C# 到 Java TripleDES，不同的结果

Question

我正在尝试将此 C# 加密算法转换为 Java；但是，我一直在检索略有不同的加密结果（尚未尝试解密）。指出我无法更改 C# 代码可能也很重要。

但是，当我在 C# 中对字符串“test”调用加密函数时，它将返回 nmj8MjjO52y928Syqf0J+g== 但是在 Java 中，它将返回 C6xyQjJCqVo=

C#

private static String key = "012345678901234567890123";

public static string encrypt(String stringToEncrypt)
{
    TripleDES des = CreateDES(key);
    ICryptoTransform ct = des.CreateEncryptor();
    byte[] input = Encoding.Unicode.GetBytes(stringToEncrypt);
    byte[] output = ct.TransformFinalBlock(input, 0, input.Length);
    //return output;
    return Convert.ToBase64String(output);
}


public static String decrypt(string encryptedString)
{
    byte[] input = Convert.FromBase64String(encryptedString);
    TripleDES des = CreateDES(key);
    ICryptoTransform ct = des.CreateDecryptor();
    byte[] output = ct.TransformFinalBlock(input, 0, input.Length);
    return Encoding.Unicode.GetString(output);
}


public static TripleDES CreateDES(string key)
{
    MD5 md5 = new MD5CryptoServiceProvider();
    TripleDES des = new TripleDESCryptoServiceProvider();
    des.Key = md5.ComputeHash(Encoding.Unicode.GetBytes(key));
    des.IV = new byte[des.BlockSize / 8];
    return des;
}

我尝试转换为 Java

private static String key = "012345678901234567890123";

public static void main(String[] args) throws Exception {
    String text = "test";
    String codedtext = encrypt(text);
    //String decodedtext = decrypt(codedtext);

    System.out.println(new String(codedtext));
    //System.out.println(decodedtext); 
}

public static String encrypt(String message) throws Exception {
    MessageDigest md = MessageDigest.getInstance("md5");
    byte[] digestOfPassword = md.digest(key.getBytes("unicode"));
    byte[] keyBytes = Arrays.copyOf(digestOfPassword, 24);
    //for (int j = 0, k = 16; j < 8;) {
    //  keyBytes[k++] = keyBytes[j++];
    //}

    SecretKey key = new SecretKeySpec(keyBytes, "DESede");
    IvParameterSpec iv = new IvParameterSpec(new byte[8]);
    Cipher cipher = Cipher.getInstance("DESede/CBC/PKCS5Padding");
    cipher.init(Cipher.ENCRYPT_MODE, key, iv);

    byte[] plainTextBytes = message.getBytes();
    byte[] cipherText = cipher.doFinal(plainTextBytes);

    String output = Base64.encode(cipherText);

    return output;
}

public static String decrypt(String message) throws Exception {
    byte[] messageBytes = Base64.decode(message);

    MessageDigest md = MessageDigest.getInstance("md5");
    byte[] digestOfPassword = md.digest(key.getBytes());
    byte[] keyBytes = Arrays.copyOf(digestOfPassword, 24);
    for (int j = 0, k = 16; j < 8;) {
        keyBytes[k++] = keyBytes[j++];
    }

    SecretKey key = new SecretKeySpec(keyBytes, "DESede");
    IvParameterSpec iv = new IvParameterSpec(new byte[8]);
    Cipher decipher = Cipher.getInstance("DESede/CBC/PKCS5Padding");
    decipher.init(Cipher.DECRYPT_MODE, key, iv);

    byte[] plainText = decipher.doFinal(messageBytes);

    return new String(plainText);
}

有人看到我在监督什么吗？

Answer 1

你错过了两件事。您在 c# 端使用 16 长度的密钥，因为它不像 Java 版本那样填充。默认情况下，如果密钥长度为 16 字节，它将用密钥的前 8 个字节填充。

要在 Java 端进行此匹配，您必须取消注释将填充添加到键的行：

for (int j = 0, k = 16; j < 8;) {
  keyBytes[k++] = keyBytes[j++];
}

SecretKey secretKey = new SecretKeySpec(keyBytes, 0, 24, "DESede");

此外，在 java 方面，有人建议确保对文本使用 UTF-LE。确保将它用于一切。所以这些行：

byte[] digestOfPassword = md.digest(key.getBytes("UTF-16LE"));

byte[] plainTextBytes = clearText.getBytes("UTF-16LE");

一般来说，我会确保设置所有三元组对象的 c# 参数，而不是依赖于默认值。

这里有两个在c#和java中匹配的版本

Java

String key = "012345678901234567890123";
String clearText = "test";

MessageDigest md = MessageDigest.getInstance("md5");
byte[] digestOfPassword = md.digest(key.getBytes("UTF-16LE"));

byte[] keyBytes = Arrays.copyOf(digestOfPassword, 24);
String byteText = Arrays.toString(keyBytes);

for (int j = 0, k = 16; j < 8;) {
  keyBytes[k++] = keyBytes[j++];
}

SecretKey secretKey = new SecretKeySpec(keyBytes, 0, 24, "DESede");

IvParameterSpec iv = new IvParameterSpec(new byte[8]);
Cipher cipher = Cipher.getInstance("DESede/CBC/PKCS5Padding");

cipher.init(Cipher.ENCRYPT_MODE, secretKey, iv);

byte[] plainTextBytes = clearText.getBytes("UTF-16LE");
byte[] cipherText = cipher.doFinal(plainTextBytes);

String output = Base64.encode(cipherText);

c#

string clearText = "test";
string key = "012345678901234567890123";
string encryptedText = "";

MD5 md5 = new MD5CryptoServiceProvider();
TripleDES des = new TripleDESCryptoServiceProvider();
des.KeySize = 128;
des.Mode = CipherMode.CBC;
des.Padding = PaddingMode.PKCS7;

byte[] md5Bytes = md5.ComputeHash(Encoding.Unicode.GetBytes(key));

byte[] ivBytes = new byte[8];


des.Key = md5Bytes;

des.IV = ivBytes;

byte[] clearBytes = Encoding.Unicode.GetBytes(clearText);

ICryptoTransform ct = des.CreateEncryptor();
using (MemoryStream ms = new MemoryStream())
{
    using (CryptoStream cs = new CryptoStream(ms, des.CreateEncryptor(), CryptoStreamMode.Write))
    {
        cs.Write(clearBytes, 0, clearBytes.Length);
        cs.Close();
    }
    encryptedText = Convert.ToBase64String(ms.ToArray());
}

已编辑：两个版本现在都返回测试用例结果“nmj8MjjO52y928Syqf0J+g=="