diff --git a/specs/core/0_beacon-chain.md b/specs/core/0_beacon-chain.md index 01c90670a..0b3a28d7a 100644 --- a/specs/core/0_beacon-chain.md +++ b/specs/core/0_beacon-chain.md @@ -26,7 +26,7 @@ - [`ProposerSlashing`](#proposerslashing) - [Attester slashings](#attester-slashings) - [`AttesterSlashing`](#attesterslashing) - - [`SlashableVote`](#slashablevote) + - [`SlashableAttestation`](#slashableattestation) - [Attestations](#attestations) - [`Attestation`](#attestation) - [`AttestationData`](#attestationdata) @@ -80,7 +80,7 @@ - [`get_domain`](#get_domain) - [`get_bitfield_bit`](#get_bitfield_bit) - [`verify_bitfield`](#verify_bitfield) - - [`verify_slashable_vote`](#verify_slashable_vote) + - [`verify_slashable_attestation`](#verify_slashable_attestation) - [`is_double_vote`](#is_double_vote) - [`is_surround_vote`](#is_surround_vote) - [`integer_squareroot`](#integer_squareroot) @@ -300,23 +300,23 @@ The following data structures are defined as [SimpleSerialize (SSZ)](https://git ```python { - # First batch of votes - 'slashable_vote_1': SlashableVote, - # Second batch of votes - 'slashable_vote_2': SlashableVote, + # First slashable attestation + 'slashable_attestation_1': SlashableAttestation, + # Second slashable attestation + 'slashable_attestation_2': SlashableAttestation, } ``` -##### `SlashableVote` +##### `SlashableAttestation` ```python { # Validator indices - 'validator_indices': '[uint64]', - # Custody bitfield - 'custody_bitfield': 'bytes', + 'validator_indices': ['uint64'], # Attestation data 'data': AttestationData, + # Custody bitfield + 'custody_bitfield': 'bytes', # Aggregate signature 'aggregate_signature': 'bytes96', } @@ -328,10 +328,10 @@ The following data structures are defined as [SimpleSerialize (SSZ)](https://git ```python { - # Attestation data - 'data': AttestationData, # Attester aggregation bitfield 'aggregation_bitfield': 'bytes', + # Attestation data + 'data': AttestationData, # Custody bitfield 'custody_bitfield': 'bytes', # BLS aggregate signature @@ -488,7 +488,6 @@ The following data structures are defined as [SimpleSerialize (SSZ)](https://git 'validator_registry': [Validator], 'validator_balances': ['uint64'], 'validator_registry_update_epoch': 'uint64', - 'validator_registry_exit_count': 'uint64', # Randomness and committees 'latest_randao_mixes': ['bytes32'], @@ -535,8 +534,6 @@ The following data structures are defined as [SimpleSerialize (SSZ)](https://git 'withdrawal_epoch': 'uint64', # Epoch when validator was penalized 'penalized_epoch': 'uint64', - # Exit counter when validator exited - 'exit_count': 'uint64', # Status flags 'status_flags': 'uint64', } @@ -557,14 +554,14 @@ The following data structures are defined as [SimpleSerialize (SSZ)](https://git ```python { - # Signed data - 'data': AttestationData, # Attester aggregation bitfield 'aggregation_bitfield': 'bytes', + # Attestation data + 'data': AttestationData, # Custody bitfield 'custody_bitfield': 'bytes', - # Slot the attestation was included - 'slot_included': 'uint64', + # Inclusion slot + 'inclusion_slot': 'uint64', } ``` @@ -636,6 +633,9 @@ Note: We aim to migrate to a S[T/N]ARK-friendly hash function in a future Ethere ```python def slot_to_epoch(slot: SlotNumber) -> EpochNumber: + """ + Return the epoch number of the given ``slot``. + """ return slot // EPOCH_LENGTH ``` @@ -643,6 +643,9 @@ def slot_to_epoch(slot: SlotNumber) -> EpochNumber: ```python def get_current_epoch(state: BeaconState) -> EpochNumber: + """ + Return the current epoch of the given ``state``. + """ return slot_to_epoch(state.slot) ``` @@ -650,6 +653,9 @@ def get_current_epoch(state: BeaconState) -> EpochNumber: ```python def get_epoch_start_slot(epoch: EpochNumber) -> SlotNumber: + """ + Return the starting slot of the given ``epoch``. + """ return epoch * EPOCH_LENGTH ``` @@ -657,7 +663,7 @@ def get_epoch_start_slot(epoch: EpochNumber) -> SlotNumber: ```python def is_active_validator(validator: Validator, epoch: EpochNumber) -> bool: """ - Checks if ``validator`` is active. + Check if ``validator`` is active. """ return validator.activation_epoch <= epoch < validator.exit_epoch ``` @@ -667,7 +673,7 @@ def is_active_validator(validator: Validator, epoch: EpochNumber) -> bool: ```python def get_active_validator_indices(validators: List[Validator], epoch: EpochNumber) -> List[ValidatorIndex]: """ - Gets indices of active validators from ``validators``. + Get indices of active validators from ``validators``. """ return [i for i, v in enumerate(validators) if is_active_validator(v, epoch)] ``` @@ -677,7 +683,7 @@ def get_active_validator_indices(validators: List[Validator], epoch: EpochNumber ```python def shuffle(values: List[Any], seed: Bytes32) -> List[Any]: """ - Returns the shuffled ``values`` with ``seed`` as entropy. + Return the shuffled ``values`` with ``seed`` as entropy. """ values_count = len(values) @@ -743,6 +749,9 @@ def split(values: List[Any], split_count: int) -> List[List[Any]]: ```python def get_epoch_committee_count(active_validator_count: int) -> int: + """ + Return the number of committees in one epoch. + """ return max( 1, min( @@ -759,8 +768,8 @@ def get_shuffling(seed: Bytes32, validators: List[Validator], epoch: EpochNumber) -> List[List[ValidatorIndex]] """ - Shuffles ``validators`` into crosslink committees seeded by ``seed`` and ``epoch``. - Returns a list of ``committees_per_epoch`` committees where each + Shuffle ``validators`` into crosslink committees seeded by ``seed`` and ``epoch``. + Return a list of ``committees_per_epoch`` committees where each committee is itself a list of validator indices. """ @@ -784,6 +793,9 @@ def get_shuffling(seed: Bytes32, ```python def get_previous_epoch_committee_count(state: BeaconState) -> int: + """ + Return the number of committees in the previous epoch of the given ``state``. + """ previous_active_validators = get_active_validator_indices( state.validator_registry, state.previous_calculation_epoch, @@ -795,6 +807,9 @@ def get_previous_epoch_committee_count(state: BeaconState) -> int: ```python def get_current_epoch_committee_count(state: BeaconState) -> int: + """ + Return the number of committees in the current epoch of the given ``state``. + """ current_active_validators = get_active_validator_indices( state.validator_registry, state.current_calculation_epoch, @@ -820,7 +835,7 @@ def get_crosslink_committees_at_slot(state: BeaconState, slot: SlotNumber, registry_change=False: bool) -> List[Tuple[List[ValidatorIndex], ShardNumber]]: """ - Returns the list of ``(committee, shard)`` tuples for the ``slot``. + Return the list of ``(committee, shard)`` tuples for the ``slot``. Note: There are two possible shufflings for crosslink committees for a ``slot`` in the next epoch -- with and without a `registry_change` @@ -884,7 +899,7 @@ def get_crosslink_committees_at_slot(state: BeaconState, def get_block_root(state: BeaconState, slot: SlotNumber) -> Bytes32: """ - Returns the block root at a recent ``slot``. + Return the block root at a recent ``slot``. """ assert state.slot <= slot + LATEST_BLOCK_ROOTS_LENGTH assert slot < state.slot @@ -899,7 +914,7 @@ def get_block_root(state: BeaconState, def get_randao_mix(state: BeaconState, epoch: EpochNumber) -> Bytes32: """ - Returns the randao mix at a recent ``epoch``. + Return the randao mix at a recent ``epoch``. """ assert get_current_epoch(state) - LATEST_RANDAO_MIXES_LENGTH < epoch <= get_current_epoch(state) return state.latest_randao_mixes[epoch % LATEST_RANDAO_MIXES_LENGTH] @@ -911,7 +926,7 @@ def get_randao_mix(state: BeaconState, def get_active_index_root(state: BeaconState, epoch: EpochNumber) -> Bytes32: """ - Returns the index root at a recent ``epoch``. + Return the index root at a recent ``epoch``. """ assert get_current_epoch(state) - LATEST_INDEX_ROOTS_LENGTH + ENTRY_EXIT_DELAY < epoch <= get_current_epoch(state) + ENTRY_EXIT_DELAY return state.latest_index_roots[epoch % LATEST_INDEX_ROOTS_LENGTH] @@ -938,7 +953,7 @@ def generate_seed(state: BeaconState, def get_beacon_proposer_index(state: BeaconState, slot: SlotNumber) -> ValidatorIndex: """ - Returns the beacon proposer index for the ``slot``. + Return the beacon proposer index for the ``slot``. """ first_committee, _ = get_crosslink_committees_at_slot(state, slot)[0] return first_committee[slot % len(first_committee)] @@ -965,7 +980,7 @@ def get_attestation_participants(state: BeaconState, attestation_data: AttestationData, bitfield: bytes) -> List[ValidatorIndex]: """ - Returns the participant indices at for the ``attestation_data`` and ``bitfield``. + Return the participant indices at for the ``attestation_data`` and ``bitfield``. """ # Find the committee in the list with the desired shard crosslink_committees = get_crosslink_committees_at_slot(state, attestation_data.slot) @@ -1006,7 +1021,7 @@ def is_power_of_two(value: int) -> bool: ```python def get_effective_balance(state: State, index: ValidatorIndex) -> Gwei: """ - Returns the effective balance (also known as "balance at stake") for a ``validator`` with the given ``index``. + Return the effective balance (also known as "balance at stake") for a ``validator`` with the given ``index``. """ return min(state.validator_balances[index], MAX_DEPOSIT_AMOUNT) ``` @@ -1016,6 +1031,9 @@ def get_effective_balance(state: State, index: ValidatorIndex) -> Gwei: ```python def get_fork_version(fork: Fork, epoch: EpochNumber) -> int: + """ + Return the fork version of the given ``epoch``. + """ if epoch < fork.epoch: return fork.previous_version else: @@ -1028,10 +1046,11 @@ def get_fork_version(fork: Fork, def get_domain(fork: Fork, epoch: EpochNumber, domain_type: int) -> int: - return get_fork_version( - fork, - epoch, - ) * 2**32 + domain_type + """ + Get the domain number that represents the fork meta and signature domain. + """ + fork_version = get_fork_version(fork, epoch) + return fork_version * 2**32 + domain_type ``` ### `get_bitfield_bit` @@ -1061,33 +1080,33 @@ def verify_bitfield(bitfield: bytes, committee_size: int) -> bool: return True ``` -### `verify_slashable_vote` +### `verify_slashable_attestation` ```python -def verify_slashable_vote(state: BeaconState, slashable_vote: SlashableVote) -> bool: +def verify_slashable_attestation(state: BeaconState, slashable_attestation: SlashableAttestation) -> bool: """ - Verify validity of ``slashable_vote`` fields. + Verify validity of ``slashable_attestation`` fields. """ - if slashable_vote.custody_bitfield != b'\x00' * len(slashable_vote.custody_bitfield): # [TO BE REMOVED IN PHASE 1] + if slashable_attestation.custody_bitfield != b'\x00' * len(slashable_attestation.custody_bitfield): # [TO BE REMOVED IN PHASE 1] return False - if len(slashable_vote.validator_indices) == 0: + if len(slashable_attestation.validator_indices) == 0: return False - for i in range(len(slashable_vote.validator_indices) - 1): - if slashable_vote.validator_indices[i] >= slashable_vote.validator_indices[i + 1]: + for i in range(len(slashable_attestation.validator_indices) - 1): + if slashable_attestation.validator_indices[i] >= slashable_attestation.validator_indices[i + 1]: return False - if not verify_bitfield(slashable_vote.custody_bitfield, len(slashable_vote.validator_indices)): + if not verify_bitfield(slashable_attestation.custody_bitfield, len(slashable_attestation.validator_indices)): return False - if len(slashable_vote.validator_indices) > MAX_INDICES_PER_SLASHABLE_VOTE: + if len(slashable_attestation.validator_indices) > MAX_INDICES_PER_SLASHABLE_VOTE: return False custody_bit_0_indices = [] custody_bit_1_indices = [] - for i, validator_index in enumerate(slashable_vote.validator_indices): - if get_bitfield_bit(slashable_vote.custody_bitfield, i) == 0b0: + for i, validator_index in enumerate(slashable_attestation.validator_indices): + if get_bitfield_bit(slashable_attestation.custody_bitfield, i) == 0b0: custody_bit_0_indices.append(validator_index) else: custody_bit_1_indices.append(validator_index) @@ -1098,10 +1117,10 @@ def verify_slashable_vote(state: BeaconState, slashable_vote: SlashableVote) -> bls_aggregate_pubkeys([state.validator_registry[i].pubkey for i in custody_bit_1_indices]), ], messages=[ - hash_tree_root(AttestationDataAndCustodyBit(attestation_data=slashable_vote.data, custody_bit=0b0)), - hash_tree_root(AttestationDataAndCustodyBit(attestation_data=slashable_vote.data, custody_bit=0b1)), + hash_tree_root(AttestationDataAndCustodyBit(data=slashable_attestation.data, custody_bit=0b0)), + hash_tree_root(AttestationDataAndCustodyBit(data=slashable_attestation.data, custody_bit=0b1)), ], - signature=slashable_vote.aggregate_signature, + signature=slashable_attestation.aggregate_signature, domain=get_domain( state.fork, slot_to_epoch(vote_data.data.slot), @@ -1114,11 +1133,9 @@ def verify_slashable_vote(state: BeaconState, slashable_vote: SlashableVote) -> ```python def is_double_vote(attestation_data_1: AttestationData, - attestation_data_2: AttestationData) -> bool + attestation_data_2: AttestationData) -> bool: """ - Assumes ``attestation_data_1`` is distinct from ``attestation_data_2``. - Returns True if the provided ``AttestationData`` are slashable - due to a 'double vote'. + Check if ``attestation_data_1`` and ``attestation_data_2`` have the same target. """ target_epoch_1 = slot_to_epoch(attestation_data_1.slot) target_epoch_2 = slot_to_epoch(attestation_data_2.slot) @@ -1131,11 +1148,7 @@ def is_double_vote(attestation_data_1: AttestationData, def is_surround_vote(attestation_data_1: AttestationData, attestation_data_2: AttestationData) -> bool: """ - Assumes ``attestation_data_1`` is distinct from ``attestation_data_2``. - Returns True if the provided ``AttestationData`` are slashable - due to a 'surround vote'. - Note: parameter order matters as this function only checks - that ``attestation_data_1`` surrounds ``attestation_data_2``. + Check if ``attestation_data_1`` surrounds ``attestation_data_2``. """ source_epoch_1 = attestation_data_1.justified_epoch source_epoch_2 = attestation_data_2.justified_epoch @@ -1191,6 +1204,9 @@ def validate_proof_of_possession(state: BeaconState, pubkey: BLSPubkey, proof_of_possession: BLSSignature, withdrawal_credentials: Bytes32) -> bool: + """ + Verify the given ``proof_of_possession``. + """ proof_of_possession_data = DepositInput( pubkey=pubkey, withdrawal_credentials=withdrawal_credentials, @@ -1242,7 +1258,6 @@ def process_deposit(state: BeaconState, exit_epoch=FAR_FUTURE_EPOCH, withdrawal_epoch=FAR_FUTURE_EPOCH, penalized_epoch=FAR_FUTURE_EPOCH, - exit_count=0, status_flags=0, ) @@ -1264,16 +1279,24 @@ Note: All functions in this section mutate `state`. #### `activate_validator` ```python -def activate_validator(state: BeaconState, index: ValidatorIndex, genesis: bool) -> None: +def activate_validator(state: BeaconState, index: ValidatorIndex, is_genesis: bool) -> None: + """ + Activate the validator of the given ``index``. + Note that this function mutates ``state``. + """ validator = state.validator_registry[index] - validator.activation_epoch = GENESIS_EPOCH if genesis else get_entry_exit_effect_epoch(get_current_epoch(state)) + validator.activation_epoch = GENESIS_EPOCH if is_genesis else get_entry_exit_effect_epoch(get_current_epoch(state)) ``` #### `initiate_validator_exit` ```python def initiate_validator_exit(state: BeaconState, index: ValidatorIndex) -> None: + """ + Initiate the validator of the given ``index``. + Note that this function mutates ``state``. + """ validator = state.validator_registry[index] validator.status_flags |= INITIATED_EXIT ``` @@ -1282,6 +1305,10 @@ def initiate_validator_exit(state: BeaconState, index: ValidatorIndex) -> None: ```python def exit_validator(state: BeaconState, index: ValidatorIndex) -> None: + """ + Exit the validator of the given ``index``. + Note that this function mutates ``state``. + """ validator = state.validator_registry[index] # The following updates only occur if not previous exited @@ -1289,15 +1316,16 @@ def exit_validator(state: BeaconState, index: ValidatorIndex) -> None: return validator.exit_epoch = get_entry_exit_effect_epoch(get_current_epoch(state)) - - state.validator_registry_exit_count += 1 - validator.exit_count = state.validator_registry_exit_count ``` #### `penalize_validator` ```python def penalize_validator(state: BeaconState, index: ValidatorIndex) -> None: + """ + Penalize the validator of the given ``index``. + Note that this function mutates ``state``. + """ exit_validator(state, index) validator = state.validator_registry[index] state.latest_penalized_balances[get_current_epoch(state) % LATEST_PENALIZED_EXIT_LENGTH] += get_effective_balance(state, index) @@ -1313,6 +1341,10 @@ def penalize_validator(state: BeaconState, index: ValidatorIndex) -> None: ```python def prepare_validator_for_withdrawal(state: BeaconState, index: ValidatorIndex) -> None: + """ + Set the validator with the given ``index`` with ``WITHDRAWABLE`` flag. + Note that this function mutates ``state``. + """ validator = state.validator_registry[index] validator.status_flags |= WITHDRAWABLE ``` @@ -1441,6 +1473,9 @@ A valid block with slot `GENESIS_SLOT` (a "genesis block") has the following val def get_initial_beacon_state(initial_validator_deposits: List[Deposit], genesis_time: int, latest_eth1_data: Eth1Data) -> BeaconState: + """ + Get the initial ``BeaconState``. + """ state = BeaconState( # Misc slot=GENESIS_SLOT, @@ -1455,7 +1490,6 @@ def get_initial_beacon_state(initial_validator_deposits: List[Deposit], validator_registry=[], validator_balances=[], validator_registry_update_epoch=GENESIS_EPOCH, - validator_registry_exit_count=0, # Randomness and committees latest_randao_mixes=[ZERO_HASH for _ in range(LATEST_RANDAO_MIXES_LENGTH)], @@ -1498,7 +1532,7 @@ def get_initial_beacon_state(initial_validator_deposits: List[Deposit], # Process initial activations for validator_index, _ in enumerate(state.validator_registry): if get_effective_balance(state, validator_index) >= MAX_DEPOSIT_AMOUNT: - activate_validator(state, validator_index, True) + activate_validator(state, validator_index, is_genesis=True) genesis_active_index_root = hash_tree_root(get_active_validator_indices(state, GENESIS_EPOCH)) for index in range(LATEST_INDEX_ROOTS_LENGTH): @@ -1539,6 +1573,9 @@ The beacon chain fork choice rule is a hybrid that combines justification and fi ```python def get_ancestor(store: Store, block: BeaconBlock, slot: SlotNumber) -> BeaconBlock: + """ + Get the ancestor of ``block`` with slot number ``slot``; return ``None`` if not found. + """ if block.slot == slot: return block elif block.slot < slot: @@ -1555,6 +1592,9 @@ def get_ancestor(store: Store, block: BeaconBlock, slot: SlotNumber) -> BeaconBl ```python def lmd_ghost(store: Store, start_state: BeaconState, start_block: BeaconBlock) -> BeaconBlock: + """ + Execute the LMD-GHOST algorithm to find the head ``BeaconBlock``. + """ validators = start_state.validator_registry active_validators = [ validators[i] @@ -1654,15 +1694,15 @@ Verify that `len(block.body.attester_slashings) <= MAX_ATTESTER_SLASHINGS`. For each `attester_slashing` in `block.body.attester_slashings`: -* Let `slashable_vote_1 = attester_slashing.slashable_vote_1`. -* Let `slashable_vote_2 = attester_slashing.slashable_vote_2`. -* Let `intersection = [x for x in slashable_vote_1.validator_indices if x in slashable_vote_2.validator_indices]`. -* Verify that `len(intersection) >= 1`. -* Verify that `slashable_vote_1.data != slashable_vote_2.data`. -* Verify that `is_double_vote(slashable_vote_1.data, slashable_vote_2.data)` or `is_surround_vote(slashable_vote_1.data, slashable_vote_2.data)`. -* Verify that `verify_slashable_vote(state, slashable_vote_1)`. -* Verify that `verify_slashable_vote(state, slashable_vote_2)`. -* For each [validator](#dfn-validator) index `i` in `intersection` run `penalize_validator(state, i)` if `state.validator_registry[i].penalized_epoch > get_current_epoch(state)`. +* Let `slashable_attestation_1 = attester_slashing.slashable_attestation_1`. +* Let `slashable_attestation_2 = attester_slashing.slashable_attestation_2`. +* Verify that `slashable_attestation_1.data != slashable_attestation_2.data`. +* Verify that `is_double_vote(slashable_attestation_1.data, slashable_attestation_2.data)` or `is_surround_vote(slashable_attestation_1.data, slashable_attestation_2.data)`. +* Verify that `verify_slashable_attestation(state, slashable_attestation_1)`. +* Verify that `verify_slashable_attestation(state, slashable_attestation_2)`. +* Let `slashable_indices = [index for index in slashable_attestation_1.validator_indices if index in slashable_attestation_2.validator_indices and state.validator_registry[index].penalized_epoch > get_current_epoch(state)]`. +* Verify that `len(slashable_indices) >= 1`. +* Run `penalize_validator(state, index)` for each `index` in `slashable_indices`. ##### Attestations @@ -1703,7 +1743,7 @@ For each `attestation` in `block.body.attestations`: ``` * [TO BE REMOVED IN PHASE 1] Verify that `attestation.data.shard_block_root == ZERO_HASH`. -* Append `PendingAttestation(data=attestation.data, aggregation_bitfield=attestation.aggregation_bitfield, custody_bitfield=attestation.custody_bitfield, slot_included=state.slot)` to `state.latest_attestations`. +* Append `PendingAttestation(data=attestation.data, aggregation_bitfield=attestation.aggregation_bitfield, custody_bitfield=attestation.custody_bitfield, inclusion_slot=state.slot)` to `state.latest_attestations`. ##### Deposits @@ -1719,6 +1759,9 @@ For each `deposit` in `block.body.deposits`: ```python def verify_merkle_branch(leaf: Bytes32, branch: List[Bytes32], depth: int, index: int, root: Bytes32) -> bool: + """ + Verify that the given ``leaf`` is on the merkle branch ``branch``. + """ value = leaf for i in range(depth): if index // (2**i) % 2: @@ -1804,8 +1847,8 @@ For every `slot in range(get_epoch_start_slot(previous_epoch), get_epoch_start_s Define the following helpers to process attestation inclusion rewards and inclusion distance reward/penalty. For every attestation `a` in `previous_epoch_attestations`: -* Let `inclusion_slot(state, index) = a.slot_included` for the attestation `a` where `index` is in `get_attestation_participants(state, a.data, a.aggregation_bitfield)`. If multiple attestations are applicable, the attestation with lowest `slot_included` is considered. -* Let `inclusion_distance(state, index) = a.slot_included - a.data.slot` where `a` is the above attestation. +* Let `inclusion_slot(state, index) = a.inclusion_slot` for the attestation `a` where `index` is in `get_attestation_participants(state, a.data, a.aggregation_bitfield)`. If multiple attestations are applicable, the attestation with lowest `inclusion_slot` is considered. +* Let `inclusion_distance(state, index) = a.inclusion_slot - a.data.slot` where `a` is the above attestation. #### Eth1 data @@ -1859,7 +1902,7 @@ Case 1: `epochs_since_finality <= 4`: * Expected FFG source: * Any [validator](#dfn-validator) `index` in `previous_epoch_justified_attester_indices` gains `base_reward(state, index) * previous_epoch_justified_attesting_balance // previous_total_balance`. - * Any [active validator](#dfn-active-validator) `v` not in `previous_epoch_justified_attester_indices` loses `base_reward(state, index)`. + * Any [active validator](#dfn-active-validator) `index` not in `previous_epoch_justified_attester_indices` loses `base_reward(state, index)`. * Expected FFG target: * Any [validator](#dfn-validator) `index` in `previous_epoch_boundary_attester_indices` gains `base_reward(state, index) * previous_epoch_boundary_attesting_balance // previous_total_balance`. * Any [active validator](#dfn-active-validator) `index` not in `previous_epoch_boundary_attester_indices` loses `base_reward(state, index)`. @@ -1948,7 +1991,7 @@ def update_validator_registry(state: BeaconState) -> None: break # Activate validator - activate_validator(state, index, False) + activate_validator(state, index, is_genesis=False) # Exit validators within the allowable balance churn balance_churn = 0 @@ -1985,17 +2028,21 @@ Regardless of whether or not a validator set change happens, run the following: ```python def process_penalties_and_exits(state: BeaconState) -> None: + """ + Process the penalties and prepare the validators who are eligible to withdrawal. + Note that this function mutates ``state``. + """ current_epoch = get_current_epoch(state) # The active validators active_validator_indices = get_active_validator_indices(state.validator_registry, current_epoch) # The total effective balance of active validators - total_balance = sum([get_effective_balance(state, i) for i in active_validator_indices]) + total_balance = sum(get_effective_balance(state, i) for i in active_validator_indices) for index, validator in enumerate(state.validator_registry): if current_epoch == validator.penalized_epoch + LATEST_PENALIZED_EXIT_LENGTH // 2: - e = current_epoch % LATEST_PENALIZED_EXIT_LENGTH - total_at_start = state.latest_penalized_balances[(e + 1) % LATEST_PENALIZED_EXIT_LENGTH] - total_at_end = state.latest_penalized_balances[e] + epoch_index = current_epoch % LATEST_PENALIZED_EXIT_LENGTH + total_at_start = state.latest_penalized_balances[(epoch_index + 1) % LATEST_PENALIZED_EXIT_LENGTH] + total_at_end = state.latest_penalized_balances[epoch_index] total_penalties = total_at_end - total_at_start penalty = get_effective_balance(state, index) * min(total_penalties * 3, total_balance) // total_balance state.validator_balances[index] -= penalty @@ -2010,7 +2057,8 @@ def process_penalties_and_exits(state: BeaconState) -> None: all_indices = list(range(len(state.validator_registry))) eligible_indices = filter(eligible, all_indices) - sorted_indices = sorted(eligible_indices, key=lambda index: state.validator_registry[index].exit_count) + # Sort in order of exit epoch, and validators that exit within the same epoch exit in order of validator index + sorted_indices = sorted(eligible_indices, key=lambda index: state.validator_registry[index].exit_epoch) withdrawn_so_far = 0 for index in sorted_indices: prepare_validator_for_withdrawal(state, index) diff --git a/specs/validator/0_beacon-chain-validator.md b/specs/validator/0_beacon-chain-validator.md index 0d3854e8f..d30fe3116 100644 --- a/specs/validator/0_beacon-chain-validator.md +++ b/specs/validator/0_beacon-chain-validator.md @@ -43,11 +43,11 @@ __NOTICE__: This document is a work-in-progress for researchers and implementers - [Epoch boundary root](#epoch-boundary-root) - [Shard block root](#shard-block-root) - [Latest crosslink root](#latest-crosslink-root) - - [Justified slot](#justified-slot) + - [Justified epoch](#justified-epoch) - [Justified block root](#justified-block-root) - [Construct attestation](#construct-attestation) - [Data](#data) - - [Participation bitfield](#participation-bitfield) + - [Aggregation bitfield](#aggregation-bitfield) - [Custody bitfield](#custody-bitfield) - [Aggregate signature](#aggregate-signature) - [Responsibility lookahead](#responsibility-lookahead) @@ -252,7 +252,7 @@ Set `attestation_data.slot = slot` where `slot` is the current slot of which the ##### Shard -Set `attestation_data.shard = shard` where `shard` is the shard associated with the validator's committee defined by `get_shard_committees_at_slot`. +Set `attestation_data.shard = shard` where `shard` is the shard associated with the validator's committee defined by `get_crosslink_committees_at_slot`. ##### Beacon block root @@ -274,15 +274,15 @@ _Note:_ This is a stub for phase 0. Set `attestation_data.latest_crosslink_root = state.latest_crosslinks[shard].shard_block_root` where `state` is the beacon state at `head` and `shard` is the validator's assigned shard. -##### Justified slot +##### Justified epoch -Set `attestation_data.justified_slot = state.justified_slot` where `state` is the beacon state at `head`. +Set `attestation_data.justified_epoch = state.justified_epoch` where `state` is the beacon state at `head`. ##### Justified block root -Set `attestation_data.justified_block_root = hash_tree_root(justified_block)` where `justified_block` is the block at `state.justified_slot` in the chain defined by `head`. +Set `attestation_data.justified_block_root = hash_tree_root(justified_block)` where `justified_block` is the block at `state.justified_epoch` in the chain defined by `head`. -_Note:_ This can be looked up in the state using `get_block_root(state, justified_slot)`. +_Note:_ This can be looked up in the state using `get_block_root(state, justified_epoch)`. #### Construct attestation @@ -292,7 +292,7 @@ Next the validator creates `attestation`, an [`Attestation`](https://github.com/ Set `attestation.data = attestation_data` where `attestation_data` is the `AttestationData` object defined in the previous section, [attestation data](#attestation-data). -##### Participation bitfield +##### Aggregation bitfield * Let `aggregation_bitfield` be a byte array filled with zeros of length `(len(committee) + 7) // 8`. * Let `index_into_committee` be the index into the validator's `committee` at which `validator_index` is located.