Add normalizeMerkleBranch

packages/beacon-node/src/chain/lightClient/proofs.ts

@@ -1,6 +1,11 @@
 import {Tree} from "@chainsafe/persistent-merkle-tree";
 import {BeaconStateAllForks, CachedBeaconStateAllForks} from "@lodestar/state-transition";
-import {FINALIZED_ROOT_GINDEX, BLOCK_BODY_EXECUTION_PAYLOAD_GINDEX, ForkExecution, FINALIZED_ROOT_GINDEX_ELECTRA} from "@lodestar/params";
+import {
+  FINALIZED_ROOT_GINDEX,
+  BLOCK_BODY_EXECUTION_PAYLOAD_GINDEX,
+  ForkExecution,
+  FINALIZED_ROOT_GINDEX_ELECTRA,
+} from "@lodestar/params";
 import {BeaconBlockBody, SSZTypesFor, ssz} from "@lodestar/types";
 
 import {SyncCommitteeWitness} from "./types.js";

packages/beacon-node/src/network/reqresp/types.ts

@@ -1,7 +1,20 @@
 import {Type} from "@chainsafe/ssz";
 import {ForkLightClient, ForkName, isForkLightClient} from "@lodestar/params";
 import {Protocol, ProtocolHandler, ReqRespRequest} from "@lodestar/reqresp";
-import {Metadata, Root, SignedBeaconBlock, altair, deneb, phase0, ssz, sszTypesFor} from "@lodestar/types";
+import {
+  LightClientBootstrap,
+  LightClientFinalityUpdate,
+  LightClientOptimisticUpdate,
+  LightClientUpdate,
+  Metadata,
+  Root,
+  SignedBeaconBlock,
+  altair,
+  deneb,
+  phase0,
+  ssz,
+  sszTypesFor,
+} from "@lodestar/types";
 
 export type ProtocolNoHandler = Omit<Protocol, "handler">;
 
@@ -48,10 +61,10 @@ type ResponseBodyByMethod = {
   [ReqRespMethod.BeaconBlocksByRoot]: SignedBeaconBlock;
   [ReqRespMethod.BlobSidecarsByRange]: deneb.BlobSidecar;
   [ReqRespMethod.BlobSidecarsByRoot]: deneb.BlobSidecar;
-  [ReqRespMethod.LightClientBootstrap]: altair.LightClientBootstrap;
-  [ReqRespMethod.LightClientUpdatesByRange]: altair.LightClientUpdate;
-  [ReqRespMethod.LightClientFinalityUpdate]: altair.LightClientFinalityUpdate;
-  [ReqRespMethod.LightClientOptimisticUpdate]: altair.LightClientOptimisticUpdate;
+  [ReqRespMethod.LightClientBootstrap]: LightClientBootstrap;
+  [ReqRespMethod.LightClientUpdatesByRange]: LightClientUpdate;
+  [ReqRespMethod.LightClientFinalityUpdate]: LightClientFinalityUpdate;
+  [ReqRespMethod.LightClientOptimisticUpdate]: LightClientOptimisticUpdate;
 };
 
 /** Request SSZ type for each method and ForkName */

packages/light-client/src/spec/utils.ts

@@ -9,6 +9,7 @@ import {
   BLOCK_BODY_EXECUTION_PAYLOAD_INDEX as EXECUTION_PAYLOAD_INDEX,
   NEXT_SYNC_COMMITTEE_DEPTH_ELECTRA,
   isForkPostElectra,
+  FINALIZED_ROOT_DEPTH_ELECTRA,
 } from "@lodestar/params";
 import {
   ssz,
@@ -24,6 +25,7 @@ import {
 import {ChainForkConfig} from "@lodestar/config";
 
 import {isValidMerkleBranch, computeEpochAtSlot, computeSyncPeriodAtSlot} from "../utils/index.js";
+import {normalizeMerkleBranch} from "../utils/normalizeMerkleBranch.js";
 import {LightClientStore} from "./store.js";
 
 export const GENESIS_SLOT = 0;
@@ -44,15 +46,18 @@ export function getSafetyThreshold(maxActiveParticipants: number): number {
 }
 
 export function getZeroSyncCommitteeBranch(fork: ForkName): Uint8Array[] {
-  const nextSyncCommitteeDepth = isForkPostElectra(fork) ? NEXT_SYNC_COMMITTEE_DEPTH_ELECTRA : NEXT_SYNC_COMMITTEE_DEPTH;
+  const nextSyncCommitteeDepth = isForkPostElectra(fork)
+    ? NEXT_SYNC_COMMITTEE_DEPTH_ELECTRA
+    : NEXT_SYNC_COMMITTEE_DEPTH;
 
   return Array.from({length: nextSyncCommitteeDepth}, () => ZERO_HASH);
 }
 
 export function isSyncCommitteeUpdate(update: LightClientUpdate): boolean {
   return (
     // Fast return for when constructing full LightClientUpdate from partial updates
-    update.nextSyncCommitteeBranch !== getZeroSyncCommitteeBranch(isElectraLightClientUpdate(update) ? ForkName.electra : ForkName.altair) &&
+    update.nextSyncCommitteeBranch !==
+      getZeroSyncCommitteeBranch(isElectraLightClientUpdate(update) ? ForkName.electra : ForkName.altair) &&
     update.nextSyncCommitteeBranch.some((branch) => !byteArrayEquals(branch, ZERO_HASH))
   );
 }
@@ -169,7 +174,7 @@ export function isValidLightClientHeader(config: ChainForkConfig, header: LightC
     if (
       (header as LightClientHeader<ForkName.electra>).execution.depositRequestsRoot !== undefined ||
       (header as LightClientHeader<ForkName.electra>).execution.withdrawalRequestsRoot !== undefined ||
-      (header as LightClientHeader<ForkName.electra>).execution.consolidationRequestsRoot !== undefined 
+      (header as LightClientHeader<ForkName.electra>).execution.consolidationRequestsRoot !== undefined
     ) {
       return false;
     }
@@ -193,6 +198,14 @@ export function upgradeLightClientUpdate(
 ): LightClientUpdate {
   update.attestedHeader = upgradeLightClientHeader(config, targetFork, update.attestedHeader);
   update.finalizedHeader = upgradeLightClientHeader(config, targetFork, update.finalizedHeader);
+  update.nextSyncCommitteeBranch = normalizeMerkleBranch(
+    update.nextSyncCommitteeBranch,
+    isForkPostElectra(targetFork) ? NEXT_SYNC_COMMITTEE_DEPTH_ELECTRA : NEXT_SYNC_COMMITTEE_DEPTH
+  );
+  update.finalityBranch = normalizeMerkleBranch(
+    update.finalityBranch,
+    isForkPostElectra(targetFork) ? FINALIZED_ROOT_DEPTH_ELECTRA : FINALIZED_ROOT_DEPTH
+  );
 
   return update;
 }
@@ -204,6 +217,10 @@ export function upgradeLightClientFinalityUpdate(
 ): LightClientFinalityUpdate {
   finalityUpdate.attestedHeader = upgradeLightClientHeader(config, targetFork, finalityUpdate.attestedHeader);
   finalityUpdate.finalizedHeader = upgradeLightClientHeader(config, targetFork, finalityUpdate.finalizedHeader);
+  finalityUpdate.finalityBranch = normalizeMerkleBranch(
+    finalityUpdate.finalityBranch,
+    isForkPostElectra(targetFork) ? FINALIZED_ROOT_DEPTH_ELECTRA : FINALIZED_ROOT_DEPTH
+  );
 
   return finalityUpdate;
 }

packages/light-client/src/spec/validateLightClientBootstrap.ts

@@ -2,9 +2,9 @@ import {byteArrayEquals} from "@chainsafe/ssz";
 import {LightClientBootstrap, Root, ssz} from "@lodestar/types";
 import {ChainForkConfig} from "@lodestar/config";
 import {toHex} from "@lodestar/utils";
+import {isForkPostElectra} from "@lodestar/params";
 import {isValidMerkleBranch} from "../utils/verifyMerkleBranch.js";
 import {isValidLightClientHeader} from "./utils.js";
-import { isForkPostElectra } from "@lodestar/params";
 
 const CURRENT_SYNC_COMMITTEE_INDEX = 22;
 const CURRENT_SYNC_COMMITTEE_DEPTH = 5;

packages/light-client/src/spec/validateLightClientUpdate.ts

@@ -5,7 +5,6 @@ import {ChainForkConfig} from "@lodestar/config";
 import {
   FINALIZED_ROOT_INDEX,
   FINALIZED_ROOT_DEPTH,
-  NEXT_SYNC_COMMITTEE_INDEX,
   NEXT_SYNC_COMMITTEE_DEPTH,
   MIN_SYNC_COMMITTEE_PARTICIPANTS,
   DOMAIN_SYNC_COMMITTEE,

packages/light-client/src/utils/normalizeMerkleBranch.ts

@@ -0,0 +1,16 @@
+import {ZERO_HASH} from "../spec/utils.js";
+
+export const SYNC_COMMITTEES_DEPTH = 4;
+export const SYNC_COMMITTEES_INDEX = 11;
+
+/**
+ * Given merkle branch ``branch``, extend its depth according to ``depth``
+ * If given ``depth`` is less than the depth of ``branch``, it will return
+ * unmodified ``branch``
+ */
+export function normalizeMerkleBranch(branch: Uint8Array[], depth: number): Uint8Array[] {
+  const numBytes = Math.floor(branch.length / 8);
+  const numExtraBytesRequired = depth - numBytes;
+
+  return [...Array.from({length: numExtraBytesRequired}, () => ZERO_HASH), ...branch];
+}

packages/light-client/src/validation.ts

@@ -1,6 +1,14 @@
 import bls from "@chainsafe/bls";
 import type {PublicKey, Signature} from "@chainsafe/bls/types";
-import {altair, isElectraLightClientUpdate, LightClientFinalityUpdate, LightClientUpdate, Root, Slot, ssz} from "@lodestar/types";
+import {
+  altair,
+  isElectraLightClientUpdate,
+  LightClientFinalityUpdate,
+  LightClientUpdate,
+  Root,
+  Slot,
+  ssz,
+} from "@lodestar/types";
 import {
   FINALIZED_ROOT_INDEX,
   FINALIZED_ROOT_DEPTH,
@@ -42,7 +50,11 @@ export function assertValidLightClientUpdate(
   if (isFinalized) {
     assertValidFinalityProof(update);
   } else {
-    assertZeroHashes(update.finalityBranch, isElectraLightClientUpdate(update) ? FINALIZED_ROOT_DEPTH_ELECTRA : FINALIZED_ROOT_DEPTH, "finalityBranches");
+    assertZeroHashes(
+      update.finalityBranch,
+      isElectraLightClientUpdate(update) ? FINALIZED_ROOT_DEPTH_ELECTRA : FINALIZED_ROOT_DEPTH,
+      "finalityBranches"
+    );
   }
 
   // DIFF FROM SPEC: