Dat crypto

dat-libsodium-seal.js

const sodium = require('sodium-universal')

function keyPair(seed) {
  var publicKey = new Buffer(sodium.crypto_sign_PUBLICKEYBYTES)
  var secretKey = new Buffer(sodium.crypto_sign_SECRETKEYBYTES)

  sodium.crypto_sign_keypair(publicKey, secretKey)

  return {
    publicKey: publicKey,
    secretKey: secretKey
  }
}

function seal(msg, publicKey) {
    var cipher = new Buffer(msg.length + sodium.crypto_box_SEALBYTES)
    sodium.crypto_box_seal(cipher, msg, publicKey)
    return cipher
}

function unseal(cipher, publicKey, secretKey) {
    if (cipher.length < sodium.crypto_box_SEALBYTES) return null
    var msg = new Buffer(cipher.length - sodium.crypto_box_SEALBYTES)
    if (!sodium.crypto_box_seal_open(msg, cipher, publicKey, secretKey)) return null
    return msg
}

function verifyKeyPair(publicKey, secretKey) {
    const msg = Buffer.from('test', 'utf-8')
    const cipher = seal(msg, publicKey)
    const decrypted = unseal(cipher, publicKey, secretKey)
    // 'decrypted' is always null
    console.log('verify:', msg.toString('utf-8'), decrypted ? decrypted.toString('utf-8') : decrypted)
}

const keypair = keyPair()
console.info(keypair)
verifyKeyPair(keypair.publicKey, keypair.secretKey)