Contract Name:
PolygonMessengerWrapper
Contract Source Code:
// SPDX-License-Identifier: MIT
pragma solidity >=0.6.12 <=0.8.9;
pragma experimental ABIEncoderV2;
interface IMessengerWrapper {
function sendCrossDomainMessage(bytes memory _calldata) external;
function verifySender(address l1BridgeCaller, bytes memory _data) external;
function confirmRoots(
bytes32[] calldata rootHashes,
uint256[] calldata destinationChainIds,
uint256[] calldata totalAmounts,
uint256[] calldata rootCommittedAts
) external;
}
pragma solidity ^0.8.0;
import {RLPReader} from "./RLPReader.sol";
library ExitPayloadReader {
using RLPReader for bytes;
using RLPReader for RLPReader.RLPItem;
uint8 constant WORD_SIZE = 32;
struct ExitPayload {
RLPReader.RLPItem[] data;
}
struct Receipt {
RLPReader.RLPItem[] data;
bytes raw;
uint256 logIndex;
}
struct Log {
RLPReader.RLPItem data;
RLPReader.RLPItem[] list;
}
struct LogTopics {
RLPReader.RLPItem[] data;
}
// copy paste of private copy() from RLPReader to avoid changing of existing contracts
function copy(
uint256 src,
uint256 dest,
uint256 len
) private pure {
if (len == 0) return;
// copy as many word sizes as possible
for (; len >= WORD_SIZE; len -= WORD_SIZE) {
assembly {
mstore(dest, mload(src))
}
src += WORD_SIZE;
dest += WORD_SIZE;
}
// left over bytes. Mask is used to remove unwanted bytes from the word
uint256 mask = 256**(WORD_SIZE - len) - 1;
assembly {
let srcpart := and(mload(src), not(mask)) // zero out src
let destpart := and(mload(dest), mask) // retrieve the bytes
mstore(dest, or(destpart, srcpart))
}
}
function toExitPayload(bytes memory data) internal pure returns (ExitPayload memory) {
RLPReader.RLPItem[] memory payloadData = data.toRlpItem().toList();
return ExitPayload(payloadData);
}
function getHeaderNumber(ExitPayload memory payload) internal pure returns (uint256) {
return payload.data[0].toUint();
}
function getBlockProof(ExitPayload memory payload) internal pure returns (bytes memory) {
return payload.data[1].toBytes();
}
function getBlockNumber(ExitPayload memory payload) internal pure returns (uint256) {
return payload.data[2].toUint();
}
function getBlockTime(ExitPayload memory payload) internal pure returns (uint256) {
return payload.data[3].toUint();
}
function getTxRoot(ExitPayload memory payload) internal pure returns (bytes32) {
return bytes32(payload.data[4].toUint());
}
function getReceiptRoot(ExitPayload memory payload) internal pure returns (bytes32) {
return bytes32(payload.data[5].toUint());
}
function getReceipt(ExitPayload memory payload) internal pure returns (Receipt memory receipt) {
receipt.raw = payload.data[6].toBytes();
RLPReader.RLPItem memory receiptItem = receipt.raw.toRlpItem();
if (receiptItem.isList()) {
// legacy tx
receipt.data = receiptItem.toList();
} else {
// pop first byte before parsting receipt
bytes memory typedBytes = receipt.raw;
bytes memory result = new bytes(typedBytes.length - 1);
uint256 srcPtr;
uint256 destPtr;
assembly {
srcPtr := add(33, typedBytes)
destPtr := add(0x20, result)
}
copy(srcPtr, destPtr, result.length);
receipt.data = result.toRlpItem().toList();
}
receipt.logIndex = getReceiptLogIndex(payload);
return receipt;
}
function getReceiptProof(ExitPayload memory payload) internal pure returns (bytes memory) {
return payload.data[7].toBytes();
}
function getBranchMaskAsBytes(ExitPayload memory payload) internal pure returns (bytes memory) {
return payload.data[8].toBytes();
}
function getBranchMaskAsUint(ExitPayload memory payload) internal pure returns (uint256) {
return payload.data[8].toUint();
}
function getReceiptLogIndex(ExitPayload memory payload) internal pure returns (uint256) {
return payload.data[9].toUint();
}
// Receipt methods
function toBytes(Receipt memory receipt) internal pure returns (bytes memory) {
return receipt.raw;
}
function getLog(Receipt memory receipt) internal pure returns (Log memory) {
RLPReader.RLPItem memory logData = receipt.data[3].toList()[receipt.logIndex];
return Log(logData, logData.toList());
}
// Log methods
function getEmitter(Log memory log) internal pure returns (address) {
return RLPReader.toAddress(log.list[0]);
}
function getTopics(Log memory log) internal pure returns (LogTopics memory) {
return LogTopics(log.list[1].toList());
}
function getData(Log memory log) internal pure returns (bytes memory) {
return log.list[2].toBytes();
}
function toRlpBytes(Log memory log) internal pure returns (bytes memory) {
return log.data.toRlpBytes();
}
// LogTopics methods
function getField(LogTopics memory topics, uint256 index) internal pure returns (RLPReader.RLPItem memory) {
return topics.data[index];
}
}
// SPDX-License-Identifier: MIT
pragma solidity ^0.8.0;
library Merkle {
function checkMembership(
bytes32 leaf,
uint256 index,
bytes32 rootHash,
bytes memory proof
) internal pure returns (bool) {
require(proof.length % 32 == 0, "Invalid proof length");
uint256 proofHeight = proof.length / 32;
// Proof of size n means, height of the tree is n+1.
// In a tree of height n+1, max #leafs possible is 2 ^ n
require(index < 2**proofHeight, "Leaf index is too big");
bytes32 proofElement;
bytes32 computedHash = leaf;
for (uint256 i = 32; i <= proof.length; i += 32) {
assembly {
proofElement := mload(add(proof, i))
}
if (index % 2 == 0) {
computedHash = keccak256(abi.encodePacked(computedHash, proofElement));
} else {
computedHash = keccak256(abi.encodePacked(proofElement, computedHash));
}
index = index / 2;
}
return computedHash == rootHash;
}
}
// SPDX-License-Identifier: MIT
pragma solidity ^0.8.0;
import {RLPReader} from "./RLPReader.sol";
library MerklePatriciaProof {
/*
* @dev Verifies a merkle patricia proof.
* @param value The terminating value in the trie.
* @param encodedPath The path in the trie leading to value.
* @param rlpParentNodes The rlp encoded stack of nodes.
* @param root The root hash of the trie.
* @return The boolean validity of the proof.
*/
function verify(
bytes memory value,
bytes memory encodedPath,
bytes memory rlpParentNodes,
bytes32 root
) internal pure returns (bool) {
RLPReader.RLPItem memory item = RLPReader.toRlpItem(rlpParentNodes);
RLPReader.RLPItem[] memory parentNodes = RLPReader.toList(item);
bytes memory currentNode;
RLPReader.RLPItem[] memory currentNodeList;
bytes32 nodeKey = root;
uint256 pathPtr = 0;
bytes memory path = _getNibbleArray(encodedPath);
if (path.length == 0) {
return false;
}
for (uint256 i = 0; i < parentNodes.length; i++) {
if (pathPtr > path.length) {
return false;
}
currentNode = RLPReader.toRlpBytes(parentNodes[i]);
if (nodeKey != keccak256(currentNode)) {
return false;
}
currentNodeList = RLPReader.toList(parentNodes[i]);
if (currentNodeList.length == 17) {
if (pathPtr == path.length) {
if (keccak256(RLPReader.toBytes(currentNodeList[16])) == keccak256(value)) {
return true;
} else {
return false;
}
}
uint8 nextPathNibble = uint8(path[pathPtr]);
if (nextPathNibble > 16) {
return false;
}
nodeKey = bytes32(RLPReader.toUintStrict(currentNodeList[nextPathNibble]));
pathPtr += 1;
} else if (currentNodeList.length == 2) {
uint256 traversed = _nibblesToTraverse(RLPReader.toBytes(currentNodeList[0]), path, pathPtr);
if (pathPtr + traversed == path.length) {
//leaf node
if (keccak256(RLPReader.toBytes(currentNodeList[1])) == keccak256(value)) {
return true;
} else {
return false;
}
}
//extension node
if (traversed == 0) {
return false;
}
pathPtr += traversed;
nodeKey = bytes32(RLPReader.toUintStrict(currentNodeList[1]));
} else {
return false;
}
}
}
function _nibblesToTraverse(
bytes memory encodedPartialPath,
bytes memory path,
uint256 pathPtr
) private pure returns (uint256) {
uint256 len = 0;
// encodedPartialPath has elements that are each two hex characters (1 byte), but partialPath
// and slicedPath have elements that are each one hex character (1 nibble)
bytes memory partialPath = _getNibbleArray(encodedPartialPath);
bytes memory slicedPath = new bytes(partialPath.length);
// pathPtr counts nibbles in path
// partialPath.length is a number of nibbles
for (uint256 i = pathPtr; i < pathPtr + partialPath.length; i++) {
bytes1 pathNibble = path[i];
slicedPath[i - pathPtr] = pathNibble;
}
if (keccak256(partialPath) == keccak256(slicedPath)) {
len = partialPath.length;
} else {
len = 0;
}
return len;
}
// bytes b must be hp encoded
function _getNibbleArray(bytes memory b) internal pure returns (bytes memory) {
bytes memory nibbles = "";
if (b.length > 0) {
uint8 offset;
uint8 hpNibble = uint8(_getNthNibbleOfBytes(0, b));
if (hpNibble == 1 || hpNibble == 3) {
nibbles = new bytes(b.length * 2 - 1);
bytes1 oddNibble = _getNthNibbleOfBytes(1, b);
nibbles[0] = oddNibble;
offset = 1;
} else {
nibbles = new bytes(b.length * 2 - 2);
offset = 0;
}
for (uint256 i = offset; i < nibbles.length; i++) {
nibbles[i] = _getNthNibbleOfBytes(i - offset + 2, b);
}
}
return nibbles;
}
function _getNthNibbleOfBytes(uint256 n, bytes memory str) private pure returns (bytes1) {
return bytes1(n % 2 == 0 ? uint8(str[n / 2]) / 0x10 : uint8(str[n / 2]) % 0x10);
}
}
/*
* @author Hamdi Allam [email protected]
* Please reach out with any questions or concerns
*/
pragma solidity ^0.8.0;
library RLPReader {
uint8 constant STRING_SHORT_START = 0x80;
uint8 constant STRING_LONG_START = 0xb8;
uint8 constant LIST_SHORT_START = 0xc0;
uint8 constant LIST_LONG_START = 0xf8;
uint8 constant WORD_SIZE = 32;
struct RLPItem {
uint256 len;
uint256 memPtr;
}
struct Iterator {
RLPItem item; // Item that's being iterated over.
uint256 nextPtr; // Position of the next item in the list.
}
/*
* @dev Returns the next element in the iteration. Reverts if it has not next element.
* @param self The iterator.
* @return The next element in the iteration.
*/
function next(Iterator memory self) internal pure returns (RLPItem memory) {
require(hasNext(self));
uint256 ptr = self.nextPtr;
uint256 itemLength = _itemLength(ptr);
self.nextPtr = ptr + itemLength;
return RLPItem(itemLength, ptr);
}
/*
* @dev Returns true if the iteration has more elements.
* @param self The iterator.
* @return true if the iteration has more elements.
*/
function hasNext(Iterator memory self) internal pure returns (bool) {
RLPItem memory item = self.item;
return self.nextPtr < item.memPtr + item.len;
}
/*
* @param item RLP encoded bytes
*/
function toRlpItem(bytes memory item) internal pure returns (RLPItem memory) {
uint256 memPtr;
assembly {
memPtr := add(item, 0x20)
}
return RLPItem(item.length, memPtr);
}
/*
* @dev Create an iterator. Reverts if item is not a list.
* @param self The RLP item.
* @return An 'Iterator' over the item.
*/
function iterator(RLPItem memory self) internal pure returns (Iterator memory) {
require(isList(self));
uint256 ptr = self.memPtr + _payloadOffset(self.memPtr);
return Iterator(self, ptr);
}
/*
* @param item RLP encoded bytes
*/
function rlpLen(RLPItem memory item) internal pure returns (uint256) {
return item.len;
}
/*
* @param item RLP encoded bytes
*/
function payloadLen(RLPItem memory item) internal pure returns (uint256) {
return item.len - _payloadOffset(item.memPtr);
}
/*
* @param item RLP encoded list in bytes
*/
function toList(RLPItem memory item) internal pure returns (RLPItem[] memory) {
require(isList(item));
uint256 items = numItems(item);
RLPItem[] memory result = new RLPItem[](items);
uint256 memPtr = item.memPtr + _payloadOffset(item.memPtr);
uint256 dataLen;
for (uint256 i = 0; i < items; i++) {
dataLen = _itemLength(memPtr);
result[i] = RLPItem(dataLen, memPtr);
memPtr = memPtr + dataLen;
}
return result;
}
// @return indicator whether encoded payload is a list. negate this function call for isData.
function isList(RLPItem memory item) internal pure returns (bool) {
if (item.len == 0) return false;
uint8 byte0;
uint256 memPtr = item.memPtr;
assembly {
byte0 := byte(0, mload(memPtr))
}
if (byte0 < LIST_SHORT_START) return false;
return true;
}
/*
* @dev A cheaper version of keccak256(toRlpBytes(item)) that avoids copying memory.
* @return keccak256 hash of RLP encoded bytes.
*/
function rlpBytesKeccak256(RLPItem memory item) internal pure returns (bytes32) {
uint256 ptr = item.memPtr;
uint256 len = item.len;
bytes32 result;
assembly {
result := keccak256(ptr, len)
}
return result;
}
function payloadLocation(RLPItem memory item) internal pure returns (uint256, uint256) {
uint256 offset = _payloadOffset(item.memPtr);
uint256 memPtr = item.memPtr + offset;
uint256 len = item.len - offset; // data length
return (memPtr, len);
}
/*
* @dev A cheaper version of keccak256(toBytes(item)) that avoids copying memory.
* @return keccak256 hash of the item payload.
*/
function payloadKeccak256(RLPItem memory item) internal pure returns (bytes32) {
(uint256 memPtr, uint256 len) = payloadLocation(item);
bytes32 result;
assembly {
result := keccak256(memPtr, len)
}
return result;
}
/** RLPItem conversions into data types **/
// @returns raw rlp encoding in bytes
function toRlpBytes(RLPItem memory item) internal pure returns (bytes memory) {
bytes memory result = new bytes(item.len);
if (result.length == 0) return result;
uint256 ptr;
assembly {
ptr := add(0x20, result)
}
copy(item.memPtr, ptr, item.len);
return result;
}
// any non-zero byte is considered true
function toBoolean(RLPItem memory item) internal pure returns (bool) {
require(item.len == 1);
uint256 result;
uint256 memPtr = item.memPtr;
assembly {
result := byte(0, mload(memPtr))
}
return result == 0 ? false : true;
}
function toAddress(RLPItem memory item) internal pure returns (address) {
// 1 byte for the length prefix
require(item.len == 21);
return address(uint160(toUint(item)));
}
function toUint(RLPItem memory item) internal pure returns (uint256) {
require(item.len > 0 && item.len <= 33);
uint256 offset = _payloadOffset(item.memPtr);
uint256 len = item.len - offset;
uint256 result;
uint256 memPtr = item.memPtr + offset;
assembly {
result := mload(memPtr)
// shfit to the correct location if neccesary
if lt(len, 32) {
result := div(result, exp(256, sub(32, len)))
}
}
return result;
}
// enforces 32 byte length
function toUintStrict(RLPItem memory item) internal pure returns (uint256) {
// one byte prefix
require(item.len == 33);
uint256 result;
uint256 memPtr = item.memPtr + 1;
assembly {
result := mload(memPtr)
}
return result;
}
function toBytes(RLPItem memory item) internal pure returns (bytes memory) {
require(item.len > 0);
uint256 offset = _payloadOffset(item.memPtr);
uint256 len = item.len - offset; // data length
bytes memory result = new bytes(len);
uint256 destPtr;
assembly {
destPtr := add(0x20, result)
}
copy(item.memPtr + offset, destPtr, len);
return result;
}
/*
* Private Helpers
*/
// @return number of payload items inside an encoded list.
function numItems(RLPItem memory item) private pure returns (uint256) {
if (item.len == 0) return 0;
uint256 count = 0;
uint256 currPtr = item.memPtr + _payloadOffset(item.memPtr);
uint256 endPtr = item.memPtr + item.len;
while (currPtr < endPtr) {
currPtr = currPtr + _itemLength(currPtr); // skip over an item
count++;
}
return count;
}
// @return entire rlp item byte length
function _itemLength(uint256 memPtr) private pure returns (uint256) {
uint256 itemLen;
uint256 byte0;
assembly {
byte0 := byte(0, mload(memPtr))
}
if (byte0 < STRING_SHORT_START) itemLen = 1;
else if (byte0 < STRING_LONG_START) itemLen = byte0 - STRING_SHORT_START + 1;
else if (byte0 < LIST_SHORT_START) {
assembly {
let byteLen := sub(byte0, 0xb7) // # of bytes the actual length is
memPtr := add(memPtr, 1) // skip over the first byte
/* 32 byte word size */
let dataLen := div(mload(memPtr), exp(256, sub(32, byteLen))) // right shifting to get the len
itemLen := add(dataLen, add(byteLen, 1))
}
} else if (byte0 < LIST_LONG_START) {
itemLen = byte0 - LIST_SHORT_START + 1;
} else {
assembly {
let byteLen := sub(byte0, 0xf7)
memPtr := add(memPtr, 1)
let dataLen := div(mload(memPtr), exp(256, sub(32, byteLen))) // right shifting to the correct length
itemLen := add(dataLen, add(byteLen, 1))
}
}
return itemLen;
}
// @return number of bytes until the data
function _payloadOffset(uint256 memPtr) private pure returns (uint256) {
uint256 byte0;
assembly {
byte0 := byte(0, mload(memPtr))
}
if (byte0 < STRING_SHORT_START) return 0;
else if (byte0 < STRING_LONG_START || (byte0 >= LIST_SHORT_START && byte0 < LIST_LONG_START)) return 1;
else if (byte0 < LIST_SHORT_START)
// being explicit
return byte0 - (STRING_LONG_START - 1) + 1;
else return byte0 - (LIST_LONG_START - 1) + 1;
}
/*
* @param src Pointer to source
* @param dest Pointer to destination
* @param len Amount of memory to copy from the source
*/
function copy(
uint256 src,
uint256 dest,
uint256 len
) private pure {
if (len == 0) return;
// copy as many word sizes as possible
for (; len >= WORD_SIZE; len -= WORD_SIZE) {
assembly {
mstore(dest, mload(src))
}
src += WORD_SIZE;
dest += WORD_SIZE;
}
if (len == 0) return;
// left over bytes. Mask is used to remove unwanted bytes from the word
uint256 mask = 256**(WORD_SIZE - len) - 1;
assembly {
let srcpart := and(mload(src), not(mask)) // zero out src
let destpart := and(mload(dest), mask) // retrieve the bytes
mstore(dest, or(destpart, srcpart))
}
}
}
// SPDX-License-Identifier: MIT
pragma solidity ^0.8.0;
import {RLPReader} from "../lib/RLPReader.sol";
import {MerklePatriciaProof} from "../lib/MerklePatriciaProof.sol";
import {Merkle} from "../lib/Merkle.sol";
import "../lib/ExitPayloadReader.sol";
interface IFxStateSender {
function sendMessageToChild(address _receiver, bytes calldata _data) external;
}
contract ICheckpointManager {
struct HeaderBlock {
bytes32 root;
uint256 start;
uint256 end;
uint256 createdAt;
address proposer;
}
/**
* @notice mapping of checkpoint header numbers to block details
* @dev These checkpoints are submited by plasma contracts
*/
mapping(uint256 => HeaderBlock) public headerBlocks;
}
abstract contract FxBaseRootTunnel {
using RLPReader for RLPReader.RLPItem;
using Merkle for bytes32;
using ExitPayloadReader for bytes;
using ExitPayloadReader for ExitPayloadReader.ExitPayload;
using ExitPayloadReader for ExitPayloadReader.Log;
using ExitPayloadReader for ExitPayloadReader.LogTopics;
using ExitPayloadReader for ExitPayloadReader.Receipt;
// keccak256(MessageSent(bytes))
bytes32 public constant SEND_MESSAGE_EVENT_SIG = 0x8c5261668696ce22758910d05bab8f186d6eb247ceac2af2e82c7dc17669b036;
// state sender contract
IFxStateSender public fxRoot;
// root chain manager
ICheckpointManager public checkpointManager;
// child tunnel contract which receives and sends messages
address public fxChildTunnel;
// storage to avoid duplicate exits
mapping(bytes32 => bool) public processedExits;
constructor(address _checkpointManager, address _fxRoot) {
checkpointManager = ICheckpointManager(_checkpointManager);
fxRoot = IFxStateSender(_fxRoot);
}
// set fxChildTunnel if not set already
function setFxChildTunnel(address _fxChildTunnel) public {
require(fxChildTunnel == address(0x0), "FxBaseRootTunnel: CHILD_TUNNEL_ALREADY_SET");
fxChildTunnel = _fxChildTunnel;
}
/**
* @notice Send bytes message to Child Tunnel
* @param message bytes message that will be sent to Child Tunnel
* some message examples -
* abi.encode(tokenId);
* abi.encode(tokenId, tokenMetadata);
* abi.encode(messageType, messageData);
*/
function _sendMessageToChild(bytes memory message) internal {
fxRoot.sendMessageToChild(fxChildTunnel, message);
}
function _validateAndExtractMessage(bytes memory inputData) internal returns (bytes memory) {
ExitPayloadReader.ExitPayload memory payload = inputData.toExitPayload();
bytes memory branchMaskBytes = payload.getBranchMaskAsBytes();
uint256 blockNumber = payload.getBlockNumber();
// checking if exit has already been processed
// unique exit is identified using hash of (blockNumber, branchMask, receiptLogIndex)
bytes32 exitHash = keccak256(
abi.encodePacked(
blockNumber,
// first 2 nibbles are dropped while generating nibble array
// this allows branch masks that are valid but bypass exitHash check (changing first 2 nibbles only)
// so converting to nibble array and then hashing it
MerklePatriciaProof._getNibbleArray(branchMaskBytes),
payload.getReceiptLogIndex()
)
);
require(processedExits[exitHash] == false, "FxRootTunnel: EXIT_ALREADY_PROCESSED");
processedExits[exitHash] = true;
ExitPayloadReader.Receipt memory receipt = payload.getReceipt();
ExitPayloadReader.Log memory log = receipt.getLog();
// check child tunnel
require(fxChildTunnel == log.getEmitter(), "FxRootTunnel: INVALID_FX_CHILD_TUNNEL");
bytes32 receiptRoot = payload.getReceiptRoot();
// verify receipt inclusion
require(
MerklePatriciaProof.verify(receipt.toBytes(), branchMaskBytes, payload.getReceiptProof(), receiptRoot),
"FxRootTunnel: INVALID_RECEIPT_PROOF"
);
// verify checkpoint inclusion
_checkBlockMembershipInCheckpoint(
blockNumber,
payload.getBlockTime(),
payload.getTxRoot(),
receiptRoot,
payload.getHeaderNumber(),
payload.getBlockProof()
);
ExitPayloadReader.LogTopics memory topics = log.getTopics();
require(
bytes32(topics.getField(0).toUint()) == SEND_MESSAGE_EVENT_SIG, // topic0 is event sig
"FxRootTunnel: INVALID_SIGNATURE"
);
// received message data
bytes memory message = abi.decode(log.getData(), (bytes)); // event decodes params again, so decoding bytes to get message
return message;
}
function _checkBlockMembershipInCheckpoint(
uint256 blockNumber,
uint256 blockTime,
bytes32 txRoot,
bytes32 receiptRoot,
uint256 headerNumber,
bytes memory blockProof
) private view returns (uint256) {
(bytes32 headerRoot, uint256 startBlock, , uint256 createdAt, ) = checkpointManager.headerBlocks(headerNumber);
require(
keccak256(abi.encodePacked(blockNumber, blockTime, txRoot, receiptRoot)).checkMembership(
blockNumber - startBlock,
headerRoot,
blockProof
),
"FxRootTunnel: INVALID_HEADER"
);
return createdAt;
}
/**
* @notice receive message from L2 to L1, validated by proof
* @dev This function verifies if the transaction actually happened on child chain
*
* @param inputData RLP encoded data of the reference tx containing following list of fields
* 0 - headerNumber - Checkpoint header block number containing the reference tx
* 1 - blockProof - Proof that the block header (in the child chain) is a leaf in the submitted merkle root
* 2 - blockNumber - Block number containing the reference tx on child chain
* 3 - blockTime - Reference tx block time
* 4 - txRoot - Transactions root of block
* 5 - receiptRoot - Receipts root of block
* 6 - receipt - Receipt of the reference transaction
* 7 - receiptProof - Merkle proof of the reference receipt
* 8 - branchMask - 32 bits denoting the path of receipt in merkle tree
* 9 - receiptLogIndex - Log Index to read from the receipt
*/
function receiveMessage(bytes memory inputData) public virtual {
bytes memory message = _validateAndExtractMessage(inputData);
_processMessageFromChild(message);
}
/**
* @notice Process message received from Child Tunnel
* @dev function needs to be implemented to handle message as per requirement
* This is called by onStateReceive function.
* Since it is called via a system call, any event will not be emitted during its execution.
* @param message bytes message that was sent from Child Tunnel
*/
function _processMessageFromChild(bytes memory message) internal virtual;
}
// SPDX-License-Identifier: MIT
pragma solidity >=0.6.12 <=0.8.9;
pragma experimental ABIEncoderV2;
import "../interfaces/IMessengerWrapper.sol";
contract IL1Bridge {
struct TransferBond {
address bonder;
uint256 createdAt;
uint256 totalAmount;
uint256 challengeStartTime;
address challenger;
bool challengeResolved;
}
uint256 public challengePeriod;
mapping(bytes32 => TransferBond) public transferBonds;
function getIsBonder(address maybeBonder) public view returns (bool) {}
function getTransferRootId(bytes32 rootHash, uint256 totalAmount) public pure returns (bytes32) {}
function confirmTransferRoot(
uint256 originChainId,
bytes32 rootHash,
uint256 destinationChainId,
uint256 totalAmount,
uint256 rootCommittedAt
)
external
{}
}
abstract contract MessengerWrapper is IMessengerWrapper {
address public immutable l1BridgeAddress;
uint256 public immutable l2ChainId;
bool public isRootConfirmation = false;
constructor(address _l1BridgeAddress, uint256 _l2ChainId) internal {
l1BridgeAddress = _l1BridgeAddress;
l2ChainId = _l2ChainId;
}
modifier onlyL1Bridge {
require(msg.sender == l1BridgeAddress, "MW: Sender must be the L1 Bridge");
_;
}
modifier rootConfirmation {
isRootConfirmation = true;
_;
isRootConfirmation = false;
}
/**
* @dev Confirm roots that have bonded on L1 and passed the challenge period with no challenge
* @param rootHashes The root hashes to confirm
* @param destinationChainIds The destinationChainId of the roots to confirm
* @param totalAmounts The totalAmount of the roots to confirm
* @param rootCommittedAts The rootCommittedAt of the roots to confirm
*/
function confirmRoots (
bytes32[] calldata rootHashes,
uint256[] calldata destinationChainIds,
uint256[] calldata totalAmounts,
uint256[] calldata rootCommittedAts
) external override rootConfirmation {
IL1Bridge l1Bridge = IL1Bridge(l1BridgeAddress);
require(l1Bridge.getIsBonder(msg.sender), "MW: Sender must be a bonder");
require(rootHashes.length == totalAmounts.length, "MW: rootHashes and totalAmounts must be the same length");
uint256 challengePeriod = l1Bridge.challengePeriod();
for (uint256 i = 0; i < rootHashes.length; i++) {
bool canConfirm = canConfirmRoot(l1Bridge, rootHashes[i], totalAmounts[i], challengePeriod);
require(canConfirm, "MW: Root cannot be confirmed");
l1Bridge.confirmTransferRoot(
l2ChainId,
rootHashes[i],
destinationChainIds[i],
totalAmounts[i],
rootCommittedAts[i]
);
}
}
function canConfirmRoot (IL1Bridge l1Bridge, bytes32 rootHash, uint256 totalAmount, uint256 challengePeriod) public view returns (bool) {
bytes32 transferRootId = l1Bridge.getTransferRootId(rootHash, totalAmount);
(,uint256 createdAt,,uint256 challengeStartTime,,) = l1Bridge.transferBonds(transferRootId);
uint256 timeSinceBondCreation = block.timestamp - createdAt;
if (
createdAt != 0 &&
challengeStartTime == 0 &&
timeSinceBondCreation > challengePeriod
) {
return true;
}
return false;
}
}
// SPDX-License-Identifier: MIT
// @unsupported: ovm
pragma solidity 0.8.9;
pragma experimental ABIEncoderV2;
import "../polygon/tunnel/FxBaseRootTunnel.sol";
import "./MessengerWrapper.sol";
/**
* @dev A MessengerWrapper for Polygon - https://docs.matic.network/docs
* @notice Deployed on layer-1
*/
contract PolygonMessengerWrapper is FxBaseRootTunnel, MessengerWrapper {
constructor(
address _l1BridgeAddress,
address _checkpointManager,
address _fxRoot,
address _fxChildTunnel,
uint256 _l2ChainId
)
public
MessengerWrapper(_l1BridgeAddress, _l2ChainId)
FxBaseRootTunnel(_checkpointManager, _fxRoot)
{
setFxChildTunnel(_fxChildTunnel);
}
/**
* @dev Sends a message to the l2MessengerProxy from layer-1
* @param _calldata The data that l2MessengerProxy will be called with
* @notice The msg.sender is sent to the L2_PolygonMessengerProxy and checked there.
*/
function sendCrossDomainMessage(bytes memory _calldata) public override {
_sendMessageToChild(
abi.encode(msg.sender, _calldata)
);
}
function verifySender(address l1BridgeCaller, bytes memory /*_data*/) public view override {
if (isRootConfirmation) return;
require(l1BridgeCaller == address(this), "L1_PLGN_WPR: Caller must be this contract");
}
function _processMessageFromChild(bytes memory message) internal override {
(bool success,) = l1BridgeAddress.call(message);
require(success, "L1_PLGN_WPR: Call to L1 Bridge failed");
}
}