Gasless Asks Extension

contracts/ZoraModuleManager.sol

@@ -3,6 +3,13 @@ pragma solidity 0.8.10;
 
 import {ZoraProtocolFeeSettings} from "./auxiliary/ZoraProtocolFeeSettings/ZoraProtocolFeeSettings.sol";
 
+struct ModuleApprovalSig {
+    uint8 v; // The 129th byte and chain ID of the signature
+    bytes32 r; // The first 64 bytes of the signature
+    bytes32 s; // Bytes 64-128 of the signature
+    uint256 deadline; // The deadline at which point the approval expires
+}
+
 /// @title ZoraModuleManager
 /// @author tbtstl <[email protected]>
 /// @notice This contract allows users to approve registered modules on ZORA V3

contracts/modules/Asks/Core/ETH/GaslessAsksCoreEth.sol

@@ -0,0 +1,202 @@
+// SPDX-License-Identifier: GPL-3.0
+pragma solidity 0.8.10;
+
+import {ReentrancyGuard} from "@rari-capital/solmate/src/utils/ReentrancyGuard.sol";
+import {IERC721} from "@openzeppelin/contracts/token/ERC721/IERC721.sol";
+
+import {ZoraModuleManager} from "../../../../ZoraModuleManager.sol";
+import {FeePayoutSupportV1} from "../../../../common/FeePayoutSupport/FeePayoutSupportV1.sol";
+import {ModuleNamingSupportV1} from "../../../../common/ModuleNamingSupport/ModuleNamingSupportV1.sol";
+import {IGaslessAsksCoreEth} from "./IGaslessAsksCoreEth.sol";
+import {AsksCoreEth} from "./AsksCoreEth.sol";
+
+/// @title Gasless Asks Core ETH
+/// @author tbtstl
+/// @notice Extension to minimal ETH asks module, providing off-chain order support
+contract GaslessAsksCoreEth is IGaslessAsksCoreEth, ReentrancyGuard, FeePayoutSupportV1, ModuleNamingSupportV1 {
+    ///                                                          ///
+    ///                        IMMUTABLES                        ///
+    ///                                                          ///
+
+    ZoraModuleManager private immutable zmm;
+    AsksCoreEth private immutable asksModule;
+
+    /// @notice The EIP-712 domain separator
+    bytes32 private immutable EIP_712_DOMAIN_SEPARATOR =
+        keccak256(
+            abi.encode(
+                keccak256("EIP712Domain(string name,string version,uint256 chainId,address verifyingContract)"),
+                keccak256(bytes("ZORA:GaslessAsksCoreEth")),
+                keccak256(bytes("1")),
+                _chainID(),
+                address(this)
+            )
+        );
+
+    /// @notice The EIP-712 type for a signed ask order
+    /// @dev keccak256("SignedAsk(address tokenAddress,uint256 tokenId,uint256 expiry,uint256 nonce, uint256 amount,uint8 _v,bytes32 _r,bytes32 _s,uint256 deadline)")
+    bytes32 private constant SIGNED_ASK_TYPEHASH = 0x324d0f7b7aa4e0f218259028fc60b98a32657c974f8cb44eb3ceadbec042ddc4;
+
+    ///                                                          ///
+    ///                        ASK STORAGE                       ///
+    ///                                                          ///
+
+    /// @notice The spent (canceled or executed) asks
+    /// @dev ERC-721 token contract => ERC-721 token id => Ask signer => spent boolean
+    mapping(address => mapping(uint256 => mapping(address => bool))) public spentAsks;
+
+    /// @param _zmm The ZORA Module Manager address
+    /// @param _asksModule The ZORA Asks Core ETH Module address
+    /// @param _royaltyEngine The Manifold Royalty Engine address
+    /// @param _protocolFeeSettings The ZORA Protocol Fee Settings address
+    /// @param _weth The WETH token address
+    // TODO we don't even need this to be a "module" since no transfer helpers are used here
+    constructor(
+        address _zmm,
+        address _asksModule,
+        address _royaltyEngine,
+        address _protocolFeeSettings,
+        address _weth
+    )
+        FeePayoutSupportV1(_royaltyEngine, _protocolFeeSettings, _weth, ZoraModuleManager(_zmm).registrar())
+        ModuleNamingSupportV1("Gasless Asks Core ETH")
+    {
+        zmm = ZoraModuleManager(_zmm);
+        asksModule = AsksCoreEth(_asksModule);
+    }
+
+    /// @notice Implements EIP-165 for standard interface detection
+    /// @dev `0x01ffc9a7` is the IERC165 interface id
+    /// @param _interfaceId The identifier of a given interface
+    /// @return If the given interface is supported
+    function supportsInterface(bytes4 _interfaceId) external pure returns (bool) {
+        return _interfaceId == type(IGaslessAsksCoreEth).interfaceId || _interfaceId == 0x01ffc9a7;
+    }
+
+    /// @notice Executes a signed order on the Asks module
+    /// @param _ask The signed ask parameters to execute
+    /// @param _v The 129th byte and chain ID of the signature
+    /// @param _r The first 64 bytes of the signature
+    /// @param _s Bytes 64-128 of the signature
+    function executeAsk(
+        IGaslessAsksCoreEth.GaslessAsk calldata _ask,
+        uint8 _v,
+        bytes32 _r,
+        bytes32 _s
+    ) external payable nonReentrant {
+        require(_ask.expiry == 0 || _ask.expiry >= block.timestamp, "EXPIRED_ASK");
+        address recoveredAddress = _recoverAddress(_ask, _v, _r, _s);
+        require(recoveredAddress != address(0) && recoveredAddress == _ask.from, "INVALID_SIG");
+        require(!spentAsks[_ask.tokenAddress][_ask.tokenId][_ask.from], "SPENT_ASK");
+
+        if (!zmm.isModuleApproved(_ask.from, address(asksModule))) {
+            zmm.setApprovalForModuleBySig(
+                address(asksModule),
+                _ask.from,
+                true,
+                _ask.approvalSig.deadline,
+                _ask.approvalSig.v,
+                _ask.approvalSig.r,
+                _ask.approvalSig.s
+            );
+        }
+
+        asksModule.createAsk(_ask.tokenAddress, _ask.tokenId, _ask.amount);
+        asksModule.fillAsk{value: msg.value}(_ask.tokenAddress, _ask.tokenId);
+        spentAsks[_ask.tokenAddress][_ask.tokenId][_ask.from] = true;
+
+        IERC721(_ask.tokenAddress).transferFrom(address(this), msg.sender, _ask.tokenId);
+    }
+
+    /// @notice Creates an on-chain order on the Asks module
+    /// @param _ask The signed ask parameters to store
+    /// @param _v The 129th byte and chain ID of the signature
+    /// @param _r The first 64 bytes of the signature
+    /// @param _s Bytes 64-128 of the signature
+    function storeAsk(
+        IGaslessAsksCoreEth.GaslessAsk calldata _ask,
+        uint8 _v,
+        bytes32 _r,
+        bytes32 _s
+    ) external nonReentrant {
+        require(_ask.expiry == 0 || _ask.expiry >= block.timestamp, "EXPIRED_ASK");
+        address recoveredAddress = _recoverAddress(_ask, _v, _r, _s);
+        require(recoveredAddress != address(0) && recoveredAddress == _ask.from, "INVALID_SIG");
+
+        asksModule.createAsk(_ask.tokenAddress, _ask.tokenId, _ask.amount);
+    }
+
+    /// @notice Broadcasts an on-chain order to indexers
+    /// @dev Intentionally a no-op, this can be picked up via EVM traces :)
+    /// @param _ask The signed ask parameters to broadcast
+    /// @param _v The 129th byte and chain ID of the signature
+    /// @param _r The first 64 bytes of the signature
+    /// @param _s Bytes 64-128 of the signature
+    function broadcastAsk(
+        IGaslessAsksCoreEth.GaslessAsk calldata _ask,
+        uint8 _v,
+        bytes32 _r,
+        bytes32 _s
+    ) external {
+        // noop :)
+    }
+
+    /// @notice Invalidates an off-chain order
+    /// @param _ask The signed ask parameters to invalidate
+    function cancelAsk(IGaslessAsksCoreEth.GaslessAsk calldata _ask) external nonReentrant {
+        require(msg.sender == _ask.from, "ONLY_SIGNER");
+
+        spentAsks[_ask.tokenAddress][_ask.tokenId][msg.sender] = true;
+    }
+
+    /// @notice Validates an on-chain order
+    /// @param _ask The signed ask parameters to validate
+    /// @param _v The 129th byte and chain ID of the signature
+    /// @param _r The first 64 bytes of the signature
+    /// @param _s Bytes 64-128 of the signature
+    function validateAskSig(
+        IGaslessAsksCoreEth.GaslessAsk calldata _ask,
+        uint8 _v,
+        bytes32 _r,
+        bytes32 _s
+    ) external view returns (bool) {
+        return _recoverAddress(_ask, _v, _r, _s) == _ask.from;
+    }
+
+    function _recoverAddress(
+        IGaslessAsksCoreEth.GaslessAsk calldata _ask,
+        uint8 _v,
+        bytes32 _r,
+        bytes32 _s
+    ) private view returns (address) {
+        bytes32 digest = keccak256(
+            abi.encodePacked(
+                "\x19\x01",
+                EIP_712_DOMAIN_SEPARATOR,
+                keccak256(
+                    abi.encode(
+                        SIGNED_ASK_TYPEHASH,
+                        _ask.tokenAddress,
+                        _ask.tokenId,
+                        _ask.expiry,
+                        _ask.nonce,
+                        _ask.amount,
+                        _ask.approvalSig.v,
+                        _ask.approvalSig.r,
+                        _ask.approvalSig.s,
+                        _ask.approvalSig.deadline
+                    )
+                )
+            )
+        );
+
+        return ecrecover(digest, _v, _r, _s);
+    }
+
+    /// @notice The EIP-155 chain id
+    function _chainID() private view returns (uint256 id) {
+        assembly {
+            id := chainid()
+        }
+    }
+}

contracts/modules/Asks/Core/ETH/IGaslessAsksCoreEth.sol

@@ -0,0 +1,46 @@
+// SPDX-License-Identifier: GPL-3.0
+pragma solidity 0.8.10;
+
+import {ModuleApprovalSig} from "../../../../ZoraModuleManager.sol";
+
+interface IGaslessAsksCoreEth {
+    struct GaslessAsk {
+        address from; // The address of the seller
+        address tokenAddress; // The address of the NFT being sold
+        uint256 tokenId; // The ID of the NFT being sold
+        uint256 expiry; // The Unix timestamp that this order expires at
+        uint256 nonce; // Nonce to represent this order (for cancellations)
+        uint256 amount; // The amount of ETH to sell the NFT for
+        ModuleApprovalSig approvalSig; // The user's approval to use this module (optional, empty if already set)
+    }
+
+    function executeAsk(
+        GaslessAsk calldata _ask,
+        uint8 _v,
+        bytes32 _r,
+        bytes32 _s
+    ) external payable;
+
+    function storeAsk(
+        GaslessAsk calldata _ask,
+        uint8 _v,
+        bytes32 _r,
+        bytes32 _s
+    ) external;
+
+    function broadcastAsk(
+        GaslessAsk calldata _ask,
+        uint8 _v,
+        bytes32 _r,
+        bytes32 _s
+    ) external;
+
+    function cancelAsk(GaslessAsk calldata _ask) external;
+
+    function validateAskSig(
+        GaslessAsk calldata _ask,
+        uint8 _v,
+        bytes32 _r,
+        bytes32 _s
+    ) external view returns (bool);
+}