java接口签名(Signature)实现方案

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前言

　　在为第三方系统提供接口的时候，肯定要考虑接口数据的安全问题，比如数据是否被篡改，数据是否已经过时，数据是否可以重复提交等问题。其中我认为最终要的还是数据是否被篡改。在此分享一下我的关于接口签名的实践方案。如果这种方案不是很好理解，请参考另一篇更简单暴力的方案 java接口签名(Signature)实现方案续 。

签名流程

签名规则

　　1、线下分配appid和appsecret，针对不同的调用方分配不同的appid和appsecret

　　2、加入timestamp（时间戳），10分钟内数据有效

　　3、加入流水号nonce（防止重复提交），至少为10位。针对查询接口，流水号只用于日志落地，便于后期日志核查。针对办理类接口需校验流水号在有效期内的唯一性，以避免重复请求。

　　4、加入signature，所有数据的签名信息。

　　以上红色字段放在请求头中。

签名的生成

　　signature 字段生成规则如下。

　数据部分

　　Path：按照path中的顺序将所有value进行拼接

　　Query：按照key字典序排序，将所有key=value进行拼接

　　Form：按照key字典序排序，将所有key=value进行拼接

　　Body：

　　　　Json: 按照key字典序排序，将所有key=value进行拼接（例如{"a":"a","c":"c","b":{"e":"e"}} => a=ab=e=ec=c）

　　　　String: 整个字符串作为一个拼接

　　如果存在多种数据形式，则按照path、query、form、body的顺序进行再拼接，得到所有数据的拼接值。

　　上述拼接的值记作 Y。

　　请求头部分

　　X=”appid=xxxnonce=xxxtimestamp=xxx”

　　生成签名

　　最终拼接值=XY

　　最后将最终拼接值按照如下方法进行加密得到签名。

　　signature=org.apache.commons.codec.digest.HmacUtils.hmacSha256Hex(app secret, 拼接的值);

签名算法实现

　　指定哪些接口或者哪些实体需要进行签名

import java.lang.annotation.Documented;
import java.lang.annotation.Retention;
import java.lang.annotation.Target;import static java.lang.annotation.ElementType.METHOD;
import static java.lang.annotation.ElementType.TYPE;
import static java.lang.annotation.RetentionPolicy.RUNTIME;@Target({TYPE, METHOD})
@Retention(RUNTIME)
@Documented
public @interface Signature {String ORDER_SORT = "ORDER_SORT";//按照order值排序String ALPHA_SORT = "ALPHA_SORT";//字典序排序boolean resubmit() default true;//允许重复请求String sort() default Signature.ALPHA_SORT;
}

　　指定哪些字段需要进行签名

import java.lang.annotation.Documented;
import java.lang.annotation.Retention;
import java.lang.annotation.Target;import static java.lang.annotation.ElementType.FIELD;
import static java.lang.annotation.RetentionPolicy.RUNTIME;@Target({FIELD})
@Retention(RUNTIME)
@Documented
public @interface SignatureField {//签名顺序int order() default 0;//字段name自定义值String customName() default "";//字段value自定义值String customValue() default "";
}

　　核心算法

/*** 生成所有注有 SignatureField属性 key=value的 拼接*/
public static String toSplice(Object object) {if (Objects.isNull(object)) {return StringUtils.EMPTY;}if (isAnnotated(object.getClass(), Signature.class)) {Signature sg = findAnnotation(object.getClass(), Signature.class);switch (sg.sort()) {case Signature.ALPHA_SORT:return alphaSignature(object);case Signature.ORDER_SORT:return orderSignature(object);default:return alphaSignature(object);}}return toString(object);
}private static String alphaSignature(Object object) {StringBuilder result = new StringBuilder();Map<String, String> map = new TreeMap<>();for (Field field : getAllFields(object.getClass())) {if (field.isAnnotationPresent(SignatureField.class)) {field.setAccessible(true);try {if (isAnnotated(field.getType(), Signature.class)) {if (!Objects.isNull(field.get(object))) {map.put(field.getName(), toSplice(field.get(object)));}} else {SignatureField sgf = field.getAnnotation(SignatureField.class);if (StringUtils.isNotEmpty(sgf.customValue()) || !Objects.isNull(field.get(object))) {map.put(StringUtils.isNotBlank(sgf.customName()) ? sgf.customName() : field.getName(), StringUtils.isNotEmpty(sgf.customValue()) ? sgf.customValue() : toString(field.get(object)));}}} catch (Exception e) {LOGGER.error("签名拼接(alphaSignature)异常", e);}}}for (Iterator<Map.Entry<String, String>> iterator = map.entrySet().iterator(); iterator.hasNext(); ) {Map.Entry<String, String> entry = iterator.next();result.append(entry.getKey()).append("=").append(entry.getValue());if (iterator.hasNext()) {result.append(DELIMETER);}}return result.toString();
}/*** 针对array, collection, simple property, map做处理*/
private static String toString(Object object) {Class<?> type = object.getClass();if (BeanUtils.isSimpleProperty(type)) {return object.toString();}if (type.isArray()) {StringBuilder sb = new StringBuilder();for (int i = 0; i < Array.getLength(object); ++i) {sb.append(toSplice(Array.get(object, i)));}return sb.toString();}if (ClassUtils.isAssignable(Collection.class, type)) {StringBuilder sb = new StringBuilder();for (Iterator<?> iterator = ((Collection<?>) object).iterator(); iterator.hasNext(); ) {sb.append(toSplice(iterator.next()));if (iterator.hasNext()) {sb.append(DELIMETER);}}return sb.toString();}if (ClassUtils.isAssignable(Map.class, type)) {StringBuilder sb = new StringBuilder();for (Iterator<? extends Map.Entry<String, ?>> iterator = ((Map<String, ?>) object).entrySet().iterator(); iterator.hasNext(); ) {Map.Entry<String, ?> entry = iterator.next();if (Objects.isNull(entry.getValue())) {continue;}sb.append(entry.getKey()).append("=").append(toSplice(entry.getValue()));if (iterator.hasNext()) {sb.append(DELIMETER);}}return sb.toString();}return NOT_FOUND;
}

签名的校验

　　header中的参数如下

　　签名实体

import com.google.common.base.MoreObjects;
import com.google.common.collect.Sets;
import org.hibernate.validator.constraints.NotBlank;import java.util.Set;@ConfigurationProperties(prefix = "wmhopenapi.validate", exceptionIfInvalid = false)
@Signature
public class SignatureHeaders {public static final String SIGNATURE_HEADERS_PREFIX = "wmhopenapi-validate";public static final Set<String> HEADER_NAME_SET = Sets.newHashSet();private static final String HEADER_APPID = SIGNATURE_HEADERS_PREFIX + "-appid";private static final String HEADER_TIMESTAMP = SIGNATURE_HEADERS_PREFIX + "-timestamp";private static final String HEADER_NONCE = SIGNATURE_HEADERS_PREFIX + "-nonce";private static final String HEADER_SIGNATURE = SIGNATURE_HEADERS_PREFIX + "-signature";static {HEADER_NAME_SET.add(HEADER_APPID);HEADER_NAME_SET.add(HEADER_TIMESTAMP);HEADER_NAME_SET.add(HEADER_NONCE);HEADER_NAME_SET.add(HEADER_SIGNATURE);}/*** 线下分配的值* 客户端和服务端各自保存appId对应的appSecret*/@NotBlank(message = "Header中缺少" + HEADER_APPID)@SignatureFieldprivate String appid;/*** 线下分配的值* 客户端和服务端各自保存，与appId对应*/@SignatureFieldprivate String appsecret;/*** 时间戳，单位: ms*/@NotBlank(message = "Header中缺少" + HEADER_TIMESTAMP)@SignatureFieldprivate String timestamp;/*** 流水号【防止重复提交】; (备注：针对查询接口，流水号只用于日志落地，便于后期日志核查； 针对办理类接口需校验流水号在有效期内的唯一性，以避免重复请求)*/@NotBlank(message = "Header中缺少" + HEADER_NONCE)@SignatureFieldprivate String nonce;/*** 签名*/@NotBlank(message = "Header中缺少" + HEADER_SIGNATURE)private String signature;public String getAppid() {return appid;}public void setAppid(String appid) {this.appid = appid;}public String getAppsecret() {return appsecret;}public void setAppsecret(String appsecret) {this.appsecret = appsecret;}public String getTimestamp() {return timestamp;}public void setTimestamp(String timestamp) {this.timestamp = timestamp;}public String getNonce() {return nonce;}public void setNonce(String nonce) {this.nonce = nonce;}public String getSignature() {return signature;}public void setSignature(String signature) {this.signature = signature;}@Overridepublic String toString() {return MoreObjects.toStringHelper(this).add("appid", appid).add("appsecret", appsecret).add("timestamp", timestamp).add("nonce", nonce).add("signature", signature).toString();}
}

　　根据request 中 header值生成SignatureHeaders实体

private SignatureHeaders generateSignatureHeaders(Signature signature, HttpServletRequest request) throws Exception {//NOSONARMap<String, Object> headerMap = Collections.list(request.getHeaderNames()).stream().filter(headerName -> SignatureHeaders.HEADER_NAME_SET.contains(headerName)).collect(Collectors.toMap(headerName -> headerName.replaceAll("-", "."), headerName -> request.getHeader(headerName)));PropertySource propertySource = new MapPropertySource("signatureHeaders", headerMap);SignatureHeaders signatureHeaders = RelaxedConfigurationBinder.with(SignatureHeaders.class).setPropertySources(propertySource).doBind();Optional<String> result = ValidatorUtils.validateResultProcess(signatureHeaders);if (result.isPresent()) {throw new ServiceException("WMH5000", result.get());}
    //从配置中拿到appid对应的appsecretString appSecret = limitConstants.getSignatureLimit().get(signatureHeaders.getAppid());if (StringUtils.isBlank(appSecret)) {LOGGER.error("未找到appId对应的appSecret, appId=" + signatureHeaders.getAppid());throw new ServiceException("WMH5002");}//其他合法性校验Long now = System.currentTimeMillis();Long requestTimestamp = Long.parseLong(signatureHeaders.getTimestamp());if ((now - requestTimestamp) > EXPIRE_TIME) {String errMsg = "请求时间超过规定范围时间10分钟, signature=" + signatureHeaders.getSignature();LOGGER.error(errMsg);throw new ServiceException("WMH5000", errMsg);}String nonce = signatureHeaders.getNonce();if (nonce.length() < 10) {String errMsg = "随机串nonce长度最少为10位, nonce=" + nonce;LOGGER.error(errMsg);throw new ServiceException("WMH5000", errMsg);}if (!signature.resubmit()) {String existNonce = redisCacheService.getString(nonce);if (StringUtils.isBlank(existNonce)) {redisCacheService.setString(nonce, nonce);redisCacheService.expire(nonce, (int) TimeUnit.MILLISECONDS.toSeconds(RESUBMIT_DURATION));} else {String errMsg = "不允许重复请求, nonce=" + nonce;LOGGER.error(errMsg);throw new ServiceException("WMH5000", errMsg);}}//设置appsecretsignatureHeaders.setAppsecret(appSecret);return signatureHeaders;
}

　　生成签名前需要几个步骤，如下。

　　　　（1）、appid是否合法

　　　　（2）、根据appid从配置中心中拿到appsecret

　　　　（3）、请求是否已经过时，默认10分钟

　　　　（4）、随机串是否合法

　　　　（5）、是否允许重复请求

　　生成header信息参数拼接

String headersToSplice = SignatureUtils.toSplice(signatureHeaders);

　　生成header中的参数，mehtod中的参数的拼接

private List<String> generateAllSplice(Method method, Object[] args, String headersToSplice) {List<String> pathVariables = Lists.newArrayList(), requestParams = Lists.newArrayList();String beanParams = StringUtils.EMPTY;for (int i = 0; i < method.getParameterCount(); ++i) {MethodParameter mp = new MethodParameter(method, i);boolean findSignature = false;for (Annotation anno : mp.getParameterAnnotations()) {if (anno instanceof PathVariable) {if (!Objects.isNull(args[i])) {pathVariables.add(args[i].toString());}findSignature = true;} else if (anno instanceof RequestParam) {RequestParam rp = (RequestParam) anno;String name = mp.getParameterName();if (StringUtils.isNotBlank(rp.name())) {name = rp.name();}if (!Objects.isNull(args[i])) {List<String> values = Lists.newArrayList();if (args[i].getClass().isArray()) {//数组for (int j = 0; j < Array.getLength(args[i]); ++j) {values.add(Array.get(args[i], j).toString());}} else if (ClassUtils.isAssignable(Collection.class, args[i].getClass())) {//集合for (Object o : (Collection<?>) args[i]) {values.add(o.toString());}} else {//单个值
                        values.add(args[i].toString());}values.sort(Comparator.naturalOrder());requestParams.add(name + "=" + StringUtils.join(values));}findSignature = true;} else if (anno instanceof RequestBody || anno instanceof ModelAttribute) {beanParams = SignatureUtils.toSplice(args[i]);findSignature = true;}if (findSignature) {break;}}if (!findSignature) {LOGGER.info(String.format("签名未识别的注解, method=%s, parameter=%s, annotations=%s", method.getName(), mp.getParameterName(), StringUtils.join(mp.getMethodAnnotations())));}}List<String> toSplices = Lists.newArrayList();toSplices.add(headersToSplice);toSplices.addAll(pathVariables);requestParams.sort(Comparator.naturalOrder());toSplices.addAll(requestParams);toSplices.add(beanParams);return toSplices;
}

　　对最终的拼接结果重新生成签名信息

SignatureUtils.signature(allSplice.toArray(new String[]{}), signatureHeaders.getAppsecret());

依赖第三方工具包

<dependency><groupId>org.apache.commons</groupId><artifactId>commons-lang3</artifactId>
</dependency>
<dependency><groupId>org.springframework</groupId><artifactId>spring-beans</artifactId>
</dependency>

使用示例

　　生成签名

//初始化请求头信息
SignatureHeaders signatureHeaders = new SignatureHeaders();
signatureHeaders.setAppid("111");
signatureHeaders.setAppsecret("222");
signatureHeaders.setNonce(SignatureUtils.generateNonce());
signatureHeaders.setTimestamp(String.valueOf(System.currentTimeMillis()));
List<String> pathParams = new ArrayList<>();
//初始化path中的数据
pathParams.add(SignatureUtils.encode("18237172801", signatureHeaders.getAppsecret()));
//调用签名工具生成签名
signatureHeaders.setSignature(SignatureUtils.signature(signatureHeaders, pathParams, null, null));
System.out.println("签名数据: " + signatureHeaders);
System.out.println("请求数据: " + pathParams);

　　输出结果

拼接结果: appid=111^_^appsecret=222^_^nonce=c9e778ba668c8f6fedf35634eb493af6304d54392d990262d9e7c1960b475b67^_^timestamp=1538207443910^_^w8rAwcXDxcDKwsM=^_^
签名数据: SignatureHeaders{appid=111, appsecret=222, timestamp=1538207443910, nonce=c9e778ba668c8f6fedf35634eb493af6304d54392d990262d9e7c1960b475b67, signature=0a7d0b5e802eb5e52ac0cfcd6311b0faba6e2503a9a8d1e2364b38617877574d}
请求数据: [w8rAwcXDxcDKwsM=]