C＃.NET AES与JavaScript的互操作性

Question

我一直在尝试以互操作方式通过AES和C＃加密和解密字符串。我的客户端应用程序是一个节点服务器，与供应商的API通信在DOT Net中。

供应商使用这些方法来加密和解密字符串：

public static string Encrypt(string data, string key)
{
  string IV = key.Substring(0, 16);
  byte[] iv = Encoding.UTF8.GetBytes(IV);
  byte[] array;
  using(Aes aes = Aes.Create())
  {
    aes.Key = Encoding.UTF8.GetBytes(key);
    aes.IV = iv;
    ICryptoTransform encryptor = aes.CreateEncryptor(aes.Key, aes.IV);
    using(MemoryStream memoryStream = new MemoryStream())
    {
      using(CryptoStream cryptoStream = new CryptoStream((Stream)memoryStream, encryptor, CryptoStreamMode.Write))
      {
        using(StreamWriter streamWriter = new StreamWriter((Stream)cryptoStream))
        {
          streamWriter.Write(data);
        }
        array = memoryStream.ToArray();
      }
    }
  }
  return Convert.ToBase64String(array);
}



public static string Decrypt(string data, string key)
{
  string IV = key.Substring(0, 16);
  byte[] iv = Encoding.UTF8.GetBytes(IV);
  byte[] buffer = Convert.FromBase64String(data);
  using(Aes aes = Aes.Create())
  {
    aes.Key = Encoding.UTF8.GetBytes(key);
    aes.IV = iv;
    ICryptoTransform decryptor = aes.CreateDecryptor(aes.Key, aes.IV);
    using(MemoryStream memoryStream = new MemoryStream(buffer))
    {
      using(CryptoStream cryptoStream = new CryptoStream((Stream)memoryStream, decryptor, CryptoStreamMode.Read))
      {
        using(StreamReader streamReader = new StreamReader((Stream)cryptoStream))
        {
          return streamReader.ReadToEnd();
        }
      }
    }
  }
}

我尝试了crypto-js解密字符串，但我无法使其可行：

const encryptedText = CryptoJS.enc.Base64.parse(base64Value)
const encrypted2 = encryptedText.toString(CryptoJS.enc.Base64);
const decrypt2 = CryptoJS.AES.decrypt(encrypted2, key, {
 mode: CryptoJS.mode.ECB,
 padding: CryptoJS.pad.Pkcs7
});

console.log(decrypt2.toString(CryptoJS.enc.Utf8)) // (also tried various other encodings, Utf16, Utf16LE and others)

Answer 1

以下Node.js代码应与您的.NET代码正确使用。

我们使用算法AES-256-CBC来匹配C＃示例中使用的模式。

const crypto = require("crypto");
const Algorithm = "aes-256-cbc";

function encrypt(plainText, key, iv, outputEncoding = "base64") {
    const cipher = crypto.createCipheriv(Algorithm, key, iv);
    const output = Buffer.concat([cipher.update(plainText), cipher.final()]).toString(outputEncoding);
    return output.replace('+', '-').replace('/', '_').replace('=', '');
}

function decrypt(cipherText, key, iv, outputEncoding = "utf8") {
    cipherText = Buffer.from(cipherText, "base64");
    const cipher = crypto.createDecipheriv(Algorithm, key, iv);
    return Buffer.concat([cipher.update(cipherText), cipher.final()]).toString(outputEncoding);
}

const KEY = 'KFmnMAPzP!g@6Dy5HD?JSgYC9obE&m@m';
const IV = KEY.slice(0,16);

// Taking the output from our C# sample...
const encrypted = 'SORoNS48u0KniiANU3Y9Mw==';
console.log("Encrypted (base64):", encrypted);
const decrypted = decrypt(encrypted, KEY, IV)
console.log("Decrypted:", decrypted);

等效c＃代码如下：

using System;
using System.Text;
using System.Security.Cryptography;
using System.IO;
                    
public class Program
{
    public static void Main()
    {
        var str = Encrypt("test", "KFmnMAPzP!g@6Dy5HD?JSgYC9obE&m@m");
        Console.WriteLine("Encrypted: " + str);
        Console.WriteLine("Decrypted: " + Decrypt(str, "KFmnMAPzP!g@6Dy5HD?JSgYC9obE&m@m"));
    }
    
    public static string Encrypt(string data, string key)
    {
      string IV = key.Substring(0, 16);
      byte[] iv = Encoding.UTF8.GetBytes(IV);
      byte[] array;
      using(Aes aes = Aes.Create())
      {
        aes.Key = Encoding.UTF8.GetBytes(key);
        aes.IV = iv;
        ICryptoTransform encryptor = aes.CreateEncryptor(aes.Key, aes.IV);
        using(MemoryStream memoryStream = new MemoryStream())
        {
          using(CryptoStream cryptoStream = new CryptoStream((Stream)memoryStream, encryptor, CryptoStreamMode.Write))
          {
            using(StreamWriter streamWriter = new StreamWriter((Stream)cryptoStream))
            {
              streamWriter.Write(data);
            }
            array = memoryStream.ToArray();
          }
        }
      }
      return Convert.ToBase64String(array);
    }



    public static string Decrypt(string data, string key)
    {
      string IV = key.Substring(0, 16);
      byte[] iv = Encoding.UTF8.GetBytes(IV);
      byte[] buffer = Convert.FromBase64String(data);
      using(Aes aes = Aes.Create())
      {
        aes.Key = Encoding.UTF8.GetBytes(key);
        aes.IV = iv;
        ICryptoTransform decryptor = aes.CreateDecryptor(aes.Key, aes.IV);
        using(MemoryStream memoryStream = new MemoryStream(buffer))
        {
          using(CryptoStream cryptoStream = new CryptoStream((Stream)memoryStream, decryptor, CryptoStreamMode.Read))
          {
            using(StreamReader streamReader = new StreamReader((Stream)cryptoStream))
            {
              return streamReader.ReadToEnd();
            }
          }
        }
      }
    }
}

C＃代码的输出是：

 Encrypted: SORoNS48u0KniiANU3Y9Mw==
 Decrypted: test

Node.js代码，然后解密此（使用相同的密钥和IV）：

 Encrypted (base64): SORoNS48u0KniiANU3Y9Mw=
 Decrypted: test

Answer 2

由于您使用的是nodejs，因此使用nodejs的加密模块而不是加密j（请参阅其他答案）。当然，Cryptojs也是可能的。然后必须考虑以下内容：

在JavaScript代码中，必须使用CBC模式，并且必须以WordArray cryptojs.aes.decrypt（）（）将键和IV传递给键和IV。 。可以传递base64编码的密文，隐式将其转换为cipherparams对象。

默认情况下，CryptoJS应用CBC和PKCS＃7填充，因此不需要明确指定这些填充物（当然可以）。

以下示例中的密文是使用C＃代码生成的，可以使用以下cryptojs代码进行解密：

const ciphertext = 'yKiV9TBw3eNt2QvK1kdXaw=='; 
const keyStr = "01234567890123456789012345678901"; // 32 bytes -> AES-256
const key = CryptoJS.enc.Utf8.parse(keyStr);
const IV = CryptoJS.enc.Utf8.parse(keyStr.substr(0, 16));
const decrypted = CryptoJS.AES.decrypt(ciphertext, key, {iv: IV}); // apply default: CBC and PKCS#7 padding

console.log(decrypted.toString(CryptoJS.enc.Utf8)); // Hello world!

<script src="https://cdnjs.cloudflare.com/ajax/libs/crypto-js/4.1.1/crypto-js.min.js"></script>

关于安全：
将键（或其中的一部分）与IV一起使用是不安全的。相反，应为每个加密生成一个随机静脉输液。这不是秘密，并与密文一起通过，通常是串联的。
此外，从文本中生成键也会降低安全性（即使使用正确的尺寸，值范围也会降低）。如果涉及文本/密码，则更安全的是使用可靠的密钥推导函数，例如PBKDF2。