weijiekoh/eip712-signing-demo

Demonstrates MetaMask's eip_signTypedData_v3 feature

eip712-signing-demo's Issues

Does work with 4.10 but not in 4.13 (chrome)

Console shows RPC error.

Can be reproduced by installing both extensions and switching between them, each time reloading the site.

How to check sign in solidity, if I have only one struct?

https://medium.com/metamask/eip712-is-coming-what-to-expect-and-how-to-use-it-bb92fd1a7a26 There is no explanation of what exactly happens in the contract. I created data for my situation. In Javascript, the signature is created correctly and checked correctly, there are no problems with it. But in the contract, I always get FALSE. Can anyone explain me, what wrong in contract?
My JS data structure for tests:
`const domain = [{
name: "name",
type: "string"
}, {
name: "version",
type: "string"
}, {
name: "chainId",
type: "uint256"
}];

const userscore = [{
	name: "user",
	type: "address"
}, {
	name: "score",
	type: "uint256"
}, {
	name: "id",
	type: "uint256"
}, {
	name: "expire",
	type: "uint256"
}];

// Data
const domainData = {
	name: "Simple Dapp",
	version: "1",
	chainId: 1,
	verifyingContract: "0xCcCCccccCCCCcCCCCCCcCcCccCcCCCcCcccccccC"
};

var message = {
	user: "0xe0428E45F41ae8a46284A9B64AB27e0B15A2eAF7",
	score: 20,
	id: 1,
	expire: 20
};

let msgParams = JSON.stringify({
	types: {
		EIP712Domain: domain,
		UserScore: userscore
	},
	domain: domainData,
	primaryType: "UserScore",
	message: message
})`

And my contract code, with correct address, r, s, v and another things.
`pragma experimental ABIEncoderV2;
pragma solidity ^0.5.0;

contract Verifier {
uint256 constant chainId = 1;

string private constant EIP712_DOMAIN  = "EIP712Domain(string name,string version,uint256 chainId)";
string private constant USERSCORE_TYPE = "UserScore(address user,uint256 score,uint256 id,uint256 time)";

bytes32 private constant EIP712_DOMAIN_TYPEHASH = keccak256(abi.encodePacked(EIP712_DOMAIN));
bytes32 private constant USERSCORE_TYPEHASH = keccak256(abi.encodePacked(USERSCORE_TYPE));

bytes32 private constant DOMAIN_SEPARATOR = keccak256(abi.encode(
    EIP712_DOMAIN_TYPEHASH,
    keccak256("Simple Dapp"),
    keccak256("1"),
    chainId
));

struct UserScore {
    address user;
    uint256 score;
    uint256 id;
    uint256 time;
}

function hashUserScore(UserScore memory userscore) private pure returns (bytes32){
    return keccak256(abi.encodePacked(
        "\x19\x01",
        DOMAIN_SEPARATOR,
        keccak256(abi.encode(
            USERSCORE_TYPEHASH,
            userscore.user,
            userscore.score,
            userscore.id,
            userscore.time
        ))
    ));
}

function verify() public pure returns (bool) {
    UserScore memory userscore = UserScore({
        user: 0xe0428E45F41ae8a46284A9B64AB27e0B15A2eAF7,
        score: 20,
        id: 1,
        time: 20
    });
        
    bytes32 sigR = 0x1443eafac538e7a767cbc1308e34ef088734b7e59dcd25baedace361a4356be1;
    bytes32 sigS = 0x2fd582b765b7cf85c3137c06dbfbfb58f02a2a891cc8c78bb4f781888d5a2a7e;
    uint8 sigV = 28;
    address signer = 0xe0428E45F41ae8a46284A9B64AB27e0B15A2eAF7;

    return signer == ecrecover(hashUserScore(userscore), sigV, sigR, sigS);
}

}`

Update README to 4.14.0 or above

The sample is working with 4.14 at least, probably also newer versions, would be nice to have this mentioned in the README.

Verify signatures in MetaMask

The example is very useful.
It would be very useful to also have a function which verifies the validity of the signature in Javascript.

How to send this sign?

Update README to version 4.14 or above

The sample is working with 4.14 at least, probably also newer versions, would be nice to have this mentioned in the README, currently it recommends 4.10 still.