Java实现SSH模式加密

public byte[] request(String param, String resultType) {
  logger.info("请求参数：" + param);

  // 返回对象
  KeyResult keyResult = new KeyResult();

  try {
    // 先获取公钥
    if (resultType.equals(PUBLIC_KEY_RESULT_TYPE)) {

      Map keyMap = RSACoder.initKey();
      // 产生公钥和私钥
      privateKey = RSACoder.getPrivateKey(keyMap);

      keyResult.setKey(RSACoder.getPublicKey(keyMap));

      logger.info("公钥字符串：" + keyResult.getKey());
      logger.info("私钥字符串：" + privateKey);

    } else if (resultType.equals(ECHOSTR_RESULT_TYPE)) {

      // 设置客户端的口令信息
      byte[] paramByte = new BASE64Decoder().decodeBuffer(param);
      echoStr = new String(RSACoder.decryptByPrivateKey(paramByte, privateKey));

    } else {
      // 通过数据库获取交易所对应的权限信息.
      // 先将请求转换为byte数组，然后再进行解密，最后转换为字符串
      ExchangeInfo info = ExchangeInfo.dao.getInfoByName(new String(CryptUtil.decrypt(
          new BASE64Decoder().decodeBuffer(param), echoStr.getBytes())));

      String result = "";

      // 获取系统启用权限
      if (resultType.equals(PRIVILEGE_RESULT_TYPE)) {
        // 先判断使用权限

        // 在判断使用日期
        // 当前登录用登录时获取登录的当前日期和开始日期进行比较，然后计算还可以使用的日期
        long time = (new Date().getTime() / 1000) - string2DateInt(openday);
        // 换算成天数
        int day = (int) (time / (60 * 60 * 24));
        // 还可以使用的天数
        if (usedays - day > 0) {
          // 可以使用
          result = "1";
        } else {
          // 无法使用
          result = "0";
        }

      }

      keyResult.setResult(CryptUtil.encrypt(result.getBytes(), echoStr.getBytes()));
    }

    return JsonUtil.objectToByte(keyResult);
  } catch (Exception e) {
    logger.error("webservice出错了！！！！");
    logger.error(e.getMessage(), e);
  }

  return null;
}

public static boolean canRunForExchange(String resultType) {
  int i = 1;
  boolean result = false;

  while (true) {
    try {
      // webservice调用类
      ExchangeServiceProxy proxy = new ExchangeServiceProxy();
      BASE64Encoder encoder = new BASE64Encoder();

      // step1.获取service产生的公钥
      KeyResult keyResult = JsonUtil.byteToObject(proxy.request(null, PUBLIC_KEY_RESULT_TYPE),
          KeyResult.class);

      // step2.产生随机字符串，发送到webserivce
      String echoStr = StrUtil.getEchoStrByLength(10);
      byte[] echoByteParam = RSACoder.encryptByPublicKey(echoStr.getBytes(), keyResult.getKey());
      proxy.request(encoder.encode(echoByteParam), ECHOSTR_RESULT_TYPE);

      // step3.加密客户端请求信息，然后发送到webservice
      // 先加密为byte数组，然后转换成字符串
      byte[] results = proxy.request(
          encoder.encode(CryptUtil.encrypt(Constants.client_type.getBytes(), echoStr.getBytes())),
          resultType);
      keyResult = JsonUtil.byteToObject(results, KeyResult.class);

      // step4.通过口令解密服务端返回消息
      String respOnse= new String(CryptUtil.decrypt(keyResult.getResult(), echoStr.getBytes()));
      if (response.equals("1")) {
        result = true;
      }
      break;
    } catch (Exception e) {
      logger.debug("第" + i + "次加载webservice失败");
      i++;
      logger.error(e.getMessage(), e);

      if (i >= 10) {
        break;
      }
    }
  }

  return result;
}

package com.honzh.socket.util;

import javax.crypto.Cipher;
import javax.crypto.SecretKey;
import javax.crypto.SecretKeyFactory;
import javax.crypto.spec.DESKeySpec;
import javax.crypto.spec.IvParameterSpec;

public class CryptUtil {
  /** 
  * @Title: encrypt 
  * @Description: 加密
  * @param data
  * @param key
  * @return
  * @throws Exception
  */
  public static byte[] encrypt(byte[] data, byte[] key) throws Exception {
    key = get8(key);
    Cipher cipher = Cipher.getInstance("DES/CBC/PKCS5Padding");
    DESKeySpec desKeySpec = new DESKeySpec(key);
    SecretKeyFactory keyFactory = SecretKeyFactory.getInstance("DES");
    SecretKey secretKey = keyFactory.generateSecret(desKeySpec);
    IvParameterSpec iv = new IvParameterSpec(key);
    cipher.init(Cipher.ENCRYPT_MODE, secretKey, iv);
    return cipher.doFinal(data);
  }

  /** 
  * @Title: decrypt 
  * @Description: 解密
  * @param data
  * @param key
  * @return
  * @throws Exception
  */
  public static byte[] decrypt(byte[] data, byte[] key) throws Exception {
    key = get8(key);
    Cipher cipher = Cipher.getInstance("DES/CBC/PKCS5Padding");
    DESKeySpec desKeySpec = new DESKeySpec(key);
    SecretKeyFactory keyFactory = SecretKeyFactory.getInstance("DES");
    SecretKey secretKey = keyFactory.generateSecret(desKeySpec);
    IvParameterSpec iv = new IvParameterSpec(key);
    cipher.init(Cipher.DECRYPT_MODE, secretKey, iv);
    return cipher.doFinal(data);
  }

  private static byte[] get8(byte[] key) {
    byte[] key1 = new byte[8];
    for (int i = 0; i <8; i++) {
      key1[i] = key[i];
    }
    return key1;
  }

  public static String toHexString(byte[] data) {
    String s = "";
    for (int i = 0; i