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Diffstat (limited to 'contracts/extensions/contracts/src/OrderMatcher/MixinAssets.sol')
| -rw-r--r-- | contracts/extensions/contracts/src/OrderMatcher/MixinAssets.sol | 195 |
1 files changed, 195 insertions, 0 deletions
diff --git a/contracts/extensions/contracts/src/OrderMatcher/MixinAssets.sol b/contracts/extensions/contracts/src/OrderMatcher/MixinAssets.sol new file mode 100644 index 000000000..65b36ea65 --- /dev/null +++ b/contracts/extensions/contracts/src/OrderMatcher/MixinAssets.sol @@ -0,0 +1,195 @@ +/* + + 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; + +import "@0x/contracts-utils/contracts/src/LibBytes.sol"; +import "@0x/contracts-utils/contracts/src/Ownable.sol"; +import "@0x/contracts-erc20/contracts/src/interfaces/IERC20Token.sol"; +import "@0x/contracts-erc721/contracts/src/interfaces/IERC721Token.sol"; +import "./mixins/MAssets.sol"; +import "./libs/LibConstants.sol"; + + +contract MixinAssets is + MAssets, + Ownable, + LibConstants +{ + using LibBytes for bytes; + + /// @dev Withdraws assets from this contract. The contract requires a ZRX balance in order to + /// function optimally, and this function allows the ZRX to be withdrawn by owner. It may also be + /// used to withdraw assets that were accidentally sent to this contract. + /// @param assetData Byte array encoded for the respective asset proxy. + /// @param amount Amount of asset to withdraw. + function withdrawAsset( + bytes assetData, + uint256 amount + ) + external + onlyOwner + { + transferAssetToSender(assetData, amount); + } + + /// @dev Approves or disapproves an AssetProxy to spend asset. + /// @param assetData Byte array encoded for the respective asset proxy. + /// @param amount Amount of asset to approve for respective proxy. + function approveAssetProxy( + bytes assetData, + uint256 amount + ) + external + onlyOwner + { + bytes4 proxyId = assetData.readBytes4(0); + + if (proxyId == ERC20_DATA_ID) { + approveERC20Token(assetData, amount); + } else if (proxyId == ERC721_DATA_ID) { + approveERC721Token(assetData, amount); + } else { + revert("UNSUPPORTED_ASSET_PROXY"); + } + } + + /// @dev Transfers given amount of asset to sender. + /// @param assetData Byte array encoded for the respective asset proxy. + /// @param amount Amount of asset to transfer to sender. + function transferAssetToSender( + bytes memory assetData, + uint256 amount + ) + internal + { + bytes4 proxyId = assetData.readBytes4(0); + + if (proxyId == ERC20_DATA_ID) { + transferERC20Token(assetData, amount); + } else if (proxyId == ERC721_DATA_ID) { + transferERC721Token(assetData, amount); + } else { + revert("UNSUPPORTED_ASSET_PROXY"); + } + } + + /// @dev Decodes ERC20 assetData and transfers given amount to sender. + /// @param assetData Byte array encoded for the respective asset proxy. + /// @param amount Amount of asset to transfer to sender. + function transferERC20Token( + bytes memory assetData, + uint256 amount + ) + internal + { + // 4 byte id + 12 0 bytes before ABI encoded token address. + address token = assetData.readAddress(16); + + // Transfer tokens. + // We do a raw call so we can check the success separate + // from the return data. + bool success = token.call(abi.encodeWithSelector( + ERC20_TRANSFER_SELECTOR, + msg.sender, + amount + )); + require( + success, + "TRANSFER_FAILED" + ); + + // Check return data. + // If there is no return data, we assume the token incorrectly + // does not return a bool. In this case we expect it to revert + // on failure, which was handled above. + // If the token does return data, we require that it is a single + // value that evaluates to true. + assembly { + if returndatasize { + success := 0 + if eq(returndatasize, 32) { + // First 64 bytes of memory are reserved scratch space + returndatacopy(0, 0, 32) + success := mload(0) + } + } + } + require( + success, + "TRANSFER_FAILED" + ); + } + + /// @dev Decodes ERC721 assetData and transfers given amount to sender. + /// @param assetData Byte array encoded for the respective asset proxy. + /// @param amount Amount of asset to transfer to sender. + function transferERC721Token( + bytes memory assetData, + uint256 amount + ) + internal + { + require( + amount == 1, + "INVALID_AMOUNT" + ); + // Decode asset data. + // 4 byte id + 12 0 bytes before ABI encoded token address. + address token = assetData.readAddress(16); + // 4 byte id + 32 byte ABI encoded token address before token id. + uint256 tokenId = assetData.readUint256(36); + + // Perform transfer. + IERC721Token(token).transferFrom( + address(this), + msg.sender, + tokenId + ); + } + + /// @dev Sets approval for ERC20 AssetProxy. + /// @param assetData Byte array encoded for the respective asset proxy. + /// @param amount Amount of asset to approve for respective proxy. + function approveERC20Token( + bytes memory assetData, + uint256 amount + ) + internal + { + address token = assetData.readAddress(16); + require( + IERC20Token(token).approve(ERC20_PROXY_ADDRESS, amount), + "APPROVAL_FAILED" + ); + } + + /// @dev Sets approval for ERC721 AssetProxy. + /// @param assetData Byte array encoded for the respective asset proxy. + /// @param amount Amount of asset to approve for respective proxy. + function approveERC721Token( + bytes memory assetData, + uint256 amount + ) + internal + { + address token = assetData.readAddress(16); + bool approval = amount >= 1; + IERC721Token(token).setApprovalForAll(ERC721_PROXY_ADDRESS, approval); + } +} |