoET, then check to see
# if the new fork head is building on top of it. That would be okay.
# However if not, then we don't have a good deterministic way of
# choosing a winner. Again, the latter should never happen, but
# defensively protect against it.
if current_fork_wait_certificate is None:
if new_fork_head.previous_block_id == cur_fork_head.identifier:
LOGGER.info(
'Choose new fork %s over current fork %s: '
'New fork head switches consensus to PoET',
new_fork_head.header_signature[:8],
cur_fork_head.header_signature[:8])
chosen_fork_head = new_fork_head
else:
raise \
TypeError(
'Trying to compare a PoET block {} to a non-PoET '
'block {} that is not the direct predecessor'.format(
new_fork_head.identifier[:8],
cur_fork_head.identifier[:8]))
# Criterion #2: If they share the same immediate previous block,
# then the one with the smaller wait duration is chosen
elif cur_fork_head.previous_block_id == \
new_fork_head.previous_block_id:
if current_fork_wait_certificate.duration < \
new_fork_wait_certificate.duration:
LOGGER.info(
'Choose current fork %s over new fork %s: '
'Current fork wait duration (%f) less than new fork wait '
'duration (%f)', cur_fork_head.header_signature[:8],
new_fork_head.header_signature[:8],
current_fork_wait_certificate.duration,
new_fork_wait_certificate.duration)
chosen_fork_head = cur_fork_head
elif new_fork_wait_certificate.duration < \
current_fork_wait_certificate.duration:
LOGGER.info(
'Choose new fork %s over current fork %s: '
'New fork wait duration (%f) less than current fork wait '
'duration (%f)', new_fork_head.header_signature[:8],
cur_fork_head.header_signature[:8],
new_fork_wait_certificate.duration,
current_fork_wait_certificate.duration)
chosen_fork_head = new_fork_head
# Criterion #3: If they don't share the same immediate previous
# block, then the one with the higher aggregate local mean wins
else:
# Get the consensus state for the current fork head and the
# block immediately before the new fork head (as we haven't
# committed to the block yet). So that the new fork doesn't
# have to fight with one hand tied behind its back, add the
# new fork head's wait certificate's local mean to the
# aggregate local mean for the predecessor block's consensus
# state for the comparison.
current_fork_consensus_state = \
ConsensusState.consensus_state_for_block_id(
block_id=cur_fork_head.identifier,
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)
new_fork_consensus_state = \
ConsensusState.consensus_state_for_block_id(
block_id=new_fork_head.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)
new_fork_aggregate_local_mean = \
new_fork_consensus_state.aggregate_local_mean + \
new_fork_wait_certificate.local_mean
if current_fork_consensus_state.aggregate_local_mean > \
new_fork_aggregate_local_mean:
LOGGER.info(
'Choose current fork %s over new fork %s: '
'Current fork aggregate local mean (%f) greater than new '
'fork aggregate local mean (%f)',
cur_fork_head.header_signature[:8],
new_fork_head.header_signature[:8],
current_fork_consensus_state.aggregate_local_mean,
new_fork_aggregate_local_mean)
chosen_fork_head = cur_fork_head
elif new_fork_aggregate_local_mean > \
current_fork_consensus_state.aggregate_local_mean:
LOGGER.info(
'Choose new fork %s over current fork %s: '
'New fork aggregate local mean (%f) greater than current '
'fork aggregate local mean (%f)',
new_fork_head.header_signature[:8],
cur_fork_head.header_signature[:8],
new_fork_aggregate_local_mean,
current_fork_consensus_state.aggregate_local_mean)
chosen_fork_head = new_fork_head
# Criterion #4: If we have gotten to this point and we have not chosen
# yet, we are going to fall back on using the block identifiers
# (header signatures) . The lexicographically larger one will be the
# chosen one. The chance that they are equal are infinitesimally
# small.
if chosen_fork_head is None:
if cur_fork_head.header_signature > \
new_fork_head.header_signature:
LOGGER.info(
'Choose current fork %s over new fork %s: '
'Current fork header signature (%s) greater than new fork '
'header signature (%s)',
cur_fork_head.header_signature[:8],
new_fork_head.header_signature[:8],
cur_fork_head.header_signature[:8],
new_fork_head.header_signature[:8])
chosen_fork_head = cur_fork_head
else:
LOGGER.info(
'Choose new fork %s over current fork %s: '
'New fork header signature (%s) greater than current fork '
'header signature (%s)',
new_fork_head.header_signature[:8],
cur_fork_head.header_signature[:8],
new_fork_head.header_signature[:8],
cur_fork_head.header_signature[:8])
chosen_fork_head = new_fork_head
# Now that we have chosen a fork for the chain head, if we chose the
# new fork and it is a PoET block (i.e., it has a wait certificate),
# we need to create consensus state store information for the new
# fork's chain head.
if chosen_fork_head == new_fork_head:
# Get the state view for the previous block in the chain so we can
# create a PoET enclave
previous_block = None
try:
previous_block = \
self._block_cache[new_fork_head.previous_block_id]
except KeyError:
pass
state_view = \
BlockWrapper.state_view_for_block(
block_wrapper=previous_block,
state_view_factory=self._state_view_factory)
validator_registry_view = ValidatorRegistryView(state_view)
try:
# Get the validator info for the validator that claimed the
# fork head
validator_info = \
validator_registry_view.get_validator_info(
new_fork_head.header.signer_public_key)
# Get the consensus state for the new fork head's previous
# block, let the consensus state update itself appropriately
# based upon the validator claiming a block, and then
# associate the consensus state with the new block in the
# store.
consensus_state = \
ConsensusState.consensus_state_for_block_id(
block_id=new_fork_head.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)
consensus_state.validator_did_claim_block(
validator_info=validator_info,
wait_certificate=new_fork_wait_certificate,
poet_settings_view=PoetSettingsView(state_view))
self._consensus_state_store[new_fork_head.identifier] = \
consensus_state
LOGGER.debug('Create consensus state: BID=%s, ALM=%f, TBCC=%d',
new_fork_head.identifier[:8],
consensus_state.aggregate_local_mean,
consensus_state.total_block_claim_count)
except KeyError:
# This _should_ never happen. The new potential fork head
# has to have been a PoET block and for it to be verified
# by the PoET block verifier, it must have been signed by
# validator in the validator registry. If not found, we
# are going to just stick with the current fork head.
LOGGER.error(
'New fork head claimed by validator not in validator '
'registry: %s...%s',
new_fork_head.header.signer_public_key[:8],
new_fork_head.header.signer_public_key[-8:])
chosen_fork_head = cur_fork_head
return chosen_fork_head == new_fork_head
def get_consensus_state_for_block_id(block_id, block_cache, state_view_factory,
consensus_state_store,
poet_enclave_module):
"""Returns the consensus state for the block referenced by block ID,
creating it from the consensus state history if necessary.
Args:
block_id (str): The ID of the block for which consensus state will
be returned.
block_cache (BlockCache): The block store cache
state_view_factory (StateViewFactory): A factory that can be used
to create state view object corresponding to blocks
consensus_state_store (ConsensusStateStore): The consensus state
store
poet_enclave_module (module): The PoET enclave module
Returns:
ConsensusState object representing the consensus state for the block
referenced by block_id
"""
# Starting at the chain head, walk the block store backwards until we
# either get to the root or we get a block for which we have already
# created consensus state
block = \
block_cache[block_id] if block_id != NULL_BLOCK_IDENTIFIER else None
consensus_state = None
block_ids = collections.deque()
while block is not None:
# Try to fetch the consensus state. If that succeeds, we can
# stop walking back as we can now build on that consensus
# state.
consensus_state = consensus_state_store.get(block.identifier)
if consensus_state is not None:
break
# If this is a PoET block, then we want to create consensus state
# for it when we are done
if deserialize_wait_certificate(block, poet_enclave_module):
LOGGER.debug(
'We need to build consensus state for block ID %s...%s',
block.identifier[:8], block.identifier[-8:])
block_ids.appendleft(block.identifier)
# Move to the previous block
block = \
block_cache[block.previous_block_id] \
if block.previous_block_id != NULL_BLOCK_IDENTIFIER else None
# If didn't find any consensus state, see if there is any "before" any
# blocks were created (this might be because we are the first validator
# and PoET signup information was created, including sealed signup data
# that was saved in the consensus state store).
if consensus_state is None:
consensus_state = consensus_state_store.get(NULL_BLOCK_IDENTIFIER)
# At this point, if we have not found any consensus state, we need to
# create default state from which we can build upon
if consensus_state is None:
consensus_state = ConsensusState()
# Now, walking forward through the blocks for which we were supposed to
# create consensus state, we are going to create and store state for each
# one so that the next time we don't have to walk so far back through the
# block chain.
for identifier in block_ids:
block = block_cache[identifier]
# Get the validator registry view for this block's state view and
# then fetch the validator info for the validator that signed this
# block.
state_view = state_view_factory.create_view(block.state_root_hash)
validator_registry_view = ValidatorRegistryView(state_view)
validator_id = block.header.signer_pubkey
validator_info = \
validator_registry_view.get_validator_info(
validator_id=validator_id)
# Fetch the current validator state, set/update the validator state
# in the consensus state object, and then create the consensus state
# in the consensus state store and associate it with this block
validator_state = \
consensus_state.get_validator_state(validator_id=validator_id)
consensus_state.set_validator_state(
validator_id=validator_id,
validator_state=create_validator_state(
validator_info=validator_info,
current_validator_state=validator_state))
LOGGER.debug('Store consensus state for block ID %s...%s',
identifier[:8], identifier[-8:])
consensus_state_store[identifier] = consensus_state
return consensus_state
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)
validator_registry_view = ValidatorRegistryView(state_view)
try:
# 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_pubkey)
except KeyError:
raise \
ValueError(
'Received block from an unregistered validator '
'{}...{}'.format(
block_wrapper.header.signer_pubkey[:8],
block_wrapper.header.signer_pubkey[-8:]))
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:])
# Create a list of certificates leading up to this block.
# This seems to have a little too much knowledge of the
# WaitTimer implementation, but there is no use getting more
# than WaitTimer.certificate_sample_length wait certificates.
certificates = \
utils.build_certificate_list(
block_header=block_wrapper.header,
block_cache=self._block_cache,
poet_enclave_module=poet_enclave_module,
maximum_number=WaitTimer.certificate_sample_length)
# 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:
raise \
ValueError(
'Being asked to verify a block that was not '
'created by PoET consensus module')
poet_public_key = \
validator_info.signup_info.poet_public_key
wait_certificate.check_valid(
poet_enclave_module=poet_enclave_module,
certificates=certificates,
poet_public_key=poet_public_key)
except ValueError as error:
LOGGER.error('Failed to verify block: %s', error)
return False
return True
def consensus_state_for_block_id(block_id,
block_cache,
state_view_factory,
consensus_state_store,
poet_enclave_module):
"""Returns the consensus state for the block referenced by block ID,
creating it from the consensus state history if necessary.
Args:
block_id (str): The ID of the block for which consensus state will
be returned.
block_cache (BlockCache): The block store cache
state_view_factory (StateViewFactory): A factory that can be used
to create state view object corresponding to blocks
consensus_state_store (ConsensusStateStore): The consensus state
store that is used to store interim consensus state created
up to resulting consensus state
poet_enclave_module (module): The PoET enclave module
Returns:
ConsensusState object representing the consensus state for the
block referenced by block_id
"""
consensus_state = None
previous_wait_certificate = None
blocks = collections.OrderedDict()
# Starting at the chain head, walk the block store backwards until we
# either get to the root or we get a block for which we have already
# created consensus state
current_id = block_id
while True:
block = \
ConsensusState._block_for_id(
block_id=current_id,
block_cache=block_cache)
if block is None:
break
# Try to fetch the consensus state. If that succeeds, we can
# stop walking back as we can now build on that consensus
# state.
consensus_state = consensus_state_store.get(block_id=current_id)
if consensus_state is not None:
break
wait_certificate = \
utils.deserialize_wait_certificate(
block=block,
poet_enclave_module=poet_enclave_module)
# If this is a PoET block (i.e., it has a wait certificate), get
# the validator info for the validator that signed this block and
# add the block information we will need to set validator state in
# the block's consensus state.
if wait_certificate is not None:
state_view = \
state_view_factory.create_view(
state_root_hash=block.state_root_hash)
validator_registry_view = \
ValidatorRegistryView(state_view=state_view)
validator_info = \
validator_registry_view.get_validator_info(
validator_id=block.header.signer_public_key)
LOGGER.debug(
'We need to build consensus state for block: %s...%s',
current_id[:8],
current_id[-8:])
blocks[current_id] = \
ConsensusState._BlockInfo(
wait_certificate=wait_certificate,
validator_info=validator_info,
poet_settings_view=PoetSettingsView(state_view))
# Otherwise, this is a non-PoET block. If we don't have any blocks
# yet or the last block we processed was a PoET block, put a
# placeholder in the list so that when we get to it we know that we
# need to reset the statistics.
elif not blocks or previous_wait_certificate is not None:
blocks[current_id] = \
ConsensusState._BlockInfo(
wait_certificate=None,
validator_info=None,
poet_settings_view=None)
previous_wait_certificate = wait_certificate
# Move to the previous block
current_id = block.previous_block_id
# At this point, if we have not found any consensus state, we need to
# create default state from which we can build upon
if consensus_state is None:
consensus_state = ConsensusState()
# Now, walk through the blocks for which we were supposed to create
# consensus state, from oldest to newest (i.e., in the reverse order in
# which they were added), and store state for PoET blocks so that the
# next time we don't have to walk so far back through the block chain.
for current_id, block_info in reversed(blocks.items()):
# If the block was not a PoET block (i.e., didn't have a wait
# certificate), reset the consensus state statistics. We are not
# going to store this in the consensus state store, but we will use
# it as the starting for the next PoET block.
if block_info.wait_certificate is None:
consensus_state = ConsensusState()
# Otherwise, let the consensus state update itself appropriately
# based upon the validator claiming a block, and then associate the
# consensus state with the new block in the store.
# validator state for the validator which claimed the block, create
# updated validator state for the validator, set/update the
# validator state in the consensus state object, and then associate
# the consensus state with the corresponding block in the consensus
# state store.
else:
consensus_state.validator_did_claim_block(
validator_info=block_info.validator_info,
wait_certificate=block_info.wait_certificate,
poet_settings_view=block_info.poet_settings_view)
consensus_state_store[current_id] = consensus_state
LOGGER.debug(
'Create consensus state: BID=%s, ALM=%f, TBCC=%d',
current_id[:8],
consensus_state.aggregate_local_mean,
consensus_state.total_block_claim_count)
return consensus_state
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.
"""
# HACER: If we don't have any validators registered yet, we are going
# to immediately approve the block. We cannot test the block's wait
# certificate until we can retrieve the block signer's corresponding
# public key. We cannot do that until the genesis block is populated
# with the "initial" validator's signup information
validator_registry_view = ValidatorRegistryView(self._state_view)
if len(validator_registry_view.get_validators()) > 0:
try:
# Grab the validator info based upon the block signer's public
# key
validator_info = \
validator_registry_view.get_validator_info(
block_wrapper.header.signer_pubkey)
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:])
# Create a list of certificates leading up to this block.
# This seems to have a little too much knowledge of the
# WaitTimer implementation, but there is no use getting more
# than WaitTimer.certificate_sample_length wait certificates.
certificates = \
utils.build_certificate_list(
block_header=block_wrapper.header,
block_cache=self._block_cache,
poet_enclave_module=self._poet_enclave_module,
maximum_number=WaitTimer.certificate_sample_length)
# 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=self._poet_enclave_module)
wait_certificate.check_valid(
poet_enclave_module=self._poet_enclave_module,
certificates=certificates,
poet_public_key=validator_info.signup_info.poet_public_key)
except KeyError:
LOGGER.error(
'Attempted to verify block from validator with no '
'validator registry entry')
return False
except ValueError as ve:
LOGGER.error('Wait certificate is not valid: %s', str(ve))
LOGGER.warning('We will accept for now')
else:
LOGGER.warning(
'Block accepted by default because no validators registered')
return True
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.
"""
# 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)
# 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_pubkey
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 our cached
# PoET public 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.
if validator_info is None:
if PoetBlockPublisher._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)
return False
# Otherwise, we have a current validator registry entry. In that
# case, we need to make sure that we are using the same PPK that the
# other validators think we are using. If not, then we need to switch
# the PoET enclave to using the correct keys.
elif validator_info.signup_info.poet_public_key != \
PoetBlockPublisher._poet_public_key:
# Retrieve the key state corresponding to the PoET public key and
# use it to re-establish the key used by the enclave.
poet_key_state = \
self._poet_key_state_store[
validator_info.signup_info.poet_public_key]
PoetBlockPublisher._poet_public_key = \
SignupInfo.unseal_signup_data(
poet_enclave_module=poet_enclave_module,
validator_address=block_header.signer_pubkey,
sealed_signup_data=poet_key_state.sealed_signup_data)
assert PoetBlockPublisher._poet_public_key == \
validator_info.signup_info.poet_public_key
LOGGER.debug('Switched to public key: %s...%s',
PoetBlockPublisher._poet_public_key[:8],
PoetBlockPublisher._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 = \
utils.get_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)
validator_state = \
utils.get_current_validator_state(
validator_info=validator_info,
consensus_state=consensus_state,
block_cache=self._block_cache)
poet_config_view = PoetConfigView(state_view)
# 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.
key_block_claim_limit = poet_config_view.key_block_claim_limit
if validator_state.poet_public_key == \
PoetBlockPublisher._poet_public_key and \
validator_state.key_block_claim_count >= \
key_block_claim_limit:
# 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[
PoetBlockPublisher._poet_public_key]
if not poet_key_state.has_been_refreshed:
LOGGER.info(
'Reached block claim limit (%d) for key for key: %s...%s',
key_block_claim_limit,
PoetBlockPublisher._poet_public_key[:8],
PoetBlockPublisher._poet_public_key[-8:])
sealed_signup_data = poet_key_state.sealed_signup_data
self._poet_key_state_store[
PoetBlockPublisher._poet_public_key] = \
PoetKeyState(
sealed_signup_data=sealed_signup_data,
has_been_refreshed=True)
self._register_signup_information(
block_header=block_header,
poet_enclave_module=poet_enclave_module)
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).
# While having a block claim delay is nice, it turns out that in
# practice the claim delay should not be more than one less than
# the number of validators. It helps to imagine the scenario
# where each validator hits their block claim limit in sequential
# blocks and their new validator registry information is updated
# in the following block by another validator, assuming that there
# were no forks. If there are N validators, once all N validators
# have updated their validator registry information, there will
# have been N-1 block commits and the Nth validator will only be
# able to get its updated validator registry information updated
# if the first validator that kicked this off is now able to claim
# a block. If the block claim delay was greater than or equal to
# the number of validators, at this point no validators would be
# able to claim a block.
number_of_validators = \
len(validator_registry_view.get_validators())
block_claim_delay = \
min(
poet_config_view.block_claim_delay,
number_of_validators - 1)
# While a validator network is starting up, we need to be careful
# about applying the block claim delay because if we are too
# aggressive we will get ourselves into a situation where the
# block claim delay will prevent any validators from claiming
# blocks. So, until we get at least block_claim_delay blocks
# we are going to choose not to enforce the delay.
if consensus_state.total_block_claim_count > block_claim_delay:
blocks_since_registration = \
block_header.block_num - \
validator_state.commit_block_number - 1
if block_claim_delay > blocks_since_registration:
return False
# Create a list of certificates for the wait timer. This seems to
# have a little too much knowledge of the WaitTimer implementation,
# but there is no use getting more than
# WaitTimer.certificate_sample_length wait certificates.
certificates = \
utils.build_certificate_list(
block_header=block_header,
block_cache=self._block_cache,
poet_enclave_module=poet_enclave_module,
maximum_number=WaitTimer.certificate_sample_length)
# 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
self._wait_timer = \
WaitTimer.create_wait_timer(
poet_enclave_module=poet_enclave_module,
validator_address=block_header.signer_pubkey,
certificates=list(certificates))
LOGGER.debug('Created wait timer: %s', self._wait_timer)
return True
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_pubkey
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)
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)
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:])
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
self._poet_key_state_store[active_poet_public_key] = \
PoetKeyState(
sealed_signup_data=sealed_signup_data,
has_been_refreshed=True)
# 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_pubkey,
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)
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_pubkey)
except KeyError:
LOGGER.error(
'Block %s rejected: Received block from an unregistered '
'validator %s...%s',
block_wrapper.identifier[:8],
block_wrapper.header.signer_pubkey[:8],
block_wrapper.header.signer_pubkey[-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_config_view = PoetConfigView(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_config_view=poet_config_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_config_view=poet_config_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 bock
# limit for its current PoET key pair.
if consensus_state.validator_has_claimed_block_limit(
validator_info=validator_info,
poet_config_view=poet_config_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_config_view=poet_config_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_config_view=poet_config_view,
population_estimate=wait_certificate.population_estimate(
poet_config_view=poet_config_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
def consensus_state_for_block_id(block_id, block_cache, state_view_factory,
consensus_state_store,
poet_enclave_module):
"""Returns the consensus state for the block referenced by block ID,
creating it from the consensus state history if necessary.
Args:
block_id (str): The ID of the block for which consensus state will
be returned.
block_cache (BlockCache): The block store cache
state_view_factory (StateViewFactory): A factory that can be used
to create state view object corresponding to blocks
consensus_state_store (ConsensusStateStore): The consensus state
store that is used to store interim consensus state created
up to resulting consensus state
poet_enclave_module (module): The PoET enclave module
Returns:
ConsensusState object representing the consensus state for the
block referenced by block_id
"""
consensus_state = None
previous_wait_certificate = None
blocks = collections.OrderedDict()
# Starting at the chain head, walk the block store backwards until we
# either get to the root or we get a block for which we have already
# created consensus state
current_id = block_id
while True:
block = \
ConsensusState._block_for_id(
block_id=current_id,
block_cache=block_cache)
if block is None:
break
# Try to fetch the consensus state. If that succeeds, we can
# stop walking back as we can now build on that consensus
# state.
consensus_state = consensus_state_store.get(block_id=current_id)
if consensus_state is not None:
break
wait_certificate = \
utils.deserialize_wait_certificate(
block=block,
poet_enclave_module=poet_enclave_module)
# If this is a PoET block (i.e., it has a wait certificate), get
# the validator info for the validator that signed this block and
# add the block information we will need to set validator state in
# the block's consensus state.
if wait_certificate is not None:
state_view = \
state_view_factory.create_view(
state_root_hash=block.state_root_hash)
validator_registry_view = \
ValidatorRegistryView(state_view=state_view)
validator_info = \
validator_registry_view.get_validator_info(
validator_id=block.header.signer_pubkey)
LOGGER.debug(
'We need to build consensus state for block: %s...%s',
current_id[:8], current_id[-8:])
blocks[current_id] = \
ConsensusState._BlockInfo(
wait_certificate=wait_certificate,
validator_info=validator_info,
poet_settings_view=PoetSettingsView(state_view))
# Otherwise, this is a non-PoET block. If we don't have any blocks
# yet or the last block we processed was a PoET block, put a
# placeholder in the list so that when we get to it we know that we
# need to reset the statistics.
elif not blocks or previous_wait_certificate is not None:
blocks[current_id] = \
ConsensusState._BlockInfo(
wait_certificate=None,
validator_info=None,
poet_settings_view=None)
previous_wait_certificate = wait_certificate
# Move to the previous block
current_id = block.previous_block_id
# At this point, if we have not found any consensus state, we need to
# create default state from which we can build upon
if consensus_state is None:
consensus_state = ConsensusState()
# Now, walk through the blocks for which we were supposed to create
# consensus state, from oldest to newest (i.e., in the reverse order in
# which they were added), and store state for PoET blocks so that the
# next time we don't have to walk so far back through the block chain.
for current_id, block_info in reversed(blocks.items()):
# If the block was not a PoET block (i.e., didn't have a wait
# certificate), reset the consensus state statistics. We are not
# going to store this in the consensus state store, but we will use
# it as the starting for the next PoET block.
if block_info.wait_certificate is None:
consensus_state = ConsensusState()
# Otherwise, let the consensus state update itself appropriately
# based upon the validator claiming a block, and then associate the
# consensus state with the new block in the store.
# validator state for the validator which claimed the block, create
# updated validator state for the validator, set/update the
# validator state in the consensus state object, and then associate
# the consensus state with the corresponding block in the consensus
# state store.
else:
consensus_state.validator_did_claim_block(
validator_info=block_info.validator_info,
wait_certificate=block_info.wait_certificate,
poet_settings_view=block_info.poet_settings_view)
consensus_state_store[current_id] = consensus_state
LOGGER.debug('Create consensus state: BID=%s, ALM=%f, TBCC=%d',
current_id[:8],
consensus_state.aggregate_local_mean,
consensus_state.total_block_claim_count)
return consensus_state
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)
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_pubkey)
except KeyError:
LOGGER.error(
'Block %s rejected: Received block from an unregistered '
'validator %s...%s',
block_wrapper.identifier[:8],
block_wrapper.header.signer_pubkey[:8],
block_wrapper.header.signer_pubkey[-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:])
# Create a list of certificates leading up to this block.
# This seems to have a little too much knowledge of the
# WaitTimer implementation, but there is no use getting more
# than WaitTimer.certificate_sample_length wait certificates.
certificates = \
utils.build_certificate_list(
block_header=block_wrapper.header,
block_cache=self._block_cache,
poet_enclave_module=poet_enclave_module,
maximum_number=WaitTimer.certificate_sample_length)
# 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
wait_certificate.check_valid(
poet_enclave_module=poet_enclave_module,
certificates=certificates,
poet_public_key=validator_info.signup_info.poet_public_key)
# Get the consensus state for the block that is being built upon and
# then fetch the validator state for this validator
consensus_state = \
utils.get_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)
validator_state = \
utils.get_current_validator_state(
validator_info=validator_info,
consensus_state=consensus_state,
block_cache=self._block_cache)
poet_config_view = PoetConfigView(state_view=state_view)
# Reject the block if the validator has already claimed the key bock
# limit for its current PoET key pair.
key_block_claim_limit = poet_config_view.key_block_claim_limit
if utils.validator_has_claimed_maximum_number_of_blocks(
validator_info=validator_info,
validator_state=validator_state,
key_block_claim_limit=key_block_claim_limit):
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 utils.validator_has_claimed_too_early(
validator_info=validator_info,
consensus_state=consensus_state,
block_number=block_wrapper.block_num,
validator_registry_view=validator_registry_view,
poet_config_view=poet_config_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 utils.validator_has_claimed_too_frequently(
validator_info=validator_info,
previous_block_id=block_wrapper.previous_block_id,
consensus_state=consensus_state,
poet_config_view=poet_config_view,
population_estimate=wait_certificate.population_estimate,
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
