diff --git a/beacon_node/beacon_chain/src/attestation_aggregator.rs b/beacon_node/beacon_chain/src/attestation_aggregator.rs deleted file mode 100644 index 9b4e5a687..000000000 --- a/beacon_node/beacon_chain/src/attestation_aggregator.rs +++ /dev/null @@ -1,218 +0,0 @@ -use ssz::TreeHash; -use state_processing::per_block_processing::validate_attestation_without_signature; -use std::collections::{HashMap, HashSet}; -use types::*; - -const PHASE_0_CUSTODY_BIT: bool = false; - -/// Provides the functionality to: -/// -/// - Recieve a `FreeAttestation` and aggregate it into an `Attestation` (or create a new if it -/// doesn't exist). -/// - Store all aggregated or created `Attestation`s. -/// - Produce a list of attestations that would be valid for inclusion in some `BeaconState` (and -/// therefore valid for inclusion in a `BeaconBlock`. -/// -/// Note: `Attestations` are stored in memory and never deleted. This is not scalable and must be -/// rectified in a future revision. -#[derive(Default)] -pub struct AttestationAggregator { - store: HashMap, Attestation>, -} - -pub struct Outcome { - pub valid: bool, - pub message: Message, -} - -pub enum Message { - /// The free attestation was added to an existing attestation. - Aggregated, - /// The free attestation has already been aggregated to an existing attestation. - AggregationNotRequired, - /// The free attestation was transformed into a new attestation. - NewAttestationCreated, - /// The supplied `validator_index` is not in the committee for the given `shard` and `slot`. - BadValidatorIndex, - /// The given `signature` did not match the `pubkey` in the given - /// `state.validator_registry`. - BadSignature, - /// The given `slot` does not match the validators committee assignment. - BadSlot, - /// The given `shard` does not match the validators committee assignment, or is not included in - /// a committee for the given slot. - BadShard, - /// Attestation is from the epoch prior to this, ignoring. - TooOld, -} - -macro_rules! valid_outcome { - ($error: expr) => { - return Ok(Outcome { - valid: true, - message: $error, - }); - }; -} - -macro_rules! invalid_outcome { - ($error: expr) => { - return Ok(Outcome { - valid: false, - message: $error, - }); - }; -} - -impl AttestationAggregator { - /// Instantiates a new AttestationAggregator with an empty database. - pub fn new() -> Self { - Self { - store: HashMap::new(), - } - } - - /// Accepts some `FreeAttestation`, validates it and either aggregates it upon some existing - /// `Attestation` or produces a new `Attestation`. - /// - /// The "validation" provided is not complete, instead the following points are checked: - /// - The given `validator_index` is in the committee for the given `shard` for the given - /// `slot`. - /// - The signature is verified against that of the validator at `validator_index`. - pub fn process_free_attestation( - &mut self, - state: &BeaconState, - free_attestation: &FreeAttestation, - spec: &ChainSpec, - ) -> Result { - let duties = - match state.get_attestation_duties(free_attestation.validator_index as usize, spec) { - Err(BeaconStateError::EpochCacheUninitialized(e)) => { - panic!("Attempted to access unbuilt cache {:?}.", e) - } - Err(BeaconStateError::EpochOutOfBounds) => invalid_outcome!(Message::TooOld), - Err(BeaconStateError::ShardOutOfBounds) => invalid_outcome!(Message::BadShard), - Err(e) => return Err(e), - Ok(None) => invalid_outcome!(Message::BadValidatorIndex), - Ok(Some(attestation_duties)) => attestation_duties, - }; - - if free_attestation.data.slot != duties.slot { - invalid_outcome!(Message::BadSlot); - } - if free_attestation.data.shard != duties.shard { - invalid_outcome!(Message::BadShard); - } - - let signable_message = AttestationDataAndCustodyBit { - data: free_attestation.data.clone(), - custody_bit: PHASE_0_CUSTODY_BIT, - } - .hash_tree_root(); - - let validator_record = match state - .validator_registry - .get(free_attestation.validator_index as usize) - { - None => invalid_outcome!(Message::BadValidatorIndex), - Some(validator_record) => validator_record, - }; - - if !free_attestation.signature.verify( - &signable_message, - spec.get_domain(state.current_epoch(spec), Domain::Attestation, &state.fork), - &validator_record.pubkey, - ) { - invalid_outcome!(Message::BadSignature); - } - - if let Some(existing_attestation) = self.store.get(&signable_message) { - if let Some(updated_attestation) = aggregate_attestation( - existing_attestation, - &free_attestation.signature, - duties.committee_index as usize, - ) { - self.store.insert(signable_message, updated_attestation); - valid_outcome!(Message::Aggregated); - } else { - valid_outcome!(Message::AggregationNotRequired); - } - } else { - let mut aggregate_signature = AggregateSignature::new(); - aggregate_signature.add(&free_attestation.signature); - let mut aggregation_bitfield = Bitfield::new(); - aggregation_bitfield.set(duties.committee_index as usize, true); - let new_attestation = Attestation { - data: free_attestation.data.clone(), - aggregation_bitfield, - custody_bitfield: Bitfield::new(), - aggregate_signature, - }; - self.store.insert(signable_message, new_attestation); - valid_outcome!(Message::NewAttestationCreated); - } - } - - /// Returns all known attestations which are: - /// - /// - Valid for the given state - /// - Not already in `state.latest_attestations`. - pub fn get_attestations_for_state( - &self, - state: &BeaconState, - spec: &ChainSpec, - ) -> Vec { - let mut known_attestation_data: HashSet = HashSet::new(); - - state - .previous_epoch_attestations - .iter() - .chain(state.current_epoch_attestations.iter()) - .for_each(|attestation| { - known_attestation_data.insert(attestation.data.clone()); - }); - - self.store - .values() - .filter_map(|attestation| { - if validate_attestation_without_signature(&state, attestation, spec).is_ok() - && !known_attestation_data.contains(&attestation.data) - { - Some(attestation.clone()) - } else { - None - } - }) - .collect() - } -} - -/// Produces a new `Attestation` where: -/// -/// - `signature` is added to `Attestation.aggregate_signature` -/// - Attestation.aggregation_bitfield[committee_index]` is set to true. -fn aggregate_attestation( - existing_attestation: &Attestation, - signature: &Signature, - committee_index: usize, -) -> Option { - let already_signed = existing_attestation - .aggregation_bitfield - .get(committee_index) - .unwrap_or(false); - - if already_signed { - None - } else { - let mut aggregation_bitfield = existing_attestation.aggregation_bitfield.clone(); - aggregation_bitfield.set(committee_index, true); - let mut aggregate_signature = existing_attestation.aggregate_signature.clone(); - aggregate_signature.add(&signature); - - Some(Attestation { - aggregation_bitfield, - aggregate_signature, - ..existing_attestation.clone() - }) - } -} diff --git a/beacon_node/beacon_chain/src/lib.rs b/beacon_node/beacon_chain/src/lib.rs index 409b86e02..8b8fcb5e6 100644 --- a/beacon_node/beacon_chain/src/lib.rs +++ b/beacon_node/beacon_chain/src/lib.rs @@ -1,4 +1,3 @@ -mod attestation_aggregator; mod beacon_chain; mod checkpoint; mod errors; @@ -8,7 +7,6 @@ pub mod test_utils; pub use self::beacon_chain::{BeaconChain, BlockProcessingOutcome, InvalidBlock, ValidBlock}; pub use self::checkpoint::CheckPoint; pub use self::errors::BeaconChainError; -pub use attestation_aggregator::Outcome as AggregationOutcome; pub use db; pub use fork_choice; pub use parking_lot;