Solidity
Uniswap addLiquidity 功能交易還原
我嘗試了 addLiquidity 函式，但結果是事務恢復。我設置了最後期限 = block.timestamp 並使用了混音。為什麼交易被還原？我找到了問題行並在程式碼中指定了它。我認為
pair = address(uint(keccak256(abi.encodePacked( hex'ff', factory, keccak256(abi.encodePacked(token0, token1)), hex'96e8ac4277198ff8b6f785478aa9a39f403cb768dd02cbee326c3e7da348845f' // init code hash ))));我認為這段程式碼的第四個參數是錯誤的。什麼是初始化程式碼雜湊？以及如何找到並驗證初始化程式碼雜湊
謝謝
Txn 雜湊 https://kovan.etherscan.io/tx/0xe2bcef8c4d4fc1732b4604a73caf6213d6e3f5e1a33151392458eccff384ddca
pragma solidity >=0.5.0; import './IUniswapV2Pair.sol'; import "./SafeMath.sol"; library UniswapV2Library { using SafeMath for uint; // returns sorted token addresses, used to handle return values from pairs sorted in this order function sortTokens(address tokenA, address tokenB) internal pure returns (address token0, address token1) { require(tokenA != tokenB, 'UniswapV2Library: IDENTICAL_ADDRESSES'); (token0, token1) = tokenA < tokenB ? (tokenA, tokenB) : (tokenB, tokenA); require(token0 != address(0), 'UniswapV2Library: ZERO_ADDRESS'); } // calculates the CREATE2 address for a pair without making any external calls function pairFor(address factory, address tokenA, address tokenB) internal pure returns (address pair) { (address token0, address token1) = sortTokens(tokenA, tokenB); pair = address(uint(keccak256(abi.encodePacked( hex'ff', factory, keccak256(abi.encodePacked(token0, token1)), hex'96e8ac4277198ff8b6f785478aa9a39f403cb768dd02cbee326c3e7da348845f' // init code hash )))); } // fetches and sorts the reserves for a pair function getReserves(address factory, address tokenA, address tokenB) internal view returns (uint reserveA, uint reserveB) { (address token0,) = sortTokens(tokenA, tokenB); (uint reserve0, uint reserve1,) = IUniswapV2Pair(pairFor(factory, tokenA, tokenB)).getReserves(); (reserveA, reserveB) = tokenA == token0 ? (reserve0, reserve1) : (reserve1, reserve0); } // given some amount of an asset and pair reserves, returns an equivalent amount of the other asset function quote(uint amountA, uint reserveA, uint reserveB) internal pure returns (uint amountB) { require(amountA > 0, 'UniswapV2Library: INSUFFICIENT_AMOUNT'); require(reserveA > 0 && reserveB > 0, 'UniswapV2Library: INSUFFICIENT_LIQUIDITY'); amountB = amountA.mul(reserveB) / reserveA; } // given an input amount of an asset and pair reserves, returns the maximum output amount of the other asset function getAmountOut(uint amountIn, uint reserveIn, uint reserveOut) internal pure returns (uint amountOut) { require(amountIn > 0, 'UniswapV2Library: INSUFFICIENT_INPUT_AMOUNT'); require(reserveIn > 0 && reserveOut > 0, 'UniswapV2Library: INSUFFICIENT_LIQUIDITY'); uint amountInWithFee = amountIn.mul(997); uint numerator = amountInWithFee.mul(reserveOut); uint denominator = reserveIn.mul(1000).add(amountInWithFee); amountOut = numerator / denominator; } // given an output amount of an asset and pair reserves, returns a required input amount of the other asset function getAmountIn(uint amountOut, uint reserveIn, uint reserveOut) internal pure returns (uint amountIn) { require(amountOut > 0, 'UniswapV2Library: INSUFFICIENT_OUTPUT_AMOUNT'); require(reserveIn > 0 && reserveOut > 0, 'UniswapV2Library: INSUFFICIENT_LIQUIDITY'); uint numerator = reserveIn.mul(amountOut).mul(1000); uint denominator = reserveOut.sub(amountOut).mul(997); amountIn = (numerator / denominator).add(1); } // performs chained getAmountOut calculations on any number of pairs function getAmountsOut(address factory, uint amountIn, address[] memory path) internal view returns (uint[] memory amounts) { require(path.length >= 2, 'UniswapV2Library: INVALID_PATH'); amounts = new uint[](path.length); amounts[0] = amountIn; for (uint i; i < path.length - 1; i++) { (uint reserveIn, uint reserveOut) = getReserves(factory, path[i], path[i + 1]); amounts[i + 1] = getAmountOut(amounts[i], reserveIn, reserveOut); } } // performs chained getAmountIn calculations on any number of pairs function getAmountsIn(address factory, uint amountOut, address[] memory path) internal view returns (uint[] memory amounts) { require(path.length >= 2, 'UniswapV2Library: INVALID_PATH'); amounts = new uint[](path.length); amounts[amounts.length - 1] = amountOut; for (uint i = path.length - 1; i > 0; i--) { (uint reserveIn, uint reserveOut) = getReserves(factory, path[i - 1], path[i]); amounts[i - 1] = getAmountIn(amounts[i], reserveIn, reserveOut); } } }這是路由器契約
pragma solidity =0.6.6; import './IUniswapV2Factory.sol'; import './TransferHelper.sol'; import './IUniswapV2Pair.sol'; import './IUniswapV2Router02.sol'; import './UniswapV2Library.sol'; import './SafeMath.sol'; import './IERC20.sol'; import './IWETH.sol'; contract UniswapV2Router02 is IUniswapV2Router02 { using SafeMath for uint; address public immutable override factory; address public immutable override WETH; modifier ensure(uint deadline) { deadline = block.timestamp; require(deadline >= block.timestamp, 'UniswapV2Router: EXPIRED'); _; } constructor(address _factory, address _WETH) public { factory = _factory; WETH = _WETH; } receive() external payable { assert(msg.sender == WETH); // only accept ETH via fallback from the WETH contract } // **** ADD LIQUIDITY **** function _addLiquidity( address tokenA, address tokenB, uint amountADesired, uint amountBDesired, uint amountAMin, uint amountBMin ) internal virtual returns (uint amountA, uint amountB) { // create the pair if it doesn't exist yet if (IUniswapV2Factory(factory).getPair(tokenA, tokenB) == address(0)) { IUniswapV2Factory(factory).createPair(tokenA, tokenB); } (uint reserveA, uint reserveB) = UniswapV2Library.getReserves(factory, tokenA, tokenB); if (reserveA == 0 && reserveB == 0) { (amountA, amountB) = (amountADesired, amountBDesired); } else { uint amountBOptimal = UniswapV2Library.quote(amountADesired, reserveA, reserveB); if (amountBOptimal <= amountBDesired) { require(amountBOptimal >= amountBMin, 'UniswapV2Router: INSUFFICIENT_B_AMOUNT'); (amountA, amountB) = (amountADesired, amountBOptimal); } else { uint amountAOptimal = UniswapV2Library.quote(amountBDesired, reserveB, reserveA); assert(amountAOptimal <= amountADesired); require(amountAOptimal >= amountAMin, 'UniswapV2Router: INSUFFICIENT_A_AMOUNT'); (amountA, amountB) = (amountAOptimal, amountBDesired); } } } function addLiquidity( address tokenA, address tokenB, uint amountADesired, uint amountBDesired, uint amountAMin, uint amountBMin, address to, uint deadline ) external virtual override ensure(deadline) returns (uint amountA, uint amountB, uint liquidity) { deadline = block.timestamp; (amountA, amountB) = _addLiquidity(tokenA, tokenB, amountADesired, amountBDesired, amountAMin, amountBMin); //---------------------PROBLEM İS HERE--------------------------------/ address pair = UniswapV2Library.pairFor(factory, tokenA, tokenB); //---------------------PROBLEM İS HERE--------------------------------/ TransferHelper.safeTransferFrom(tokenA, msg.sender, pair, amountA); TransferHelper.safeTransferFrom(tokenB, msg.sender, pair, amountB); liquidity = IUniswapV2Pair(pair).mint(to); } function addLiquidityETH( address token, uint amountTokenDesired, uint amountTokenMin, uint amountETHMin, address to, uint deadline ) external virtual override payable ensure(deadline) returns (uint amountToken, uint amountETH, uint liquidity) { deadline = block.timestamp; (amountToken, amountETH) = _addLiquidity( token, WETH, amountTokenDesired, msg.value, amountTokenMin, amountETHMin ); address pair = UniswapV2Library.pairFor(factory, token, WETH); TransferHelper.safeTransferFrom(token, msg.sender, pair, amountToken); IWETH(WETH).deposit{value: amountETH}(); assert(IWETH(WETH).transfer(pair, amountETH)); liquidity = IUniswapV2Pair(pair).mint(to); // refund dust eth, if any if (msg.value > amountETH) TransferHelper.safeTransferETH(msg.sender, msg.value - amountETH); } // **** REMOVE LIQUIDITY **** function removeLiquidity( address tokenA, address tokenB, uint liquidity, uint amountAMin, uint amountBMin, address to, uint deadline ) public virtual override ensure(deadline) returns (uint amountA, uint amountB) { address pair = UniswapV2Library.pairFor(factory, tokenA, tokenB); IUniswapV2Pair(pair).transferFrom(msg.sender, pair, liquidity); // send liquidity to pair (uint amount0, uint amount1) = IUniswapV2Pair(pair).burn(to); (address token0,) = UniswapV2Library.sortTokens(tokenA, tokenB); (amountA, amountB) = tokenA == token0 ? (amount0, amount1) : (amount1, amount0); require(amountA >= amountAMin, 'UniswapV2Router: INSUFFICIENT_A_AMOUNT'); require(amountB >= amountBMin, 'UniswapV2Router: INSUFFICIENT_B_AMOUNT'); } function removeLiquidityETH( address token, uint liquidity, uint amountTokenMin, uint amountETHMin, address to, uint deadline ) public virtual override ensure(deadline) returns (uint amountToken, uint amountETH) { (amountToken, amountETH) = removeLiquidity( token, WETH, liquidity, amountTokenMin, amountETHMin, address(this), deadline ); TransferHelper.safeTransfer(token, to, amountToken); IWETH(WETH).withdraw(amountETH); TransferHelper.safeTransferETH(to, amountETH); } function removeLiquidityWithPermit( address tokenA, address tokenB, uint liquidity, uint amountAMin, uint amountBMin, address to, uint deadline, bool approveMax, uint8 v, bytes32 r, bytes32 s ) external virtual override returns (uint amountA, uint amountB) { address pair = UniswapV2Library.pairFor(factory, tokenA, tokenB); uint value = approveMax ? uint(-1) : liquidity; IUniswapV2Pair(pair).permit(msg.sender, address(this), value, deadline, v, r, s); (amountA, amountB) = removeLiquidity(tokenA, tokenB, liquidity, amountAMin, amountBMin, to, deadline); } function removeLiquidityETHWithPermit( address token, uint liquidity, uint amountTokenMin, uint amountETHMin, address to, uint deadline, bool approveMax, uint8 v, bytes32 r, bytes32 s ) external virtual override returns (uint amountToken, uint amountETH) { address pair = UniswapV2Library.pairFor(factory, token, WETH); uint value = approveMax ? uint(-1) : liquidity; IUniswapV2Pair(pair).permit(msg.sender, address(this), value, deadline, v, r, s); (amountToken, amountETH) = removeLiquidityETH(token, liquidity, amountTokenMin, amountETHMin, to, deadline); } // **** REMOVE LIQUIDITY (supporting fee-on-transfer tokens) **** function removeLiquidityETHSupportingFeeOnTransferTokens( address token, uint liquidity, uint amountTokenMin, uint amountETHMin, address to, uint deadline ) public virtual override ensure(deadline) returns (uint amountETH) { (, amountETH) = removeLiquidity( token, WETH, liquidity, amountTokenMin, amountETHMin, address(this), deadline ); TransferHelper.safeTransfer(token, to, IERC20(token).balanceOf(address(this))); IWETH(WETH).withdraw(amountETH); TransferHelper.safeTransferETH(to, amountETH); } function removeLiquidityETHWithPermitSupportingFeeOnTransferTokens( address token, uint liquidity, uint amountTokenMin, uint amountETHMin, address to, uint deadline, bool approveMax, uint8 v, bytes32 r, bytes32 s ) external virtual override returns (uint amountETH) { address pair = UniswapV2Library.pairFor(factory, token, WETH); uint value = approveMax ? uint(-1) : liquidity; IUniswapV2Pair(pair).permit(msg.sender, address(this), value, deadline, v, r, s); amountETH = removeLiquidityETHSupportingFeeOnTransferTokens( token, liquidity, amountTokenMin, amountETHMin, to, deadline ); } /* // **** SWAP **** // requires the initial amount to have already been sent to the first pair function _swap(uint[] memory amounts, address[] memory path, address _to) internal virtual { for (uint i; i < path.length - 1; i++) { (address input, address output) = (path[i], path[i + 1]); (address token0,) = UniswapV2Library.sortTokens(input, output); uint amountOut = amounts[i + 1]; (uint amount0Out, uint amount1Out) = input == token0 ? (uint(0), amountOut) : (amountOut, uint(0)); address to = i < path.length - 2 ? UniswapV2Library.pairFor(factory, output, path[i + 2]) : _to; IUniswapV2Pair(UniswapV2Library.pairFor(factory, input, output)).swap( amount0Out, amount1Out, to, new bytes(0) ); } } function swapExactTokensForTokens( uint amountIn, uint amountOutMin, address[] calldata path, address to, uint deadline ) external virtual override ensure(deadline) returns (uint[] memory amounts) { amounts = UniswapV2Library.getAmountsOut(factory, amountIn, path); require(amounts[amounts.length - 1] >= amountOutMin, 'UniswapV2Router: INSUFFICIENT_OUTPUT_AMOUNT'); TransferHelper.safeTransferFrom( path[0], msg.sender, UniswapV2Library.pairFor(factory, path[0], path[1]), amounts[0] ); _swap(amounts, path, to); } function swapTokensForExactTokens( uint amountOut, uint amountInMax, address[] calldata path, address to, uint deadline ) external virtual override ensure(deadline) returns (uint[] memory amounts) { amounts = UniswapV2Library.getAmountsIn(factory, amountOut, path); require(amounts[0] <= amountInMax, 'UniswapV2Router: EXCESSIVE_INPUT_AMOUNT'); TransferHelper.safeTransferFrom( path[0], msg.sender, UniswapV2Library.pairFor(factory, path[0], path[1]), amounts[0] ); _swap(amounts, path, to); } function swapExactETHForTokens(uint amountOutMin, address[] calldata path, address to, uint deadline) external virtual override payable ensure(deadline) returns (uint[] memory amounts) { require(path[0] == WETH, 'UniswapV2Router: INVALID_PATH'); amounts = UniswapV2Library.getAmountsOut(factory, msg.value, path); require(amounts[amounts.length - 1] >= amountOutMin, 'UniswapV2Router: INSUFFICIENT_OUTPUT_AMOUNT'); IWETH(WETH).deposit{value: amounts[0]}(); assert(IWETH(WETH).transfer(UniswapV2Library.pairFor(factory, path[0], path[1]), amounts[0])); _swap(amounts, path, to); } function swapTokensForExactETH(uint amountOut, uint amountInMax, address[] calldata path, address to, uint deadline) external virtual override ensure(deadline) returns (uint[] memory amounts) { require(path[path.length - 1] == WETH, 'UniswapV2Router: INVALID_PATH'); amounts = UniswapV2Library.getAmountsIn(factory, amountOut, path); require(amounts[0] <= amountInMax, 'UniswapV2Router: EXCESSIVE_INPUT_AMOUNT'); TransferHelper.safeTransferFrom( path[0], msg.sender, UniswapV2Library.pairFor(factory, path[0], path[1]), amounts[0] ); _swap(amounts, path, address(this)); IWETH(WETH).withdraw(amounts[amounts.length - 1]); TransferHelper.safeTransferETH(to, amounts[amounts.length - 1]); } function swapExactTokensForETH(uint amountIn, uint amountOutMin, address[] calldata path, address to, uint deadline) external virtual override ensure(deadline) returns (uint[] memory amounts) { require(path[path.length - 1] == WETH, 'UniswapV2Router: INVALID_PATH'); amounts = UniswapV2Library.getAmountsOut(factory, amountIn, path); require(amounts[amounts.length - 1] >= amountOutMin, 'UniswapV2Router: INSUFFICIENT_OUTPUT_AMOUNT'); TransferHelper.safeTransferFrom( path[0], msg.sender, UniswapV2Library.pairFor(factory, path[0], path[1]), amounts[0] ); _swap(amounts, path, address(this)); IWETH(WETH).withdraw(amounts[amounts.length - 1]); TransferHelper.safeTransferETH(to, amounts[amounts.length - 1]); } function swapETHForExactTokens(uint amountOut, address[] calldata path, address to, uint deadline) external virtual override payable ensure(deadline) returns (uint[] memory amounts) { require(path[0] == WETH, 'UniswapV2Router: INVALID_PATH'); amounts = UniswapV2Library.getAmountsIn(factory, amountOut, path); require(amounts[0] <= msg.value, 'UniswapV2Router: EXCESSIVE_INPUT_AMOUNT'); IWETH(WETH).deposit{value: amounts[0]}(); assert(IWETH(WETH).transfer(UniswapV2Library.pairFor(factory, path[0], path[1]), amounts[0])); _swap(amounts, path, to); // refund dust eth, if any if (msg.value > amounts[0]) TransferHelper.safeTransferETH(msg.sender, msg.value - amounts[0]); } // **** SWAP (supporting fee-on-transfer tokens) **** // requires the initial amount to have already been sent to the first pair function _swapSupportingFeeOnTransferTokens(address[] memory path, address _to) internal virtual { for (uint i; i < path.length - 1; i++) { (address input, address output) = (path[i], path[i + 1]); (address token0,) = UniswapV2Library.sortTokens(input, output); IUniswapV2Pair pair = IUniswapV2Pair(UniswapV2Library.pairFor(factory, input, output)); uint amountInput; uint amountOutput; { // scope to avoid stack too deep errors (uint reserve0, uint reserve1,) = pair.getReserves(); (uint reserveInput, uint reserveOutput) = input == token0 ? (reserve0, reserve1) : (reserve1, reserve0); amountInput = IERC20(input).balanceOf(address(pair)).sub(reserveInput); amountOutput = UniswapV2Library.getAmountOut(amountInput, reserveInput, reserveOutput); } (uint amount0Out, uint amount1Out) = input == token0 ? (uint(0), amountOutput) : (amountOutput, uint(0)); address to = i < path.length - 2 ? UniswapV2Library.pairFor(factory, output, path[i + 2]) : _to; pair.swap(amount0Out, amount1Out, to, new bytes(0)); } } function swapExactTokensForTokensSupportingFeeOnTransferTokens( uint amountIn, uint amountOutMin, address[] calldata path, address to, uint deadline ) external virtual override ensure(deadline) { TransferHelper.safeTransferFrom( path[0], msg.sender, UniswapV2Library.pairFor(factory, path[0], path[1]), amountIn ); uint balanceBefore = IERC20(path[path.length - 1]).balanceOf(to); _swapSupportingFeeOnTransferTokens(path, to); require( IERC20(path[path.length - 1]).balanceOf(to).sub(balanceBefore) >= amountOutMin, 'UniswapV2Router: INSUFFICIENT_OUTPUT_AMOUNT' ); } function swapExactETHForTokensSupportingFeeOnTransferTokens( uint amountOutMin, address[] calldata path, address to, uint deadline ) external virtual override payable ensure(deadline) { require(path[0] == WETH, 'UniswapV2Router: INVALID_PATH'); uint amountIn = msg.value; IWETH(WETH).deposit{value: amountIn}(); assert(IWETH(WETH).transfer(UniswapV2Library.pairFor(factory, path[0], path[1]), amountIn)); uint balanceBefore = IERC20(path[path.length - 1]).balanceOf(to); _swapSupportingFeeOnTransferTokens(path, to); require( IERC20(path[path.length - 1]).balanceOf(to).sub(balanceBefore) >= amountOutMin, 'UniswapV2Router: INSUFFICIENT_OUTPUT_AMOUNT' ); } function swapExactTokensForETHSupportingFeeOnTransferTokens( uint amountIn, uint amountOutMin, address[] calldata path, address to, uint deadline ) external virtual override ensure(deadline) { require(path[path.length - 1] == WETH, 'UniswapV2Router: INVALID_PATH'); TransferHelper.safeTransferFrom( path[0], msg.sender, UniswapV2Library.pairFor(factory, path[0], path[1]), amountIn ); _swapSupportingFeeOnTransferTokens(path, address(this)); uint amountOut = IERC20(WETH).balanceOf(address(this)); require(amountOut >= amountOutMin, 'UniswapV2Router: INSUFFICIENT_OUTPUT_AMOUNT'); IWETH(WETH).withdraw(amountOut); TransferHelper.safeTransferETH(to, amountOut); } */ // **** LIBRARY FUNCTIONS **** function quote(uint amountA, uint reserveA, uint reserveB) public pure virtual override returns (uint amountB) { return UniswapV2Library.quote(amountA, reserveA, reserveB); } function getAmountOut(uint amountIn, uint reserveIn, uint reserveOut) public pure virtual override returns (uint amountOut) { return UniswapV2Library.getAmountOut(amountIn, reserveIn, reserveOut); } function getAmountIn(uint amountOut, uint reserveIn, uint reserveOut) public pure virtual override returns (uint amountIn) { return UniswapV2Library.getAmountIn(amountOut, reserveIn, reserveOut); } function getAmountsOut(uint amountIn, address[] memory path) public view virtual override returns (uint[] memory amounts) { return UniswapV2Library.getAmountsOut(factory, amountIn, path); } function getAmountsIn(uint amountOut, address[] memory path) public view virtual override returns (uint[] memory amounts) { return UniswapV2Library.getAmountsIn(factory, amountOut, path); } }
您需要
init_code_hash使用新部署的 Factory 合約來創建。Uniswap 的 Github 儲存庫中硬編碼的這個地址專門用於他們在乙太坊網路中的部署。
在您的
UniswapV2Factory.sol程式碼中，添加以下程式碼。bytes32 public constant INIT_CODE_PAIR_HASH = keccak256(abi.encodePacked(type(UniswapV2Pair).creationCode));部署後，使用 remix 或 truffle 控制台呼叫它以獲取值。
UniswapV2Library然後在部署路由器之前將此值替換為您的值。
這個初始化程式碼雜湊是這樣計算的：
keccak256(abi.encodePacked(type(PairContract).creationCode));