使用Rijndael算法在Android上使用256位密钥加密/解密 [英] Encryption / Decryption using Rijndael with key 256bit on Android

问题描述

我开发一个Android应用程序，它消耗WS。
对于在Android应用程序和WebService之间的信息交换，您必须使用256位密钥的算法加密/解密的Rijndael。

I am developing an Android application that consumes a WS. For exchange of information between the android application and WebService, you must use the algorithm encryption / decryption Rijndael with 256 bit key.

也就是说，从WS返回的所有信息，都将被加密，所以我使用的算法进行解密。

That is, all the information returned from the WS, will be encrypted, so I decrypts them using the algorithm.

同样，所有我发送到WS的信息进行加密。因此，我将使用的加密算法。

Likewise, all the information I send to WS should be encrypted. Therefore, I will use the encryption algorithm.

我还没有发现的Rijndael准备在Android平台上使用。但我在C＃中相同的算法。

I have not found the Rijndael ready to be used in the android platform. But I have the same algorithm in C #.

public class KeydKey
{
    public KeydKey()
    {

    }


    #region Metodos de Criptografia
    #region key
    public string key(string vstrTextToBeEncrypted, string vstrEncryptionKey)
    {
        byte[] bytValue;
        byte[] bytKey;
        byte[] bytEncoded;
        byte[] bytIV = { 121, 241, 10, 1, 132, 74, 11, 39, 255, 91, 45, 78, 14, 211, 22, 62 };
        int intLength;
        int intRemaining;
        MemoryStream objMemoryStream = new MemoryStream();
        CryptoStream objCryptoStream;
        RijndaelManaged objRijndaelManaged;

        //O valor deve estar dentro da tabela ASCII (i.e., no DBCS chars)  
        bytValue = Encoding.UTF32.GetBytes(vstrTextToBeEncrypted.ToCharArray());
        intLength = vstrEncryptionKey.Length;

        /* 
           ******A chave cifrada será de 256 bits long (32 bytes)                             
           ****** Se for maior que 32 bytes então será truncado.                               
           ****** Se for menor que 32 bytes será alocado.                                        
           ****** Usando upper-case Xs
         */
        if (intLength >= 32)
        {
            vstrEncryptionKey = vstrEncryptionKey.Substring(0, 32);
        }
        else
        {
            intLength = vstrEncryptionKey.Length;
            intRemaining = 32 - intLength;
            string tmp = "";
            vstrEncryptionKey = vstrEncryptionKey + tmp.PadRight(intRemaining, 'X');
        }

        bytKey = Encoding.ASCII.GetBytes(vstrEncryptionKey.ToCharArray());
        objRijndaelManaged = new RijndaelManaged();

        /*  ****** Cria o valor a ser crifrado e depois escreve                                  
            ****** Convertido em uma disposição do byte 
         */
        try
        {
            objCryptoStream = new CryptoStream(objMemoryStream, objRijndaelManaged.CreateEncryptor(bytKey, bytIV), CryptoStreamMode.Write);
            objCryptoStream.Write(bytValue, 0, bytValue.Length);

            objCryptoStream.FlushFinalBlock();

            bytEncoded = objMemoryStream.ToArray();
            objMemoryStream.Close();
            objCryptoStream.Close();
            return Convert.ToBase64String(bytEncoded);
        }
        catch (Exception ex)
        {
            return null;
        }
    }
    #endregion

    #region dkey
    public string dkey(string vstrstringToBeDecrypted, string vstrDecryptionKey)
    {
        byte[] bytDataToBeDecrypted;
        byte[] bytTemp = new byte[0];
        byte[] bytIV = { 121, 241, 10, 1, 132, 74, 11, 39, 255, 91, 45, 78, 14, 211, 22, 62 };
        MemoryStream objMemoryStream = new MemoryStream();
        CryptoStream objCryptoStream;
        RijndaelManaged objRijndaelManaged;
        byte[] bytDecryptionKey;
        int intLength;
        int intRemaining;
        string strReturnstring = string.Empty;

        //Convert base64 cifrada para byte array
        bytDataToBeDecrypted = Convert.FromBase64String(vstrstringToBeDecrypted);
        intLength = vstrDecryptionKey.Length;

        /* 
           ******A chave cifrada será de 256 bits long (32 bytes)                             
           ****** Se for maior que 32 bytes então será truncado.                               
           ****** Se for menor que 32 bytes será alocado.                                        
           ****** Usando upper-case Xs
         */
        if (intLength >= 32)
        {
            vstrDecryptionKey = vstrDecryptionKey.Substring(0, 32);
        }
        else
        {
            intLength = vstrDecryptionKey.Length;
            intRemaining = 32 - intLength;
            string tmp = "";
            vstrDecryptionKey = vstrDecryptionKey + tmp.PadRight(intRemaining, 'X');
        }

        bytDecryptionKey = Encoding.ASCII.GetBytes(vstrDecryptionKey.ToCharArray());
        objRijndaelManaged = new RijndaelManaged();

        Array.Resize(ref bytTemp, bytDataToBeDecrypted.Length);

        objMemoryStream = new MemoryStream(bytDataToBeDecrypted);


        try
        {

            objCryptoStream = new CryptoStream(objMemoryStream, objRijndaelManaged.CreateDecryptor(bytDecryptionKey, bytIV), CryptoStreamMode.Read);
            objCryptoStream.Read(bytTemp, 0, bytTemp.Length);
            //objCryptoStream.FlushFinalBlock();
            objMemoryStream.Close();
            objCryptoStream.Close();
            return Encoding.UTF32.GetString(bytTemp).Replace("\0", "");
        }
        catch (Exception ex)
        {
            return null;
        }
    }

    #endregion

    #endregion


}

有人告诉我在哪里可以下载Android的算法？或者帮我翻译，我有Java的算法？

Someone tell me where I can get the algorithm for android? Or help me translate the algorithm that I have Java?

感谢您！

推荐答案

Cipher.getInstance（AES / CBC / PKCS5Padding）应该做的伎俩。你将不得不匹配（字符）-encodings，你可以使用 SecretKeySpec（字节[32]）以创建一个256位的AES密钥。

Cipher.getInstance("AES/CBC/PKCS5Padding") should do the trick. You will have to match (character)-encodings and you may use SecretKeySpec(byte[32]) to create a 256 bit AES key.

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