eth2.0-specs/tests/phase0/helpers.py

315 lines
9.5 KiB
Python

from copy import deepcopy
from py_ecc import bls
import build.phase0.spec as spec
from build.phase0.utils.minimal_ssz import signing_root
from build.phase0.spec import (
# constants
EMPTY_SIGNATURE,
ZERO_HASH,
# SSZ
Attestation,
AttestationData,
AttestationDataAndCustodyBit,
AttesterSlashing,
BeaconBlockHeader,
Deposit,
DepositData,
Eth1Data,
ProposerSlashing,
VoluntaryExit,
# functions
convert_to_indexed,
get_active_validator_indices,
get_attestation_participants,
get_block_root,
get_crosslink_committee_for_attestation,
get_crosslink_committees_at_slot,
get_current_epoch,
get_domain,
get_empty_block,
get_epoch_start_slot,
get_genesis_beacon_state,
slot_to_epoch,
verify_merkle_branch,
hash,
)
from build.phase0.utils.merkle_minimal import (
calc_merkle_tree_from_leaves,
get_merkle_proof,
get_merkle_root,
)
privkeys = [i + 1 for i in range(1000)]
pubkeys = [bls.privtopub(privkey) for privkey in privkeys]
pubkey_to_privkey = {pubkey: privkey for privkey, pubkey in zip(privkeys, pubkeys)}
def create_mock_genesis_validator_deposits(num_validators, deposit_data_leaves=None):
if not deposit_data_leaves:
deposit_data_leaves = []
proof_of_possession = b'\x33' * 96
deposit_data_list = []
for i in range(num_validators):
pubkey = pubkeys[i]
deposit_data = DepositData(
pubkey=pubkey,
# insecurely use pubkey as withdrawal key as well
withdrawal_credentials=spec.BLS_WITHDRAWAL_PREFIX_BYTE + hash(pubkey)[1:],
amount=spec.MAX_DEPOSIT_AMOUNT,
proof_of_possession=proof_of_possession,
)
item = hash(deposit_data.serialize())
deposit_data_leaves.append(item)
tree = calc_merkle_tree_from_leaves(tuple(deposit_data_leaves))
root = get_merkle_root((tuple(deposit_data_leaves)))
proof = list(get_merkle_proof(tree, item_index=i))
assert verify_merkle_branch(item, proof, spec.DEPOSIT_CONTRACT_TREE_DEPTH, i, root)
deposit_data_list.append(deposit_data)
genesis_validator_deposits = []
for i in range(num_validators):
genesis_validator_deposits.append(Deposit(
proof=list(get_merkle_proof(tree, item_index=i)),
index=i,
data=deposit_data_list[i]
))
return genesis_validator_deposits, root
def create_genesis_state(num_validators, deposit_data_leaves=None):
initial_deposits, deposit_root = create_mock_genesis_validator_deposits(
num_validators,
deposit_data_leaves,
)
return get_genesis_beacon_state(
initial_deposits,
genesis_time=0,
genesis_eth1_data=Eth1Data(
deposit_root=deposit_root,
deposit_count=len(initial_deposits),
block_hash=spec.ZERO_HASH,
),
)
def force_registry_change_at_next_epoch(state):
# artificially trigger registry update at next epoch transition
state.finalized_epoch = get_current_epoch(state) - 1
for crosslink in state.latest_crosslinks:
crosslink.epoch = state.finalized_epoch
state.validator_registry_update_epoch = state.finalized_epoch - 1
def build_empty_block_for_next_slot(state):
empty_block = get_empty_block()
empty_block.slot = state.slot + 1
previous_block_header = deepcopy(state.latest_block_header)
if previous_block_header.state_root == spec.ZERO_HASH:
previous_block_header.state_root = state.hash_tree_root()
empty_block.previous_block_root = signing_root(previous_block_header)
return empty_block
def build_deposit_data(state, pubkey, privkey, amount):
deposit_data = DepositData(
pubkey=pubkey,
# insecurely use pubkey as withdrawal key as well
withdrawal_credentials=spec.BLS_WITHDRAWAL_PREFIX_BYTE + hash(pubkey)[1:],
amount=amount,
proof_of_possession=EMPTY_SIGNATURE,
)
proof_of_possession = bls.sign(
message_hash=signing_root(deposit_data),
privkey=privkey,
domain=get_domain(
state.fork,
get_current_epoch(state),
spec.DOMAIN_DEPOSIT,
)
)
deposit_data.proof_of_possession = proof_of_possession
return deposit_data
def build_attestation_data(state, slot, shard):
assert state.slot >= slot
block_root = build_empty_block_for_next_slot(state).previous_block_root
epoch_start_slot = get_epoch_start_slot(get_current_epoch(state))
if epoch_start_slot == slot:
epoch_boundary_root = block_root
else:
get_block_root(state, epoch_start_slot)
if slot < epoch_start_slot:
justified_block_root = state.previous_justified_root
else:
justified_block_root = state.current_justified_root
return AttestationData(
slot=slot,
shard=shard,
beacon_block_root=block_root,
source_epoch=state.current_justified_epoch,
source_root=justified_block_root,
target_root=epoch_boundary_root,
crosslink_data_root=spec.ZERO_HASH,
previous_crosslink=deepcopy(state.latest_crosslinks[shard]),
)
def build_voluntary_exit(state, epoch, validator_index, privkey):
voluntary_exit = VoluntaryExit(
epoch=epoch,
validator_index=validator_index,
signature=EMPTY_SIGNATURE,
)
voluntary_exit.signature = bls.sign(
message_hash=signing_root(voluntary_exit),
privkey=privkey,
domain=get_domain(
fork=state.fork,
epoch=epoch,
domain_type=spec.DOMAIN_VOLUNTARY_EXIT,
)
)
return voluntary_exit
def build_deposit(state,
deposit_data_leaves,
pubkey,
privkey,
amount):
deposit_data = build_deposit_data(state, pubkey, privkey, amount)
item = hash(deposit_data.serialize())
index = len(deposit_data_leaves)
deposit_data_leaves.append(item)
tree = calc_merkle_tree_from_leaves(tuple(deposit_data_leaves))
root = get_merkle_root((tuple(deposit_data_leaves)))
proof = list(get_merkle_proof(tree, item_index=index))
assert verify_merkle_branch(item, proof, spec.DEPOSIT_CONTRACT_TREE_DEPTH, index, root)
deposit = Deposit(
proof=list(proof),
index=index,
data=deposit_data,
)
return deposit, root, deposit_data_leaves
def get_valid_proposer_slashing(state):
current_epoch = get_current_epoch(state)
validator_index = get_active_validator_indices(state.validator_registry, current_epoch)[-1]
privkey = pubkey_to_privkey[state.validator_registry[validator_index].pubkey]
slot = state.slot
header_1 = BeaconBlockHeader(
slot=slot,
previous_block_root=ZERO_HASH,
state_root=ZERO_HASH,
block_body_root=ZERO_HASH,
signature=EMPTY_SIGNATURE,
)
header_2 = deepcopy(header_1)
header_2.previous_block_root = b'\x02' * 32
header_2.slot = slot + 1
domain = get_domain(
fork=state.fork,
epoch=get_current_epoch(state),
domain_type=spec.DOMAIN_BEACON_BLOCK,
)
header_1.signature = bls.sign(
message_hash=signing_root(header_1),
privkey=privkey,
domain=domain,
)
header_2.signature = bls.sign(
message_hash=signing_root(header_2),
privkey=privkey,
domain=domain,
)
return ProposerSlashing(
proposer_index=validator_index,
header_1=header_1,
header_2=header_2,
)
def get_valid_attester_slashing(state):
attestation_1 = get_valid_attestation(state)
attestation_2 = deepcopy(attestation_1)
attestation_2.data.target_root = b'\x01'*32
return AttesterSlashing(
attestation_1=convert_to_indexed(state, attestation_1),
attestation_2=convert_to_indexed(state, attestation_2),
)
def get_valid_attestation(state, slot=None):
if slot is None:
slot = state.slot
shard = state.latest_start_shard
attestation_data = build_attestation_data(state, slot, shard)
crosslink_committee = get_crosslink_committee_for_attestation(state, attestation_data)
committee_size = len(crosslink_committee)
bitfield_length = (committee_size + 7) // 8
aggregation_bitfield = b'\xC0' + b'\x00' * (bitfield_length - 1)
custody_bitfield = b'\x00' * bitfield_length
attestation = Attestation(
aggregation_bitfield=aggregation_bitfield,
data=attestation_data,
custody_bitfield=custody_bitfield,
aggregate_signature=EMPTY_SIGNATURE,
)
participants = get_attestation_participants(
state,
attestation.data,
attestation.aggregation_bitfield,
)
assert len(participants) == 2
signatures = []
for validator_index in participants:
privkey = privkeys[validator_index]
signatures.append(
get_attestation_signature(
state,
attestation.data,
privkey
)
)
attestation.aggregation_signature = bls.aggregate_signatures(signatures)
return attestation
def get_attestation_signature(state, attestation_data, privkey, custody_bit=0b0):
message_hash = AttestationDataAndCustodyBit(
data=attestation_data,
custody_bit=custody_bit,
).hash_tree_root()
return bls.sign(
message_hash=message_hash,
privkey=privkey,
domain=get_domain(
fork=state.fork,
epoch=slot_to_epoch(attestation_data.slot),
domain_type=spec.DOMAIN_ATTESTATION,
)
)