viem/accounts/utils/sign.ts

TypeScript Interface for Ethereum

import { secp256k1 } from '@noble/curves/secp256k1'

import type { ErrorType } from '../../errors/utils.js'
import type { Hex, Signature } from '../../types/misc.js'
import { type ToHexErrorType, toHex } from '../../utils/encoding/toHex.js'

export type SignParameters = {
  hash: Hex
  privateKey: Hex
}

export type SignReturnType = Signature

export type SignErrorType = ToHexErrorType | ErrorType

/**
 * @description Signs a hash with a given private key.
 *
 * @param hash The hash to sign.
 * @param privateKey The private key to sign with.
 *
 * @returns The signature.
 */
export async function sign({
  hash,
  privateKey,
}: SignParameters): Promise<SignReturnType> {
  const { r, s, recovery } = secp256k1.sign(hash.slice(2), privateKey.slice(2))
  return {
    r: toHex(r),
    s: toHex(s),
    v: recovery ? 28n : 27n,
  }
}