async def validate_peer_status(chain: BaseBeaconChain,
peer_status: Status) -> None:
state_machine = chain.get_state_machine()
state = chain.get_head_state()
config = state_machine.config
if peer_status.head_fork_version != state.fork.current_version:
raise IrrelevantNetwork(
"`fork_version` mismatches: "
f"peer_status.head_fork_version={peer_status.head_fork_version}, "
f"state.fork.current_version={state.fork.current_version}")
# Can not validate the checkpoint with `finalized_epoch` higher than ours
if peer_status.finalized_epoch > state.finalized_checkpoint.epoch:
return
# Edge case where nothing is finalized yet
if (peer_status.finalized_epoch == 0
and peer_status.finalized_root == ZERO_ROOT):
return
finalized_epoch_start_slot = compute_start_slot_at_epoch(
peer_status.finalized_epoch,
config.SLOTS_PER_EPOCH,
)
finalized_root = chain.get_canonical_block_root(finalized_epoch_start_slot)
if peer_status.finalized_root != finalized_root:
raise IrrelevantNetwork(
"`finalized_root` mismatches: "
f"peer_status.finalized_root={peer_status.finalized_root.hex()}, "
f"peer_status.finalized_epoch={peer_status.finalized_epoch}, "
f"our `finalized_root` at the same `finalized_epoch`={finalized_root.hex()}"
)
def validate_start_slot(chain: BaseBeaconChain, start_slot: Slot) -> None:
config = chain.get_state_machine().config
state = chain.get_head_state()
finalized_epoch_start_slot = compute_start_slot_at_epoch(
epoch=state.finalized_checkpoint.epoch,
slots_per_epoch=config.SLOTS_PER_EPOCH,
)
if start_slot < finalized_epoch_start_slot:
raise ValidationError(
f"`start_slot`({start_slot}) lower than our"
f" latest finalized slot({finalized_epoch_start_slot})")