tornado-contracts/contracts/Governance/v4-exploit-patch/GovernanceExploitPatchUpgrade.sol
2024-03-29 21:52:45 +00:00

74 lines
2.4 KiB
Solidity

// SPDX-License-Identifier: MIT
pragma solidity ^0.6.12;
pragma experimental ABIEncoderV2;
import { Governance } from "../v1/Governance.sol";
import { GovernanceStakingUpgrade } from "../v3-relayer-registry/GovernanceStakingUpgrade.sol";
contract GovernanceExploitPatchUpgrade is GovernanceStakingUpgrade {
mapping(uint256 => bytes32) public proposalCodehashes;
constructor(address stakingRewardsAddress, address gasCompLogic, address userVaultAddress)
public
GovernanceStakingUpgrade(stakingRewardsAddress, gasCompLogic, userVaultAddress)
{ }
/// @notice Return the version of the contract
function version() external pure virtual override returns (string memory) {
return "4.patch-exploit";
}
/**
* @notice Execute a proposal
* @dev This upgrade should protect against Metamorphic contracts by comparing the proposal's extcodehash with a stored one
* @param proposalId The proposal's ID
*/
function execute(uint256 proposalId) public payable virtual override(Governance) {
require(msg.sender != address(this), "Governance::propose: pseudo-external function");
Proposal storage proposal = proposals[proposalId];
address target = proposal.target;
bytes32 proposalCodehash;
assembly {
proposalCodehash := extcodehash(target)
}
require(
proposalCodehash == proposalCodehashes[proposalId],
"Governance::propose: metamorphic contracts not allowed"
);
super.execute(proposalId);
}
/**
* @notice Internal function called from propoese
* @dev This should store the extcodehash of the proposal contract
* @param proposer proposer address
* @param target smart contact address that will be executed as result of voting
* @param description description of the proposal
* @return proposalId new proposal id
*/
function _propose(address proposer, address target, string memory description)
internal
virtual
override(Governance)
returns (uint256 proposalId)
{
// Implies all former predicates were valid
proposalId = super._propose(proposer, target, description);
bytes32 proposalCodehash;
assembly {
proposalCodehash := extcodehash(target)
}
proposalCodehashes[proposalId] = proposalCodehash;
}
}