关于SpringBoot过滤器过滤get及post请求中的XSS和SQL注入

Posted 2021-03-01 zjoe80

一.第一步

创建XssAndSqlHttpServletRequestWrapper包装器，这是实现XSS过滤的关键，

在其内重写了getParameter，getParameterValues，getHeader等方法，对http请求内的参数进行了过滤。

package com.demo.common;

import java.io.BufferedReader;
import java.io.ByteArrayInputStream;
import java.io.IOException;
import java.io.InputStreamReader;
import java.util.Enumeration;
import java.util.HashMap;
import java.util.Map;
import java.util.Set;
import java.util.Vector;
import java.util.regex.Pattern;

import javax.servlet.ReadListener;
import javax.servlet.ServletInputStream;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletRequestWrapper;

import org.springframework.util.StreamUtils;

import com.sgcc.uap.utils.stream.StreamUtil;

public class XssAndSqlHttpServletRequestWrapper extends HttpServletRequestWrapper {

    HttpServletRequest orgRequest = null;
    private Map<String, String[]> parameterMap;
    private final byte[] body; //用于保存读取body中数据

    public XssAndSqlHttpServletRequestWrapper(HttpServletRequest request) throws IOException{
        super(request);
        orgRequest = request;
        parameterMap = request.getParameterMap();
        body = StreamUtils.copyToByteArray(request.getInputStream());
    }

    // 重写几个HttpServletRequestWrapper中的方法
    /**
     * 获取所有参数名
     *
     * @return 返回所有参数名
     */
    @Override
    public Enumeration<String> getParameterNames() {
        Vector<String> vector = new Vector<String>(parameterMap.keySet());
        return vector.elements();
    }

    /**
     * 覆盖getParameter方法，将参数名和参数值都做xss & sql过滤。<br/>
     * 如果需要获得原始的值，则通过super.getParameterValues(name)来获取<br/>
     * getParameterNames,getParameterValues和getParameterMap也可能需要覆盖
     */
    @Override
    public String getParameter(String name) {
        String[] results = parameterMap.get(name);
        if (results == null || results.length <= 0)
            return null;
        else {
            String value = results[0];
            if (value != null) {
                value = xssEncode(value);
            }
            return value;
        }
    }

    /**
     * 获取指定参数名的所有值的数组，如：checkbox的所有数据 接收数组变量 ，如checkobx类型
     */
    @Override
    public String[] getParameterValues(String name) {
        String[] results = parameterMap.get(name);
        if (results == null || results.length <= 0)
            return null;
        else {
            int length = results.length;
            for (int i = 0; i < length; i++) {
                results[i] = xssEncode(results[i]);
            }
            return results;
        }
    }

    /**
     * 覆盖getHeader方法，将参数名和参数值都做xss & sql过滤。<br/>
     * 如果需要获得原始的值，则通过super.getHeaders(name)来获取<br/>
     * getHeaderNames 也可能需要覆盖
     */
    @Override
    public String getHeader(String name) {

        String value = super.getHeader(xssEncode(name));
        if (value != null) {
            value = xssEncode(value);
        }
        return value;
    }

    /**
     * 将容易引起xss & sql漏洞的半角字符直接替换成全角字符
     * 
     * @param s
     * @return
     */
    private static String xssEncode(String s) {
        if (s == null || s.isEmpty()) {
            return s;
        } else {
            s = stripXSSAndSql(s);
        }
        StringBuilder sb = new StringBuilder(s.length() + 16);
        for (int i = 0; i < s.length(); i++) {
            char c = s.charAt(i);
            switch (c) {
            case ‘>‘:
                sb.append("＞");// 转义大于号
                break;
            case ‘<‘:
                sb.append("＜");// 转义小于号
                break;
            // case ‘‘‘:
            // sb.append("＇");// 转义单引号
            // break;
            // case ‘"‘:
            // sb.append("＂");// 转义双引号
            // break;
            case ‘&‘:
                sb.append("＆");// 转义&
                break;
            case ‘#‘:
                sb.append("＃");// 转义#
                break;
            default:
                sb.append(c);
                break;
            }
        }
        return sb.toString();
    }

    /**
     * 获取最原始的request
     * 
     * @return
     */
    public HttpServletRequest getOrgRequest() {
        return orgRequest;
    }

    /**
     * 获取最原始的request的静态方法
     * 
     * @return
     */
    public static HttpServletRequest getOrgRequest(HttpServletRequest req) {
        if (req instanceof XssAndSqlHttpServletRequestWrapper) {
            return ((XssAndSqlHttpServletRequestWrapper) req).getOrgRequest();
        }
        return req;
    }

    /**
     * 
     * 防止xss跨脚本攻击（替换，根据实际情况调整）
     */

    public static String stripXSSAndSql(String value) {
        if (value != null) {
            // NOTE: It‘s highly recommended to use the ESAPI library and
            // uncomment the following line to
            // avoid encoded attacks.
            // value = ESAPI.encoder().canonicalize(value);
            // Avoid null characters
            /** value = value.replaceAll("", ""); ***/
            // Avoid anything between script tags
            Pattern scriptPattern = Pattern.compile(
                    "<[
| | ]*script[
| | ]*>(.*?)</[
| | ]*script[
| | ]*>", Pattern.CASE_INSENSITIVE);
            value = scriptPattern.matcher(value).replaceAll("");
            // Avoid anything in a
            // src="http://www.yihaomen.com/article/java/..." type of
            // e-xpression
            scriptPattern = Pattern.compile("src[
| | ]*=[
| | ]*[\"|\‘](.*?)[\"|\‘]",
                    Pattern.CASE_INSENSITIVE | Pattern.MULTILINE | Pattern.DOTALL);
            value = scriptPattern.matcher(value).replaceAll("");
            // Remove any lonesome </script> tag
            scriptPattern = Pattern.compile("</[
| | ]*script[
| | ]*>", Pattern.CASE_INSENSITIVE);
            value = scriptPattern.matcher(value).replaceAll("");
            // Remove any lonesome <script ...> tag
            scriptPattern = Pattern.compile("<[
| | ]*script(.*?)>",
                    Pattern.CASE_INSENSITIVE | Pattern.MULTILINE | Pattern.DOTALL);
            value = scriptPattern.matcher(value).replaceAll("");
            // Avoid eval(...) expressions
            scriptPattern = Pattern.compile("eval\((.*?)\)",
                    Pattern.CASE_INSENSITIVE | Pattern.MULTILINE | Pattern.DOTALL);
            value = scriptPattern.matcher(value).replaceAll("");
            // Avoid e-xpression(...) expressions
            scriptPattern = Pattern.compile("e-xpression\((.*?)\)",
                    Pattern.CASE_INSENSITIVE | Pattern.MULTILINE | Pattern.DOTALL);
            value = scriptPattern.matcher(value).replaceAll("");
            // Avoid javascript:... expressions
            scriptPattern = Pattern.compile("javascript[
| | ]*:[
| | ]*", Pattern.CASE_INSENSITIVE);
            value = scriptPattern.matcher(value).replaceAll("");
            // Avoid vbscript:... expressions
            scriptPattern = Pattern.compile("vbscript[
| | ]*:[
| | ]*", Pattern.CASE_INSENSITIVE);
            value = scriptPattern.matcher(value).replaceAll("");
            // Avoid onload= expressions
            scriptPattern = Pattern.compile("onload(.*?)=",
                    Pattern.CASE_INSENSITIVE | Pattern.MULTILINE | Pattern.DOTALL);
            value = scriptPattern.matcher(value).replaceAll("");
        }
        return value;
    }

    public static boolean checkXSSAndSql(String value) {
        boolean flag = false;
        if (value != null) {
            // NOTE: It‘s highly recommended to use the ESAPI library and
            // uncomment the following line to
            // avoid encoded attacks.
            // value = ESAPI.encoder().canonicalize(value);
            // Avoid null characters
            /** value = value.replaceAll("", ""); ***/
            // Avoid anything between script tags
            Pattern scriptPattern = Pattern.compile(
                    "<[
| | ]*script[
| | ]*>(.*?)</[
| | ]*script[
| | ]*>", Pattern.CASE_INSENSITIVE);
            flag = scriptPattern.matcher(value).find();
            if (flag) {
                return flag;
            }
            // Avoid anything in a
            // src="http://www.yihaomen.com/article/java/..." type of
            // e-xpression
            scriptPattern = Pattern.compile("src[
| | ]*=[
| | ]*[\"|\‘](.*?)[\"|\‘]",
                    Pattern.CASE_INSENSITIVE | Pattern.MULTILINE | Pattern.DOTALL);
            flag = scriptPattern.matcher(value).find();
            if (flag) {
                return flag;
            }
            // Remove any lonesome </script> tag
            scriptPattern = Pattern.compile("</[
| | ]*script[
| | ]*>", Pattern.CASE_INSENSITIVE);
            flag = scriptPattern.matcher(value).find();
            if (flag) {
                return flag;
            }
            // Remove any lonesome <script ...> tag
            scriptPattern = Pattern.compile("<[
| | ]*script(.*?)>",
                    Pattern.CASE_INSENSITIVE | Pattern.MULTILINE | Pattern.DOTALL);
            flag = scriptPattern.matcher(value).find();
            if (flag) {
                return flag;
            }
            // Avoid eval(...) expressions
            scriptPattern = Pattern.compile("eval\((.*?)\)",
                    Pattern.CASE_INSENSITIVE | Pattern.MULTILINE | Pattern.DOTALL);
            flag = scriptPattern.matcher(value).find();
            if (flag) {
                return flag;
            }
            // Avoid e-xpression(...) expressions
            scriptPattern = Pattern.compile("e-xpression\((.*?)\)",
                    Pattern.CASE_INSENSITIVE | Pattern.MULTILINE | Pattern.DOTALL);
            flag = scriptPattern.matcher(value).find();
            if (flag) {
                return flag;
            }
            // Avoid javascript:... expressions
            scriptPattern = Pattern.compile("javascript[
| | ]*:[
| | ]*", Pattern.CASE_INSENSITIVE);
            flag = scriptPattern.matcher(value).find();
            if (flag) {
                return flag;
            }
            // Avoid vbscript:... expressions
            scriptPattern = Pattern.compile("vbscript[
| | ]*:[
| | ]*", Pattern.CASE_INSENSITIVE);
            flag = scriptPattern.matcher(value).find();
            if (flag) {
                return flag;
            }
            // Avoid onload= expressions
            scriptPattern = Pattern.compile("onload(.*?)=",
                    Pattern.CASE_INSENSITIVE | Pattern.MULTILINE | Pattern.DOTALL);
            flag = scriptPattern.matcher(value).find();
            if (flag) {
                return flag;
            }
           scriptPattern = Pattern.compile("\b(and|exec|insert|select|drop|grant|alter|delete|update|count|chr|mid|master|truncate|char|declare|or)\b|(\*|;|\+|‘|%)",
                    Pattern.CASE_INSENSITIVE | Pattern.MULTILINE | Pattern.DOTALL);
            flag = scriptPattern.matcher(value).find();
            if (flag) {
                return flag;
            }
        }
        return flag;
    }

    public final boolean checkParameter() {
        Map<String, String[]> submitParams = new HashMap(parameterMap);
        Set<String> submitNames = submitParams.keySet();
        for (String submitName : submitNames) {
            Object submitValues = submitParams.get(submitName);
            if ((submitValues instanceof String)) {
                if (checkXSSAndSql((String) submitValues)) {
                    return true;
                }
            } else if ((submitValues instanceof String[])) {
                for (String submitValue : (String[])submitValues){
                    if (checkXSSAndSql(submitValue)) {
                        return true;
                    }
                }
            }
        }
        return false;
    }
    
    @Override    
    public BufferedReader getReader() throws IOException {    
        return new BufferedReader(new InputStreamReader(getInputStream()));    
    }    
    
    @Override    
    public ServletInputStream getInputStream() throws IOException {    
        final ByteArrayInputStream bais = new ByteArrayInputStream(body);    
        return new ServletInputStream() {    
    
            @Override    
            public int read() throws IOException {    
                return bais.read();    
            }  

            @Override  
            public boolean isFinished() {  
                // TODO Auto-generated method stub  
                return false;  
            }  

            @Override  
            public boolean isReady() {  
                // TODO Auto-generated method stub  
                return false;  
            }  

            @Override  
            public void setReadListener(ReadListener arg0) {  
                // TODO Auto-generated method stub  
                  
            }    
        };    
    }

}

 

二.第二步

写过滤器：

package com.demo.common;

import java.io.BufferedReader;
import java.io.IOException;
import java.io.PrintWriter;

import javax.servlet.Filter;
import javax.servlet.FilterChain;
import javax.servlet.FilterConfig;
import javax.servlet.ServletException;
import javax.servlet.ServletRequest;
import javax.servlet.ServletResponse;
import javax.servlet.http.HttpServletRequest;

import org.apache.commons.lang3.StringUtils;

public class XssAndSqlFilter implements Filter {

    @Override
    public void destroy() {
        // TODO Auto-generated method stub

    }

    @Override
    public void doFilter(ServletRequest request, ServletResponse response, FilterChain chain)
            throws IOException, ServletException {
        String method = "GET";
        String param = "";
        XssAndSqlHttpServletRequestWrapper xssRequest = null;
        if (request instanceof HttpServletRequest) {
            method = ((HttpServletRequest) request).getMethod();
            xssRequest = new XssAndSqlHttpServletRequestWrapper((HttpServletRequest) request);
        }
        if ("POST".equalsIgnoreCase(method)) {
            param = this.getBodyString(xssRequest.getReader());
            if(StringUtils.isNotBlank(param)){
                if(xssRequest.checkXSSAndSql(param)){
                    response.setCharacterEncoding("UTF-8");
                    response.setContentType("application/json;charset=UTF-8");
                    PrintWriter out = response.getWriter();
                    out.write(JSONObject.toJSONString("您所访问的页面请求中有违反安全规则元素存在，拒绝访问!"));
                    return;
                }
            }
        }
        if (xssRequest.checkParameter()) {
            response.setCharacterEncoding("UTF-8");
            response.setContentType("application/json;charset=UTF-8");
            PrintWriter out = response.getWriter();
            out.write(JSONObject.toJSONString("您所访问的页面请求中有违反安全规则元素存在，拒绝访问!"));
            return;
        }
        chain.doFilter(xssRequest, response);
    }

    @Override
    public void init(FilterConfig arg0) throws ServletException {
        // TODO Auto-generated method stub

    }

    // 获取request请求body中参数
    public static String getBodyString(BufferedReader br) {
        String inputLine;
        String str = "";
        try {
            while ((inputLine = br.readLine()) != null) {
                str += inputLine;
            }
            br.close();
        } catch (IOException e) {
            System.out.println("IOException: " + e);
        }
        return str;

    }

}

 

三.第三步

注册过滤器XssAndSqlFilter。

package com.demo.config;

import java.util.Map;

import org.springframework.boot.web.servlet.FilterRegistrationBean;
import org.springframework.context.annotation.Bean;
import org.springframework.context.annotation.Configuration;

import com.beust.jcommander.internal.Maps;
import com.swireproperties.cams.common.filter.XssAndSqlFilter;

/**
 * web配置
 * 
 */
@Configuration
public class WebConfig {

    @Bean
    public FilterRegistrationBean xssFilterRegistrationBean() {
        FilterRegistrationBean filterRegistrationBean = new FilterRegistrationBean();
        filterRegistrationBean.setFilter(new XssAndSqlFilter());
        filterRegistrationBean.setOrder(1);
        filterRegistrationBean.setEnabled(true);
        filterRegistrationBean.addUrlPatterns("/*");
        Map<String, String> initParameters = Maps.newHashMap();
        initParameters.put("excludes", "/favicon.ico,/img/*,/js/*,/css/*");
        initParameters.put("isIncludeRichText", "true");
        filterRegistrationBean.setInitParameters(initParameters);
        return filterRegistrationBean;
    }

}

备注：

-excludes用于配置不需要参数过滤的请求url;
-isIncludeRichText默认为true，主要用于设置富文本内容是否需要过滤。