def slash_validator(
state: BeaconState,
index: ValidatorIndex,
config: Eth2Config,
whistleblower_index: ValidatorIndex = None,
) -> BeaconState:
"""
Slash the validator with index ``index``.
Exit the validator, penalize the validator, and reward the whistleblower.
"""
# NOTE: remove in phase 1
assert whistleblower_index is None
slots_per_epoch = config.SLOTS_PER_EPOCH
current_epoch = state.current_epoch(slots_per_epoch)
state = initiate_validator_exit(state, index, config)
state = state.transform(
("validators", index),
partial(
_set_validator_slashed,
current_epoch=current_epoch,
epochs_per_slashings_vector=config.EPOCHS_PER_SLASHINGS_VECTOR,
),
)
slashed_balance = state.validators[index].effective_balance
slashed_epoch = current_epoch % config.EPOCHS_PER_SLASHINGS_VECTOR
state = state.transform(("slashings", slashed_epoch),
lambda balance: Gwei(balance + slashed_balance))
state = decrease_balance(
state, index, slashed_balance // config.MIN_SLASHING_PENALTY_QUOTIENT)
proposer_index = get_beacon_proposer_index(state, config)
if whistleblower_index is None:
whistleblower_index = proposer_index
whistleblower_reward = Gwei(slashed_balance //
config.WHISTLEBLOWER_REWARD_QUOTIENT)
proposer_reward = Gwei(whistleblower_reward //
config.PROPOSER_REWARD_QUOTIENT)
state = increase_balance(state, proposer_index, proposer_reward)
state = increase_balance(state, whistleblower_index,
Gwei(whistleblower_reward - proposer_reward))
return state
def process_randao(state: BeaconState, block: BaseBeaconBlock,
config: Eth2Config) -> BeaconState:
proposer_index = get_beacon_proposer_index(
state=state, committee_config=CommitteeConfig(config))
epoch = state.current_epoch(config.SLOTS_PER_EPOCH)
validate_randao_reveal(
state=state,
proposer_index=proposer_index,
epoch=epoch,
randao_reveal=block.body.randao_reveal,
slots_per_epoch=config.SLOTS_PER_EPOCH,
)
randao_mix_index = epoch % config.EPOCHS_PER_HISTORICAL_VECTOR
new_randao_mix = bitwise_xor(
get_randao_mix(
state=state,
epoch=epoch,
epochs_per_historical_vector=config.EPOCHS_PER_HISTORICAL_VECTOR,
),
hash_eth2(block.body.randao_reveal),
)
return state.transform(("randao_mixes", randao_mix_index), new_randao_mix)
def initiate_validator_exit(state: BeaconState, index: ValidatorIndex,
config: Eth2Config) -> BeaconState:
"""
Initiate exit for the validator with the given ``index``.
Return the updated state (immutable).
"""
return state.transform(
("validators", index),
partial(initiate_exit_for_validator, state=state, config=config),
)
def _process_activation_eligibility_or_ejections(
state: BeaconState, index: ValidatorIndex,
config: Eth2Config) -> BeaconState:
current_epoch = state.current_epoch(config.SLOTS_PER_EPOCH)
validator = state.validators[index]
if validator.is_eligible_for_activation_queue(config):
validator = validator.set("activation_eligibility_epoch",
current_epoch + 1)
if (validator.is_active(current_epoch)
and validator.effective_balance <= config.EJECTION_BALANCE):
validator = initiate_exit_for_validator(validator, state, config)
return state.transform(("validators", index), validator)
def _process_slot(state: BeaconState, config: Eth2Config) -> BeaconState:
slots_per_historical_root = config.SLOTS_PER_HISTORICAL_ROOT
previous_state_root = state.hash_tree_root
updated_state_roots = _update_historical_root(state.state_roots,
state.slot,
slots_per_historical_root,
previous_state_root)
if state.latest_block_header.state_root == ZERO_HASH32:
state = state.transform(("latest_block_header", "state_root"),
previous_state_root)
updated_block_roots = _update_historical_root(
state.block_roots,
state.slot,
slots_per_historical_root,
state.latest_block_header.signing_root,
)
return state.mset("block_roots", updated_block_roots, "state_roots",
updated_state_roots)
def decrease_balance(state: BeaconState, index: ValidatorIndex,
delta: Gwei) -> BeaconState:
return state.transform(
("balances", index),
lambda balance: Gwei(0) if delta > balance else Gwei(balance - delta),
)
def increase_balance(state: BeaconState, index: ValidatorIndex,
delta: Gwei) -> BeaconState:
return state.transform(("balances", index),
lambda balance: Gwei(balance + delta))
def _mini_stf(state: BeaconState, block: Optional[BeaconBlock],
config: Eth2Config) -> BeaconState:
"""
A simplified state transition for testing state storage.
- updates ``state_roots`` with the previous slot's state root
- updates ``block_roots`` with the previous slot's block root
- updates ``randao_mixes`` with an arbitrary mix at the current epoch
- creates a new ``latest_block_header`` and adds it to the state
- fills in the rest of the attributes with arbitrary values
"""
current_slot = state.slot + 1
current_epoch = current_slot // config.SLOTS_PER_EPOCH
if block:
latest_block_header = block.header
else:
latest_block_header = state.latest_block_header
# state changes that depend on the previous state for retrieval
randao_mix = Root(Hash32(current_slot.to_bytes(32, byteorder="little")))
state = (state.transform(
("state_roots", state.slot % config.SLOTS_PER_HISTORICAL_ROOT),
state.hash_tree_root,
).transform(
("block_roots", state.slot % config.SLOTS_PER_HISTORICAL_ROOT),
state.latest_block_header.hash_tree_root,
).transform(
("randao_mixes", current_epoch % config.EPOCHS_PER_HISTORICAL_VECTOR),
randao_mix,
).mset("slot", current_slot, "latest_block_header", latest_block_header))
# state changes that do not depend on the previous state for retrieval
new_validators = [
Validator.create(pubkey=BLSPubkey(n.to_bytes(48, byteorder="little")))
for n in range(current_slot, current_slot + 20)
]
new_eth1_data_votes = [
Eth1Data.create(
deposit_root=Root(Hash32(n.to_bytes(32, byteorder="little"))))
for n in range(current_slot, current_slot + 7)
]
new_previous_epoch_attestations = [
PendingAttestation.create(proposer_index=ValidatorIndex(n))
for n in range(current_slot, current_slot + 5)
]
new_current_epoch_attestations = [
PendingAttestation.create(proposer_index=ValidatorIndex(n))
for n in range(current_slot + 5, current_slot + 10)
]
state = state.mset(
"validators",
new_validators,
"balances",
(32, ) * len(new_validators),
"eth1_data_votes",
new_eth1_data_votes,
"eth1_data",
new_eth1_data_votes[0],
"previous_epoch_attestations",
new_previous_epoch_attestations,
"current_epoch_attestations",
new_current_epoch_attestations,
"previous_justified_checkpoint",
Checkpoint.create(epoch=Epoch(current_slot + 42)),
"current_justified_checkpoint",
Checkpoint.create(epoch=Epoch(current_slot + 43)),
"finalized_checkpoint",
Checkpoint.create(epoch=Epoch(current_slot + 44)),
)
return state
