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Merge branch 'dev' into vbuterin-patch-3

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Danny Ryan 2019-03-26 13:30:33 -06:00
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1
.gitignore vendored
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@ -4,3 +4,4 @@
/.pytest_cache
build/
output/

236
specs/core/0_beacon-chain.md
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@ -29,7 +29,6 @@
- [`AttestationData`](#attestationdata)
- [`AttestationDataAndCustodyBit`](#attestationdataandcustodybit)
- [`StandaloneAttestation`](#standaloneattestation)
- [`DepositInput`](#depositinput)
- [`DepositData`](#depositdata)
- [`BeaconBlockHeader`](#beaconblockheader)
- [`Validator`](#validator)
@ -69,9 +68,7 @@
- [`get_split_offset`](#get_split_offset)
- [`get_epoch_committee_count`](#get_epoch_committee_count)
- [`compute_committee`](#compute_committee)
- [`get_previous_epoch_committee_count`](#get_previous_epoch_committee_count)
- [`get_current_epoch_committee_count`](#get_current_epoch_committee_count)
- [`get_next_epoch_committee_count`](#get_next_epoch_committee_count)
- [`get_crosslink_committees_at_slot`](#get_crosslink_committees_at_slot)
- [`get_block_root`](#get_block_root)
- [`get_state_root`](#get_state_root)
@ -81,7 +78,6 @@
- [`get_beacon_proposer_index`](#get_beacon_proposer_index)
- [`verify_merkle_branch`](#verify_merkle_branch)
- [`get_attestation_participants`](#get_attestation_participants)
- [`is_power_of_two`](#is_power_of_two)
- [`int_to_bytes1`, `int_to_bytes2`, ...](#int_to_bytes1-int_to_bytes2-)
- [`bytes_to_int`](#bytes_to_int)
- [`get_effective_balance`](#get_effective_balance)
@ -238,6 +234,10 @@ Code snippets appearing in `this style` are to be interpreted as Python code.
| `SLOTS_PER_HISTORICAL_ROOT` | `2**13` (= 8,192) | slots | ~13 hours |
| `MIN_VALIDATOR_WITHDRAWABILITY_DELAY` | `2**8` (= 256) | epochs | ~27 hours |
| `PERSISTENT_COMMITTEE_PERIOD` | `2**11` (= 2,048) | epochs | 9 days |
| `MAX_CROSSLINK_EPOCHS` | `2**6` (= 64) |
* `MAX_CROSSLINK_EPOCHS` should be a small constant times `SHARD_COUNT // SLOTS_PER_EPOCH`
### State list lengths
@ -385,7 +385,7 @@ The types are defined topologically to aid in facilitating an executable version
}
```
#### `DepositInput`
#### `DepositData`
```python
{
@ -393,21 +393,10 @@ The types are defined topologically to aid in facilitating an executable version
'pubkey': 'bytes48',
# Withdrawal credentials
'withdrawal_credentials': 'bytes32',
# A BLS signature of this `DepositInput`
'proof_of_possession': 'bytes96',
}
```
#### `DepositData`
```python
{
# Amount in Gwei
'amount': 'uint64',
# Timestamp from deposit contract
'timestamp': 'uint64',
# Deposit input
'deposit_input': DepositInput,
# Container self-signature
'proof_of_possession': 'bytes96',
}
```
@ -521,7 +510,7 @@ The types are defined topologically to aid in facilitating an executable version
# Index in the deposit tree
'index': 'uint64',
# Data
'deposit_data': DepositData,
'data': DepositData,
}
```
@ -607,12 +596,7 @@ The types are defined topologically to aid in facilitating an executable version
# Randomness and committees
'latest_randao_mixes': ['bytes32', LATEST_RANDAO_MIXES_LENGTH],
'previous_shuffling_start_shard': 'uint64',
'current_shuffling_start_shard': 'uint64',
'previous_shuffling_epoch': 'uint64',
'current_shuffling_epoch': 'uint64',
'previous_shuffling_seed': 'bytes32',
'current_shuffling_seed': 'bytes32',
'latest_start_shard': 'uint64',
# Finality
'previous_epoch_attestations': [PendingAttestation],
@ -669,7 +653,7 @@ def xor(bytes1: Bytes32, bytes2: Bytes32) -> Bytes32:
### `hash`
The hash function is denoted by `hash`. In Phase 0 the beacon chain is deployed with the same hash function as Ethereum 1.0, i.e. Keccak-256 (also incorrectly known as SHA3).
The `hash` function is SHA256.
Note: We aim to migrate to a S[T/N]ARK-friendly hash function in a future Ethereum 2.0 deployment phase.
@ -693,7 +677,8 @@ def get_temporary_block_header(block: BeaconBlock) -> BeaconBlockHeader:
previous_block_root=block.previous_block_root,
state_root=ZERO_HASH,
block_body_root=hash_tree_root(block.body),
signature=block.signature,
# signed_root(block) is used for block id purposes so signature is a stub
signature=EMPTY_SIGNATURE,
)
```
@ -889,20 +874,6 @@ def compute_committee(validator_indices: List[ValidatorIndex],
**Note**: this definition and the next few definitions are highly inefficient as algorithms as they re-calculate many sub-expressions. Production implementations are expected to appropriately use caching/memoization to avoid redoing work.
### `get_previous_epoch_committee_count`
```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_shuffling_epoch,
)
return get_epoch_committee_count(len(previous_active_validators))
```
### `get_current_epoch_committee_count`
```python
@ -912,36 +883,18 @@ def get_current_epoch_committee_count(state: BeaconState) -> int:
"""
current_active_validators = get_active_validator_indices(
state.validator_registry,
state.current_shuffling_epoch,
get_current_epoch(state),
)
return get_epoch_committee_count(len(current_active_validators))
```
### `get_next_epoch_committee_count`
```python
def get_next_epoch_committee_count(state: BeaconState) -> int:
"""
Return the number of committees in the next epoch of the given ``state``.
"""
next_active_validators = get_active_validator_indices(
state.validator_registry,
get_current_epoch(state) + 1,
)
return get_epoch_committee_count(len(next_active_validators))
```
### `get_crosslink_committees_at_slot`
```python
def get_crosslink_committees_at_slot(state: BeaconState,
slot: Slot,
registry_change: bool=False) -> List[Tuple[List[ValidatorIndex], Shard]]:
slot: Slot) -> List[Tuple[List[ValidatorIndex], Shard]]:
"""
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`
"""
epoch = slot_to_epoch(slot)
current_epoch = get_current_epoch(state)
@ -949,40 +902,24 @@ def get_crosslink_committees_at_slot(state: BeaconState,
next_epoch = current_epoch + 1
assert previous_epoch <= epoch <= next_epoch
indices = get_active_validator_indices(
state.validator_registry,
epoch,
)
committees_per_epoch = get_epoch_committee_count(len(indices))
if epoch == current_epoch:
committees_per_epoch = get_current_epoch_committee_count(state)
seed = state.current_shuffling_seed
shuffling_epoch = state.current_shuffling_epoch
shuffling_start_shard = state.current_shuffling_start_shard
start_shard = state.latest_start_shard
elif epoch == previous_epoch:
committees_per_epoch = get_previous_epoch_committee_count(state)
seed = state.previous_shuffling_seed
shuffling_epoch = state.previous_shuffling_epoch
shuffling_start_shard = state.previous_shuffling_start_shard
start_shard = (state.latest_start_shard - committees_per_epoch) % SHARD_COUNT
elif epoch == next_epoch:
epochs_since_last_registry_update = current_epoch - state.validator_registry_update_epoch
if registry_change:
committees_per_epoch = get_next_epoch_committee_count(state)
seed = generate_seed(state, next_epoch)
shuffling_epoch = next_epoch
current_committees_per_epoch = get_current_epoch_committee_count(state)
shuffling_start_shard = (state.current_shuffling_start_shard + current_committees_per_epoch) % SHARD_COUNT
elif epochs_since_last_registry_update > 1 and is_power_of_two(epochs_since_last_registry_update):
committees_per_epoch = get_next_epoch_committee_count(state)
seed = generate_seed(state, next_epoch)
shuffling_epoch = next_epoch
shuffling_start_shard = state.current_shuffling_start_shard
else:
committees_per_epoch = get_current_epoch_committee_count(state)
seed = state.current_shuffling_seed
shuffling_epoch = state.current_shuffling_epoch
shuffling_start_shard = state.current_shuffling_start_shard
current_epoch_committees = get_current_epoch_committee_count(state)
start_shard = (state.latest_start_shard + current_epoch_committees) % SHARD_COUNT
indices = get_active_validator_indices(state.validator_registry, shuffling_epoch)
committees_per_slot = committees_per_epoch // SLOTS_PER_EPOCH
offset = slot % SLOTS_PER_EPOCH
slot_start_shard = (shuffling_start_shard + committees_per_slot * offset) % SHARD_COUNT
slot_start_shard = (start_shard + committees_per_slot * offset) % SHARD_COUNT
seed = generate_seed(state, epoch)
return [
(
@ -1061,20 +998,26 @@ def generate_seed(state: BeaconState,
```python
def get_beacon_proposer_index(state: BeaconState,
slot: Slot,
registry_change: bool=False) -> ValidatorIndex:
slot: Slot) -> ValidatorIndex:
"""
Return the beacon proposer index for the ``slot``.
Due to proposer selection being based upon the validator balances during
the epoch in question, this can only be run for the current epoch.
"""
epoch = slot_to_epoch(slot)
current_epoch = get_current_epoch(state)
previous_epoch = get_previous_epoch(state)
next_epoch = current_epoch + 1
assert slot_to_epoch(slot) == current_epoch
assert previous_epoch <= epoch <= next_epoch
first_committee, _ = get_crosslink_committees_at_slot(state, slot, registry_change)[0]
return first_committee[epoch % len(first_committee)]
first_committee, _ = get_crosslink_committees_at_slot(state, slot)[0]
i = 0
while True:
rand_byte = hash(
generate_seed(state, current_epoch) +
int_to_bytes8(i // 32)
)[i % 32]
candidate = first_committee[(current_epoch + i) % len(first_committee)]
if get_effective_balance(state, candidate) * 256 > MAX_DEPOSIT_AMOUNT * rand_byte:
return candidate
i += 1
```
### `verify_merkle_branch`
@ -1120,16 +1063,6 @@ def get_attestation_participants(state: BeaconState,
return sorted(participants)
```
### `is_power_of_two`
```python
def is_power_of_two(value: int) -> bool:
"""
Check if ``value`` is a power of two integer.
"""
return (value > 0) and (value & (value - 1) == 0)
```
### `int_to_bytes1`, `int_to_bytes2`, ...
`int_to_bytes1(x): return x.to_bytes(1, 'little')`, `int_to_bytes2(x): return x.to_bytes(2, 'little')`, and so on for all integers, particularly 1, 2, 3, 4, 8, 32, 48, 96.
@ -1348,19 +1281,12 @@ def process_deposit(state: BeaconState, deposit: Deposit) -> None:
Process a deposit from Ethereum 1.0.
Note that this function mutates ``state``.
"""
deposit_input = deposit.deposit_data.deposit_input
# Should equal 8 bytes for deposit_data.amount +
# 8 bytes for deposit_data.timestamp +
# 176 bytes for deposit_data.deposit_input
# It should match the deposit_data in the eth1.0 deposit contract
serialized_deposit_data = serialize(deposit.deposit_data)
# Deposits must be processed in order
assert deposit.index == state.deposit_index
# Verify the Merkle branch
merkle_branch_is_valid = verify_merkle_branch(
leaf=hash(serialized_deposit_data),
leaf=hash(serialize(deposit.data)), # 48 + 32 + 8 + 96 = 184 bytes serialization
proof=deposit.proof,
depth=DEPOSIT_CONTRACT_TREE_DEPTH,
index=deposit.index,
@ -1375,16 +1301,15 @@ def process_deposit(state: BeaconState, deposit: Deposit) -> None:
state.deposit_index += 1
validator_pubkeys = [v.pubkey for v in state.validator_registry]
pubkey = deposit_input.pubkey
amount = deposit.deposit_data.amount
withdrawal_credentials = deposit_input.withdrawal_credentials
pubkey = deposit.data.pubkey
amount = deposit.data.amount
if pubkey not in validator_pubkeys:
# Verify the proof of possession
proof_is_valid = bls_verify(
pubkey=deposit_input.pubkey,
message_hash=signed_root(deposit_input),
signature=deposit_input.proof_of_possession,
pubkey=pubkey,
message_hash=signed_root(deposit.data),
signature=deposit.data.proof_of_possession,
domain=get_domain(
state.fork,
get_current_epoch(state),
@ -1397,7 +1322,7 @@ def process_deposit(state: BeaconState, deposit: Deposit) -> None:
# Add new validator
validator = Validator(
pubkey=pubkey,
withdrawal_credentials=withdrawal_credentials,
withdrawal_credentials=deposit.data.withdrawal_credentials,
activation_epoch=FAR_FUTURE_EPOCH,
exit_epoch=FAR_FUTURE_EPOCH,
withdrawable_epoch=FAR_FUTURE_EPOCH,
@ -1499,11 +1424,11 @@ The initial deployment phases of Ethereum 2.0 are implemented without consensus
### Deposit arguments
The deposit contract has a single `deposit` function which takes as argument a SimpleSerialize'd `DepositInput`.
The deposit contract has a single `deposit` function which takes as argument a SimpleSerialize'd `DepositData`.
### Withdrawal credentials
One of the `DepositInput` fields is `withdrawal_credentials`. It is a commitment to credentials for withdrawals to shards. The first byte of `withdrawal_credentials` is a version number. As of now the only expected format is as follows:
One of the `DepositData` fields is `withdrawal_credentials`. It is a commitment to credentials for withdrawals to shards. The first byte of `withdrawal_credentials` is a version number. As of now the only expected format is as follows:
* `withdrawal_credentials[:1] == BLS_WITHDRAWAL_PREFIX_BYTE`
* `withdrawal_credentials[1:] == hash(withdrawal_pubkey)[1:]` where `withdrawal_pubkey` is a BLS pubkey
@ -1601,12 +1526,7 @@ def get_genesis_beacon_state(genesis_validator_deposits: List[Deposit],
# Randomness and committees
latest_randao_mixes=Vector([ZERO_HASH for _ in range(LATEST_RANDAO_MIXES_LENGTH)]),
previous_shuffling_start_shard=GENESIS_START_SHARD,
current_shuffling_start_shard=GENESIS_START_SHARD,
previous_shuffling_epoch=GENESIS_EPOCH - 1,
current_shuffling_epoch=GENESIS_EPOCH,
previous_shuffling_seed=ZERO_HASH,
current_shuffling_seed=ZERO_HASH,
latest_start_shard=GENESIS_START_SHARD,
# Finality
previous_epoch_attestations=[],
@ -1646,7 +1566,6 @@ def get_genesis_beacon_state(genesis_validator_deposits: List[Deposit],
genesis_active_index_root = hash_tree_root(get_active_validator_indices(state.validator_registry, GENESIS_EPOCH))
for index in range(LATEST_ACTIVE_INDEX_ROOTS_LENGTH):
state.latest_active_index_roots[index] = genesis_active_index_root
state.current_shuffling_seed = generate_seed(state, GENESIS_EPOCH)
return state
```
@ -1764,7 +1683,7 @@ def cache_state(state: BeaconState) -> None:
state.latest_block_header.state_root = previous_slot_state_root
# store latest known block for previous slot
state.latest_block_roots[state.slot % SLOTS_PER_HISTORICAL_ROOT] = hash_tree_root(state.latest_block_header)
state.latest_block_roots[state.slot % SLOTS_PER_HISTORICAL_ROOT] = signed_root(state.latest_block_header)
```
### Per-epoch processing
@ -1921,7 +1840,7 @@ Run the following function:
```python
def process_crosslinks(state: BeaconState) -> None:
current_epoch = get_current_epoch(state)
previous_epoch = current_epoch - 1
previous_epoch = max(current_epoch - 1, GENESIS_EPOCH)
next_epoch = current_epoch + 1
for slot in range(get_epoch_start_slot(previous_epoch), get_epoch_start_slot(next_epoch)):
for crosslink_committee, shard in get_crosslink_committees_at_slot(state, slot):
@ -1930,7 +1849,7 @@ def process_crosslinks(state: BeaconState) -> None:
total_balance = get_total_balance(state, crosslink_committee)
if 3 * participating_balance >= 2 * total_balance:
state.latest_crosslinks[shard] = Crosslink(
epoch=slot_to_epoch(slot),
epoch=min(slot_to_epoch(slot), state.latest_crosslinks[shard].epoch + MAX_CROSSLINK_EPOCHS),
crosslink_data_root=winning_root
)
```
@ -2130,22 +2049,6 @@ def process_ejections(state: BeaconState) -> None:
#### Validator registry and shuffling seed data
```python
def should_update_validator_registry(state: BeaconState) -> bool:
# Must have finalized a new block
if state.finalized_epoch <= state.validator_registry_update_epoch:
return False
# Must have processed new crosslinks on all shards of the current epoch
shards_to_check = [
(state.current_shuffling_start_shard + i) % SHARD_COUNT
for i in range(get_current_epoch_committee_count(state))
]
for shard in shards_to_check:
if state.latest_crosslinks[shard].epoch <= state.validator_registry_update_epoch:
return False
return True
```
```python
def update_validator_registry(state: BeaconState) -> None:
"""
@ -2199,30 +2102,14 @@ def update_validator_registry(state: BeaconState) -> None:
Run the following function:
```python
def update_registry_and_shuffling_data(state: BeaconState) -> None:
# First set previous shuffling data to current shuffling data
state.previous_shuffling_epoch = state.current_shuffling_epoch
state.previous_shuffling_start_shard = state.current_shuffling_start_shard
state.previous_shuffling_seed = state.current_shuffling_seed
current_epoch = get_current_epoch(state)
next_epoch = current_epoch + 1
def update_registry(state: BeaconState) -> None:
# Check if we should update, and if so, update
if should_update_validator_registry(state):
if state.finalized_epoch > state.validator_registry_update_epoch:
update_validator_registry(state)
# If we update the registry, update the shuffling data and shards as well
state.current_shuffling_epoch = next_epoch
state.current_shuffling_start_shard = (
state.current_shuffling_start_shard +
get_current_epoch_committee_count(state) % SHARD_COUNT
)
state.current_shuffling_seed = generate_seed(state, state.current_shuffling_epoch)
else:
# If processing at least one crosslink keeps failing, then reshuffle every power of two,
# but don't update the current_shuffling_start_shard
epochs_since_last_registry_update = current_epoch - state.validator_registry_update_epoch
if epochs_since_last_registry_update > 1 and is_power_of_two(epochs_since_last_registry_update):
state.current_shuffling_epoch = next_epoch
state.current_shuffling_seed = generate_seed(state, state.current_shuffling_epoch)
state.latest_start_shard = (
state.latest_start_shard +
get_current_epoch_committee_count(state)
) % SHARD_COUNT
```
**Invariant**: the active index root that is hashed into the shuffling seed actually is the `hash_tree_root` of the validator set that is used for that epoch.
@ -2330,7 +2217,7 @@ def process_block_header(state: BeaconState, block: BeaconBlock) -> None:
# Verify that the slots match
assert block.slot == state.slot
# Verify that the parent matches
assert block.previous_block_root == hash_tree_root(state.latest_block_header)
assert block.previous_block_root == signed_root(state.latest_block_header)
# Save current block as the new latest block
state.latest_block_header = get_temporary_block_header(block)
# Verify proposer is not slashed
@ -2473,7 +2360,8 @@ def process_attestation(state: BeaconState, attestation: Attestation) -> None:
attestation.data.previous_crosslink, # Case 1: latest crosslink matches previous crosslink
Crosslink( # Case 2: latest crosslink matches current crosslink
crosslink_data_root=attestation.data.crosslink_data_root,
epoch=target_epoch,
epoch=min(slot_to_epoch(attestation.data.slot),
attestation.data.previous_crosslink.epoch + MAX_CROSSLINK_EPOCHS)
),
}

43
specs/validator/0_beacon-chain-validator.md
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@ -331,22 +331,19 @@ signed_attestation_data = bls_sign(
## Validator assignments
A validator can get the current and previous epoch committee assignments using the following helper via `get_committee_assignment(state, epoch, validator_index)` where `previous_epoch <= epoch <= current_epoch`.
A validator can get the current, previous, and next epoch committee assignments using the following helper via `get_committee_assignment(state, epoch, validator_index)` where `previous_epoch <= epoch <= next_epoch`.
```python
def get_committee_assignment(
state: BeaconState,
epoch: Epoch,
validator_index: ValidatorIndex,
registry_change: bool=False) -> Tuple[List[ValidatorIndex], Shard, Slot, bool]:
validator_index: ValidatorIndex) -> Tuple[List[ValidatorIndex], Shard, Slot]:
"""
Return the committee assignment in the ``epoch`` for ``validator_index`` and ``registry_change``.
Return the committee assignment in the ``epoch`` for ``validator_index``.
``assignment`` returned is a tuple of the following form:
* ``assignment[0]`` is the list of validators in the committee
* ``assignment[1]`` is the shard to which the committee is assigned
* ``assignment[2]`` is the slot at which the committee is assigned
* ``assignment[3]`` is a bool signalling if the validator is expected to propose
a beacon block at the assigned slot.
"""
previous_epoch = get_previous_epoch(state)
next_epoch = get_current_epoch(state) + 1
@ -357,7 +354,6 @@ def get_committee_assignment(
crosslink_committees = get_crosslink_committees_at_slot(
state,
slot,
registry_change=registry_change,
)
selected_committees = [
committee # Tuple[List[ValidatorIndex], Shard]
@ -367,28 +363,33 @@ def get_committee_assignment(
if len(selected_committees) > 0:
validators = selected_committees[0][0]
shard = selected_committees[0][1]
is_proposer = validator_index == get_beacon_proposer_index(state, slot, registry_change=registry_change)
assignment = (validators, shard, slot, is_proposer)
assignment = (validators, shard, slot)
return assignment
```
A validator can use the following function to see if they are supposed to propose during their assigned committee slot. This function can only be run during the epoch of the slot in question and can not reliably be used to predict an epoch in advance.
```python
def is_proposer_at_slot(state: BeaconState,
slot: Slot,
validator_index: ValidatorIndex) -> bool:
current_epoch = get_current_epoch(state)
assert slot_to_epoch(slot) == current_epoch
return get_beacon_proposer_index(state, slot) == validator_index
```
_Note_: If a validator is assigned to the 0th slot of an epoch, the validator must run an empty slot transition from the previous epoch into the 0th slot of the epoch to be able to check if they are a proposer at that slot.
### Lookahead
The beacon chain shufflings are designed to provide a minimum of 1 epoch lookahead on the validator's upcoming assignments of proposing and attesting dictated by the shuffling and slot.
The beacon chain shufflings are designed to provide a minimum of 1 epoch lookahead on the validator's upcoming committee assignments for attesting dictated by the shuffling and slot. Note that this lookahead does not apply to proposing which must checked during the epoch in question.
There are three possibilities for the shuffling at the next epoch:
1. The shuffling changes due to a "validator registry change".
2. The shuffling changes due to `epochs_since_last_registry_update` being an exact power of 2 greater than 1.
3. The shuffling remains the same (i.e. the validator is in the same shard committee).
`get_committee_assignment` should be called at the start of each epoch to get the assignment for the next epoch (`current_epoch + 1`). A validator should plan for future assignments which involves noting at which future slot one will have to attest and also which shard one should begin syncing (in phase 1+).
Either (2) or (3) occurs if (1) fails. The choice between (2) and (3) is deterministic based upon `epochs_since_last_registry_update`.
When querying for assignments in the next epoch there are two options -- with and without a `registry_change` -- which is the optional fourth parameter of the `get_committee_assignment`.
`get_committee_assignment` should be called at the start of each epoch to get the assignment for the next epoch (`current_epoch + 1`). A validator should always plan for assignments from both values of `registry_change` unless the validator can concretely eliminate one of the options. Planning for future assignments involves noting at which future slot one might have to attest and propose and also which shard one should begin syncing (in phase 1+).
Specifically, a validator should call both `get_committee_assignment(state, next_epoch, validator_index, registry_change=True)` and `get_committee_assignment(state, next_epoch, validator_index, registry_change=False)` when checking for next epoch assignments.
Specifically, a validator should call `get_committee_assignment(state, next_epoch, validator_index)` when checking for next epoch assignments.
## How to avoid slashing

0
tests/phase0/__init__.py Normal file
View File

153
tests/phase0/block_processing/test_process_attestation.py Normal file
View File

@ -0,0 +1,153 @@
from copy import deepcopy
import pytest
import build.phase0.spec as spec
from build.phase0.state_transition import (
state_transition,
)
from build.phase0.spec import (
ZERO_HASH,
get_current_epoch,
process_attestation,
slot_to_epoch,
)
from tests.phase0.helpers import (
build_empty_block_for_next_slot,
get_valid_attestation,
)
# mark entire file as 'attestations'
pytestmark = pytest.mark.attestations
def run_attestation_processing(state, attestation, valid=True):
"""
Run ``process_attestation`` returning the pre and post state.
If ``valid == False``, run expecting ``AssertionError``
"""
post_state = deepcopy(state)
if not valid:
with pytest.raises(AssertionError):
process_attestation(post_state, attestation)
return state, None
process_attestation(post_state, attestation)
current_epoch = get_current_epoch(state)
target_epoch = slot_to_epoch(attestation.data.slot)
if target_epoch == current_epoch:
assert len(post_state.current_epoch_attestations) == len(state.current_epoch_attestations) + 1
else:
assert len(post_state.previous_epoch_attestations) == len(state.previous_epoch_attestations) + 1
return state, post_state
def test_success(state):
attestation = get_valid_attestation(state)
state.slot += spec.MIN_ATTESTATION_INCLUSION_DELAY
pre_state, post_state = run_attestation_processing(state, attestation)
return pre_state, attestation, post_state
def test_success_prevous_epoch(state):
attestation = get_valid_attestation(state)
block = build_empty_block_for_next_slot(state)
block.slot = state.slot + spec.SLOTS_PER_EPOCH
state_transition(state, block)
pre_state, post_state = run_attestation_processing(state, attestation)
return pre_state, attestation, post_state
def test_before_inclusion_delay(state):
attestation = get_valid_attestation(state)
# do not increment slot to allow for inclusion delay
pre_state, post_state = run_attestation_processing(state, attestation, False)
return pre_state, attestation, post_state
def test_after_epoch_slots(state):
attestation = get_valid_attestation(state)
block = build_empty_block_for_next_slot(state)
# increment past latest inclusion slot
block.slot = state.slot + spec.SLOTS_PER_EPOCH + 1
state_transition(state, block)
pre_state, post_state = run_attestation_processing(state, attestation, False)
return pre_state, attestation, post_state
def test_bad_source_epoch(state):
attestation = get_valid_attestation(state)
state.slot += spec.MIN_ATTESTATION_INCLUSION_DELAY
attestation.data.source_epoch += 10
pre_state, post_state = run_attestation_processing(state, attestation, False)
return pre_state, attestation, post_state
def test_bad_source_root(state):
attestation = get_valid_attestation(state)
state.slot += spec.MIN_ATTESTATION_INCLUSION_DELAY
attestation.data.source_root = b'\x42'*32
pre_state, post_state = run_attestation_processing(state, attestation, False)
return pre_state, attestation, post_state
def test_non_zero_crosslink_data_root(state):
attestation = get_valid_attestation(state)
state.slot += spec.MIN_ATTESTATION_INCLUSION_DELAY
attestation.data.crosslink_data_root = b'\x42'*32
pre_state, post_state = run_attestation_processing(state, attestation, False)
return pre_state, attestation, post_state
def test_bad_previous_crosslink(state):
attestation = get_valid_attestation(state)
state.slot += spec.MIN_ATTESTATION_INCLUSION_DELAY
state.latest_crosslinks[attestation.data.shard].epoch += 10
pre_state, post_state = run_attestation_processing(state, attestation, False)
return pre_state, attestation, post_state
def test_non_empty_custody_bitfield(state):
attestation = get_valid_attestation(state)
state.slot += spec.MIN_ATTESTATION_INCLUSION_DELAY
attestation.custody_bitfield = b'\x01' + attestation.custody_bitfield[1:]
pre_state, post_state = run_attestation_processing(state, attestation, False)
return pre_state, attestation, post_state
def test_empty_aggregation_bitfield(state):
attestation = get_valid_attestation(state)
state.slot += spec.MIN_ATTESTATION_INCLUSION_DELAY
attestation.aggregation_bitfield = b'\x00' * len(attestation.aggregation_bitfield)
pre_state, post_state = run_attestation_processing(state, attestation, False)
return pre_state, attestation, post_state

17
tests/phase0/block_processing/test_process_deposit.py
View File

@ -4,12 +4,14 @@ import pytest
import build.phase0.spec as spec
from build.phase0.spec import (
Deposit,
get_balance,
ZERO_HASH,
process_deposit,
)
from tests.phase0.helpers import (
build_deposit,
privkeys,
pubkeys,
)
@ -17,8 +19,10 @@ from tests.phase0.helpers import (
pytestmark = pytest.mark.voluntary_exits
def test_success(state, deposit_data_leaves, pubkeys, privkeys):
def test_success(state):
pre_state = deepcopy(state)
# fill previous deposits with zero-hash
deposit_data_leaves = [ZERO_HASH] * len(pre_state.validator_registry)
index = len(deposit_data_leaves)
pubkey = pubkeys[index]
@ -47,8 +51,9 @@ def test_success(state, deposit_data_leaves, pubkeys, privkeys):
return pre_state, deposit, post_state
def test_success_top_up(state, deposit_data_leaves, pubkeys, privkeys):
def test_success_top_up(state):
pre_state = deepcopy(state)
deposit_data_leaves = [ZERO_HASH] * len(pre_state.validator_registry)
validator_index = 0
amount = spec.MAX_DEPOSIT_AMOUNT // 4
@ -78,8 +83,9 @@ def test_success_top_up(state, deposit_data_leaves, pubkeys, privkeys):
return pre_state, deposit, post_state
def test_wrong_index(state, deposit_data_leaves, pubkeys, privkeys):
def test_wrong_index(state):
pre_state = deepcopy(state)
deposit_data_leaves = [ZERO_HASH] * len(pre_state.validator_registry)
index = len(deposit_data_leaves)
pubkey = pubkeys[index]
@ -106,8 +112,9 @@ def test_wrong_index(state, deposit_data_leaves, pubkeys, privkeys):
return pre_state, deposit, None
def test_bad_merkle_proof(state, deposit_data_leaves, pubkeys, privkeys):
def test_bad_merkle_proof(state):
pre_state = deepcopy(state)
deposit_data_leaves = [ZERO_HASH] * len(pre_state.validator_registry)
index = len(deposit_data_leaves)
pubkey = pubkeys[index]

21
tests/phase0/block_processing/test_voluntary_exit.py
View File

@ -10,6 +10,7 @@ from build.phase0.spec import (
)
from tests.phase0.helpers import (
build_voluntary_exit,
pubkey_to_privkey,
)
@ -17,7 +18,7 @@ from tests.phase0.helpers import (
pytestmark = pytest.mark.voluntary_exits
def test_success(state, pub_to_priv):
def test_success(state):
pre_state = deepcopy(state)
#
# setup pre_state
@ -30,7 +31,7 @@ def test_success(state, pub_to_priv):
#
current_epoch = get_current_epoch(pre_state)
validator_index = get_active_validator_indices(pre_state.validator_registry, current_epoch)[0]
privkey = pub_to_priv[pre_state.validator_registry[validator_index].pubkey]
privkey = pubkey_to_privkey[pre_state.validator_registry[validator_index].pubkey]
voluntary_exit = build_voluntary_exit(
pre_state,
@ -52,11 +53,11 @@ def test_success(state, pub_to_priv):
return pre_state, voluntary_exit, post_state
def test_validator_not_active(state, pub_to_priv):
def test_validator_not_active(state):
pre_state = deepcopy(state)
current_epoch = get_current_epoch(pre_state)
validator_index = get_active_validator_indices(pre_state.validator_registry, current_epoch)[0]
privkey = pub_to_priv[pre_state.validator_registry[validator_index].pubkey]
privkey = pubkey_to_privkey[pre_state.validator_registry[validator_index].pubkey]
#
# setup pre_state
@ -79,7 +80,7 @@ def test_validator_not_active(state, pub_to_priv):
return pre_state, voluntary_exit, None
def test_validator_already_exited(state, pub_to_priv):
def test_validator_already_exited(state):
pre_state = deepcopy(state)
#
# setup pre_state
@ -89,7 +90,7 @@ def test_validator_already_exited(state, pub_to_priv):
current_epoch = get_current_epoch(pre_state)
validator_index = get_active_validator_indices(pre_state.validator_registry, current_epoch)[0]
privkey = pub_to_priv[pre_state.validator_registry[validator_index].pubkey]
privkey = pubkey_to_privkey[pre_state.validator_registry[validator_index].pubkey]
# but validator already has exited
pre_state.validator_registry[validator_index].exit_epoch = current_epoch + 2
@ -110,7 +111,7 @@ def test_validator_already_exited(state, pub_to_priv):
return pre_state, voluntary_exit, None
def test_validator_already_initiated_exit(state, pub_to_priv):
def test_validator_already_initiated_exit(state):
pre_state = deepcopy(state)
#
# setup pre_state
@ -120,7 +121,7 @@ def test_validator_already_initiated_exit(state, pub_to_priv):
current_epoch = get_current_epoch(pre_state)
validator_index = get_active_validator_indices(pre_state.validator_registry, current_epoch)[0]
privkey = pub_to_priv[pre_state.validator_registry[validator_index].pubkey]
privkey = pubkey_to_privkey[pre_state.validator_registry[validator_index].pubkey]
# but validator already has initiated exit
pre_state.validator_registry[validator_index].initiated_exit = True
@ -141,14 +142,14 @@ def test_validator_already_initiated_exit(state, pub_to_priv):
return pre_state, voluntary_exit, None
def test_validator_not_active_long_enough(state, pub_to_priv):
def test_validator_not_active_long_enough(state):
pre_state = deepcopy(state)
#
# setup pre_state
#
current_epoch = get_current_epoch(pre_state)
validator_index = get_active_validator_indices(pre_state.validator_registry, current_epoch)[0]
privkey = pub_to_priv[pre_state.validator_registry[validator_index].pubkey]
privkey = pubkey_to_privkey[pre_state.validator_registry[validator_index].pubkey]
# but validator already has initiated exit
pre_state.validator_registry[validator_index].initiated_exit = True

18
tests/phase0/conftest.py
View File

@ -3,9 +3,6 @@ import pytest
from build.phase0 import spec
from tests.phase0.helpers import (
privkeys_list,
pubkeys_list,
pubkey_to_privkey,
create_genesis_state,
)
@ -25,21 +22,6 @@ MINIMAL_CONFIG = {
}
@pytest.fixture
def privkeys():
return privkeys_list
@pytest.fixture
def pubkeys():
return pubkeys_list
@pytest.fixture
def pub_to_priv():
return pubkey_to_privkey
def overwrite_spec_config(config):
for field in config:
setattr(spec, field, config[field])

89
tests/phase0/helpers.py
View File

@ -9,17 +9,20 @@ from build.phase0.spec import (
EMPTY_SIGNATURE,
ZERO_HASH,
# SSZ
Attestation,
AttestationData,
AttestationDataAndCustodyBit,
BeaconBlockHeader,
Deposit,
DepositInput,
DepositData,
Eth1Data,
ProposerSlashing,
VoluntaryExit,
# functions
get_active_validator_indices,
get_attestation_participants,
get_block_root,
get_crosslink_committees_at_slot,
get_current_epoch,
get_domain,
get_empty_block,
@ -35,27 +38,25 @@ from build.phase0.utils.merkle_minimal import (
)
privkeys_list = [i + 1 for i in range(1000)]
pubkeys_list = [bls.privtopub(privkey) for privkey in privkeys_list]
pubkey_to_privkey = {pubkey: privkey for privkey, pubkey in zip(privkeys_list, pubkeys_list)}
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):
deposit_timestamp = 0
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_list[i]
pubkey = pubkeys[i]
deposit_data = DepositData(
amount=spec.MAX_DEPOSIT_AMOUNT,
timestamp=deposit_timestamp,
deposit_input=DepositInput(
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)
@ -70,12 +71,12 @@ def create_mock_genesis_validator_deposits(num_validators, deposit_data_leaves):
genesis_validator_deposits.append(Deposit(
proof=list(get_merkle_proof(tree, item_index=i)),
index=i,
deposit_data=deposit_data_list[i]
data=deposit_data_list[i]
))
return genesis_validator_deposits, root
def create_genesis_state(num_validators, deposit_data_leaves):
def create_genesis_state(num_validators, deposit_data_leaves=None):
initial_deposits, deposit_root = create_mock_genesis_validator_deposits(
num_validators,
deposit_data_leaves,
@ -105,19 +106,20 @@ def build_empty_block_for_next_slot(state):
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 = previous_block_header.hash_tree_root()
empty_block.previous_block_root = signed_root(previous_block_header)
return empty_block
def build_deposit_data(state, pubkey, privkey, amount):
deposit_input = DepositInput(
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=signed_root(deposit_input),
message_hash=signed_root(deposit_data),
privkey=privkey,
domain=get_domain(
state.fork,
@ -125,12 +127,7 @@ def build_deposit_data(state, pubkey, privkey, amount):
spec.DOMAIN_DEPOSIT,
)
)
deposit_input.proof_of_possession = proof_of_possession
deposit_data = DepositData(
amount=amount,
timestamp=0,
deposit_input=deposit_input,
)
deposit_data.proof_of_possession = proof_of_possession
return deposit_data
@ -199,7 +196,7 @@ def build_deposit(state,
deposit = Deposit(
proof=list(proof),
index=index,
deposit_data=deposit_data,
data=deposit_data,
)
return deposit, root, deposit_data_leaves
@ -243,3 +240,49 @@ def get_valid_proposer_slashing(state):
header_1=header_1,
header_2=header_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_committees = get_crosslink_committees_at_slot(state, slot)
crosslink_committee = [committee for committee, _shard in crosslink_committees if _shard == attestation_data.shard][0]
committee_size = len(crosslink_committee)
bitfield_length = (committee_size + 7) // 8
aggregation_bitfield = b'\x01' + 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) == 1
validator_index = participants[0]
privkey = privkeys[validator_index]
message_hash = AttestationDataAndCustodyBit(
data=attestation.data,
custody_bit=0b0,
).hash_tree_root()
attestation.aggregation_signature = bls.sign(
message_hash=message_hash,
privkey=privkey,
domain=get_domain(
fork=state.fork,
epoch=get_current_epoch(state),
domain_type=spec.DOMAIN_ATTESTATION,
)
)
return attestation

68
tests/phase0/test_sanity.py
View File

@ -11,19 +11,13 @@ from build.phase0.spec import (
EMPTY_SIGNATURE,
ZERO_HASH,
# SSZ
Attestation,
AttestationDataAndCustodyBit,
BeaconBlockHeader,
Deposit,
Transfer,
ProposerSlashing,
VoluntaryExit,
# functions
get_active_validator_indices,
get_attestation_participants,
get_balance,
get_block_root,
get_crosslink_committees_at_slot,
get_current_epoch,
get_domain,
get_state_root,
@ -42,11 +36,13 @@ from build.phase0.utils.merkle_minimal import (
get_merkle_root,
)
from tests.phase0.helpers import (
build_attestation_data,
build_deposit_data,
build_empty_block_for_next_slot,
force_registry_change_at_next_epoch,
get_valid_attestation,
get_valid_proposer_slashing,
privkeys,
pubkeys,
)
@ -116,7 +112,7 @@ def test_empty_epoch_transition_not_finalizing(state):
return state, [block], test_state
def test_proposer_slashing(state, pubkeys, privkeys):
def test_proposer_slashing(state):
test_state = deepcopy(state)
proposer_slashing = get_valid_proposer_slashing(state)
validator_index = proposer_slashing.proposer_index
@ -142,9 +138,9 @@ def test_proposer_slashing(state, pubkeys, privkeys):
return state, [block], test_state
def test_deposit_in_block(state, deposit_data_leaves, pubkeys, privkeys):
def test_deposit_in_block(state):
pre_state = deepcopy(state)
test_deposit_data_leaves = deepcopy(deposit_data_leaves)
test_deposit_data_leaves = [ZERO_HASH] * len(pre_state.validator_registry)
index = len(test_deposit_data_leaves)
pubkey = pubkeys[index]
@ -161,7 +157,7 @@ def test_deposit_in_block(state, deposit_data_leaves, pubkeys, privkeys):
deposit = Deposit(
proof=list(proof),
index=index,
deposit_data=deposit_data,
data=deposit_data,
)
pre_state.latest_eth1_data.deposit_root = root
@ -179,9 +175,9 @@ def test_deposit_in_block(state, deposit_data_leaves, pubkeys, privkeys):
return pre_state, [block], post_state
def test_deposit_top_up(state, pubkeys, privkeys, deposit_data_leaves):
def test_deposit_top_up(state):
pre_state = deepcopy(state)
test_deposit_data_leaves = deepcopy(deposit_data_leaves)
test_deposit_data_leaves = [ZERO_HASH] * len(pre_state.validator_registry)
validator_index = 0
amount = spec.MAX_DEPOSIT_AMOUNT // 4
@ -200,7 +196,7 @@ def test_deposit_top_up(state, pubkeys, privkeys, deposit_data_leaves):
deposit = Deposit(
proof=list(proof),
index=merkle_index,
deposit_data=deposit_data,
data=deposit_data,
)
pre_state.latest_eth1_data.deposit_root = root
@ -218,45 +214,9 @@ def test_deposit_top_up(state, pubkeys, privkeys, deposit_data_leaves):
return pre_state, [block], post_state
def test_attestation(state, pubkeys, privkeys):
def test_attestation(state):
test_state = deepcopy(state)
slot = state.slot
shard = state.current_shuffling_start_shard
attestation_data = build_attestation_data(state, slot, shard)
crosslink_committees = get_crosslink_committees_at_slot(state, slot)
crosslink_committee = [committee for committee, _shard in crosslink_committees if _shard == attestation_data.shard][0]
# Select the first validator to be the attester
participants = [crosslink_committee[0]]
aggregation_bitfield_length = (len(crosslink_committee) + 7) // 8
custody_bitfield_length = (len(participants) + 7) // 8
aggregation_bitfield = b'\x01' + b'\x00' * (aggregation_bitfield_length - 1)
custody_bitfield = b'\x00' * custody_bitfield_length
attestation = Attestation(
aggregation_bitfield=aggregation_bitfield,
data=attestation_data,
custody_bitfield=custody_bitfield,
aggregate_signature=EMPTY_SIGNATURE,
)
validator_index = participants[0]
privkey = privkeys[validator_index]
message_hash = AttestationDataAndCustodyBit(
data=attestation.data,
custody_bit=0b0,
).hash_tree_root()
attestation.aggregation_signature = bls.sign(
message_hash=message_hash,
privkey=privkey,
domain=get_domain(
fork=test_state.fork,
epoch=get_current_epoch(test_state),
domain_type=spec.DOMAIN_ATTESTATION,
)
)
attestation = get_valid_attestation(state)
#
# Add to state via block transition
@ -283,7 +243,7 @@ def test_attestation(state, pubkeys, privkeys):
return state, [attestation_block, epoch_block], test_state
def test_voluntary_exit(state, pubkeys, privkeys):
def test_voluntary_exit(state):
pre_state = deepcopy(state)
validator_index = get_active_validator_indices(
pre_state.validator_registry,
@ -371,7 +331,7 @@ def test_no_exit_churn_too_long_since_change(state):
return pre_state, [block], post_state
def test_transfer(state, pubkeys, privkeys):
def test_transfer(state):
pre_state = deepcopy(state)
current_epoch = get_current_epoch(pre_state)
sender_index = get_active_validator_indices(pre_state.validator_registry, current_epoch)[-1]

9
utils/phase0/hash_function.py
View File

@ -1,7 +1,6 @@
# from hashlib import sha256
from eth_utils import keccak
from hashlib import sha256
# from eth_utils import keccak
# def hash(x): return sha256(x).digest()
def hash(x):
return keccak(x)
def hash(x): return sha256(x).digest()
# def hash(x): return keccak(x)

52
utils/phase0/jsonize.py Normal file
View File

@ -0,0 +1,52 @@
from .minimal_ssz import hash_tree_root
def jsonize(value, typ, include_hash_tree_roots=False):
if isinstance(typ, str) and typ[:4] == 'uint':
return value
elif typ == 'bool':
assert value in (True, False)
return value
elif isinstance(typ, list):
return [jsonize(element, typ[0], include_hash_tree_roots) for element in value]
elif isinstance(typ, str) and typ[:4] == 'byte':
return '0x' + value.hex()
elif hasattr(typ, 'fields'):
ret = {}
for field, subtype in typ.fields.items():
ret[field] = jsonize(getattr(value, field), subtype, include_hash_tree_roots)
if include_hash_tree_roots:
ret[field + "_hash_tree_root"] = '0x' + hash_tree_root(getattr(value, field), subtype).hex()
if include_hash_tree_roots:
ret["hash_tree_root"] = '0x' + hash_tree_root(value, typ).hex()
return ret
else:
print(value, typ)
raise Exception("Type not recognized")
def dejsonize(json, typ):
if isinstance(typ, str) and typ[:4] == 'uint':
return json
elif typ == 'bool':
assert json in (True, False)
return json
elif isinstance(typ, list):
return [dejsonize(element, typ[0]) for element in json]
elif isinstance(typ, str) and typ[:4] == 'byte':
return bytes.fromhex(json[2:])
elif hasattr(typ, 'fields'):
temp = {}
for field, subtype in typ.fields.items():
temp[field] = dejsonize(json[field], subtype)
if field + "_hash_tree_root" in json:
assert(json[field + "_hash_tree_root"][2:] ==
hash_tree_root(temp[field], subtype).hex())
ret = typ(**temp)
if "hash_tree_root" in json:
assert(json["hash_tree_root"][2:] ==
hash_tree_root(ret, typ).hex())
return ret
else:
print(json, typ)
raise Exception("Type not recognized")

2
utils/phase0/state_transition.py
View File

@ -95,7 +95,7 @@ def process_epoch_transition(state: BeaconState) -> None:
spec.maybe_reset_eth1_period(state)
spec.apply_rewards(state)
spec.process_ejections(state)
spec.update_registry_and_shuffling_data(state)
spec.update_registry(state)
spec.process_slashings(state)
spec.process_exit_queue(state)
spec.finish_epoch_update(state)