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/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,