src/crypto.js
const Account = require('eth-lib/lib/account');
const Hash = require("eth-lib/lib/hash");
const web3Utils = require('web3-utils');
/**
* Like web3.eth.accounts.hashMessage without the envelope.
*
* @param {string} data
* A message to hash - if it is hex it'll be UTF8 decoded.
*
* @returns {string}
* The hashed message (using keccak256)
*/
export const hashMsgRaw = data => {
const msg = web3Utils.isHexStrict(data) ? web3Utils.hexToBytes(data) : data;
const msgBuffer = Buffer.from(msg);
return Hash.keccak256s(msgBuffer);
}
/**
* Sign a message such that it can be verified with `ecrecover`.
* Similar to `web3.eth.accounts.sign` except that we sign the hash directly.
*
* @param {string} messageHash
* Hash of a message, as returned by `web3.utils.soliditySha3` or similar.
* @param {string} privateKey
* Privkey to sign with.
*
* @returns {{messageHash: string, r: string, s: string, v: string}}
*/
export const ethSignHash = (messageHash, privateKey) => {
// near identical to web3-eth-accounts (web3 v1)
// the main difference is we don't envelop the data.
const signature = Account.sign(messageHash, privateKey);
const vrs = Account.decodeSignature(signature);
return {
messageHash,
v: vrs[0],
r: vrs[1],
s: vrs[2],
signature
}
}