C#和javascript兼容的AES加解密

人气:778 发布:2022-10-16 标签: javascript c# cryptography aes cryptojs

问题描述

我正在尝试用C#和Javascript编写两个类,在交换数据时,我可以在整个项目中使用这两个类来使用AES加密或解密数据。

使用AES I在加密结果中嵌入SALT(32字节)和IV(16字节),这在测试时分别适用于这两个类。将盐和IV添加到混合物中并不会引出很多参考资料来使其在两个平台之间工作。

对于C#,我使用的是标准的System.Security.Crypthography。AES

 private static readonly int iterations = 1000;

    public static string Encrypt(string input, string password)
    {
        byte[] encrypted;
        byte[] IV;
        byte[] Salt = GetSalt();
        byte[] Key = CreateKey(password, Salt);

        using (Aes aesAlg = Aes.Create())
        {
            aesAlg.Key = Key;
            aesAlg.Padding = PaddingMode.PKCS7;
            aesAlg.Mode = CipherMode.CBC;

            aesAlg.GenerateIV();
            IV = aesAlg.IV;

            var encryptor = aesAlg.CreateEncryptor(aesAlg.Key, aesAlg.IV);

            using (var msEncrypt = new MemoryStream())
            {
                using (var csEncrypt = new CryptoStream(msEncrypt, encryptor, CryptoStreamMode.Write))
                {
                    using (var swEncrypt = new StreamWriter(csEncrypt))
                    {
                        swEncrypt.Write(input);
                    }
                    encrypted = msEncrypt.ToArray();
                }
            }
        }

        byte[] combinedIvSaltCt = new byte[Salt.Length + IV.Length + encrypted.Length];
        Array.Copy(Salt, 0, combinedIvSaltCt, 0, Salt.Length);
        Array.Copy(IV, 0, combinedIvSaltCt, Salt.Length, IV.Length);
        Array.Copy(encrypted, 0, combinedIvSaltCt, Salt.Length + IV.Length, encrypted.Length);

        return Convert.ToBase64String(combinedIvSaltCt.ToArray());
    }

    public static string Decrypt(string input, string password)
    {
        byte[] inputAsByteArray;
        string plaintext = null;
        try
        {
            inputAsByteArray = Convert.FromBase64String(input);

            byte[] Salt = new byte[32];
            byte[] IV = new byte[16];
            byte[] Encoded = new byte[inputAsByteArray.Length - Salt.Length - IV.Length];

            Array.Copy(inputAsByteArray, 0, Salt, 0, Salt.Length);
            Array.Copy(inputAsByteArray, Salt.Length, IV, 0, IV.Length);
            Array.Copy(inputAsByteArray, Salt.Length + IV.Length, Encoded, 0, Encoded.Length);

            byte[] Key = CreateKey(password, Salt);

            using (Aes aesAlg = Aes.Create())
            {
                aesAlg.Key = Key;
                aesAlg.IV = IV;
                aesAlg.Mode = CipherMode.CBC;
                aesAlg.Padding = PaddingMode.PKCS7;

                ICryptoTransform decryptor = aesAlg.CreateDecryptor(aesAlg.Key, aesAlg.IV);

                using (var msDecrypt = new MemoryStream(Encoded))
                {
                    using (var csDecrypt = new CryptoStream(msDecrypt, decryptor, CryptoStreamMode.Read))
                    {
                        using (var srDecrypt = new StreamReader(csDecrypt))
                        {
                            plaintext = srDecrypt.ReadToEnd();
                        }
                    }
                }
            }

            return plaintext;
        }
        catch (Exception e)
        {
            return null;
        }
    }

    public static byte[] CreateKey(string password, byte[] salt)
    {
        using (var rfc2898DeriveBytes = new Rfc2898DeriveBytes(password, salt, iterations))
            return rfc2898DeriveBytes.GetBytes(32);
    }

    private static byte[] GetSalt()
    {
        var salt = new byte[32];
        using (var random = new RNGCryptoServiceProvider())
        {
            random.GetNonZeroBytes(salt);
        }

        return salt;
    }

对于我正在使用的Javascript解决方案,基于此引用使用CryptoJShttp://www.adonespitogo.com/articles/encrypting-data-with-cryptojs-aes/

    var keySize = 256;
var ivSize = 128;
var saltSize = 256;
var iterations = 1000;

var message = "Hello World";
var password = "Secret Password";


function encrypt (msg, pass) {
  var salt = CryptoJS.lib.WordArray.random(saltSize/8);

  var key = CryptoJS.PBKDF2(pass, salt, {
      keySize: keySize/32,
      iterations: iterations
    });

  var iv = CryptoJS.lib.WordArray.random(ivSize/8);

  var encrypted = CryptoJS.AES.encrypt(msg, key, { 
    iv: iv, 
    padding: CryptoJS.pad.Pkcs7,
    mode: CryptoJS.mode.CBC

  });

  // salt, iv will be hex 32 in length
  // append them to the ciphertext for use  in decryption
  var transitmessage = salt + iv + encrypted;
  return transitmessage.toString();
}

function decrypt (transitmessage, pass) {
  var salt = CryptoJS.enc.Hex.parse(transitmessage.substr(0, 64));
  var iv = CryptoJS.enc.Hex.parse(transitmessage.substr(64, 32));
  var encrypted = transitmessage.substring(96);

  var key = CryptoJS.PBKDF2(pass, salt, {
      keySize: keySize/32,
      iterations: iterations
    });

  var decrypted = CryptoJS.AES.decrypt(encrypted, key, { 
    iv: iv, 
    padding: CryptoJS.pad.Pkcs7,
    mode: CryptoJS.mode.CBC

  })
  return decrypted.toString(CryptoJS.enc.Utf8);
}

使用的密码:Secret Password

C#结果: r7Oi1vMXZ5mYJay8i+slbJZEiT3CxV/1zOYntbZIsS5RuasABJKQQQVvAe50U1deIIqyQiwzQWYelMJ48WWpMQ==

Javascript结果:72ff8e7b653efbe3101d2c4ca7d7fe1af06652b907a90281aafa5ae09b45c9af091571b08d3d39cbad129939488319b2pprMQFFEJZR5JlrDsMqT8w==

结果应为Hello World

这两种解决方案在它们自己的环境中都工作得很好,但是C#或Javascript散列不能交换,它们也不会解密。我的猜测是字符编码与此有关,因此Base64大小差别如此之大。有没有人有办法让这一切一起运作?谢谢!

推荐答案

错误在Javascript代码中,第一部分是祸不单行,最后是base64的加密结果。

下面的Javascript代码使AES结果可以与上面提供的C#解决方案互换。我在确保所有结果都能在祸不单行中正确编码和解码时遇到了一些困难,因此添加了一些新函数。

var keySize = 256;
var ivSize = 128;
var saltSize = 256;
var iterations = 1000;

var message = "Does this work?";
var password = "Secret Password";


function encrypt (msg, pass) {
  var salt = CryptoJS.lib.WordArray.random(saltSize/8);

  var key = CryptoJS.PBKDF2(pass, salt, {
      keySize: keySize/32,
      iterations: iterations
    });

  var iv = CryptoJS.lib.WordArray.random(ivSize/8);

  var encrypted = CryptoJS.AES.encrypt(msg, key, { 
    iv: iv, 
    padding: CryptoJS.pad.Pkcs7,
    mode: CryptoJS.mode.CBC

  });

    var encryptedHex = base64ToHex(encrypted.toString());
    var base64result = hexToBase64(salt + iv + encryptedHex);


  return base64result;
}

function decrypt (transitmessage, pass) {

  var hexResult = base64ToHex(transitmessage)

  var salt = CryptoJS.enc.Hex.parse(hexResult.substr(0, 64));
  var iv = CryptoJS.enc.Hex.parse(hexResult.substr(64, 32));
  var encrypted = hexToBase64(hexResult.substring(96));

  var key = CryptoJS.PBKDF2(pass, salt, {
      keySize: keySize/32,
      iterations: iterations
    });

  var decrypted = CryptoJS.AES.decrypt(encrypted, key, { 
    iv: iv, 
    padding: CryptoJS.pad.Pkcs7,
    mode: CryptoJS.mode.CBC

  })

  return decrypted.toString(CryptoJS.enc.Utf8); 
}

function hexToBase64(str) {
  return btoa(String.fromCharCode.apply(null,
    str.replace(/|
/g, "").replace(/([da-fA-F]{2}) ?/g, "0x$1 ").replace(/ +$/, "").split(" "))
  );
}

function base64ToHex(str) {
  for (var i = 0, bin = atob(str.replace(/[ 
]+$/, "")), hex = []; i < bin.length; ++i) {
    var tmp = bin.charCodeAt(i).toString(16);
    if (tmp.length === 1) tmp = "0" + tmp;
    hex[hex.length] = tmp;
  }
  return hex.join("");
}

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