2

我现在面临一个问题，需要你们帮助。

我使用 c# 进行一些加密。然后需要使用node.js来decry-pt它。但我只是发现我不能根据我的 c# 加密算法正确地做到这一点。如果你们有任何解决方案，请帮助我。

这是我的 c# 加密代码：

public static string Encrypt(string text, String password, string salt, string hashAlgorithm, int passwordIterations, string initialVector, int keySize)
{
    if (string.IsNullOrEmpty(text))
        return "";

    var initialVectorBytes = Encoding.ASCII.GetBytes(initialVector);
    var saltValueBytes = Encoding.ASCII.GetBytes(salt);
    var plainTextBytes = Encoding.UTF8.GetBytes(text);
    var derivedPassword = new PasswordDeriveBytes(password, saltValueBytes, hashAlgorithm, passwordIterations);
    var keyBytes = derivedPassword.GetBytes(keySize / 8);
    var symmetricKey = new RijndaelManaged();
    symmetricKey.Mode = CipherMode.CBC;
    byte[] cipherTextBytes = null;
    using (var encryptor = symmetricKey.CreateEncryptor(keyBytes, initialVectorBytes))
    {
        using (var memStream = new MemoryStream())
        {
            using (var cryptoStream = new CryptoStream(memStream, encryptor, CryptoStreamMode.Write))
            {
                cryptoStream.Write(plainTextBytes, 0, plainTextBytes.Length);
                cryptoStream.FlushFinalBlock();
                cipherTextBytes = memStream.ToArray();
                memStream.Close();
                cryptoStream.Close();
            }
        }
    }
    symmetricKey.Clear();
    return Convert.ToBase64String(cipherTextBytes);
}
public static string Decrypt(string text, String password, string salt, string hashAlgorithm, int passwordIterations, string initialVector, int keySize)
{
    if (string.IsNullOrEmpty(text))
        return "";

    var initialVectorBytes = Encoding.ASCII.GetBytes(initialVector);
    var saltValueBytes = Encoding.ASCII.GetBytes(salt);
    var cipherTextBytes = Convert.FromBase64String(text);
    var derivedPassword = new PasswordDeriveBytes(password, saltValueBytes, hashAlgorithm, passwordIterations);
    var keyBytes = derivedPassword.GetBytes(keySize / 8);
    var symmetricKey = new RijndaelManaged();
    symmetricKey.Mode = CipherMode.CBC;
    var plainTextBytes = new byte[cipherTextBytes.Length];
    var byteCount = 0;
    using (var decryptor = symmetricKey.CreateDecryptor(keyBytes, initialVectorBytes))
    {
        using (var memStream = new MemoryStream(cipherTextBytes))
        {
            using (var cryptoStream = new CryptoStream(memStream, decryptor, CryptoStreamMode.Read))
            {

                byteCount = cryptoStream.Read(plainTextBytes, 0, plainTextBytes.Length);
                memStream.Close();
                cryptoStream.Close();
            }
        }
    }
    symmetricKey.Clear();
    return Encoding.UTF8.GetString(plainTextBytes, 0, byteCount);    
}

如果有人可以为我提供与 nodejs 相同的功能，那将非常有帮助。无论如何，感谢您阅读这篇文章。

4

3 回答 3

2

首先，我们将PasswordDeriveBytes使用 Node.js 执行该功能。这是crypto.pbkdf2：

// assumes HMAC-SHA1
crypto.pbkdf2(password, salt, iterations, keySize / 8, function(err, key) {
    if(err) /* handle error */
    // ...
});

接下来，用于crypto.createDecipheriv创建解密器：

// find algorithm from the available ciphers; see crypto.getCiphers()
var decipher = crypto.createDecipheriv(/* algorithm */, key, initialVector);

然后使用decipher.updateanddecipher.final向它提供数据。他们会将部分解密数据返回给您。

于 2013-04-29T03:47:40.810 回答
1

问题是，PasswordDeriveBytes 没有实现 pbkdf2，而是 pbkdf1 的修改版本（PKCS #5 v2.1）。有关更多信息，请参阅此 算法背后的密码衍生 字节。

注意：PasswordDeriveBytes 构造函数的默认值是迭代次数 = 100 和 hashAlgorithm = "sha1"

这是我在 javascript/typescript 中实现此算法的方法：

export function deriveBytesFromPassword(password: string, salt: Buffer, iterations: number, hashAlgorithm: string, keyLength: number) {
    if (keyLength < 1) throw new Error("keyLength must be greater than 1")
    if (iterations < 2) throw new Error("iterations must be greater than 2")

    const passwordWithSalt = Buffer.concat([Buffer.from(password, "utf-8"), salt])
    const hashMissingLastIteration = hashKeyNTimes(passwordWithSalt, iterations - 1, hashAlgorithm)
    let result = hashKeyNTimes(hashMissingLastIteration, 1, hashAlgorithm)
    result = extendResultIfNeeded(result, keyLength, hashMissingLastIteration, hashAlgorithm)

    return result.slice(0, keyLength)
}

function hashKeyNTimes(key: Buffer, times: number, hashAlgorithm: string): Buffer {
    let result = key
    for (let i = 0; i < times; i++) {
        result = crypto.createHash(hashAlgorithm).update(result).digest()
    }
    return result
}

function extendResultIfNeeded(result: Buffer, keyLength: number, hashMissingLastIteration: Buffer, hashAlgorithm: string): Buffer {
    let counter = 1
    while (result.length < keyLength) {
        result = Buffer.concat([result, calculateSpecialMicrosoftHash(hashMissingLastIteration, counter, hashAlgorithm)])
        counter++
    }
    return result
}

function calculateSpecialMicrosoftHash(hashMissingLastIteration: Buffer, counter: number, hashAlgorithm: string): Buffer {
    // Here comes the magic: Convert an integer that increases from call to call to a string
    // and convert that string to utf-8 bytes. These bytes are than used to slightly modify a given base-hash.
    // The modified hash is than piped through the hash algorithm.
    // Note: The PasswordDeriveBytes algorithm converts each character to utf-16 and then drops the second byte.
    const prefixCalculatedByCounter = Buffer.from(counter.toString(), "utf-8")
    const inputForAdditionalHashIteration = Buffer.concat([prefixCalculatedByCounter, hashMissingLastIteration])
    return crypto.createHash(hashAlgorithm).update(inputForAdditionalHashIteration).digest()
}
于 2021-10-27T06:46:48.790 回答
0

在完全相同的情况下，我能够使用上面@icktoofay 提供的代码获得成功的“C# 加密 => 节点解密”解决方案，但将PasswordDeriveBytes替换为Rfc2898DeriveBytes

我的代码大致是：

C＃

private byte[] saltBytes = ASCIIEncoding.ASCII.GetBytes(salt);

public string Encrypt<T>(string value, string password) where T: SymmetricAlgorithm, new() {
  byte[] valueBytes = UTF8Encoding.UTF8.GetBytes(value);

  byte[] encrypted = null;
  using (T cipher = new T()) {
    var db = new Rfc2898DeriveBytes(password, saltBytes);
    db.IterationCount = iterationsConst;
    var key = db.GetBytes(keySizeConst / 8);

    cipher.Mode = CipherMode.CBC;

    using (ICryptoTransform encryptor = cipher.CreateEncryptor(key, vectorBytes)) {
      using (MemoryStream ms = new MemoryStream()) {
        using (CryptoStream cs = new CryptoStream(ms, encryptor, CryptoStreamMode.Write)) {
          cs.Write(valueBytes, 0, valueBytes.Length);
          cs.FlushFinalBlock();
          encrypted = ms.ToArray();
        }
      }
    }
    cipher.Clear();
  }
  return Convert.ToBase64String(encrypted);
}

JavaScript：

var crypto = require('crypto');
var base64 = require('base64-js');
var algorithm = 'AES-256-CBC';

[...]

var saltBuffer = new Buffer(salt);
var passwordBuffer = new Buffer(password);

[...]

var encodedBuffer = new Buffer(base64.toByteArray(encryptedStringBase64Encoded));

crypto.pbkdf2(passwordBuffer, saltBuffer, iterations, keySize / 8, function(err, key) {
  var decipher = crypto.createDecipheriv(algorithm, key, iv);
  var dec = Buffer.concat([decipher.update(encodedBuffer), decipher.final()]);
  return dec;
});

实际上是我在互联网上找到的几个例子的组合。

因为在某些特定情况下，Buffer 的 Base64 实现存在问题（编码字符串开头的“+”号），所以我使用了https://github.com/beatgammit/base64-js中的 base64-js ，它似乎工作正常。

于 2016-01-20T14:13:46.387 回答