Synclayer Batch Aggregation

l1-contracts/contracts/common/interfaces/IBatchAggregator.sol

@@ -0,0 +1,12 @@
+// SPDX-License-Identifier: MIT
+
+pragma solidity 0.8.24;
+
+interface IBatchAggregator {
+    function commitBatch(
+        bytes calldata _totalL2ToL1PubdataAndStateDiffs,
+        uint256 chainId,
+        uint256 batchNumber
+    ) external;
+    function returnBatchesAndClearState() external returns (bytes memory);
+}

l1-contracts/contracts/state-transition/chain-deps/facets/Executor.sol

@@ -11,6 +11,10 @@ import {UnsafeBytes} from "../../../common/libraries/UnsafeBytes.sol";
 import {L2_BOOTLOADER_ADDRESS, L2_TO_L1_MESSENGER_SYSTEM_CONTRACT_ADDR, L2_SYSTEM_CONTEXT_SYSTEM_CONTRACT_ADDR, L2_PUBDATA_CHUNK_PUBLISHER_ADDR} from "../../../common/L2ContractAddresses.sol";
 import {PubdataPricingMode} from "../ZkSyncHyperchainStorage.sol";
 import {IStateTransitionManager} from "../../IStateTransitionManager.sol";
+import {IBatchAggregator} from "../../../common/interfaces/IBatchAggregator.sol";
+
+// TODO: replace with actual system address
+address constant BATCH_AGGREGATOR_ADDRESS = 0x0000000000000000000000000000000000009012;
 
 // While formally the following import is not used, it is needed to inherit documentation from it
 import {IZkSyncHyperchainBase} from "../../chain-interfaces/IZkSyncHyperchainBase.sol";
@@ -32,7 +36,7 @@ contract ExecutorFacet is ZkSyncHyperchainBase, IExecutor {
         StoredBatchInfo memory _previousBatch,
         CommitBatchInfo calldata _newBatch,
         bytes32 _expectedSystemContractUpgradeTxHash
-    ) internal view returns (StoredBatchInfo memory) {
+    ) internal returns (StoredBatchInfo memory) {
         require(_newBatch.batchNumber == _previousBatch.batchNumber + 1, "f"); // only commit next batch
 
         uint8 pubdataSource = uint8(bytes1(_newBatch.pubdataCommitments[0]));
@@ -69,6 +73,14 @@ contract ExecutorFacet is ZkSyncHyperchainBase, IExecutor {
                     .pubdataCommitments
                     .length]
             );
+        } else if (pubdataSource == uint8(PubdataSource.ForwardedMessage)) {
+            // Similar to Calldata, forwards packed pubdataCommitments of hyperchains to the lower layer
+            // Add batch to BatchAggregator
+            IBatchAggregator(BATCH_AGGREGATOR_ADDRESS).commitBatch(
+                _newBatch.pubdataCommitments,
+                s.chainId,
+                _newBatch.batchNumber
+            );
         }
 
         require(_previousBatch.batchHash == logOutput.previousBatchHash, "l");

l1-contracts/contracts/state-transition/chain-interfaces/IExecutor.sol

@@ -25,7 +25,8 @@ enum SystemLogKey {
 /// @dev Enum used to determine the source of pubdata. At first we will support calldata and blobs but this can be extended.
 enum PubdataSource {
     Calldata,
-    Blob
+    Blob,
+    ForwardedMessage
 }
 
 struct LogProcessingOutput {