首先我们加密的时候都是使用对称加密,就是加密解密都是使用一套秘钥
非对称加密是指加密解密使用不同的秘钥
说明:本次记录的加密思路是后台java生成1 加密模块 2 加密公钥 3 加密秘钥其中公钥用于对字符串进行加密,秘钥用于对字符串进行解密,每次http请求后台将新生产的加密模块和加密公钥传送的前台,秘钥保存在后台。当前台使用公钥加密后,将数据传送到后台,后台再使用之前保存的秘钥进行解密。
注意:每次生成的1 加密模块 2 加密公钥 3 加密秘钥都是配套的,不能同上一次的加密模块来解密这一次的密文
效果
前台加密
后台解密(注释写错了…)
工具类:用于数据转换
package com.fh.util;
public class HexUtil {
/**
* 二进制byte数组转十六进制byte数组
* byte array to hex
*
* @param b byte array
* @return hex string
*/
public static String byte2hex(byte[] b) {
StringBuilder hs = new StringBuilder();
String stmp;
for (int i = 0; i < b.length; i++) {
stmp = Integer.toHexString(b[i] & 0xFF).toUpperCase();
if (stmp.length() == 1) {
hs.append("0").append(stmp);
} else {
hs.append(stmp);
}
}
return hs.toString();
}
/**
* 十六进制byte数组转二进制byte数组
* hex to byte array
*
* @param hex hex string
* @return byte array
*/
public static byte[] hex2byte(String hex)
throws IllegalArgumentException{
if (hex.length() % 2 != 0) {
throw new IllegalArgumentException ("invalid hex string");
}
char[] arr = hex.toCharArray();
byte[] b = new byte[hex.length() / 2];
for (int i = 0, j = 0, l = hex.length(); i < l; i++, j++) {
String swap = "" + arr[i++] + arr[i];
int byteint = Integer.parseInt(swap, 16) & 0xFF;
b[j] = new Integer(byteint).byteValue();
}
return b;
}
public static String bytesToHexString(byte[] src){
StringBuilder stringBuilder = new StringBuilder("");
if (src == null || src.length <= 0) {
return null;
}
for (int i = 0; i < src.length; i++) {
int v = src[i] & 0xFF;
String hv = Integer.toHexString(v);
if (hv.length() < 2) {
stringBuilder.append(0);
}
stringBuilder.append(hv);
}
return stringBuilder.toString();
}
private static byte charToByte(char c) {
return (byte) "0123456789ABCDEF".indexOf(c);
}
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;
}
}
核心:RSA加密类
package com.fh.util;
import java.io.ByteArrayOutputStream;
import java.io.FileInputStream;
import java.io.FileOutputStream;
import java.io.ObjectInputStream;
import java.io.ObjectOutputStream;
import java.math.BigInteger;
import java.security.KeyFactory;
import java.security.KeyPair;
import java.security.KeyPairGenerator;
import java.security.NoSuchAlgorithmException;
import java.security.PrivateKey;
import java.security.PublicKey;
import java.security.SecureRandom;
import java.security.interfaces.RSAPrivateKey;
import java.security.interfaces.RSAPublicKey;
import java.security.spec.InvalidKeySpecException;
import java.security.spec.RSAPrivateKeySpec;
import java.security.spec.RSAPublicKeySpec;
import java.util.HashMap;
import java.util.Map;
import javax.crypto.Cipher;
/**
* RSA 工具类。提供加密,解密,生成密钥对等方法。
* 需要到 下载bcprov-jdk14-123.jar。
*
*/
public class RSAUtils {
private static final int MAX_ENCRYPT_BLOCK = 117; // RSA最大加密明文大小
private static final int MAX_DECRYPT_BLOCK = 128; // RSA最大解密密文大小
/**
* 生成公钥和私钥
*
* @throws NoSuchAlgorithmException
*/
public static KeyPair genRSAKeyPair() throws NoSuchAlgorithmException {
KeyPairGenerator keyPairGen = KeyPairGenerator.getInstance("RSA");
keyPairGen.initialize(1024);
return keyPairGen.generateKeyPair();
}
/**
* 使用模和指数生成RSA公钥
* 注意:【此代码用了默认补位方式,为RSA/None/PKCS1Padding,不同JDK默认的补位方式可能不同,如Android默认是RSA
* /None/NoPadding】
*
* @param modulus 模
* @param exponent 指数
* @return
*/
public static RSAPublicKey getPublicKey(String modulus, String exponent) {
try {
BigInteger b1 = new BigInteger(modulus, 16);
BigInteger b2 = new BigInteger(exponent, 16);
KeyFactory keyFactory = KeyFactory.getInstance("RSA");
RSAPublicKeySpec keySpec = new RSAPublicKeySpec(b1, b2);
return (RSAPublicKey) keyFactory.generatePublic(keySpec);
} catch (Exception e) {
e.printStackTrace();
return null;
}
}
/**
* 使用模和指数生成RSA私钥
* 注意:【此代码用了默认补位方式,为RSA/None/PKCS1Padding,不同JDK默认的补位方式可能不同,如Android默认是RSA
* /None/NoPadding】
*
* @param modulus 模
* @param exponent 指数
* @return
*/
public static RSAPrivateKey getPrivateKey(String modulus, String exponent) {
try {
BigInteger b1 = new BigInteger(modulus, 16);
BigInteger b2 = new BigInteger(exponent, 16);
KeyFactory keyFactory = KeyFactory.getInstance("RSA");
RSAPrivateKeySpec keySpec = new RSAPrivateKeySpec(b1, b2);
return (RSAPrivateKey) keyFactory.generatePrivate(keySpec);
} catch (Exception e) {
e.printStackTrace();
return null;
}
}
/**
* 公钥加密
*/
public static byte[] encryptByPublicKey(byte[] data, RSAPublicKey publicKey) throws Exception {
Cipher cipher = Cipher.getInstance("RSA");
cipher.init(Cipher.ENCRYPT_MODE, publicKey);
int inputLen = data.length;
try (ByteArrayOutputStream out = new ByteArrayOutputStream()) {
int offSet = 0;
byte[] cache;
int i = 0;
// 对数据分段加密
while (inputLen - offSet > 0) {
if (inputLen - offSet > MAX_ENCRYPT_BLOCK) {
cache = cipher.doFinal(data, offSet, MAX_ENCRYPT_BLOCK);
} else {
cache = cipher.doFinal(data, offSet, inputLen - offSet);
}
out.write(cache, 0, cache.length);
i++;
offSet = i * MAX_ENCRYPT_BLOCK;
}
return out.toByteArray();
}
}
/**
* 私钥解密
*/
public static String decryptByPrivateKey(byte[] encryptedData, RSAPrivateKey privateKey) throws Exception {
Cipher cipher = Cipher.getInstance("RSA");
cipher.init(Cipher.DECRYPT_MODE, privateKey);
int inputLen = encryptedData.length;
try (ByteArrayOutputStream out = new ByteArrayOutputStream()) {
int offSet = 0;
byte[] cache;
int i = 0;
// 对数据分段解密
while (inputLen - offSet > 0) {
if (inputLen - offSet > MAX_DECRYPT_BLOCK) {
cache = cipher.doFinal(encryptedData, offSet, MAX_DECRYPT_BLOCK);
} else {
cache = cipher.doFinal(encryptedData, offSet, inputLen - offSet);
}
out.write(cache, 0, cache.length);
i++;
offSet = i * MAX_DECRYPT_BLOCK;
}
return new String(out.toByteArray(), "utf-8");
}
}
/**
* ASCII码转BCD码
*/
public static byte[] ASCII_To_BCD(byte[] ascii, int asc_len) {
byte[] bcd = new byte[asc_len / 2];
int j = 0;
for (int i = 0; i < (asc_len + 1) / 2; i++) {
bcd[i] = asc_to_bcd(ascii[j++]);
bcd[i] = (byte) (((j >= asc_len) ? 0x00 : asc_to_bcd(ascii[j++])) + (bcd[i] << 4));
}
return bcd;
}
public static byte asc_to_bcd(byte asc) {
byte bcd;
if ((asc >= '0') && (asc <= '9'))
bcd = (byte) (asc - '0');
else if ((asc >= 'A') && (asc <= 'F'))
bcd = (byte) (asc - 'A' + 10);
else if ((asc >= 'a') && (asc <= 'f'))
bcd = (byte) (asc - 'a' + 10);
else
bcd = (byte) (asc - 48);
return bcd;
}
/**
* BCD转字符串
*/
public static String bcd2Str(byte[] bytes) {
char temp[] = new char[bytes.length * 2], val;
for (int i = 0; i < bytes.length; i++) {
val = (char) (((bytes[i] & 0xf0) >> 4) & 0x0f);
temp[i * 2] = (char) (val > 9 ? val + 'A' - 10 : val + '0');
val = (char) (bytes[i] & 0x0f);
temp[i * 2 + 1] = (char) (val > 9 ? val + 'A' - 10 : val + '0');
}
return new String(temp);
}
/**
* 拆分字符串
*/
public static String[] splitString(String string, int len) {
int x = string.length() / len;
int y = string.length() % len;
int z = 0;
if (y != 0) {
z = 1;
}
String[] strings = new String[x + z];
String str = "";
for (int i = 0; i < x + z; i++) {
if (i == x + z - 1 && y != 0) {
str = string.substring(i * len, i * len + y);
} else {
str = string.substring(i * len, i * len + len);
}
strings[i] = str;
}
return strings;
}
/**
* 拆分数组
*/
public static byte[][] splitArray(byte[] data, int len) {
int x = data.length / len;
int y = data.length % len;
int z = 0;
if (y != 0) {
z = 1;
}
byte[][] arrays = new byte[x + z][];
byte[] arr;
for (int i = 0; i < x + z; i++) {
arr = new byte[len];
if (i == x + z - 1 && y != 0) {
System.arraycopy(data, i * len, arr, 0, y);
} else {
System.arraycopy(data, i * len, arr, 0, len);
}
arrays[i] = arr;
}
return arrays;
}
//String 解密
public static String Decrypt(String str,String mou,String m) throws Exception{
//模hex
String modulus =mou;
//私钥指数hex
String private_exponent = m;
RSAPrivateKey priKey = getPrivateKey(modulus, private_exponent);
return decryptByPrivateKey(HexUtil.hexStringToBytes(str), priKey);
}
//获取模块信息
public static Map getModulus () throws NoSuchAlgorithmException{
KeyPair keyPair = genRSAKeyPair();
Map map = new HashMap();
//生成公钥和私钥
RSAPublicKey publicKey = (RSAPublicKey) keyPair.getPublic();
RSAPrivateKey privateKey = (RSAPrivateKey) keyPair.getPrivate();
//模hex
String modulus = publicKey.getModulus().toString(16);
//公钥指数hex
String public_exponent = publicKey.getPublicExponent().toString(16);
//私钥指数hex
String private_exponent = privateKey.getPrivateExponent().toString(16);
map.put("g", public_exponent);
map.put("m", private_exponent);
map.put("modu", modulus);
return map;
}
public static void main(String[] args) throws Exception {
KeyPair keyPair = genRSAKeyPair();
//生成公钥和私钥
RSAPublicKey publicKey = (RSAPublicKey) keyPair.getPublic();
RSAPrivateKey privateKey = (RSAPrivateKey) keyPair.getPrivate();
//模hex
String modulus = publicKey.getModulus().toString(16);
//公钥指数hex
String public_exponent = publicKey.getPublicExponent().toString(16);
//私钥指数hex
String private_exponent = privateKey.getPrivateExponent().toString(16);
System.out.println("public_modulus: " + modulus);
System.out.println("public_exponent: " + public_exponent);
System.out.println("private_exponent: " + private_exponent);
//明文
String plaintStr = "123456";
System.out.println("plaintStr: " + plaintStr);
//使用模和指数生成公钥和私钥
RSAPublicKey pubKey = getPublicKey(modulus, public_exponent);
RSAPrivateKey priKey = getPrivateKey(modulus, private_exponent);
//公钥加密后的密文
byte[] encryptStr = encryptByPublicKey(plaintStr.getBytes("utf-8"), pubKey);
System.out.println("encryptStr: " + HexUtil.bytesToHexString(encryptStr));
String jmh = HexUtil.bytesToHexString(encryptStr);
System.out.println("start");
//私钥解密后的明文
System.out.println("decryptStr: " + decryptByPrivateKey(HexUtil.hexStringToBytes(jmh), priKey));
}
}
业务逻辑类
//1
//声明加密秘钥
private static String m;
//声明加密模块
private static String mou;
//2
//调用RSA工具类的getModulus方法获取配套的公钥,秘钥,和加密模块信息,并将公钥和加密模块传送到前台,秘钥和加密模块
//保存到后台
@ResponseBody
@RequestMapping(value = "/getMoudle", method = RequestMethod.POST)
public Object getMoudle() throws NoSuchAlgorithmException {
Map jmInfo = RSAUtils.getModulus();
String my = jmInfo.getString("m");
m = my;
mou = jmInfo.getString("modu");
return jmInfo;
}
//3
//使用之前保存的加密模块和秘钥进行解密
SAUtils.Decrypt(参数,mou,m)
4 js
//1
//映入js包
<script language="JavaScript" type="text/javascript" src="http://www-cs-students.stanford.edu/~tjw/jsbn/jsbn.js"></script>
<script language="JavaScript" type="text/javascript" src="http://www-cs-students.stanford.edu/~tjw/jsbn/jsbn2.js"></script>
<script language="JavaScript" type="text/javascript" src="http://www-cs-students.stanford.edu/~tjw/jsbn/prng4.js"></script>
<script language="JavaScript" type="text/javascript" src="http://www-cs-students.stanford.edu/~tjw/jsbn/rng.js"></script>
<script language="JavaScript" type="text/javascript" src="http://www-cs-students.stanford.edu/~tjw/jsbn/rsa.js"></script>
<script language="JavaScript" type="text/javascript" src="http://www-cs-students.stanford.edu/~tjw/jsbn/rsa2.js"></script>
//2声明加密对象
var RSADo = {
"modulus":"",
"publicExponent":""}
//2获取加密信息
function getModule(){
mui.ajax("..../....", {
data: {
},
dataType: 'json', //服务器返回json格式数据
async: false,
type: 'post', //HTTP请求类型
timeout: 10000, //超时时间设置为10秒;
success: function (data) {
RSADo.modulus = data.modu;
RSADo.publicExponent = data.g;
privateKey = data.m;
},
error: function (xhr, type, errorThrown) {
}
});
/* var str = "12345"
var rsa = new RSAKey()
rsa.setPublic(RSADo.modulus, RSADo.publicExponent)
var encryptStr = rsa.encrypt(str);
console.log('modulus:', RSADo.modulus);
console.log('明文(explain):', str)
console.log('加密后(encrypt):', encryptStr)
// 解密
rsa.setPrivate(RSADo.modulus, RSADo.publicExponent, privateKey)
var decryptStr = rsa.decrypt(encryptStr)
console.log('解密私钥:', privateKey)
console.log('解密后(decrypt)', decryptStr)*/
})
//公钥加密方法
function encryption(str){
// 实例化js的RSA对象生成
var rsa = new RSAKey()
rsa.setPublic(RSADo.modulus, RSADo.publicExponent)
var encryptStr = rsa.encrypt(str);
return encryptStr;
}
当然前台后台都是可以单独加密解密的。只要使用配套的加密信息就可以了