今天聊下接口安全问题，涉及到接口的加密和解密
经常和外部单位接口调用梳理了相关技术方案，主要的需求点如下：
1，尽量少改动，不影响之前的业务逻辑
2，考虑到时间紧迫性，可采用对称性加密方式，服务需要对接安卓，IOS，H5三端，另外考虑到H5端存储密钥安全性相对来说比较低一些，故针对H5和安卓，IOS分配两套密钥
3，要兼容低版本的接口，后面新开发的接口可不兼容
4，接口有GET和POST两种接口，需要都进行加密。
需求分析：
1，服务端，客户端和H5统一拦截加密，网上有成熟的方案，也可以按其他服务中实现的加密流程来实现
2，使用AES放松加密，考虑到H5端存储密钥安全性相对来水比较低一些。故针对H5和安卓，IOS分配两套密钥
3，本次涉及客户端和服务器端的整体改造，经讨论，新接口统一加/secret/ 前缀来区分
用户类：
@Data
public class User {private Integer id;private String name;private UserType userType = UserType.COMMON;@JsonFormat(pattern = "yyyy-MM-dd HH:mm:ss")private LocalDateTime registerTime;
}用户类型枚举类
@Getter
@JsonFormat(shape = JsonFormat.Shape.OBJECT)
public enum UserType {VIP("VIP用户"),COMMON("普通用户");private String code;private String type;UserType(String type) {this.code = name();this.type = type;}
}简单的用户列表查询示例：
@RestController
@RequestMapping(value = {"/user", "/secret/user"})
public class UserController {@RequestMapping("/list")ResponseEntity<List<User>> listUser() {List<User> users = new ArrayList<>();User u = new User();u.setId(1);u.setName("boyka");u.setRegisterTime(LocalDateTime.now());u.setUserType(UserType.COMMON);users.add(u);ResponseEntity<List<User>> response = new ResponseEntity<>();response.setCode(200);response.setData(users);response.setMsg("用户列表查询成功");return response;}
}调用：localhost:8080/user/list
运行如下
{"code": 200,"data": [{"id": 1,"name": "boyka","userType": {"code": "COMMON","type": "普通用户"},"registerTime": "2022-03-24 23:58:39"}],"msg": "用户列表查询成功"
}目前主要是利用ControllerAdvice来对请求和响应体进行拦截，主要定义SecretRequestAdvice对请求进行加密和SecretResponseAdvice对响应进行加密(实际情况会稍微复杂一点，项目中又GET类型请求，自定义了一个Filter进行不同的请求解密处理)。
好了，网上的ControllerAdvice使用示例非常多，我这把两个核心方法给大家展示看看，相信大佬们一看就晓得了
SecretRequestAdvice请求解密
@ControllerAdvice
@Order(Ordered.HIGHEST_PRECEDENCE)
@Slf4j
public class SecretRequestAdvice extends RequestBodyAdviceAdapter {@Overridepublic boolean supports(MethodParameter methodParameter, Type type, Class<? extends HttpMessageConverter<?>> aClass) {return true;}@Overridepublic HttpInputMessage beforeBodyRead(HttpInputMessage inputMessage, MethodParameter parameter, Type targetType, Class<? extends HttpMessageConverter<?>> converterType) throws IOException {//如果支持加密消息，进行消息解密。String httpBody;if (Boolean.TRUE.equals(SecretFilter.secretThreadLocal.get())) {httpBody = decryptBody(inputMessage);} else {httpBody = StreamUtils.copyToString(inputMessage.getBody(), Charset.defaultCharset());}//返回处理后的消息体给messageConvertreturn new SecretHttpMessage(new ByteArrayInputStream(httpBody.getBytes()), inputMessage.getHeaders());}/*** 解密消息体** @param inputMessage 消息体* @return 明文*/private String decryptBody(HttpInputMessage inputMessage) throws IOException {InputStream encryptStream = inputMessage.getBody();String requestBody = StreamUtils.copyToString(encryptStream, Charset.defaultCharset());// 验签过程HttpHeaders headers = inputMessage.getHeaders();if (CollectionUtils.isEmpty(headers.get("clientType"))|| CollectionUtils.isEmpty(headers.get("timestamp"))|| CollectionUtils.isEmpty(headers.get("salt"))|| CollectionUtils.isEmpty(headers.get("signature"))) {throw new ResultException(SECRET_API_ERROR, "请求解密参数错误，clientType、timestamp、salt、signature等参数传递是否正确传递");}String timestamp = String.valueOf(Objects.requireNonNull(headers.get("timestamp")).get(0));String salt = String.valueOf(Objects.requireNonNull(headers.get("salt")).get(0));String signature = String.valueOf(Objects.requireNonNull(headers.get("signature")).get(0));String privateKey = SecretFilter.clientPrivateKeyThreadLocal.get();ReqSecret reqSecret = JSON.parseObject(requestBody, ReqSecret.class);String data = reqSecret.getData();String newSignature = "";if (!StringUtils.isEmpty(privateKey)) {newSignature = Md5Utils.genSignature(timestamp + salt + data + privateKey);}if (!newSignature.equals(signature)) {// 验签失败throw new ResultException(SECRET_API_ERROR, "验签失败，请确认加密方式是否正确");}try {String decrypt = EncryptUtils.aesDecrypt(data, privateKey);if (StringUtils.isEmpty(decrypt)) {decrypt = "{}";}return decrypt;} catch (Exception e) {log.error("error: ", e);}throw new ResultException(SECRET_API_ERROR, "解密失败");}
}SecretResponseAdvice响应加密
@ControllerAdvice
public class SecretResponseAdvice implements ResponseBodyAdvice {private Logger logger = LoggerFactory.getLogger(SecretResponseAdvice.class);@Overridepublic boolean supports(MethodParameter methodParameter, Class aClass) {return true;}@Overridepublic Object beforeBodyWrite(Object o, MethodParameter methodParameter, MediaType mediaType, Class aClass, ServerHttpRequest serverHttpRequest, ServerHttpResponse serverHttpResponse) {// 判断是否需要加密Boolean respSecret = SecretFilter.secretThreadLocal.get();String secretKey = SecretFilter.clientPrivateKeyThreadLocal.get();// 清理本地缓存SecretFilter.secretThreadLocal.remove();SecretFilter.clientPrivateKeyThreadLocal.remove();if (null != respSecret && respSecret) {if (o instanceof ResponseBasic) {// 外层加密级异常if (SECRET_API_ERROR == ((ResponseBasic) o).getCode()) {return SecretResponseBasic.fail(((ResponseBasic) o).getCode(), ((ResponseBasic) o).getData(), ((ResponseBasic) o).getMsg());}// 业务逻辑try {String data = EncryptUtils.aesEncrypt(JSON.toJSONString(o), secretKey);// 增加签名long timestamp = System.currentTimeMillis() / 1000;int salt = EncryptUtils.genSalt();String dataNew = timestamp + "" + salt + "" + data + secretKey;String newSignature = Md5Utils.genSignature(dataNew);return SecretResponseBasic.success(data, timestamp, salt, newSignature);} catch (Exception e) {logger.error("beforeBodyWrite error:", e);return SecretResponseBasic.fail(SECRET_API_ERROR, "", "服务端处理结果数据异常");}}}return o;}
}运行如下：
请求方法：
localhost:8080/secret/user/listheader:
Content-Type:application/json
signature:55efb04a83ca083dd1e6003cde127c45
timestamp:1648308048
salt:123456
clientType:ANDORIDbody体:
// 原始请求体
{"page": 1,"size": 10
}
// 加密后的请求体
{"data": "1ZBecdnDuMocxAiW9UtBrJzlvVbueP9K0MsIxQccmU3OPG92oRinVm0GxBwdlXXJ"
}// 加密响应体：
{"data": "fxHYvnIE54eAXDbErdrDryEsIYNvsOOkyEKYB1iBcre/QU1wMowHE2BNX/je6OP3NlsCtAeDqcp7J1N332el8q2FokixLvdxAPyW5Un9JiT0LQ3MB8p+nN23pTSIvh9VS92lCA8KULWg2nViSFL5X1VwKrF0K/dcVVZnpw5h227UywP6ezSHjHdA+Q0eKZFGTEv3IzNXWqq/otx5fl1gKQ==","code": 200,"signature": "aa61f19da0eb5d99f13c145a40a7746b","msg": "","timestamp": 1648480034,"salt": 632648
}// 解密后的响应体：
{"code": 200,"data": [{"id": 1,"name": "boyka","registerTime": "2022-03-27T00:19:43.699","userType": "COMMON"}],"msg": "用户列表查询成功","salt": 0
}OK，客户端请求加密-》发起请求-》服务端解密-》业务处理-》服务端响应加密-》客户端解密展示，看起来没啥问题，实际是头天下午花了2小时碰需求，差不多花1小时写好demo测试，然后对所有接口统一进行了处理，整体一下午赶脚应该行了吧，告诉H5和安卓端同学明儿上午联调（不小的大家到这个时候发现猫腻没有，当时确实疏忽了，翻了大车......）
次日，安卓端反馈，你这个加解密有问题，解密后的数据格式和之前不一样，仔细一看，擦，这个userType和registerTime是不对劲，开始思考：这个能是哪儿的问题呢？1s之后，初步定位，应该是响应体的JSON.toJSONString的问题：
String data = EncryptUtils.aesEncrypt(JSON.toJSONString(o)),
Debug断点调试，果然，是JSON.toJSONString(o)这一步骤转换出了问题，那JSON转换时是不是有高级属性可以配置生成想要的序列化格式呢？FastJson在序列化时提供重载方法，找到其中一个"SerializerFeature"参数可以琢磨一下，这个参数是可以对序列化进行配置的，它提供了很多配置类型，其中感觉这几个比较沾边
WriteEnumUsingToString,
WriteEnumUsingName,
UseISO8601DateFormat
对枚举类型来说，默认是使用的WriteEnumUsingName(枚举的Name)， 另一种WriteEnumUsingToString是重新toString方法，理论上可以转换成想要的样子，即这个样子
@Getter
@JsonFormat(shape = JsonFormat.Shape.OBJECT)
public enum UserType {VIP("VIP用户"),COMMON("普通用户");private String code;private String type;UserType(String type) {this.code = name();this.type = type;}@Overridepublic String toString() {return "{" +"\"code\":\"" + name() + '\"' +", \"type\":\"" + type + '\"' +'}';}
}结果转换出来的数据是字符串类型"{"code":"COMMON", "type":"普通用户"}"，这个方法好像行不通，还有什么好办法呢？思前想后，看文章开始定义的User和UserType类，标记数据序列化格式@JsonFormat，再突然想起之前看到过的一些文章，SpringMVC底层默认是使用Jackson进行序列化的，那好了，就用Jacksong实施呗，将SecretResponseAdvice中的序列化方法替换一下
String data = EncryptUtils.aesEncrypt(JSON.toJSONString(o), secretKey);换为：
String data =EncryptUtils.aesEncrypt(new ObjectMapper().writeValueAsString(o), secretKey);运行结果如下：
{"code": 200,"data": [{"id": 1,"name": "boyka","userType": {"code": "COMMON","type": "普通用户"},"registerTime": {"month": "MARCH","year": 2022,"dayOfMonth": 29,"dayOfWeek": "TUESDAY","dayOfYear": 88,"monthValue": 3,"hour": 22,"minute": 30,"nano": 453000000,"second": 36,"chronology": {"id": "ISO","calendarType": "iso8601"}}}],"msg": "用户列表查询成功"
}解密后的userType枚举类型和非加密版本一样了，舒服了，== 好像还不对，registerTime怎么变成这个样子了？原本是"2022-03-24 23:58:39"这种格式的，网上有很多解决方案，不过用在我们目前这个需求里面，就是有损改装了啊，不太可取，遂去Jackson官网上查找一下相关文档，当然Jackson也提供了ObjectMapper的序列化配置，重新再初始化配置ObjectMpper对象
String DATE_TIME_FORMATTER = "yyyy-MM-dd HH:mm:ss";
ObjectMapper objectMapper = new Jackson2ObjectMapperBuilder().findModulesViaServiceLoader(true).serializerByType(LocalDateTime.class, new LocalDateTimeSerializer(DateTimeFormatter.ofPattern(DATE_TIME_FORMATTER))).deserializerByType(LocalDateTime.class, new LocalDateTimeDeserializer(DateTimeFormatter.ofPattern(DATE_TIME_FORMATTER))).build();转化结果：
{"code": 200,"data": [{"id": 1,"name": "boyka","userType": {"code": "COMMON","type": "普通用户"},"registerTime": "2022-03-29 22:57:33"}],"msg": "用户列表查询成功"
}OK，和非加密版的终于一致了，完了吗？感觉还是可能存在些什么问题，首先业务代码的时间序列化需求不一样，有"yyyy-MM-dd hh:mm:ss"的，也有"yyyy-MM-dd"的，还可能其他配置思考不到位的，导致和之前非加密版返回数据不一致的问题，到时候联调测出来了也麻烦，有没有一劳永逸的办法呢？哎，这个时候如果你看过 Spring 源码的话，就应该知道spring框架自身是怎么序列化的，照着配置应该就行嘛，好像有点道理，我这里不从0开始分析源码了
跟着执行链路，找到具体的响应序列化，重点就是RequestResponseBodyMethodProcessor
protected <T> void writeWithMessageConverters(@Nullable T value, MethodParameter returnType, ServletServerHttpRequest inputMessage, ServletServerHttpResponse outputMessage) throws IOException, HttpMediaTypeNotAcceptableException, HttpMessageNotWritableException {// 获取响应的拦截器链并执行beforeBodyWrite方法，也就是执行了我们自定义的SecretResponseAdvice中的beforeBodyWrite啦body = this.getAdvice().beforeBodyWrite(body, returnType, selectedMediaType, converter.getClass(), inputMessage, outputMessage);if (body != null) {// 执行响应体序列化工作if (genericConverter != null) {genericConverter.write(body, (Type)targetType, selectedMediaType, outputMessage);} else {converter.write(body, selectedMediaType, outputMessage);}}进而通过实例化的AbstractJackson2HttpMessageConverter对象找到执行序列化的核心方法
-> AbstractGenericHttpMessageConverter:public final void write(T t, @Nullable Type type, @Nullable MediaType contentType, HttpOutputMessage outputMessage) throws IOException, HttpMessageNotWritableException {...this.writeInternal(t, type, outputMessage);outputMessage.getBody().flush();}-> 找到Jackson序列化 AbstractJackson2HttpMessageConverter:// 从spring容器中获取并设置的ObjectMapper实例protected ObjectMapper objectMapper;protected void writeInternal(Object object, @Nullable Type type, HttpOutputMessage outputMessage) throws IOException, HttpMessageNotWritableException {MediaType contentType = outputMessage.getHeaders().getContentType();JsonEncoding encoding = this.getJsonEncoding(contentType);JsonGenerator generator = this.objectMapper.getFactory().createGenerator(outputMessage.getBody(), encoding);this.writePrefix(generator, object);Object value = object;Class<?> serializationView = null;FilterProvider filters = null;JavaType javaType = null;if (object instanceof MappingJacksonValue) {MappingJacksonValue container = (MappingJacksonValue)object;value = container.getValue();serializationView = container.getSerializationView();filters = container.getFilters();}if (type != null && TypeUtils.isAssignable(type, value.getClass())) {javaType = this.getJavaType(type, (Class)null);}ObjectWriter objectWriter = serializationView != null ? this.objectMapper.writerWithView(serializationView) : this.objectMapper.writer();if (filters != null) {objectWriter = objectWriter.with(filters);}if (javaType != null && javaType.isContainerType()) {objectWriter = objectWriter.forType(javaType);}SerializationConfig config = objectWriter.getConfig();if (contentType != null && contentType.isCompatibleWith(MediaType.TEXT_EVENT_STREAM) && config.isEnabled(SerializationFeature.INDENT_OUTPUT)) {objectWriter = objectWriter.with(this.ssePrettyPrinter);}// 重点进行序列化objectWriter.writeValue(generator, value);this.writeSuffix(generator, object);generator.flush();}看出SpringMVC在进行响应序列化的时候是从容器中获取的ObjectMapper实例对象，并会根据不同的默认配置条件进行序列化，那处理方法就简单了，我也可以从Spring容器拿数据进行序列化啊。SecretResponseAdvice进行如下进一步改造
@ControllerAdvice
public class SecretResponseAdvice implements ResponseBodyAdvice {@Autowiredprivate ObjectMapper objectMapper;@Overridepublic Object beforeBodyWrite(....) {.....String dataStr =objectMapper.writeValueAsString(o);String data = EncryptUtils.aesEncrypt(dataStr, secretKey);.....}}