lighthouse/consensus/state_processing/src/per_block_processing.rs
Pawan Dhananjay 4499adc7fd Check proposer index during block production (#2740)
## Issue Addressed

Resolves #2612 

## Proposed Changes

Implements both the checks mentioned in the original issue. 
1. Verifies the `randao_reveal` in the beacon node
2. Cross checks the proposer index after getting back the block from the beacon node.

## Additional info
The block production time increases by ~10x because of the signature verification on the beacon node (based on the `beacon_block_production_process_seconds` metric) when running on a local testnet.
2021-11-01 07:44:40 +00:00

286 lines
9.5 KiB
Rust

use errors::{BlockOperationError, BlockProcessingError, HeaderInvalid};
use rayon::prelude::*;
use safe_arith::{ArithError, SafeArith};
use signature_sets::{block_proposal_signature_set, get_pubkey_from_state, randao_signature_set};
use std::borrow::Cow;
use tree_hash::TreeHash;
use types::*;
pub use self::verify_attester_slashing::{
get_slashable_indices, get_slashable_indices_modular, verify_attester_slashing,
};
pub use self::verify_proposer_slashing::verify_proposer_slashing;
pub use altair::sync_committee::process_sync_aggregate;
pub use block_signature_verifier::{BlockSignatureVerifier, ParallelSignatureSets};
pub use is_valid_indexed_attestation::is_valid_indexed_attestation;
pub use process_operations::process_operations;
pub use verify_attestation::{
verify_attestation_for_block_inclusion, verify_attestation_for_state,
};
pub use verify_deposit::{
get_existing_validator_index, verify_deposit_merkle_proof, verify_deposit_signature,
};
pub use verify_exit::verify_exit;
pub mod altair;
pub mod block_signature_verifier;
pub mod errors;
mod is_valid_indexed_attestation;
pub mod process_operations;
pub mod signature_sets;
pub mod tests;
mod verify_attestation;
mod verify_attester_slashing;
mod verify_deposit;
mod verify_exit;
mod verify_proposer_slashing;
#[cfg(feature = "arbitrary-fuzz")]
use arbitrary::Arbitrary;
/// The strategy to be used when validating the block's signatures.
#[cfg_attr(feature = "arbitrary-fuzz", derive(Arbitrary))]
#[derive(PartialEq, Clone, Copy)]
pub enum BlockSignatureStrategy {
/// Do not validate any signature. Use with caution.
NoVerification,
/// Validate each signature individually, as its object is being processed.
VerifyIndividual,
/// Validate only the randao reveal signature.
VerifyRandao,
/// Verify all signatures in bulk at the beginning of block processing.
VerifyBulk,
}
/// The strategy to be used when validating the block's signatures.
#[cfg_attr(feature = "arbitrary-fuzz", derive(Arbitrary))]
#[derive(PartialEq, Clone, Copy)]
pub enum VerifySignatures {
/// Validate all signatures encountered.
True,
/// Do not validate any signature. Use with caution.
False,
}
impl VerifySignatures {
pub fn is_true(self) -> bool {
self == VerifySignatures::True
}
}
/// Updates the state for a new block, whilst validating that the block is valid, optionally
/// checking the block proposer signature.
///
/// Returns `Ok(())` if the block is valid and the state was successfully updated. Otherwise
/// returns an error describing why the block was invalid or how the function failed to execute.
///
/// If `block_root` is `Some`, this root is used for verification of the proposer's signature. If it
/// is `None` the signing root is computed from scratch. This parameter only exists to avoid
/// re-calculating the root when it is already known. Note `block_root` should be equal to the
/// tree hash root of the block, NOT the signing root of the block. This function takes
/// care of mixing in the domain.
pub fn per_block_processing<T: EthSpec>(
state: &mut BeaconState<T>,
signed_block: &SignedBeaconBlock<T>,
block_root: Option<Hash256>,
block_signature_strategy: BlockSignatureStrategy,
spec: &ChainSpec,
) -> Result<(), BlockProcessingError> {
let block = signed_block.message();
// Verify that the `SignedBeaconBlock` instantiation matches the fork at `signed_block.slot()`.
signed_block
.fork_name(spec)
.map_err(BlockProcessingError::InconsistentBlockFork)?;
// Verify that the `BeaconState` instantiation matches the fork at `state.slot()`.
state
.fork_name(spec)
.map_err(BlockProcessingError::InconsistentStateFork)?;
let verify_signatures = match block_signature_strategy {
BlockSignatureStrategy::VerifyBulk => {
// Verify all signatures in the block at once.
block_verify!(
BlockSignatureVerifier::verify_entire_block(
state,
|i| get_pubkey_from_state(state, i),
|pk_bytes| pk_bytes.decompress().ok().map(Cow::Owned),
signed_block,
block_root,
spec
)
.is_ok(),
BlockProcessingError::BulkSignatureVerificationFailed
);
VerifySignatures::False
}
BlockSignatureStrategy::VerifyIndividual => VerifySignatures::True,
BlockSignatureStrategy::NoVerification => VerifySignatures::False,
BlockSignatureStrategy::VerifyRandao => VerifySignatures::False,
};
let proposer_index = process_block_header(state, block, spec)?;
if verify_signatures.is_true() {
verify_block_signature(state, signed_block, block_root, spec)?;
}
let verify_randao = if let BlockSignatureStrategy::VerifyRandao = block_signature_strategy {
VerifySignatures::True
} else {
verify_signatures
};
// Ensure the current and previous epoch caches are built.
state.build_committee_cache(RelativeEpoch::Previous, spec)?;
state.build_committee_cache(RelativeEpoch::Current, spec)?;
process_randao(state, block, verify_randao, spec)?;
process_eth1_data(state, block.body().eth1_data())?;
process_operations(state, block.body(), proposer_index, verify_signatures, spec)?;
if let BeaconBlockRef::Altair(inner) = block {
process_sync_aggregate(
state,
&inner.body.sync_aggregate,
proposer_index,
verify_signatures,
spec,
)?;
}
Ok(())
}
/// Processes the block header, returning the proposer index.
pub fn process_block_header<T: EthSpec>(
state: &mut BeaconState<T>,
block: BeaconBlockRef<'_, T>,
spec: &ChainSpec,
) -> Result<u64, BlockOperationError<HeaderInvalid>> {
// Verify that the slots match
verify!(
block.slot() == state.slot(),
HeaderInvalid::StateSlotMismatch
);
// Verify that the block is newer than the latest block header
verify!(
block.slot() > state.latest_block_header().slot,
HeaderInvalid::OlderThanLatestBlockHeader {
block_slot: block.slot(),
latest_block_header_slot: state.latest_block_header().slot,
}
);
// Verify that proposer index is the correct index
let proposer_index = block.proposer_index() as usize;
let state_proposer_index = state.get_beacon_proposer_index(block.slot(), spec)?;
verify!(
proposer_index == state_proposer_index,
HeaderInvalid::ProposerIndexMismatch {
block_proposer_index: proposer_index,
state_proposer_index,
}
);
let expected_previous_block_root = state.latest_block_header().tree_hash_root();
verify!(
block.parent_root() == expected_previous_block_root,
HeaderInvalid::ParentBlockRootMismatch {
state: expected_previous_block_root,
block: block.parent_root(),
}
);
*state.latest_block_header_mut() = block.temporary_block_header();
// Verify proposer is not slashed
verify!(
!state.get_validator(proposer_index)?.slashed,
HeaderInvalid::ProposerSlashed(proposer_index)
);
Ok(block.proposer_index())
}
/// Verifies the signature of a block.
///
/// Spec v0.12.1
pub fn verify_block_signature<T: EthSpec>(
state: &BeaconState<T>,
block: &SignedBeaconBlock<T>,
block_root: Option<Hash256>,
spec: &ChainSpec,
) -> Result<(), BlockOperationError<HeaderInvalid>> {
verify!(
block_proposal_signature_set(
state,
|i| get_pubkey_from_state(state, i),
block,
block_root,
spec
)?
.verify(),
HeaderInvalid::ProposalSignatureInvalid
);
Ok(())
}
/// Verifies the `randao_reveal` against the block's proposer pubkey and updates
/// `state.latest_randao_mixes`.
pub fn process_randao<T: EthSpec>(
state: &mut BeaconState<T>,
block: BeaconBlockRef<'_, T>,
verify_signatures: VerifySignatures,
spec: &ChainSpec,
) -> Result<(), BlockProcessingError> {
if verify_signatures.is_true() {
// Verify RANDAO reveal signature.
block_verify!(
randao_signature_set(state, |i| get_pubkey_from_state(state, i), block, spec)?.verify(),
BlockProcessingError::RandaoSignatureInvalid
);
}
// Update the current epoch RANDAO mix.
state.update_randao_mix(state.current_epoch(), block.body().randao_reveal())?;
Ok(())
}
/// Update the `state.eth1_data_votes` based upon the `eth1_data` provided.
pub fn process_eth1_data<T: EthSpec>(
state: &mut BeaconState<T>,
eth1_data: &Eth1Data,
) -> Result<(), Error> {
if let Some(new_eth1_data) = get_new_eth1_data(state, eth1_data)? {
*state.eth1_data_mut() = new_eth1_data;
}
state.eth1_data_votes_mut().push(eth1_data.clone())?;
Ok(())
}
/// Returns `Ok(Some(eth1_data))` if adding the given `eth1_data` to `state.eth1_data_votes` would
/// result in a change to `state.eth1_data`.
pub fn get_new_eth1_data<T: EthSpec>(
state: &BeaconState<T>,
eth1_data: &Eth1Data,
) -> Result<Option<Eth1Data>, ArithError> {
let num_votes = state
.eth1_data_votes()
.iter()
.filter(|vote| *vote == eth1_data)
.count();
// The +1 is to account for the `eth1_data` supplied to the function.
if num_votes.safe_add(1)?.safe_mul(2)? > T::SlotsPerEth1VotingPeriod::to_usize() {
Ok(Some(eth1_data.clone()))
} else {
Ok(None)
}
}