Node backend helper file for https://github.com/amitaymolko/react-native-rsa-native

encryption.js

'use strict';

var NodeRSA = require('node-rsa');
var CryptoJS = require('crypto-js');
const crypto = require('crypto')

let generateKeyPair = (password) => {
    let key = new NodeRSA();
    key.generateKeyPair()
    let publicKey = Buffer.from(key.exportKey('public')).toString('base64')
    let privateKey = Buffer.from(key.exportKey('private')).toString('base64')
    if(password) {
        privateKey = encryptUsingPassword(privateKey, password)
    }
    return {publicKey, privateKey}
} 

let decryptUsingKeys = (privateKeyString, encryptedMessage) => {  
    let privateKey = Buffer.from(privateKeyString, 'base64').toString()
    let key = {
        key: privateKey,
        padding: crypto.constants.RSA_PKCS1_PADDING
    }
    let message = crypto.privateDecrypt(key, Buffer.from(encryptedMessage, 'base64')).toString()
    return message
}

let encryptUsingKeys = (publicKeyString, message) => {
    let publicKey = Buffer.from(publicKeyString, 'base64').toString()
    let key = {
      key: publicKey,
      padding: crypto.constants.RSA_PKCS1_PADDING
    }
    let encryptedMessage = crypto.publicEncrypt(key, Buffer.from(message)).toString('base64')
    return encryptedMessage
}

let encryptUsingPassword = (decrypted, password) => {
  return CryptoJS.AES.encrypt(decrypted, password).toString()
}

let decryptUsingPassword = (encrypted, password) => {
  return CryptoJS.AES.decrypt(encrypted, password).toString(CryptoJS.enc.Utf8)
}

module.exports = {
  keys: {
    generate: generateKeyPair,
    decrypt: decryptUsingKeys,
    encrypt: encryptUsingKeys
  },
  password: {
    decrypt: decryptUsingPassword,
    encrypt: encryptUsingPassword
  }
}