// SPDX-License-Identifier: LGPL-3.0-only
pragma solidity >=0.7.0 <0.9.0;
/// @title Multi Send - Allows to batch multiple transactions into one.
/// @author Nick Dodson - <nick.dodson@consensys.net>
/// @author Gonçalo Sá - <goncalo.sa@consensys.net>
/// @author Stefan George - <stefan@gnosis.io>
/// @author Richard Meissner - <richard@gnosis.io>
contract MultiSend {
address private immutable multisendSingleton;
constructor() {
multisendSingleton = address(this);
}
/// @dev Sends multiple transactions and reverts all if one fails.
/// @param transactions Encoded transactions. Each transaction is encoded as a packed bytes of
/// operation as a uint8 with 0 for a call or 1 for a delegatecall (=> 1 byte),
/// to as a address (=> 20 bytes),
/// value as a uint256 (=> 32 bytes),
/// data length as a uint256 (=> 32 bytes),
/// data as bytes.
/// see abi.encodePacked for more information on packed encoding
/// @notice This method is payable as delegatecalls keep the msg.value from the previous call
/// If the calling method (e.g. execTransaction) received ETH this would revert otherwise
function multiSend(bytes memory transactions) public payable {
require(address(this) != multisendSingleton, "MultiSend should only be called via delegatecall");
// solhint-disable-next-line no-inline-assembly
assembly {
let length := mload(transactions)
let i := 0x20
for {
// Pre block is not used in "while mode"
} lt(i, length) {
// Post block is not used in "while mode"
} {
// First byte of the data is the operation.
// We shift by 248 bits (256 - 8 [operation byte]) it right since mload will always load 32 bytes (a word).
// This will also zero out unused data.
let operation := shr(0xf8, mload(add(transactions, i)))
// We offset the load address by 1 byte (operation byte)
// We shift it right by 96 bits (256 - 160 [20 address bytes]) to right-align the data and zero out unused data.
let to := shr(0x60, mload(add(transactions, add(i, 0x01))))
// We offset the load address by 21 byte (operation byte + 20 address bytes)
let value := mload(add(transactions, add(i, 0x15)))
// We offset the load address by 53 byte (operation byte + 20 address bytes + 32 value bytes)
let dataLength := mload(add(transactions, add(i, 0x35)))
// We offset the load address by 85 byte (operation byte + 20 address bytes + 32 value bytes + 32 data length bytes)
let data := add(transactions, add(i, 0x55))
let success := 0
switch operation
case 0 {
success := call(gas(), to, value, data, dataLength, 0, 0)
}
case 1 {
success := delegatecall(gas(), to, data, dataLength, 0, 0)
}
if eq(success, 0) {
revert(0, 0)
}
// Next entry starts at 85 byte + data length
i := add(i, add(0x55, dataLength))
}
}
}
}
