Use attestation head state to validate attestations (#3532)

packages/lodestar/src/chain/errors/attestationError.ts

@@ -118,9 +118,9 @@ export enum AttestationErrorCode {
    */
   COMMITTEE_INDEX_OUT_OF_RANGE = "ATTESTATION_ERROR_COMMITTEE_INDEX_OUT_OF_RANGE",
   /**
-   * Missing attestation pre-state.
+   * Missing attestation head state
    */
-  MISSING_ATTESTATION_TARGET_STATE = "ATTESTATION_ERROR_MISSING_ATTESTATION_TARGET_STATE",
+  MISSING_ATTESTATION_HEAD_STATE = "ATTESTATION_ERROR_MISSING_ATTESTATION_HEAD_STATE",
   /**
    * Invalid aggregator.
    */
@@ -160,7 +160,7 @@ export type AttestationErrorType =
   | {code: AttestationErrorCode.INVALID_TARGET_ROOT; targetRoot: RootHex; expected: string | null}
   | {code: AttestationErrorCode.TARGET_BLOCK_NOT_AN_ANCESTOR_OF_LMD_BLOCK}
   | {code: AttestationErrorCode.COMMITTEE_INDEX_OUT_OF_RANGE; index: number}
-  | {code: AttestationErrorCode.MISSING_ATTESTATION_TARGET_STATE; error: Error}
+  | {code: AttestationErrorCode.MISSING_ATTESTATION_HEAD_STATE; error: Error}
   | {code: AttestationErrorCode.INVALID_AGGREGATOR}
   | {code: AttestationErrorCode.INVALID_INDEXED_ATTESTATION};
 

packages/lodestar/src/chain/validation/aggregateAndProof.ts

@@ -55,22 +55,22 @@ export async function validateGossipAggregateAndProof(
 
   // [IGNORE] The block being voted for (attestation.data.beacon_block_root) has been seen (via both gossip
   // and non-gossip sources) (a client MAY queue attestations for processing once block is retrieved).
-  verifyHeadBlockAndTargetRoot(chain, attData.beaconBlockRoot, attTarget.root, attEpoch);
+  const attHeadBlock = verifyHeadBlockAndTargetRoot(chain, attData.beaconBlockRoot, attTarget.root, attEpoch);
 
   // [REJECT] The current finalized_checkpoint is an ancestor of the block defined by aggregate.data.beacon_block_root
   // -- i.e. get_ancestor(store, aggregate.data.beacon_block_root, compute_start_slot_at_epoch(store.finalized_checkpoint.epoch)) == store.finalized_checkpoint.root
   // > Altready check in `chain.forkChoice.hasBlock(attestation.data.beaconBlockRoot)`
 
-  const targetState = await chain.regen
-    .getCheckpointState(attTarget, RegenCaller.validateGossipAggregateAndProof)
+  const attHeadState = await chain.regen
+    .getState(attHeadBlock.stateRoot, RegenCaller.validateGossipAggregateAndProof)
     .catch((e: Error) => {
       throw new AttestationError(GossipAction.REJECT, {
-        code: AttestationErrorCode.MISSING_ATTESTATION_TARGET_STATE,
+        code: AttestationErrorCode.MISSING_ATTESTATION_HEAD_STATE,
         error: e as Error,
       });
     });
 
-  const committeeIndices = getCommitteeIndices(targetState, attSlot, attData.index);
+  const committeeIndices = getCommitteeIndices(attHeadState, attSlot, attData.index);
   const attestingIndices = zipIndexesCommitteeBits(committeeIndices, aggregate.aggregationBits);
   const indexedAttestation: phase0.IndexedAttestation = {
     attestingIndices: attestingIndices as List<number>,
@@ -102,11 +102,11 @@ export async function validateGossipAggregateAndProof(
   // by the validator with index aggregate_and_proof.aggregator_index.
   // [REJECT] The aggregator signature, signed_aggregate_and_proof.signature, is valid.
   // [REJECT] The signature of aggregate is valid.
-  const aggregator = targetState.index2pubkey[aggregateAndProof.aggregatorIndex];
+  const aggregator = attHeadState.index2pubkey[aggregateAndProof.aggregatorIndex];
   const signatureSets = [
-    getSelectionProofSignatureSet(targetState, attSlot, aggregator, signedAggregateAndProof),
-    getAggregateAndProofSignatureSet(targetState, attEpoch, aggregator, signedAggregateAndProof),
-    allForks.getIndexedAttestationSignatureSet(targetState, indexedAttestation),
+    getSelectionProofSignatureSet(attHeadState, attSlot, aggregator, signedAggregateAndProof),
+    getAggregateAndProofSignatureSet(attHeadState, attEpoch, aggregator, signedAggregateAndProof),
+    allForks.getIndexedAttestationSignatureSet(attHeadState, indexedAttestation),
   ];
   if (!(await chain.bls.verifySignatureSets(signatureSets, {batchable: true}))) {
     throw new AttestationError(GossipAction.REJECT, {code: AttestationErrorCode.INVALID_SIGNATURE});

packages/lodestar/src/chain/validation/attestation.ts

@@ -72,7 +72,7 @@ export async function validateGossipAttestation(
 
   // [IGNORE] The block being voted for (attestation.data.beacon_block_root) has been seen (via both gossip
   // and non-gossip sources) (a client MAY queue attestations for processing once block is retrieved).
-  verifyHeadBlockAndTargetRoot(chain, attData.beaconBlockRoot, attTarget.root, attEpoch);
+  const attHeadBlock = verifyHeadBlockAndTargetRoot(chain, attData.beaconBlockRoot, attTarget.root, attEpoch);
 
   // [REJECT] The block being voted for (attestation.data.beacon_block_root) passes validation.
   // > Altready check in `verifyHeadBlockAndTargetRoot()`
@@ -85,19 +85,19 @@ export async function validateGossipAttestation(
   //  --i.e. get_ancestor(store, attestation.data.beacon_block_root, compute_start_slot_at_epoch(attestation.data.target.epoch)) == attestation.data.target.root
   // > Altready check in `verifyHeadBlockAndTargetRoot()`
 
-  const attestationTargetState = await chain.regen
-    .getCheckpointState(attTarget, RegenCaller.validateGossipAttestation)
+  const attHeadState = await chain.regen
+    .getState(attHeadBlock.stateRoot, RegenCaller.validateGossipAttestation)
     .catch((e: Error) => {
       throw new AttestationError(GossipAction.REJECT, {
-        code: AttestationErrorCode.MISSING_ATTESTATION_TARGET_STATE,
+        code: AttestationErrorCode.MISSING_ATTESTATION_HEAD_STATE,
         error: e as Error,
       });
     });
 
   // [REJECT] The committee index is within the expected range
   // -- i.e. data.index < get_committee_count_per_slot(state, data.target.epoch)
   const attIndex = attData.index;
-  const committeeIndices = getCommitteeIndices(attestationTargetState, attSlot, attIndex);
+  const committeeIndices = getCommitteeIndices(attHeadState, attSlot, attIndex);
   const validatorIndex = committeeIndices[bitIndex];
 
   // [REJECT] The number of aggregation bits matches the committee size
@@ -116,7 +116,7 @@ export async function validateGossipAttestation(
   // -- i.e. compute_subnet_for_attestation(committees_per_slot, attestation.data.slot, attestation.data.index) == subnet_id,
   // where committees_per_slot = get_committee_count_per_slot(state, attestation.data.target.epoch),
   // which may be pre-computed along with the committee information for the signature check.
-  const expectedSubnet = computeSubnetForSlot(attestationTargetState, attSlot, attIndex);
+  const expectedSubnet = computeSubnetForSlot(attHeadState, attSlot, attIndex);
   if (subnet !== null && subnet !== expectedSubnet) {
     throw new AttestationError(GossipAction.REJECT, {
       code: AttestationErrorCode.INVALID_SUBNET_ID,
@@ -141,7 +141,7 @@ export async function validateGossipAttestation(
     data: attData,
     signature: attestation.signature,
   };
-  const signatureSet = getIndexedAttestationSignatureSet(attestationTargetState, indexedAttestation);
+  const signatureSet = getIndexedAttestationSignatureSet(attHeadState, indexedAttestation);
   if (!(await chain.bls.verifySignatureSets([signatureSet], {batchable: true}))) {
     throw new AttestationError(GossipAction.REJECT, {code: AttestationErrorCode.INVALID_SIGNATURE});
   }
@@ -206,9 +206,10 @@ export function verifyHeadBlockAndTargetRoot(
   beaconBlockRoot: Root,
   targetRoot: Root,
   attestationEpoch: Epoch
-): void {
+): IProtoBlock {
   const headBlock = verifyHeadBlockIsKnown(chain, beaconBlockRoot);
   verifyAttestationTargetRoot(headBlock, targetRoot, attestationEpoch);
+  return headBlock;
 }
 
 /**

packages/lodestar/test/utils/validationData/attestation.ts

@@ -107,7 +107,7 @@ export function getAttestationValidData(
 
   // Add state to regen
   const regen = ({
-    getCheckpointState: async () => (state as unknown) as CachedBeaconState<allForks.BeaconState>,
+    getState: async () => (state as unknown) as CachedBeaconState<allForks.BeaconState>,
   } as Partial<IStateRegenerator>) as IStateRegenerator;
 
   const chain = ({