Support eth_signTypedData

[schmidsi]

Similar to #129 , there is another JSON RPC command that needs to be intercepted: eth_signTypedData as described in: EIP-712

[schmidsi]

I think this screenshot actually makes the point ;)

[schmidsi]

The 0x team implements this logic in their subprovider: https://github.com/0xProject/0x-monorepo/blob/master/packages/subproviders/src/subproviders/private_key_wallet.ts#L99

They intercept the call and serialize the typed data so it can be sent through eth_signMessage finally.

[schmidsi]

Here is an example object:

const typedData = {
    types: {
        EIP712Domain: [
            { name: 'name', type: 'string' },
            { name: 'version', type: 'string' },
            { name: 'chainId', type: 'uint256' },
            { name: 'verifyingContract', type: 'address' },
        ],
        Person: [
            { name: 'name', type: 'string' },
            { name: 'wallet', type: 'address' }
        ],
        Mail: [
            { name: 'from', type: 'Person' },
            { name: 'to', type: 'Person' },
            { name: 'contents', type: 'string' }
        ],
    },
    primaryType: 'Mail',
    domain: {
        name: 'Ether Mail',
        version: '1',
        chainId: 1,
        verifyingContract: '0xCcCCccccCCCCcCCCCCCcCcCccCcCCCcCcccccccC',
    },
    message: {
        from: {
            name: 'Cow',
            wallet: '0xCD2a3d9F938E13CD947Ec05AbC7FE734Df8DD826',
        },
        to: {
            name: 'Bob',
            wallet: '0xbBbBBBBbbBBBbbbBbbBbbbbBBbBbbbbBbBbbBBbB',
        },
        contents: 'Hello, Bob!',
    },
};

From: https://github.com/ethereum/EIPs/blob/master/assets/eip-712/Example.js#L5

[schmidsi]

A simple test of the functionality can be done with the following bash command:

curl -X POST --url http://127.0.0.1:1248 --data '{"jsonrpc":"2.0","method":"eth_signTypedData","params":["0xCD2a3d9F938E13CD947Ec05AbC7FE734Df8DD826", {"types":{"EIP712Domain":[{"name":"name","type":"string"},{"name":"version","type":"string"},{"name":"chainId","type":"uint256"},{"name":"verifyingContract","type":"address"}],"Person":[{"name":"name","type":"string"},{"name":"wallet","type":"address"}],"Mail":[{"name":"from","type":"Person"},{"name":"to","type":"Person"},{"name":"contents","type":"string"}]},"primaryType":"Mail","domain":{"name":"Ether Mail","version":"1","chainId":1,"verifyingContract":"0xCcCCccccCCCCcCCCCCCcCcCccCcCCCcCcccccccC"},"message":{"from":{"name":"Cow","wallet":"0xCD2a3d9F938E13CD947Ec05AbC7FE734Df8DD826"},"to":{"name":"Bob","wallet":"0xbBbBBBBbbBBBbbbBbbBbbbbBBbBbbbbBbBbbBBbB"},"contents":"Hello, Bob!"}}],"id":1}'

[schmidsi]

This is how it looks like in https://github.com/MetaMask/metamask-extension/:

From here: https://app.kovan.radarrelay.com/ZRX/WETH

The rendered JSON is not interactable.

[schmidsi]

Real-world example of EIP-712: https://dicether.com/

[schmidsi]

It seems like eth_signTypedData is not available in Trezor nor Ledger at the moment.

It also doesn't work in MetaMask:

• Error when signing messages using a Ledger-connected wallet MetaMask/metamask-extension#5319
• eth_signTypedData on Trezor account fails without callback MetaMask/metamask-extension#5052

There is a WIP pull-request in the Trezor-firmware repo:
trezor/trezor-firmware#148

And a stale issue in the Ledger repo:
LedgerHQ/ledgerjs#86

So I think, we can close this issue for now since #183 add support for hot wallets and just wait for the native hardware wallet support.

[mohamedmansour]

@schmidsi the latest trezor update has EIP712 which implemented eth_signTypedData, but frame doesn't recognize it, are there ways we can help test/debug?