forked from farcasterxyz/contracts
-
Notifications
You must be signed in to change notification settings - Fork 0
/
FnameResolver.sol
208 lines (175 loc) · 7.7 KB
/
FnameResolver.sol
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
// SPDX-License-Identifier: MIT
pragma solidity 0.8.21;
import {Ownable2Step} from "openzeppelin/contracts/access/Ownable2Step.sol";
import {ECDSA} from "openzeppelin/contracts/utils/cryptography/ECDSA.sol";
import {ERC165} from "openzeppelin/contracts/utils/introspection/ERC165.sol";
import {EIP712} from "./abstract/EIP712.sol";
interface IAddressQuery {
function addr(bytes32 node) external view returns (address);
}
interface IExtendedResolver {
function resolve(bytes memory name, bytes memory data) external view returns (bytes memory);
}
interface IResolverService {
function resolve(
bytes calldata name,
bytes calldata data
) external view returns (string memory fname, uint256 timestamp, address owner, bytes memory signature);
}
/**
* @title Farcaster FnameResolver
*
* @notice See https://github.com/farcasterxyz/contracts/blob/v3.1.0/docs/docs.md for an overview.
*
* @custom:security-contact [email protected]
*/
contract FnameResolver is IExtendedResolver, EIP712, ERC165, Ownable2Step {
/*//////////////////////////////////////////////////////////////
ERRORS
//////////////////////////////////////////////////////////////*/
/**
* @dev Revert to indicate an offchain CCIP lookup. See: https://eips.ethereum.org/EIPS/eip-3668
*
* @param sender Address of this contract.
* @param urls List of lookup gateway URLs.
* @param callData Data to call the gateway with.
* @param callbackFunction 4 byte function selector of the callback function on this contract.
* @param extraData Additional data required by the callback function.
*/
error OffchainLookup(address sender, string[] urls, bytes callData, bytes4 callbackFunction, bytes extraData);
/// @dev Revert queries for unimplemented resolver functions.
error ResolverFunctionNotSupported();
/// @dev Revert if the recovered signer address is not an authorized signer.
error InvalidSigner();
/*//////////////////////////////////////////////////////////////
EVENTS
//////////////////////////////////////////////////////////////*/
/**
* @dev Emit an event when the contract owner authorizes a new signer.
*
* @param signer Address of the authorized signer.
*/
event AddSigner(address indexed signer);
/**
* @dev Emit an event when the contract owner removes an authorized signer.
*
* @param signer Address of the removed signer.
*/
event RemoveSigner(address indexed signer);
/*//////////////////////////////////////////////////////////////
CONSTANTS
//////////////////////////////////////////////////////////////*/
/**
* @dev Contract version specified using Farcaster protocol version scheme.
*/
string public constant VERSION = "2023.08.23";
/**
* @dev EIP-712 typehash of the UsernameProof struct.
*/
bytes32 public constant USERNAME_PROOF_TYPEHASH =
keccak256("UserNameProof(string name,uint256 timestamp,address owner)");
/*//////////////////////////////////////////////////////////////
PARAMETERS
//////////////////////////////////////////////////////////////*/
/**
* @dev URL of the CCIP lookup gateway.
*/
string public url;
/**
* @dev Mapping of signer address to authorized boolean.
*/
mapping(address signer => bool isAuthorized) public signers;
/*//////////////////////////////////////////////////////////////
CONSTRUCTOR
//////////////////////////////////////////////////////////////*/
/**
* @notice Set the lookup gateway URL and initial signer.
*
* @param _url Lookup gateway URL. This value is set permanently.
* @param _signer Initial authorized signer address.
* @param _initialOwner Initial owner address.
*/
constructor(
string memory _url,
address _signer,
address _initialOwner
) EIP712("Farcaster name verification", "1") {
_transferOwnership(_initialOwner);
url = _url;
signers[_signer] = true;
emit AddSigner(_signer);
}
/*//////////////////////////////////////////////////////////////
RESOLVER VIEWS
//////////////////////////////////////////////////////////////*/
/**
* @notice Resolve the provided ENS name. This function will always revert to indicate an
* offchain lookup.
*
* @param name DNS-encoded name to resolve.
* @param data Encoded calldata of an ENS resolver function. This resolver supports only
* address resolution (Signature 0x3b3b57de). Calling the CCIP gateway with any
* other resolver function will revert.
*/
function resolve(bytes calldata name, bytes calldata data) external view returns (bytes memory) {
if (bytes4(data[:4]) != IAddressQuery.addr.selector) {
revert ResolverFunctionNotSupported();
}
bytes memory callData = abi.encodeCall(IResolverService.resolve, (name, data));
string[] memory urls = new string[](1);
urls[0] = url;
revert OffchainLookup(address(this), urls, callData, this.resolveWithProof.selector, callData);
}
/**
* @notice Offchain lookup callback. The caller must provide the signed response returned by
* the lookup gateway.
*
* @param response Response from the CCIP gateway which has the following ABI-encoded fields:
* - string: Fname of the username proof.
* - uint256: Timestamp of the username proof.
* - address: Owner address that signed the username proof.
* - bytes: EIP-712 signature provided by the CCIP gateway server.
*
* @return ABI-encoded address of the fname owner.
*/
function resolveWithProof(
bytes calldata response,
bytes calldata /* extraData */
) external view returns (bytes memory) {
(string memory fname, uint256 timestamp, address fnameOwner, bytes memory signature) =
abi.decode(response, (string, uint256, address, bytes));
bytes32 proofHash =
keccak256(abi.encode(USERNAME_PROOF_TYPEHASH, keccak256(bytes(fname)), timestamp, fnameOwner));
bytes32 eip712hash = _hashTypedDataV4(proofHash);
address signer = ECDSA.recover(eip712hash, signature);
if (!signers[signer]) revert InvalidSigner();
return abi.encode(fnameOwner);
}
/*//////////////////////////////////////////////////////////////
PERMISSIONED ACTIONS
//////////////////////////////////////////////////////////////*/
/**
* @notice Add a signer address to the authorized mapping. Only callable by owner.
*
* @param signer The signer address.
*/
function addSigner(address signer) external onlyOwner {
signers[signer] = true;
emit AddSigner(signer);
}
/**
* @notice Remove a signer address from the authorized mapping. Only callable by owner.
*
* @param signer The signer address.
*/
function removeSigner(address signer) external onlyOwner {
signers[signer] = false;
emit RemoveSigner(signer);
}
/*//////////////////////////////////////////////////////////////
INTERFACE DETECTION
//////////////////////////////////////////////////////////////*/
function supportsInterface(bytes4 interfaceId) public view override returns (bool) {
return interfaceId == type(IExtendedResolver).interfaceId || super.supportsInterface(interfaceId);
}
}