js-peer-id/src/index.js

/*
 * Id is an object representation of a peer Id. a peer Id is a multihash
 */

var multihashing = require('multihashing')
var base58 = require('bs58')
var keypair = require('keypair')
var forge = require('node-forge')

exports = module.exports = Id

exports.Buffer = Buffer

function Id (id, privKey, pubKey) {
  var self = this

  if (!(self instanceof Id)) {
    throw new Error('Id must be called with new')
  }

  self.privKey = privKey
  self.pubKey = pubKey
  self.id = id // multihash - sha256 - buffer

  // pretty print

  self.toPrint = function () {
    return {
      id: self.toHexString(),
      privKey: privKey.toString('hex'),
      pubKey: pubKey.toString('hex')
    }
  }

  // encode/decode functions

  self.toHexString = function () {
    return self.id.toString('hex')
  }

  self.toBytes = function () {
    return self.id
  }

  self.toB58String = function () {
    return base58.encode(self.id)
  }
}

function fix (str) {
  return str.replace(/\r/g, '') + '\n'
}

// generation

exports.create = function () {
  var pair = keypair()

  var mhId = multihashing(pair.public, 'sha2-256')

  return new Id(mhId, pair.private, pair.public)
}

exports.createFromHexString = function (str) {
  return new Id(new Buffer(str), 'hex')
}

exports.createFromBytes = function (buf) {
  return new Id(buf)
}

exports.createFromB58String = function (str) {
  return new Id(new Buffer(base58.decode(str)))
}

exports.createFromPubKey = function (pubKey) {
  var mhId = multihashing(pubKey, 'sha2-256')
  return new Id(mhId, null, pubKey)
}

exports.createFromPrivKey = function (privKey) {
  var privateKey = forge.pki.privateKeyFromPem(privKey)
  var publicKey = {
    n: privateKey.n,
    e: privateKey.e
  }
  var pubKey = fix(forge.pki.publicKeyToRSAPublicKeyPem(publicKey, 72))
  var mhId = multihashing(pubKey, 'sha2-256')
  return new Id(mhId, privKey, pubKey)
}