解密由.NET的RijndaelManaged使用Java加密的字节

Question

我正在尝试解密使用RijndaelManaged of .NET/C#加密的东西,使用Java进行解密.

C#程序不是我的; 我无法将其更改为更具互操作性.但我知道它是如何加密的:

byte[] bytes = new UnicodeEncoding().GetBytes(password); // edit: built-in is 8chars
FileStream fileStream = new FileStream(outputFile, FileMode.Create);
RijndaelManaged rijndaelManaged = new RijndaelManaged();
CryptoStream cryptoStream = new CryptoStream((Stream) fileStream,
    rijndaelManaged.CreateEncryptor(bytes, bytes), CryptoStreamMode.Write);

我不知道如何在Java端解密这个.我发现最接近有用的是这篇博客文章,但它对实际细节很清楚,我无法实现解密器.

编辑:我是个白痴,现在有了它的工作.

UnicodeEncoding是UTF-16LE,而我使用的是UTF-8.在插入密码时切换到正确的编码已修复程序.

我还需要得到BouncyCastle并且做到 Cipher.getInstance("AES/CBC/PKCS7Padding", "BC");

finaledit:这是用Java 解密来自.NET 的默认 RijndaelManaged流的代码,假设它是使用原始密码作为密钥创建的:

Security.addProvider(new org.bouncycastle.jce.provider.BouncyCastleProvider());
String password = "kallisti"; // only 8, 12, or 16 chars will work as a key
byte[] key = password.getBytes(Charset.forName("UTF-16LE"));
Cipher cipher = Cipher.getInstance("AES/CBC/PKCS7Padding", "BC");
cipher.init(Cipher.DECRYPT_MODE, new SecretKeySpec(key, "AES"),
    new IvParameterSpec(key));
return cipher; // then use CipherInputStream(InputStream, Cipher)

请记住:如果您控制C#端,请不要使用未获得的密码作为密钥!

Answer 1

可以使用标准 AES 解密。Rijndel 只是 AES 的超集，它对特定选项更加宽松。有关更多详细信息，请参阅Java 中的 Rijndael 支持。

从链接问题中给出的答案来看：

byte[] sessionKey = null; //Where you get this from is beyond the scope of this post
byte[] iv = null ; //Ditto
byte[] plaintext = null; //Whatever you want to encrypt/decrypt
Cipher cipher = Cipher.getInstance("AES/CBC/PKCS5Padding");
//You can use ENCRYPT_MODE or DECRYPT_MODE
cipher.calling init(Cipher.DECRYPT_MODE, new SecretKeySpec(sessionKey, "AES"), new IvParameterSpec(iv));
byte[] ciphertext = cipher.doFinal(plaintext);