ETH Price: $2,007.77 (-2.48%)

Transaction Decoder

Block:
23733726 at Nov-05-2025 02:34:59 PM +UTC
Transaction Fee:
0.00072835072444155 ETH $1.46
Gas Used:
235,745 Gas / 3.08957019 Gwei

Emitted Events:

521 0x2e7b0d4f9b2eaf782ed3d160e3a0a4b1a7930ada.0xddf252ad1be2c89b69c2b068fc378daa952ba7f163c4a11628f55a4df523b3ef( 0xddf252ad1be2c89b69c2b068fc378daa952ba7f163c4a11628f55a4df523b3ef, 0x0000000000000000000000007510792a3b1969f9307f3845ce88e39578f2bae1, 0x00000000000000000000000087a698a328694dfb77d4abbf9e471d11f3490285, 0000000000000000000000000000000000000000000000000000377b7814d7c9 )
522 OriginalTokenVaultV2.Withdrawn( withdrawId=DBCBC148110A043EF7FE976A346CB74A60F24B0C68D2AA6D47CAC7A09316A982, receiver=[Sender] 0x87a698a328694dfb77d4abbf9e471d11f3490285, token=0x2e7b0d4f9b2eaf782ed3d160e3a0a4b1a7930ada, amount=61003435136969, refChainId=0, refId=0000000000000000000000000000000000000000000000000000019A5470A111, burnAccount=0x00000000...000000000 )

Account State Difference:

  Address   Before After State Difference Code
0x2e7B0d4F...1a7930aDA
(Titan Builder)
11.377805225412244597 Eth11.378276715412244597 Eth0.00047149
0x7510792A...578f2bAE1
(Celer Network: Original Token Vault V2)
0x87A698a3...1F3490285
0.147611560219786624 Eth
Nonce: 43
0.146883209495345074 Eth
Nonce: 44
0.00072835072444155

Execution Trace

OriginalTokenVaultV2.withdraw( _request=0x0A142E7B0D4F9B2EAF782ED3D160E3A0A4B1A7930ADA121487A698A328694DFB77D4ABBF9E471D11F34902851A06377B7814D7C92214000000000000000000000000000000000000000032200000000000000000000000000000000000000000000000000000019A5470A111, _sigs=[fyLVJQbC62oksd4p1JH4UIDUeC2EKrp+s0WcplCA7jg07R2hxQEbghRbHB8k40Easj+xq1iTwHiiQvFPKlnJyRw=, /I1t84pKV26VXdJje9/p9wUXTPOyAjMg3E14hml9mWBHLhOEMNCe1GNCSxZ05FlVtGL7l6xdx1XMTXWQdriH+Bw=, F1NVI6fR1Jr0gQLiOBGAVlq+7SRHSMvXY5SjZ3qqnOg4NMz9CNVp9vijjpSKpu9x446JVuLaGll8H+xoE5EDohw=, Xr+z8TIkgpYfiyp60mCyAEQloGLWGc6NFqDHFR2g33litkwecORwj1xYFfzAnlbBrrpW6sx3IYP0uMgi+pxV9hw=, w820BzUENNi++f4QogNhE8bvJX68MWkBaoB9m5luUOc1ePDju+m5DMyFL14iPPc8PMhCLTRS0n0bGhg6Tffrihw=, U5TdyyL5gZwg+ud/BBlToLJfgCgnDjW2YcffrwHb3oROwi8++WW+HsX7qmlKOIn4lTvtCzw/WKXfVdyccOwUJxw=, t27zwF/tlc1uzW3z9Xp/IX+9sNAddcUHjkl0WTEMO1lNtTXVFRx9y0cUXC+BdUVE7zMZVfSJA6RF46SijSUnOhw=, 9Q4ZyEfVSRn3RA7msYtJ+g1wXWGkOY7r6Y92+GnUqpJhUQmXexLivJapGOt5UqkE8ckq0ZXc9TjjsDoWqDt5CBs=, 2qcj7uAKETwn0jqBeifpRfxfXQFM4KxSNKTAAugxq2oL/tNecnR6VQYdWDuJFYkK5QkHMCb6Rm13iaRi/b1TKxw=, DH1kIcRl5+geXgGlryGc+HMGrAlFKu6J2pIsentHU+8GA0mHOXR6IDKExhYRy1sQoWp6YcFUogFZfvZioeS6lBw=, h+gOj0H0bMXeThYU8kS9cJH/DFbQO5yZzOk6USJOC2YpEEijzoYo5ofh4gbWdSUfc7JtgSdfD7OTHQS4PDK0qRw=, jrh2Zau/ZaNPzI128qBinLiXC3tRu+j0E5S4n/0vpIUbbBmeDCnZGO2Gwdnj48/neInSyelWU7oM5m7c9mr6Jhs=, IgzVkQUKdF4vS5vzbmryhUUaFj7pob+QE5fs8bjZiDt6LbyxhFm2WJ4DKy2/3dnmtsnp4+o18SP9xESEjcrTUBs=, TwiwrXYD1tnhO6sTuJx0uIRJmErFAvMvqVT9f3MnGgoBZSUCz4+Hb0z/DjtZJ7VripY9w4d0cHsL211Y2Nn0Wxw=, S0C9FEucG6WCYXcmFkbSc+5j6w2tX5htQx6nHi+qT+kWjRKa+VUbSQbhlJYa+gRb42vXpJKtPilsvB6diHck2hs=], _signers=[0x241A100333EEfA2efC389Ec836A6fF619fC1c644, 0x273035E10F106499efAce385DbA07135E7cC8E54, 0x55f4A1BFc655cf55eD325F2338a1deE84f754Df2, 0x57c96a00F9fF7B25CB5Cf964F1A191BE9321b8c8, 0x870cF8Dd5d9C8eB1403dfd6e6A4753f4d617A538, 0x954ADc74481634b4d278C459853b4e6cc17aE8D2, 0x98E9D288743839e96A8005a6B51C770Bbf7788C0, 0x9a66644084108a1bC23A9cCd50d6d63E53098dB6, 0x9a8CFAcF513fB3d5E39F5952C8608e985B3DC6eF, 0x9AC5279013EdfEC74c5c2976FC831Ad0527402E0, 0x9Cd5006e1BfF785dad5869efd81a2c42545C9d9b, 0xa73B339c3fae27bedf7Cb72D9D000b08fc899609, 0xbfa2F68bf9Ad60Dc3cFB1cEF04730Eb7FA251424, 0xc74ACAb8C0a340f585d008cB521d64d2554171A8, 0xcF12DD34d7597D06ff98F85d2B9483D9D5f7D952, 0xd10c833f4305E1053a64Bc738c550381f48104Ca, 0xF4151eEbFa1B9C87dD92c8243A18B1bAEf8C1813, 0xF5AD7f3782E8A67BffA297684e27CF9fCC781Be1, 0xF6e93Eb288658de5E2E982f99D2b378B22959d15], _powers=[56793518230000000000000000, 2436355772780000000000000, 49278824220000000000000000, 100244762760000000000000000, 99010000000000000000000000, 52531350260000000000000000, 279730606849500000000000000, 297223415323902544900122309, 75066473869855875047493668, 69019069260000000000000000, 128324525360000000000000000, 9363709387622190000000000, 244342775268641991500000000, 175407252320000000000000000, 72289672750000000000000000, 167717546850000000000000000, 81713184870000000000000000, 146324520000000000000000, 20000000000000000000000] ) => ( DBCBC148110A043EF7FE976A346CB74A60F24B0C68D2AA6D47CAC7A09316A982 )
  • Bridge.verifySigs( _msg=0xE02462859DC41BC9BE16513E607FAD0FDAA45E8B202733AB051153F2C130BCFB0A142E7B0D4F9B2EAF782ED3D160E3A0A4B1A7930ADA121487A698A328694DFB77D4ABBF9E471D11F34902851A06377B7814D7C92214000000000000000000000000000000000000000032200000000000000000000000000000000000000000000000000000019A5470A111, _sigs=[fyLVJQbC62oksd4p1JH4UIDUeC2EKrp+s0WcplCA7jg07R2hxQEbghRbHB8k40Easj+xq1iTwHiiQvFPKlnJyRw=, /I1t84pKV26VXdJje9/p9wUXTPOyAjMg3E14hml9mWBHLhOEMNCe1GNCSxZ05FlVtGL7l6xdx1XMTXWQdriH+Bw=, F1NVI6fR1Jr0gQLiOBGAVlq+7SRHSMvXY5SjZ3qqnOg4NMz9CNVp9vijjpSKpu9x446JVuLaGll8H+xoE5EDohw=, Xr+z8TIkgpYfiyp60mCyAEQloGLWGc6NFqDHFR2g33litkwecORwj1xYFfzAnlbBrrpW6sx3IYP0uMgi+pxV9hw=, w820BzUENNi++f4QogNhE8bvJX68MWkBaoB9m5luUOc1ePDju+m5DMyFL14iPPc8PMhCLTRS0n0bGhg6Tffrihw=, U5TdyyL5gZwg+ud/BBlToLJfgCgnDjW2YcffrwHb3oROwi8++WW+HsX7qmlKOIn4lTvtCzw/WKXfVdyccOwUJxw=, t27zwF/tlc1uzW3z9Xp/IX+9sNAddcUHjkl0WTEMO1lNtTXVFRx9y0cUXC+BdUVE7zMZVfSJA6RF46SijSUnOhw=, 9Q4ZyEfVSRn3RA7msYtJ+g1wXWGkOY7r6Y92+GnUqpJhUQmXexLivJapGOt5UqkE8ckq0ZXc9TjjsDoWqDt5CBs=, 2qcj7uAKETwn0jqBeifpRfxfXQFM4KxSNKTAAugxq2oL/tNecnR6VQYdWDuJFYkK5QkHMCb6Rm13iaRi/b1TKxw=, DH1kIcRl5+geXgGlryGc+HMGrAlFKu6J2pIsentHU+8GA0mHOXR6IDKExhYRy1sQoWp6YcFUogFZfvZioeS6lBw=, h+gOj0H0bMXeThYU8kS9cJH/DFbQO5yZzOk6USJOC2YpEEijzoYo5ofh4gbWdSUfc7JtgSdfD7OTHQS4PDK0qRw=, jrh2Zau/ZaNPzI128qBinLiXC3tRu+j0E5S4n/0vpIUbbBmeDCnZGO2Gwdnj48/neInSyelWU7oM5m7c9mr6Jhs=, IgzVkQUKdF4vS5vzbmryhUUaFj7pob+QE5fs8bjZiDt6LbyxhFm2WJ4DKy2/3dnmtsnp4+o18SP9xESEjcrTUBs=, TwiwrXYD1tnhO6sTuJx0uIRJmErFAvMvqVT9f3MnGgoBZSUCz4+Hb0z/DjtZJ7VripY9w4d0cHsL211Y2Nn0Wxw=, S0C9FEucG6WCYXcmFkbSc+5j6w2tX5htQx6nHi+qT+kWjRKa+VUbSQbhlJYa+gRb42vXpJKtPilsvB6diHck2hs=], _signers=[0x241A100333EEfA2efC389Ec836A6fF619fC1c644, 0x273035E10F106499efAce385DbA07135E7cC8E54, 0x55f4A1BFc655cf55eD325F2338a1deE84f754Df2, 0x57c96a00F9fF7B25CB5Cf964F1A191BE9321b8c8, 0x870cF8Dd5d9C8eB1403dfd6e6A4753f4d617A538, 0x954ADc74481634b4d278C459853b4e6cc17aE8D2, 0x98E9D288743839e96A8005a6B51C770Bbf7788C0, 0x9a66644084108a1bC23A9cCd50d6d63E53098dB6, 0x9a8CFAcF513fB3d5E39F5952C8608e985B3DC6eF, 0x9AC5279013EdfEC74c5c2976FC831Ad0527402E0, 0x9Cd5006e1BfF785dad5869efd81a2c42545C9d9b, 0xa73B339c3fae27bedf7Cb72D9D000b08fc899609, 0xbfa2F68bf9Ad60Dc3cFB1cEF04730Eb7FA251424, 0xc74ACAb8C0a340f585d008cB521d64d2554171A8, 0xcF12DD34d7597D06ff98F85d2B9483D9D5f7D952, 0xd10c833f4305E1053a64Bc738c550381f48104Ca, 0xF4151eEbFa1B9C87dD92c8243A18B1bAEf8C1813, 0xF5AD7f3782E8A67BffA297684e27CF9fCC781Be1, 0xF6e93Eb288658de5E2E982f99D2b378B22959d15], _powers=[56793518230000000000000000, 2436355772780000000000000, 49278824220000000000000000, 100244762760000000000000000, 99010000000000000000000000, 52531350260000000000000000, 279730606849500000000000000, 297223415323902544900122309, 75066473869855875047493668, 69019069260000000000000000, 128324525360000000000000000, 9363709387622190000000000, 244342775268641991500000000, 175407252320000000000000000, 72289672750000000000000000, 167717546850000000000000000, 81713184870000000000000000, 146324520000000000000000, 20000000000000000000000] )
    • Null: 0x000...001.3f2322f1( )
    • Null: 0x000...001.3f2322f1( )
    • Null: 0x000...001.3f2322f1( )
    • Null: 0x000...001.3f2322f1( )
    • Null: 0x000...001.3f2322f1( )
    • Null: 0x000...001.3f2322f1( )
    • Null: 0x000...001.3f2322f1( )
    • Null: 0x000...001.3f2322f1( )
    • Null: 0x000...001.3f2322f1( )
    • Null: 0x000...001.3f2322f1( )
    • Null: 0x000...001.3f2322f1( )
    • Ceres: CERES Token.a9059cbb( )
      File 1 of 2: OriginalTokenVaultV2
      // SPDX-License-Identifier: GPL-3.0-only
      pragma solidity 0.8.9;
      import "@openzeppelin/contracts/token/ERC20/IERC20.sol";
      import "@openzeppelin/contracts/token/ERC20/utils/SafeERC20.sol";
      import "@openzeppelin/contracts/security/ReentrancyGuard.sol";
      import "../interfaces/ISigsVerifier.sol";
      import "../interfaces/IWETH.sol";
      import "../libraries/PbPegged.sol";
      import "../safeguard/Pauser.sol";
      import "../safeguard/VolumeControl.sol";
      import "../safeguard/DelayedTransfer.sol";
      /**
       * @title the vault to deposit and withdraw original tokens
       * @dev Work together with PeggedTokenBridge contracts deployed at remote chains
       */
      contract OriginalTokenVaultV2 is ReentrancyGuard, Pauser, VolumeControl, DelayedTransfer {
          using SafeERC20 for IERC20;
          ISigsVerifier public immutable sigsVerifier;
          mapping(bytes32 => bool) public records;
          mapping(address => uint256) public minDeposit;
          mapping(address => uint256) public maxDeposit;
          address public nativeWrap;
          event Deposited(
              bytes32 depositId,
              address depositor,
              address token,
              uint256 amount,
              uint64 mintChainId,
              address mintAccount,
              uint64 nonce
          );
          event Withdrawn(
              bytes32 withdrawId,
              address receiver,
              address token,
              uint256 amount,
              // ref_chain_id defines the reference chain ID, taking values of:
              // 1. The common case of burn-withdraw: the chain ID on which the corresponding burn happened;
              // 2. Pegbridge fee claim: zero / not applicable;
              // 3. Refund for wrong deposit: this chain ID on which the deposit happened
              uint64 refChainId,
              // ref_id defines a unique reference ID, taking values of:
              // 1. The common case of burn-withdraw: the burn ID on the remote chain;
              // 2. Pegbridge fee claim: a per-account nonce;
              // 3. Refund for wrong deposit: the deposit ID on this chain
              bytes32 refId,
              address burnAccount
          );
          event MinDepositUpdated(address token, uint256 amount);
          event MaxDepositUpdated(address token, uint256 amount);
          constructor(ISigsVerifier _sigsVerifier) {
              sigsVerifier = _sigsVerifier;
          }
          /**
           * @notice Lock original tokens to trigger cross-chain mint of pegged tokens at a remote chain's PeggedTokenBridge.
           * NOTE: This function DOES NOT SUPPORT fee-on-transfer / rebasing tokens.
           * @param _token The original token address.
           * @param _amount The amount to deposit.
           * @param _mintChainId The destination chain ID to mint tokens.
           * @param _mintAccount The destination account to receive the minted pegged tokens.
           * @param _nonce A number input to guarantee unique depositId. Can be timestamp in practice.
           */
          function deposit(
              address _token,
              uint256 _amount,
              uint64 _mintChainId,
              address _mintAccount,
              uint64 _nonce
          ) external nonReentrant whenNotPaused returns (bytes32) {
              bytes32 depId = _deposit(_token, _amount, _mintChainId, _mintAccount, _nonce);
              IERC20(_token).safeTransferFrom(msg.sender, address(this), _amount);
              emit Deposited(depId, msg.sender, _token, _amount, _mintChainId, _mintAccount, _nonce);
              return depId;
          }
          /**
           * @notice Lock native token as original token to trigger cross-chain mint of pegged tokens at a remote chain's
           * PeggedTokenBridge.
           * @param _amount The amount to deposit.
           * @param _mintChainId The destination chain ID to mint tokens.
           * @param _mintAccount The destination account to receive the minted pegged tokens.
           * @param _nonce A number input to guarantee unique depositId. Can be timestamp in practice.
           */
          function depositNative(
              uint256 _amount,
              uint64 _mintChainId,
              address _mintAccount,
              uint64 _nonce
          ) external payable nonReentrant whenNotPaused returns (bytes32) {
              require(msg.value == _amount, "Amount mismatch");
              require(nativeWrap != address(0), "Native wrap not set");
              bytes32 depId = _deposit(nativeWrap, _amount, _mintChainId, _mintAccount, _nonce);
              IWETH(nativeWrap).deposit{value: _amount}();
              emit Deposited(depId, msg.sender, nativeWrap, _amount, _mintChainId, _mintAccount, _nonce);
              return depId;
          }
          function _deposit(
              address _token,
              uint256 _amount,
              uint64 _mintChainId,
              address _mintAccount,
              uint64 _nonce
          ) private returns (bytes32) {
              require(_amount > minDeposit[_token], "amount too small");
              require(maxDeposit[_token] == 0 || _amount <= maxDeposit[_token], "amount too large");
              bytes32 depId = keccak256(
                  // len = 20 + 20 + 32 + 8 + 20 + 8 + 8 + 20 = 136
                  abi.encodePacked(
                      msg.sender,
                      _token,
                      _amount,
                      _mintChainId,
                      _mintAccount,
                      _nonce,
                      uint64(block.chainid),
                      address(this)
                  )
              );
              require(records[depId] == false, "record exists");
              records[depId] = true;
              return depId;
          }
          /**
           * @notice Withdraw locked original tokens triggered by a burn at a remote chain's PeggedTokenBridge.
           * @param _request The serialized Withdraw protobuf.
           * @param _sigs The list of signatures sorted by signing addresses in ascending order. A relay must be signed-off by
           * +2/3 of the bridge's current signing power to be delivered.
           * @param _signers The sorted list of signers.
           * @param _powers The signing powers of the signers.
           */
          function withdraw(
              bytes calldata _request,
              bytes[] calldata _sigs,
              address[] calldata _signers,
              uint256[] calldata _powers
          ) external whenNotPaused returns (bytes32) {
              bytes32 domain = keccak256(abi.encodePacked(block.chainid, address(this), "Withdraw"));
              sigsVerifier.verifySigs(abi.encodePacked(domain, _request), _sigs, _signers, _powers);
              PbPegged.Withdraw memory request = PbPegged.decWithdraw(_request);
              bytes32 wdId = keccak256(
                  // len = 20 + 20 + 32 + 20 + 8 + 32 + 20 = 152
                  abi.encodePacked(
                      request.receiver,
                      request.token,
                      request.amount,
                      request.burnAccount,
                      request.refChainId,
                      request.refId,
                      address(this)
                  )
              );
              require(records[wdId] == false, "record exists");
              records[wdId] = true;
              _updateVolume(request.token, request.amount);
              uint256 delayThreshold = delayThresholds[request.token];
              if (delayThreshold > 0 && request.amount > delayThreshold) {
                  _addDelayedTransfer(wdId, request.receiver, request.token, request.amount);
              } else {
                  _sendToken(request.receiver, request.token, request.amount);
              }
              emit Withdrawn(
                  wdId,
                  request.receiver,
                  request.token,
                  request.amount,
                  request.refChainId,
                  request.refId,
                  request.burnAccount
              );
              return wdId;
          }
          function executeDelayedTransfer(bytes32 id) external whenNotPaused {
              delayedTransfer memory transfer = _executeDelayedTransfer(id);
              _sendToken(transfer.receiver, transfer.token, transfer.amount);
          }
          function setMinDeposit(address[] calldata _tokens, uint256[] calldata _amounts) external onlyGovernor {
              require(_tokens.length == _amounts.length, "length mismatch");
              for (uint256 i = 0; i < _tokens.length; i++) {
                  minDeposit[_tokens[i]] = _amounts[i];
                  emit MinDepositUpdated(_tokens[i], _amounts[i]);
              }
          }
          function setMaxDeposit(address[] calldata _tokens, uint256[] calldata _amounts) external onlyGovernor {
              require(_tokens.length == _amounts.length, "length mismatch");
              for (uint256 i = 0; i < _tokens.length; i++) {
                  maxDeposit[_tokens[i]] = _amounts[i];
                  emit MaxDepositUpdated(_tokens[i], _amounts[i]);
              }
          }
          function setWrap(address _weth) external onlyOwner {
              nativeWrap = _weth;
          }
          function _sendToken(
              address _receiver,
              address _token,
              uint256 _amount
          ) private {
              if (_token == nativeWrap) {
                  // withdraw then transfer native to receiver
                  IWETH(nativeWrap).withdraw(_amount);
                  (bool sent, ) = _receiver.call{value: _amount, gas: 50000}("");
                  require(sent, "failed to send native token");
              } else {
                  IERC20(_token).safeTransfer(_receiver, _amount);
              }
          }
          receive() external payable {}
      }
      // SPDX-License-Identifier: MIT
      // OpenZeppelin Contracts (last updated v4.5.0) (token/ERC20/IERC20.sol)
      pragma solidity ^0.8.0;
      /**
       * @dev Interface of the ERC20 standard as defined in the EIP.
       */
      interface IERC20 {
          /**
           * @dev Returns the amount of tokens in existence.
           */
          function totalSupply() external view returns (uint256);
          /**
           * @dev Returns the amount of tokens owned by `account`.
           */
          function balanceOf(address account) external view returns (uint256);
          /**
           * @dev Moves `amount` tokens from the caller's account to `to`.
           *
           * Returns a boolean value indicating whether the operation succeeded.
           *
           * Emits a {Transfer} event.
           */
          function transfer(address to, uint256 amount) external returns (bool);
          /**
           * @dev Returns the remaining number of tokens that `spender` will be
           * allowed to spend on behalf of `owner` through {transferFrom}. This is
           * zero by default.
           *
           * This value changes when {approve} or {transferFrom} are called.
           */
          function allowance(address owner, address spender) external view returns (uint256);
          /**
           * @dev Sets `amount` as the allowance of `spender` over the caller's tokens.
           *
           * Returns a boolean value indicating whether the operation succeeded.
           *
           * IMPORTANT: Beware that changing an allowance with this method brings the risk
           * that someone may use both the old and the new allowance by unfortunate
           * transaction ordering. One possible solution to mitigate this race
           * condition is to first reduce the spender's allowance to 0 and set the
           * desired value afterwards:
           * https://github.com/ethereum/EIPs/issues/20#issuecomment-263524729
           *
           * Emits an {Approval} event.
           */
          function approve(address spender, uint256 amount) external returns (bool);
          /**
           * @dev Moves `amount` tokens from `from` to `to` using the
           * allowance mechanism. `amount` is then deducted from the caller's
           * allowance.
           *
           * Returns a boolean value indicating whether the operation succeeded.
           *
           * Emits a {Transfer} event.
           */
          function transferFrom(
              address from,
              address to,
              uint256 amount
          ) external returns (bool);
          /**
           * @dev Emitted when `value` tokens are moved from one account (`from`) to
           * another (`to`).
           *
           * Note that `value` may be zero.
           */
          event Transfer(address indexed from, address indexed to, uint256 value);
          /**
           * @dev Emitted when the allowance of a `spender` for an `owner` is set by
           * a call to {approve}. `value` is the new allowance.
           */
          event Approval(address indexed owner, address indexed spender, uint256 value);
      }
      // SPDX-License-Identifier: MIT
      // OpenZeppelin Contracts v4.4.1 (token/ERC20/utils/SafeERC20.sol)
      pragma solidity ^0.8.0;
      import "../IERC20.sol";
      import "../../../utils/Address.sol";
      /**
       * @title SafeERC20
       * @dev Wrappers around ERC20 operations that throw on failure (when the token
       * contract returns false). Tokens that return no value (and instead revert or
       * throw on failure) are also supported, non-reverting calls are assumed to be
       * successful.
       * To use this library you can add a `using SafeERC20 for IERC20;` statement to your contract,
       * which allows you to call the safe operations as `token.safeTransfer(...)`, etc.
       */
      library SafeERC20 {
          using Address for address;
          function safeTransfer(
              IERC20 token,
              address to,
              uint256 value
          ) internal {
              _callOptionalReturn(token, abi.encodeWithSelector(token.transfer.selector, to, value));
          }
          function safeTransferFrom(
              IERC20 token,
              address from,
              address to,
              uint256 value
          ) internal {
              _callOptionalReturn(token, abi.encodeWithSelector(token.transferFrom.selector, from, to, value));
          }
          /**
           * @dev Deprecated. This function has issues similar to the ones found in
           * {IERC20-approve}, and its usage is discouraged.
           *
           * Whenever possible, use {safeIncreaseAllowance} and
           * {safeDecreaseAllowance} instead.
           */
          function safeApprove(
              IERC20 token,
              address spender,
              uint256 value
          ) internal {
              // safeApprove should only be called when setting an initial allowance,
              // or when resetting it to zero. To increase and decrease it, use
              // 'safeIncreaseAllowance' and 'safeDecreaseAllowance'
              require(
                  (value == 0) || (token.allowance(address(this), spender) == 0),
                  "SafeERC20: approve from non-zero to non-zero allowance"
              );
              _callOptionalReturn(token, abi.encodeWithSelector(token.approve.selector, spender, value));
          }
          function safeIncreaseAllowance(
              IERC20 token,
              address spender,
              uint256 value
          ) internal {
              uint256 newAllowance = token.allowance(address(this), spender) + value;
              _callOptionalReturn(token, abi.encodeWithSelector(token.approve.selector, spender, newAllowance));
          }
          function safeDecreaseAllowance(
              IERC20 token,
              address spender,
              uint256 value
          ) internal {
              unchecked {
                  uint256 oldAllowance = token.allowance(address(this), spender);
                  require(oldAllowance >= value, "SafeERC20: decreased allowance below zero");
                  uint256 newAllowance = oldAllowance - value;
                  _callOptionalReturn(token, abi.encodeWithSelector(token.approve.selector, spender, newAllowance));
              }
          }
          /**
           * @dev Imitates a Solidity high-level call (i.e. a regular function call to a contract), relaxing the requirement
           * on the return value: the return value is optional (but if data is returned, it must not be false).
           * @param token The token targeted by the call.
           * @param data The call data (encoded using abi.encode or one of its variants).
           */
          function _callOptionalReturn(IERC20 token, bytes memory data) private {
              // We need to perform a low level call here, to bypass Solidity's return data size checking mechanism, since
              // we're implementing it ourselves. We use {Address.functionCall} to perform this call, which verifies that
              // the target address contains contract code and also asserts for success in the low-level call.
              bytes memory returndata = address(token).functionCall(data, "SafeERC20: low-level call failed");
              if (returndata.length > 0) {
                  // Return data is optional
                  require(abi.decode(returndata, (bool)), "SafeERC20: ERC20 operation did not succeed");
              }
          }
      }
      // SPDX-License-Identifier: MIT
      // OpenZeppelin Contracts v4.4.1 (security/ReentrancyGuard.sol)
      pragma solidity ^0.8.0;
      /**
       * @dev Contract module that helps prevent reentrant calls to a function.
       *
       * Inheriting from `ReentrancyGuard` will make the {nonReentrant} modifier
       * available, which can be applied to functions to make sure there are no nested
       * (reentrant) calls to them.
       *
       * Note that because there is a single `nonReentrant` guard, functions marked as
       * `nonReentrant` may not call one another. This can be worked around by making
       * those functions `private`, and then adding `external` `nonReentrant` entry
       * points to them.
       *
       * TIP: If you would like to learn more about reentrancy and alternative ways
       * to protect against it, check out our blog post
       * https://blog.openzeppelin.com/reentrancy-after-istanbul/[Reentrancy After Istanbul].
       */
      abstract contract ReentrancyGuard {
          // Booleans are more expensive than uint256 or any type that takes up a full
          // word because each write operation emits an extra SLOAD to first read the
          // slot's contents, replace the bits taken up by the boolean, and then write
          // back. This is the compiler's defense against contract upgrades and
          // pointer aliasing, and it cannot be disabled.
          // The values being non-zero value makes deployment a bit more expensive,
          // but in exchange the refund on every call to nonReentrant will be lower in
          // amount. Since refunds are capped to a percentage of the total
          // transaction's gas, it is best to keep them low in cases like this one, to
          // increase the likelihood of the full refund coming into effect.
          uint256 private constant _NOT_ENTERED = 1;
          uint256 private constant _ENTERED = 2;
          uint256 private _status;
          constructor() {
              _status = _NOT_ENTERED;
          }
          /**
           * @dev Prevents a contract from calling itself, directly or indirectly.
           * Calling a `nonReentrant` function from another `nonReentrant`
           * function is not supported. It is possible to prevent this from happening
           * by making the `nonReentrant` function external, and making it call a
           * `private` function that does the actual work.
           */
          modifier nonReentrant() {
              // On the first call to nonReentrant, _notEntered will be true
              require(_status != _ENTERED, "ReentrancyGuard: reentrant call");
              // Any calls to nonReentrant after this point will fail
              _status = _ENTERED;
              _;
              // By storing the original value once again, a refund is triggered (see
              // https://eips.ethereum.org/EIPS/eip-2200)
              _status = _NOT_ENTERED;
          }
      }
      // SPDX-License-Identifier: GPL-3.0-only
      pragma solidity >=0.8.0;
      interface ISigsVerifier {
          /**
           * @notice Verifies that a message is signed by a quorum among the signers.
           * @param _msg signed message
           * @param _sigs list of signatures sorted by signer addresses in ascending order
           * @param _signers sorted list of current signers
           * @param _powers powers of current signers
           */
          function verifySigs(
              bytes memory _msg,
              bytes[] calldata _sigs,
              address[] calldata _signers,
              uint256[] calldata _powers
          ) external view;
      }
      // SPDX-License-Identifier: GPL-3.0-only
      pragma solidity >=0.8.0;
      interface IWETH {
          function deposit() external payable;
          function withdraw(uint256) external;
      }
      // SPDX-License-Identifier: GPL-3.0-only
      // Code generated by protoc-gen-sol. DO NOT EDIT.
      // source: contracts/libraries/proto/pegged.proto
      pragma solidity 0.8.9;
      import "./Pb.sol";
      library PbPegged {
          using Pb for Pb.Buffer; // so we can call Pb funcs on Buffer obj
          struct Mint {
              address token; // tag: 1
              address account; // tag: 2
              uint256 amount; // tag: 3
              address depositor; // tag: 4
              uint64 refChainId; // tag: 5
              bytes32 refId; // tag: 6
          } // end struct Mint
          function decMint(bytes memory raw) internal pure returns (Mint memory m) {
              Pb.Buffer memory buf = Pb.fromBytes(raw);
              uint256 tag;
              Pb.WireType wire;
              while (buf.hasMore()) {
                  (tag, wire) = buf.decKey();
                  if (false) {}
                  // solidity has no switch/case
                  else if (tag == 1) {
                      m.token = Pb._address(buf.decBytes());
                  } else if (tag == 2) {
                      m.account = Pb._address(buf.decBytes());
                  } else if (tag == 3) {
                      m.amount = Pb._uint256(buf.decBytes());
                  } else if (tag == 4) {
                      m.depositor = Pb._address(buf.decBytes());
                  } else if (tag == 5) {
                      m.refChainId = uint64(buf.decVarint());
                  } else if (tag == 6) {
                      m.refId = Pb._bytes32(buf.decBytes());
                  } else {
                      buf.skipValue(wire);
                  } // skip value of unknown tag
              }
          } // end decoder Mint
          struct Withdraw {
              address token; // tag: 1
              address receiver; // tag: 2
              uint256 amount; // tag: 3
              address burnAccount; // tag: 4
              uint64 refChainId; // tag: 5
              bytes32 refId; // tag: 6
          } // end struct Withdraw
          function decWithdraw(bytes memory raw) internal pure returns (Withdraw memory m) {
              Pb.Buffer memory buf = Pb.fromBytes(raw);
              uint256 tag;
              Pb.WireType wire;
              while (buf.hasMore()) {
                  (tag, wire) = buf.decKey();
                  if (false) {}
                  // solidity has no switch/case
                  else if (tag == 1) {
                      m.token = Pb._address(buf.decBytes());
                  } else if (tag == 2) {
                      m.receiver = Pb._address(buf.decBytes());
                  } else if (tag == 3) {
                      m.amount = Pb._uint256(buf.decBytes());
                  } else if (tag == 4) {
                      m.burnAccount = Pb._address(buf.decBytes());
                  } else if (tag == 5) {
                      m.refChainId = uint64(buf.decVarint());
                  } else if (tag == 6) {
                      m.refId = Pb._bytes32(buf.decBytes());
                  } else {
                      buf.skipValue(wire);
                  } // skip value of unknown tag
              }
          } // end decoder Withdraw
      }
      // SPDX-License-Identifier: GPL-3.0-only
      pragma solidity 0.8.9;
      import "@openzeppelin/contracts/security/Pausable.sol";
      import "./Ownable.sol";
      abstract contract Pauser is Ownable, Pausable {
          mapping(address => bool) public pausers;
          event PauserAdded(address account);
          event PauserRemoved(address account);
          constructor() {
              _addPauser(msg.sender);
          }
          modifier onlyPauser() {
              require(isPauser(msg.sender), "Caller is not pauser");
              _;
          }
          function pause() public onlyPauser {
              _pause();
          }
          function unpause() public onlyPauser {
              _unpause();
          }
          function isPauser(address account) public view returns (bool) {
              return pausers[account];
          }
          function addPauser(address account) public onlyOwner {
              _addPauser(account);
          }
          function removePauser(address account) public onlyOwner {
              _removePauser(account);
          }
          function renouncePauser() public {
              _removePauser(msg.sender);
          }
          function _addPauser(address account) private {
              require(!isPauser(account), "Account is already pauser");
              pausers[account] = true;
              emit PauserAdded(account);
          }
          function _removePauser(address account) private {
              require(isPauser(account), "Account is not pauser");
              pausers[account] = false;
              emit PauserRemoved(account);
          }
      }
      // SPDX-License-Identifier: GPL-3.0-only
      pragma solidity 0.8.9;
      import "./Governor.sol";
      abstract contract VolumeControl is Governor {
          uint256 public epochLength; // seconds
          mapping(address => uint256) public epochVolumes; // key is token
          mapping(address => uint256) public epochVolumeCaps; // key is token
          mapping(address => uint256) public lastOpTimestamps; // key is token
          event EpochLengthUpdated(uint256 length);
          event EpochVolumeUpdated(address token, uint256 cap);
          function setEpochLength(uint256 _length) external onlyGovernor {
              epochLength = _length;
              emit EpochLengthUpdated(_length);
          }
          function setEpochVolumeCaps(address[] calldata _tokens, uint256[] calldata _caps) external onlyGovernor {
              require(_tokens.length == _caps.length, "length mismatch");
              for (uint256 i = 0; i < _tokens.length; i++) {
                  epochVolumeCaps[_tokens[i]] = _caps[i];
                  emit EpochVolumeUpdated(_tokens[i], _caps[i]);
              }
          }
          function _updateVolume(address _token, uint256 _amount) internal {
              if (epochLength == 0) {
                  return;
              }
              uint256 cap = epochVolumeCaps[_token];
              if (cap == 0) {
                  return;
              }
              uint256 volume = epochVolumes[_token];
              uint256 timestamp = block.timestamp;
              uint256 epochStartTime = (timestamp / epochLength) * epochLength;
              if (lastOpTimestamps[_token] < epochStartTime) {
                  volume = _amount;
              } else {
                  volume += _amount;
              }
              require(volume <= cap, "volume exceeds cap");
              epochVolumes[_token] = volume;
              lastOpTimestamps[_token] = timestamp;
          }
      }
      // SPDX-License-Identifier: GPL-3.0-only
      pragma solidity 0.8.9;
      import "./Governor.sol";
      abstract contract DelayedTransfer is Governor {
          struct delayedTransfer {
              address receiver;
              address token;
              uint256 amount;
              uint256 timestamp;
          }
          mapping(bytes32 => delayedTransfer) public delayedTransfers;
          mapping(address => uint256) public delayThresholds;
          uint256 public delayPeriod; // in seconds
          event DelayedTransferAdded(bytes32 id);
          event DelayedTransferExecuted(bytes32 id, address receiver, address token, uint256 amount);
          event DelayPeriodUpdated(uint256 period);
          event DelayThresholdUpdated(address token, uint256 threshold);
          function setDelayThresholds(address[] calldata _tokens, uint256[] calldata _thresholds) external onlyGovernor {
              require(_tokens.length == _thresholds.length, "length mismatch");
              for (uint256 i = 0; i < _tokens.length; i++) {
                  delayThresholds[_tokens[i]] = _thresholds[i];
                  emit DelayThresholdUpdated(_tokens[i], _thresholds[i]);
              }
          }
          function setDelayPeriod(uint256 _period) external onlyGovernor {
              delayPeriod = _period;
              emit DelayPeriodUpdated(_period);
          }
          function _addDelayedTransfer(
              bytes32 id,
              address receiver,
              address token,
              uint256 amount
          ) internal {
              require(delayedTransfers[id].timestamp == 0, "delayed transfer already exists");
              delayedTransfers[id] = delayedTransfer({
                  receiver: receiver,
                  token: token,
                  amount: amount,
                  timestamp: block.timestamp
              });
              emit DelayedTransferAdded(id);
          }
          // caller needs to do the actual token transfer
          function _executeDelayedTransfer(bytes32 id) internal returns (delayedTransfer memory) {
              delayedTransfer memory transfer = delayedTransfers[id];
              require(transfer.timestamp > 0, "delayed transfer not exist");
              require(block.timestamp > transfer.timestamp + delayPeriod, "delayed transfer still locked");
              delete delayedTransfers[id];
              emit DelayedTransferExecuted(id, transfer.receiver, transfer.token, transfer.amount);
              return transfer;
          }
      }
      // SPDX-License-Identifier: MIT
      // OpenZeppelin Contracts (last updated v4.5.0) (utils/Address.sol)
      pragma solidity ^0.8.1;
      /**
       * @dev Collection of functions related to the address type
       */
      library Address {
          /**
           * @dev Returns true if `account` is a contract.
           *
           * [IMPORTANT]
           * ====
           * It is unsafe to assume that an address for which this function returns
           * false is an externally-owned account (EOA) and not a contract.
           *
           * Among others, `isContract` will return false for the following
           * types of addresses:
           *
           *  - an externally-owned account
           *  - a contract in construction
           *  - an address where a contract will be created
           *  - an address where a contract lived, but was destroyed
           * ====
           *
           * [IMPORTANT]
           * ====
           * You shouldn't rely on `isContract` to protect against flash loan attacks!
           *
           * Preventing calls from contracts is highly discouraged. It breaks composability, breaks support for smart wallets
           * like Gnosis Safe, and does not provide security since it can be circumvented by calling from a contract
           * constructor.
           * ====
           */
          function isContract(address account) internal view returns (bool) {
              // This method relies on extcodesize/address.code.length, which returns 0
              // for contracts in construction, since the code is only stored at the end
              // of the constructor execution.
              return account.code.length > 0;
          }
          /**
           * @dev Replacement for Solidity's `transfer`: sends `amount` wei to
           * `recipient`, forwarding all available gas and reverting on errors.
           *
           * https://eips.ethereum.org/EIPS/eip-1884[EIP1884] increases the gas cost
           * of certain opcodes, possibly making contracts go over the 2300 gas limit
           * imposed by `transfer`, making them unable to receive funds via
           * `transfer`. {sendValue} removes this limitation.
           *
           * https://diligence.consensys.net/posts/2019/09/stop-using-soliditys-transfer-now/[Learn more].
           *
           * IMPORTANT: because control is transferred to `recipient`, care must be
           * taken to not create reentrancy vulnerabilities. Consider using
           * {ReentrancyGuard} or the
           * https://solidity.readthedocs.io/en/v0.5.11/security-considerations.html#use-the-checks-effects-interactions-pattern[checks-effects-interactions pattern].
           */
          function sendValue(address payable recipient, uint256 amount) internal {
              require(address(this).balance >= amount, "Address: insufficient balance");
              (bool success, ) = recipient.call{value: amount}("");
              require(success, "Address: unable to send value, recipient may have reverted");
          }
          /**
           * @dev Performs a Solidity function call using a low level `call`. A
           * plain `call` is an unsafe replacement for a function call: use this
           * function instead.
           *
           * If `target` reverts with a revert reason, it is bubbled up by this
           * function (like regular Solidity function calls).
           *
           * Returns the raw returned data. To convert to the expected return value,
           * use https://solidity.readthedocs.io/en/latest/units-and-global-variables.html?highlight=abi.decode#abi-encoding-and-decoding-functions[`abi.decode`].
           *
           * Requirements:
           *
           * - `target` must be a contract.
           * - calling `target` with `data` must not revert.
           *
           * _Available since v3.1._
           */
          function functionCall(address target, bytes memory data) internal returns (bytes memory) {
              return functionCall(target, data, "Address: low-level call failed");
          }
          /**
           * @dev Same as {xref-Address-functionCall-address-bytes-}[`functionCall`], but with
           * `errorMessage` as a fallback revert reason when `target` reverts.
           *
           * _Available since v3.1._
           */
          function functionCall(
              address target,
              bytes memory data,
              string memory errorMessage
          ) internal returns (bytes memory) {
              return functionCallWithValue(target, data, 0, errorMessage);
          }
          /**
           * @dev Same as {xref-Address-functionCall-address-bytes-}[`functionCall`],
           * but also transferring `value` wei to `target`.
           *
           * Requirements:
           *
           * - the calling contract must have an ETH balance of at least `value`.
           * - the called Solidity function must be `payable`.
           *
           * _Available since v3.1._
           */
          function functionCallWithValue(
              address target,
              bytes memory data,
              uint256 value
          ) internal returns (bytes memory) {
              return functionCallWithValue(target, data, value, "Address: low-level call with value failed");
          }
          /**
           * @dev Same as {xref-Address-functionCallWithValue-address-bytes-uint256-}[`functionCallWithValue`], but
           * with `errorMessage` as a fallback revert reason when `target` reverts.
           *
           * _Available since v3.1._
           */
          function functionCallWithValue(
              address target,
              bytes memory data,
              uint256 value,
              string memory errorMessage
          ) internal returns (bytes memory) {
              require(address(this).balance >= value, "Address: insufficient balance for call");
              require(isContract(target), "Address: call to non-contract");
              (bool success, bytes memory returndata) = target.call{value: value}(data);
              return verifyCallResult(success, returndata, errorMessage);
          }
          /**
           * @dev Same as {xref-Address-functionCall-address-bytes-}[`functionCall`],
           * but performing a static call.
           *
           * _Available since v3.3._
           */
          function functionStaticCall(address target, bytes memory data) internal view returns (bytes memory) {
              return functionStaticCall(target, data, "Address: low-level static call failed");
          }
          /**
           * @dev Same as {xref-Address-functionCall-address-bytes-string-}[`functionCall`],
           * but performing a static call.
           *
           * _Available since v3.3._
           */
          function functionStaticCall(
              address target,
              bytes memory data,
              string memory errorMessage
          ) internal view returns (bytes memory) {
              require(isContract(target), "Address: static call to non-contract");
              (bool success, bytes memory returndata) = target.staticcall(data);
              return verifyCallResult(success, returndata, errorMessage);
          }
          /**
           * @dev Same as {xref-Address-functionCall-address-bytes-}[`functionCall`],
           * but performing a delegate call.
           *
           * _Available since v3.4._
           */
          function functionDelegateCall(address target, bytes memory data) internal returns (bytes memory) {
              return functionDelegateCall(target, data, "Address: low-level delegate call failed");
          }
          /**
           * @dev Same as {xref-Address-functionCall-address-bytes-string-}[`functionCall`],
           * but performing a delegate call.
           *
           * _Available since v3.4._
           */
          function functionDelegateCall(
              address target,
              bytes memory data,
              string memory errorMessage
          ) internal returns (bytes memory) {
              require(isContract(target), "Address: delegate call to non-contract");
              (bool success, bytes memory returndata) = target.delegatecall(data);
              return verifyCallResult(success, returndata, errorMessage);
          }
          /**
           * @dev Tool to verifies that a low level call was successful, and revert if it wasn't, either by bubbling the
           * revert reason using the provided one.
           *
           * _Available since v4.3._
           */
          function verifyCallResult(
              bool success,
              bytes memory returndata,
              string memory errorMessage
          ) internal pure returns (bytes memory) {
              if (success) {
                  return returndata;
              } else {
                  // Look for revert reason and bubble it up if present
                  if (returndata.length > 0) {
                      // The easiest way to bubble the revert reason is using memory via assembly
                      assembly {
                          let returndata_size := mload(returndata)
                          revert(add(32, returndata), returndata_size)
                      }
                  } else {
                      revert(errorMessage);
                  }
              }
          }
      }
      // SPDX-License-Identifier: GPL-3.0-only
      pragma solidity 0.8.9;
      // runtime proto sol library
      library Pb {
          enum WireType {
              Varint,
              Fixed64,
              LengthDelim,
              StartGroup,
              EndGroup,
              Fixed32
          }
          struct Buffer {
              uint256 idx; // the start index of next read. when idx=b.length, we're done
              bytes b; // hold serialized proto msg, readonly
          }
          // create a new in-memory Buffer object from raw msg bytes
          function fromBytes(bytes memory raw) internal pure returns (Buffer memory buf) {
              buf.b = raw;
              buf.idx = 0;
          }
          // whether there are unread bytes
          function hasMore(Buffer memory buf) internal pure returns (bool) {
              return buf.idx < buf.b.length;
          }
          // decode current field number and wiretype
          function decKey(Buffer memory buf) internal pure returns (uint256 tag, WireType wiretype) {
              uint256 v = decVarint(buf);
              tag = v / 8;
              wiretype = WireType(v & 7);
          }
          // count tag occurrences, return an array due to no memory map support
          // have to create array for (maxtag+1) size. cnts[tag] = occurrences
          // should keep buf.idx unchanged because this is only a count function
          function cntTags(Buffer memory buf, uint256 maxtag) internal pure returns (uint256[] memory cnts) {
              uint256 originalIdx = buf.idx;
              cnts = new uint256[](maxtag + 1); // protobuf's tags are from 1 rather than 0
              uint256 tag;
              WireType wire;
              while (hasMore(buf)) {
                  (tag, wire) = decKey(buf);
                  cnts[tag] += 1;
                  skipValue(buf, wire);
              }
              buf.idx = originalIdx;
          }
          // read varint from current buf idx, move buf.idx to next read, return the int value
          function decVarint(Buffer memory buf) internal pure returns (uint256 v) {
              bytes10 tmp; // proto int is at most 10 bytes (7 bits can be used per byte)
              bytes memory bb = buf.b; // get buf.b mem addr to use in assembly
              v = buf.idx; // use v to save one additional uint variable
              assembly {
                  tmp := mload(add(add(bb, 32), v)) // load 10 bytes from buf.b[buf.idx] to tmp
              }
              uint256 b; // store current byte content
              v = 0; // reset to 0 for return value
              for (uint256 i = 0; i < 10; i++) {
                  assembly {
                      b := byte(i, tmp) // don't use tmp[i] because it does bound check and costs extra
                  }
                  v |= (b & 0x7F) << (i * 7);
                  if (b & 0x80 == 0) {
                      buf.idx += i + 1;
                      return v;
                  }
              }
              revert(); // i=10, invalid varint stream
          }
          // read length delimited field and return bytes
          function decBytes(Buffer memory buf) internal pure returns (bytes memory b) {
              uint256 len = decVarint(buf);
              uint256 end = buf.idx + len;
              require(end <= buf.b.length); // avoid overflow
              b = new bytes(len);
              bytes memory bufB = buf.b; // get buf.b mem addr to use in assembly
              uint256 bStart;
              uint256 bufBStart = buf.idx;
              assembly {
                  bStart := add(b, 32)
                  bufBStart := add(add(bufB, 32), bufBStart)
              }
              for (uint256 i = 0; i < len; i += 32) {
                  assembly {
                      mstore(add(bStart, i), mload(add(bufBStart, i)))
                  }
              }
              buf.idx = end;
          }
          // return packed ints
          function decPacked(Buffer memory buf) internal pure returns (uint256[] memory t) {
              uint256 len = decVarint(buf);
              uint256 end = buf.idx + len;
              require(end <= buf.b.length); // avoid overflow
              // array in memory must be init w/ known length
              // so we have to create a tmp array w/ max possible len first
              uint256[] memory tmp = new uint256[](len);
              uint256 i = 0; // count how many ints are there
              while (buf.idx < end) {
                  tmp[i] = decVarint(buf);
                  i++;
              }
              t = new uint256[](i); // init t with correct length
              for (uint256 j = 0; j < i; j++) {
                  t[j] = tmp[j];
              }
              return t;
          }
          // move idx pass current value field, to beginning of next tag or msg end
          function skipValue(Buffer memory buf, WireType wire) internal pure {
              if (wire == WireType.Varint) {
                  decVarint(buf);
              } else if (wire == WireType.LengthDelim) {
                  uint256 len = decVarint(buf);
                  buf.idx += len; // skip len bytes value data
                  require(buf.idx <= buf.b.length); // avoid overflow
              } else {
                  revert();
              } // unsupported wiretype
          }
          // type conversion help utils
          function _bool(uint256 x) internal pure returns (bool v) {
              return x != 0;
          }
          function _uint256(bytes memory b) internal pure returns (uint256 v) {
              require(b.length <= 32); // b's length must be smaller than or equal to 32
              assembly {
                  v := mload(add(b, 32))
              } // load all 32bytes to v
              v = v >> (8 * (32 - b.length)); // only first b.length is valid
          }
          function _address(bytes memory b) internal pure returns (address v) {
              v = _addressPayable(b);
          }
          function _addressPayable(bytes memory b) internal pure returns (address payable v) {
              require(b.length == 20);
              //load 32bytes then shift right 12 bytes
              assembly {
                  v := div(mload(add(b, 32)), 0x1000000000000000000000000)
              }
          }
          function _bytes32(bytes memory b) internal pure returns (bytes32 v) {
              require(b.length == 32);
              assembly {
                  v := mload(add(b, 32))
              }
          }
          // uint[] to uint8[]
          function uint8s(uint256[] memory arr) internal pure returns (uint8[] memory t) {
              t = new uint8[](arr.length);
              for (uint256 i = 0; i < t.length; i++) {
                  t[i] = uint8(arr[i]);
              }
          }
          function uint32s(uint256[] memory arr) internal pure returns (uint32[] memory t) {
              t = new uint32[](arr.length);
              for (uint256 i = 0; i < t.length; i++) {
                  t[i] = uint32(arr[i]);
              }
          }
          function uint64s(uint256[] memory arr) internal pure returns (uint64[] memory t) {
              t = new uint64[](arr.length);
              for (uint256 i = 0; i < t.length; i++) {
                  t[i] = uint64(arr[i]);
              }
          }
          function bools(uint256[] memory arr) internal pure returns (bool[] memory t) {
              t = new bool[](arr.length);
              for (uint256 i = 0; i < t.length; i++) {
                  t[i] = arr[i] != 0;
              }
          }
      }
      // SPDX-License-Identifier: MIT
      // OpenZeppelin Contracts v4.4.1 (security/Pausable.sol)
      pragma solidity ^0.8.0;
      import "../utils/Context.sol";
      /**
       * @dev Contract module which allows children to implement an emergency stop
       * mechanism that can be triggered by an authorized account.
       *
       * This module is used through inheritance. It will make available the
       * modifiers `whenNotPaused` and `whenPaused`, which can be applied to
       * the functions of your contract. Note that they will not be pausable by
       * simply including this module, only once the modifiers are put in place.
       */
      abstract contract Pausable is Context {
          /**
           * @dev Emitted when the pause is triggered by `account`.
           */
          event Paused(address account);
          /**
           * @dev Emitted when the pause is lifted by `account`.
           */
          event Unpaused(address account);
          bool private _paused;
          /**
           * @dev Initializes the contract in unpaused state.
           */
          constructor() {
              _paused = false;
          }
          /**
           * @dev Returns true if the contract is paused, and false otherwise.
           */
          function paused() public view virtual returns (bool) {
              return _paused;
          }
          /**
           * @dev Modifier to make a function callable only when the contract is not paused.
           *
           * Requirements:
           *
           * - The contract must not be paused.
           */
          modifier whenNotPaused() {
              require(!paused(), "Pausable: paused");
              _;
          }
          /**
           * @dev Modifier to make a function callable only when the contract is paused.
           *
           * Requirements:
           *
           * - The contract must be paused.
           */
          modifier whenPaused() {
              require(paused(), "Pausable: not paused");
              _;
          }
          /**
           * @dev Triggers stopped state.
           *
           * Requirements:
           *
           * - The contract must not be paused.
           */
          function _pause() internal virtual whenNotPaused {
              _paused = true;
              emit Paused(_msgSender());
          }
          /**
           * @dev Returns to normal state.
           *
           * Requirements:
           *
           * - The contract must be paused.
           */
          function _unpause() internal virtual whenPaused {
              _paused = false;
              emit Unpaused(_msgSender());
          }
      }
      // SPDX-License-Identifier: GPL-3.0-only
      pragma solidity ^0.8.0;
      /**
       * @dev Contract module which provides a basic access control mechanism, where
       * there is an account (an owner) that can be granted exclusive access to
       * specific functions.
       *
       * By default, the owner account will be the one that deploys the contract. This
       * can later be changed with {transferOwnership}.
       *
       * This module is used through inheritance. It will make available the modifier
       * `onlyOwner`, which can be applied to your functions to restrict their use to
       * the owner.
       *
       * This adds a normal func that setOwner if _owner is address(0). So we can't allow
       * renounceOwnership. So we can support Proxy based upgradable contract
       */
      abstract contract Ownable {
          address private _owner;
          event OwnershipTransferred(address indexed previousOwner, address indexed newOwner);
          /**
           * @dev Initializes the contract setting the deployer as the initial owner.
           */
          constructor() {
              _setOwner(msg.sender);
          }
          /**
           * @dev Only to be called by inherit contracts, in their init func called by Proxy
           * we require _owner == address(0), which is only possible when it's a delegateCall
           * because constructor sets _owner in contract state.
           */
          function initOwner() internal {
              require(_owner == address(0), "owner already set");
              _setOwner(msg.sender);
          }
          /**
           * @dev Returns the address of the current owner.
           */
          function owner() public view virtual returns (address) {
              return _owner;
          }
          /**
           * @dev Throws if called by any account other than the owner.
           */
          modifier onlyOwner() {
              require(owner() == msg.sender, "Ownable: caller is not the owner");
              _;
          }
          /**
           * @dev Transfers ownership of the contract to a new account (`newOwner`).
           * Can only be called by the current owner.
           */
          function transferOwnership(address newOwner) public virtual onlyOwner {
              require(newOwner != address(0), "Ownable: new owner is the zero address");
              _setOwner(newOwner);
          }
          function _setOwner(address newOwner) private {
              address oldOwner = _owner;
              _owner = newOwner;
              emit OwnershipTransferred(oldOwner, newOwner);
          }
      }
      // SPDX-License-Identifier: MIT
      // OpenZeppelin Contracts v4.4.1 (utils/Context.sol)
      pragma solidity ^0.8.0;
      /**
       * @dev Provides information about the current execution context, including the
       * sender of the transaction and its data. While these are generally available
       * via msg.sender and msg.data, they should not be accessed in such a direct
       * manner, since when dealing with meta-transactions the account sending and
       * paying for execution may not be the actual sender (as far as an application
       * is concerned).
       *
       * This contract is only required for intermediate, library-like contracts.
       */
      abstract contract Context {
          function _msgSender() internal view virtual returns (address) {
              return msg.sender;
          }
          function _msgData() internal view virtual returns (bytes calldata) {
              return msg.data;
          }
      }
      // SPDX-License-Identifier: GPL-3.0-only
      pragma solidity 0.8.9;
      import "./Ownable.sol";
      abstract contract Governor is Ownable {
          mapping(address => bool) public governors;
          event GovernorAdded(address account);
          event GovernorRemoved(address account);
          modifier onlyGovernor() {
              require(isGovernor(msg.sender), "Caller is not governor");
              _;
          }
          constructor() {
              _addGovernor(msg.sender);
          }
          function isGovernor(address _account) public view returns (bool) {
              return governors[_account];
          }
          function addGovernor(address _account) public onlyOwner {
              _addGovernor(_account);
          }
          function removeGovernor(address _account) public onlyOwner {
              _removeGovernor(_account);
          }
          function renounceGovernor() public {
              _removeGovernor(msg.sender);
          }
          function _addGovernor(address _account) private {
              require(!isGovernor(_account), "Account is already governor");
              governors[_account] = true;
              emit GovernorAdded(_account);
          }
          function _removeGovernor(address _account) private {
              require(isGovernor(_account), "Account is not governor");
              governors[_account] = false;
              emit GovernorRemoved(_account);
          }
      }
      

      File 2 of 2: Bridge
      // SPDX-License-Identifier: MIT
      pragma solidity ^0.8.0;
      import "../utils/Context.sol";
      /**
       * @dev Contract module which provides a basic access control mechanism, where
       * there is an account (an owner) that can be granted exclusive access to
       * specific functions.
       *
       * By default, the owner account will be the one that deploys the contract. This
       * can later be changed with {transferOwnership}.
       *
       * This module is used through inheritance. It will make available the modifier
       * `onlyOwner`, which can be applied to your functions to restrict their use to
       * the owner.
       */
      abstract contract Ownable is Context {
          address private _owner;
          event OwnershipTransferred(address indexed previousOwner, address indexed newOwner);
          /**
           * @dev Initializes the contract setting the deployer as the initial owner.
           */
          constructor() {
              _setOwner(_msgSender());
          }
          /**
           * @dev Returns the address of the current owner.
           */
          function owner() public view virtual returns (address) {
              return _owner;
          }
          /**
           * @dev Throws if called by any account other than the owner.
           */
          modifier onlyOwner() {
              require(owner() == _msgSender(), "Ownable: caller is not the owner");
              _;
          }
          /**
           * @dev Leaves the contract without owner. It will not be possible to call
           * `onlyOwner` functions anymore. Can only be called by the current owner.
           *
           * NOTE: Renouncing ownership will leave the contract without an owner,
           * thereby removing any functionality that is only available to the owner.
           */
          function renounceOwnership() public virtual onlyOwner {
              _setOwner(address(0));
          }
          /**
           * @dev Transfers ownership of the contract to a new account (`newOwner`).
           * Can only be called by the current owner.
           */
          function transferOwnership(address newOwner) public virtual onlyOwner {
              require(newOwner != address(0), "Ownable: new owner is the zero address");
              _setOwner(newOwner);
          }
          function _setOwner(address newOwner) private {
              address oldOwner = _owner;
              _owner = newOwner;
              emit OwnershipTransferred(oldOwner, newOwner);
          }
      }
      // SPDX-License-Identifier: MIT
      pragma solidity ^0.8.0;
      import "../utils/Context.sol";
      /**
       * @dev Contract module which allows children to implement an emergency stop
       * mechanism that can be triggered by an authorized account.
       *
       * This module is used through inheritance. It will make available the
       * modifiers `whenNotPaused` and `whenPaused`, which can be applied to
       * the functions of your contract. Note that they will not be pausable by
       * simply including this module, only once the modifiers are put in place.
       */
      abstract contract Pausable is Context {
          /**
           * @dev Emitted when the pause is triggered by `account`.
           */
          event Paused(address account);
          /**
           * @dev Emitted when the pause is lifted by `account`.
           */
          event Unpaused(address account);
          bool private _paused;
          /**
           * @dev Initializes the contract in unpaused state.
           */
          constructor() {
              _paused = false;
          }
          /**
           * @dev Returns true if the contract is paused, and false otherwise.
           */
          function paused() public view virtual returns (bool) {
              return _paused;
          }
          /**
           * @dev Modifier to make a function callable only when the contract is not paused.
           *
           * Requirements:
           *
           * - The contract must not be paused.
           */
          modifier whenNotPaused() {
              require(!paused(), "Pausable: paused");
              _;
          }
          /**
           * @dev Modifier to make a function callable only when the contract is paused.
           *
           * Requirements:
           *
           * - The contract must be paused.
           */
          modifier whenPaused() {
              require(paused(), "Pausable: not paused");
              _;
          }
          /**
           * @dev Triggers stopped state.
           *
           * Requirements:
           *
           * - The contract must not be paused.
           */
          function _pause() internal virtual whenNotPaused {
              _paused = true;
              emit Paused(_msgSender());
          }
          /**
           * @dev Returns to normal state.
           *
           * Requirements:
           *
           * - The contract must be paused.
           */
          function _unpause() internal virtual whenPaused {
              _paused = false;
              emit Unpaused(_msgSender());
          }
      }
      // SPDX-License-Identifier: MIT
      pragma solidity ^0.8.0;
      /**
       * @dev Contract module that helps prevent reentrant calls to a function.
       *
       * Inheriting from `ReentrancyGuard` will make the {nonReentrant} modifier
       * available, which can be applied to functions to make sure there are no nested
       * (reentrant) calls to them.
       *
       * Note that because there is a single `nonReentrant` guard, functions marked as
       * `nonReentrant` may not call one another. This can be worked around by making
       * those functions `private`, and then adding `external` `nonReentrant` entry
       * points to them.
       *
       * TIP: If you would like to learn more about reentrancy and alternative ways
       * to protect against it, check out our blog post
       * https://blog.openzeppelin.com/reentrancy-after-istanbul/[Reentrancy After Istanbul].
       */
      abstract contract ReentrancyGuard {
          // Booleans are more expensive than uint256 or any type that takes up a full
          // word because each write operation emits an extra SLOAD to first read the
          // slot's contents, replace the bits taken up by the boolean, and then write
          // back. This is the compiler's defense against contract upgrades and
          // pointer aliasing, and it cannot be disabled.
          // The values being non-zero value makes deployment a bit more expensive,
          // but in exchange the refund on every call to nonReentrant will be lower in
          // amount. Since refunds are capped to a percentage of the total
          // transaction's gas, it is best to keep them low in cases like this one, to
          // increase the likelihood of the full refund coming into effect.
          uint256 private constant _NOT_ENTERED = 1;
          uint256 private constant _ENTERED = 2;
          uint256 private _status;
          constructor() {
              _status = _NOT_ENTERED;
          }
          /**
           * @dev Prevents a contract from calling itself, directly or indirectly.
           * Calling a `nonReentrant` function from another `nonReentrant`
           * function is not supported. It is possible to prevent this from happening
           * by making the `nonReentrant` function external, and make it call a
           * `private` function that does the actual work.
           */
          modifier nonReentrant() {
              // On the first call to nonReentrant, _notEntered will be true
              require(_status != _ENTERED, "ReentrancyGuard: reentrant call");
              // Any calls to nonReentrant after this point will fail
              _status = _ENTERED;
              _;
              // By storing the original value once again, a refund is triggered (see
              // https://eips.ethereum.org/EIPS/eip-2200)
              _status = _NOT_ENTERED;
          }
      }
      // SPDX-License-Identifier: MIT
      pragma solidity ^0.8.0;
      /**
       * @dev Interface of the ERC20 standard as defined in the EIP.
       */
      interface IERC20 {
          /**
           * @dev Returns the amount of tokens in existence.
           */
          function totalSupply() external view returns (uint256);
          /**
           * @dev Returns the amount of tokens owned by `account`.
           */
          function balanceOf(address account) external view returns (uint256);
          /**
           * @dev Moves `amount` tokens from the caller's account to `recipient`.
           *
           * Returns a boolean value indicating whether the operation succeeded.
           *
           * Emits a {Transfer} event.
           */
          function transfer(address recipient, uint256 amount) external returns (bool);
          /**
           * @dev Returns the remaining number of tokens that `spender` will be
           * allowed to spend on behalf of `owner` through {transferFrom}. This is
           * zero by default.
           *
           * This value changes when {approve} or {transferFrom} are called.
           */
          function allowance(address owner, address spender) external view returns (uint256);
          /**
           * @dev Sets `amount` as the allowance of `spender` over the caller's tokens.
           *
           * Returns a boolean value indicating whether the operation succeeded.
           *
           * IMPORTANT: Beware that changing an allowance with this method brings the risk
           * that someone may use both the old and the new allowance by unfortunate
           * transaction ordering. One possible solution to mitigate this race
           * condition is to first reduce the spender's allowance to 0 and set the
           * desired value afterwards:
           * https://github.com/ethereum/EIPs/issues/20#issuecomment-263524729
           *
           * Emits an {Approval} event.
           */
          function approve(address spender, uint256 amount) external returns (bool);
          /**
           * @dev Moves `amount` tokens from `sender` to `recipient` using the
           * allowance mechanism. `amount` is then deducted from the caller's
           * allowance.
           *
           * Returns a boolean value indicating whether the operation succeeded.
           *
           * Emits a {Transfer} event.
           */
          function transferFrom(
              address sender,
              address recipient,
              uint256 amount
          ) external returns (bool);
          /**
           * @dev Emitted when `value` tokens are moved from one account (`from`) to
           * another (`to`).
           *
           * Note that `value` may be zero.
           */
          event Transfer(address indexed from, address indexed to, uint256 value);
          /**
           * @dev Emitted when the allowance of a `spender` for an `owner` is set by
           * a call to {approve}. `value` is the new allowance.
           */
          event Approval(address indexed owner, address indexed spender, uint256 value);
      }
      // SPDX-License-Identifier: MIT
      pragma solidity ^0.8.0;
      import "../IERC20.sol";
      import "../../../utils/Address.sol";
      /**
       * @title SafeERC20
       * @dev Wrappers around ERC20 operations that throw on failure (when the token
       * contract returns false). Tokens that return no value (and instead revert or
       * throw on failure) are also supported, non-reverting calls are assumed to be
       * successful.
       * To use this library you can add a `using SafeERC20 for IERC20;` statement to your contract,
       * which allows you to call the safe operations as `token.safeTransfer(...)`, etc.
       */
      library SafeERC20 {
          using Address for address;
          function safeTransfer(
              IERC20 token,
              address to,
              uint256 value
          ) internal {
              _callOptionalReturn(token, abi.encodeWithSelector(token.transfer.selector, to, value));
          }
          function safeTransferFrom(
              IERC20 token,
              address from,
              address to,
              uint256 value
          ) internal {
              _callOptionalReturn(token, abi.encodeWithSelector(token.transferFrom.selector, from, to, value));
          }
          /**
           * @dev Deprecated. This function has issues similar to the ones found in
           * {IERC20-approve}, and its usage is discouraged.
           *
           * Whenever possible, use {safeIncreaseAllowance} and
           * {safeDecreaseAllowance} instead.
           */
          function safeApprove(
              IERC20 token,
              address spender,
              uint256 value
          ) internal {
              // safeApprove should only be called when setting an initial allowance,
              // or when resetting it to zero. To increase and decrease it, use
              // 'safeIncreaseAllowance' and 'safeDecreaseAllowance'
              require(
                  (value == 0) || (token.allowance(address(this), spender) == 0),
                  "SafeERC20: approve from non-zero to non-zero allowance"
              );
              _callOptionalReturn(token, abi.encodeWithSelector(token.approve.selector, spender, value));
          }
          function safeIncreaseAllowance(
              IERC20 token,
              address spender,
              uint256 value
          ) internal {
              uint256 newAllowance = token.allowance(address(this), spender) + value;
              _callOptionalReturn(token, abi.encodeWithSelector(token.approve.selector, spender, newAllowance));
          }
          function safeDecreaseAllowance(
              IERC20 token,
              address spender,
              uint256 value
          ) internal {
              unchecked {
                  uint256 oldAllowance = token.allowance(address(this), spender);
                  require(oldAllowance >= value, "SafeERC20: decreased allowance below zero");
                  uint256 newAllowance = oldAllowance - value;
                  _callOptionalReturn(token, abi.encodeWithSelector(token.approve.selector, spender, newAllowance));
              }
          }
          /**
           * @dev Imitates a Solidity high-level call (i.e. a regular function call to a contract), relaxing the requirement
           * on the return value: the return value is optional (but if data is returned, it must not be false).
           * @param token The token targeted by the call.
           * @param data The call data (encoded using abi.encode or one of its variants).
           */
          function _callOptionalReturn(IERC20 token, bytes memory data) private {
              // We need to perform a low level call here, to bypass Solidity's return data size checking mechanism, since
              // we're implementing it ourselves. We use {Address.functionCall} to perform this call, which verifies that
              // the target address contains contract code and also asserts for success in the low-level call.
              bytes memory returndata = address(token).functionCall(data, "SafeERC20: low-level call failed");
              if (returndata.length > 0) {
                  // Return data is optional
                  require(abi.decode(returndata, (bool)), "SafeERC20: ERC20 operation did not succeed");
              }
          }
      }
      // SPDX-License-Identifier: MIT
      pragma solidity ^0.8.0;
      /**
       * @dev Collection of functions related to the address type
       */
      library Address {
          /**
           * @dev Returns true if `account` is a contract.
           *
           * [IMPORTANT]
           * ====
           * It is unsafe to assume that an address for which this function returns
           * false is an externally-owned account (EOA) and not a contract.
           *
           * Among others, `isContract` will return false for the following
           * types of addresses:
           *
           *  - an externally-owned account
           *  - a contract in construction
           *  - an address where a contract will be created
           *  - an address where a contract lived, but was destroyed
           * ====
           */
          function isContract(address account) internal view returns (bool) {
              // This method relies on extcodesize, which returns 0 for contracts in
              // construction, since the code is only stored at the end of the
              // constructor execution.
              uint256 size;
              assembly {
                  size := extcodesize(account)
              }
              return size > 0;
          }
          /**
           * @dev Replacement for Solidity's `transfer`: sends `amount` wei to
           * `recipient`, forwarding all available gas and reverting on errors.
           *
           * https://eips.ethereum.org/EIPS/eip-1884[EIP1884] increases the gas cost
           * of certain opcodes, possibly making contracts go over the 2300 gas limit
           * imposed by `transfer`, making them unable to receive funds via
           * `transfer`. {sendValue} removes this limitation.
           *
           * https://diligence.consensys.net/posts/2019/09/stop-using-soliditys-transfer-now/[Learn more].
           *
           * IMPORTANT: because control is transferred to `recipient`, care must be
           * taken to not create reentrancy vulnerabilities. Consider using
           * {ReentrancyGuard} or the
           * https://solidity.readthedocs.io/en/v0.5.11/security-considerations.html#use-the-checks-effects-interactions-pattern[checks-effects-interactions pattern].
           */
          function sendValue(address payable recipient, uint256 amount) internal {
              require(address(this).balance >= amount, "Address: insufficient balance");
              (bool success, ) = recipient.call{value: amount}("");
              require(success, "Address: unable to send value, recipient may have reverted");
          }
          /**
           * @dev Performs a Solidity function call using a low level `call`. A
           * plain `call` is an unsafe replacement for a function call: use this
           * function instead.
           *
           * If `target` reverts with a revert reason, it is bubbled up by this
           * function (like regular Solidity function calls).
           *
           * Returns the raw returned data. To convert to the expected return value,
           * use https://solidity.readthedocs.io/en/latest/units-and-global-variables.html?highlight=abi.decode#abi-encoding-and-decoding-functions[`abi.decode`].
           *
           * Requirements:
           *
           * - `target` must be a contract.
           * - calling `target` with `data` must not revert.
           *
           * _Available since v3.1._
           */
          function functionCall(address target, bytes memory data) internal returns (bytes memory) {
              return functionCall(target, data, "Address: low-level call failed");
          }
          /**
           * @dev Same as {xref-Address-functionCall-address-bytes-}[`functionCall`], but with
           * `errorMessage` as a fallback revert reason when `target` reverts.
           *
           * _Available since v3.1._
           */
          function functionCall(
              address target,
              bytes memory data,
              string memory errorMessage
          ) internal returns (bytes memory) {
              return functionCallWithValue(target, data, 0, errorMessage);
          }
          /**
           * @dev Same as {xref-Address-functionCall-address-bytes-}[`functionCall`],
           * but also transferring `value` wei to `target`.
           *
           * Requirements:
           *
           * - the calling contract must have an ETH balance of at least `value`.
           * - the called Solidity function must be `payable`.
           *
           * _Available since v3.1._
           */
          function functionCallWithValue(
              address target,
              bytes memory data,
              uint256 value
          ) internal returns (bytes memory) {
              return functionCallWithValue(target, data, value, "Address: low-level call with value failed");
          }
          /**
           * @dev Same as {xref-Address-functionCallWithValue-address-bytes-uint256-}[`functionCallWithValue`], but
           * with `errorMessage` as a fallback revert reason when `target` reverts.
           *
           * _Available since v3.1._
           */
          function functionCallWithValue(
              address target,
              bytes memory data,
              uint256 value,
              string memory errorMessage
          ) internal returns (bytes memory) {
              require(address(this).balance >= value, "Address: insufficient balance for call");
              require(isContract(target), "Address: call to non-contract");
              (bool success, bytes memory returndata) = target.call{value: value}(data);
              return _verifyCallResult(success, returndata, errorMessage);
          }
          /**
           * @dev Same as {xref-Address-functionCall-address-bytes-}[`functionCall`],
           * but performing a static call.
           *
           * _Available since v3.3._
           */
          function functionStaticCall(address target, bytes memory data) internal view returns (bytes memory) {
              return functionStaticCall(target, data, "Address: low-level static call failed");
          }
          /**
           * @dev Same as {xref-Address-functionCall-address-bytes-string-}[`functionCall`],
           * but performing a static call.
           *
           * _Available since v3.3._
           */
          function functionStaticCall(
              address target,
              bytes memory data,
              string memory errorMessage
          ) internal view returns (bytes memory) {
              require(isContract(target), "Address: static call to non-contract");
              (bool success, bytes memory returndata) = target.staticcall(data);
              return _verifyCallResult(success, returndata, errorMessage);
          }
          /**
           * @dev Same as {xref-Address-functionCall-address-bytes-}[`functionCall`],
           * but performing a delegate call.
           *
           * _Available since v3.4._
           */
          function functionDelegateCall(address target, bytes memory data) internal returns (bytes memory) {
              return functionDelegateCall(target, data, "Address: low-level delegate call failed");
          }
          /**
           * @dev Same as {xref-Address-functionCall-address-bytes-string-}[`functionCall`],
           * but performing a delegate call.
           *
           * _Available since v3.4._
           */
          function functionDelegateCall(
              address target,
              bytes memory data,
              string memory errorMessage
          ) internal returns (bytes memory) {
              require(isContract(target), "Address: delegate call to non-contract");
              (bool success, bytes memory returndata) = target.delegatecall(data);
              return _verifyCallResult(success, returndata, errorMessage);
          }
          function _verifyCallResult(
              bool success,
              bytes memory returndata,
              string memory errorMessage
          ) private pure returns (bytes memory) {
              if (success) {
                  return returndata;
              } else {
                  // Look for revert reason and bubble it up if present
                  if (returndata.length > 0) {
                      // The easiest way to bubble the revert reason is using memory via assembly
                      assembly {
                          let returndata_size := mload(returndata)
                          revert(add(32, returndata), returndata_size)
                      }
                  } else {
                      revert(errorMessage);
                  }
              }
          }
      }
      // SPDX-License-Identifier: MIT
      pragma solidity ^0.8.0;
      /*
       * @dev Provides information about the current execution context, including the
       * sender of the transaction and its data. While these are generally available
       * via msg.sender and msg.data, they should not be accessed in such a direct
       * manner, since when dealing with meta-transactions the account sending and
       * paying for execution may not be the actual sender (as far as an application
       * is concerned).
       *
       * This contract is only required for intermediate, library-like contracts.
       */
      abstract contract Context {
          function _msgSender() internal view virtual returns (address) {
              return msg.sender;
          }
          function _msgData() internal view virtual returns (bytes calldata) {
              return msg.data;
          }
      }
      // SPDX-License-Identifier: MIT
      pragma solidity ^0.8.0;
      /**
       * @dev Elliptic Curve Digital Signature Algorithm (ECDSA) operations.
       *
       * These functions can be used to verify that a message was signed by the holder
       * of the private keys of a given address.
       */
      library ECDSA {
          /**
           * @dev Returns the address that signed a hashed message (`hash`) with
           * `signature`. This address can then be used for verification purposes.
           *
           * The `ecrecover` EVM opcode allows for malleable (non-unique) signatures:
           * this function rejects them by requiring the `s` value to be in the lower
           * half order, and the `v` value to be either 27 or 28.
           *
           * IMPORTANT: `hash` _must_ be the result of a hash operation for the
           * verification to be secure: it is possible to craft signatures that
           * recover to arbitrary addresses for non-hashed data. A safe way to ensure
           * this is by receiving a hash of the original message (which may otherwise
           * be too long), and then calling {toEthSignedMessageHash} on it.
           *
           * Documentation for signature generation:
           * - with https://web3js.readthedocs.io/en/v1.3.4/web3-eth-accounts.html#sign[Web3.js]
           * - with https://docs.ethers.io/v5/api/signer/#Signer-signMessage[ethers]
           */
          function recover(bytes32 hash, bytes memory signature) internal pure returns (address) {
              // Check the signature length
              // - case 65: r,s,v signature (standard)
              // - case 64: r,vs signature (cf https://eips.ethereum.org/EIPS/eip-2098) _Available since v4.1._
              if (signature.length == 65) {
                  bytes32 r;
                  bytes32 s;
                  uint8 v;
                  // ecrecover takes the signature parameters, and the only way to get them
                  // currently is to use assembly.
                  assembly {
                      r := mload(add(signature, 0x20))
                      s := mload(add(signature, 0x40))
                      v := byte(0, mload(add(signature, 0x60)))
                  }
                  return recover(hash, v, r, s);
              } else if (signature.length == 64) {
                  bytes32 r;
                  bytes32 vs;
                  // ecrecover takes the signature parameters, and the only way to get them
                  // currently is to use assembly.
                  assembly {
                      r := mload(add(signature, 0x20))
                      vs := mload(add(signature, 0x40))
                  }
                  return recover(hash, r, vs);
              } else {
                  revert("ECDSA: invalid signature length");
              }
          }
          /**
           * @dev Overload of {ECDSA-recover} that receives the `r` and `vs` short-signature fields separately.
           *
           * See https://eips.ethereum.org/EIPS/eip-2098[EIP-2098 short signatures]
           *
           * _Available since v4.2._
           */
          function recover(
              bytes32 hash,
              bytes32 r,
              bytes32 vs
          ) internal pure returns (address) {
              bytes32 s;
              uint8 v;
              assembly {
                  s := and(vs, 0x7fffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffff)
                  v := add(shr(255, vs), 27)
              }
              return recover(hash, v, r, s);
          }
          /**
           * @dev Overload of {ECDSA-recover} that receives the `v`, `r` and `s` signature fields separately.
           */
          function recover(
              bytes32 hash,
              uint8 v,
              bytes32 r,
              bytes32 s
          ) internal pure returns (address) {
              // EIP-2 still allows signature malleability for ecrecover(). Remove this possibility and make the signature
              // unique. Appendix F in the Ethereum Yellow paper (https://ethereum.github.io/yellowpaper/paper.pdf), defines
              // the valid range for s in (281): 0 < s < secp256k1n ÷ 2 + 1, and for v in (282): v ∈ {27, 28}. Most
              // signatures from current libraries generate a unique signature with an s-value in the lower half order.
              //
              // If your library generates malleable signatures, such as s-values in the upper range, calculate a new s-value
              // with 0xFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFEBAAEDCE6AF48A03BBFD25E8CD0364141 - s1 and flip v from 27 to 28 or
              // vice versa. If your library also generates signatures with 0/1 for v instead 27/28, add 27 to v to accept
              // these malleable signatures as well.
              require(
                  uint256(s) <= 0x7FFFFFFFFFFFFFFFFFFFFFFFFFFFFFFF5D576E7357A4501DDFE92F46681B20A0,
                  "ECDSA: invalid signature 's' value"
              );
              require(v == 27 || v == 28, "ECDSA: invalid signature 'v' value");
              // If the signature is valid (and not malleable), return the signer address
              address signer = ecrecover(hash, v, r, s);
              require(signer != address(0), "ECDSA: invalid signature");
              return signer;
          }
          /**
           * @dev Returns an Ethereum Signed Message, created from a `hash`. This
           * produces hash corresponding to the one signed with the
           * https://eth.wiki/json-rpc/API#eth_sign[`eth_sign`]
           * JSON-RPC method as part of EIP-191.
           *
           * See {recover}.
           */
          function toEthSignedMessageHash(bytes32 hash) internal pure returns (bytes32) {
              // 32 is the length in bytes of hash,
              // enforced by the type signature above
              return keccak256(abi.encodePacked("\\x19Ethereum Signed Message:\
      32", hash));
          }
          /**
           * @dev Returns an Ethereum Signed Typed Data, created from a
           * `domainSeparator` and a `structHash`. This produces hash corresponding
           * to the one signed with the
           * https://eips.ethereum.org/EIPS/eip-712[`eth_signTypedData`]
           * JSON-RPC method as part of EIP-712.
           *
           * See {recover}.
           */
          function toTypedDataHash(bytes32 domainSeparator, bytes32 structHash) internal pure returns (bytes32) {
              return keccak256(abi.encodePacked("\\x19\\x01", domainSeparator, structHash));
          }
      }
      // SPDX-License-Identifier: GPL-3.0-only
      pragma solidity 0.8.9;
      import "@openzeppelin/contracts/token/ERC20/IERC20.sol";
      import "@openzeppelin/contracts/token/ERC20/utils/SafeERC20.sol";
      import "./libraries/PbBridge.sol";
      import "./Pool.sol";
      contract Bridge is Pool {
          using SafeERC20 for IERC20;
          // liquidity events
          event Send(
              bytes32 transferId,
              address sender,
              address receiver,
              address token,
              uint256 amount,
              uint64 dstChainId,
              uint64 nonce,
              uint32 maxSlippage
          );
          event Relay(
              bytes32 transferId,
              address sender,
              address receiver,
              address token,
              uint256 amount,
              uint64 srcChainId,
              bytes32 srcTransferId
          );
          // gov events
          event MinSendUpdated(address token, uint256 amount);
          event MaxSendUpdated(address token, uint256 amount);
          mapping(bytes32 => bool) public transfers;
          mapping(address => uint256) public minSend; // send _amount must > minSend
          mapping(address => uint256) public maxSend;
          // min allowed max slippage uint32 value is slippage * 1M, eg. 0.5% -> 5000
          uint32 public minimalMaxSlippage;
          function send(
              address _receiver,
              address _token,
              uint256 _amount,
              uint64 _dstChainId,
              uint64 _nonce,
              uint32 _maxSlippage // slippage * 1M, eg. 0.5% -> 5000
          ) external nonReentrant whenNotPaused {
              bytes32 transferId = _send(_receiver, _token, _amount, _dstChainId, _nonce, _maxSlippage);
              IERC20(_token).safeTransferFrom(msg.sender, address(this), _amount);
              emit Send(transferId, msg.sender, _receiver, _token, _amount, _dstChainId, _nonce, _maxSlippage);
          }
          function sendNative(
              address _receiver,
              uint256 _amount,
              uint64 _dstChainId,
              uint64 _nonce,
              uint32 _maxSlippage
          ) external payable nonReentrant whenNotPaused {
              require(msg.value == _amount, "Amount mismatch");
              require(nativeWrap != address(0), "Native wrap not set");
              bytes32 transferId = _send(_receiver, nativeWrap, _amount, _dstChainId, _nonce, _maxSlippage);
              IWETH(nativeWrap).deposit{value: _amount}();
              emit Send(transferId, msg.sender, _receiver, nativeWrap, _amount, _dstChainId, _nonce, _maxSlippage);
          }
          function _send(
              address _receiver,
              address _token,
              uint256 _amount,
              uint64 _dstChainId,
              uint64 _nonce,
              uint32 _maxSlippage
          ) private returns (bytes32) {
              require(_amount > minSend[_token], "amount too small");
              require(maxSend[_token] == 0 || _amount <= maxSend[_token], "amount too large");
              require(_maxSlippage > minimalMaxSlippage, "max slippage too small");
              bytes32 transferId = keccak256(
                  // uint64(block.chainid) for consistency as entire system uses uint64 for chain id
                  abi.encodePacked(msg.sender, _receiver, _token, _amount, _dstChainId, _nonce, uint64(block.chainid))
              );
              require(transfers[transferId] == false, "transfer exists");
              transfers[transferId] = true;
              return transferId;
          }
          function relay(
              bytes calldata _relayRequest,
              bytes[] calldata _sigs,
              address[] calldata _signers,
              uint256[] calldata _powers
          ) external whenNotPaused {
              bytes32 domain = keccak256(abi.encodePacked(block.chainid, address(this), "Relay"));
              verifySigs(abi.encodePacked(domain, _relayRequest), _sigs, _signers, _powers);
              PbBridge.Relay memory request = PbBridge.decRelay(_relayRequest);
              bytes32 transferId = keccak256(
                  abi.encodePacked(
                      request.sender,
                      request.receiver,
                      request.token,
                      request.amount,
                      request.srcChainId,
                      request.dstChainId,
                      request.srcTransferId
                  )
              );
              require(transfers[transferId] == false, "transfer exists");
              transfers[transferId] = true;
              _updateVolume(request.token, request.amount);
              uint256 delayThreshold = delayThresholds[request.token];
              if (delayThreshold > 0 && request.amount > delayThreshold) {
                  _addDelayedTransfer(transferId, request.receiver, request.token, request.amount);
              } else {
                  _sendToken(request.receiver, request.token, request.amount);
              }
              emit Relay(
                  transferId,
                  request.sender,
                  request.receiver,
                  request.token,
                  request.amount,
                  request.srcChainId,
                  request.srcTransferId
              );
          }
          function setMinSend(address[] calldata _tokens, uint256[] calldata _amounts) external onlyGovernor {
              require(_tokens.length == _amounts.length, "length mismatch");
              for (uint256 i = 0; i < _tokens.length; i++) {
                  minSend[_tokens[i]] = _amounts[i];
                  emit MinSendUpdated(_tokens[i], _amounts[i]);
              }
          }
          function setMaxSend(address[] calldata _tokens, uint256[] calldata _amounts) external onlyGovernor {
              require(_tokens.length == _amounts.length, "length mismatch");
              for (uint256 i = 0; i < _tokens.length; i++) {
                  maxSend[_tokens[i]] = _amounts[i];
                  emit MaxSendUpdated(_tokens[i], _amounts[i]);
              }
          }
          function setMinimalMaxSlippage(uint32 _minimalMaxSlippage) external onlyGovernor {
              minimalMaxSlippage = _minimalMaxSlippage;
          }
          // This is needed to receive ETH when calling `IWETH.withdraw`
          receive() external payable {}
      }
      // SPDX-License-Identifier: GPL-3.0-only
      pragma solidity 0.8.9;
      import "@openzeppelin/contracts/token/ERC20/IERC20.sol";
      import "@openzeppelin/contracts/token/ERC20/utils/SafeERC20.sol";
      import "@openzeppelin/contracts/security/ReentrancyGuard.sol";
      import "./interfaces/IWETH.sol";
      import "./libraries/PbPool.sol";
      import "./safeguard/Pauser.sol";
      import "./safeguard/VolumeControl.sol";
      import "./safeguard/DelayedTransfer.sol";
      import "./Signers.sol";
      // add liquidity and withdraw
      // withdraw can be used by user or liquidity provider
      contract Pool is Signers, ReentrancyGuard, Pauser, VolumeControl, DelayedTransfer {
          using SafeERC20 for IERC20;
          uint64 public addseq; // ensure unique LiquidityAdded event, start from 1
          mapping(address => uint256) public minAdd; // add _amount must > minAdd
          // map of successful withdraws, if true means already withdrew money or added to delayedTransfers
          mapping(bytes32 => bool) public withdraws;
          // erc20 wrap of gas token of this chain, eg. WETH, when relay ie. pay out,
          // if request.token equals this, will withdraw and send native token to receiver
          // note we don't check whether it's zero address. when this isn't set, and request.token
          // is all 0 address, guarantee fail
          address public nativeWrap;
          // liquidity events
          event LiquidityAdded(
              uint64 seqnum,
              address provider,
              address token,
              uint256 amount // how many tokens were added
          );
          event WithdrawDone(
              bytes32 withdrawId,
              uint64 seqnum,
              address receiver,
              address token,
              uint256 amount,
              bytes32 refid
          );
          event MinAddUpdated(address token, uint256 amount);
          function addLiquidity(address _token, uint256 _amount) external nonReentrant whenNotPaused {
              require(_amount > minAdd[_token], "amount too small");
              addseq += 1;
              IERC20(_token).safeTransferFrom(msg.sender, address(this), _amount);
              emit LiquidityAdded(addseq, msg.sender, _token, _amount);
          }
          function addNativeLiquidity(uint256 _amount) external payable nonReentrant whenNotPaused {
              require(msg.value == _amount, "Amount mismatch");
              require(nativeWrap != address(0), "Native wrap not set");
              require(_amount > minAdd[nativeWrap], "amount too small");
              addseq += 1;
              IWETH(nativeWrap).deposit{value: _amount}();
              emit LiquidityAdded(addseq, msg.sender, nativeWrap, _amount);
          }
          function withdraw(
              bytes calldata _wdmsg,
              bytes[] calldata _sigs,
              address[] calldata _signers,
              uint256[] calldata _powers
          ) external whenNotPaused {
              bytes32 domain = keccak256(abi.encodePacked(block.chainid, address(this), "WithdrawMsg"));
              verifySigs(abi.encodePacked(domain, _wdmsg), _sigs, _signers, _powers);
              // decode and check wdmsg
              PbPool.WithdrawMsg memory wdmsg = PbPool.decWithdrawMsg(_wdmsg);
              bytes32 wdId = keccak256(
                  abi.encodePacked(wdmsg.chainid, wdmsg.seqnum, wdmsg.receiver, wdmsg.token, wdmsg.amount)
              );
              require(withdraws[wdId] == false, "withdraw already succeeded");
              withdraws[wdId] = true;
              _updateVolume(wdmsg.token, wdmsg.amount);
              uint256 delayThreshold = delayThresholds[wdmsg.token];
              if (delayThreshold > 0 && wdmsg.amount > delayThreshold) {
                  _addDelayedTransfer(wdId, wdmsg.receiver, wdmsg.token, wdmsg.amount);
              } else {
                  _sendToken(wdmsg.receiver, wdmsg.token, wdmsg.amount);
              }
              emit WithdrawDone(wdId, wdmsg.seqnum, wdmsg.receiver, wdmsg.token, wdmsg.amount, wdmsg.refid);
          }
          function executeDelayedTransfer(bytes32 id) external whenNotPaused {
              delayedTransfer memory transfer = _executeDelayedTransfer(id);
              _sendToken(transfer.receiver, transfer.token, transfer.amount);
          }
          function setMinAdd(address[] calldata _tokens, uint256[] calldata _amounts) external onlyGovernor {
              require(_tokens.length == _amounts.length, "length mismatch");
              for (uint256 i = 0; i < _tokens.length; i++) {
                  minAdd[_tokens[i]] = _amounts[i];
                  emit MinAddUpdated(_tokens[i], _amounts[i]);
              }
          }
          function _sendToken(
              address _receiver,
              address _token,
              uint256 _amount
          ) internal {
              if (_token == nativeWrap) {
                  // withdraw then transfer native to receiver
                  IWETH(nativeWrap).withdraw(_amount);
                  (bool sent, ) = _receiver.call{value: _amount, gas: 50000}("");
                  require(sent, "failed to send native token");
              } else {
                  IERC20(_token).safeTransfer(_receiver, _amount);
              }
          }
          // set nativeWrap, for relay requests, if token == nativeWrap, will withdraw first then transfer native to receiver
          function setWrap(address _weth) external onlyOwner {
              nativeWrap = _weth;
          }
      }
      // SPDX-License-Identifier: GPL-3.0-only
      pragma solidity 0.8.9;
      import "@openzeppelin/contracts/utils/cryptography/ECDSA.sol";
      import "@openzeppelin/contracts/access/Ownable.sol";
      import "./interfaces/ISigsVerifier.sol";
      contract Signers is Ownable, ISigsVerifier {
          using ECDSA for bytes32;
          bytes32 public ssHash;
          uint256 public triggerTime; // timestamp when last update was triggered
          // reset can be called by the owner address for emergency recovery
          uint256 public resetTime;
          uint256 public noticePeriod; // advance notice period as seconds for reset
          uint256 constant MAX_INT = 2**256 - 1;
          event SignersUpdated(address[] _signers, uint256[] _powers);
          event ResetNotification(uint256 resetTime);
          /**
           * @notice Verifies that a message is signed by a quorum among the signers
           * The sigs must be sorted by signer addresses in ascending order.
           * @param _msg signed message
           * @param _sigs list of signatures sorted by signer addresses
           * @param _signers sorted list of current signers
           * @param _powers powers of current signers
           */
          function verifySigs(
              bytes memory _msg,
              bytes[] calldata _sigs,
              address[] calldata _signers,
              uint256[] calldata _powers
          ) public view override {
              bytes32 h = keccak256(abi.encodePacked(_signers, _powers));
              require(ssHash == h, "Mismatch current signers");
              _verifySignedPowers(keccak256(_msg).toEthSignedMessageHash(), _sigs, _signers, _powers);
          }
          /**
           * @notice Update new signers.
           * @param _newSigners sorted list of new signers
           * @param _curPowers powers of new signers
           * @param _sigs list of signatures sorted by signer addresses
           * @param _curSigners sorted list of current signers
           * @param _curPowers powers of current signers
           */
          function updateSigners(
              uint256 _triggerTime,
              address[] calldata _newSigners,
              uint256[] calldata _newPowers,
              bytes[] calldata _sigs,
              address[] calldata _curSigners,
              uint256[] calldata _curPowers
          ) external {
              // use trigger time for nonce protection, must be ascending
              require(_triggerTime > triggerTime, "Trigger time is not increasing");
              // make sure triggerTime is not too large, as it cannot be decreased once set
              require(_triggerTime < block.timestamp + 3600, "Trigger time is too large");
              bytes32 domain = keccak256(abi.encodePacked(block.chainid, address(this), "UpdateSigners"));
              verifySigs(abi.encodePacked(domain, _triggerTime, _newSigners, _newPowers), _sigs, _curSigners, _curPowers);
              _updateSigners(_newSigners, _newPowers);
              triggerTime = _triggerTime;
          }
          /**
           * @notice reset signers, only used for init setup and emergency recovery
           */
          function resetSigners(address[] calldata _signers, uint256[] calldata _powers) external onlyOwner {
              require(block.timestamp > resetTime, "not reach reset time");
              resetTime = MAX_INT;
              _updateSigners(_signers, _powers);
          }
          function notifyResetSigners() external onlyOwner {
              resetTime = block.timestamp + noticePeriod;
              emit ResetNotification(resetTime);
          }
          function increaseNoticePeriod(uint256 period) external onlyOwner {
              require(period > noticePeriod, "notice period can only be increased");
              noticePeriod = period;
          }
          // separate from verifySigs func to avoid "stack too deep" issue
          function _verifySignedPowers(
              bytes32 _hash,
              bytes[] calldata _sigs,
              address[] calldata _signers,
              uint256[] calldata _powers
          ) private pure {
              require(_signers.length == _powers.length, "signers and powers length not match");
              uint256 totalPower; // sum of all signer.power
              for (uint256 i = 0; i < _signers.length; i++) {
                  totalPower += _powers[i];
              }
              uint256 quorum = (totalPower * 2) / 3 + 1;
              uint256 signedPower; // sum of signer powers who are in sigs
              address prev = address(0);
              uint256 index = 0;
              for (uint256 i = 0; i < _sigs.length; i++) {
                  address signer = _hash.recover(_sigs[i]);
                  require(signer > prev, "signers not in ascending order");
                  prev = signer;
                  // now find match signer add its power
                  while (signer > _signers[index]) {
                      index += 1;
                      require(index < _signers.length, "signer not found");
                  }
                  if (signer == _signers[index]) {
                      signedPower += _powers[index];
                  }
                  if (signedPower >= quorum) {
                      // return early to save gas
                      return;
                  }
              }
              revert("quorum not reached");
          }
          function _updateSigners(address[] calldata _signers, uint256[] calldata _powers) private {
              require(_signers.length == _powers.length, "signers and powers length not match");
              address prev = address(0);
              for (uint256 i = 0; i < _signers.length; i++) {
                  require(_signers[i] > prev, "New signers not in ascending order");
                  prev = _signers[i];
              }
              ssHash = keccak256(abi.encodePacked(_signers, _powers));
              emit SignersUpdated(_signers, _powers);
          }
      }
      // SPDX-License-Identifier: GPL-3.0-only
      pragma solidity 0.8.9;
      interface ISigsVerifier {
          /**
           * @notice Verifies that a message is signed by a quorum among the signers.
           * @param _msg signed message
           * @param _sigs list of signatures sorted by signer addresses
           * @param _signers sorted list of current signers
           * @param _powers powers of current signers
           */
          function verifySigs(
              bytes memory _msg,
              bytes[] calldata _sigs,
              address[] calldata _signers,
              uint256[] calldata _powers
          ) external view;
      }
      // SPDX-License-Identifier: GPL-3.0-only
      pragma solidity 0.8.9;
      interface IWETH {
          function deposit() external payable;
          function withdraw(uint256) external;
      }
      // SPDX-License-Identifier: GPL-3.0-only
      pragma solidity 0.8.9;
      // runtime proto sol library
      library Pb {
          enum WireType {
              Varint,
              Fixed64,
              LengthDelim,
              StartGroup,
              EndGroup,
              Fixed32
          }
          struct Buffer {
              uint256 idx; // the start index of next read. when idx=b.length, we're done
              bytes b; // hold serialized proto msg, readonly
          }
          // create a new in-memory Buffer object from raw msg bytes
          function fromBytes(bytes memory raw) internal pure returns (Buffer memory buf) {
              buf.b = raw;
              buf.idx = 0;
          }
          // whether there are unread bytes
          function hasMore(Buffer memory buf) internal pure returns (bool) {
              return buf.idx < buf.b.length;
          }
          // decode current field number and wiretype
          function decKey(Buffer memory buf) internal pure returns (uint256 tag, WireType wiretype) {
              uint256 v = decVarint(buf);
              tag = v / 8;
              wiretype = WireType(v & 7);
          }
          // count tag occurrences, return an array due to no memory map support
          // have to create array for (maxtag+1) size. cnts[tag] = occurrences
          // should keep buf.idx unchanged because this is only a count function
          function cntTags(Buffer memory buf, uint256 maxtag) internal pure returns (uint256[] memory cnts) {
              uint256 originalIdx = buf.idx;
              cnts = new uint256[](maxtag + 1); // protobuf's tags are from 1 rather than 0
              uint256 tag;
              WireType wire;
              while (hasMore(buf)) {
                  (tag, wire) = decKey(buf);
                  cnts[tag] += 1;
                  skipValue(buf, wire);
              }
              buf.idx = originalIdx;
          }
          // read varint from current buf idx, move buf.idx to next read, return the int value
          function decVarint(Buffer memory buf) internal pure returns (uint256 v) {
              bytes10 tmp; // proto int is at most 10 bytes (7 bits can be used per byte)
              bytes memory bb = buf.b; // get buf.b mem addr to use in assembly
              v = buf.idx; // use v to save one additional uint variable
              assembly {
                  tmp := mload(add(add(bb, 32), v)) // load 10 bytes from buf.b[buf.idx] to tmp
              }
              uint256 b; // store current byte content
              v = 0; // reset to 0 for return value
              for (uint256 i = 0; i < 10; i++) {
                  assembly {
                      b := byte(i, tmp) // don't use tmp[i] because it does bound check and costs extra
                  }
                  v |= (b & 0x7F) << (i * 7);
                  if (b & 0x80 == 0) {
                      buf.idx += i + 1;
                      return v;
                  }
              }
              revert(); // i=10, invalid varint stream
          }
          // read length delimited field and return bytes
          function decBytes(Buffer memory buf) internal pure returns (bytes memory b) {
              uint256 len = decVarint(buf);
              uint256 end = buf.idx + len;
              require(end <= buf.b.length); // avoid overflow
              b = new bytes(len);
              bytes memory bufB = buf.b; // get buf.b mem addr to use in assembly
              uint256 bStart;
              uint256 bufBStart = buf.idx;
              assembly {
                  bStart := add(b, 32)
                  bufBStart := add(add(bufB, 32), bufBStart)
              }
              for (uint256 i = 0; i < len; i += 32) {
                  assembly {
                      mstore(add(bStart, i), mload(add(bufBStart, i)))
                  }
              }
              buf.idx = end;
          }
          // return packed ints
          function decPacked(Buffer memory buf) internal pure returns (uint256[] memory t) {
              uint256 len = decVarint(buf);
              uint256 end = buf.idx + len;
              require(end <= buf.b.length); // avoid overflow
              // array in memory must be init w/ known length
              // so we have to create a tmp array w/ max possible len first
              uint256[] memory tmp = new uint256[](len);
              uint256 i = 0; // count how many ints are there
              while (buf.idx < end) {
                  tmp[i] = decVarint(buf);
                  i++;
              }
              t = new uint256[](i); // init t with correct length
              for (uint256 j = 0; j < i; j++) {
                  t[j] = tmp[j];
              }
              return t;
          }
          // move idx pass current value field, to beginning of next tag or msg end
          function skipValue(Buffer memory buf, WireType wire) internal pure {
              if (wire == WireType.Varint) {
                  decVarint(buf);
              } else if (wire == WireType.LengthDelim) {
                  uint256 len = decVarint(buf);
                  buf.idx += len; // skip len bytes value data
                  require(buf.idx <= buf.b.length); // avoid overflow
              } else {
                  revert();
              } // unsupported wiretype
          }
          // type conversion help utils
          function _bool(uint256 x) internal pure returns (bool v) {
              return x != 0;
          }
          function _uint256(bytes memory b) internal pure returns (uint256 v) {
              require(b.length <= 32); // b's length must be smaller than or equal to 32
              assembly {
                  v := mload(add(b, 32))
              } // load all 32bytes to v
              v = v >> (8 * (32 - b.length)); // only first b.length is valid
          }
          function _address(bytes memory b) internal pure returns (address v) {
              v = _addressPayable(b);
          }
          function _addressPayable(bytes memory b) internal pure returns (address payable v) {
              require(b.length == 20);
              //load 32bytes then shift right 12 bytes
              assembly {
                  v := div(mload(add(b, 32)), 0x1000000000000000000000000)
              }
          }
          function _bytes32(bytes memory b) internal pure returns (bytes32 v) {
              require(b.length == 32);
              assembly {
                  v := mload(add(b, 32))
              }
          }
          // uint[] to uint8[]
          function uint8s(uint256[] memory arr) internal pure returns (uint8[] memory t) {
              t = new uint8[](arr.length);
              for (uint256 i = 0; i < t.length; i++) {
                  t[i] = uint8(arr[i]);
              }
          }
          function uint32s(uint256[] memory arr) internal pure returns (uint32[] memory t) {
              t = new uint32[](arr.length);
              for (uint256 i = 0; i < t.length; i++) {
                  t[i] = uint32(arr[i]);
              }
          }
          function uint64s(uint256[] memory arr) internal pure returns (uint64[] memory t) {
              t = new uint64[](arr.length);
              for (uint256 i = 0; i < t.length; i++) {
                  t[i] = uint64(arr[i]);
              }
          }
          function bools(uint256[] memory arr) internal pure returns (bool[] memory t) {
              t = new bool[](arr.length);
              for (uint256 i = 0; i < t.length; i++) {
                  t[i] = arr[i] != 0;
              }
          }
      }
      // SPDX-License-Identifier: GPL-3.0-only
      // Code generated by protoc-gen-sol. DO NOT EDIT.
      // source: bridge.proto
      pragma solidity 0.8.9;
      import "./Pb.sol";
      library PbBridge {
          using Pb for Pb.Buffer; // so we can call Pb funcs on Buffer obj
          struct Relay {
              address sender; // tag: 1
              address receiver; // tag: 2
              address token; // tag: 3
              uint256 amount; // tag: 4
              uint64 srcChainId; // tag: 5
              uint64 dstChainId; // tag: 6
              bytes32 srcTransferId; // tag: 7
          } // end struct Relay
          function decRelay(bytes memory raw) internal pure returns (Relay memory m) {
              Pb.Buffer memory buf = Pb.fromBytes(raw);
              uint256 tag;
              Pb.WireType wire;
              while (buf.hasMore()) {
                  (tag, wire) = buf.decKey();
                  if (false) {}
                  // solidity has no switch/case
                  else if (tag == 1) {
                      m.sender = Pb._address(buf.decBytes());
                  } else if (tag == 2) {
                      m.receiver = Pb._address(buf.decBytes());
                  } else if (tag == 3) {
                      m.token = Pb._address(buf.decBytes());
                  } else if (tag == 4) {
                      m.amount = Pb._uint256(buf.decBytes());
                  } else if (tag == 5) {
                      m.srcChainId = uint64(buf.decVarint());
                  } else if (tag == 6) {
                      m.dstChainId = uint64(buf.decVarint());
                  } else if (tag == 7) {
                      m.srcTransferId = Pb._bytes32(buf.decBytes());
                  } else {
                      buf.skipValue(wire);
                  } // skip value of unknown tag
              }
          } // end decoder Relay
      }
      // SPDX-License-Identifier: GPL-3.0-only
      // Code generated by protoc-gen-sol. DO NOT EDIT.
      // source: contracts/libraries/proto/pool.proto
      pragma solidity 0.8.9;
      import "./Pb.sol";
      library PbPool {
          using Pb for Pb.Buffer; // so we can call Pb funcs on Buffer obj
          struct WithdrawMsg {
              uint64 chainid; // tag: 1
              uint64 seqnum; // tag: 2
              address receiver; // tag: 3
              address token; // tag: 4
              uint256 amount; // tag: 5
              bytes32 refid; // tag: 6
          } // end struct WithdrawMsg
          function decWithdrawMsg(bytes memory raw) internal pure returns (WithdrawMsg memory m) {
              Pb.Buffer memory buf = Pb.fromBytes(raw);
              uint256 tag;
              Pb.WireType wire;
              while (buf.hasMore()) {
                  (tag, wire) = buf.decKey();
                  if (false) {}
                  // solidity has no switch/case
                  else if (tag == 1) {
                      m.chainid = uint64(buf.decVarint());
                  } else if (tag == 2) {
                      m.seqnum = uint64(buf.decVarint());
                  } else if (tag == 3) {
                      m.receiver = Pb._address(buf.decBytes());
                  } else if (tag == 4) {
                      m.token = Pb._address(buf.decBytes());
                  } else if (tag == 5) {
                      m.amount = Pb._uint256(buf.decBytes());
                  } else if (tag == 6) {
                      m.refid = Pb._bytes32(buf.decBytes());
                  } else {
                      buf.skipValue(wire);
                  } // skip value of unknown tag
              }
          } // end decoder WithdrawMsg
      }
      // SPDX-License-Identifier: GPL-3.0-only
      pragma solidity 0.8.9;
      import "./Governor.sol";
      abstract contract DelayedTransfer is Governor {
          struct delayedTransfer {
              address receiver;
              address token;
              uint256 amount;
              uint256 timestamp;
          }
          mapping(bytes32 => delayedTransfer) public delayedTransfers;
          mapping(address => uint256) public delayThresholds;
          uint256 public delayPeriod; // in seconds
          event DelayedTransferAdded(bytes32 id);
          event DelayedTransferExecuted(bytes32 id, address receiver, address token, uint256 amount);
          event DelayPeriodUpdated(uint256 period);
          event DelayThresholdUpdated(address token, uint256 threshold);
          function setDelayThresholds(address[] calldata _tokens, uint256[] calldata _thresholds) external onlyGovernor {
              require(_tokens.length == _thresholds.length, "length mismatch");
              for (uint256 i = 0; i < _tokens.length; i++) {
                  delayThresholds[_tokens[i]] = _thresholds[i];
                  emit DelayThresholdUpdated(_tokens[i], _thresholds[i]);
              }
          }
          function setDelayPeriod(uint256 _period) external onlyGovernor {
              delayPeriod = _period;
              emit DelayPeriodUpdated(_period);
          }
          function _addDelayedTransfer(
              bytes32 id,
              address receiver,
              address token,
              uint256 amount
          ) internal {
              require(delayedTransfers[id].timestamp == 0, "delayed transfer already exists");
              delayedTransfers[id] = delayedTransfer({
                  receiver: receiver,
                  token: token,
                  amount: amount,
                  timestamp: block.timestamp
              });
              emit DelayedTransferAdded(id);
          }
          // caller needs to do the actual token transfer
          function _executeDelayedTransfer(bytes32 id) internal returns (delayedTransfer memory) {
              delayedTransfer memory transfer = delayedTransfers[id];
              require(transfer.timestamp > 0, "delayed transfer not exist");
              require(block.timestamp > transfer.timestamp + delayPeriod, "delayed transfer still locked");
              delete delayedTransfers[id];
              emit DelayedTransferExecuted(id, transfer.receiver, transfer.token, transfer.amount);
              return transfer;
          }
      }
      // SPDX-License-Identifier: GPL-3.0-only
      pragma solidity 0.8.9;
      import "@openzeppelin/contracts/access/Ownable.sol";
      abstract contract Governor is Ownable {
          mapping(address => bool) public governors;
          event GovernorAdded(address account);
          event GovernorRemoved(address account);
          modifier onlyGovernor() {
              require(isGovernor(msg.sender), "Caller is not governor");
              _;
          }
          constructor() {
              _addGovernor(msg.sender);
          }
          function isGovernor(address _account) public view returns (bool) {
              return governors[_account];
          }
          function addGovernor(address _account) public onlyOwner {
              _addGovernor(_account);
          }
          function removeGovernor(address _account) public onlyOwner {
              _removeGovernor(_account);
          }
          function renounceGovernor() public {
              _removeGovernor(msg.sender);
          }
          function _addGovernor(address _account) private {
              require(!isGovernor(_account), "Account is already governor");
              governors[_account] = true;
              emit GovernorAdded(_account);
          }
          function _removeGovernor(address _account) private {
              require(isGovernor(_account), "Account is not governor");
              governors[_account] = false;
              emit GovernorRemoved(_account);
          }
      }
      // SPDX-License-Identifier: GPL-3.0-only
      pragma solidity 0.8.9;
      import "@openzeppelin/contracts/access/Ownable.sol";
      import "@openzeppelin/contracts/security/Pausable.sol";
      abstract contract Pauser is Ownable, Pausable {
          mapping(address => bool) public pausers;
          event PauserAdded(address account);
          event PauserRemoved(address account);
          constructor() {
              _addPauser(msg.sender);
          }
          modifier onlyPauser() {
              require(isPauser(msg.sender), "Caller is not pauser");
              _;
          }
          function pause() public onlyPauser {
              _pause();
          }
          function unpause() public onlyPauser {
              _unpause();
          }
          function isPauser(address account) public view returns (bool) {
              return pausers[account];
          }
          function addPauser(address account) public onlyOwner {
              _addPauser(account);
          }
          function removePauser(address account) public onlyOwner {
              _removePauser(account);
          }
          function renouncePauser() public {
              _removePauser(msg.sender);
          }
          function _addPauser(address account) private {
              require(!isPauser(account), "Account is already pauser");
              pausers[account] = true;
              emit PauserAdded(account);
          }
          function _removePauser(address account) private {
              require(isPauser(account), "Account is not pauser");
              pausers[account] = false;
              emit PauserRemoved(account);
          }
      }
      // SPDX-License-Identifier: GPL-3.0-only
      pragma solidity 0.8.9;
      import "./Governor.sol";
      abstract contract VolumeControl is Governor {
          uint256 public epochLength; // seconds
          mapping(address => uint256) public epochVolumes; // key is token
          mapping(address => uint256) public epochVolumeCaps; // key is token
          mapping(address => uint256) public lastOpTimestamps; // key is token
          event EpochLengthUpdated(uint256 length);
          event EpochVolumeUpdated(address token, uint256 cap);
          function setEpochLength(uint256 _length) external onlyGovernor {
              epochLength = _length;
              emit EpochLengthUpdated(_length);
          }
          function setEpochVolumeCaps(address[] calldata _tokens, uint256[] calldata _caps) external onlyGovernor {
              require(_tokens.length == _caps.length, "length mismatch");
              for (uint256 i = 0; i < _tokens.length; i++) {
                  epochVolumeCaps[_tokens[i]] = _caps[i];
                  emit EpochVolumeUpdated(_tokens[i], _caps[i]);
              }
          }
          function _updateVolume(address _token, uint256 _amount) internal {
              if (epochLength == 0) {
                  return;
              }
              uint256 cap = epochVolumeCaps[_token];
              if (cap == 0) {
                  return;
              }
              uint256 volume = epochVolumes[_token];
              uint256 timestamp = block.timestamp;
              uint256 epochStartTime = (timestamp / epochLength) * epochLength;
              if (lastOpTimestamps[_token] < epochStartTime) {
                  volume = _amount;
              } else {
                  volume += _amount;
              }
              require(volume <= cap, "volume exceeds cap");
              epochVolumes[_token] = volume;
              lastOpTimestamps[_token] = timestamp;
          }
      }