Nodejs javascript implementation of PBEWithMD5AndTripleDES/CBC/PKCS5Padding

Question

In order to write an simple nodejs app talking to an server written in java I have to implement the following functionality for nodejs.

public class Crypto {         


        

Answer 1

My final solution 5 years ago was:

var forge = require('node-forge');
var crypto = require('crypto');
var base64Coder = require('./utils/tac-base64coder');
var ByteBuffer = forge.util.ByteBuffer;

var DES_EDE_KEY_LEN = 24;
var DES_BLOCK_SIZE = 8;
var SALT_BYTES = [0x45, 0xC4, 0x31, 0x72, 0x8A, 0x62, 0xB3, 0x9A];
var KEY_BUFFER_LENGTH = 24;
var IV_BUFFER_LENGTH = 8;

module.exports = {

  /**
   * Generates the derived key. The 16 bytes of the first digest and the 1st 8 bytes of the 2nd digest
   * form the triple DES key, and the last 8 bytes of the 2nd digest form the IV.
   *
   * @method _deriveCipherKey
   * @param {String}      key       The key phrase
   * @param {Int8Array}   salt      The salt
   * @param {Number}      iCount    The iteration count
   * @returns {Buffer}
   * @private
   */
  _deriveCipherKey: function _deriveCipherKey (key, salt, iCount) {
    var md;
    var passwdBytes = new Buffer(key);
    var i;
    var toBeHashed;
    var result = new Buffer(DES_EDE_KEY_LEN + DES_BLOCK_SIZE);
    result.fill(0);

    // if the 2 salt halves are the same, invert one of them
    for (i = 0; i < 4; i++) {
      if (salt[i] !== salt[i + 4]) {
        break;
      }
    }

    if (i === 4) { // same, invert 1st half
      for (i = 0; i < 2; i++) {
        var tmp = salt[i];
        salt[i] = salt[3 - i];
        salt[3 - 1] = tmp;
      }
    }

    for (i = 0; i < 2; i++) {
      toBeHashed = new Buffer(salt.length / 2);
      toBeHashed.fill(0);

      salt.copy(toBeHashed, 0, i * (salt.length / 2));

      for (var j = 0; j < iCount; j++) {
        md = crypto.createHash('md5');
        md.update(toBeHashed);
        md.update(passwdBytes);
        toBeHashed = md.digest();
      }
      toBeHashed.copy(result, i * 16);
    }

    return result;
  },

  /**
   * Encrypts the given string with the given key
   *
   * @method encrypt
   * @param {String}      encryptionKey   The encryption key
   * @param {String}      toEncrypt       The string to encrypt
   * @returns {String}
   */
  encrypt: function encrypt (encryptionKey, toEncrypt) {
    var encodedStr = forge.util.encodeUtf8(toEncrypt);
    var salt = new Buffer(SALT_BYTES);
    var key = new Buffer(KEY_BUFFER_LENGTH);
    var iv = new Buffer(IV_BUFFER_LENGTH);
    var key2 = new ByteBuffer();
    var iv2 = new ByteBuffer();
    var derivedKey = this._deriveCipherKey(encryptionKey, salt, 12);
    var cipher;
    var i = 0;

    derivedKey.copy(key, 0, 0, 24);
    derivedKey.copy(iv, 0, 24);

    for (; i < KEY_BUFFER_LENGTH; i++) {
      key2.putByte(key[i]);
    }

    for (i = 0; i < IV_BUFFER_LENGTH; i++) {
      iv2.putByte(iv[i]);
    }

    cipher = forge.des.createEncryptionCipher(key2);
    cipher.start(iv2);
    cipher.update(forge.util.createBuffer(encodedStr));
    cipher.finish();

    return base64Coder.encode(cipher.output.getBytes().toString());
  },

  /**
   * Decrypts the given base64 string with the given key
   *
   * @method decrypt
   * @param {String}      encryptionKey     The decryption key
   * @param {String}      toDecrypt         The encrypted base64 string
   * @returns {String}
   */
  decrypt: function decrypt (encryptionKey, toDecrypt) {
    var decr = forge.util.decode64(toDecrypt);
    var salt = new Buffer(SALT_BYTES);
    var key = new Buffer(KEY_BUFFER_LENGTH);
    var iv = new Buffer(IV_BUFFER_LENGTH);
    var derivedKey = this._deriveCipherKey(encryptionKey, salt, 12);
    var key2 = new forge.util.ByteBuffer();
    var iv2 = new forge.util.ByteBuffer();
    var i = 0;
    var cipher;

    derivedKey.copy(key, 0, 0, 24);
    derivedKey.copy(iv, 0, 24);

    for (; i < KEY_BUFFER_LENGTH; i++) {
      key2.putByte(key[i]);
    }

    for (i = 0; i < IV_BUFFER_LENGTH; i++) {
      iv2.putByte(iv[i]);
    }

    cipher = forge.des.createDecryptionCipher(key2);

    cipher.start(iv2);
    cipher.update(forge.util.createBuffer(decr));
    cipher.finish();

    return cipher.output.getBytes().toString('utf8');
  }
};