C#与Java加密解密互通之AES算法

前不久做一个项目接口对接，C#的程序调用Java程序的Api接口，而这个Api接口为了安全性，所有参数必须统一采用AES和RSA加密算法进行加密，返回的结果也是经过Java的AES和RSA加密。本来以为C#和Java常用的AES加密解密都是互通的，没想到完全不是那么一回事。网上也查了不少方案，靠谱的几乎没有，几经摸索，终于找到了AES算法互通的方案。下面直接上代码。

C# AES加密解密程序。

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

namespace AESUtils
{
    public class AESUtils
    {
        /// <summary>AES加密</summary>
        /// <param name="text">明文</param>
        /// <param name="key">密钥,长度为16的字符串</param>
        /// <returns>密文</returns>
        public static string EncodeAES(string text, string key)
        {
            RijndaelManaged rijndaelCipher = new RijndaelManaged();
            rijndaelCipher.Mode = CipherMode.CBC;
            rijndaelCipher.Padding = PaddingMode.PKCS7;
            rijndaelCipher.KeySize = 128;
            rijndaelCipher.BlockSize = 128;
            byte[] pwdBytes = Encoding.UTF8.GetBytes(key);
            byte[] keyBytes = new byte[16];
            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(text);
            byte[] cipherBytes = transform.TransformFinalBlock(plainText, 0, plainText.Length);
            return Convert.ToBase64String(cipherBytes);
        }

        /// <summary>AES解密</summary>
        /// <param name="text">密文</param>
        /// <param name="key">密钥,长度为16的字符串</param>
        /// <returns>明文</returns>
        public static string DecodeAES(string text, string key)
        {
            RijndaelManaged rijndaelCipher = new RijndaelManaged();
            rijndaelCipher.Mode = CipherMode.CBC;
            rijndaelCipher.Padding = PaddingMode.PKCS7;
            rijndaelCipher.KeySize = 128;
            rijndaelCipher.BlockSize = 128;
            byte[] encryptedData = Convert.FromBase64String(text);
            byte[] pwdBytes = Encoding.UTF8.GetBytes(key);
            byte[] keyBytes = new byte[16];
            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.CreateDecryptor();
            byte[] plainText = transform.TransformFinalBlock(encryptedData, 0, encryptedData.Length);
            return Encoding.UTF8.GetString(plainText);
        }
    }
}

Java核心加密解密程序。

import javax.crypto.Cipher;
import javax.crypto.spec.IvParameterSpec;
import javax.crypto.spec.SecretKeySpec;

public class AESUtils {
/**
 * AES算法加密明文
 * @param data 明文
 * @param key 密钥，长度16
 * @param iv 偏移量，长度16
 * @return 密文
 */
  public static String encryptAES(String data,String key,String iv) throws Exception {
        try {
            Cipher cipher = Cipher.getInstance("AES/CBC/PKCS5Padding"); //or NoPadding
            int blockSize = cipher.getBlockSize();
            byte[] dataBytes = data.getBytes();
            int plaintextLength = dataBytes.length;
             
            if (plaintextLength % blockSize != 0) {
                plaintextLength = plaintextLength + (blockSize - (plaintextLength % blockSize));
            }
 
            byte[] plaintext = new byte[plaintextLength];
            System.arraycopy(dataBytes, 0, plaintext, 0, dataBytes.length);
              
            SecretKeySpec keyspec = new SecretKeySpec(key.getBytes(), "AES");
            IvParameterSpec ivspec = new IvParameterSpec(iv.getBytes());
 
            cipher.init(Cipher.ENCRYPT_MODE, keyspec, ivspec);
            byte[] encrypted = cipher.doFinal(plaintext);
 
            return Base64Helper.encode(encrypted).trim();
 
        } catch (Exception e) {
            e.printStackTrace();
            return null;
        }
    }
 
    /**
     * AES算法解密密文
     * @param data 密文
     * @param key 密钥，长度16
     * @param iv 偏移量，长度16
     * @return 明文
     */
    public static String decryptAES(String data,String key,String iv) throws Exception {
        try
        {
            byte[] encrypted1 = Base64Helper.decode(data);
              
            Cipher cipher = Cipher.getInstance("AES/CBC/PKCS5Padding"); //or NoPadding
            SecretKeySpec keyspec = new SecretKeySpec(key.getBytes(), "AES");
            IvParameterSpec ivspec = new IvParameterSpec(iv.getBytes());
              
            cipher.init(Cipher.DECRYPT_MODE, keyspec, ivspec);
 
            byte[] original = cipher.doFinal(encrypted1);
            String originalString = new String(original);
            return originalString.trim();
        }
        catch (Exception e) {
            e.printStackTrace();
            return null;
        }
    }
}

Java的Base64的帮助类。

import org.apache.commons.codec.binary.Base64;

public class Base64Helper {
    /**
     * 编码
     * @param byteArray
     * @return
     */
    public static String encode(byte[] byteArray) {
        return new String(new Base64().encode(byteArray));
    }
    
    /**
     * 解码
     * @param base64EncodedString
     * @return
     */
    public static byte[] decode(String base64EncodedString) {
        return new Base64().decode(base64EncodedString);
    }
}

亲测可用。C#加密的的密文，Java里面用同样的密钥可以解密；而Java加密的密文，在C#里面用同样的密钥也可以成功解密。

C#测试结果：

 

 Java的测试结果：

 

 谁有更好的建议敬请留言。