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Spring Boot 接口加解密功能实现

2023-05-18 11:07

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介绍

在我们日常的Java开发中,免不了和其他系统的业务交互,或者微服务之间的接口调用;如果我们想保证数据传输的安全,对接口出参加密,入参解密。但是不想写重复代码,我们可以提供一个通用starter,提供通用加密解密功能。

基础知识

hutool-crypto加密解密工具

hutool-crypto提供了很多加密解密工具,包括对称加密,非对称加密,摘要加密等等,这不做详细介绍。

request流只能读取一次的问题

问题描述

在接口调用链中,request的请求流只能调用一次,处理之后,如果之后还需要用到请求流获取数据,就会发现数据为空。

比如使用了filter或者aop在接口处理之前,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请求流了。

解决办法

继承HttpServletRequestWrapper,将请求中的流copy一份,复写getInputStream和getReader方法供外部使用。每次调用后的getInputStream方法都是从复制出来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一致存在。

使用Filter过滤器,在一开始,替换request为自己定义的可以多次读取流的request。

下面这样就实现了流的重复获取:
工具类(InputStreamHttpServletRequestWrapper):

package com.mry.springboottools.validation;
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;

public class InputStreamHttpServletRequestWrapper extends HttpServletRequestWrapper {
    
    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 缓存输入流 中
            cacheInputStream();
        }
        // 从 缓存输入流 中获取流并返回
        return new CachedServletInputStream(cachedBytes.toByteArray());
    }
    @Override
    public BufferedReader getReader() throws IOException {
        return new BufferedReader(new InputStreamReader(getInputStream()));
    }
    
    private void cacheInputStream() throws IOException {
        // 缓存输入流以便多次读取。为了方便, 我使用 org.apache.commons IOUtils
        cachedBytes = new ByteArrayOutputStream();
        IOUtils.copy(super.getInputStream(), cachedBytes);
    }
    
    public static class CachedServletInputStream extends ServletInputStream {
        private final ByteArrayInputStream input;
        public CachedServletInputStream(byte[] buf) {
            // 从缓存的请求正文创建一个新的输入流
            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();
        }
    }
}

Filter过滤器(HttpServletRequestInputStreamFilter):

package com.mry.springboottools.validation;
import org.springframework.core.annotation.Order;
import org.springframework.stereotype.Component;
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;

@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 {
        // 转换为可以多次获取流的request
        HttpServletRequest httpServletRequest = (HttpServletRequest) request;
        InputStreamHttpServletRequestWrapper inputStreamHttpServletRequestWrapper = new InputStreamHttpServletRequestWrapper(httpServletRequest);
        // 放行
        chain.doFilter(inputStreamHttpServletRequestWrapper, response);
    }
}

SpringBoot的参数校验validation

为了减少接口中,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,就可以在进入方法之前,进行参数校验,如果参数错误,会抛出错误BindException,是不会进入方法的。

这种方法,必须要求在接口参数上加注解@Validated或者是@Valid

但是很多清空下,我们希望在代码中调用某个实体类的校验功能,所以需要如下工具类。

package com.mry.springboottools.validation;
import javax.validation.ConstraintViolation;
import javax.validation.Validation;
import javax.validation.Validator;
import java.util.LinkedList;
import java.util.List;
import java.util.Set;

public class ValidationUtils {
    private static final Validator VALIDATOR = Validation.buildDefaultValidatorFactory().getValidator();
    
    public static void validate(Object object) throws CustomizeException {
        Set<ConstraintViolation<Object>> validate = VALIDATOR.validate(object);
        // 验证结果异常
        throwParamException(validate);
    }
    
    public static void validate(Object object, Class<?> ... groups) throws CustomizeException {
        Set<ConstraintViolation<Object>> validate = VALIDATOR.validate(object, groups);
        // 验证结果异常
        throwParamException(validate);
    }
    
    public static void validate(Object object, String propertyName) throws CustomizeException {
        Set<ConstraintViolation<Object>> validate = VALIDATOR.validateProperty(object, propertyName);
        // 验证结果异常
        throwParamException(validate);
    }
    
    public static void validate(Object object, String propertyName, Class<?> ... groups) throws CustomizeException {
        Set<ConstraintViolation<Object>> validate = VALIDATOR.validateProperty(object, propertyName, groups);
        // 验证结果异常
        throwParamException(validate);
    }
    
    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);
        }
    }
}

自定义参数异常:

package com.mry.springboottools.validation;
import lombok.Getter;
import org.springframework.util.CollectionUtils;
import java.util.List;

@Getter
public class ParamException extends CustomizeException {
    private List<String> fieldList;
    private List<String> msgList;
    public ParamException(String message) {
        super(message);
    }
    public ParamException(String message, Throwable cause) {
        super(message, cause);
    }
    public ParamException(List<String> fieldList, List<String> msgList) throws CustomizeException {
        super(generatorMessage(fieldList, msgList));
        this.fieldList = fieldList;
        this.msgList = msgList;
    }
    public ParamException(List<String> fieldList, List<String> msgList, Exception ex) throws CustomizeException {
        super(generatorMessage(fieldList, msgList), ex);
        this.fieldList = fieldList;
        this.msgList = msgList;
    }
    private static String generatorMessage(List<String> fieldList, List<String> msgList) throws CustomizeException {
        if (CollectionUtils.isEmpty(fieldList) || CollectionUtils.isEmpty(msgList) || fieldList.size() != msgList.size()) {
            return "参数错误";
        }
        StringBuilder message = new StringBuilder();
        for (int i = 0; i < fieldList.size(); i++) {
            String field = fieldList.get(i);
            String msg = msgList.get(i);
            if (i == fieldList.size() - 1) {
                message.append(field).append(":").append(msg);
            } else {
                message.append(field).append(":").append(msg).append(",");
            }
        }
        return message.toString();
    }
}

自定义异常:

package com.mry.springboottools.validation;

public class CustomizeException extends Exception {
    public CustomizeException(String message, Throwable cause) {
        super(message, cause);
    }
    public CustomizeException(String message) {
        super(message);
    }
}

自定义starter

自定义starter步骤:
1.创建工厂,编写功能代码;
2.声明自动配置类,把需要对外提供的对象创建好,通过配置类统一向外暴露;
3.在resource目录下准备一个名为spring/spring.factories的文件,以org.springframework.boot.autoconfigure.EnableAutoConfiguration为key,自动配置类为value列表,进行注册;

RequestBodyAdvice和ResponseBodyAdvice

1.RequestBodyAdvice是对请求的json串进行处理, 一般使用环境是处理接口参数的自动解密;
2.ResponseBodyAdvice是对请求响应的json传进行处理,一般用于相应结果的加密;

功能介绍

接口数据的时候,返回的是加密之后的数据 接口入参的时候,接收的是解密之后的数据,但是在进入接口之前,加密的会自动解密,取得对应的数据。

功能细节

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

所有的实体类提取一个公共父类,包含属性时间戳,用于加密数据返回之后的实效性,如果超过60分钟,那么其他接口将不进行处理。

如果接口加了加密注解EncryptionAnnotation,并且返回统一的json数据Result类,则自动对数据进行加密。如果是继承了统一父类RequestBase的数据,自动注入时间戳,确保数据的时效性。

如果接口加了解密注解DecryptionAnnotation,并且参数使用RequestBody注解标注,传入json使用统一格式RequestData类,并且内容是继承了包含时间长的父类RequestBase,则自动解密,并且转为对应的数据类型。

功能提供Springboot的starter,实现开箱即用。

代码实现

项目结构

在这里插入图片描述

crypto-common

在这里插入图片描述

crypto-spring-boot-starter 代码结构

在这里插入图片描述

核心代码

crypto.properties AES需要的参数配置

# \u6A21\u5F0F cn.hutool.crypto.Mode
crypto.mode=CTS
# \u8865\u7801\u65B9\u5F0F cn.hutool.crypto.Mode
crypto.padding=PKCS5Padding
# \u79D8\u94A5
crypto.key=testkey123456789
# \u76D0
crypto.iv=testiv1234567890

spring.factories 自动配置文件

org.springframework.boot.autoconfigure.EnableAutoConfiguration=\
com.mry.crypto.config.AppConfig

CryptConfig AES需要的配置参数

package com.mry.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;

@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 自动配置类

package com.mry.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;

@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));
    }
}
package com.mry.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;

@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 请求自动解密

package com.mry.crypto.advice;
import com.fasterxml.jackson.databind.ObjectMapper;
import com.mry.crypto.annotation.DecryptionAnnotation;
import com.mry.crypto.common.exception.ParamException;
import com.mry.crypto.constant.CryptoConstant;
import com.mry.crypto.entity.RequestBase;
import com.mry.crypto.entity.RequestData;
import com.mry.crypto.util.AESUtil;
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 javax.servlet.ServletInputStream;
import javax.servlet.http.HttpServletRequest;
import java.io.IOException;
import java.lang.reflect.Type;

@ControllerAdvice
public class DecryptRequestBodyAdvice implements RequestBodyAdvice {
    @Autowired
    private ObjectMapper objectMapper;
    
    @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;
    }
    
    @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错误");
        }
        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("参数错误");
        }
        // 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);
        // 获取结果
        Object result = objectMapper.readValue(decryptText, body.getClass());
        // 强制所有实体类必须继承RequestBase类,设置时间戳
        if (result instanceof RequestBase) {
            // 获取时间戳
            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("时间戳不合法");
            }
            // 返回解密之后的数据
            return result;
        } else {
            throw new ParamException(String.format("请求参数类型:%s 未继承:%s", result.getClass().getName(), RequestBase.class.getName()));
        }
    }
    
    @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 相应自动加密

package com.mry.crypto.advice;
import com.fasterxml.jackson.databind.ObjectMapper;
import com.mry.crypto.annotation.DecryptionAnnotation;
import com.mry.crypto.common.exception.ParamException;
import com.mry.crypto.constant.CryptoConstant;
import com.mry.crypto.entity.RequestBase;
import com.mry.crypto.entity.RequestData;
import com.mry.crypto.util.AESUtil;
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 javax.servlet.ServletInputStream;
import javax.servlet.http.HttpServletRequest;
import java.io.IOException;
import java.lang.reflect.Type;

@ControllerAdvice
public class DecryptRequestBodyAdvice implements RequestBodyAdvice {
    @Autowired
    private ObjectMapper objectMapper;
    
    @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;
    }
    
    @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错误");
        }
        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("参数错误");
        }
        // 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);
        // 获取结果
        Object result = objectMapper.readValue(decryptText, body.getClass());
        // 强制所有实体类必须继承RequestBase类,设置时间戳
        if (result instanceof RequestBase) {
            // 获取时间戳
            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("时间戳不合法");
            }
            // 返回解密之后的数据
            return result;
        } else {
            throw new ParamException(String.format("请求参数类型:%s 未继承:%s", result.getClass().getName(), RequestBase.class.getName()));
        }
    }
    
    @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();
    }
}

crypto-test 代码结构

在这里插入图片描述

核心代码

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
    time-zone: GMT+8
server:
  port: 9999

Teacher 实体类

package com.mry.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;

@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 = "年龄不合法")
    private Integer age;
    @NotNull(message = "生日不能为空")
    private Date birthday;
}

TestController 测试Controller

package com.mry.crypto.controller;
import com.mry.crypto.annotation.DecryptionAnnotation;
import com.mry.crypto.annotation.EncryptionAnnotation;
import com.mry.crypto.common.entity.Result;
import com.mry.crypto.common.entity.ResultBuilder;
import com.mry.crypto.entity.Teacher;
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;

@RestController
public class TestController implements ResultBuilder {
    
    @PostMapping("/get")
    public ResponseEntity<Result<?>> get(@Validated @RequestBody Teacher teacher) {
        return success(teacher);
    }
    
    @PostMapping("/encrypt")
    @EncryptionAnnotation
    public ResponseEntity<Result<?>> encrypt(@Validated @RequestBody Teacher teacher) {
        return success(teacher);
    }
    
    @PostMapping("/encrypt1")
    @EncryptionAnnotation
    public Result<?> encrypt1(@Validated @RequestBody Teacher teacher) {
        return success(teacher).getBody();
    }
    
    @PostMapping("/decrypt")
    @DecryptionAnnotation
    public ResponseEntity<Result<?>> decrypt(@Validated @RequestBody Teacher teacher) {
        return success(teacher);
    }
}

验证

加密:

在这里插入图片描述

解密:

在这里插入图片描述

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