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Diffstat (limited to 'contracts/extensions/contracts/src/OrderValidator/OrderValidator.sol')
| -rw-r--r-- | contracts/extensions/contracts/src/OrderValidator/OrderValidator.sol | 218 |
1 files changed, 218 insertions, 0 deletions
diff --git a/contracts/extensions/contracts/src/OrderValidator/OrderValidator.sol b/contracts/extensions/contracts/src/OrderValidator/OrderValidator.sol new file mode 100644 index 000000000..3297a980f --- /dev/null +++ b/contracts/extensions/contracts/src/OrderValidator/OrderValidator.sol @@ -0,0 +1,218 @@ +/* + + Copyright 2018 ZeroEx Intl. + + Licensed under the Apache License, Version 2.0 (the "License"); + you may not use this file except in compliance with the License. + You may obtain a copy of the License at + + http://www.apache.org/licenses/LICENSE-2.0 + + Unless required by applicable law or agreed to in writing, software + distributed under the License is distributed on an "AS IS" BASIS, + WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. + See the License for the specific language governing permissions and + limitations under the License. + +*/ + +pragma solidity 0.4.24; +pragma experimental ABIEncoderV2; + +import "@0x/contracts-exchange/contracts/src/interfaces/IExchange.sol"; +import "@0x/contracts-exchange-libs/contracts/src/LibOrder.sol"; +import "@0x/contracts-erc20/contracts/src/interfaces/IERC20Token.sol"; +import "@0x/contracts-erc721/contracts/src/interfaces/IERC721Token.sol"; +import "@0x/contracts-utils/contracts/src/LibBytes.sol"; + + +contract OrderValidator { + + using LibBytes for bytes; + + bytes4 constant internal ERC20_DATA_ID = bytes4(keccak256("ERC20Token(address)")); + bytes4 constant internal ERC721_DATA_ID = bytes4(keccak256("ERC721Token(address,uint256)")); + + struct TraderInfo { + uint256 makerBalance; // Maker's balance of makerAsset + uint256 makerAllowance; // Maker's allowance to corresponding AssetProxy + uint256 takerBalance; // Taker's balance of takerAsset + uint256 takerAllowance; // Taker's allowance to corresponding AssetProxy + uint256 makerZrxBalance; // Maker's balance of ZRX + uint256 makerZrxAllowance; // Maker's allowance of ZRX to ERC20Proxy + uint256 takerZrxBalance; // Taker's balance of ZRX + uint256 takerZrxAllowance; // Taker's allowance of ZRX to ERC20Proxy + } + + // solhint-disable var-name-mixedcase + IExchange internal EXCHANGE; + bytes internal ZRX_ASSET_DATA; + // solhint-enable var-name-mixedcase + + constructor (address _exchange, bytes memory _zrxAssetData) + public + { + EXCHANGE = IExchange(_exchange); + ZRX_ASSET_DATA = _zrxAssetData; + } + + /// @dev Fetches information for order and maker/taker of order. + /// @param order The order structure. + /// @param takerAddress Address that will be filling the order. + /// @return OrderInfo and TraderInfo instances for given order. + function getOrderAndTraderInfo(LibOrder.Order memory order, address takerAddress) + public + view + returns (LibOrder.OrderInfo memory orderInfo, TraderInfo memory traderInfo) + { + orderInfo = EXCHANGE.getOrderInfo(order); + traderInfo = getTraderInfo(order, takerAddress); + return (orderInfo, traderInfo); + } + + /// @dev Fetches information for all passed in orders and the makers/takers of each order. + /// @param orders Array of order specifications. + /// @param takerAddresses Array of taker addresses corresponding to each order. + /// @return Arrays of OrderInfo and TraderInfo instances that correspond to each order. + function getOrdersAndTradersInfo(LibOrder.Order[] memory orders, address[] memory takerAddresses) + public + view + returns (LibOrder.OrderInfo[] memory ordersInfo, TraderInfo[] memory tradersInfo) + { + ordersInfo = EXCHANGE.getOrdersInfo(orders); + tradersInfo = getTradersInfo(orders, takerAddresses); + return (ordersInfo, tradersInfo); + } + + /// @dev Fetches balance and allowances for maker and taker of order. + /// @param order The order structure. + /// @param takerAddress Address that will be filling the order. + /// @return Balances and allowances of maker and taker of order. + function getTraderInfo(LibOrder.Order memory order, address takerAddress) + public + view + returns (TraderInfo memory traderInfo) + { + (traderInfo.makerBalance, traderInfo.makerAllowance) = getBalanceAndAllowance(order.makerAddress, order.makerAssetData); + (traderInfo.takerBalance, traderInfo.takerAllowance) = getBalanceAndAllowance(takerAddress, order.takerAssetData); + bytes memory zrxAssetData = ZRX_ASSET_DATA; + (traderInfo.makerZrxBalance, traderInfo.makerZrxAllowance) = getBalanceAndAllowance(order.makerAddress, zrxAssetData); + (traderInfo.takerZrxBalance, traderInfo.takerZrxAllowance) = getBalanceAndAllowance(takerAddress, zrxAssetData); + return traderInfo; + } + + /// @dev Fetches balances and allowances of maker and taker for each provided order. + /// @param orders Array of order specifications. + /// @param takerAddresses Array of taker addresses corresponding to each order. + /// @return Array of balances and allowances for maker and taker of each order. + function getTradersInfo(LibOrder.Order[] memory orders, address[] memory takerAddresses) + public + view + returns (TraderInfo[] memory) + { + uint256 ordersLength = orders.length; + TraderInfo[] memory tradersInfo = new TraderInfo[](ordersLength); + for (uint256 i = 0; i != ordersLength; i++) { + tradersInfo[i] = getTraderInfo(orders[i], takerAddresses[i]); + } + return tradersInfo; + } + + /// @dev Fetches token balances and allowances of an address to given assetProxy. Supports ERC20 and ERC721. + /// @param target Address to fetch balances and allowances of. + /// @param assetData Encoded data that can be decoded by a specified proxy contract when transferring asset. + /// @return Balance of asset and allowance set to given proxy of asset. + /// For ERC721 tokens, these values will always be 1 or 0. + function getBalanceAndAllowance(address target, bytes memory assetData) + public + view + returns (uint256 balance, uint256 allowance) + { + bytes4 assetProxyId = assetData.readBytes4(0); + address token = assetData.readAddress(16); + address assetProxy = EXCHANGE.getAssetProxy(assetProxyId); + + if (assetProxyId == ERC20_DATA_ID) { + // Query balance + balance = IERC20Token(token).balanceOf(target); + + // Query allowance + allowance = IERC20Token(token).allowance(target, assetProxy); + } else if (assetProxyId == ERC721_DATA_ID) { + uint256 tokenId = assetData.readUint256(36); + + // Query owner of tokenId + address owner = getERC721TokenOwner(token, tokenId); + + // Set balance to 1 if tokenId is owned by target + balance = target == owner ? 1 : 0; + + // Check if ERC721Proxy is approved to spend tokenId + bool isApproved = IERC721Token(token).isApprovedForAll(target, assetProxy); + + // Set alowance to 1 if ERC721Proxy is approved to spend tokenId + allowance = isApproved ? 1 : 0; + } else { + revert("UNSUPPORTED_ASSET_PROXY"); + } + return (balance, allowance); + } + + /// @dev Fetches token balances and allowances of an address for each given assetProxy. Supports ERC20 and ERC721. + /// @param target Address to fetch balances and allowances of. + /// @param assetData Array of encoded byte arrays that can be decoded by a specified proxy contract when transferring asset. + /// @return Balances and allowances of assets. + /// For ERC721 tokens, these values will always be 1 or 0. + function getBalancesAndAllowances(address target, bytes[] memory assetData) + public + view + returns (uint256[] memory, uint256[] memory) + { + uint256 length = assetData.length; + uint256[] memory balances = new uint256[](length); + uint256[] memory allowances = new uint256[](length); + for (uint256 i = 0; i != length; i++) { + (balances[i], allowances[i]) = getBalanceAndAllowance(target, assetData[i]); + } + return (balances, allowances); + } + + /// @dev Calls `token.ownerOf(tokenId)`, but returns a null owner instead of reverting on an unowned token. + /// @param token Address of ERC721 token. + /// @param tokenId The identifier for the specific NFT. + /// @return Owner of tokenId or null address if unowned. + function getERC721TokenOwner(address token, uint256 tokenId) + public + view + returns (address owner) + { + assembly { + // load free memory pointer + let cdStart := mload(64) + + // bytes4(keccak256(ownerOf(uint256))) = 0x6352211e + mstore(cdStart, 0x6352211e00000000000000000000000000000000000000000000000000000000) + mstore(add(cdStart, 4), tokenId) + + // staticcall `ownerOf(tokenId)` + // `ownerOf` will revert if tokenId is not owned + let success := staticcall( + gas, // forward all gas + token, // call token contract + cdStart, // start of calldata + 36, // length of input is 36 bytes + cdStart, // write output over input + 32 // size of output is 32 bytes + ) + + // Success implies that tokenId is owned + // Copy owner from return data if successful + if success { + owner := mload(cdStart) + } + } + + // Owner initialized to address(0), no need to modify if call is unsuccessful + return owner; + } +} |