天天看點
傳回

「SpringCloud」(五十一) Gateway攔截器實作防止SQL注入/XSS攻擊

作者：AI全棧程式猿

  SQL注入是常見的系統安全問題之一，使用者通過特定方式向系統發送SQL腳本，可直接自定義作業系統資料庫，如果系統沒有對SQL注入進行攔截，那麼使用者甚至可以直接對資料庫進行增删改查等操作。

  XSS全稱為Cross Site Script跨站點腳本攻擊，和SQL注入類似，都是通過特定方式向系統發送攻擊腳本，對系統進行控制和侵害。SQL注入主要以攻擊資料庫來達到攻擊系統的目的，而XSS則是以惡意執行前端腳本來攻擊系統。

  項目架構中使用mybatis/mybatis-plus資料持久層架構，在使用過程中，已有規避SQL注入的規則和使用方法。但是在實際開發過程中，由于各種原因，開發人員對持久層架構的掌握水準不同，有些特殊業務情況必須從前台傳入SQL腳本。這時就需要對系統進行加強，防止特殊情況下引起的系統風險。

  在微服務架構下，我們考慮如何實作SQL注入/XSS攻擊攔截時，肯定不會在每個微服務都實作一遍SQL注入/XSS攻擊攔截。根據我們微服務系統的設計，所有的請求都會經過Gateway網關，是以在實作時就可以參照前面的日志攔截器來實作。在接收到一個請求時，通過攔截器解析請求參數，判斷是否有SQL注入/XSS攻擊參數，如果有，那麼傳回異常即可。

  我們前面在對微服務Gateway進行自定義擴充時，增加了Gateway插件功能。我們會根據系統需求開發各種Gateway功能擴充插件，并且可以根據系統配置檔案來啟用/禁用這些插件。下面我們就将防止SQL注入/XSS攻擊攔截器作為一個Gateway插件來開發和配置。

1、新增SqlInjectionFilter 過濾器和XssInjectionFilter過濾器，分别用于解析請求參數并對參數進行判斷是否存在SQL注入/XSS攻腳本。此處有公共判斷方法，通過配置檔案來讀取請求的過濾配置，因為不是多有的請求都會引發SQL注入和XSS攻擊，如果無差别的全部攔截和請求，那麼勢必影響到系統的性能。

  • 判斷SQL注入的攔截器 
/**
 * 防sql注入
 * @author GitEgg
 */
@Log4j2
@AllArgsConstructor
public class SqlInjectionFilter implements GlobalFilter, Ordered {

......

        // 當傳回參數為true時，解析請求參數和傳回參數
        if (shouldSqlInjection(exchange))
        {
            MultiValueMap<String, String> queryParams = request.getQueryParams();
            boolean chkRetGetParams = SqlInjectionRuleUtils.mapRequestSqlKeyWordsCheck(queryParams);
    
            boolean chkRetJson = false;
            boolean chkRetFormData = false;
            
            HttpHeaders headers = request.getHeaders();
            MediaType contentType = headers.getContentType();
            long length = headers.getContentLength();

            if(length > 0 && null != contentType && (contentType.includes(MediaType.APPLICATION_JSON)
                    ||contentType.includes(MediaType.APPLICATION_JSON_UTF8))){
                chkRetJson = SqlInjectionRuleUtils.jsonRequestSqlKeyWordsCheck(gatewayContext.getRequestBody());
            }
            
            if(length > 0 && null != contentType  && contentType.includes(MediaType.APPLICATION_FORM_URLENCODED)){
                log.debug("[RequestLogFilter](Request)FormData:{}",gatewayContext.getFormData());
                chkRetFormData = SqlInjectionRuleUtils.mapRequestSqlKeyWordsCheck(gatewayContext.getFormData());
            }
            
            if (chkRetGetParams || chkRetJson || chkRetFormData)
            {
                return WebfluxResponseUtils.responseWrite(exchange, "參數中不允許存在sql關鍵字");
            }
            return chain.filter(exchange);
        }
        else {
            return chain.filter(exchange);
        }
    }

......

}
  • 判斷XSS攻擊的攔截器 
/**
 * 防xss注入
 * @author GitEgg
 */
@Log4j2
@AllArgsConstructor
public class XssInjectionFilter implements GlobalFilter, Ordered {

 ......

        // 當傳回參數為true時，記錄請求參數和傳回參數
        if (shouldXssInjection(exchange))
        {
            MultiValueMap<String, String> queryParams = request.getQueryParams();
            boolean chkRetGetParams = XssInjectionRuleUtils.mapRequestSqlKeyWordsCheck(queryParams);
    
            boolean chkRetJson = false;
            boolean chkRetFormData = false;
            
            HttpHeaders headers = request.getHeaders();
            MediaType contentType = headers.getContentType();
            long length = headers.getContentLength();

            if(length > 0 && null != contentType && (contentType.includes(MediaType.APPLICATION_JSON)
                    ||contentType.includes(MediaType.APPLICATION_JSON_UTF8))){
                chkRetJson = XssInjectionRuleUtils.jsonRequestSqlKeyWordsCheck(gatewayContext.getRequestBody());
            }
            
            if(length > 0 && null != contentType  && contentType.includes(MediaType.APPLICATION_FORM_URLENCODED)){
                log.debug("[RequestLogFilter](Request)FormData:{}",gatewayContext.getFormData());
                chkRetFormData = XssInjectionRuleUtils.mapRequestSqlKeyWordsCheck(gatewayContext.getFormData());
            }
            
            if (chkRetGetParams || chkRetJson || chkRetFormData)
            {
                return WebfluxResponseUtils.responseWrite(exchange, "參數中不允許存在XSS注入關鍵字");
            }
            return chain.filter(exchange);
        }
        else {
            return chain.filter(exchange);
        }
    }

......

}

2、新增SqlInjectionRuleUtils工具類和XssInjectionRuleUtils工具類，通過正規表達式，用于判斷參數是否屬于SQL注入/XSS攻擊腳本。

  • 通過正規表達式對參數進行是否有SQL注入風險的判斷 
/**
 * 防sql注入工具類
 * @author GitEgg
 */
@Slf4j
public class SqlInjectionRuleUtils {
    
    /**
     * SQL的正規表達式
     */
    private static String badStrReg = "\\b(and|or)\\b.{1,6}?(=|>|<|\\bin\\b|\\blike\\b)|\\/\\*.+?\\*\\/|<\\s*script\\b|\\bEXEC\\b|UNION.+?SELECT|UPDATE.+?SET|INSERT\\s+INTO.+?VALUES|(SELECT|DELETE).+?FROM|(CREATE|ALTER|DROP|TRUNCATE)\\s+(TABLE|DATABASE)";
    
    /**
     * SQL的正規表達式
     */
    private static Pattern sqlPattern = Pattern.compile(badStrReg, Pattern.CASE_INSENSITIVE);
    
    
    /**
     * sql注入校驗 map
     *
     * @param map
     * @return
     */
    public static boolean mapRequestSqlKeyWordsCheck(MultiValueMap<String, String> map) {
        //對post請求參數值進行sql注入檢驗
        return map.entrySet().stream().parallel().anyMatch(entry -> {
            //這裡需要将參數轉換為小寫來處理
            String lowerValue = Optional.ofNullable(entry.getValue())
                    .map(Object::toString)
                    .map(String::toLowerCase)
                    .orElse("");
            if (sqlPattern.matcher(lowerValue).find()) {
                log.error("參數[{}]中包含不允許sql的關鍵詞", lowerValue);
                return true;
            }
            return false;
        });
    }
    
    
    /**
     *  sql注入校驗 json
     *
     * @param value
     * @return
     */
    public static boolean jsonRequestSqlKeyWordsCheck(String value) {
        if (JSONUtil.isJsonObj(value)) {
            JSONObject json = JSONUtil.parseObj(value);
            Map<String, Object> map = json;
            //對post請求參數值進行sql注入檢驗
            return map.entrySet().stream().parallel().anyMatch(entry -> {
                //這裡需要将參數轉換為小寫來處理
                String lowerValue = Optional.ofNullable(entry.getValue())
                        .map(Object::toString)
                        .map(String::toLowerCase)
                        .orElse("");
                if (sqlPattern.matcher(lowerValue).find()) {
                    log.error("參數[{}]中包含不允許sql的關鍵詞", lowerValue);
                    return true;
                }
                return false;
            });
        } else {
            JSONArray json = JSONUtil.parseArray(value);
            List<Object> list = json;
            //對post請求參數值進行sql注入檢驗
            return list.stream().parallel().anyMatch(obj -> {
                //這裡需要将參數轉換為小寫來處理
                String lowerValue = Optional.ofNullable(obj)
                        .map(Object::toString)
                        .map(String::toLowerCase)
                        .orElse("");
                if (sqlPattern.matcher(lowerValue).find()) {
                    log.error("參數[{}]中包含不允許sql的關鍵詞", lowerValue);
                    return true;
                }
                return false;
            });
        }
    }
}
  • 通過正規表達式對參數進行是否有XSS攻擊風險的判斷 
/**
 * XSS注入過濾工具類
 * @author GitEgg
 */
public class XssInjectionRuleUtils {
    
    private static final Pattern[] PATTERNS = {
            
            // Avoid anything in a <script> type of expression
            Pattern.compile("<script>(.*?)</script>", Pattern.CASE_INSENSITIVE),
            // Avoid anything in a src='...' type of expression
            Pattern.compile("src[\r\n]*=[\r\n]*\\\'(.*?)\\\'", Pattern.CASE_INSENSITIVE | Pattern.MULTILINE | Pattern.DOTALL),
            Pattern.compile("src[\r\n]*=[\r\n]*\\\"(.*?)\\\"", Pattern.CASE_INSENSITIVE | Pattern.MULTILINE | Pattern.DOTALL),
            // Remove any lonesome </script> tag
            Pattern.compile("</script>", Pattern.CASE_INSENSITIVE),
            // Avoid anything in a <iframe> type of expression
            Pattern.compile("<iframe>(.*?)</iframe>", Pattern.CASE_INSENSITIVE),
            // Remove any lonesome <script ...> tag
            Pattern.compile("<script(.*?)>", Pattern.CASE_INSENSITIVE | Pattern.MULTILINE | Pattern.DOTALL),
            // Remove any lonesome <img ...> tag
            Pattern.compile("<img(.*?)>", Pattern.CASE_INSENSITIVE | Pattern.MULTILINE | Pattern.DOTALL),
            // Avoid eval(...) expressions
            Pattern.compile("eval\\((.*?)\\)", Pattern.CASE_INSENSITIVE | Pattern.MULTILINE | Pattern.DOTALL),
            // Avoid expression(...) expressions
            Pattern.compile("expression\\((.*?)\\)", Pattern.CASE_INSENSITIVE | Pattern.MULTILINE | Pattern.DOTALL),
            // Avoid javascript:... expressions
            Pattern.compile("javascript:", Pattern.CASE_INSENSITIVE),
            // Avoid vbscript:... expressions
            Pattern.compile("vbscript:", Pattern.CASE_INSENSITIVE),
            // Avoid onload= expressions
            Pattern.compile("on(load|error|mouseover|submit|reset|focus|click)(.*?)=", Pattern.CASE_INSENSITIVE | Pattern.MULTILINE | Pattern.DOTALL)
    };
    
    public static String stripXSS(String value) {
        if (StringUtils.isEmpty(value)) {
            return value;
        }
        for (Pattern scriptPattern : PATTERNS) {
            value = scriptPattern.matcher(value).replaceAll("");
        }
        return value;
    }
    
    public static boolean hasStripXSS(String value) {
        if (!StringUtils.isEmpty(value)) {
            for (Pattern scriptPattern : PATTERNS) {
                if (scriptPattern.matcher(value).find() == true)
                {
                    return true;
                }
            }
        }
        return false;
    }
    
    /**
     * xss注入校驗 map
     *
     * @param map
     * @return
     */
    public static boolean mapRequestSqlKeyWordsCheck(MultiValueMap<String, String> map) {
        //對post請求參數值進行sql注入檢驗
        return map.entrySet().stream().parallel().anyMatch(entry -> {
            //這裡需要将參數轉換為小寫來處理
            String lowerValue = Optional.ofNullable(entry.getValue())
                    .map(Object::toString)
                    .map(String::toLowerCase)
                    .orElse("");
            if (hasStripXSS(lowerValue)) {
                return true;
            }
            return false;
        });
    }
    
    
    /**
     *  xss注入校驗 json
     *
     * @param value
     * @return
     */
    public static boolean jsonRequestSqlKeyWordsCheck(String value) {
        if (JSONUtil.isJsonObj(value)) {
            JSONObject json = JSONUtil.parseObj(value);
            Map<String, Object> map = json;
            //對post請求參數值進行sql注入檢驗
            return map.entrySet().stream().parallel().anyMatch(entry -> {
                //這裡需要将參數轉換為小寫來處理
                String lowerValue = Optional.ofNullable(entry.getValue())
                        .map(Object::toString)
                        .map(String::toLowerCase)
                        .orElse("");
                if (hasStripXSS(lowerValue)) {
                    return true;
                }
                return false;
            });
        } else {
            JSONArray json = JSONUtil.parseArray(value);
            List<Object> list = json;
            //對post請求參數值進行sql注入檢驗
            return list.stream().parallel().anyMatch(obj -> {
                //這裡需要将參數轉換為小寫來處理
                String lowerValue = Optional.ofNullable(obj)
                        .map(Object::toString)
                        .map(String::toLowerCase)
                        .orElse("");
                if (hasStripXSS(lowerValue)) {
                    return true;
                }
                return false;
            });
        }
    }
    
}

3、在GatewayRequestContextFilter 中新增判斷那些請求需要解析參數。因為出于性能等方面的考慮，網關并不是對所有的參數都進行解析，隻有在需要記錄日志、防止SQL注入/XSS攻擊時才會進行解析。 

/**
     * check should read request data whether or not
     * @return boolean
     */
    private boolean shouldReadRequestData(ServerWebExchange exchange){
        if(gatewayPluginProperties.getLogRequest().getRequestLog()
                && GatewayLogTypeEnum.ALL.getType().equals(gatewayPluginProperties.getLogRequest().getLogType())){
            log.debug("[GatewayContext]Properties Set Read All Request Data");
            return true;
        }

        boolean serviceFlag = false;
        boolean pathFlag = false;
        boolean lbFlag = false;

        List<String> readRequestDataServiceIdList = gatewayPluginProperties.getLogRequest().getServiceIdList();

        List<String> readRequestDataPathList = gatewayPluginProperties.getLogRequest().getPathList();

        if(!CollectionUtils.isEmpty(readRequestDataPathList)
                && (GatewayLogTypeEnum.PATH.getType().equals(gatewayPluginProperties.getLogRequest().getLogType())
                    || GatewayLogTypeEnum.CONFIGURE.getType().equals(gatewayPluginProperties.getLogRequest().getLogType()))){
            String requestPath = exchange.getRequest().getPath().pathWithinApplication().value();
            for(String path : readRequestDataPathList){
                if(ANT_PATH_MATCHER.match(path,requestPath)){
                    log.debug("[GatewayContext]Properties Set Read Specific Request Data With Request Path:{},Math Pattern:{}", requestPath, path);
                    pathFlag =  true;
                    break;
                }
            }
        }

        Route route = exchange.getAttribute(ServerWebExchangeUtils.GATEWAY_ROUTE_ATTR);
        URI routeUri = route.getUri();
        if(!"lb".equalsIgnoreCase(routeUri.getScheme())){
            lbFlag = true;
        }

        String routeServiceId = routeUri.getHost().toLowerCase();
        if(!CollectionUtils.isEmpty(readRequestDataServiceIdList)
                && (GatewayLogTypeEnum.SERVICE.getType().equals(gatewayPluginProperties.getLogRequest().getLogType())
                || GatewayLogTypeEnum.CONFIGURE.getType().equals(gatewayPluginProperties.getLogRequest().getLogType()))){
            if(readRequestDataServiceIdList.contains(routeServiceId)){
                log.debug("[GatewayContext]Properties Set Read Specific Request Data With ServiceId:{}",routeServiceId);
                serviceFlag =  true;
            }
        }

        if (GatewayLogTypeEnum.CONFIGURE.getType().equals(gatewayPluginProperties.getLogRequest().getLogType())
                && serviceFlag && pathFlag && !lbFlag)
        {
            return true;
        }
        else if (GatewayLogTypeEnum.SERVICE.getType().equals(gatewayPluginProperties.getLogRequest().getLogType())
                && serviceFlag && !lbFlag)
        {
            return true;
        }
        else if (GatewayLogTypeEnum.PATH.getType().equals(gatewayPluginProperties.getLogRequest().getLogType())
                && pathFlag)
        {
            return true;
        }

        return false;
    }

4、在GatewayPluginProperties中新增配置，用于讀取Gateway過濾器的系統配置，判斷開啟新增的防止SQL注入/XSS攻擊插件。 

@Slf4j
@Getter
@Setter
@ToString
public class GatewayPluginProperties implements InitializingBean {

    public static final String GATEWAY_PLUGIN_PROPERTIES_PREFIX = "spring.cloud.gateway.plugin.config";
    
    public static final String GATEWAY_PLUGIN_PROPERTIES_PREFIX_LOG_REQUEST = GATEWAY_PLUGIN_PROPERTIES_PREFIX + ".logRequest";
    
    public static final String GATEWAY_PLUGIN_PROPERTIES_PREFIX_SQL_INJECTION = GATEWAY_PLUGIN_PROPERTIES_PREFIX + ".sqlInjection";
    
    public static final String GATEWAY_PLUGIN_PROPERTIES_PREFIX_XSS_INJECTION = GATEWAY_PLUGIN_PROPERTIES_PREFIX + ".xssInjection";
    
    /**
     * Enable Or Disable
     */
    private Boolean enable = false;
    
    /**
     * LogProperties
     */
    private LogProperties logRequest;
    
    /**
     * SqlInjectionProperties
     */
    private SqlInjectionProperties sqlInjection;
    
    /**
     * XssInjectionProperties
     */
    private XssInjectionProperties xssInjection;

    @Override
    public void afterPropertiesSet() {
        log.info("Gateway plugin logRequest enable:", logRequest.enable);
        log.info("Gateway plugin sqlInjection enable:", sqlInjection.enable);
        log.info("Gateway plugin xssInjection enable:", xssInjection.enable);
    }
    
    /**
     * 日志記錄相關配置
     */
    @Getter
    @Setter
    @ToString
    public static class LogProperties implements InitializingBean{
    
        /**
         * Enable Or Disable Log Request Detail
         */
        private Boolean enable = false;
    
        /**
         * Enable Or Disable Read Request Data
         */
        private Boolean requestLog = false;
    
        /**
         * Enable Or Disable Read Response Data
         */
        private Boolean responseLog = false;
    
        /**
         * logType
         * all： 所有日志
         * configure:serviceId和pathList交集
         * serviceId： 隻記錄serviceId配置清單
         * pathList：隻記錄pathList配置清單
         */
        private String logType = "all";
    
        /**
         * Enable Read Request Data When use discover route by serviceId
         */
        private List<String> serviceIdList = Collections.emptyList();
    
        /**
         * Enable Read Request Data by specific path
         */
        private List<String> pathList = Collections.emptyList();
    
        @Override
        public void afterPropertiesSet() throws Exception {
            if(!CollectionUtils.isEmpty(serviceIdList)){
                serviceIdList = serviceIdList.stream().map(String::toLowerCase).collect(Collectors.toList());
            }
            if(!CollectionUtils.isEmpty(pathList)){
                pathList = pathList.stream().map(String::toLowerCase).collect(Collectors.toList());
            }
        }
    }
    
    /**
     * sql注入攔截相關配置
     */
    @Getter
    @Setter
    @ToString
    public static class SqlInjectionProperties implements InitializingBean{
        
        /**
         * Enable Or Disable
         */
        private Boolean enable = false;
        
        /**
         * Enable Read Request Data When use discover route by serviceId
         */
        private List<String> serviceIdList = Collections.emptyList();
        
        /**
         * Enable Read Request Data by specific path
         */
        private List<String> pathList = Collections.emptyList();
        
        @Override
        public void afterPropertiesSet() {
            if(!CollectionUtils.isEmpty(serviceIdList)){
                serviceIdList = serviceIdList.stream().map(String::toLowerCase).collect(Collectors.toList());
            }
            if(!CollectionUtils.isEmpty(pathList)){
                pathList = pathList.stream().map(String::toLowerCase).collect(Collectors.toList());
            }
        }
    }
    
    /**
     * xss注入攔截相關配置
     */
    @Getter
    @Setter
    @ToString
    public static class XssInjectionProperties implements InitializingBean{
        
        /**
         * Enable Or Disable
         */
        private Boolean enable = false;
        
        /**
         * Enable Read Request Data When use discover route by serviceId
         */
        private List<String> serviceIdList = Collections.emptyList();
        
        /**
         * Enable Read Request Data by specific path
         */
        private List<String> pathList = Collections.emptyList();
        
        @Override
        public void afterPropertiesSet() {
            if(!CollectionUtils.isEmpty(serviceIdList)){
                serviceIdList = serviceIdList.stream().map(String::toLowerCase).collect(Collectors.toList());
            }
            if(!CollectionUtils.isEmpty(pathList)){
                pathList = pathList.stream().map(String::toLowerCase).collect(Collectors.toList());
            }
        }
    }
}

5、GatewayPluginConfig 配置過濾器在啟動時動态判斷是否啟用某些Gateway插件。在這裡我們将新增的SQL注入攔截插件和XSS攻擊攔截插件配置進來，可以根據配置檔案動态判斷是否啟用SQL注入攔截插件和XSS攻擊攔截插件。

@Slf4j
@Configuration
@ConditionalOnProperty(prefix = GatewayPluginProperties.GATEWAY_PLUGIN_PROPERTIES_PREFIX, value = { "enable"}, havingValue = "true")
public class GatewayPluginConfig {
    
    /**
     * Gateway插件是否生效
     * @return
     */
    @Bean
    @ConditionalOnMissingBean(GatewayPluginProperties.class)
    @ConfigurationProperties(GatewayPluginProperties.GATEWAY_PLUGIN_PROPERTIES_PREFIX)
    public GatewayPluginProperties gatewayPluginProperties(){
        return new GatewayPluginProperties();
    }
    
......
    
    /**
     * sql注入攔截插件
     * @return
     */
    @Bean
    @ConditionalOnMissingBean(SqlInjectionFilter.class)
    @ConditionalOnProperty(prefix = GatewayPluginProperties.GATEWAY_PLUGIN_PROPERTIES_PREFIX, value = { "sqlInjection.enable" },havingValue = "true")
    public SqlInjectionFilter sqlInjectionFilter(@Autowired GatewayPluginProperties gatewayPluginProperties){
        SqlInjectionFilter sqlInjectionFilter = new SqlInjectionFilter(gatewayPluginProperties);
        log.debug("Load SQL Injection Filter Config Bean");
        return sqlInjectionFilter;
    }

    /**
     * xss注入攔截插件
     * @return
     */
    @Bean
    @ConditionalOnMissingBean(XssInjectionFilter.class)
    @ConditionalOnProperty(prefix = GatewayPluginProperties.GATEWAY_PLUGIN_PROPERTIES_PREFIX, value = { "xssInjection.enable" },havingValue = "true")
    public XssInjectionFilter xssInjectionFilter(@Autowired GatewayPluginProperties gatewayPluginProperties){
        XssInjectionFilter xssInjectionFilter = new XssInjectionFilter(gatewayPluginProperties);
        log.debug("Load XSS Injection Filter Config Bean");
        return xssInjectionFilter;
    }
......
}

  在日常開發過程中很多業務需求都不會從前端傳入SQL腳本和XSS腳本，是以很多的開發架構都不去識别前端參數是否有安全風險，然後直接禁止掉所有前端傳入的的腳本，這樣就強制規避了SQL注入和XSS攻擊的風險。但是在某些特殊業務情況下，尤其是傳統行業系統，需要通過前端配置執行腳本，然後由業務系統去執行這些配置的腳本，這個時候就需要通過配置來進行識别和判斷，然後對容易引起安全性風險的腳本進轉換和配置，在保證業務正常運作的情況下完成腳本配置。

源碼位址:

Gitee:

https://gitee.com/wmz1930/GitEgg

GitHub:

https://github.com/wmz1930/GitEgg

防止sql注入 SpringClou gateway spring pring ring Gate
上一篇: 一個稱職的項目經理應該要具備的能力
下一篇: SQL備份所有資料庫腳本

繼續閱讀