从Dot net到Java的AES 256解密

从.NET到Java的AES-256解密过程涉及到几个关键步骤，包括确保两端使用相同的加密算法、密钥、初始化向量（IV）以及填充方式。以下是一个详细的步骤指南和示例代码，帮助你完成从.NET加密的数据在Java中的解密。

1. 确保两端使用相同的参数

加密算法：AES-256
密钥长度：256位
初始化向量（IV）：确保两端使用相同的IV
填充方式：例如PKCS7Padding

2. .NET端加密示例

假设你在.NET端已经有了加密的数据，以下是一个加密示例：

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

public class AesEncryption
{
    private static readonly byte[] Salt = new byte[] { 0x26, 0xdc, 0xff, 0x00, 0xad, 0xed, 0x7a, 0xee, 0xc5, 0xfe, 0x07, 0xaf, 0x4d, 0x08, 0x22, 0x3c };

    public static byte[] Encrypt(string plainText, byte[] key)
    {
        using (Aes aesAlg = Aes.Create())
        {
            aesAlg.Key = key;
            aesAlg.IV = GenerateIV();
            aesAlg.Padding = PaddingMode.PKCS7;

            ICryptoTransform encryptor = aesAlg.CreateEncryptor(aesAlg.Key, aesAlg.IV);

            using (MemoryStream msEncrypt = new MemoryStream())
            {
                using (CryptoStream csEncrypt = new CryptoStream(msEncrypt, encryptor, CryptoStreamMode.Write))
                {
                    using (StreamWriter swEncrypt = new StreamWriter(csEncrypt))
                    {
                        swEncrypt.Write(plainText);
                    }
                    return msEncrypt.ToArray();
                }
            }
        }
    }

    private static byte[] GenerateIV()
    {
        using (RNGCryptoServiceProvider rng = new RNGCryptoServiceProvider())
        {
            byte[] iv = new byte[16];
            rng.GetBytes(iv);
            return iv;
        }
    }
}

3. Java端解密示例

以下是一个Java端的解密示例，用于解密.NET端加密的数据：

import javax.crypto.Cipher;
import javax.crypto.spec.IvParameterSpec;
import javax.crypto.spec.SecretKeySpec;
import java.util.Base64;

public class AesDecryption {
    private static final byte[] SALT = new byte[]{(byte) 0x26, (byte) 0xdc, (byte) 0xff, (byte) 0x00, (byte) 0xad, (byte) 0xed, (byte) 0x7a, (byte) 0xee, (byte) 0xc5, (byte) 0xfe, (byte) 0x07, (byte) 0xaf, (byte) 0x4d, (byte) 0x08, (byte) 0x22, (byte) 0x3c};

    public static String decrypt(String encryptedText, byte[] key) throws Exception {
        byte[] encryptedBytes = Base64.getDecoder().decode(encryptedText);
        byte[] iv = new byte[16];
        System.arraycopy(encryptedBytes, 0, iv, 0, 16);

        SecretKeySpec secretKeySpec = new SecretKeySpec(key, "AES");
        IvParameterSpec ivParameterSpec = new IvParameterSpec(iv);

        Cipher cipher = Cipher.getInstance("AES/CBC/PKCS5Padding");
        cipher.init(Cipher.DECRYPT_MODE, secretKeySpec, ivParameterSpec);

        byte[] decryptedBytes = cipher.doFinal(encryptedBytes, 16, encryptedBytes.length - 16);
        return new String(decryptedBytes);
    }

    public static void main(String[] args) {
        try {
            String encryptedText = "..."; // 从.NET端获取的加密文本
            byte[] key = "...".getBytes("UTF-8"); // 确保与.NET端使用的密钥相同

            String decryptedText = decrypt(encryptedText, key);
            System.out.println("Decrypted Text: " + decryptedText);
        } catch (Exception e) {
            e.printStackTrace();
        }
    }
}