EIP-4844: Update state transition function

packages/state-transition/src/block/index.ts

@@ -1,5 +1,5 @@
 import {ForkSeq} from "@lodestar/params";
-import {allForks, altair, capella} from "@lodestar/types";
+import {allForks, altair, capella, eip4844} from "@lodestar/types";
 import {getFullOrBlindedPayload, isExecutionEnabled} from "../util/execution.js";
 import {CachedBeaconStateAllForks, CachedBeaconStateCapella, CachedBeaconStateBellatrix} from "../types.js";
 import {processExecutionPayload} from "./processExecutionPayload.js";
@@ -8,7 +8,8 @@ import {processBlockHeader} from "./processBlockHeader.js";
 import {processEth1Data} from "./processEth1Data.js";
 import {processOperations} from "./processOperations.js";
 import {processRandao} from "./processRandao.js";
-import {BlockExternalData} from "./externalData.js";
+import {processBlobKzgCommitments} from "./processBlobKzgCommitments.js";
+import {BlockExternalData, DataAvailableStatus} from "./externalData.js";
 import {processWithdrawals} from "./processWithdrawals.js";
 
 // Spec tests
@@ -46,7 +47,9 @@ export function processBlock(
   // on the randao_mix computed with the reveal of the previous block.
   if (fork >= ForkSeq.bellatrix && isExecutionEnabled(state as CachedBeaconStateBellatrix, block)) {
     const fullOrBlindedPayload = getFullOrBlindedPayload(block);
-    if (fork >= ForkSeq.capella) {
+    // TODO EIP-4844: Allow to disable withdrawals for interop testing
+    // https://github.com/ethereum/consensus-specs/blob/b62c9e877990242d63aa17a2a59a49bc649a2f2e/specs/eip4844/beacon-chain.md#disabling-withdrawals
+    if (fork >= ForkSeq.capella && !opts?.disabledWithdrawals) {
       processWithdrawals(
         state as CachedBeaconStateCapella,
         fullOrBlindedPayload as capella.FullOrBlindedExecutionPayload
@@ -61,4 +64,21 @@ export function processBlock(
   if (fork >= ForkSeq.altair) {
     processSyncAggregate(state, block as altair.BeaconBlock, verifySignatures);
   }
+
+  if (fork >= ForkSeq.eip4844) {
+    processBlobKzgCommitments(block.body as eip4844.BeaconBlockBody);
+
+    // New in EIP-4844, note: Can sync optimistically without this condition, see note on `is_data_available`
+    // NOTE: Ommitted and should be verified beforehand
+
+    // assert is_data_available(block.slot, hash_tree_root(block), block.body.blob_kzg_commitments)
+    switch (externalData.dataAvailableStatus) {
+      case DataAvailableStatus.preEIP4844:
+        throw Error("dataAvailableStatus preEIP4844");
+      case DataAvailableStatus.notAvailable:
+        throw Error("dataAvailableStatus notAvailable");
+      case DataAvailableStatus.available:
+        break; // ok
+    }
+  }
 }

packages/state-transition/src/block/processBlobKzgCommitments.ts

@@ -0,0 +1,17 @@
+import {eip4844} from "@lodestar/types";
+import {verifyKzgCommitmentsAgainstTransactions} from "../util/index.js";
+
+/**
+ * https://github.com/ethereum/consensus-specs/blob/11a037fd9227e29ee809c9397b09f8cc3383a8c0/specs/eip4844/beacon-chain.md#blob-kzg-commitments
+ *
+ * def process_blob_kzg_commitments(state: BeaconState, body: BeaconBlockBody):
+ *   assert verify_kzg_commitments_against_transactions(
+ *     body.execution_payload.transactions,
+ *     body.blob_kzg_commitments
+ *   )
+ */
+export function processBlobKzgCommitments(body: eip4844.BeaconBlockBody): void {
+  if (!verifyKzgCommitmentsAgainstTransactions(body.executionPayload.transactions, body.blobKzgCommitments)) {
+    throw Error("Invalid KZG commitments against transactions");
+  }
+}

packages/state-transition/src/block/processExecutionPayload.ts

@@ -1,4 +1,4 @@
-import {ssz, allForks, capella} from "@lodestar/types";
+import {ssz, allForks, capella, eip4844} from "@lodestar/types";
 import {toHexString, byteArrayEquals} from "@chainsafe/ssz";
 import {ForkSeq} from "@lodestar/params";
 import {CachedBeaconStateBellatrix, CachedBeaconStateCapella} from "../types.js";
@@ -89,6 +89,13 @@ export function processExecutionPayload(
     );
   }
 
+  if (fork >= ForkSeq.eip4844) {
+    // https://github.com/ethereum/consensus-specs/blob/dev/specs/eip4844/beacon-chain.md#process_execution_payload
+    (bellatrixPayloadFields as eip4844.ExecutionPayloadHeader).excessDataGas = (payload as
+      | eip4844.ExecutionPayloadHeader
+      | eip4844.ExecutionPayload).excessDataGas;
+  }
+
   // TODO EIP-4844: Types are not happy by default. Since it's a generic allForks type going through ViewDU
   // transformation then into allForks, probably some weird intersection incompatibility happens
   state.latestExecutionPayloadHeader = state.config

packages/state-transition/src/cache/types.ts

@@ -11,11 +11,12 @@ export type BeaconStateEip4844 = CompositeViewDU<typeof ssz.eip4844.BeaconState>
 // - Works well as function argument and as generic type for allForks functions
 //
 // Quasy equivalent to
-// CompositeViewDU<typeof ssz.phase0.BeaconState | typeof ssz.altair.BeaconState | typeof ssz.bellatrix.BeaconState>
+// CompositeViewDU<typeof ssz.phase0.BeaconState | typeof ssz.altair.BeaconState | ...> // + future forks
 export type BeaconStateAllForks =
   | BeaconStatePhase0
   | BeaconStateAltair
   | BeaconStateBellatrix
   | BeaconStateCapella
   | BeaconStateEip4844;
+
 export type BeaconStateExecutions = BeaconStateBellatrix | BeaconStateCapella | BeaconStateEip4844;

packages/state-transition/src/slot/index.ts

@@ -6,6 +6,7 @@ import {ZERO_HASH} from "../constants/index.js";
 export {upgradeStateToAltair} from "./upgradeStateToAltair.js";
 export {upgradeStateToBellatrix} from "./upgradeStateToBellatrix.js";
 export {upgradeStateToCapella} from "./upgradeStateToCapella.js";
+export {upgradeStateTo4844} from "./upgradeStateTo4844.js";
 
 /**
  * Dial state to next slot. Common for all forks

packages/state-transition/src/slot/upgradeStateTo4844.ts

@@ -0,0 +1,33 @@
+import {ssz} from "@lodestar/types";
+import {CachedBeaconStateEip4844} from "../types.js";
+import {getCachedBeaconState} from "../cache/stateCache.js";
+import {CachedBeaconStateCapella} from "../types.js";
+
+/**
+ * Upgrade a state from Capella to 4844.
+ */
+export function upgradeStateTo4844(stateCapella: CachedBeaconStateCapella): CachedBeaconStateEip4844 {
+  const {config} = stateCapella;
+
+  const stateCapellaNode = ssz.capella.BeaconState.commitViewDU(stateCapella);
+  const state4844View = ssz.eip4844.BeaconState.getViewDU(stateCapellaNode);
+
+  const state4844 = getCachedBeaconState(state4844View, stateCapella);
+
+  state4844.fork = ssz.phase0.Fork.toViewDU({
+    previousVersion: stateCapella.fork.currentVersion,
+    currentVersion: config.EIP4844_FORK_VERSION,
+    epoch: stateCapella.epochCtx.epoch,
+  });
+
+  // capella.latestExecutionPayloadHeader has 15 properties, adding only 1 extra will not increase the tree depth.
+  // The initial value of the new property 'excessDataGas' is zero, so the default tree value is correct.
+  // Just casting the same tree node to state4844 is sufficient and nothing has to be done.
+  // ```
+  // state4844.latestExecutionPayloadHeader.excessDataGas = ssz.UintBn256.defaultValue()
+  // ```
+
+  state4844.commit();
+
+  return state4844;
+}

packages/state-transition/src/slot/upgradeStateToCapella.ts

@@ -3,7 +3,7 @@ import {CachedBeaconStateBellatrix, CachedBeaconStateCapella} from "../types.js"
 import {getCachedBeaconState} from "../cache/stateCache.js";
 
 /**
- * Upgrade a state from altair to bellatrix.
+ * Upgrade a state from bellatrix to capella.
  */
 export function upgradeStateToCapella(stateBellatrix: CachedBeaconStateBellatrix): CachedBeaconStateCapella {
   const {config} = stateBellatrix;

packages/state-transition/src/stateTransition.ts

@@ -9,10 +9,17 @@ import {
   CachedBeaconStatePhase0,
   CachedBeaconStateAltair,
   CachedBeaconStateBellatrix,
+  CachedBeaconStateCapella,
 } from "./types.js";
 import {computeEpochAtSlot} from "./util/index.js";
 import {verifyProposerSignature} from "./signatureSets/index.js";
-import {processSlot, upgradeStateToAltair, upgradeStateToBellatrix, upgradeStateToCapella} from "./slot/index.js";
+import {
+  processSlot,
+  upgradeStateToAltair,
+  upgradeStateToBellatrix,
+  upgradeStateToCapella,
+  upgradeStateTo4844,
+} from "./slot/index.js";
 import {processBlock} from "./block/index.js";
 import {processEpoch} from "./epoch/index.js";
 import {BlockExternalData, DataAvailableStatus, ExecutionPayloadStatus} from "./block/externalData.js";
@@ -168,6 +175,9 @@ function processSlotsWithTransientCache(
       if (stateSlot === config.CAPELLA_FORK_EPOCH) {
         postState = upgradeStateToCapella(postState as CachedBeaconStateBellatrix) as CachedBeaconStateAllForks;
       }
+      if (stateSlot === config.EIP4844_FORK_EPOCH) {
+        postState = upgradeStateTo4844(postState as CachedBeaconStateCapella) as CachedBeaconStateAllForks;
+      }
     } else {
       postState.slot++;
     }