// File: @openzeppelin/contracts/token/ERC20/IERC20.sol
// OpenZeppelin Contracts (last updated v5.0.0) (token/ERC20/IERC20.sol)
pragma solidity ^0.8.20;
/**
* @dev Interface of the ERC20 standard as defined in the EIP.
*/
interface IERC20 {
/**
* @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);
/**
* @dev Returns the value of tokens in existence.
*/
function totalSupply() external view returns (uint256);
/**
* @dev Returns the value of tokens owned by `account`.
*/
function balanceOf(address account) external view returns (uint256);
/**
* @dev Moves a `value` amount of 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 value) 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 a `value` amount of tokens 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 value) external returns (bool);
/**
* @dev Moves a `value` amount of tokens from `from` to `to` using the
* allowance mechanism. `value` 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 value) external returns (bool);
}
// File: @openzeppelin/contracts/security/ReentrancyGuard.sol
// OpenZeppelin Contracts (last updated v4.9.0) (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() {
_nonReentrantBefore();
_;
_nonReentrantAfter();
}
function _nonReentrantBefore() private {
// On the first call to nonReentrant, _status will be _NOT_ENTERED
require(_status != _ENTERED, "ReentrancyGuard: reentrant call");
// Any calls to nonReentrant after this point will fail
_status = _ENTERED;
}
function _nonReentrantAfter() private {
// By storing the original value once again, a refund is triggered (see
// https://eips.ethereum.org/EIPS/eip-2200)
_status = _NOT_ENTERED;
}
/**
* @dev Returns true if the reentrancy guard is currently set to "entered", which indicates there is a
* `nonReentrant` function in the call stack.
*/
function _reentrancyGuardEntered() internal view returns (bool) {
return _status == _ENTERED;
}
}
// File: bridge2.sol
pragma solidity ^0.8.0;
// Import the ERC20 interface
// Import ReentrancyGuard from OpenZeppelin
contract Bridge is ReentrancyGuard {
address public owner = msg.sender;
address public constant basedmc = 0x96A07274aBf958Aa04a05b87434DF4cd1BC77e06;
IERC20 public ourToken;
event Bridged(address indexed user, uint256 amount);
event Withdraw(address indexed user, uint256 amount, uint256 gasSent);
constructor() {
ourToken = IERC20(basedmc);
}
function bridge(uint256 _amount) public nonReentrant {
require(ourToken.allowance(msg.sender, address(this)) >= _amount, "Not approved for transfer");
require(ourToken.balanceOf(msg.sender) >= _amount, "Not enough tokens for bridge");
ourToken.transferFrom(msg.sender, owner, _amount);
emit Bridged(msg.sender, _amount);
}
function withdraw(uint256 _amount) public payable nonReentrant {
payable(owner).transfer(msg.value); // user sent gas for the server to use
emit Withdraw(msg.sender, _amount, msg.value); // this event confirms to the server that gas was sent
}
function rescueETH() public nonReentrant {
require(msg.sender == owner, "Transaction sender is not creator");
require(address(this).balance > 0, "Insufficient funds in the contract");
payable(owner).transfer(address(this).balance);
}
function rescueToken(uint256 _amount) public nonReentrant {
require(msg.sender == owner, "Transaction sender is not creator");
require(ourToken.balanceOf(address(this)) >= _amount, "Insufficient balance");
ourToken.transfer(msg.sender, _amount);
}
}
{
"compilationTarget": {
"Bridge.sol": "Bridge"
},
"evmVersion": "cancun",
"libraries": {},
"metadata": {
"bytecodeHash": "ipfs"
},
"optimizer": {
"enabled": false,
"runs": 200
},
"remappings": []
}
[{"inputs":[],"stateMutability":"nonpayable","type":"constructor"},{"anonymous":false,"inputs":[{"indexed":true,"internalType":"address","name":"user","type":"address"},{"indexed":false,"internalType":"uint256","name":"amount","type":"uint256"}],"name":"Bridged","type":"event"},{"anonymous":false,"inputs":[{"indexed":true,"internalType":"address","name":"user","type":"address"},{"indexed":false,"internalType":"uint256","name":"amount","type":"uint256"},{"indexed":false,"internalType":"uint256","name":"gasSent","type":"uint256"}],"name":"Withdraw","type":"event"},{"inputs":[],"name":"basedmc","outputs":[{"internalType":"address","name":"","type":"address"}],"stateMutability":"view","type":"function"},{"inputs":[{"internalType":"uint256","name":"_amount","type":"uint256"}],"name":"bridge","outputs":[],"stateMutability":"nonpayable","type":"function"},{"inputs":[],"name":"ourToken","outputs":[{"internalType":"contract IERC20","name":"","type":"address"}],"stateMutability":"view","type":"function"},{"inputs":[],"name":"owner","outputs":[{"internalType":"address","name":"","type":"address"}],"stateMutability":"view","type":"function"},{"inputs":[],"name":"rescueETH","outputs":[],"stateMutability":"nonpayable","type":"function"},{"inputs":[{"internalType":"uint256","name":"_amount","type":"uint256"}],"name":"rescueToken","outputs":[],"stateMutability":"nonpayable","type":"function"},{"inputs":[{"internalType":"uint256","name":"_amount","type":"uint256"}],"name":"withdraw","outputs":[],"stateMutability":"payable","type":"function"}]