API接口設(shè)計(jì)之token、timestamp、sign 具體設(shè)計(jì)與實(shí)現(xiàn)

• API Token(接口令牌): 用于訪問不需要用戶登錄的接口，如登錄、注冊(cè)、一些基本數(shù)據(jù)的獲取等。

  獲取接口令牌需要拿appId、timestamp和sign來換，sign=加密(timestamp+key)

• USER Token(用戶令牌): 用于訪問需要用戶登錄之后的接口，如：

  獲取我的基本信息、保存、修改、刪除等操作。

  獲取用戶令牌需要拿用戶名和密碼來換

• Pingflood: 該攻擊在短時(shí)間內(nèi)向目的主機(jī)發(fā)送大量ping包，造成網(wǎng)絡(luò)堵塞或主機(jī)資源耗盡。

• Synflood: 該攻擊以多個(gè)隨機(jī)的源主機(jī)地址向目的主機(jī)發(fā)送SYN包，而在收到目的主機(jī)的SYN ACK后并不回應(yīng)，這樣，目的主機(jī)就為這些源主機(jī)建立了大量的連接隊(duì)列，而且由于沒有收到ACK一直維護(hù)著這

• Smurf：

  該攻擊向一個(gè)子網(wǎng)的廣播地址發(fā)一個(gè)帶有特定請(qǐng)求（如ICMP回應(yīng)請(qǐng)求）的包，并且將源地址偽裝成想要攻擊的主機(jī)地址。

  子網(wǎng)上所有主機(jī)都回應(yīng)廣播包請(qǐng)求而向被攻擊主機(jī)發(fā)包，使該主機(jī)受到攻擊。

• Land-based：

  攻擊者將一個(gè)包的源地址和目的地址都設(shè)置為目標(biāo)主機(jī)的地址，然后將該包通過IP欺騙的方式發(fā)送給被攻擊主機(jī)，這種包可以造成被攻擊主機(jī)因試圖與自己建立連接而陷入死循環(huán)，從而很大程度地降低了系統(tǒng)性能。

• Ping of Death：

  根據(jù)TCP/IP的規(guī)范，一個(gè)包的長度最大為65536字節(jié)。

  盡管一個(gè)包的長度不能超過65536字節(jié)，但是一個(gè)包分成的多個(gè)片段的疊加卻能做到。

  當(dāng)一個(gè)主機(jī)收到了長度大于65536字節(jié)的包時(shí)，就是受到了Ping of Death攻擊，該攻擊會(huì)造成主機(jī)的宕機(jī)。

• Teardrop：

  IP數(shù)據(jù)包在網(wǎng)絡(luò)傳遞時(shí)，數(shù)據(jù)包可以分成更小的片段。

  攻擊者可以通過發(fā)送兩段（或者更多）數(shù)據(jù)包來實(shí)現(xiàn)TearDrop攻擊。

  第一個(gè)包的偏移量為0，長度為N，第二個(gè)包的偏移量小于N。

  為了合并這些數(shù)據(jù)段，TCP/IP堆棧會(huì)分配超乎尋常的巨大資源，從而造成系統(tǒng)資源的缺乏甚至機(jī)器的重新啟動(dòng)。

• PingSweep：

  使用ICMP Echo輪詢多個(gè)主機(jī)。

1. 接口調(diào)用方(客戶端)向接口提供方(服務(wù)器)申請(qǐng)接口調(diào)用賬號(hào)，申請(qǐng)成功后，接口提供方會(huì)給接口調(diào)用方一個(gè)appId和一個(gè)key參數(shù)

2. 客戶端攜帶參數(shù)appId、timestamp、sign去調(diào)用服務(wù)器端的API token，其中sign=加密(appId + timestamp + key)

3. 客戶端拿著api_token 去訪問不需要登錄就能訪問的接口

4. 當(dāng)訪問用戶需要登錄的接口時(shí)，客戶端跳轉(zhuǎn)到登錄頁面，通過用戶名和密碼調(diào)用登錄接口，登錄接口會(huì)返回一個(gè)usertoken, 客戶端拿著usertoken 去訪問需要登錄才能訪問的接口

<dependency>
    <groupId>org.springframework.boot</groupId>
    <artifactId>spring-boot-starter-data-redis</artifactId>
</dependency>
<dependency>
    <groupId>redis.clients</groupId>
    <artifactId>jedis</artifactId>
    <version>2.9.0</version>
</dependency>

<dependency>
    <groupId>org.springframework.boot</groupId>
    <artifactId>spring-boot-starter-web</artifactId>
</dependency>

@Configuration
public class RedisConfiguration {
    @Bean
    public JedisConnectionFactory jedisConnectionFactory(){
        return new JedisConnectionFactory();
    }

    /**
     * 支持存儲(chǔ)對(duì)象
     * @return
     */
    @Bean
    public RedisTemplate<String, String> redisTemplate(){
        RedisTemplate<String, String> redisTemplate = new StringRedisTemplate();
        redisTemplate.setConnectionFactory(jedisConnectionFactory());
        Jackson2JsonRedisSerializer jackson2JsonRedisSerializer = new Jackson2JsonRedisSerializer(Object.class);
        ObjectMapper objectMapper = new ObjectMapper();
        objectMapper.setVisibility(PropertyAccessor.ALL, JsonAutoDetect.Visibility.ANY);
        objectMapper.enableDefaultTyping(ObjectMapper.DefaultTyping.NON_FINAL);

        jackson2JsonRedisSerializer.setObjectMapper(objectMapper);
        redisTemplate.setValueSerializer(jackson2JsonRedisSerializer);
        redisTemplate.afterPropertiesSet();

        return redisTemplate;
    }
}

@Slf4j
@RestController
@RequestMapping("/api/token")
public class TokenController {

    @Autowired
    private RedisTemplate redisTemplate;

    /**
     * API Token
     *
     * @param sign
     * @return
     */
    @PostMapping("/api_token")
    public ApiResponse<AccessToken> apiToken(String appId, @RequestHeader("timestamp") String timestamp, @RequestHeader("sign") String sign) {
        Assert.isTrue(!StringUtils.isEmpty(appId) && !StringUtils.isEmpty(timestamp) && !StringUtils.isEmpty(sign), "參數(shù)錯(cuò)誤");

        long reqeustInterval = System.currentTimeMillis() - Long.valueOf(timestamp);
        Assert.isTrue(reqeustInterval < 5 * 60 * 1000, "請(qǐng)求過期，請(qǐng)重新請(qǐng)求");

        // 1. 根據(jù)appId查詢數(shù)據(jù)庫獲取appSecret
        AppInfo appInfo = new AppInfo("1", "12345678954556");

        // 2. 校驗(yàn)簽名
        String signString = timestamp + appId + appInfo.getKey();
        String signature = MD5Util.encode(signString);
        log.info(signature);
        Assert.isTrue(signature.equals(sign), "簽名錯(cuò)誤");

        // 3. 如果正確生成一個(gè)token保存到redis中，如果錯(cuò)誤返回錯(cuò)誤信息
        AccessToken accessToken = this.saveToken(0, appInfo, null);

        return ApiResponse.success(accessToken);
    }


    @NotRepeatSubmit(5000)
    @PostMapping("user_token")
    public ApiResponse<UserInfo> userToken(String username, String password) {
        // 根據(jù)用戶名查詢密碼, 并比較密碼(密碼可以RSA加密一下)
        UserInfo userInfo = new UserInfo(username, "81255cb0dca1a5f304328a70ac85dcbd", "111111");
        String pwd = password + userInfo.getSalt();
        String passwordMD5 = MD5Util.encode(pwd);
        Assert.isTrue(passwordMD5.equals(userInfo.getPassword()), "密碼錯(cuò)誤");

        // 2. 保存Token
        AppInfo appInfo = new AppInfo("1", "12345678954556");
        AccessToken accessToken = this.saveToken(1, appInfo, userInfo);
        userInfo.setAccessToken(accessToken);
        return ApiResponse.success(userInfo);
    }

    private AccessToken saveToken(int tokenType, AppInfo appInfo, UserInfo userInfo) {
        String token = UUID.randomUUID().toString();

        // token有效期為2小時(shí)
        Calendar calendar = Calendar.getInstance();
        calendar.setTime(new Date());
        calendar.add(Calendar.SECOND, 7200);
        Date expireTime = calendar.getTime();

        // 4. 保存token
        ValueOperations<String, TokenInfo> operations = redisTemplate.opsForValue();
        TokenInfo tokenInfo = new TokenInfo();
        tokenInfo.setTokenType(tokenType);
        tokenInfo.setAppInfo(appInfo);

        if (tokenType == 1) {
            tokenInfo.setUserInfo(userInfo);
        }

        operations.set(token, tokenInfo, 7200, TimeUnit.SECONDS);

        AccessToken accessToken = new AccessToken(token, expireTime);

        return accessToken;
    }

    public static void main(String[] args) {
        long timestamp = System.currentTimeMillis();
        System.out.println(timestamp);
        String signString = timestamp + "1" + "12345678954556";
        String sign = MD5Util.encode(signString);
        System.out.println(sign);

        System.out.println("-------------------");
        signString = "password=123456&username=1&12345678954556" + "ff03e64b-427b-45a7-b78b-47d9e8597d3b1529815393153sdfsdfsfs" + timestamp + "A1scr6";
        sign = MD5Util.encode(signString);
        System.out.println(sign);
    }
}

@Configuration
public class WebMvcConfiguration extends WebMvcConfigurationSupport {

    private static final String[] excludePathPatterns = {"/api/token/api_token"};

    @Autowired
    private TokenInterceptor tokenInterceptor;

    @Override
    public void addInterceptors(InterceptorRegistry registry) {
        super.addInterceptors(registry);
        registry.addInterceptor(tokenInterceptor)
                .addPathPatterns("/api/**")
                .excludePathPatterns(excludePathPatterns);
    }
}

@Component
public class TokenInterceptor extends HandlerInterceptorAdapter {

    @Autowired
    private RedisTemplate redisTemplate;

    /**
     *
     * @param request
     * @param response
     * @param handler 訪問的目標(biāo)方法
     * @return
     * @throws Exception
     */
    @Override
    public boolean preHandle(HttpServletRequest request, HttpServletResponse response, Object handler) throws Exception {
        String token = request.getHeader("token");
        String timestamp = request.getHeader("timestamp");
        // 隨機(jī)字符串
        String nonce = request.getHeader("nonce");
        String sign = request.getHeader("sign");
        Assert.isTrue(!StringUtils.isEmpty(token) && !StringUtils.isEmpty(timestamp) && !StringUtils.isEmpty(sign), "參數(shù)錯(cuò)誤");

        // 獲取超時(shí)時(shí)間
        NotRepeatSubmit notRepeatSubmit = ApiUtil.getNotRepeatSubmit(handler);
        long expireTime = notRepeatSubmit == null ? 5 * 60 * 1000 : notRepeatSubmit.value();

        // 2. 請(qǐng)求時(shí)間間隔
        long reqeustInterval = System.currentTimeMillis() - Long.valueOf(timestamp);
        Assert.isTrue(reqeustInterval < expireTime, "請(qǐng)求超時(shí)，請(qǐng)重新請(qǐng)求");

        // 3. 校驗(yàn)Token是否存在
        ValueOperations<String, TokenInfo> tokenRedis = redisTemplate.opsForValue();
        TokenInfo tokenInfo = tokenRedis.get(token);
        Assert.notNull(tokenInfo, "token錯(cuò)誤");

        // 4. 校驗(yàn)簽名(將所有的參數(shù)加進(jìn)來，防止別人篡改參數(shù)) 所有參數(shù)看參數(shù)名升續(xù)排序拼接成url
        // 請(qǐng)求參數(shù) + token + timestamp + nonce
        String signString = ApiUtil.concatSignString(request) + tokenInfo.getAppInfo().getKey() + token + timestamp + nonce;
        String signature = MD5Util.encode(signString);
        boolean flag = signature.equals(sign);
        Assert.isTrue(flag, "簽名錯(cuò)誤");

        // 5. 拒絕重復(fù)調(diào)用(第一次訪問時(shí)存儲(chǔ)，過期時(shí)間和請(qǐng)求超時(shí)時(shí)間保持一致), 只有標(biāo)注不允許重復(fù)提交注解的才會(huì)校驗(yàn)
        if (notRepeatSubmit != null) {
            ValueOperations<String, Integer> signRedis = redisTemplate.opsForValue();
            boolean exists = redisTemplate.hasKey(sign);
            Assert.isTrue(!exists, "請(qǐng)勿重復(fù)提交");
            signRedis.set(sign, 0, expireTime, TimeUnit.MILLISECONDS);
        }

        return super.preHandle(request, response, handler);
    }
}

public class MD5Util {

    private static final String hexDigits[] = { "0", "1", "2", "3", "4", "5",
            "6", "7", "8", "9", "a", "b", "c", "d", "e", "f" };

    private static String byteArrayToHexString(byte b[]) {
        StringBuffer resultSb = new StringBuffer();
        for (int i = 0; i < b.length; i++)
            resultSb.append(byteToHexString(b[i]));

        return resultSb.toString();
    }

    private static String byteToHexString(byte b) {
        int n = b;
        if (n < 0)
            n += 256;
        int d1 = n / 16;
        int d2 = n % 16;
        return hexDigits[d1] + hexDigits[d2];
    }

    public static String encode(String origin) {
        return encode(origin, "UTF-8");
    }
    public static String encode(String origin, String charsetname) {
        String resultString = null;
        try {
            resultString = new String(origin);
            MessageDigest md = MessageDigest.getInstance("MD5");
            if (charsetname == null || "".equals(charsetname))
                resultString = byteArrayToHexString(md.digest(resultString
                        .getBytes()));
            else
                resultString = byteArrayToHexString(md.digest(resultString
                        .getBytes(charsetname)));
        } catch (Exception exception) {
        }
        return resultString;
    }
}

/**
 * 禁止重復(fù)提交
 */
@Target(ElementType.METHOD)
@Retention(RetentionPolicy.RUNTIME)
public @interface NotRepeatSubmit {
    /** 過期時(shí)間，單位毫秒 **/
    long value() default 5000;
}

@Data
@AllArgsConstructor
public class AccessToken {
    /** token */
    private String token;

    /** 失效時(shí)間 */
    private Date expireTime;
}

@Data
@NoArgsConstructor
@AllArgsConstructor
public class AppInfo {
    /** App id */
    private String appId;
    /** API 秘鑰 */
    private String key;
}

@Data
public class TokenInfo {
    /** token類型: api:0 、user:1 */
    private Integer tokenType;

    /** App 信息 */
    private AppInfo appInfo;

    /** 用戶其他數(shù)據(jù) */
    private UserInfo userInfo;
}

@Data
public class UserInfo {
    /** 用戶名 */
    private String username;
    /** 手機(jī)號(hào) */
    private String mobile;
    /** 郵箱 */
    private String email;
    /** 密碼 */
    private String password;
    /** 鹽 */
    private String salt;

    private AccessToken accessToken;

    public UserInfo(String username, String password, String salt) {
        this.username = username;
        this.password = password;
        this.salt = salt;
    }
}

/**
 * 錯(cuò)誤碼code可以使用純數(shù)字,使用不同區(qū)間標(biāo)識(shí)一類錯(cuò)誤，也可以使用純字符，也可以使用前綴+編號(hào)
 *
 * 錯(cuò)誤碼：ERR + 編號(hào)
 *
 * 可以使用日志級(jí)別的前綴作為錯(cuò)誤類型區(qū)分 Info(I) Error(E) Warning(W)
 *
 * 或者以業(yè)務(wù)模塊 + 錯(cuò)誤號(hào)
 *
 * TODO 錯(cuò)誤碼設(shè)計(jì)
 *
 * Alipay 用了兩個(gè)code，兩個(gè)msg(https://docs.open.alipay.com/api_1/alipay.trade.pay)
 */
public enum ApiCodeEnum {
    SUCCESS("10000", "success"),
    UNKNOW_ERROR("ERR0001","未知錯(cuò)誤"),
    PARAMETER_ERROR("ERR0002","參數(shù)錯(cuò)誤"),
    TOKEN_EXPIRE("ERR0003","認(rèn)證過期"),
    REQUEST_TIMEOUT("ERR0004","請(qǐng)求超時(shí)"),
    SIGN_ERROR("ERR0005","簽名錯(cuò)誤"),
    REPEAT_SUBMIT("ERR0006","請(qǐng)不要頻繁操作"),
    ;

    /** 代碼 */
    private String code;

    /** 結(jié)果 */
    private String msg;

    ApiCodeEnum(String code, String msg) {
        this.code = code;
        this.msg = msg;
    }

    public String getCode() {
        return code;
    }

    public String getMsg() {
        return msg;
    }
}

@Data
@NoArgsConstructor
@AllArgsConstructor
public class ApiResult {

    /** 代碼 */
    private String code;

    /** 結(jié)果 */
    private String msg;
}

public class ApiUtil {

    /**
     * 按參數(shù)名升續(xù)拼接參數(shù)
     * @param request
     * @return
     */
    public static String concatSignString(HttpServletRequest request) {
        Map<String, String> paramterMap = new HashMap<>();
        request.getParameterMap().forEach((key, value) -> paramterMap.put(key, value[0]));
        // 按照key升續(xù)排序，然后拼接參數(shù)
        Set<String> keySet = paramterMap.keySet();
        String[] keyArray = keySet.toArray(new String[keySet.size()]);
        Arrays.sort(keyArray);
        StringBuilder sb = new StringBuilder();
        for (String k : keyArray) {
            // 或略掉的字段
            if (k.equals("sign")) {
                continue;
            }
            if (paramterMap.get(k).trim().length() > 0) {
                // 參數(shù)值為空，則不參與簽名
                sb.append(k).append("=").append(paramterMap.get(k).trim()).append("&");
            }
        }

        return sb.toString();
    }

    public static String concatSignString(Map<String, String> map) {
        Map<String, String> paramterMap = new HashMap<>();
        map.forEach((key, value) -> paramterMap.put(key, value));
        // 按照key升續(xù)排序，然后拼接參數(shù)
        Set<String> keySet = paramterMap.keySet();
        String[] keyArray = keySet.toArray(new String[keySet.size()]);
        Arrays.sort(keyArray);
        StringBuilder sb = new StringBuilder();
        for (String k : keyArray) {
            if (paramterMap.get(k).trim().length() > 0) {
                // 參數(shù)值為空，則不參與簽名
                sb.append(k).append("=").append(paramterMap.get(k).trim()).append("&");
            }
        }
        return sb.toString();
    }

    /**
     * 獲取方法上的@NotRepeatSubmit注解
     * @param handler
     * @return
     */
    public static NotRepeatSubmit getNotRepeatSubmit(Object handler) {
        if (handler instanceof HandlerMethod) {
            HandlerMethod handlerMethod = (HandlerMethod) handler;
            Method method = handlerMethod.getMethod();
            NotRepeatSubmit annotation = method.getAnnotation(NotRepeatSubmit.class);

            return annotation;
        }

        return null;
    }
}

@Data
@Slf4j
public class ApiResponse<T> {
    /** 結(jié)果 */
    private ApiResult result;

    /** 數(shù)據(jù) */
    private T data;

    /** 簽名 */
    private String sign;


    public static <T> ApiResponse success(T data) {
        return response(ApiCodeEnum.SUCCESS.getCode(), ApiCodeEnum.SUCCESS.getMsg(), data);
    }

    public static ApiResponse error(String code, String msg) {
        return response(code, msg, null);
    }

    public static <T> ApiResponse response(String code, String msg, T data) {
        ApiResult result = new ApiResult(code, msg);
        ApiResponse response = new ApiResponse();
        response.setResult(result);
        response.setData(data);

        String sign = signData(data);
        response.setSign(sign);

        return response;
    }

    private static <T> String signData(T data) {
        // TODO 查詢key
        String key = "12345678954556";
        Map<String, String> responseMap = null;
        try {
            responseMap = getFields(data);
        } catch (IllegalAccessException e) {
            return null;
        }
        String urlComponent = ApiUtil.concatSignString(responseMap);
        String signature = urlComponent + "key=" + key;
        String sign = MD5Util.encode(signature);

        return sign;
    }

    /**
     * @param data 反射的對(duì)象,獲取對(duì)象的字段名和值
     * @throws IllegalArgumentException
     * @throws IllegalAccessException
     */
    public static Map<String, String> getFields(Object data) throws IllegalAccessException, IllegalArgumentException {
        if (data == null) return null;
        Map<String, String> map = new HashMap<>();
        Field[] fields = data.getClass().getDeclaredFields();
        for (int i = 0; i < fields.length; i++) {
            Field field = fields[i];
            field.setAccessible(true);

            String name = field.getName();
            Object value = field.get(data);
            if (field.get(data) != null) {
                map.put(name, value.toString());
            }
        }

        return map;
    }
}

• ThreadLocalUtil.set("key", value); 保存值

• T value = ThreadLocalUtil.get("key"); 獲取值

public class ThreadLocalUtil<T> {
    private static final ThreadLocal<Map<String, Object>> threadLocal = new ThreadLocal() {
        @Override
        protected Map<String, Object> initialValue() {
            return new HashMap<>(4);
        }
    };


    public static Map<String, Object> getThreadLocal(){
        return threadLocal.get();
    }

    public static <T> T get(String key) {
        Map map = (Map)threadLocal.get();
        return (T)map.get(key);
    }

    public static <T> T get(String key,T defaultValue) {
        Map map = (Map)threadLocal.get();
        return (T)map.get(key) == null ? defaultValue : (T)map.get(key);
    }

    public static void set(String key, Object value) {
        Map map = (Map)threadLocal.get();
        map.put(key, value);
    }

    public static void set(Map<String, Object> keyValueMap) {
        Map map = (Map)threadLocal.get();
        map.putAll(keyValueMap);
    }

    public static void remove() {
        threadLocal.remove();
    }

    public static <T> Map<String,T> fetchVarsByPrefix(String prefix) {
        Map<String,T> vars = new HashMap<>();
        if( prefix == null ){
            return vars;
        }
        Map map = (Map)threadLocal.get();
        Set<Map.Entry> set = map.entrySet();

        for( Map.Entry entry : set){
            Object key = entry.getKey();
            if( key instanceof String ){
                if( ((String) key).startsWith(prefix) ){
                    vars.put((String)key,(T)entry.getValue());
                }
            }
        }
        return vars;
    }

    public static <T> T remove(String key) {
        Map map = (Map)threadLocal.get();
        return (T)map.remove(key);
    }

    public static void clear(String prefix) {
        if( prefix == null ){
            return;
        }
        Map map = (Map)threadLocal.get();
        Set<Map.Entry> set = map.entrySet();
        List<String> removeKeys = new ArrayList<>();

        for( Map.Entry entry : set ){
            Object key = entry.getKey();
            if( key instanceof String ){
                if( ((String) key).startsWith(prefix) ){
                    removeKeys.add((String)key);
                }
            }
        }
        for( String key : removeKeys ){
            map.remove(key);
        }
    }
}