def get_allowed_signers_for_block_number(self, block_number):
# TODO take cached epoch hashes if block is of lastest epoch
prev_epoch_number = self.epoch.get_epoch_number(block_number) - 1
prev_epoch_start = self.epoch.get_epoch_start_block_number(
prev_epoch_number)
prev_epoch_end = self.epoch.get_epoch_end_block_number(
prev_epoch_number)
# this will extract every unconnected block in epoch, which is practically epoch hash
# TODO maybe consider blocks to be epoch hashes if they are in final round and consider everything else is orphan
epoch_hashes = self.dag.get_branches_for_timeslot_range(
prev_epoch_start, prev_epoch_end + 1)
if prev_epoch_number == 0:
epoch_hashes = [self.dag.genesis_block().get_hash()]
allowed_signers = []
for epoch_hash in epoch_hashes:
epoch_block_number = Epoch.convert_to_epoch_block_number(
block_number)
allowed_pubkey = self.permissions.get_sign_permission(
epoch_hash, epoch_block_number).public_key
allowed_signers.append(allowed_pubkey)
assert len(allowed_signers) > 0, "No signers allowed to sign block"
return allowed_signers
def try_to_sign_block(self, current_block_number):
epoch_block_number = Epoch.convert_to_epoch_block_number(
current_block_number)
allowed_to_sign = False
epoch_hashes = self.epoch.get_epoch_hashes()
for top, epoch_hash in epoch_hashes.items():
permission = self.permissions.get_sign_permission(
epoch_hash, epoch_block_number)
if permission.public_key == self.node_pubkey:
allowed_to_sign = True
break
if allowed_to_sign:
should_skip_maliciously = self.behaviour.is_malicious_skip_block()
# first_epoch_ever = self.epoch.get_epoch_number(current_block_number) == 1
if should_skip_maliciously: # and not first_epoch_ever: # skip first epoch check
self.epoch_private_keys.clear()
self.logger.info("Maliciously skiped block")
else:
if self.last_signed_block_number < current_block_number:
self.last_signed_block_number = current_block_number
self.sign_block(current_block_number)
else:
# skip once more block broadcast in same timeslot
pass
def try_to_send_negative_gossip(self, previous_timeslot_number):
if previous_timeslot_number not in self.dag.blocks_by_number:
epoch_block_number = Epoch.convert_to_epoch_block_number(
previous_timeslot_number)
allowed_to_send_negative_gossip = False
epoch_hashes = self.epoch.get_epoch_hashes()
for _, epoch_hash in epoch_hashes.items():
permissions = self.permissions.get_gossip_permission(
epoch_hash, epoch_block_number)
for permission in permissions:
if permission.public_key == self.node_pubkey:
allowed_to_send_negative_gossip = True
break
if allowed_to_send_negative_gossip:
self.broadcast_gossip_negative(previous_timeslot_number)
return True
return False
def get_allowed_signers_for_next_block(self, block):
current_block_number = self.epoch.get_current_timeframe_block_number()
epoch_block_number = Epoch.convert_to_epoch_block_number(
current_block_number)
if self.epoch.is_new_epoch_upcoming(current_block_number):
self.epoch.accept_tops_as_epoch_hashes()
epoch_hashes = self.epoch.get_epoch_hashes()
allowed_signers = []
for prev_hash in block.prev_hashes:
epoch_hash = None
if prev_hash in epoch_hashes:
epoch_hash = epoch_hashes[prev_hash]
else:
epoch_hash = self.epoch.find_epoch_hash_for_block(prev_hash)
if epoch_hash:
# self.logger.info("Calculating permissions from epoch_hash %s", epoch_hash.hex())
allowed_pubkey = self.permissions.get_sign_permission(
epoch_hash, epoch_block_number)
allowed_signers.append(allowed_pubkey)
assert len(
allowed_signers) > 0, "No signers allowed to sign next block"
return allowed_signers
