hold for now

consensus/state_processing/src/per_block_processing/signature_sets.rs

@@ -12,7 +12,7 @@ use types::{
     InconsistentFork, IndexedAttestation, IndexedAttestationRef, ProposerSlashing, PublicKey,
     PublicKeyBytes, Signature, SignedAggregateAndProof, SignedBeaconBlock, SignedBeaconBlockHeader,
     SignedBlsToExecutionChange, SignedContributionAndProof, SignedRoot, SignedVoluntaryExit,
-    SigningData, Slot, SyncAggregate, SyncAggregatorSelectionData, Unsigned,
+    SigningData, Slot, SyncAggregate, SyncAggregatorSelectionData, Unsigned, SignedExecutionPayloadEnvelope,
 };
 
 pub type Result<T> = std::result::Result<T, Error>;
@@ -331,6 +331,34 @@ where
     Ok(SignatureSet::multiple_pubkeys(signature, pubkeys, message))
 }
 
+pub fn execution_envelope_signature_set<'a, E, F>(
+    state: &'a BeaconState<E>,
+    get_pubkey: F,
+    signed_envelope: &'a SignedExecutionPayloadEnvelope<E>,
+    spec: &'a ChainSpec,
+) -> Result<SignatureSet<'a>>
+where
+    E: EthSpec,
+    F: Fn(usize) -> Option<Cow<'a, PublicKey>>,
+{
+    let domain = spec.get_domain(
+        state.current_epoch(),
+        Domain::BeaconBuilder,
+        &state.fork(),
+        state.genesis_validators_root(),
+    );
+    let message = signed_envelope.message().signing_root(domain);
+    let pubkey = get_pubkey(signed_envelope.message().builder_index() as usize).ok_or(
+        Error::ValidatorUnknown(signed_envelope.message().builder_index()),
+    )?;
+
+    Ok(SignatureSet::single_pubkey(
+        signed_envelope.signature(),
+        pubkey,
+        message,
+    ))
+}
+
 /// Returns the signature set for the given `attester_slashing` and corresponding `pubkeys`.
 pub fn attester_slashing_signature_sets<'a, E, F>(
     state: &'a BeaconState<E>,