refactor: CallerChecker

src/bridge/AbsInbox.sol

@@ -8,19 +8,19 @@ import {
     DataTooLarge,
     Deprecated,
     GasLimitTooLarge,
-    HasCode,
     InsufficientValue,
     InsufficientSubmissionCost,
     L1Forked,
     NotAllowedOrigin,
-    NotOrigin,
+    NotTopLevel,
     NotRollupOrOwner,
     RetryableData
 } from "../libraries/Error.sol";
 import "./IInboxBase.sol";
 import "./ISequencerInbox.sol";
 import "./IBridge.sol";
 import "../libraries/AddressAliasHelper.sol";
+import "../libraries/CallerChecker.sol";
 import "../libraries/DelegateCallAware.sol";
 import {
     L1MessageType_submitRetryableTx,
@@ -142,8 +142,7 @@ abstract contract AbsInbox is DelegateCallAware, PausableUpgradeable, IInboxBase
     ) external whenNotPaused onlyAllowed returns (uint256) {
         if (_chainIdChanged()) revert L1Forked();
         // solhint-disable-next-line avoid-tx-origin
-        if (msg.sender != tx.origin) revert NotOrigin();
-        if (msg.sender.code.length != 0) revert HasCode();
+        if (!CallerChecker.isCallerTopLevel()) revert NotTopLevel();
         if (messageData.length > maxDataSize) revert DataTooLarge(messageData.length, maxDataSize);
         uint256 msgNum = _deliverToBridge(L2_MSG, msg.sender, keccak256(messageData), 0);
         emit InboxMessageDeliveredFromOrigin(msgNum);

src/bridge/SequencerInbox.sol

@@ -12,14 +12,14 @@ import {
     DelayedBackwards,
     DelayedTooFar,
     ForceIncludeBlockTooSoon,
-    HasCode,
     IncorrectMessagePreimage,
     NotBatchPoster,
     BadSequencerNumber,
     AlreadyValidDASKeyset,
     NoSuchKeyset,
     NotForked,
     NotBatchPosterManager,
+    NotTopLevel,
     RollupNotChanged,
     DataBlobsNotSupported,
     InitParamZero,
@@ -43,6 +43,7 @@ import "../rollup/IRollupLogic.sol";
 import "./Messages.sol";
 import "../precompiles/ArbGasInfo.sol";
 import "../precompiles/ArbSys.sol";
+import "../libraries/CallerChecker.sol";
 import "../libraries/IReader4844.sol";
 
 import "../libraries/DelegateCallAware.sol";
@@ -334,9 +335,7 @@ contract SequencerInbox is DelegateCallAware, GasRefundEnabled, ISequencerInbox
         uint256 prevMessageCount,
         uint256 newMessageCount
     ) external refundsGas(gasRefunder, IReader4844(address(0))) {
-        // solhint-disable-next-line avoid-tx-origin
-        if (msg.sender != tx.origin) revert NotOrigin();
-        if (msg.sender.code.length != 0) revert HasCode();
+        if (!CallerChecker.isCallerTopLevel()) revert NotTopLevel();
         if (!isBatchPoster[msg.sender]) revert NotBatchPoster();
         if (isDelayProofRequired(afterDelayedMessagesRead)) revert DelayProofRequired();
 
@@ -389,9 +388,7 @@ contract SequencerInbox is DelegateCallAware, GasRefundEnabled, ISequencerInbox
         uint256 newMessageCount,
         DelayProof calldata delayProof
     ) external refundsGas(gasRefunder, IReader4844(address(0))) {
-        // solhint-disable-next-line avoid-tx-origin
-        if (msg.sender != tx.origin) revert NotOrigin();
-        if (msg.sender.code.length != 0) revert HasCode();
+        if (!CallerChecker.isCallerTopLevel()) revert NotTopLevel();
         if (!isBatchPoster[msg.sender]) revert NotBatchPoster();
         if (!isDelayBufferable) revert NotDelayBufferable();
 
@@ -442,7 +439,7 @@ contract SequencerInbox is DelegateCallAware, GasRefundEnabled, ISequencerInbox
         // same as using calldata, we only submit spending report if the caller is the origin of the tx
         // such that one cannot "double-claim" batch posting refund in the same tx
         // solhint-disable-next-line avoid-tx-origin
-        if (msg.sender == tx.origin && msg.sender.code.length == 0 && !isUsingFeeToken) {
+        if (CallerChecker.isCallerTopLevel() && !isUsingFeeToken) {
             submitBatchSpendingReport(dataHash, seqMessageIndex, block.basefee, blobGas);
         }
     }

src/libraries/CallerChecker.sol

@@ -0,0 +1,16 @@
+// Copyright 2021-2024, Offchain Labs, Inc.
+// For license information, see https://github.com/OffchainLabs/nitro-contracts/blob/main/LICENSE
+// SPDX-License-Identifier: BUSL-1.1
+
+pragma solidity ^0.8.0;
+
+library CallerChecker {
+    /**
+     * @notice A EIP-7702 safe check for top level caller, used to ensure the calldata is available in the tx
+     * @return bool true if the caller is a top level caller, false otherwise
+     */
+    function isCallerTopLevel() internal view returns (bool) {
+        // solhint-disable-next-line avoid-tx-origin
+        return msg.sender == tx.origin && msg.sender.code.length == 0;
+    }
+}

src/libraries/Error.sol

@@ -13,8 +13,8 @@ error HadZeroInit();
 /// @dev Thrown when post upgrade init validation fails
 error BadPostUpgradeInit();
 
-/// @dev Thrown when the sender has code
-error HasCode();
+/// @dev Thrown when the caller is not a top level caller
+error NotTopLevel();
 
 /// @dev Thrown when non owner tries to access an only-owner function
 /// @param sender The msg.sender who is not the owner

src/libraries/GasRefundEnabled.sol

@@ -7,6 +7,7 @@ pragma solidity ^0.8.0;
 
 import "./IReader4844.sol";
 import "./IGasRefunder.sol";
+import "../libraries/CallerChecker.sol";
 
 abstract contract GasRefundEnabled {
     uint256 internal immutable gasPerBlob = 2 ** 17;
@@ -25,7 +26,7 @@ abstract contract GasRefundEnabled {
             // if triggered in a contract call, the spender may be overrefunded by appending dummy data to the call
             // so we check if it is a top level call, which would mean the sender paid calldata as part of tx.input
             // solhint-disable-next-line avoid-tx-origin
-            if (msg.sender != tx.origin || msg.sender.code.length != 0) {
+            if (!CallerChecker.isCallerTopLevel()) {
                 // We can't be sure if this calldata came from the top level tx,
                 // so to be safe we tell the gas refunder there was no calldata.
                 calldataSize = 0;