Android与C＃之间的加密兼容 [英] Encryption compatible between Android and C#

问题描述

我已经发现了很多示例，如何在C＃中加密，还有一些用于Android，但是我特别寻找一种方法来处理来自Android的加密（使用AES，TripleDES等），以及最终在C＃中被解密。我在Android中发现了一个用于编码AES 的示例，编码/解码AES ，但我不知道这些是否兼容（C＃需要一个IV，在Android示例）。另外，关于通过HTTP（Base64？）传输的加密字符串编码的好方法的建议将是有帮助的。谢谢。

解决方案

从 http://oogifu.blogspot.com/2009/01/aes-in-java-and-c.html 。 p>

这是我的Java类：

  package com.neocodenetworks.smsfwd; 
 
 import java.security。*; 
 import javax.crypto。*; 
 import javax.crypto.spec。*; 
 import android.util.Log; 
 
 public class Crypto {
 public static final String TAG =smsfwd; 
 
私有静态密码aesCipher; 
 private static SecretKey secretKey; 
 private static IvParameterSpec ivParameterSpec; 
 
 private static String CIPHER_TRANSFORMATION =AES / CBC / PKCS5Padding; 
 private static String CIPHER_ALGORITHM =AES; 
 //替换一个16字节的密钥，在Java和C＃之间共享
 private static byte [] rawSecretKey = {0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00，
 0x00，0x00，0x00，0x00，0x00，0x00，0x00，0x00}; 
 
 private static String MESSAGEDIGEST_ALGORITHM =MD5; 
 
 public Crypto（String passphrase）{
 byte [] passwordKey = encodeDigest（passphrase）; 
 
 try {
 aesCipher = Cipher.getInstance（CIPHER_TRANSFORMATION）; 
} catch（NoSuchAlgorithmException e）{
 Log.e（TAG，No such algorithm+ CIPHER_ALGORITHM，e）; 
} catch（NoSuchPaddingException e）{
 Log.e（TAG，No such padding PKCS5，e）; 
} 
 
 secretKey = new SecretKeySpec（passwordKey，CIPHER_ALGORITHM）; 
 ivParameterSpec = new IvParameterSpec（rawSecretKey）; 
} 
 
 public String encryptAsBase64（byte [] clearData）{
 byte [] encryptedData = encrypt（clearData）; 
 return net.iharder.base64.Base64.encodeBytes（encryptedData）; 
} 
 
 public byte [] encrypt（byte [] clearData）{
 try {
 aesCipher.init（Cipher.ENCRYPT_MODE，secretKey，ivParameterSpec）; 
} catch（InvalidKeyException e）{
 Log.e（TAG，无效键，e）; 
返回null; 
} catch（InvalidAlgorithmParameterException e）{
 Log.e（TAG，Invalid algorithm+ CIPHER_ALGORITHM，e）; 
返回null; 
} 
 
 byte [] encryptedData; 
 try {
 encryptedData = aesCipher.doFinal（clearData）; 
} catch（IllegalBlockSizeException e）{
 Log.e（TAG，非法块大小，e）; 
返回null; 
} catch（BadPaddingException e）{
 Log.e（TAG，Bad padding，e）; 
返回null; 
} 
 return encryptedData; 
} 
 
 private byte [] encodeDigest（String text）{
 MessageDigest digest; 
 try {
 digest = MessageDigest.getInstance（MESSAGEDIGEST_ALGORITHM）; 
 return digest.digest（text.getBytes（））; 
} catch（NoSuchAlgorithmException e）{
 Log.e（TAG，No such algorithm+ MESSAGEDIGEST_ALGORITHM，e）; 
} 
 
返回null; 
} 
} 
  

我使用了 http://iharder.sourceforge.net/current/java/base64/ 。

这是我的C＃类：

  using System; 
使用System.Text; 
使用System.Security.Cryptography; 
 
命名空间smsfwdClient 
 {
 public class Crypto 
 {
 private ICryptoTransform rijndaelDecryptor; 
 //替换一个16字节的密钥，在Java和C＃之间共享
 private static byte [] rawSecretKey = {0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00，
 0x00，0x00，0x00，0x00，0x00，0x00，0x00，0x00}; 
 
 public Crypto（string passphrase）
 {
 byte [] passwordKey = encodeDigest（passphrase）; 
 RijndaelManaged rijndael = new RijndaelManaged（）; 
 rijndaelDecryptor = rijndael.CreateDecryptor（passwordKey，rawSecretKey）; 
} 
 
 public string Decrypt（byte [] encryptedData）
 {
 byte [] newClearData = rijndaelDecryptor.TransformFinalBlock（encryptedData，0，encryptedData.Length）; 
 return Encoding.ASCII.GetString（newClearData）; 
} 
 
 public string DecryptFromBase64（string encryptedBase64）
 {
 return Decrypt（Convert.FromBase64String（encryptedBase64））; 
} 
 
 private byte [] encodeDigest（string text）
 {
 MD5CryptoServiceProvider x = new System.Security.Cryptography.MD5CryptoServiceProvider（）; 
 byte [] data = Encoding.ASCII.GetBytes（text）; 
 return x.ComputeHash（data）; 
} 
} 
} 
  

我真的希望这有助于某人其他！

I've found plenty of examples how to do encryption in C#, and a couple for Android, but I'm particularly looking for a way to handle encrypting (using something like AES, TripleDES, etc.) from Android, and eventually wind up being decrypted in C#. I found an example for encoding AES in Android and encoding/decoding AES in C# but am not sure if these are compatible (C# requires an IV, nothing is specified for this in the Android example). Also, a recommendation on a good way of encoding the encrypted string for transmission over HTTP (Base64?) would be helpful. Thanks.

解决方案

Got some help from http://oogifu.blogspot.com/2009/01/aes-in-java-and-c.html.

Here is my Java class:

package com.neocodenetworks.smsfwd;

import java.security.*;
import javax.crypto.*;
import javax.crypto.spec.*;
import android.util.Log;

public class Crypto {
    public static final String TAG = "smsfwd";

    private static Cipher aesCipher;
    private static SecretKey secretKey;
    private static IvParameterSpec ivParameterSpec;

    private static String CIPHER_TRANSFORMATION = "AES/CBC/PKCS5Padding";
    private static String CIPHER_ALGORITHM = "AES";
    // Replace me with a 16-byte key, share between Java and C#
    private static byte[] rawSecretKey = {0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
                                          0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00};

    private static String MESSAGEDIGEST_ALGORITHM = "MD5";

    public Crypto(String passphrase) {
        byte[] passwordKey = encodeDigest(passphrase);

        try {
            aesCipher = Cipher.getInstance(CIPHER_TRANSFORMATION);
        } catch (NoSuchAlgorithmException e) {
            Log.e(TAG, "No such algorithm " + CIPHER_ALGORITHM, e);
        } catch (NoSuchPaddingException e) {
            Log.e(TAG, "No such padding PKCS5", e);
        }

        secretKey = new SecretKeySpec(passwordKey, CIPHER_ALGORITHM);
        ivParameterSpec = new IvParameterSpec(rawSecretKey);
    }

    public String encryptAsBase64(byte[] clearData) {
        byte[] encryptedData = encrypt(clearData);
        return net.iharder.base64.Base64.encodeBytes(encryptedData);
    }

    public byte[] encrypt(byte[] clearData) {
        try {
            aesCipher.init(Cipher.ENCRYPT_MODE, secretKey, ivParameterSpec);
        } catch (InvalidKeyException e) {
            Log.e(TAG, "Invalid key", e);
            return null;
        } catch (InvalidAlgorithmParameterException e) {
            Log.e(TAG, "Invalid algorithm " + CIPHER_ALGORITHM, e);
            return null;
        }

        byte[] encryptedData;
        try {
            encryptedData = aesCipher.doFinal(clearData);
        } catch (IllegalBlockSizeException e) {
            Log.e(TAG, "Illegal block size", e);
            return null;
        } catch (BadPaddingException e) {
            Log.e(TAG, "Bad padding", e);
            return null;
        }
        return encryptedData;
    }

    private byte[] encodeDigest(String text) {
        MessageDigest digest;
        try {
            digest = MessageDigest.getInstance(MESSAGEDIGEST_ALGORITHM);
            return digest.digest(text.getBytes());
        } catch (NoSuchAlgorithmException e) {
            Log.e(TAG, "No such algorithm " + MESSAGEDIGEST_ALGORITHM, e);
        }

        return null;
    }
}

I used http://iharder.sourceforge.net/current/java/base64/ for the base64 encoding.

Here's my C# class:

using System;
using System.Text;
using System.Security.Cryptography;

namespace smsfwdClient
{
    public class Crypto
    {
        private ICryptoTransform rijndaelDecryptor;
        // Replace me with a 16-byte key, share between Java and C#
        private static byte[] rawSecretKey = {0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
                                              0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00};

        public Crypto(string passphrase)
        {
            byte[] passwordKey = encodeDigest(passphrase);
            RijndaelManaged rijndael = new RijndaelManaged();
            rijndaelDecryptor = rijndael.CreateDecryptor(passwordKey, rawSecretKey);
        }

        public string Decrypt(byte[] encryptedData)
        {
            byte[] newClearData = rijndaelDecryptor.TransformFinalBlock(encryptedData, 0, encryptedData.Length);
            return Encoding.ASCII.GetString(newClearData);
        }

        public string DecryptFromBase64(string encryptedBase64)
        {
            return Decrypt(Convert.FromBase64String(encryptedBase64));
        }

        private byte[] encodeDigest(string text)
        {
            MD5CryptoServiceProvider x = new System.Security.Cryptography.MD5CryptoServiceProvider();
            byte[] data = Encoding.ASCII.GetBytes(text);
            return x.ComputeHash(data);
        }
    }
}

I really hope this helps someone else!

这篇关于Android与C＃之间的加密兼容的文章就介绍到这了，希望我们推荐的答案对大家有所帮助，也希望大家多多支持IT屋！