学习加密(三)spring boot 使用RSA非对称加密,前后端传递参数加解密

1.前面一篇是AES对称加密写了一个demo,为了后面的两者结合使用,今天去了解学习了下RSA非对称加密.

2.这是百度百科对(对称加密丶非对称加密)的解释:

(1)对称加密算法在加密和解密时使用的是同一个秘钥。

(2)非对称加密算法需要两个密钥来进行加密和解密，这两个秘钥是公开密钥（public key，简称公钥）和私有密钥（private key，简称私钥）。

大致思路:

     (1)服务端利用RSA创建一对公私钥,服务端存储私钥,将公钥给客户端
     (2)每次请求前,将明文数据利用公钥进行加密,然后将密文传递给服务端
     (3)服务端拿到密文,利用私钥进行解密,得到明文数据,然后进行业务处理

ps: 如果想做到返回参数也进行加密,那么两个方法,
     (1)客户端或服务端创建一对公私钥,然后将公私钥传递给服务端或客户端,(这样就可以使用公钥加密,私钥解密了),但是私钥放在客户端就违背了非对称加密(RSA)的原则性了,
     (2)客户端,创建一对公私钥,服务端在重新创建新的一对公私钥,互相各拿对方的公钥,这样就可以进行传参的加密,解密,和响应数据的加解密!!!
     但是为了解决RSA加解密性能问题,请看下篇文章RSA+AES(动态获取key)进行混合加密

使用非对称加密(RSA)实践(采用前端加密,后端解密,后端并不返回加密数据):

1.创建spring boot项目,导入相关依赖
2.编写加密工具类
3.编写自定义注解(让加解密细粒度)
4.编写自定义RsaDecodeRequestAdvice
5.创建controller
6.创建jsp或者html,引入js(加密和解密的通用js)
ps:因为这里没https证书,所有使用http, 考虑到前后端分离,使用json来传递数据

第一步: 略,不会的请自行百度spring boot项目如何创建!
第二步:

import org.apache.commons.codec.binary.Base64;

import java.io.ByteArrayOutputStream;
import java.security.Key;
import java.security.KeyFactory;
import java.security.KeyPair;
import java.security.KeyPairGenerator;
import java.security.PrivateKey;
import java.security.PublicKey;
import java.security.Signature;
import java.security.interfaces.RSAPrivateKey;
import java.security.interfaces.RSAPublicKey;
import java.security.spec.PKCS8EncodedKeySpec;
import java.security.spec.X509EncodedKeySpec;
import java.util.HashMap;
import java.util.Map;

import javax.crypto.Cipher;

/** */
/**
* <p>
* RSA公钥/私钥/签名工具包
* </p>
* <p>
* 罗纳德·李维斯特（Ron [R]ivest）、阿迪·萨莫尔（Adi [S]hamir）和伦纳德·阿德曼（Leonard [A]dleman）
* </p>
* <p>
* 字符串格式的密钥在未在特殊说明情况下都为BASE64编码格式<br/>
* 由于非对称加密速度极其缓慢，一般文件不使用它来加密而是使用对称加密，<br/>
* 非对称加密算法可以用来对对称加密的密钥加密，这样保证密钥的安全也就保证了数据的安全
* </p>
*
* @author monkey
* @date 2018-10-29
*/
public class RSAUtils {

   /** */
   /**
   * 加密算法RSA
   */
   public static final String KEY_ALGORITHM = "RSA";

   /** */
   /**
   * 签名算法
   */
   public static final String SIGNATURE_ALGORITHM = "MD5withRSA";

   /** */
   /**
   * 获取公钥的key
   */
   private static final String PUBLIC_KEY = "RSAPublicKey";

   /** */
   /**
   * 获取私钥的key
   */
   private static final String PRIVATE_KEY = "RSAPrivateKey";

   /** */
   /**
   * RSA最大加密明文大小
   */
   private static final int MAX_ENCRYPT_BLOCK = 117;

   /** */
   /**
   * RSA最大解密密文大小
   */
   private static final int MAX_DECRYPT_BLOCK = 128;

   /** */
   /**
   * RSA 位数如果采用2048 上面最大加密和最大解密则须填写: 245 256
   */
   private static final int INITIALIZE_LENGTH = 1024;

   /** */
   /**
   * <p>
   * 生成密钥对(公钥和私钥)
   * </p>
   *
   * @return
   * @throws Exception
   */
   public static Map<String, Object> genKeyPair() throws Exception {
       KeyPairGenerator keyPairGen = KeyPairGenerator.getInstance(KEY_ALGORITHM);
       keyPairGen.initialize(INITIALIZE_LENGTH);
       KeyPair keyPair = keyPairGen.generateKeyPair();
       RSAPublicKey publicKey = (RSAPublicKey) keyPair.getPublic();
       RSAPrivateKey privateKey = (RSAPrivateKey) keyPair.getPrivate();
       Map<String, Object> keyMap = new HashMap<String, Object>(2);
       keyMap.put(PUBLIC_KEY, publicKey);
       keyMap.put(PRIVATE_KEY, privateKey);
       return keyMap;
   }

   /** */
   /**
   * <p>
   * 用私钥对信息生成数字签名
   * </p>
   *
   * @param data
   * 已加密数据
   * @param privateKey
   * 私钥(BASE64编码)
   *
   * @return
   * @throws Exception
   */
   public static String sign(byte[] data, String privateKey) throws Exception {
       byte[] keyBytes = Base64.decodeBase64(privateKey);
       PKCS8EncodedKeySpec pkcs8KeySpec = new PKCS8EncodedKeySpec(keyBytes);
       KeyFactory keyFactory = KeyFactory.getInstance(KEY_ALGORITHM);
       PrivateKey privateK = keyFactory.generatePrivate(pkcs8KeySpec);
       Signature signature = Signature.getInstance(SIGNATURE_ALGORITHM);
       signature.initSign(privateK);
       signature.update(data);
       return Base64.encodeBase64String(signature.sign());
   }

   /** */
   /**
   * <p>
   * 校验数字签名
   * </p>
   *
   * @param data
   * 已加密数据
   * @param publicKey
   * 公钥(BASE64编码)
   * @param sign
   * 数字签名
   *
   * @return
   * @throws Exception
   *
   */
   public static boolean verify(byte[] data, String publicKey, String sign) throws Exception {
       byte[] keyBytes = Base64.decodeBase64(publicKey);
       X509EncodedKeySpec keySpec = new X509EncodedKeySpec(keyBytes);
       KeyFactory keyFactory = KeyFactory.getInstance(KEY_ALGORITHM);
       PublicKey publicK = keyFactory.generatePublic(keySpec);
       Signature signature = Signature.getInstance(SIGNATURE_ALGORITHM);
       signature.initVerify(publicK);
       signature.update(data);
       return signature.verify(Base64.decodeBase64(sign));
   }

   /** */
   /**
   * <P>
   * 私钥解密
   * </p>
   *
   * @param encryptedData
   * 已加密数据
   * @param privateKey
   * 私钥(BASE64编码)
   * @return
   * @throws Exception
   */
   public static byte[] decryptByPrivateKey(byte[] encryptedData, String privateKey) throws Exception {
       byte[] keyBytes = Base64.decodeBase64(privateKey);
       PKCS8EncodedKeySpec pkcs8KeySpec = new PKCS8EncodedKeySpec(keyBytes);
       KeyFactory keyFactory = KeyFactory.getInstance(KEY_ALGORITHM);
       Key privateK = keyFactory.generatePrivate(pkcs8KeySpec);
       Cipher cipher = Cipher.getInstance(keyFactory.getAlgorithm());
       cipher.init(Cipher.DECRYPT_MODE, privateK);
       int inputLen = encryptedData.length;
       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;
       }
       byte[] decryptedData = out.toByteArray();
       out.close();
       return decryptedData;
   }

   /** */
   /**
   * <p>
   * 公钥解密
   * </p>
   *
   * @param encryptedData
   * 已加密数据
   * @param publicKey
   * 公钥(BASE64编码)
   * @return
   * @throws Exception
   */
   public static byte[] decryptByPublicKey(byte[] encryptedData, String publicKey) throws Exception {
       byte[] keyBytes = Base64.decodeBase64(publicKey);
       X509EncodedKeySpec x509KeySpec = new X509EncodedKeySpec(keyBytes);
       KeyFactory keyFactory = KeyFactory.getInstance(KEY_ALGORITHM);
       Key publicK = keyFactory.generatePublic(x509KeySpec);
       Cipher cipher = Cipher.getInstance(keyFactory.getAlgorithm());
       cipher.init(Cipher.DECRYPT_MODE, publicK);
       int inputLen = encryptedData.length;
       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;
       }
       byte[] decryptedData = out.toByteArray();
       out.close();
       return decryptedData;
   }

   /** */
   /**
   * <p>
   * 公钥加密
   * </p>
   *
   * @param data
   * 源数据
   * @param publicKey
   * 公钥(BASE64编码)
   * @return
   * @throws Exception
   */
   public static byte[] encryptByPublicKey(byte[] data, String publicKey) throws Exception {
       byte[] keyBytes = Base64.decodeBase64(publicKey);
       X509EncodedKeySpec x509KeySpec = new X509EncodedKeySpec(keyBytes);
       KeyFactory keyFactory = KeyFactory.getInstance(KEY_ALGORITHM);
       Key publicK = keyFactory.generatePublic(x509KeySpec);
       // 对数据加密
       Cipher cipher = Cipher.getInstance(keyFactory.getAlgorithm());
       cipher.init(Cipher.ENCRYPT_MODE, publicK);
       int inputLen = data.length;
       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;
       }
       byte[] encryptedData = out.toByteArray();
       out.close();
       return encryptedData;
   }

   /** */
   /**
   * <p>
   * 私钥加密
   * </p>
   *
   * @param data
   * 源数据
   * @param privateKey
   * 私钥(BASE64编码)
   * @return
   * @throws Exception
   */
   public static byte[] encryptByPrivateKey(byte[] data, String privateKey) throws Exception {
       byte[] keyBytes = Base64.decodeBase64(privateKey);
       PKCS8EncodedKeySpec pkcs8KeySpec = new PKCS8EncodedKeySpec(keyBytes);
       KeyFactory keyFactory = KeyFactory.getInstance(KEY_ALGORITHM);
       Key privateK = keyFactory.generatePrivate(pkcs8KeySpec);
       Cipher cipher = Cipher.getInstance(keyFactory.getAlgorithm());
       cipher.init(Cipher.ENCRYPT_MODE, privateK);
       int inputLen = data.length;
       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;
       }
       byte[] encryptedData = out.toByteArray();
       out.close();
       return encryptedData;
   }

   /** */
   /**
   * <p>
   * 获取私钥
   * </p>
   *
   * @param keyMap
   * 密钥对
   * @return
   * @throws Exception
   */
   public static String getPrivateKey(Map<String, Object> keyMap) throws Exception {
       Key key = (Key) keyMap.get(PRIVATE_KEY);
       return Base64.encodeBase64String(key.getEncoded());
   }

   /** */
   /**
   * <p>
   * 获取公钥
   * </p>
   *
   * @param keyMap
   * 密钥对
   * @return
   * @throws Exception
   */
   public static String getPublicKey(Map<String, Object> keyMap) throws Exception {
       Key key = (Key) keyMap.get(PUBLIC_KEY);
       return Base64.encodeBase64String(key.getEncoded());
   }

   /**
   * java端公钥加密
   */
   public static String encryptedDataOnJava(String data, String PUBLICKEY) {
       try {
           data = Base64.encodeBase64String(encryptByPublicKey(data.getBytes(), PUBLICKEY));
       } catch (Exception e) {
           // TODO Auto-generated catch block
           e.printStackTrace();
       }
       return data;
   }

   /**
   * java端私钥解密
   */
   public static String decryptDataOnJava(String data, String PRIVATEKEY) {
       String temp = "";
       try {
           byte[] rs = Base64.decodeBase64(data);
           temp = new String(RSAUtils.decryptByPrivateKey(rs, PRIVATEKEY),"UTF-8");

       } catch (Exception e) {
           e.printStackTrace();
       }
       return temp;
   }

   public static void main(String[] args) throws Exception{

   }
}

第三步:

import org.springframework.web.bind.annotation.Mapping;

import java.lang.annotation.*;

/**
* @author monkey
* @desc 请求数据解密
* @date 2018/10/29 20:17
*/
@Target({ElementType.METHOD,ElementType.TYPE})
@Retention(RetentionPolicy.RUNTIME)
@Mapping
@Documented
public @interface RsaSecurityParameter {

/**
* 入参是否解密，默认解密
*/
boolean inDecode() default true;

/**
* 出参是否加密，默认加密
*/
boolean outEncode() default true;
}
第四步:

import com.monkey.springboot.demo.annotation.RsaSecurityParameter;
import com.monkey.springboot.demo.utils.RSAUtils;
import org.apache.commons.io.IOUtils;
import org.apache.commons.lang3.StringUtils;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
import org.springframework.core.MethodParameter;
import org.springframework.http.HttpHeaders;
import org.springframework.http.HttpInputMessage;
import org.springframework.http.converter.HttpMessageConverter;
import org.springframework.web.bind.annotation.ControllerAdvice;
import org.springframework.web.servlet.mvc.method.annotation.RequestBodyAdvice;

import java.io.IOException;
import java.io.InputStream;
import java.lang.reflect.Type;

/**
* @author monkey
* @desc 请求数据解密
* @date 2018/10/29 20:17
*/
@ControllerAdvice(basePackages = "com.monkey.springboot.demo.controller")
public class RsaDecodeRequestBodyAdvice implements RequestBodyAdvice {

private static final Logger logger = LoggerFactory.getLogger(RsaDecodeRequestBodyAdvice.class);

private static final String PRIVATE_KEY="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";

@Override
public boolean supports(MethodParameter methodParameter, Type type, Class<? extends HttpMessageConverter<?>> aClass) {
return true;
}

@Override
public Object handleEmptyBody(Object body, HttpInputMessage httpInputMessage, MethodParameter methodParameter, Type type, Class<? extends HttpMessageConverter<?>> aClass) {
return body;
}

@Override
public HttpInputMessage beforeBodyRead(HttpInputMessage inputMessage, MethodParameter methodParameter, Type type, Class<? extends HttpMessageConverter<?>> aClass) throws IOException {
try {
boolean encode = false;
if (methodParameter.getMethod().isAnnotationPresent(RsaSecurityParameter.class)) {
//获取注解配置的包含和去除字段
RsaSecurityParameter serializedField = methodParameter.getMethodAnnotation(RsaSecurityParameter.class);
//入参是否需要解密
encode = serializedField.inDecode();
}
if (encode) {
logger.info("对方法method :【" + methodParameter.getMethod().getName() + "】返回数据进行解密");
return new MyHttpInputMessage(inputMessage);
}else{
return inputMessage;
}
} catch (Exception e) {
e.printStackTrace();
logger.error("对方法method :【" + methodParameter.getMethod().getName() + "】返回数据进行解密出现异常："+e.getMessage());
return inputMessage;
}
}

@Override
public Object afterBodyRead(Object body, HttpInputMessage httpInputMessage, MethodParameter methodParameter, Type type, Class<? extends HttpMessageConverter<?>> aClass) {
return body;
}

class MyHttpInputMessage implements HttpInputMessage {
private HttpHeaders headers;

private InputStream body;

public MyHttpInputMessage(HttpInputMessage inputMessage) throws Exception {
this.headers = inputMessage.getHeaders();
String content = easpString(IOUtils.toString(inputMessage.getBody(),"utf-8"));
this.body = IOUtils.toInputStream(RSAUtils.decryptDataOnJava(content,PRIVATE_KEY));
}

@Override
public InputStream getBody() throws IOException {
return body;
}

@Override
public HttpHeaders getHeaders() {
return headers;
}

/**
*
* @param requestData
* @return
*/
public String easpString(String requestData){
if(requestData != null && !requestData.equals("")){
String s = "{\"requestData\":";
if(!requestData.startsWith(s)){
throw new RuntimeException("参数【requestData】缺失异常！");
}else{
int closeLen = requestData.length()-1;
int openLen = "{\"requestData\":".length();
String substring = StringUtils.substring(requestData, openLen, closeLen);
return substring;
}
}
return "";
}
}
}
第五步:

/**
* 跳转rsa页面
*
* @return
*/

@RequestMapping("/rsa")
public String goRsa() {
return "rsa";
}

/**
* RSA测试
*
* @return object
*/
@RequestMapping("/rsaTest")
@ResponseBody
@RsaSecurityParameter
public Persion rsaTest(@RequestBody Persion info) {
System.out.println(info.getName());
String content = "内容";
info.setName(content);
return info;
}
第六步:
只需要引入这两个js文件,然后自定义一个html,这里采用了thymeleaf模板引擎.具体语法自行百度,很简单!

<!DOCTYPE html>
<html lang="en" xmlns:th="http://www.thymeleaf.org">
<head>
<meta charset="UTF-8">
<title>RSA 加解密</title>
<script type="text/javascript" th:src="@{~/js/jquery-2.2.3.min.js}"></script>
<script type="text/javascript" th:src="@{~/js/jsencrypt.min.js}"></script>
</head>
<body>

<script type="text/javascript">
$(function() {
$("#bt").click(
function() {

var encrypt = new JSEncrypt();
encrypt.setPublicKey($("#publickey").val());
$.ajax({
type: "POST",
url:"/rsaTest",
data:"{\"requestData\":"+encrypt.encrypt(JSON.stringify({name:"好看"}))+"}",
dataType:'json',
contentType: "application/json",
success: function(result) {
alert("解密的名称：" + uncrypted);
}
});
});
});
</script>
<h2>公钥：</h2>
<textarea id="publickey" rows="5" cols="45">MIGfMA0GCSqGSIb3DQEBAQUAA4GNADCBiQKBgQCJ9s1qlOyv9qpuaTqauW6fUftzE50rVk3yVPZwv1aO1Ch/XSEz76xCwkyvqpaqceRXrPpdBmO5+ruJ+I8osOHo7L5GWEOcMOO+8izp9hXKBBrmRMD4Egpn00k9DhVIEKp/vyddZPS/doxB8onhN6poTJDLdFLFVEicMf52caN9GQIDAQAB
</textarea>
<input type="button" id="bt" value="提交" />
</body>
</html>