乐趣区

关于java:Spring-Boot-接口加解密新姿势来了

1. 介绍

在咱们日常的 Java 开发中,免不了和其余零碎的业务交互,或者微服务之间的接口调用

如果咱们想保障数据传输的平安,对接口出加入密,入参解密。

然而不想写反复代码,咱们能够提供一个通用 starter,提供通用加密解密性能

2. 前置常识

2.1 hutool-crypto 加密解密工具

hutool-crypto 提供了很多加密解密工具,包含对称加密,非对称加密,摘要加密等等,这不做具体介绍。

2.2 request 流只能读取一次的问题

2.2.1 问题:

在接口调用链中,request 的申请流只能调用一次,解决之后,如果之后还须要用到申请流获取数据,就会发现数据为空。

比方应用了 filter 或者 aop 在接口解决之前,获取了 request 中的数据,对参数进行了校验,那么之后就不能在获取 request 申请流了

2.2.2 解决办法

继承 HttpServletRequestWrapper,将申请中的流 copy 一份,复写getInputStream 和 getReader 办法供内部应用。每次调用后的 getInputStream 办法都是从复制进去的二进制数组中进行获取,这个二进制数组在对象存在期间统一存在。

应用 Filter 过滤器,在一开始,替换 request 为本人定义的能够屡次读取流的 request。

这样就实现了流的反复获取

InputStreamHttpServletRequestWrapper
package xyz.hlh.cryptotest.utils;

import org.apache.commons.io.IOUtils;

import javax.servlet.ReadListener;
import javax.servlet.ServletInputStream;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletRequestWrapper;
import java.io.BufferedReader;
import java.io.ByteArrayInputStream;
import java.io.ByteArrayOutputStream;
import java.io.IOException;
import java.io.InputStreamReader;

/**
 * 申请流反对屡次获取
 */
public class InputStreamHttpServletRequestWrapper extends HttpServletRequestWrapper {

    /**
     * 用于缓存输出流
     */
    private ByteArrayOutputStream cachedBytes;

    public InputStreamHttpServletRequestWrapper(HttpServletRequest request) {super(request);
    }

    @Override
    public ServletInputStream getInputStream() throws IOException {if (cachedBytes == null) {
            // 首次获取流时,将流放入 缓存输出流 中
            cacheInputStream();}

        // 从 缓存输出流 中获取流并返回
        return new CachedServletInputStream(cachedBytes.toByteArray());
    }

    @Override
    public BufferedReader getReader() throws IOException {return new BufferedReader(new InputStreamReader(getInputStream()));
    }

    /**
     * 首次获取流时,将流放入 缓存输出流 中
     */
    private void cacheInputStream() throws IOException {
        // 缓存输出流以便屡次读取。为了不便, 我应用 org.apache.commons IOUtils
        cachedBytes = new ByteArrayOutputStream();
        IOUtils.copy(super.getInputStream(), cachedBytes);
    }

    /**
     * 读取缓存的申请注释的输出流
     * <p>
     * 用于依据 缓存输出流 创立一个可返回的
     */
    public static class CachedServletInputStream extends ServletInputStream {

        private final ByteArrayInputStream input;

        public CachedServletInputStream(byte[] buf) {
            // 从缓存的申请注释创立一个新的输出流
            input = new ByteArrayInputStream(buf);
        }

        @Override
        public boolean isFinished() {return false;}

        @Override
        public boolean isReady() {return false;}

        @Override
        public void setReadListener(ReadListener listener) { }

        @Override
        public int read() throws IOException {return input.read();
        }
    }

}
HttpServletRequestInputStreamFilter
package xyz.hlh.cryptotest.filter;

import org.springframework.core.annotation.Order;
import org.springframework.stereotype.Component;
import xyz.hlh.cryptotest.utils.InputStreamHttpServletRequestWrapper;

import javax.servlet.Filter;
import javax.servlet.FilterChain;
import javax.servlet.ServletException;
import javax.servlet.ServletRequest;
import javax.servlet.ServletResponse;
import javax.servlet.http.HttpServletRequest;
import java.io.IOException;

import static org.springframework.core.Ordered.HIGHEST_PRECEDENCE;

/**
 * @author HLH
 * @description:
 *      申请流转换为屡次读取的申请流 过滤器
 * @email 17703595860@163.com
 * @date : Created in 2022/2/4 9:58
 */
@Component
@Order(HIGHEST_PRECEDENCE + 1)  // 优先级最高
public class HttpServletRequestInputStreamFilter implements Filter {

    @Override
    public void doFilter(ServletRequest request, ServletResponse response, FilterChain chain) throws IOException, ServletException {

        // 转换为能够屡次获取流的 request
        HttpServletRequest httpServletRequest = (HttpServletRequest) request;
        InputStreamHttpServletRequestWrapper inputStreamHttpServletRequestWrapper = new InputStreamHttpServletRequestWrapper(httpServletRequest);

        // 放行
        chain.doFilter(inputStreamHttpServletRequestWrapper, response);
    }
}

2.3 SpringBoot 的参数校验 validation

Spring Boot 根底就不介绍了,举荐看这个收费教程:

https://github.com/javastacks/spring-boot-best-practice

为了缩小接口中,业务代码之前的大量冗余的参数校验代码

SpringBoot-validation提供了优雅的参数校验,入参都是实体类,在实体类字段上加上对应注解,就能够在进入办法之前,进行参数校验,如果参数谬误,会抛出谬误BindException,是不会进入办法的。

这种办法,必须要求在接口参数上加注解 @Validated 或者是@Valid

然而很多清空下,咱们心愿在代码中调用某个实体类的校验性能,所以须要如下工具类。

ParamException
package xyz.hlh.cryptotest.exception;

import lombok.Getter;

import java.util.List;

/**
 * @author HLH
 * @description 自定义参数异样
 * @email 17703595860@163.com
 * @date Created in 2021/8/10 下午 10:56
 */
@Getter
public class ParamException extends Exception {

    private final List<String> fieldList;
    private final List<String> msgList;

    public ParamException(List<String> fieldList, List<String> msgList) {
        this.fieldList = fieldList;
        this.msgList = msgList;
    }
}
ValidationUtils
package xyz.hlh.cryptotest.utils;

import xyz.hlh.cryptotest.exception.CustomizeException;
import xyz.hlh.cryptotest.exception.ParamException;

import javax.validation.ConstraintViolation;
import javax.validation.Validation;
import javax.validation.Validator;
import java.util.LinkedList;
import java.util.List;
import java.util.Set;

/**
 * @author HLH
 * @description 验证工具类
 * @email 17703595860@163.com
 * @date Created in 2021/8/10 下午 10:56
 */
public class ValidationUtils {private static final Validator VALIDATOR = Validation.buildDefaultValidatorFactory().getValidator();

    /**
     * 验证数据
     * @param object 数据
     */
    public static void validate(Object object) throws CustomizeException {Set<ConstraintViolation<Object>> validate = VALIDATOR.validate(object);

        // 验证后果异样
        throwParamException(validate);
    }

    /**
     * 验证数据(分组)
     * @param object 数据
     * @param groups 所在组
     */
    public static void validate(Object object, Class<?> ... groups) throws CustomizeException {Set<ConstraintViolation<Object>> validate = VALIDATOR.validate(object, groups);

        // 验证后果异样
        throwParamException(validate);
    }

    /**
     * 验证数据中的某个字段(分组)
     * @param object 数据
     * @param propertyName 字段名称
     */
    public static void validate(Object object, String propertyName) throws CustomizeException {Set<ConstraintViolation<Object>> validate = VALIDATOR.validateProperty(object, propertyName);

        // 验证后果异样
        throwParamException(validate);

    }

    /**
     * 验证数据中的某个字段(分组)
     * @param object 数据
     * @param propertyName 字段名称
     * @param groups 所在组
     */
    public static void validate(Object object, String propertyName, Class<?> ... groups) throws CustomizeException {Set<ConstraintViolation<Object>> validate = VALIDATOR.validateProperty(object, propertyName, groups);

        // 验证后果异样
        throwParamException(validate);

    }

    /**
     * 验证后果异样
     * @param validate 验证后果
     */
    private static void throwParamException(Set<ConstraintViolation<Object>> validate) throws CustomizeException {if (validate.size() > 0) {List<String> fieldList = new LinkedList<>();
            List<String> msgList = new LinkedList<>();
            for (ConstraintViolation<Object> next : validate) {fieldList.add(next.getPropertyPath().toString());
                msgList.add(next.getMessage());
            }

            throw new ParamException(fieldList, msgList);
        }
    }

}

2.5 自定义 starter

自定义 starter 步骤

  • 创立工厂,编写性能代码
  • 申明主动配置类,把须要对外提供的对象创立好,通过配置类对立向外裸露
  • 在 resource 目录下筹备一个名为 spring/spring.factories 的文件,以 org.springframework.boot.autoconfigure.EnableAutoConfiguration 为 key,主动配置类为 value 列表,进行注册

2.6 RequestBodyAdvice 和 ResponseBodyAdvice

  • RequestBodyAdvice是对申请的 json 串进行解决,个别应用环境是解决接口参数的主动解密
  • ResponseBodyAdvice是对申请相应的 jsoin 传进行解决,个别用于相应后果的加密

3. 性能介绍

接口相应数据的时候,返回的是加密之后的数据 接口入参的时候,接管的是解密之后的数据,然而在进入接口之前,会主动解密,获得对应的数据

4. 性能细节

加密解密应用对称加密的 AES 算法,应用 hutool-crypto 模块进行实现

所有的实体类提取一个公共父类,蕴含属性工夫戳,用于加密数据返回之后的实效性,如果超过 60 分钟,那么其余接口将不进行解决。

如果接口加了加密注解 EncryptionAnnotation,并且返回对立的 json 数据 Result 类,则主动对数据进行加密。如果是继承了对立父类RequestBase 的数据,主动注入工夫戳,确保数据的时效性

如果接口加了解密注解DecryptionAnnotation,并且参数应用 RequestBody 注解标注,传入 json 应用对立格局 RequestData 类,并且内容是继承了蕴含工夫长的父类RequestBase,则主动解密,并且转为对应的数据类型

性能提供 Springboot 的 starter,实现开箱即用

5. 代码实现

https://gitee.com/springboot-hlh/spring-boot-csdn/tree/master…

5.1 我的项目构造

5.2 crypto-common

5.2.1 构造
5.3 crypto-spring-boot-starter
5.3.1 接口
5.3.2 重要代码

crypto.properties AES 须要的参数配置

# 模式    cn.hutool.crypto.Mode
crypto.mode=CTS
# 补码形式 cn.hutool.crypto.Mode
crypto.padding=PKCS5Padding
# 秘钥
crypto.key=testkey123456789
# 盐
crypto.iv=testiv1234567890

spring.factories 主动配置文件

org.springframework.boot.autoconfigure.EnableAutoConfiguration=\
xyz.hlh.crypto.config.AppConfig

CryptConfig AES 须要的配置参数

package xyz.hlh.crypto.config;

import cn.hutool.crypto.Mode;
import cn.hutool.crypto.Padding;
import lombok.Data;
import lombok.EqualsAndHashCode;
import lombok.Getter;
import org.springframework.boot.context.properties.ConfigurationProperties;
import org.springframework.context.annotation.Configuration;
import org.springframework.context.annotation.PropertySource;

import java.io.Serializable;

/**
 * @author HLH
 * @description: AES 须要的配置参数
 * @email 17703595860@163.com
 * @date : Created in 2022/2/4 13:16
 */
@Configuration
@ConfigurationProperties(prefix = "crypto")
@PropertySource("classpath:crypto.properties")
@Data
@EqualsAndHashCode
@Getter
public class CryptConfig implements Serializable {

    private Mode mode;
    private Padding padding;
    private String key;
    private String iv;

}

AppConfig 主动配置类

package xyz.hlh.crypto.config;

import cn.hutool.crypto.symmetric.AES;
import org.springframework.context.annotation.Bean;
import org.springframework.context.annotation.Configuration;

import javax.annotation.Resource;
import java.nio.charset.StandardCharsets;

/**
 * @author HLH
 * @description: 主动配置类
 * @email 17703595860@163.com
 * @date : Created in 2022/2/4 13:12
 */
@Configuration
public class AppConfig {

    @Resource
    private CryptConfig cryptConfig;

    @Bean
    public AES aes() {return new AES(cryptConfig.getMode(), cryptConfig.getPadding(), cryptConfig.getKey().getBytes(StandardCharsets.UTF_8), cryptConfig.getIv().getBytes(StandardCharsets.UTF_8));
    }

}

DecryptRequestBodyAdvice 申请主动解密

package xyz.hlh.crypto.advice;

import com.fasterxml.jackson.databind.ObjectMapper;
import lombok.SneakyThrows;
import org.apache.commons.lang3.StringUtils;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.core.MethodParameter;
import org.springframework.http.HttpInputMessage;
import org.springframework.http.converter.HttpMessageConverter;
import org.springframework.web.bind.annotation.ControllerAdvice;
import org.springframework.web.context.request.RequestAttributes;
import org.springframework.web.context.request.RequestContextHolder;
import org.springframework.web.context.request.ServletRequestAttributes;
import org.springframework.web.servlet.mvc.method.annotation.RequestBodyAdvice;
import xyz.hlh.crypto.annotation.DecryptionAnnotation;
import xyz.hlh.crypto.common.exception.ParamException;
import xyz.hlh.crypto.constant.CryptoConstant;
import xyz.hlh.crypto.entity.RequestBase;
import xyz.hlh.crypto.entity.RequestData;
import xyz.hlh.crypto.util.AESUtil;

import javax.servlet.ServletInputStream;
import javax.servlet.http.HttpServletRequest;
import java.io.IOException;
import java.lang.reflect.Type;

/**
 * @author HLH
 * @description: requestBody 主动解密
 * @email 17703595860@163.com
 * @date : Created in 2022/2/4 15:12
 */
@ControllerAdvice
public class DecryptRequestBodyAdvice implements RequestBodyAdvice {

    @Autowired
    private ObjectMapper objectMapper;

    /**
     * 办法上有 DecryptionAnnotation 注解的,进入此拦截器
     * @param methodParameter 办法参数对象
     * @param targetType 参数的类型
     * @param converterType 音讯转换器
     * @return true,进入,false,跳过
     */
    @Override
    public boolean supports(MethodParameter methodParameter, Type targetType, Class<? extends HttpMessageConverter<?>> converterType) {return methodParameter.hasMethodAnnotation(DecryptionAnnotation.class);
    }

    @Override
    public HttpInputMessage beforeBodyRead(HttpInputMessage inputMessage, MethodParameter parameter, Type targetType, Class<? extends HttpMessageConverter<?>> converterType) throws IOException {return inputMessage;}

    /**
     * 转换之后,执行此办法,解密,赋值
     * @param body spring 解析完的参数
     * @param inputMessage 输出参数
     * @param parameter 参数对象
     * @param targetType 参数类型
     * @param converterType 音讯转换类型
     * @return 实在的参数
     */
    @SneakyThrows
    @Override
    public Object afterBodyRead(Object body, HttpInputMessage inputMessage, MethodParameter parameter, Type targetType, Class<? extends HttpMessageConverter<?>> converterType) {

        // 获取 request
        RequestAttributes requestAttributes = RequestContextHolder.getRequestAttributes();
        ServletRequestAttributes servletRequestAttributes = (ServletRequestAttributes) requestAttributes;
        if (servletRequestAttributes == null) {throw new ParamException("request 谬误");
        }

        HttpServletRequest request = servletRequestAttributes.getRequest();

        // 获取数据
        ServletInputStream inputStream = request.getInputStream();
        RequestData requestData = objectMapper.readValue(inputStream, RequestData.class);

        if (requestData == null || StringUtils.isBlank(requestData.getText())) {throw new ParamException("参数谬误");
        }

        // 获取加密的数据
        String text = requestData.getText();

        // 放入解密之前的数据
        request.setAttribute(CryptoConstant.INPUT_ORIGINAL_DATA, text);

        // 解密
        String decryptText = null;
        try {decryptText = AESUtil.decrypt(text);
        } catch (Exception e) {throw new ParamException("解密失败");
        }

        if (StringUtils.isBlank(decryptText)) {throw new ParamException("解密失败");
        }

        // 放入解密之后的数据
        request.setAttribute(CryptoConstant.INPUT_DECRYPT_DATA, decryptText);

        // 获取后果
        Object result = objectMapper.readValue(decryptText, body.getClass());

        // 强制所有实体类必须继承 RequestBase 类,设置工夫戳
        if (result instanceof RequestBase) {
            // 获取工夫戳
            Long currentTimeMillis = ((RequestBase) result).getCurrentTimeMillis();
            // 有效期 60 秒
            long effective = 60*1000;

            // 时间差
            long expire = System.currentTimeMillis() - currentTimeMillis;

            // 是否在有效期内
            if (Math.abs(expire) > effective) {throw new ParamException("工夫戳不非法");
            }

            // 返回解密之后的数据
            return result;
        } else {throw new ParamException(String.format("申请参数类型:%s 未继承:%s", result.getClass().getName(), RequestBase.class.getName()));
        }
    }

    /**
     * 如果 body 为空,转为空对象
     * @param body spring 解析完的参数
     * @param inputMessage 输出参数
     * @param parameter 参数对象
     * @param targetType 参数类型
     * @param converterType 音讯转换类型
     * @return 实在的参数
     */
    @SneakyThrows
    @Override
    public Object handleEmptyBody(Object body, HttpInputMessage inputMessage, MethodParameter parameter, Type targetType, Class<? extends HttpMessageConverter<?>> converterType) {String typeName = targetType.getTypeName();
        Class<?> bodyClass = Class.forName(typeName);
        return bodyClass.newInstance();}
}

EncryptResponseBodyAdvice 相应主动加密

package xyz.hlh.crypto.advice;

import cn.hutool.json.JSONUtil;
import com.fasterxml.jackson.databind.ObjectMapper;
import lombok.SneakyThrows;
import org.apache.commons.lang3.StringUtils;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.core.MethodParameter;
import org.springframework.http.MediaType;
import org.springframework.http.ResponseEntity;
import org.springframework.http.converter.HttpMessageConverter;
import org.springframework.http.server.ServerHttpRequest;
import org.springframework.http.server.ServerHttpResponse;
import org.springframework.web.bind.annotation.ControllerAdvice;
import org.springframework.web.servlet.mvc.method.annotation.ResponseBodyAdvice;
import sun.reflect.generics.reflectiveObjects.ParameterizedTypeImpl;
import xyz.hlh.crypto.annotation.EncryptionAnnotation;
import xyz.hlh.crypto.common.entity.Result;
import xyz.hlh.crypto.common.exception.CryptoException;
import xyz.hlh.crypto.entity.RequestBase;
import xyz.hlh.crypto.util.AESUtil;

import java.lang.reflect.Type;

/**
 * @author HLH
 * @description:
 * @email 17703595860@163.com
 * @date : Created in 2022/2/4 15:12
 */
@ControllerAdvice
public class EncryptResponseBodyAdvice implements ResponseBodyAdvice<Result<?>> {

    @Autowired
    private ObjectMapper objectMapper;

    @Override
    public boolean supports(MethodParameter returnType, Class<? extends HttpMessageConverter<?>> converterType) {ParameterizedTypeImpl genericParameterType = (ParameterizedTypeImpl)returnType.getGenericParameterType();

        // 如果间接是 Result,则返回
        if (genericParameterType.getRawType() == Result.class && returnType.hasMethodAnnotation(EncryptionAnnotation.class)) {return true;}

        if (genericParameterType.getRawType() != ResponseEntity.class) {return false;}

        // 如果是 ResponseEntity<Result>
        for (Type type : genericParameterType.getActualTypeArguments()) {if (((ParameterizedTypeImpl) type).getRawType() == Result.class && returnType.hasMethodAnnotation(EncryptionAnnotation.class)) {return true;}
        }

        return false;
    }

    @SneakyThrows
    @Override
    public Result<?> beforeBodyWrite(Result<?> body, MethodParameter returnType, MediaType selectedContentType, Class<? extends HttpMessageConverter<?>> selectedConverterType, ServerHttpRequest request, ServerHttpResponse response) {

        // 加密
        Object data = body.getData();

        // 如果 data 为空,间接返回
        if (data == null) {return body;}

        // 如果是实体,并且继承了 Request,则放入工夫戳
        if (data instanceof RequestBase) {((RequestBase)data).setCurrentTimeMillis(System.currentTimeMillis());
        }

        String dataText = JSONUtil.toJsonStr(data);

        // 如果 data 为空,间接返回
        if (StringUtils.isBlank(dataText)) {return body;}

        // 如果位数小于 16,报错
        if (dataText.length() < 16) {throw new CryptoException("加密失败,数据小于 16 位");
        }

        String encryptText = AESUtil.encryptHex(dataText);

        return Result.builder()
                .status(body.getStatus())
                .data(encryptText)
                .message(body.getMessage())
                .build();}
}
5.4 crypto-test
5.4.1 构造

5.4.2 重要代码

application.yml 配置文件

spring:
  mvc:
    format:
      date-time: yyyy-MM-dd HH:mm:ss
      date: yyyy-MM-dd
  # 日期格式化
  jackson:
    date-format: yyyy-MM-dd HH:mm:ss

Teacher 实体类

package xyz.hlh.crypto.entity;

import lombok.AllArgsConstructor;
import lombok.Data;
import lombok.EqualsAndHashCode;
import lombok.NoArgsConstructor;
import org.hibernate.validator.constraints.Range;

import javax.validation.constraints.NotBlank;
import javax.validation.constraints.NotNull;
import java.io.Serializable;
import java.util.Date;

/**
 * @author HLH
 * @description: Teacher 实体类,应用 SpringBoot 的 validation 校验
 * @email 17703595860@163.com
 * @date : Created in 2022/2/4 10:21
 */
@Data
@NoArgsConstructor
@AllArgsConstructor
@EqualsAndHashCode(callSuper = true)
public class Teacher extends RequestBase implements Serializable {@NotBlank(message = "姓名不能为空")
    private String name;
    @NotNull(message = "年龄不能为空")
    @Range(min = 0, max = 150, message = "年龄不非法")
    private Integer age;
    @NotNull(message = "生日不能为空")
    private Date birthday;

}

TestController 测试 Controller

package xyz.hlh.crypto.controller;

import org.springframework.http.ResponseEntity;
import org.springframework.validation.annotation.Validated;
import org.springframework.web.bind.annotation.PostMapping;
import org.springframework.web.bind.annotation.RequestBody;
import org.springframework.web.bind.annotation.RestController;
import xyz.hlh.crypto.annotation.DecryptionAnnotation;
import xyz.hlh.crypto.annotation.EncryptionAnnotation;
import xyz.hlh.crypto.common.entity.Result;
import xyz.hlh.crypto.common.entity.ResultBuilder;
import xyz.hlh.crypto.entity.Teacher;

/**
 * @author HLH
 * @description: 测试 Controller
 * @email 17703595860@163.com
 * @date : Created in 2022/2/4 9:16
 */
@RestController
public class TestController implements ResultBuilder {

    /**
     * 间接返回对象,不加密
     * @param teacher Teacher 对象
     * @return 不加密的对象
     */
    @PostMapping("/get")
    public ResponseEntity<Result<?>> get(@Validated @RequestBody Teacher teacher) {return success(teacher);
    }

    /**
     * 返回加密后的数据
     * @param teacher Teacher 对象
     * @return 返回加密后的数据 ResponseBody<Result> 格局
     */
    @PostMapping("/encrypt")
    @EncryptionAnnotation
    public ResponseEntity<Result<?>> encrypt(@Validated @RequestBody Teacher teacher) {return success(teacher);
    }

    /**
     * 返回加密后的数据
     * @param teacher Teacher 对象
     * @return 返回加密后的数据 Result 格局
     */
    @PostMapping("/encrypt1")
    @EncryptionAnnotation
    public Result<?> encrypt1(@Validated @RequestBody Teacher teacher) {return success(teacher).getBody();}

    /**
     * 返回解密后的数据
     * @param teacher Teacher 对象
     * @return 返回解密后的数据
     */
    @PostMapping("/decrypt")
    @DecryptionAnnotation
    public ResponseEntity<Result<?>> decrypt(@Validated @RequestBody Teacher teacher) {return success(teacher);
    }

}

版权申明:本文为 CSDN 博主「HLH_2021」的原创文章,遵循 CC 4.0 BY-SA 版权协定,转载请附上原文出处链接及本申明。原文链接:https://blog.csdn.net/HLH_2021/article/details/122785888

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