mirror of
https://github.com/sigp/lighthouse.git
synced 2026-03-15 02:42:38 +00:00
Update fork choice for v0.9.1
This commit is contained in:
@@ -326,6 +326,44 @@ impl<T: BeaconChainTypes> BeaconChain<T> {
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ReverseBlockRootIterator::new((head.beacon_block_root, head.beacon_block.slot), iter)
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}
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/// Traverse backwards from `block_root` to find the block roots of its ancestors.
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///
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/// ## Notes
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///
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/// `slot` always decreases by `1`.
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/// - Skipped slots contain the root of the closest prior
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/// non-skipped slot (identical to the way they are stored in `state.block_roots`) .
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/// - Iterator returns `(Hash256, Slot)`.
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/// - The provided `block_root` is included as the first item in the iterator.
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pub fn rev_iter_block_roots_from(
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&self,
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block_root: Hash256,
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) -> Result<ReverseBlockRootIterator<T::EthSpec, T::Store>, Error> {
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let block = self
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.get_block(&block_root)?
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.ok_or_else(|| Error::MissingBeaconBlock(block_root))?;
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let state = self
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.get_state(&block.state_root)?
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.ok_or_else(|| Error::MissingBeaconState(block.state_root))?;
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let iter = BlockRootsIterator::owned(self.store.clone(), state);
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Ok(ReverseBlockRootIterator::new(
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(block_root, block.slot),
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iter,
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))
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}
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/// Traverse backwards from `block_root` to find the root of the ancestor block at `slot`.
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pub fn get_ancestor_block_root(
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&self,
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block_root: Hash256,
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slot: Slot,
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) -> Result<Option<Hash256>, Error> {
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Ok(self
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.rev_iter_block_roots_from(block_root)?
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.find(|(_, ancestor_slot)| *ancestor_slot == slot)
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.map(|(ancestor_block_root, _)| ancestor_block_root))
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}
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/// Iterates across all `(state_root, slot)` pairs from the head of the chain (inclusive) to
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/// the earliest reachable ancestor (may or may not be genesis).
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///
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@@ -356,6 +394,18 @@ impl<T: BeaconChainTypes> BeaconChain<T> {
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Ok(self.store.get(block_root)?)
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}
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/// Returns the state at the given root, if any.
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///
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/// ## Errors
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///
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/// May return a database error.
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pub fn get_state(
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&self,
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state_root: &Hash256,
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) -> Result<Option<BeaconState<T::EthSpec>>, Error> {
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Ok(self.store.get(state_root)?)
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}
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/// Returns a `Checkpoint` representing the head block and state. Contains the "best block";
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/// the head of the canonical `BeaconChain`.
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///
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@@ -871,20 +921,27 @@ impl<T: BeaconChainTypes> BeaconChain<T> {
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Ok(AttestationProcessingOutcome::Invalid(e))
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} else {
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// Provide the attestation to fork choice, updating the validator latest messages but
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// _without_ finding and updating the head.
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if let Err(e) = self
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.fork_choice
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.process_attestation(&state, &attestation, block)
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// If the attestation is from the current or previous epoch, supply it to the fork
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// choice. This is FMD GHOST.
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let current_epoch = self.epoch()?;
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if attestation.data.target.epoch == current_epoch
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|| attestation.data.target.epoch == current_epoch - 1
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{
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error!(
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self.log,
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"Add attestation to fork choice failed";
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"fork_choice_integrity" => format!("{:?}", self.fork_choice.verify_integrity()),
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"beacon_block_root" => format!("{}", attestation.data.beacon_block_root),
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"error" => format!("{:?}", e)
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);
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return Err(e.into());
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// Provide the attestation to fork choice, updating the validator latest messages but
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// _without_ finding and updating the head.
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if let Err(e) = self
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.fork_choice
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.process_attestation(&state, &attestation, block)
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{
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error!(
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self.log,
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"Add attestation to fork choice failed";
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"fork_choice_integrity" => format!("{:?}", self.fork_choice.verify_integrity()),
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"beacon_block_root" => format!("{}", attestation.data.beacon_block_root),
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"error" => format!("{:?}", e)
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);
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return Err(e.into());
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}
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}
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// Provide the valid attestation to op pool, which may choose to retain the
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@@ -1194,7 +1251,10 @@ impl<T: BeaconChainTypes> BeaconChain<T> {
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metrics::start_timer(&metrics::BLOCK_PROCESSING_FORK_CHOICE_REGISTER);
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// Register the new block with the fork choice service.
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if let Err(e) = self.fork_choice.process_block(&state, &block, block_root) {
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if let Err(e) = self
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.fork_choice
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.process_block(self, &state, &block, block_root)
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{
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error!(
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self.log,
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"Add block to fork choice failed";
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@@ -18,7 +18,6 @@ macro_rules! easy_from_to {
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#[derive(Debug, PartialEq)]
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pub enum BeaconChainError {
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InsufficientValidators,
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BadRecentBlockRoots,
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UnableToReadSlot,
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RevertedFinalizedEpoch {
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previous_epoch: Epoch,
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@@ -1,10 +1,11 @@
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use crate::{metrics, BeaconChain, BeaconChainTypes};
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use crate::{errors::BeaconChainError, metrics, BeaconChain, BeaconChainTypes};
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use lmd_ghost::LmdGhost;
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use state_processing::common::get_attesting_indices;
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use parking_lot::RwLock;
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use state_processing::{common::get_attesting_indices, per_slot_processing};
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use std::sync::Arc;
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use store::{Error as StoreError, Store};
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use types::{
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Attestation, BeaconBlock, BeaconState, BeaconStateError, Epoch, EthSpec, Hash256, Slot,
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Attestation, BeaconBlock, BeaconState, BeaconStateError, Checkpoint, EthSpec, Hash256, Slot,
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};
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type Result<T> = std::result::Result<T, Error>;
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@@ -16,6 +17,7 @@ pub enum Error {
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BackendError(String),
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BeaconStateError(BeaconStateError),
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StoreError(StoreError),
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BeaconChainError(Box<BeaconChainError>),
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}
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pub struct ForkChoice<T: BeaconChainTypes> {
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@@ -26,6 +28,10 @@ pub struct ForkChoice<T: BeaconChainTypes> {
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/// Does not necessarily need to be the _actual_ genesis, it suffices to be the finalized root
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/// whenever the struct was instantiated.
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genesis_block_root: Hash256,
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/// The fork choice rule's current view of the justified checkpoint.
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justified_checkpoint: RwLock<Checkpoint>,
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/// The best justified checkpoint we've seen, which may be ahead of `justified_checkpoint`.
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best_justified_checkpoint: RwLock<Checkpoint>,
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}
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impl<T: BeaconChainTypes> ForkChoice<T> {
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@@ -38,38 +44,86 @@ impl<T: BeaconChainTypes> ForkChoice<T> {
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genesis_block: &BeaconBlock<T::EthSpec>,
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genesis_block_root: Hash256,
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) -> Self {
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let genesis_slot = genesis_block.slot;
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let justified_checkpoint = Checkpoint {
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epoch: genesis_slot.epoch(T::EthSpec::slots_per_epoch()),
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root: genesis_block_root,
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};
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Self {
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store: store.clone(),
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backend: T::LmdGhost::new(store, genesis_block, genesis_block_root),
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genesis_block_root,
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justified_checkpoint: RwLock::new(justified_checkpoint.clone()),
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best_justified_checkpoint: RwLock::new(justified_checkpoint),
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}
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}
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/// Determine whether the fork choice's view of the justified checkpoint should be updated.
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///
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/// To prevent the bouncing attack, an update is allowed only in these conditions:
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///
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/// * We're in the first SAFE_SLOTS_TO_UPDATE_JUSTIFIED slots of the epoch, or
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/// * The new justified checkpoint is a descendant of the current justified checkpoint
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fn should_update_justified_checkpoint(
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&self,
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chain: &BeaconChain<T>,
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new_justified_checkpoint: &Checkpoint,
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) -> Result<bool> {
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if Self::compute_slots_since_epoch_start(chain.slot()?)
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< chain.spec.safe_slots_to_update_justified
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{
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return Ok(true);
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}
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let justified_checkpoint = self.justified_checkpoint.read().clone();
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let current_justified_block = chain
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.get_block(&justified_checkpoint.root)?
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.ok_or_else(|| Error::MissingBlock(justified_checkpoint.root))?;
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let new_justified_block = chain
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.get_block(&new_justified_checkpoint.root)?
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.ok_or_else(|| Error::MissingBlock(new_justified_checkpoint.root))?;
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let slots_per_epoch = T::EthSpec::slots_per_epoch();
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Ok(
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new_justified_block.slot > justified_checkpoint.epoch.start_slot(slots_per_epoch)
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&& chain.get_ancestor_block_root(
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new_justified_checkpoint.root,
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current_justified_block.slot,
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)? == Some(justified_checkpoint.root),
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)
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}
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/// Calculate how far `slot` lies from the start of its epoch.
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fn compute_slots_since_epoch_start(slot: Slot) -> u64 {
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let slots_per_epoch = T::EthSpec::slots_per_epoch();
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(slot - slot.epoch(slots_per_epoch).start_slot(slots_per_epoch)).as_u64()
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}
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/// Run the fork choice rule to determine the head.
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pub fn find_head(&self, chain: &BeaconChain<T>) -> Result<Hash256> {
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let timer = metrics::start_timer(&metrics::FORK_CHOICE_FIND_HEAD_TIMES);
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let start_slot = |epoch: Epoch| epoch.start_slot(T::EthSpec::slots_per_epoch());
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// From the specification:
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//
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// Let justified_head be the descendant of finalized_head with the highest epoch that has
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// been justified for at least 1 epoch ... If no such descendant exists,
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// set justified_head to finalized_head.
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let (start_state, start_block_root, start_block_slot) = {
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let state = &chain.head().beacon_state;
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// Check if we should update our view of the justified checkpoint.
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// Doing this check here should be quasi-equivalent to the update in the `on_tick`
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// function of the spec, so long as `find_head` is called at least once during the first
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// SAFE_SLOTS_TO_UPDATE_JUSTIFIED slots.
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let best_justified_checkpoint = self.best_justified_checkpoint.read();
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if self.should_update_justified_checkpoint(chain, &best_justified_checkpoint)? {
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*self.justified_checkpoint.write() = best_justified_checkpoint.clone();
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}
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let (block_root, block_slot) =
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if state.current_epoch() + 1 > state.current_justified_checkpoint.epoch {
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(
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state.current_justified_checkpoint.root,
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start_slot(state.current_justified_checkpoint.epoch),
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)
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} else {
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(
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state.finalized_checkpoint.root,
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start_slot(state.finalized_checkpoint.epoch),
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)
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};
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let current_justified_checkpoint = self.justified_checkpoint.read().clone();
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let (block_root, block_justified_slot) = (
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current_justified_checkpoint.root,
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current_justified_checkpoint
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.epoch
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.start_slot(T::EthSpec::slots_per_epoch()),
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);
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let block = chain
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.store
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@@ -83,12 +137,17 @@ impl<T: BeaconChainTypes> ForkChoice<T> {
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block_root
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};
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let state = chain
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.store
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.get::<BeaconState<T::EthSpec>>(&block.state_root)?
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let mut state = chain
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.get_state(&block.state_root)?
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.ok_or_else(|| Error::MissingState(block.state_root))?;
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(state, block_root, block_slot)
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// Fast-forward the state to the start slot of the epoch where it was justified.
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for _ in block.slot.as_u64()..block_justified_slot.as_u64() {
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per_slot_processing(&mut state, &chain.spec)
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.map_err(|e| BeaconChainError::SlotProcessingError(e))?
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}
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(state, block_root, block_justified_slot)
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};
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// A function that returns the weight for some validator index.
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@@ -111,10 +170,11 @@ impl<T: BeaconChainTypes> ForkChoice<T> {
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/// Process all attestations in the given `block`.
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///
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/// Assumes the block (and therefore it's attestations) are valid. It is a logic error to
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/// Assumes the block (and therefore its attestations) are valid. It is a logic error to
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/// provide an invalid block.
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pub fn process_block(
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&self,
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chain: &BeaconChain<T>,
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state: &BeaconState<T::EthSpec>,
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block: &BeaconBlock<T::EthSpec>,
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block_root: Hash256,
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@@ -137,6 +197,16 @@ impl<T: BeaconChainTypes> ForkChoice<T> {
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}
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}
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// Check if we should update our view of the justified checkpoint
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if state.current_justified_checkpoint.epoch > self.justified_checkpoint.read().epoch {
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*self.best_justified_checkpoint.write() = state.current_justified_checkpoint.clone();
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if self
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.should_update_justified_checkpoint(chain, &state.current_justified_checkpoint)?
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{
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*self.justified_checkpoint.write() = state.current_justified_checkpoint.clone();
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}
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}
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// This does not apply a vote to the block, it just makes fork choice aware of the block so
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// it can still be identified as the head even if it doesn't have any votes.
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//
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@@ -228,6 +298,12 @@ impl From<BeaconStateError> for Error {
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}
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}
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impl From<BeaconChainError> for Error {
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fn from(e: BeaconChainError) -> Error {
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Error::BeaconChainError(Box::new(e))
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}
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}
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impl From<StoreError> for Error {
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fn from(e: StoreError) -> Error {
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Error::StoreError(e)
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@@ -8,6 +8,7 @@ edition = "2018"
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parking_lot = "0.9.0"
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store = { path = "../../beacon_node/store" }
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types = { path = "../types" }
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itertools = "0.8.1"
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[dev-dependencies]
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criterion = "0.3.0"
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@@ -49,7 +49,7 @@ pub trait LmdGhost<S: Store, E: EthSpec>: Send + Sync {
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/// Runs an integrity verification function on fork choice algorithm.
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///
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/// Returns `Ok(())` if the underlying fork choice has maintained it's integrity,
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/// Returns `Ok(())` if the underlying fork choice has maintained its integrity,
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/// `Err(description)` otherwise.
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fn verify_integrity(&self) -> Result<()>;
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}
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@@ -4,6 +4,7 @@
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//!
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//! This implementation is incomplete and has known bugs. Do not use in production.
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use super::{LmdGhost, Result as SuperResult};
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use itertools::Itertools;
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use parking_lot::RwLock;
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use std::collections::HashMap;
|
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use std::fmt;
|
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@@ -20,6 +21,7 @@ pub enum Error {
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MissingBlock(Hash256),
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MissingState(Hash256),
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MissingChild(Hash256),
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MissingSuccessor(Hash256, Hash256),
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NotInTree(Hash256),
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NoCommonAncestor((Hash256, Hash256)),
|
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StoreError(StoreError),
|
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@@ -177,8 +179,8 @@ where
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if current_hash != subtree_hash {
|
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let children = self.get_node(current_hash)?.children.clone();
|
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|
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for child_hash in children {
|
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self.retain_subtree(child_hash, subtree_hash)?;
|
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for child in children {
|
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self.retain_subtree(child.hash, subtree_hash)?;
|
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}
|
||||
|
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self.nodes.remove(¤t_hash);
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@@ -239,7 +241,7 @@ where
|
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let _root_weight = self.update_weight(start_block_root, weight_fn)?;
|
||||
|
||||
let start_node = self.get_node(start_block_root)?;
|
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let head_node = self.find_head_from(start_node)?;
|
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let head_node = self.find_head_from(start_node, start_block_slot)?;
|
||||
|
||||
Ok(head_node.block_hash)
|
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}
|
||||
@@ -251,31 +253,32 @@ where
|
||||
}
|
||||
}
|
||||
|
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fn find_head_from<'a>(&'a self, start_node: &'a Node) -> Result<&'a Node> {
|
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if start_node.does_not_have_children() {
|
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// Corresponds to the loop in `get_head` in the spec.
|
||||
fn find_head_from<'a>(
|
||||
&'a self,
|
||||
start_node: &'a Node,
|
||||
justified_slot: Slot,
|
||||
) -> Result<&'a Node> {
|
||||
let children = start_node
|
||||
.children
|
||||
.iter()
|
||||
// This check is primarily for the first iteration, where we must ensure that
|
||||
// we only consider votes that were made after the last justified checkpoint.
|
||||
.filter(|c| c.successor_slot > justified_slot)
|
||||
.map(|c| self.get_node(c.hash))
|
||||
.collect::<Result<Vec<&Node>>>()?;
|
||||
|
||||
if children.is_empty() {
|
||||
Ok(start_node)
|
||||
} else {
|
||||
let children = start_node
|
||||
.children
|
||||
.iter()
|
||||
.map(|hash| self.get_node(*hash))
|
||||
.collect::<Result<Vec<&Node>>>()?;
|
||||
|
||||
// TODO: check if `max_by` is `O(n^2)`.
|
||||
let best_child = children
|
||||
.iter()
|
||||
.max_by(|a, b| {
|
||||
if a.weight != b.weight {
|
||||
a.weight.cmp(&b.weight)
|
||||
} else {
|
||||
a.block_hash.cmp(&b.block_hash)
|
||||
}
|
||||
})
|
||||
.max_by_key(|child| (child.weight, child.block_hash))
|
||||
// There can only be no maximum if there are no children. This code path is guarded
|
||||
// against that condition.
|
||||
.expect("There must be a maximally weighted node.");
|
||||
|
||||
self.find_head_from(best_child)
|
||||
self.find_head_from(best_child, justified_slot)
|
||||
}
|
||||
}
|
||||
|
||||
@@ -288,8 +291,8 @@ where
|
||||
|
||||
let mut weight = 0;
|
||||
|
||||
for &child in &node.children {
|
||||
weight += self.update_weight(child, weight_fn)?;
|
||||
for child in &node.children {
|
||||
weight += self.update_weight(child.hash, weight_fn)?;
|
||||
}
|
||||
|
||||
for &voter in &node.voters {
|
||||
@@ -323,13 +326,13 @@ where
|
||||
//
|
||||
// Load the child of the node and set it's parent to be the parent of this
|
||||
// node (viz., graft the node's child to the node's parent)
|
||||
let child = self.get_mut_node(node.children[0])?;
|
||||
let child = self.get_mut_node(node.children[0].hash)?;
|
||||
child.parent_hash = node.parent_hash;
|
||||
|
||||
// Graft the parent of this node to it's child.
|
||||
if let Some(parent_hash) = node.parent_hash {
|
||||
let parent = self.get_mut_node(parent_hash)?;
|
||||
parent.replace_child(node.block_hash, node.children[0])?;
|
||||
parent.replace_child_hash(node.block_hash, node.children[0].hash)?;
|
||||
}
|
||||
|
||||
self.nodes.remove(&vote.hash);
|
||||
@@ -376,15 +379,16 @@ where
|
||||
let node = node.clone();
|
||||
|
||||
if let Some(parent_hash) = node.parent_hash {
|
||||
if (node.children.len() == 1) && !node.has_votes() {
|
||||
let child_hash = node.children[0];
|
||||
if node.children.len() == 1 && !node.has_votes() {
|
||||
let child = &node.children[0];
|
||||
|
||||
// Graft the single descendant `node` to the `parent` of node.
|
||||
self.get_mut_node(child_hash)?.parent_hash = Some(parent_hash);
|
||||
self.get_mut_node(child.hash)?.parent_hash = Some(parent_hash);
|
||||
|
||||
// Detach `node` from `parent`, replacing it with `child`.
|
||||
// Preserve the parent's direct descendant slot.
|
||||
self.get_mut_node(parent_hash)?
|
||||
.replace_child(hash, child_hash)?;
|
||||
.replace_child_hash(hash, child.hash)?;
|
||||
|
||||
true
|
||||
} else {
|
||||
@@ -442,6 +446,40 @@ where
|
||||
Ok(())
|
||||
}
|
||||
|
||||
/// Find the direct successor block of `ancestor` if `descendant` is a descendant.
|
||||
fn find_ancestor_successor_opt(
|
||||
&self,
|
||||
ancestor: Hash256,
|
||||
descendant: Hash256,
|
||||
) -> Result<Option<Hash256>> {
|
||||
Ok(std::iter::once(descendant)
|
||||
.chain(
|
||||
self.iter_ancestors(descendant)?
|
||||
.take_while(|(_, slot)| *slot >= self.root_slot())
|
||||
.map(|(block_hash, _)| block_hash),
|
||||
)
|
||||
.tuple_windows()
|
||||
.find_map(|(successor, block_hash)| {
|
||||
if block_hash == ancestor {
|
||||
Some(successor)
|
||||
} else {
|
||||
None
|
||||
}
|
||||
}))
|
||||
}
|
||||
|
||||
/// Same as `find_ancestor_successor_opt` but will return an error instead of an option.
|
||||
fn find_ancestor_successor(&self, ancestor: Hash256, descendant: Hash256) -> Result<Hash256> {
|
||||
self.find_ancestor_successor_opt(ancestor, descendant)?
|
||||
.ok_or_else(|| Error::MissingSuccessor(ancestor, descendant))
|
||||
}
|
||||
|
||||
/// Look up the successor of the given `ancestor`, returning the slot of that block.
|
||||
fn find_ancestor_successor_slot(&self, ancestor: Hash256, descendant: Hash256) -> Result<Slot> {
|
||||
let successor_hash = self.find_ancestor_successor(ancestor, descendant)?;
|
||||
Ok(self.get_block(successor_hash)?.slot)
|
||||
}
|
||||
|
||||
/// Add `node` to the reduced tree, returning an error if `node` is not rooted in the tree.
|
||||
fn add_node(&mut self, mut node: Node) -> Result<()> {
|
||||
// Find the highest (by slot) ancestor of the given node in the reduced tree.
|
||||
@@ -460,7 +498,9 @@ where
|
||||
// `node` to it.
|
||||
// 3. Graft `node` to an existing node.
|
||||
if !prev_in_tree.children.is_empty() {
|
||||
for &child_hash in &prev_in_tree.children {
|
||||
for child_link in &prev_in_tree.children {
|
||||
let child_hash = child_link.hash;
|
||||
|
||||
// 1. Graft the new node between two existing nodes.
|
||||
//
|
||||
// If `node` is a descendant of `prev_in_tree` but an ancestor of a child connected to
|
||||
@@ -468,19 +508,20 @@ where
|
||||
//
|
||||
// This means that `node` can be grafted between `prev_in_tree` and the child that is a
|
||||
// descendant of both `node` and `prev_in_tree`.
|
||||
if self
|
||||
.iter_ancestors(child_hash)?
|
||||
.take_while(|(_, slot)| *slot >= self.root_slot())
|
||||
.any(|(ancestor, _slot)| ancestor == node.block_hash)
|
||||
if let Some(successor) =
|
||||
self.find_ancestor_successor_opt(node.block_hash, child_hash)?
|
||||
{
|
||||
let child = self.get_mut_node(child_hash)?;
|
||||
|
||||
// Graft `child` to `node`.
|
||||
child.parent_hash = Some(node.block_hash);
|
||||
// Graft `node` to `child`.
|
||||
node.children.push(child_hash);
|
||||
node.children.push(ChildLink {
|
||||
hash: child_hash,
|
||||
successor_slot: self.get_block(successor)?.slot,
|
||||
});
|
||||
// Detach `child` from `prev_in_tree`, replacing it with `node`.
|
||||
prev_in_tree.replace_child(child_hash, node.block_hash)?;
|
||||
prev_in_tree.replace_child_hash(child_hash, node.block_hash)?;
|
||||
// Graft `node` to `prev_in_tree`.
|
||||
node.parent_hash = Some(prev_in_tree.block_hash);
|
||||
|
||||
@@ -495,7 +536,8 @@ where
|
||||
// any of the children of `prev_in_tree`, we know that `node` is on a different fork to
|
||||
// all of the children of `prev_in_tree`.
|
||||
if node.parent_hash.is_none() {
|
||||
for &child_hash in &prev_in_tree.children {
|
||||
for child_link in &prev_in_tree.children {
|
||||
let child_hash = child_link.hash;
|
||||
// Find the highest (by slot) common ancestor between `node` and `child`.
|
||||
//
|
||||
// The common ancestor is the last block before `node` and `child` forked.
|
||||
@@ -506,24 +548,37 @@ where
|
||||
// must add this new block into the tree (because it is a decision node
|
||||
// between two forks).
|
||||
if ancestor_hash != prev_in_tree.block_hash {
|
||||
let child = self.get_mut_node(child_hash)?;
|
||||
|
||||
// Create a new `common_ancestor` node which represents the `ancestor_hash`
|
||||
// block, has `prev_in_tree` as the parent and has both `node` and `child`
|
||||
// as children.
|
||||
let common_ancestor = Node {
|
||||
block_hash: ancestor_hash,
|
||||
parent_hash: Some(prev_in_tree.block_hash),
|
||||
children: vec![node.block_hash, child_hash],
|
||||
children: vec![
|
||||
ChildLink {
|
||||
hash: node.block_hash,
|
||||
successor_slot: self.find_ancestor_successor_slot(
|
||||
ancestor_hash,
|
||||
node.block_hash,
|
||||
)?,
|
||||
},
|
||||
ChildLink {
|
||||
hash: child_hash,
|
||||
successor_slot: self
|
||||
.find_ancestor_successor_slot(ancestor_hash, child_hash)?,
|
||||
},
|
||||
],
|
||||
..Node::default()
|
||||
};
|
||||
|
||||
let child = self.get_mut_node(child_hash)?;
|
||||
|
||||
// Graft `child` and `node` to `common_ancestor`.
|
||||
child.parent_hash = Some(common_ancestor.block_hash);
|
||||
node.parent_hash = Some(common_ancestor.block_hash);
|
||||
|
||||
// Detach `child` from `prev_in_tree`, replacing it with `common_ancestor`.
|
||||
prev_in_tree.replace_child(child_hash, common_ancestor.block_hash)?;
|
||||
prev_in_tree.replace_child_hash(child_hash, common_ancestor.block_hash)?;
|
||||
|
||||
// Store the new `common_ancestor` node.
|
||||
self.nodes
|
||||
@@ -540,7 +595,11 @@ where
|
||||
//
|
||||
// Graft `node` to `prev_in_tree` and `prev_in_tree` to `node`
|
||||
node.parent_hash = Some(prev_in_tree.block_hash);
|
||||
prev_in_tree.children.push(node.block_hash);
|
||||
prev_in_tree.children.push(ChildLink {
|
||||
hash: node.block_hash,
|
||||
successor_slot: self
|
||||
.find_ancestor_successor_slot(prev_in_tree.block_hash, node.block_hash)?,
|
||||
});
|
||||
}
|
||||
|
||||
// Update `prev_in_tree`. A mutable reference was not maintained to satisfy the borrow
|
||||
@@ -655,7 +714,17 @@ where
|
||||
|
||||
node.children
|
||||
.iter()
|
||||
.map(|child| verify_node_exists(*child, "child_must_exist".to_string()))
|
||||
.map(|child| {
|
||||
verify_node_exists(child.hash, "child_must_exist".to_string())?;
|
||||
|
||||
if self.find_ancestor_successor_slot(node.block_hash, child.hash)?
|
||||
== child.successor_slot
|
||||
{
|
||||
Ok(())
|
||||
} else {
|
||||
Err("successor slot on child link is incorrect".to_string())
|
||||
}
|
||||
})
|
||||
.collect::<std::result::Result<(), String>>()?;
|
||||
|
||||
verify_node_exists(node.block_hash, "block hash must exist".to_string())?;
|
||||
@@ -698,25 +767,35 @@ where
|
||||
|
||||
#[derive(Default, Clone, Debug)]
|
||||
pub struct Node {
|
||||
/// Hash of the parent node in the reduced tree (not necessarily parent block).
|
||||
pub parent_hash: Option<Hash256>,
|
||||
pub children: Vec<Hash256>,
|
||||
pub children: Vec<ChildLink>,
|
||||
pub weight: u64,
|
||||
pub block_hash: Hash256,
|
||||
pub voters: Vec<usize>,
|
||||
}
|
||||
|
||||
impl Node {
|
||||
pub fn does_not_have_children(&self) -> bool {
|
||||
self.children.is_empty()
|
||||
}
|
||||
#[derive(Default, Clone, Debug)]
|
||||
pub struct ChildLink {
|
||||
/// Hash of the child block (may not be a direct descendant).
|
||||
pub hash: Hash256,
|
||||
/// Slot of the block which is a direct descendant on the chain leading to `hash`.
|
||||
///
|
||||
/// Node <--- Successor <--- ... <--- Child
|
||||
pub successor_slot: Slot,
|
||||
}
|
||||
|
||||
pub fn replace_child(&mut self, old: Hash256, new: Hash256) -> Result<()> {
|
||||
impl Node {
|
||||
/// Replace a child with a new child, whilst preserving the successor slot.
|
||||
///
|
||||
/// The new child should have the same ancestor successor block as the old one.
|
||||
pub fn replace_child_hash(&mut self, old: Hash256, new: Hash256) -> Result<()> {
|
||||
let i = self
|
||||
.children
|
||||
.iter()
|
||||
.position(|&c| c == old)
|
||||
.position(|c| c.hash == old)
|
||||
.ok_or_else(|| Error::MissingChild(old))?;
|
||||
self.children[i] = new;
|
||||
self.children[i].hash = new;
|
||||
|
||||
Ok(())
|
||||
}
|
||||
@@ -725,7 +804,7 @@ impl Node {
|
||||
let i = self
|
||||
.children
|
||||
.iter()
|
||||
.position(|&c| c == child)
|
||||
.position(|c| c.hash == child)
|
||||
.ok_or_else(|| Error::MissingChild(child))?;
|
||||
|
||||
self.children.remove(i);
|
||||
|
||||
@@ -45,7 +45,9 @@ struct ForkedHarness {
|
||||
pub genesis_block: BeaconBlock<TestEthSpec>,
|
||||
pub honest_head: RootAndSlot,
|
||||
pub faulty_head: RootAndSlot,
|
||||
/// Honest roots in reverse order (slot high to low)
|
||||
pub honest_roots: Vec<RootAndSlot>,
|
||||
/// Faulty roots in reverse order (slot high to low)
|
||||
pub faulty_roots: Vec<RootAndSlot>,
|
||||
}
|
||||
|
||||
@@ -222,7 +224,7 @@ fn single_voter_persistent_instance_reverse_order() {
|
||||
"New tree should have integrity"
|
||||
);
|
||||
|
||||
for (root, slot) in harness.honest_roots.iter().rev() {
|
||||
for (root, slot) in &harness.honest_roots {
|
||||
lmd.process_attestation(0, *root, *slot)
|
||||
.expect("fork choice should accept attestations to honest roots in reverse");
|
||||
|
||||
@@ -234,11 +236,15 @@ fn single_voter_persistent_instance_reverse_order() {
|
||||
}
|
||||
|
||||
// The honest head should be selected.
|
||||
let (head_root, head_slot) = harness.honest_roots.first().unwrap();
|
||||
let (finalized_root, _) = harness.honest_roots.last().unwrap();
|
||||
let (head_root, _) = harness.honest_roots.first().unwrap();
|
||||
let (finalized_root, finalized_slot) = harness.honest_roots.last().unwrap();
|
||||
|
||||
assert_eq!(
|
||||
lmd.find_head(*head_slot, *finalized_root, ForkedHarness::weight_function),
|
||||
lmd.find_head(
|
||||
*finalized_slot,
|
||||
*finalized_root,
|
||||
ForkedHarness::weight_function
|
||||
),
|
||||
Ok(*head_root),
|
||||
"Honest head should be selected"
|
||||
);
|
||||
@@ -250,7 +256,7 @@ fn single_voter_persistent_instance_reverse_order() {
|
||||
fn single_voter_many_instance_honest_blocks_voting_forwards() {
|
||||
let harness = &FORKED_HARNESS;
|
||||
|
||||
for (root, slot) in &harness.honest_roots {
|
||||
for (root, slot) in harness.honest_roots.iter().rev() {
|
||||
let lmd = harness.new_fork_choice();
|
||||
lmd.process_attestation(0, *root, *slot)
|
||||
.expect("fork choice should accept attestations to honest roots");
|
||||
@@ -269,7 +275,7 @@ fn single_voter_many_instance_honest_blocks_voting_in_reverse() {
|
||||
let harness = &FORKED_HARNESS;
|
||||
|
||||
// Same as above, but in reverse order (votes on the highest honest block first).
|
||||
for (root, slot) in harness.honest_roots.iter().rev() {
|
||||
for (root, slot) in &harness.honest_roots {
|
||||
let lmd = harness.new_fork_choice();
|
||||
lmd.process_attestation(0, *root, *slot)
|
||||
.expect("fork choice should accept attestations to honest roots in reverse");
|
||||
@@ -288,7 +294,7 @@ fn single_voter_many_instance_honest_blocks_voting_in_reverse() {
|
||||
fn single_voter_many_instance_faulty_blocks_voting_forwards() {
|
||||
let harness = &FORKED_HARNESS;
|
||||
|
||||
for (root, slot) in &harness.faulty_roots {
|
||||
for (root, slot) in harness.faulty_roots.iter().rev() {
|
||||
let lmd = harness.new_fork_choice();
|
||||
lmd.process_attestation(0, *root, *slot)
|
||||
.expect("fork choice should accept attestations to faulty roots");
|
||||
@@ -306,7 +312,7 @@ fn single_voter_many_instance_faulty_blocks_voting_forwards() {
|
||||
fn single_voter_many_instance_faulty_blocks_voting_in_reverse() {
|
||||
let harness = &FORKED_HARNESS;
|
||||
|
||||
for (root, slot) in harness.faulty_roots.iter().rev() {
|
||||
for (root, slot) in &harness.faulty_roots {
|
||||
let lmd = harness.new_fork_choice();
|
||||
lmd.process_attestation(0, *root, *slot)
|
||||
.expect("fork choice should accept attestations to faulty roots in reverse");
|
||||
@@ -319,6 +325,49 @@ fn single_voter_many_instance_faulty_blocks_voting_in_reverse() {
|
||||
}
|
||||
}
|
||||
|
||||
/// Ensure that votes with slots before the justified slot are not counted.
|
||||
#[test]
|
||||
fn discard_votes_before_justified_slot() {
|
||||
let harness = &FORKED_HARNESS;
|
||||
|
||||
let lmd = harness.new_fork_choice();
|
||||
|
||||
let (genesis_root, genesis_slot) = *harness.honest_roots.last().unwrap();
|
||||
|
||||
dbg!(&harness.honest_roots);
|
||||
|
||||
// Add attestations from all validators for all honest blocks.
|
||||
for (root, slot) in harness.honest_roots.iter().rev() {
|
||||
for i in 0..VALIDATOR_COUNT {
|
||||
lmd.process_attestation(i, *root, *slot)
|
||||
.expect("should accept attestations in increasing order");
|
||||
}
|
||||
|
||||
// Head starting from 0 checkpoint (genesis) should be current root
|
||||
assert_eq!(
|
||||
lmd.find_head(genesis_slot, genesis_root, ForkedHarness::weight_function),
|
||||
Ok(*root),
|
||||
"Honest head should be selected"
|
||||
);
|
||||
|
||||
assert_eq!(
|
||||
lmd.find_head(
|
||||
genesis_slot + 1,
|
||||
genesis_root,
|
||||
ForkedHarness::weight_function
|
||||
),
|
||||
Ok(genesis_root)
|
||||
);
|
||||
}
|
||||
|
||||
let head = harness.harness.chain.head();
|
||||
|
||||
dbg!(&harness.honest_roots);
|
||||
dbg!(head.beacon_state.current_justified_checkpoint);
|
||||
|
||||
// assert!(false);
|
||||
}
|
||||
|
||||
/// Ensures that the finalized root can be set to all values in `roots`.
|
||||
fn test_update_finalized_root(roots: &[(Hash256, Slot)]) {
|
||||
let harness = &FORKED_HARNESS;
|
||||
|
||||
@@ -84,6 +84,11 @@ pub struct ChainSpec {
|
||||
domain_deposit: u32,
|
||||
domain_voluntary_exit: u32,
|
||||
|
||||
/*
|
||||
* Fork choice
|
||||
*/
|
||||
pub safe_slots_to_update_justified: u64,
|
||||
|
||||
pub boot_nodes: Vec<String>,
|
||||
pub network_id: u8,
|
||||
}
|
||||
@@ -184,6 +189,11 @@ impl ChainSpec {
|
||||
domain_deposit: 3,
|
||||
domain_voluntary_exit: 4,
|
||||
|
||||
/*
|
||||
* Fork choice
|
||||
*/
|
||||
safe_slots_to_update_justified: 8,
|
||||
|
||||
/*
|
||||
* Network specific
|
||||
*/
|
||||
|
||||
Reference in New Issue
Block a user