DES算法要求有一个可信任的随机数源
import java.security.SecureRandom;
import javax.crypto.Cipher;
import javax.crypto.SecretKey;
import javax.crypto.SecretKeyFactory;
import javax.crypto.spec.DESKeySpec;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
public class PasswordEncryption {
??? private static final String PASSWORD_CRYPT_KEY = "_hrwps20090716pass_";
??? private final static String DES = "DES";
??? /**
???? *?
???? * 加密
???? *?
???? * @param src
???? *??????????? 数据源
???? *?
???? * @param key
???? *??????????? 密钥，长度必须是8的倍数
???? *?
???? * @return 返回加密后的数据
???? *?
???? * @throws Exception
???? *?
???? */
?????? public static byte[] encrypt(byte[] src, byte[] key) throws Exception {
??????
?????? // DES算法要求有一个可信任的随机数源
???????
??????? SecureRandom sr = new SecureRandom();
???????
??????? // 从原始密匙数据创建DESKeySpec对象
???????
??????? DESKeySpec dks = new DESKeySpec(key);
???????
??????? // 创建一个密匙工厂，然后用它把DESKeySpec转换成
???????
??????? // 一个SecretKey对象
???????
??????? SecretKeyFactory keyFactory = SecretKeyFactory.getInstance(DES);
???????
??????? SecretKey securekey = keyFactory.generateSecret(dks);
???????
??????? // Cipher对象实际完成加密操作
???????
??????? Cipher cipher = Cipher.getInstance(DES);
???????
??????? // 用密匙初始化Cipher对象
???????
??????? cipher.init(Cipher.ENCRYPT_MODE, securekey, sr);
???????
??????? // 现在，获取数据并加密
???????
??????? // 正式执行加密操作
???????
??????? return cipher.doFinal(src);
???????
?????? }
??????
?????? /**
??????? *?
??????? * 解密
??????? *?
??????? * @param src
??????? *??????????? 数据源
??????? *?
??????? * @param key
??????? *??????????? 密钥，长度必须是8的倍数
??????? *?
??????? * @return 返回解密后的原始数据
??????? *?
??????? * @throws Exception
??????? *?
??????? */
??????
?????? public static byte[] decrypt(byte[] src, byte[] key) throws Exception {
??????
??????? // DES算法要求有一个可信任的随机数源
???????
??????? SecureRandom sr = new SecureRandom();
???????
??????? // 从原始密匙数据创建一个DESKeySpec对象
???????
??????? DESKeySpec dks = new DESKeySpec(key);
???????
??????? // 创建一个密匙工厂，然后用它把DESKeySpec对象转换成
???????
??????? // 一个SecretKey对象
???????
??????? SecretKeyFactory keyFactory = SecretKeyFactory.getInstance(DES);
???????
??????? SecretKey securekey = keyFactory.generateSecret(dks);
???????
??????? // Cipher对象实际完成解密操作
???????
??????? Cipher cipher = Cipher.getInstance(DES);
???????
??????? // 用密匙初始化Cipher对象
???????
??????? cipher.init(Cipher.DECRYPT_MODE, securekey, sr);
???????
??????? // 现在，获取数据并解密
???????
??????? // 正式执行解密操作
???????
??????? return cipher.doFinal(src);
??????
?????? }
??????
?????? /**
??????? *?
??????? * 密码解密
??????? *?
??????? * @param data
??????? *?
??????? * @return
??????? *?
??????? * @throws Exception
??????? *?
??????? */
??????
?????? public final static String decrypt(String data) {
??????
?????? try {
??????
??????? return new String(decrypt(hex2byte(data.getBytes()), PASSWORD_CRYPT_KEY.getBytes()));
??????
?????? } catch (Exception e) {
??????
?????? }
??????
?????? return null;
??????
?????? }
??????
?????? /**
??????? *?
??????? * 密码加密
??????? *?
??????? * @param password
??????? *?
??????? * @return
??????? *?
??????? * @throws Exception
??????? *?
??????? */
??????
?????? public final static String encrypt(String password) {
??????
?????? try {
??????
?????? return byte2hex(encrypt(password.getBytes(), PASSWORD_CRYPT_KEY
?????? .getBytes()));
?????? } catch (Exception e) {
??????
?????? }
??????
?????? return null;
??????
?????? }
??????
?????? /**
??????? *?
??????? * 二行制转字符串
??????? *?
??????? * @param b
??????? *?
??????? * @return
??????? *?
??????? */
??????
?????? public static String byte2hex(byte[] b) {
??????
??????? String hs = "";
???????
??????? String stmp = "";
???????
??????? for (int n = 0; n? < b.length; n++) {
???????
??????? stmp = (java.lang.Integer.toHexString(b[n] & 0XFF));
???????
??????? if (stmp.length() == 1)
???????
??????? hs = hs + "0" + stmp;
???????
??????? else
???????
??????? hs = hs + stmp;
???????
??????? }
???????
??????? return hs.toUpperCase();
???????
?????? }
????????
?????? public static byte[] hex2byte(byte[] b) {
???????
??????? if ((b.length % 2) != 0)???
???????
??????? throw new IllegalArgumentException("长度不是偶数");
???????
??????? byte[] b2 = new byte[b.length / 2];
???????
??????? for (int n = 0; n? < b.length; n += 2) {
???????
??????? String item = new String(b, n, 2);
???????
??????? b2[n / 2] = (byte) Integer.parseInt(item, 16);
???????
?????? }
??????
?????? return b2;??
?????? }
???
??? /**
???? * 获得一个随机的加密密码
???? * @param minLen:密码的最小长度
???? * @param maxLen:密码的最大长度
???? * @return
???? */
??? public String getRandomEncryptPassword(int minLen,int maxLen){
??????? String randPassword="";
??????? String randChar="abcdefghijklmnopqrstuvwxyz1234567890ABCDEFGHIJKLMNOPQRSTUVWXYZ";
??????? int randNum=(int)(Math.random()*(maxLen-minLen+1))+minLen;? //密码的随机长度(minLen<=length<=maxLen)
??????? for(int i=0;i<randNum;i++){
??????????? int randCharIndex=(int)(Math.random()*randChar.length());
??????????? randPassword=randPassword+randChar.charAt(randCharIndex);
??????? }
??????? String encryptPassword=this.encrypt(randPassword);
??????? return encryptPassword;
??? }
//??? public ActionForward doUserPasswordChange(ActionMapping mapping, ActionForm form,
//??????????? HttpServletRequest request, HttpServletResponse response) {
//???????
//??????? String password=request.getParameter("oldpass");
//??????? String newPassword=request.getParameter("confirmPassword");
//??????? TSmUser userLogin=(TSmUser) request.getSession().getAttribute("loginUser");
//??????? PasswordEncryption passWordEncry = new PasswordEncryption();
//??????? if(!userLogin.getUserPassword().equals(passWordEncry.encrypt(password.trim()))){
//??????????? request.getSession().setAttribute("msgs", "校验输入的旧密码错误");
//??????????? return mapping.findForward("change");
//??????? }else if(userLogin.getUserPassword().equals(passWordEncry.encrypt(newPassword.trim()))){
//??????????? request.getSession().setAttribute("msgs", "输入的新密码于旧密码相同");
//??????????? return mapping.findForward("change");
//??????? }else{
//??????????? userLogin.setUserPassword(passWordEncry.encrypt(newPassword.trim()));
//??????????? try{
//??????????? tsmuserImpl.update(userLogin);
//??????????? }catch(Exception e){
//??????????????? request.getSession().setAttribute("msgs", "修改密码失败");
//??????????????? return mapping.findForward("change");
//??????????? }
//??????????? return mapping.findForward("success");
//??????? }
//??? }
???
??? public static void main(String[] args) {
??????? String s=PasswordEncryption.decrypt("4094D62D6C8C89C7");
??????? System.out.println(s);
??? }
}
