不可逆加密
MD5加密
package com.system.util; import java.security.MessageDigest; public class MD5Util { public final static String MD5(String s) { char hexDigits[]={'0','1','2','3','4','5','6','7','8','9','A','B','C','D','E','F'}; try { byte[] btInput = s.getBytes(); // 获得MD5摘要算法 MessageDigest 对象 MessageDigest mdInst = MessageDigest.getInstance("MD5"); // 使用指定的字节更新摘要 mdInst.update(btInput); // 获得密文 byte[] md = mdInst.digest(); // 把密文转换成十六进制的字符串形式 int j = md.length; char str[] = new char[j * 2]; int k = 0; for (int i = 0; i < j; i++) { byte byte0 = md[i]; str[k++] = hexDigits[byte0 >>> 4 & 0xf]; str[k++] = hexDigits[byte0 & 0xf]; } return new String(str); } catch (Exception e) { e.printStackTrace(); return null; } } }
对称加密
DES加密
package com.gmtx.system.tools; import java.security.SecureRandom; import java.util.Random; import javax.crypto.*; import javax.crypto.spec.DESKeySpec; import org.apache.commons.codec.binary.Base64; /** DES加密介绍 DES是一种对称加密算法，所谓对称加密算法即：加密和解密使用相同密钥的算法。DES加密算法出自IBM的研究， 后来被美国政府正式采用，之后开始广泛流传，但是近些年使用越来越少，因为DES使用56位密钥，以现代计算能力， 24小时内即可被破解。虽然如此，在某些简单应用中，我们还是可以使用DES加密算法 注意：DES加密和解密过程中，密钥长度都必须是8的倍数 */ public class DES { public static void main(String[] args) throws Exception { //动态创建16位秘钥,可以写死 String password = createSecKey(16); System.out.println(password); String str = "测试内容"; /*测试加密*/ String rs = encrypt(str, password); System.out.println("加密后: "+rs); /*测试解密*/ String rs_des = decrypt(rs,password); System.out.println("解密后: "+rs_des); } private static String[] ss = { "a", "b", "c", "d", "e", "f", "g", "h", "i", "j", "k", "l", "m", "n", "o", "p", "q", "r", "s", "t", "u", "v", "w", "x", "y", "z", "A", "B", "C", "D", "E", "F", "G", "H", "I", "J", "K", "L", "M", "N", "O", "P", "Q", "R", "S", "T", "U", "V", "W", "X", "Y", "Z", "1", "2", "3", "4", "5", "6", "7", "8", "9", "0" }; /** * 根据长度生成密钥 * @param length 长度须是8 * @return * @throws Exception */ public static String createSecKey(int length) { if (length % 8 != 0) { return null; } String result = ""; for (int i = 0; i < length; i++) { Random r = new Random(); int n = r.nextInt(ss.length); result += ss[n]; } return result; } /** * 加密 * @param data 待加密数据 * @param key 秘钥 * @return * @throws Exception */ public static String encrypt(String data, String key){ try { byte[] bt = encrypt(data.getBytes("utf-8"), key); String strs = Base64.encodeBase64String(bt); return strs; } catch (Exception ex) { ex.printStackTrace(); } return ""; } /** * 解密 * @param data 待解密字符串 * @param key 秘钥 * @return * @throws Exception */ public static String decrypt(String data, String key) throws Exception { byte[] buf = Base64.decodeBase64(data); byte[] bt = decrypt(buf, key); return new String(bt, "UTF-8"); } /** * 加密 - byte数组 * @param datasource * @param password * @return */ private static byte[] encrypt(byte[] datasource, String password) { try { SecureRandom random = new SecureRandom(); DESKeySpec desKey = new DESKeySpec(password.getBytes()); //创建一个密匙工厂，然后用它把DESKeySpec转换成SecretKey SecretKeyFactory keyFactory = SecretKeyFactory.getInstance("DES"); SecretKey securekey = keyFactory.generateSecret(desKey); //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, random); //现在，获取数据并加密 //正式执行加密操作 return cipher.doFinal(datasource); } catch (Throwable e) { e.printStackTrace(); } return null; } /** * 解密 - byte数组 * @param src 加密字符串的二进制数组 * @param password 解密密码 * @return 原字符串的二进制数组 * @throws Exception */ private static byte[] decrypt(byte[] src, String password) throws Exception { //DES算法要求有一个可信任的随机数源 SecureRandom random = new SecureRandom(); //创建一个DESKeySpec对象 DESKeySpec desKey = new DESKeySpec(password.getBytes()); //创建一个密匙工厂 SecretKeyFactory keyFactory = SecretKeyFactory.getInstance("DES"); //将DESKeySpec对象转换成SecretKey对象 SecretKey securekey = keyFactory.generateSecret(desKey); //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, random); // 真正开始解密操作 return cipher.doFinal(src); } }
测试内容
