lighthouse/beacon_node/beacon_chain/tests/tests.rs
Paul Hauner be11437c27 Batch BLS verification for attestations (#2399)
## Issue Addressed

NA

## Proposed Changes

Adds the ability to verify batches of aggregated/unaggregated attestations from the network.

When the `BeaconProcessor` finds there are messages in the aggregated or unaggregated attestation queues, it will first check the length of the queue:

- `== 1` verify the attestation individually.
- `>= 2` take up to 64 of those attestations and verify them in a batch.

Notably, we only perform batch verification if the queue has a backlog. We don't apply any artificial delays to attestations to try and force them into batches. 

### Batching Details

To assist with implementing batches we modify `beacon_chain::attestation_verification` to have two distinct categories for attestations:

- *Indexed* attestations: those which have passed initial validation and were valid enough for us to derive an `IndexedAttestation`.
- *Verified* attestations: those attestations which were indexed *and also* passed signature verification. These are well-formed, interesting messages which were signed by validators.

The batching functions accept `n` attestations and then return `n` attestation verification `Result`s, where those `Result`s can be any combination of `Ok` or `Err`. In other words, we attempt to verify as many attestations as possible and return specific per-attestation results so peer scores can be updated, if required.

When we batch verify attestations, we first try to map all those attestations to *indexed* attestations. If any of those attestations were able to be indexed, we then perform batch BLS verification on those indexed attestations. If the batch verification succeeds, we convert them into *verified* attestations, disabling individual signature checking. If the batch fails, we convert to verified attestations with individual signature checking enabled.

Ultimately, we optimistically try to do a batch verification of attestation signatures and fall-back to individual verification if it fails. This opens an attach vector for "poisoning" the attestations and causing us to waste a batch verification. I argue that peer scoring should do a good-enough job of defending against this and the typical-case gains massively outweigh the worst-case losses.

## Additional Info

Before this PR, attestation verification took the attestations by value (instead of by reference). It turns out that this was unnecessary and, in my opinion, resulted in some undesirable ergonomics (e.g., we had to pass the attestation back in the `Err` variant to avoid clones). In this PR I've modified attestation verification so that it now takes a reference.

I refactored the `beacon_chain/tests/attestation_verification.rs` tests so they use a builder-esque "tester" struct instead of a weird macro. It made it easier for me to test individual/batch with the same set of tests and I think it was a nice tidy-up. Notably, I did this last to try and make sure my new refactors to *actual* production code would pass under the existing test suite.
2021-09-22 08:49:41 +00:00

839 lines
24 KiB
Rust

#![cfg(not(debug_assertions))]
#[macro_use]
extern crate lazy_static;
use beacon_chain::{
attestation_verification::Error as AttnError,
test_utils::{
AttestationStrategy, BeaconChainHarness, BlockStrategy, EphemeralHarnessType,
OP_POOL_DB_KEY,
},
StateSkipConfig, WhenSlotSkipped,
};
use operation_pool::PersistedOperationPool;
use state_processing::{
per_slot_processing, per_slot_processing::Error as SlotProcessingError, EpochProcessingError,
};
use store::config::StoreConfig;
use types::{BeaconStateError, EthSpec, Hash256, Keypair, MinimalEthSpec, RelativeEpoch, Slot};
// Should ideally be divisible by 3.
pub const VALIDATOR_COUNT: usize = 24;
lazy_static! {
/// A cached set of keys.
static ref KEYPAIRS: Vec<Keypair> = types::test_utils::generate_deterministic_keypairs(VALIDATOR_COUNT);
}
fn get_harness(validator_count: usize) -> BeaconChainHarness<EphemeralHarnessType<MinimalEthSpec>> {
let harness = BeaconChainHarness::new_with_store_config(
MinimalEthSpec,
None,
KEYPAIRS[0..validator_count].to_vec(),
StoreConfig::default(),
);
harness.advance_slot();
harness
}
#[test]
fn massive_skips() {
let harness = get_harness(8);
let spec = &harness.chain.spec;
let mut state = harness.chain.head().expect("should get head").beacon_state;
// Run per_slot_processing until it returns an error.
let error = loop {
match per_slot_processing(&mut state, None, spec) {
Ok(_) => continue,
Err(e) => break e,
}
};
assert!(state.slot() > 1, "the state should skip at least one slot");
assert_eq!(
error,
SlotProcessingError::EpochProcessingError(EpochProcessingError::BeaconStateError(
BeaconStateError::InsufficientValidators
)),
"should return error indicating that validators have been slashed out"
)
}
#[test]
fn iterators() {
let num_blocks_produced = MinimalEthSpec::slots_per_epoch() * 2 - 1;
let harness = get_harness(VALIDATOR_COUNT);
harness.extend_chain(
num_blocks_produced as usize,
BlockStrategy::OnCanonicalHead,
// No need to produce attestations for this test.
AttestationStrategy::SomeValidators(vec![]),
);
let block_roots: Vec<(Hash256, Slot)> = harness
.chain
.forwards_iter_block_roots(Slot::new(0))
.expect("should get iter")
.map(Result::unwrap)
.collect();
let state_roots: Vec<(Hash256, Slot)> = harness
.chain
.forwards_iter_state_roots(Slot::new(0))
.expect("should get iter")
.map(Result::unwrap)
.collect();
assert_eq!(
block_roots.len(),
state_roots.len(),
"should be an equal amount of block and state roots"
);
assert!(
block_roots.iter().any(|(_root, slot)| *slot == 0),
"should contain genesis block root"
);
assert!(
state_roots.iter().any(|(_root, slot)| *slot == 0),
"should contain genesis state root"
);
assert_eq!(
block_roots.len(),
num_blocks_produced as usize + 1,
"should contain all produced blocks, plus the genesis block"
);
block_roots.windows(2).for_each(|x| {
assert_eq!(
x[1].1,
x[0].1 + 1,
"block root slots should be increasing by one"
)
});
state_roots.windows(2).for_each(|x| {
assert_eq!(
x[1].1,
x[0].1 + 1,
"state root slots should be increasing by one"
)
});
let head = &harness.chain.head().expect("should get head");
assert_eq!(
*block_roots.last().expect("should have some block roots"),
(head.beacon_block_root, head.beacon_block.slot()),
"last block root and slot should be for the head block"
);
assert_eq!(
*state_roots.last().expect("should have some state roots"),
(head.beacon_state_root(), head.beacon_state.slot()),
"last state root and slot should be for the head state"
);
}
#[test]
fn find_reorgs() {
let num_blocks_produced = MinimalEthSpec::slots_per_historical_root() + 1;
let harness = get_harness(VALIDATOR_COUNT);
harness.extend_chain(
num_blocks_produced as usize,
BlockStrategy::OnCanonicalHead,
// No need to produce attestations for this test.
AttestationStrategy::SomeValidators(vec![]),
);
let head_state = harness.chain.head_beacon_state().unwrap();
let head_slot = head_state.slot();
let genesis_state = harness
.chain
.state_at_slot(Slot::new(0), StateSkipConfig::WithStateRoots)
.unwrap();
// because genesis is more than `SLOTS_PER_HISTORICAL_ROOT` away, this should return with the
// finalized slot.
assert_eq!(
harness
.chain
.find_reorg_slot(&genesis_state, harness.chain.genesis_block_root)
.unwrap(),
head_state
.finalized_checkpoint()
.epoch
.start_slot(MinimalEthSpec::slots_per_epoch())
);
// test head
assert_eq!(
harness
.chain
.find_reorg_slot(
&head_state,
harness.chain.head_beacon_block().unwrap().canonical_root()
)
.unwrap(),
head_slot
);
// Re-org back to the slot prior to the head.
let prev_slot = head_slot - Slot::new(1);
let prev_state = harness
.chain
.state_at_slot(prev_slot, StateSkipConfig::WithStateRoots)
.unwrap();
let prev_block_root = harness
.chain
.block_root_at_slot(prev_slot, WhenSlotSkipped::None)
.unwrap()
.unwrap();
assert_eq!(
harness
.chain
.find_reorg_slot(&prev_state, prev_block_root)
.unwrap(),
prev_slot
);
}
#[test]
fn chooses_fork() {
let harness = get_harness(VALIDATOR_COUNT);
let two_thirds = (VALIDATOR_COUNT / 3) * 2;
let delay = MinimalEthSpec::default_spec().min_attestation_inclusion_delay as usize;
let honest_validators: Vec<usize> = (0..two_thirds).collect();
let faulty_validators: Vec<usize> = (two_thirds..VALIDATOR_COUNT).collect();
let initial_blocks = delay + 1;
let honest_fork_blocks = delay + 1;
let faulty_fork_blocks = delay + 2;
// Build an initial chain where all validators agree.
harness.extend_chain(
initial_blocks,
BlockStrategy::OnCanonicalHead,
AttestationStrategy::AllValidators,
);
let (honest_head, faulty_head) = harness.generate_two_forks_by_skipping_a_block(
&honest_validators,
&faulty_validators,
honest_fork_blocks,
faulty_fork_blocks,
);
assert_ne!(honest_head, faulty_head, "forks should be distinct");
let state = &harness.chain.head().expect("should get head").beacon_state;
assert_eq!(
state.slot(),
Slot::from(initial_blocks + honest_fork_blocks),
"head should be at the current slot"
);
assert_eq!(
harness
.chain
.head()
.expect("should get head")
.beacon_block_root,
honest_head,
"the honest chain should be the canonical chain"
);
}
#[test]
fn finalizes_with_full_participation() {
let num_blocks_produced = MinimalEthSpec::slots_per_epoch() * 5;
let harness = get_harness(VALIDATOR_COUNT);
harness.extend_chain(
num_blocks_produced as usize,
BlockStrategy::OnCanonicalHead,
AttestationStrategy::AllValidators,
);
let state = &harness.chain.head().expect("should get head").beacon_state;
assert_eq!(
state.slot(),
num_blocks_produced,
"head should be at the current slot"
);
assert_eq!(
state.current_epoch(),
num_blocks_produced / MinimalEthSpec::slots_per_epoch(),
"head should be at the expected epoch"
);
assert_eq!(
state.current_justified_checkpoint().epoch,
state.current_epoch() - 1,
"the head should be justified one behind the current epoch"
);
assert_eq!(
state.finalized_checkpoint().epoch,
state.current_epoch() - 2,
"the head should be finalized two behind the current epoch"
);
}
#[test]
fn finalizes_with_two_thirds_participation() {
let num_blocks_produced = MinimalEthSpec::slots_per_epoch() * 5;
let harness = get_harness(VALIDATOR_COUNT);
let two_thirds = (VALIDATOR_COUNT / 3) * 2;
let attesters = (0..two_thirds).collect();
harness.extend_chain(
num_blocks_produced as usize,
BlockStrategy::OnCanonicalHead,
AttestationStrategy::SomeValidators(attesters),
);
let state = &harness.chain.head().expect("should get head").beacon_state;
assert_eq!(
state.slot(),
num_blocks_produced,
"head should be at the current slot"
);
assert_eq!(
state.current_epoch(),
num_blocks_produced / MinimalEthSpec::slots_per_epoch(),
"head should be at the expected epoch"
);
// Note: the 2/3rds tests are not justifying the immediately prior epochs because the
// `MIN_ATTESTATION_INCLUSION_DELAY` is preventing an adequate number of attestations being
// included in blocks during that epoch.
assert_eq!(
state.current_justified_checkpoint().epoch,
state.current_epoch() - 2,
"the head should be justified two behind the current epoch"
);
assert_eq!(
state.finalized_checkpoint().epoch,
state.current_epoch() - 4,
"the head should be finalized three behind the current epoch"
);
}
#[test]
fn does_not_finalize_with_less_than_two_thirds_participation() {
let num_blocks_produced = MinimalEthSpec::slots_per_epoch() * 5;
let harness = get_harness(VALIDATOR_COUNT);
let two_thirds = (VALIDATOR_COUNT / 3) * 2;
let less_than_two_thirds = two_thirds - 1;
let attesters = (0..less_than_two_thirds).collect();
harness.extend_chain(
num_blocks_produced as usize,
BlockStrategy::OnCanonicalHead,
AttestationStrategy::SomeValidators(attesters),
);
let state = &harness.chain.head().expect("should get head").beacon_state;
assert_eq!(
state.slot(),
num_blocks_produced,
"head should be at the current slot"
);
assert_eq!(
state.current_epoch(),
num_blocks_produced / MinimalEthSpec::slots_per_epoch(),
"head should be at the expected epoch"
);
assert_eq!(
state.current_justified_checkpoint().epoch,
0,
"no epoch should have been justified"
);
assert_eq!(
state.finalized_checkpoint().epoch,
0,
"no epoch should have been finalized"
);
}
#[test]
fn does_not_finalize_without_attestation() {
let num_blocks_produced = MinimalEthSpec::slots_per_epoch() * 5;
let harness = get_harness(VALIDATOR_COUNT);
harness.extend_chain(
num_blocks_produced as usize,
BlockStrategy::OnCanonicalHead,
AttestationStrategy::SomeValidators(vec![]),
);
let state = &harness.chain.head().expect("should get head").beacon_state;
assert_eq!(
state.slot(),
num_blocks_produced,
"head should be at the current slot"
);
assert_eq!(
state.current_epoch(),
num_blocks_produced / MinimalEthSpec::slots_per_epoch(),
"head should be at the expected epoch"
);
assert_eq!(
state.current_justified_checkpoint().epoch,
0,
"no epoch should have been justified"
);
assert_eq!(
state.finalized_checkpoint().epoch,
0,
"no epoch should have been finalized"
);
}
#[test]
fn roundtrip_operation_pool() {
let num_blocks_produced = MinimalEthSpec::slots_per_epoch() * 5;
let harness = get_harness(VALIDATOR_COUNT);
// Add some attestations
harness.extend_chain(
num_blocks_produced as usize,
BlockStrategy::OnCanonicalHead,
AttestationStrategy::AllValidators,
);
assert!(harness.chain.op_pool.num_attestations() > 0);
// TODO: could add some other operations
harness
.chain
.persist_op_pool()
.expect("should persist op pool");
let restored_op_pool = harness
.chain
.store
.get_item::<PersistedOperationPool<MinimalEthSpec>>(&OP_POOL_DB_KEY)
.expect("should read db")
.expect("should find op pool")
.into_operation_pool()
.unwrap();
assert_eq!(harness.chain.op_pool, restored_op_pool);
}
#[test]
fn unaggregated_attestations_added_to_fork_choice_some_none() {
let num_blocks_produced = MinimalEthSpec::slots_per_epoch() / 2;
let harness = get_harness(VALIDATOR_COUNT);
harness.extend_chain(
num_blocks_produced as usize,
BlockStrategy::OnCanonicalHead,
AttestationStrategy::AllValidators,
);
let state = &harness.chain.head().expect("should get head").beacon_state;
let mut fork_choice = harness.chain.fork_choice.write();
// Move forward a slot so all queued attestations can be processed.
harness.advance_slot();
fork_choice
.update_time(harness.chain.slot().unwrap())
.unwrap();
let validator_slots: Vec<(usize, Slot)> = (0..VALIDATOR_COUNT)
.into_iter()
.map(|validator_index| {
let slot = state
.get_attestation_duties(validator_index, RelativeEpoch::Current)
.expect("should get attester duties")
.unwrap()
.slot;
(validator_index, slot)
})
.collect();
for (validator, slot) in validator_slots.clone() {
let latest_message = fork_choice.latest_message(validator);
if slot <= num_blocks_produced && slot != 0 {
assert_eq!(
latest_message.unwrap().1,
slot.epoch(MinimalEthSpec::slots_per_epoch()),
"Latest message epoch for {} should be equal to epoch {}.",
validator,
slot
)
} else {
assert!(
latest_message.is_none(),
"Latest message slot should be None."
)
}
}
}
#[test]
fn attestations_with_increasing_slots() {
let num_blocks_produced = MinimalEthSpec::slots_per_epoch() * 5;
let harness = get_harness(VALIDATOR_COUNT);
let mut attestations = vec![];
for _ in 0..num_blocks_produced {
harness.extend_chain(
2,
BlockStrategy::OnCanonicalHead,
// Don't produce & include any attestations (we'll collect them later).
AttestationStrategy::SomeValidators(vec![]),
);
let head = harness.chain.head().unwrap();
let head_state_root = head.beacon_state_root();
attestations.extend(harness.get_unaggregated_attestations(
&AttestationStrategy::AllValidators,
&head.beacon_state,
head_state_root,
head.beacon_block_root,
head.beacon_block.slot(),
));
harness.advance_slot();
}
for (attestation, subnet_id) in attestations.into_iter().flatten() {
let res = harness
.chain
.verify_unaggregated_attestation_for_gossip(&attestation, Some(subnet_id));
let current_slot = harness.chain.slot().expect("should get slot");
let expected_attestation_slot = attestation.data.slot;
let expected_earliest_permissible_slot =
current_slot - MinimalEthSpec::slots_per_epoch() - 1;
if expected_attestation_slot < expected_earliest_permissible_slot {
assert!(matches!(
res.err().unwrap(),
AttnError::PastSlot {
attestation_slot,
earliest_permissible_slot,
}
if attestation_slot == expected_attestation_slot && earliest_permissible_slot == expected_earliest_permissible_slot
))
} else {
res.expect("should process attestation");
}
}
}
#[test]
fn unaggregated_attestations_added_to_fork_choice_all_updated() {
let num_blocks_produced = MinimalEthSpec::slots_per_epoch() * 2 - 1;
let harness = get_harness(VALIDATOR_COUNT);
harness.extend_chain(
num_blocks_produced as usize,
BlockStrategy::OnCanonicalHead,
AttestationStrategy::AllValidators,
);
let state = &harness.chain.head().expect("should get head").beacon_state;
let mut fork_choice = harness.chain.fork_choice.write();
// Move forward a slot so all queued attestations can be processed.
harness.advance_slot();
fork_choice
.update_time(harness.chain.slot().unwrap())
.unwrap();
let validators: Vec<usize> = (0..VALIDATOR_COUNT).collect();
let slots: Vec<Slot> = validators
.iter()
.map(|&v| {
state
.get_attestation_duties(v, RelativeEpoch::Current)
.expect("should get attester duties")
.unwrap()
.slot
})
.collect();
let validator_slots: Vec<(&usize, Slot)> = validators.iter().zip(slots).collect();
for (validator, slot) in validator_slots {
let latest_message = fork_choice.latest_message(*validator);
assert_eq!(
latest_message.unwrap().1,
slot.epoch(MinimalEthSpec::slots_per_epoch()),
"Latest message slot should be equal to attester duty."
);
if slot != num_blocks_produced {
let block_root = state
.get_block_root(slot)
.expect("Should get block root at slot");
assert_eq!(
latest_message.unwrap().0,
*block_root,
"Latest message block root should be equal to block at slot."
);
}
}
}
fn run_skip_slot_test(skip_slots: u64) {
let num_validators = 8;
let harness_a = get_harness(num_validators);
let harness_b = get_harness(num_validators);
for _ in 0..skip_slots {
harness_a.advance_slot();
harness_b.advance_slot();
}
harness_a.extend_chain(
1,
BlockStrategy::OnCanonicalHead,
// No attestation required for test.
AttestationStrategy::SomeValidators(vec![]),
);
assert_eq!(
harness_a
.chain
.head()
.expect("should get head")
.beacon_block
.slot(),
Slot::new(skip_slots + 1)
);
assert_eq!(
harness_b
.chain
.head()
.expect("should get head")
.beacon_block
.slot(),
Slot::new(0)
);
assert_eq!(
harness_b
.chain
.process_block(
harness_a
.chain
.head()
.expect("should get head")
.beacon_block
.clone(),
)
.unwrap(),
harness_a
.chain
.head()
.expect("should get head")
.beacon_block_root
);
harness_b
.chain
.fork_choice()
.expect("should run fork choice");
assert_eq!(
harness_b
.chain
.head()
.expect("should get head")
.beacon_block
.slot(),
Slot::new(skip_slots + 1)
);
}
#[test]
fn produces_and_processes_with_genesis_skip_slots() {
for i in 0..MinimalEthSpec::slots_per_epoch() * 4 {
run_skip_slot_test(i)
}
}
#[test]
fn block_roots_skip_slot_behaviour() {
let harness = get_harness(VALIDATOR_COUNT);
// Test should be longer than the block roots to ensure a DB lookup is triggered.
let chain_length = harness
.chain
.head()
.unwrap()
.beacon_state
.block_roots()
.len() as u64
* 3;
let skipped_slots = [1, 6, 7, 10, chain_length];
// Build a chain with some skip slots.
for i in 1..=chain_length {
if i > 1 {
harness.advance_slot();
}
let slot = harness.chain.slot().unwrap().as_u64();
if !skipped_slots.contains(&slot) {
harness.extend_chain(
1,
BlockStrategy::OnCanonicalHead,
AttestationStrategy::AllValidators,
);
}
}
let mut prev_unskipped_root = None;
for target_slot in 0..=chain_length {
if skipped_slots.contains(&target_slot) {
/*
* A skip slot
*/
assert!(
harness
.chain
.block_root_at_slot(target_slot.into(), WhenSlotSkipped::None)
.unwrap()
.is_none(),
"WhenSlotSkipped::None should return None on a skip slot"
);
let skipped_root = harness
.chain
.block_root_at_slot(target_slot.into(), WhenSlotSkipped::Prev)
.unwrap()
.expect("WhenSlotSkipped::Prev should always return Some");
assert_eq!(
skipped_root,
prev_unskipped_root.expect("test is badly formed"),
"WhenSlotSkipped::Prev should accurately return the prior skipped block"
);
let expected_block = harness.chain.get_block(&skipped_root).unwrap().unwrap();
assert_eq!(
harness
.chain
.block_at_slot(target_slot.into(), WhenSlotSkipped::Prev)
.unwrap()
.unwrap(),
expected_block,
);
assert!(
harness
.chain
.block_at_slot(target_slot.into(), WhenSlotSkipped::None)
.unwrap()
.is_none(),
"WhenSlotSkipped::None should return None on a skip slot"
);
} else {
/*
* Not a skip slot
*/
let skips_none = harness
.chain
.block_root_at_slot(target_slot.into(), WhenSlotSkipped::None)
.unwrap()
.expect("WhenSlotSkipped::None should return Some for non-skipped block");
let skips_prev = harness
.chain
.block_root_at_slot(target_slot.into(), WhenSlotSkipped::Prev)
.unwrap()
.expect("WhenSlotSkipped::Prev should always return Some");
assert_eq!(
skips_none, skips_prev,
"WhenSlotSkipped::None and WhenSlotSkipped::Prev should be equal on non-skipped slot"
);
let expected_block = harness.chain.get_block(&skips_prev).unwrap().unwrap();
assert_eq!(
harness
.chain
.block_at_slot(target_slot.into(), WhenSlotSkipped::Prev)
.unwrap()
.unwrap(),
expected_block
);
assert_eq!(
harness
.chain
.block_at_slot(target_slot.into(), WhenSlotSkipped::None)
.unwrap()
.unwrap(),
expected_block
);
prev_unskipped_root = Some(skips_prev);
}
}
/*
* A future, non-existent slot.
*/
let future_slot = harness.chain.slot().unwrap() + 1;
assert_eq!(
harness.chain.head().unwrap().beacon_block.slot(),
future_slot - 2,
"test precondition"
);
assert!(
harness
.chain
.block_root_at_slot(future_slot, WhenSlotSkipped::None)
.unwrap()
.is_none(),
"WhenSlotSkipped::None should return None on a future slot"
);
assert!(
harness
.chain
.block_root_at_slot(future_slot, WhenSlotSkipped::Prev)
.unwrap()
.is_none(),
"WhenSlotSkipped::Prev should return None on a future slot"
);
}