AES加、解密算法工具类

import org.apache.commons.codec.binary.Base64;
import org.apache.commons.codec.digest.DigestUtils;
import javax.crypto.Cipher;
import javax.crypto.spec.IvParameterSpec;
import javax.crypto.spec.SecretKeySpec;
import java.nio.charset.StandardCharsets;
import java.security.SecureRandom;
import java.util.Random;

/**

• AES加、解密算法工具类
  */
  public class AesUtil {

  /**

  • 内部固定key
  • /
    public static final String internalFixedKey=“123qazwsx”;
    /*
  • 加密算法AES
    */
    private static final String KEY_ALGORITHM = “AES”;

  /**

  • key的长度，Wrong key size: must be equal to 128, 192 or 256
  • 传入时需要16、24、36
    */
    private static final Integer KEY_LENGTH = 16 * 8;

  /**

  • 算法名称/加密模式/数据填充方式
  • 默认：AES/ECB/PKCS5Padding
    */
    private static final String ALGORITHMS = “AES/CBC/PKCS5Padding”;

  /**

  • 后端AES的key，由静态代码块赋值
    */
    public static String key;

  /**

  • 不能在代码中创建
  • JceSecurity.getVerificationResult 会将其put进 private static final Map<Provider,Object>中，导致内存缓便被耗尽
    */
    //private static final BouncyCastleProvider PROVIDER = new BouncyCastleProvider();

  static {
  key = getKey();
  }

  /**

  • 获取key
    */
    public static String getKey() {
    StringBuilder uid = new StringBuilder();
    //产生16位的强随机数
    Random rd = new SecureRandom();
    for (int i = 0; i < KEY_LENGTH / 8; i++) {
    //产生0-2的3位随机数
    int type = rd.nextInt(3);
    switch (type) {
    case 0:
    //0-9的随机数
    uid.append(rd.nextInt(10));
    break;
    case 1:
    //ASCII在65-90之间为大写,获取大写随机
    uid.append((char) (rd.nextInt(25) + 65));
    break;
    case 2:
    //ASCII在97-122之间为小写，获取小写随机
    uid.append((char) (rd.nextInt(25) + 97));
    break;
    default:
    break;
    }
    }
    return uid.toString();
    }

  /**

  • 加密

  • @param content 加密的字符串

  • @param encryptKey key值
    */
    public static String encrypt(String content, String encryptKey) throws Exception {
    //设置Cipher对象
    Cipher cipher = Cipher.getInstance(ALGORITHMS);
    byte[] initParam = internalFixedKey.getBytes();
    IvParameterSpec ivParameterSpec = new IvParameterSpec(initParam);
    cipher.init(Cipher.ENCRYPT_MODE, new SecretKeySpec(encryptKey.getBytes(), KEY_ALGORITHM), ivParameterSpec);

    //调用doFinal
    // 转base64
    return Base64.encodeBase64String(cipher.doFinal(content.getBytes(StandardCharsets.UTF_8)));

  }

  /**

  • 解密

  • @param encryptStr 解密的字符串

  • @param decryptKey 解密的key值
    */
    public static String decrypt(String encryptStr, String decryptKey) throws Exception {
    //base64格式的key字符串转byte
    byte[] decodeBase64 = Base64.decodeBase64(encryptStr);
    byte[] initParam = internalFixedKey.getBytes();
    IvParameterSpec ivParameterSpec = new IvParameterSpec(initParam);
    //设置Cipher对象
    Cipher cipher = Cipher.getInstance(ALGORITHMS);
    cipher.init(Cipher.DECRYPT_MODE, new SecretKeySpec(decryptKey.getBytes(), KEY_ALGORITHM), ivParameterSpec);

    //调用doFinal解密
    return new String(cipher.doFinal(decodeBase64),“UTF-8”);
    }

  /**

  • MD5验证方法
  • @param text 明文
  • @param key 密钥
  • @param md5 密文
  • @return true/false
  • @throws Exception
    */
    public boolean verify(String text, String md5) throws Exception {
    //根据传入的密钥进行验证
    String md5Text = md5(text);
    if(md5Text.equalsIgnoreCase(md5))
    {
    return true;
    }
    return false;
    }

  /**

  • MD5方法
  • @param text 明文
  • @param key 密钥
  • @return 密文
  • @throws Exception
    */
    public String md5(String text) throws Exception {
    //加密后的字符串
    String encodeStr= DigestUtils.md5Hex(text+“5WuQXkFmlhllL8Q3”);
    return encodeStr;
    }

  public static void main(String[] args) throws Exception {
  String a=“1234566768sdffsdfsdffs68”;
  String aj=encrypt(a,“5WuQXkFmlhllL8Q3”);
  System.out.println(aj);
  String jm=decrypt(aj,“5WuQXkFmlhllL8Q3”);
  System.out.println(jm);

  }
  }