method to create hash and salt

create_hash_and_salt.js

import crypto from 'crypto'
import semver from 'semver'

const processVersion = '0.12.0'; 

const pbkdf2DigestSupport = semver.gte(process.version, processVersion);

const pbkdf2 = (pwd, salt, options, callback) => {
  const { iterations, keylen, digestAlgorithm } = options;
  if (pbkdf2DigestSupport) {
    crypto.pbkdf2(pwd, salt, iterations, keylen, digestAlgorithm, callback);
  } else {
    crypto.pbkdf2(pwd, salt, iterations, keylen, callback);
  }
}

const createHashAndSalt = (pwd, options) => {
  return new Promise((resolve, reject) => {  
    crypto.randomBytes(options.saltlen, (randomBytesErr, buf) => {
      if (randomBytesErr) {
        return reject(randomBytesErr)
      }
      const salt = buf.toString(options.encoding);
      pbkdf2(pwd, salt, options, (pbkdf2Err, hashRaw) => {
        if (pbkdf2Err) {
          return reject(pbkdf2Err)   
        }
        return resolve({
          hash: new Buffer(hashRaw, 'binary').toString(options.encoding),
          salt
        });
      });
    });
  });
};

const options = {
  'saltlen': 32,
  'iterations': 25000,
  'keylen': 512,
  'encoding': 'hex',
  'digestAlgorithm': 'sha256'
}

const wantedPassword = 'supersecret';
createHashAndSalt(wantedPassword, options).then(resp => {
  console.log(resp)
});