src/crypto.ts
import * as Account from 'eth-lib/lib/account'
import * as Hash from 'eth-lib/lib/hash'
import * as web3Utils from 'web3-utils'
/**
* Like web3.eth.accounts.hashMessage without the envelope.
*
* @param {*} data
* A message to hash - if it is hex it'll be UTF8 decoded.
*
* @returns {*}
* The hashed message (using keccak256)
*/
export const hashMsgRaw = (data: string | number[]): string => {
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 {*} messageHash
* Hash of a message, as returned by `web3.utils.soliditySha3` or similar.
* @param {*} privateKey
* Privkey to sign with.
*
* @returns {{messageHash: string, r: string, s: string, v: string}}
*/
export const ethSignHash = (messageHash: string, privateKey: string) => {
// 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
}
}
export /**
*
* Operates `ecrecover` over the provided signature
*
* @param {string} messageHash This should be an Ethereum HexString
* @param {string[]} [v, r, s] Components for the secp256k1 signature
* @returns {{verified: bool, address: EthAddress}}
*/
const ethVerifySig = (messageHash: string, [v, r, s]: string[]) => {
const address = Account.recover(
messageHash,
Account.encodeSignature([v, r, s])
)
return {
verified: true,
address
}
}