From 12de2cf03cfd1293591bd135da7c35f4b747520c Mon Sep 17 00:00:00 2001
From: Gavin Yu <gavin@taiko.xyz>
Date: Wed, 22 Jan 2025 20:00:27 +0800
Subject: [PATCH] feat(protocol): add `anchorV2` back (#18820)

---
 .../contracts/layer2/based/TaikoAnchor.sol    | 32 +++++++++++++++++++
 1 file changed, 32 insertions(+)

diff --git a/packages/protocol/contracts/layer2/based/TaikoAnchor.sol b/packages/protocol/contracts/layer2/based/TaikoAnchor.sol
index 205c2dc03a..4433632a87 100644
--- a/packages/protocol/contracts/layer2/based/TaikoAnchor.sol
+++ b/packages/protocol/contracts/layer2/based/TaikoAnchor.sol
@@ -172,6 +172,38 @@ contract TaikoAnchor is EssentialContract, IBlockHashProvider, TaikoAnchorDeprec
         ISignalService(resolve(LibStrings.B_SIGNAL_SERVICE, false)).receiveSignals(_signalSlots);
     }
 
+    /// @notice Anchors the latest L1 block details to L2 for cross-layer
+    /// message verification.
+    /// @dev This function can be called freely as the golden touch private key is publicly known,
+    /// but the Taiko node guarantees the first transaction of each block is always this anchor
+    /// transaction, and any subsequent calls will revert with L2_PUBLIC_INPUT_HASH_MISMATCH.
+    /// @param _anchorBlockId The `anchorBlockId` value in this block's metadata.
+    /// @param _anchorStateRoot The state root for the L1 block with id equals `_anchorBlockId`.
+    /// @param _parentGasUsed The gas used in the parent block.
+    /// @param _baseFeeConfig The base fee configuration.
+    function anchorV2(
+        uint64 _anchorBlockId,
+        bytes32 _anchorStateRoot,
+        uint32 _parentGasUsed,
+        LibSharedData.BaseFeeConfig calldata _baseFeeConfig
+    )
+        external
+        nonZeroBytes32(_anchorStateRoot)
+        nonZeroValue(_anchorBlockId)
+        nonZeroValue(_baseFeeConfig.gasIssuancePerSecond)
+        nonZeroValue(_baseFeeConfig.adjustmentQuotient)
+        onlyGoldenTouch
+        nonReentrant
+    {
+        require(block.number < pacayaForkHeight, L2_FORK_ERROR());
+
+        uint256 parentId = block.number - 1;
+        _verifyAndUpdatePublicInputHash(parentId);
+        _verifyBaseFeeAndUpdateGasExcess(_parentGasUsed, _baseFeeConfig);
+        _syncChainData(_anchorBlockId, _anchorStateRoot);
+        _updateParentHashAndTimestamp(parentId);
+    }
+
     /// @notice Withdraw token or Ether from this address.
     /// Note: This contract receives a portion of L2 base fees, while the remainder is directed to
     /// L2 block's coinbase address.