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
//SPDX-License-Identifier: MIT
pragma solidity 0.8.15;
import {
AdminFaucetAuthModule
} from "../../universal/faucet/authmodules/AdminFaucetAuthModule.sol";
import {
ECDSAUpgradeable
} from "@openzeppelin/contracts-upgradeable/utils/cryptography/ECDSAUpgradeable.sol";
/**
* Simple helper contract that helps with testing the Faucet contract.
*/
contract FaucetHelper {
/**
* @notice EIP712 typehash for the Proof type.
*/
bytes32 public constant PROOF_TYPEHASH =
keccak256("Proof(address recipient,bytes32 nonce,bytes32 id)");
/**
* @notice EIP712 typehash for the EIP712Domain type that is included as part of the signature.
*/
bytes32 public constant EIP712_DOMAIN_TYPEHASH =
keccak256(
"EIP712Domain(string name,string version,uint256 chainId,address verifyingContract)"
);
/**
* @notice Keeps track of current nonce to generate new nonces for each drip.
*/
uint256 public currentNonce;
/**
* @notice Returns a bytes32 nonce that should change everytime. In practice, people should use
* pseudorandom nonces.
*
* @return Nonce that should be used as part of drip parameters.
*/
function consumeNonce() public returns (bytes32) {
return bytes32(keccak256(abi.encode(currentNonce++)));
}
/**
* @notice Returns the hash of the struct Proof.
*
* @param _proof Proof struct to hash.
*
* @return EIP-712 typed struct hash.
*/
function getProofStructHash(AdminFaucetAuthModule.Proof memory _proof)
public
pure
returns (bytes32)
{
return keccak256(abi.encode(PROOF_TYPEHASH, _proof.recipient, _proof.nonce, _proof.id));
}
/**
* @notice Computes the EIP712 digest with the given domain parameters.
* Used for testing that different domain parameters fail.
*
* @param _proof Proof struct to hash.
* @param _name Contract name to use in the EIP712 domain.
* @param _version Contract version to use in the EIP712 domain.
* @param _chainid Chain ID to use in the EIP712 domain.
* @param _verifyingContract Address to use in the EIP712 domain.
* @param _verifyingContract Address to use in the EIP712 domain.
* @param _verifyingContract Address to use in the EIP712 domain.
*
* @return EIP-712 compatible digest.
*/
function getDigestWithEIP712Domain(
AdminFaucetAuthModule.Proof memory _proof,
bytes memory _name,
bytes memory _version,
uint256 _chainid,
address _verifyingContract
) public pure returns (bytes32) {
bytes32 domainSeparator = keccak256(
abi.encode(
EIP712_DOMAIN_TYPEHASH,
keccak256(_name),
keccak256(_version),
_chainid,
_verifyingContract
)
);
return ECDSAUpgradeable.toTypedDataHash(domainSeparator, getProofStructHash(_proof));
}
}