Gloas payload attestation consensus (#8827)

- Implement `process_payload_attestation`
- Implement EF tests for payload attestations (allows simplification of handler now that we support all `operations` tests).
- Update the `BlockSignatureVerifier` to signature-verify payload attestations


Co-Authored-By: Michael Sproul <michael@sigmaprime.io>

consensus/state_processing/src/per_block_processing/block_signature_verifier.rs

@@ -1,7 +1,9 @@
 #![allow(clippy::arithmetic_side_effects)]
 
 use super::signature_sets::{Error as SignatureSetError, *};
-use crate::per_block_processing::errors::{AttestationInvalid, BlockOperationError};
+use crate::per_block_processing::errors::{
+    AttestationInvalid, BlockOperationError, PayloadAttestationInvalid,
+};
 use crate::{ConsensusContext, ContextError};
 use bls::{PublicKey, PublicKeyBytes, SignatureSet, verify_signature_sets};
 use std::borrow::Cow;
@@ -18,6 +20,8 @@ pub enum Error {
     SignatureInvalid,
     /// An attestation in the block was invalid. The block is invalid.
     AttestationValidationError(BlockOperationError<AttestationInvalid>),
+    /// A payload attestation in the block was invalid. The block is invalid.
+    PayloadAttestationValidationError(BlockOperationError<PayloadAttestationInvalid>),
     /// There was an error attempting to read from a `BeaconState`. Block
     /// validity was not determined.
     BeaconStateError(BeaconStateError),
@@ -66,6 +70,12 @@ impl From<BlockOperationError<AttestationInvalid>> for Error {
     }
 }
 
+impl From<BlockOperationError<PayloadAttestationInvalid>> for Error {
+    fn from(e: BlockOperationError<PayloadAttestationInvalid>) -> Error {
+        Error::PayloadAttestationValidationError(e)
+    }
+}
+
 /// Reads the BLS signatures and keys from a `SignedBeaconBlock`, storing them as a `Vec<SignatureSet>`.
 ///
 /// This allows for optimizations related to batch BLS operations (see the
@@ -171,6 +181,7 @@ where
         self.include_sync_aggregate(block)?;
         self.include_bls_to_execution_changes(block)?;
         self.include_execution_payload_bid(block)?;
+        self.include_payload_attestations(block, ctxt)?;
 
         Ok(())
     }
@@ -296,6 +307,39 @@ where
             })
     }
 
+    /// Includes all signatures in `self.block.body.payload_attestations` for verification.
+    pub fn include_payload_attestations<Payload: AbstractExecPayload<E>>(
+        &mut self,
+        block: &'a SignedBeaconBlock<E, Payload>,
+        ctxt: &mut ConsensusContext<E>,
+    ) -> Result<()> {
+        let Ok(payload_attestations) = block.message().body().payload_attestations() else {
+            // Nothing to do pre-Gloas.
+            return Ok(());
+        };
+
+        self.sets.sets.reserve(payload_attestations.len());
+
+        payload_attestations
+            .iter()
+            .try_for_each(|payload_attestation| {
+                let indexed_payload_attestation = ctxt.get_indexed_payload_attestation(
+                    self.state,
+                    payload_attestation,
+                    self.spec,
+                )?;
+
+                self.sets.push(indexed_payload_attestation_signature_set(
+                    self.state,
+                    self.get_pubkey.clone(),
+                    &payload_attestation.signature,
+                    indexed_payload_attestation,
+                    self.spec,
+                )?);
+                Ok(())
+            })
+    }
+
     /// Includes all signatures in `self.block.body.voluntary_exits` for verification.
     pub fn include_exits<Payload: AbstractExecPayload<E>>(
         &mut self,

consensus/state_processing/src/per_block_processing/errors.rs

@@ -41,6 +41,10 @@ pub enum BlockProcessingError {
         index: usize,
         reason: AttestationInvalid,
     },
+    PayloadAttestationInvalid {
+        index: usize,
+        reason: PayloadAttestationInvalid,
+    },
     DepositInvalid {
         index: usize,
         reason: DepositInvalid,
@@ -217,6 +221,7 @@ impl_into_block_processing_error_with_index!(
     AttesterSlashingInvalid,
     IndexedAttestationInvalid,
     AttestationInvalid,
+    PayloadAttestationInvalid,
     DepositInvalid,
     ExitInvalid,
     BlsExecutionChangeInvalid
@@ -422,6 +427,52 @@ pub enum IndexedAttestationInvalid {
     SignatureSetError(SignatureSetError),
 }
 
+#[derive(Debug, PartialEq, Clone)]
+pub enum PayloadAttestationInvalid {
+    /// Block root does not match the parent beacon block root.
+    BlockRootMismatch {
+        expected: Hash256,
+        found: Hash256,
+    },
+    /// The attestation slot is not the previous slot.
+    SlotMismatch {
+        expected: Slot,
+        found: Slot,
+    },
+    BadIndexedPayloadAttestation(IndexedPayloadAttestationInvalid),
+}
+
+impl From<BlockOperationError<IndexedPayloadAttestationInvalid>>
+    for BlockOperationError<PayloadAttestationInvalid>
+{
+    fn from(e: BlockOperationError<IndexedPayloadAttestationInvalid>) -> Self {
+        match e {
+            BlockOperationError::Invalid(e) => BlockOperationError::invalid(
+                PayloadAttestationInvalid::BadIndexedPayloadAttestation(e),
+            ),
+            BlockOperationError::BeaconStateError(e) => BlockOperationError::BeaconStateError(e),
+            BlockOperationError::SignatureSetError(e) => BlockOperationError::SignatureSetError(e),
+            BlockOperationError::SszTypesError(e) => BlockOperationError::SszTypesError(e),
+            BlockOperationError::BitfieldError(e) => BlockOperationError::BitfieldError(e),
+            BlockOperationError::ConsensusContext(e) => BlockOperationError::ConsensusContext(e),
+            BlockOperationError::ArithError(e) => BlockOperationError::ArithError(e),
+        }
+    }
+}
+
+#[derive(Debug, PartialEq, Clone)]
+pub enum IndexedPayloadAttestationInvalid {
+    /// The number of indices is 0.
+    IndicesEmpty,
+    /// The validator indices were not in increasing order.
+    BadValidatorIndicesOrdering,
+    /// The indexed attestation aggregate signature was not valid.
+    BadSignature,
+    /// There was an error whilst attempting to get a set of signatures. The signatures may have
+    /// been invalid or an internal error occurred.
+    SignatureSetError(SignatureSetError),
+}
+
 #[derive(Debug, PartialEq, Clone)]
 pub enum DepositInvalid {
     /// The signature (proof-of-possession) does not match the given pubkey.

consensus/state_processing/src/per_block_processing/is_valid_indexed_payload_attestation.rs

@@ -0,0 +1,32 @@
+use super::errors::{BlockOperationError, IndexedPayloadAttestationInvalid as Invalid};
+use super::signature_sets::{get_pubkey_from_state, indexed_payload_attestation_signature_set};
+use crate::VerifySignatures;
+use types::*;
+
+pub fn is_valid_indexed_payload_attestation<E: EthSpec>(
+    state: &BeaconState<E>,
+    indexed_payload_attestation: &IndexedPayloadAttestation<E>,
+    verify_signatures: VerifySignatures,
+    spec: &ChainSpec,
+) -> Result<(), BlockOperationError<Invalid>> {
+    // Verify indices are non-empty and sorted (duplicates allowed)
+    let indices = &indexed_payload_attestation.attesting_indices;
+    verify!(!indices.is_empty(), Invalid::IndicesEmpty);
+    verify!(indices.is_sorted(), Invalid::BadValidatorIndicesOrdering);
+
+    if verify_signatures.is_true() {
+        verify!(
+            indexed_payload_attestation_signature_set(
+                state,
+                |i| get_pubkey_from_state(state, i),
+                &indexed_payload_attestation.signature,
+                indexed_payload_attestation,
+                spec
+            )?
+            .verify(),
+            Invalid::BadSignature
+        );
+    }
+
+    Ok(())
+}

consensus/state_processing/src/per_block_processing/process_operations.rs

@@ -5,6 +5,7 @@ use crate::common::{
     slash_validator,
 };
 use crate::per_block_processing::errors::{BlockProcessingError, IntoWithIndex};
+use crate::per_block_processing::verify_payload_attestation::verify_payload_attestation;
 use bls::{PublicKeyBytes, SignatureBytes};
 use ssz_types::FixedVector;
 use typenum::U33;
@@ -39,8 +40,15 @@ pub fn process_operations<E: EthSpec, Payload: AbstractExecPayload<E>>(
         process_bls_to_execution_changes(state, bls_to_execution_changes, verify_signatures, spec)?;
     }
 
-    if state.fork_name_unchecked().electra_enabled() && !state.fork_name_unchecked().gloas_enabled()
-    {
+    if state.fork_name_unchecked().gloas_enabled() {
+        process_payload_attestations(
+            state,
+            block_body.payload_attestations()?.iter(),
+            verify_signatures,
+            ctxt,
+            spec,
+        )?;
+    } else if state.fork_name_unchecked().electra_enabled() {
         state.update_pubkey_cache()?;
         process_deposit_requests_pre_gloas(
             state,
@@ -1074,3 +1082,45 @@ pub fn process_consolidation_request<E: EthSpec>(
 
     Ok(())
 }
+
+pub fn process_payload_attestation<E: EthSpec>(
+    state: &mut BeaconState<E>,
+    payload_attestation: &PayloadAttestation<E>,
+    att_index: usize,
+    verify_signatures: VerifySignatures,
+    ctxt: &mut ConsensusContext<E>,
+    spec: &ChainSpec,
+) -> Result<(), BlockProcessingError> {
+    verify_payload_attestation(state, payload_attestation, ctxt, verify_signatures, spec)
+        .map_err(|e| e.into_with_index(att_index))
+}
+
+pub fn process_payload_attestations<'a, E: EthSpec, I>(
+    state: &mut BeaconState<E>,
+    payload_attestations: I,
+    verify_signatures: VerifySignatures,
+    ctxt: &mut ConsensusContext<E>,
+    spec: &ChainSpec,
+) -> Result<(), BlockProcessingError>
+where
+    I: Iterator<Item = &'a PayloadAttestation<E>>,
+{
+    // Presently the PTC cache requires the committee cache for `state.slot() - 1` which is either
+    // in the current or previous epoch.
+    // TODO(gloas): These requirements may change if we introduce a PTC cache.
+    state.build_committee_cache(RelativeEpoch::Current, spec)?;
+    state.build_committee_cache(RelativeEpoch::Previous, spec)?;
+
+    payload_attestations
+        .enumerate()
+        .try_for_each(|(i, payload_attestation)| {
+            process_payload_attestation(
+                state,
+                payload_attestation,
+                i,
+                verify_signatures,
+                ctxt,
+                spec,
+            )
+        })
+}

consensus/state_processing/src/per_block_processing/signature_sets.rs

@@ -10,10 +10,10 @@ use typenum::Unsigned;
 use types::{
     AbstractExecPayload, AttesterSlashingRef, BeaconBlockRef, BeaconState, BeaconStateError,
     BuilderIndex, ChainSpec, DepositData, Domain, Epoch, EthSpec, Fork, Hash256, InconsistentFork,
-    IndexedAttestation, IndexedAttestationRef, ProposerSlashing, SignedAggregateAndProof,
-    SignedBeaconBlock, SignedBeaconBlockHeader, SignedBlsToExecutionChange,
-    SignedContributionAndProof, SignedExecutionPayloadBid, SignedRoot, SignedVoluntaryExit,
-    SigningData, Slot, SyncAggregate, SyncAggregatorSelectionData,
+    IndexedAttestation, IndexedAttestationRef, IndexedPayloadAttestation, ProposerSlashing,
+    SignedAggregateAndProof, SignedBeaconBlock, SignedBeaconBlockHeader,
+    SignedBlsToExecutionChange, SignedContributionAndProof, SignedExecutionPayloadBid, SignedRoot,
+    SignedVoluntaryExit, SigningData, Slot, SyncAggregate, SyncAggregatorSelectionData,
     consts::gloas::BUILDER_INDEX_SELF_BUILD,
 };
 
@@ -355,6 +355,40 @@ where
     Ok(SignatureSet::multiple_pubkeys(signature, pubkeys, message))
 }
 
+pub fn indexed_payload_attestation_signature_set<'a, 'b, E, F>(
+    state: &'a BeaconState<E>,
+    get_pubkey: F,
+    signature: &'a AggregateSignature,
+    indexed_payload_attestation: &'b IndexedPayloadAttestation<E>,
+    spec: &'a ChainSpec,
+) -> Result<SignatureSet<'a>>
+where
+    E: EthSpec,
+    F: Fn(usize) -> Option<Cow<'a, PublicKey>>,
+{
+    let mut pubkeys = Vec::with_capacity(indexed_payload_attestation.attesting_indices.len());
+    for &validator_idx in indexed_payload_attestation.attesting_indices.iter() {
+        pubkeys.push(
+            get_pubkey(validator_idx as usize).ok_or(Error::ValidatorUnknown(validator_idx))?,
+        );
+    }
+
+    let epoch = indexed_payload_attestation
+        .data
+        .slot
+        .epoch(E::slots_per_epoch());
+    let domain = spec.get_domain(
+        epoch,
+        Domain::PTCAttester,
+        &state.fork(),
+        state.genesis_validators_root(),
+    );
+
+    let message = indexed_payload_attestation.data.signing_root(domain);
+
+    Ok(SignatureSet::multiple_pubkeys(signature, pubkeys, message))
+}
+
 pub fn execution_payload_bid_signature_set<'a, E, F>(
     state: &'a BeaconState<E>,
     get_builder_pubkey: F,

consensus/state_processing/src/per_block_processing/verify_payload_attestation.rs

@@ -0,0 +1,46 @@
+use super::VerifySignatures;
+use super::errors::{BlockOperationError, PayloadAttestationInvalid as Invalid};
+use crate::ConsensusContext;
+use crate::per_block_processing::is_valid_indexed_payload_attestation;
+use safe_arith::SafeArith;
+use types::*;
+
+pub fn verify_payload_attestation<'ctxt, E: EthSpec>(
+    state: &mut BeaconState<E>,
+    payload_attestation: &'ctxt PayloadAttestation<E>,
+    ctxt: &'ctxt mut ConsensusContext<E>,
+    verify_signatures: VerifySignatures,
+    spec: &ChainSpec,
+) -> Result<(), BlockOperationError<Invalid>> {
+    let data = &payload_attestation.data;
+
+    // Check that the attestation is for the parent beacon block
+    verify!(
+        data.beacon_block_root == state.latest_block_header().parent_root,
+        Invalid::BlockRootMismatch {
+            expected: state.latest_block_header().parent_root,
+            found: data.beacon_block_root,
+        }
+    );
+
+    // Check that the attestation is for the previous slot
+    verify!(
+        data.slot.safe_add(1)? == state.slot(),
+        Invalid::SlotMismatch {
+            expected: state.slot().saturating_sub(Slot::new(1)),
+            found: data.slot,
+        }
+    );
+
+    let indexed_payload_attestation =
+        ctxt.get_indexed_payload_attestation(state, payload_attestation, spec)?;
+
+    is_valid_indexed_payload_attestation(
+        state,
+        indexed_payload_attestation,
+        verify_signatures,
+        spec,
+    )?;
+
+    Ok(())
+}