Question

我正在使用代码对Base进行编码并对c＃中的数据进行加密，然后我将文件发送到我尝试解密的Android应用程序。

问题是，我得到一个“Base64编码输入字符串的长度不是4的倍数”。解密时出错：

（Android的Java代码）：

    try
    {
          Boolean inEvent = false;

          // read encrypted file to string
          BufferedInputStream fin = new BufferedInputStream(new FileInputStream(filename));
          ByteArrayOutputStream bout = new ByteArrayOutputStream();
          byte buffer[] = new byte[8192];
          int read = fin.read(buffer);
          while(read != -1) {
              bout.write(buffer, 0, read);
              read = fin.read(buffer);
          }
          fin.close();
          String encryptedText = bout.toByteArray().toString();
          String unencryptedText = "";

          // decrypt string
          try
          {
              unencryptedText = Decrypt(encryptedText, sKey); <-- error occurs here
          }
          catch ( Exception e)
          {
              alert(e.getMessage());
              return sched;
          }

解密方法：

protected String Decrypt(String text, String key) throws Exception
{
    Cipher cipher = Cipher.getInstance("AES/CBC/PKCS7Padding");
    byte[] keyBytes= new byte[16];
    byte[] b= key.getBytes("UTF-8");
    int len= b.length;
    if (len > keyBytes.length) len = keyBytes.length;
    System.arraycopy(b, 0, keyBytes, 0, len);
    SecretKeySpec keySpec = new SecretKeySpec(keyBytes, "AES");
    IvParameterSpec ivSpec = new IvParameterSpec(keyBytes);
    cipher.init(Cipher.DECRYPT_MODE,keySpec,ivSpec);

    byte [] results = cipher.doFinal(Base64Coder.decode(text));
    return new String(results,"UTF-8");
}

最后，这是我正在加密的c＃代码：

（c＃代码）：

  string Encrypt(string textToEncrypt, string key)
  {
    RijndaelManaged rijndaelCipher = new RijndaelManaged();
    rijndaelCipher.Mode = CipherMode.CBC;
    rijndaelCipher.Padding = PaddingMode.PKCS7;

    rijndaelCipher.KeySize = 0x80;
    rijndaelCipher.BlockSize = 0x80;
    byte[] pwdBytes = Encoding.UTF8.GetBytes(key);
    byte[] keyBytes = new byte[0x10];
    int len = pwdBytes.Length;
    if (len > keyBytes.Length)
    {
      len = keyBytes.Length;
    }
    Array.Copy(pwdBytes, keyBytes, len);
    rijndaelCipher.Key = keyBytes;
    rijndaelCipher.IV = keyBytes;
    ICryptoTransform transform = rijndaelCipher.CreateEncryptor();
    byte[] plainText = Encoding.UTF8.GetBytes(textToEncrypt);
    return Convert.ToBase64String(transform.TransformFinalBlock(plainText, 0,   plainText.Length));
  }

不确定是什么问题。密钥的长度是否必须是某个特定的字节数？

Answer 1

评论已经确定了问题，如果您在此处调试了关键项目，您会立即看到它：您认为正在阅读的基本64字符串。

您从bout中的文件中收集字节。但是你试图将它转换为字符串表示并没有像你想象的那样做任何事情。它将类似于“[B @ 2352544e]”，只是来自数组的Java内部默认toString()。相反，请尝试new String(bout.toByteArray(), Charset.forName("US-ASCII"))。

Base64编码数据的问题（加密和c＃，在java中解密）

1 个答案: