ao-lib/crypto.js

import crypto from 'crypto' // Does not work on client because this is a Node library, but works for below server-only functions
// These libraries are old but they work and can be included on both server and client
import shajs from 'sha.js'
import hmac from 'hash.js/lib/hash/hmac.js'
import sha256 from 'hash.js/lib/hash/sha/256.js' // Only works for shorter hashes, not in createHash used for hashing meme files

export function createHash(payload) {
  return shajs('sha256').update(payload).digest('hex')
}

export function hmacHex(data, signingKey) {
  return hmac(sha256, signingKey).update(data).digest('hex')
}

export function derivePublicKey(p) {
  return crypto.createPublicKey(p).export({
    type: 'spki',
    format: 'pem',
  })
}

export function encryptToPublic(pub, info) {
  return crypto.publicEncrypt(pub, new Buffer(info)).toString('hex')
}

export function decryptFromPrivate(priv, hiddenInfo) {
  return crypto
    .privateDecrypt(priv, Buffer.from(hiddenInfo, 'hex'))
    .toString('latin1')
}