import java.io.UnsupportedEncodingException;
import javax.crypto.Cipher;
import javax.crypto.SecretKey;
import javax.crypto.spec.SecretKeySpec;
public class DESUtils {
// 定义加密算法，有DES、DESede(即3DES)、Blowfish
public static final String Algorithm3DES = "DESede";// 0
public static final String AlgorithmDES = "DES";// 1
// 约定密钥
private static final byte[] FIX_KEY = { (byte) 0xFF,
(byte) 0xFF, (byte) 0xFF, (byte) 0xFF, (byte) 0xFF, (byte) 0xFF,
(byte) 0xFF, (byte) 0xFF, (byte) 0xFF, (byte) 0xFF, (byte) 0xFF,
(byte) 0xFF, (byte) 0xFF, (byte) 0xFF, (byte) 0xFF, (byte) 0xFF };
/**
*
* 使用约定密钥，加密方法 3des
*
* @param src
*
* @param Algorithm
* 算法
*
* @return
*/
public static byte[] encryptMode(byte[] src, String Algorithm) {
try {
SecretKey deskey = new SecretKeySpec(
Algorithm.equals(Algorithm3DES) ? build3DesKey(FIX_KEY) : build3DesKey(FIX_KEY), Algorithm); // 生成密钥
Cipher c1 = Cipher.getInstance(Algorithm);// 实例化负责加密/解密的Cipher工具类
c1.init(Cipher.ENCRYPT_MODE, deskey); // 初始化为加密模式
return c1.doFinal(src);
} catch (java.security.NoSuchAlgorithmException e1) {
e1.printStackTrace();
} catch (javax.crypto.NoSuchPaddingException e2) {
e2.printStackTrace();
} catch (java.lang.Exception e3) {
e3.printStackTrace();
}
return null;
}
/**
*
* 使用指定密钥的 加密
*
* @param src
*
* @param key
* 密钥
*
* @param Algorithm
* 算法
*
* @return
*/
public static byte[] encryptMode(byte[] src, byte[] key, String Algorithm) {
try {
SecretKey deskey = new SecretKeySpec(
Algorithm.equals(Algorithm3DES) ? build3DesKey(key) : build3DesKey(key), Algorithm); // 生成密钥
Cipher c1 = Cipher.getInstance(Algorithm);// 实例化负责加密/解密的Cipher工具类
c1.init(Cipher.ENCRYPT_MODE, deskey); // 初始化为加密模式
return c1.doFinal(src);
} catch (java.security.NoSuchAlgorithmException e1) {
e1.printStackTrace();
} catch (javax.crypto.NoSuchPaddingException e2) {
e2.printStackTrace();
} catch (java.lang.Exception e3) {
e3.printStackTrace();
}
return null;
}
/**
*
* 解密函数
*
*
*
* @param src
*
* 密文的字节数组
*
* @return
*/
public static byte[] decryptMode(byte[] src, String Algorithm) {
try {
SecretKey deskey = new SecretKeySpec(
build3DesKey(FIX_KEY), Algorithm);
Cipher c1 = Cipher.getInstance(Algorithm);
c1.init(Cipher.DECRYPT_MODE, deskey); // 初始化为解密模式
return c1.doFinal(src);
} catch (java.security.NoSuchAlgorithmException e1) {
e1.printStackTrace();
} catch (javax.crypto.NoSuchPaddingException e2) {
e2.printStackTrace();
} catch (java.lang.Exception e3) {
e3.printStackTrace();
}
return null;
}
/**
*
* 去掉java加密后会在后面自动填充的8位
*
* @param src
*
* @return
*/
public static byte[] withoutAutofill(byte[] src) {
byte[] newbyte = new byte[src.length - 8];
for (int i = 0; i < newbyte.length; i++) {
newbyte[i] = src[i];
}
return newbyte;
}
/*
*
* 根据字符串生成密钥字节数组
*
*
*
* @param keyStr 密钥字符串
*
*
*
* @return
*
*
*
* @throws UnsupportedEncodingException
*/
public static byte[] build3DesKey(byte[] temp)
throws UnsupportedEncodingException {
byte[] key = new byte[24]; // 声明一个24位的字节数组，默认里面都是0
System.arraycopy(temp, 0, key, 0, temp.length);
// 补充的8字节就是16字节密钥的前8位
for (int i = 0; i < 8; i++) {
key[16 + i] = temp[i];
}
return key;
}
/*
*
* 实现字节数组向十六进制的转换方法一
*/
public static String byte2HexStr(byte[] b) {
String hs = "";
String stmp = "";
for (int n = 0; n < b.length; n++) {
stmp = (Integer.toHexString(b[n] & 0XFF));
if (stmp.length() == 1)
hs = hs + "0" + stmp + " ";
else
hs = hs + stmp + " ";
}
return hs.toUpperCase();
}
/**
*
* Convert hex string to byte[]
*
* @param hexString
* the hex string
*
* @return byte[]
*/
public static byte[] hexStringToBytes(String hexString) {
if (hexString == null || hexString.equals("")) {
return null;
}
hexString = hexString.toUpperCase();
int length = hexString.length() / 2;
char[] hexChars = hexString.toCharArray();
byte[] d = new byte[length];
for (int i = 0; i < length; i++) {
int pos = i * 2;
d[i] = (byte) (charToByte(hexChars[pos]) << 4 | charToByte(hexChars[pos + 1]));
}
return d;
}
/**
*
* Convert char to byte
*
* @param c
* char
*
* @return byte
*/
private static byte charToByte(char c) {
return (byte) "0123456789ABCDEF".indexOf(c);
}
/**
*
* @param args
*/
public static void main(String[] args) {
String msg = new String("19840313");
System.out.println("【加密前】：" + msg);
// 加密
byte[] secretArr = DESUtils.encryptMode(msg.getBytes(), Algorithm3DES);
System.out.println("【加密后】：" + new String(withoutAutofill(secretArr)));
// 解密
byte[] myMsgArr = DESUtils.decryptMode(secretArr, Algorithm3DES);
System.out.println("【解密后】：" + new String(myMsgArr));
}
}
