// Dependency file: contracts/token/IERC20.sol
// pragma solidity ^0.5.0;
/**
* @dev Interface of the ERC20 standard as defined in the EIP. Does not include
* the optional functions; to access them see {ERC20Detailed}.
*/
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
);
}
// Dependency file: contracts/IToken.sol
// pragma solidity ^0.5.0;
interface IToken {
function mint(address to, uint256 amount) external;
function updateAdmin(address newAdmin) external;
}
// Dependency file: contracts/GSN/Context.sol
// pragma solidity ^0.5.0;
/*
* @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 GSN 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.
*/
contract Context {
// Empty internal constructor, to prevent people from mistakenly deploying
// an instance of this contract, which should be used via inheritance.
constructor() internal {}
// solhint-disable-previous-line no-empty-blocks
function _msgSender() internal view returns (address payable) {
return msg.sender;
}
function _msgData() internal view returns (bytes memory) {
this; // silence state mutability warning without generating bytecode - see https://github.com/ethereum/solidity/issues/2691
return msg.data;
}
}
// Dependency file: contracts/BridgeBase.sol
// pragma solidity ^0.5.0;
// import 'contracts/token/IERC20.sol';
// import 'contracts/IToken.sol';
// import 'contracts/GSN/Context.sol';
contract BridgeBase is Context {
address public admin;
IToken public token;
mapping(uint256 => bool) public processedNonces;
enum Step {Burn, Mint}
event CrossTransfer(
address from,
address to,
uint256 amount,
uint256 date,
uint256 nonce,
Step indexed step
);
constructor(address _token) public {
admin = _msgSender();
token = IToken(_token);
}
modifier onlyAdmin() {
require(
_msgSender() == admin,
'Only admin is allowed to execute this operation.'
);
_;
}
function updateAdmin(address newAdmin) external onlyAdmin {
admin = newAdmin;
}
function updateTokenAdmin(address newAdmin) external onlyAdmin {
token.updateAdmin(newAdmin);
}
function isProcessed(uint256 _nonce) external view returns (bool) {
return processedNonces[_nonce];
}
function mint(
address to,
uint256 amount,
uint256 otherChainNonce
) external onlyAdmin {
require(
processedNonces[otherChainNonce] == false,
'transfer already processed'
);
processedNonces[otherChainNonce] = true;
token.mint(to, amount);
emit CrossTransfer(
_msgSender(),
to,
amount,
block.timestamp,
otherChainNonce,
Step.Mint
);
}
}
// Root file: contracts/BridgeEth.sol
pragma solidity ^0.5.0;
// import "contracts/BridgeBase.sol";
contract BridgeEth is BridgeBase {
constructor(address token) public BridgeBase(token) {}
}
{
"compilationTarget": {
"BridgeEth.sol": "BridgeEth"
},
"evmVersion": "byzantium",
"libraries": {},
"optimizer": {
"enabled": false,
"runs": 200
},
"remappings": []
}
[{"constant":false,"inputs":[{"name":"to","type":"address"},{"name":"amount","type":"uint256"},{"name":"otherChainNonce","type":"uint256"}],"name":"mint","outputs":[],"payable":false,"stateMutability":"nonpayable","type":"function"},{"constant":true,"inputs":[{"name":"","type":"uint256"}],"name":"processedNonces","outputs":[{"name":"","type":"bool"}],"payable":false,"stateMutability":"view","type":"function"},{"constant":true,"inputs":[{"name":"_nonce","type":"uint256"}],"name":"isProcessed","outputs":[{"name":"","type":"bool"}],"payable":false,"stateMutability":"view","type":"function"},{"constant":false,"inputs":[{"name":"newAdmin","type":"address"}],"name":"updateTokenAdmin","outputs":[],"payable":false,"stateMutability":"nonpayable","type":"function"},{"constant":false,"inputs":[{"name":"newAdmin","type":"address"}],"name":"updateAdmin","outputs":[],"payable":false,"stateMutability":"nonpayable","type":"function"},{"constant":true,"inputs":[],"name":"admin","outputs":[{"name":"","type":"address"}],"payable":false,"stateMutability":"view","type":"function"},{"constant":true,"inputs":[],"name":"token","outputs":[{"name":"","type":"address"}],"payable":false,"stateMutability":"view","type":"function"},{"inputs":[{"name":"token","type":"address"}],"payable":false,"stateMutability":"nonpayable","type":"constructor"},{"anonymous":false,"inputs":[{"indexed":false,"name":"from","type":"address"},{"indexed":false,"name":"to","type":"address"},{"indexed":false,"name":"amount","type":"uint256"},{"indexed":false,"name":"date","type":"uint256"},{"indexed":false,"name":"nonce","type":"uint256"},{"indexed":true,"name":"step","type":"uint8"}],"name":"CrossTransfer","type":"event"}]