XssFilter EscapeUtil

package com.ruoyi.framework.config;

import java.util.HashMap;
import java.util.Map;
import javax.servlet.DispatcherType;
import org.springframework.beans.factory.annotation.Value;
import org.springframework.boot.web.servlet.FilterRegistrationBean;
import org.springframework.context.annotation.Bean;
import org.springframework.context.annotation.Configuration;
import com.ruoyi.common.utils.StringUtils;
import com.ruoyi.common.xss.XssFilter;

/**
 * Filter配置
 *
 * @author ruoyi
 */
@Configuration
public class FilterConfig
{
    @Value("${xss.enabled}")
    private String enabled;

    @Value("${xss.excludes}")
    private String excludes;

    @Value("${xss.urlPatterns}")
    private String urlPatterns;

    @SuppressWarnings({ "rawtypes", "unchecked" })
    @Bean
    public FilterRegistrationBean xssFilterRegistration()
    {
        FilterRegistrationBean registration = new FilterRegistrationBean();
        registration.setDispatcherTypes(DispatcherType.REQUEST);
        registration.setFilter(new XssFilter());
        registration.addUrlPatterns(StringUtils.split(urlPatterns, ","));
        registration.setName("xssFilter");
        registration.setOrder(Integer.MAX_VALUE);
        Map<String, String> initParameters = new HashMap<String, String>();
        initParameters.put("excludes", excludes);
        initParameters.put("enabled", enabled);
        registration.setInitParameters(initParameters);
        return registration;
    }
}

applicati.yml

# 防止XSS攻击
xss:
  # 过滤开关
  enabled: true
  # 排除链接（多个用逗号分隔）
  excludes: /system/notice/*
  # 匹配链接
  urlPatterns: /system/*,/monitor/*,/tool/*

package com.ruoyi.common.xss;

import java.io.IOException;
import java.util.ArrayList;
import java.util.List;
import java.util.regex.Matcher;
import java.util.regex.Pattern;
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 javax.servlet.http.HttpServletResponse;
import com.ruoyi.common.utils.StringUtils;

/**
 * 防止XSS攻击的过滤器
 *
 * @author ruoyi
 */
public class XssFilter implements Filter
{
    /**
     * 排除链接
     */
    public List<String> excludes = new ArrayList<>();

    /**
     * xss过滤开关
     */
    public boolean enabled = false;

    @Override
    public void init(FilterConfig filterConfig) throws ServletException
    {
        String tempExcludes = filterConfig.getInitParameter("excludes");
        String tempEnabled = filterConfig.getInitParameter("enabled");
        if (StringUtils.isNotEmpty(tempExcludes))
        {
            String[] url = tempExcludes.split(",");
            for (int i = 0; url != null && i < url.length; i++)
            {
                excludes.add(url[i]);
            }
        }
        if (StringUtils.isNotEmpty(tempEnabled))
        {
            enabled = Boolean.valueOf(tempEnabled);
        }
    }

    @Override
    public void doFilter(ServletRequest request, ServletResponse response, FilterChain chain)
            throws IOException, ServletException
    {
        HttpServletRequest req = (HttpServletRequest) request;
        HttpServletResponse resp = (HttpServletResponse) response;
        if (handleExcludeURL(req, resp))
        {
            chain.doFilter(request, response);
            return;
        }
        XssHttpServletRequestWrapper xssRequest = new XssHttpServletRequestWrapper((HttpServletRequest) request);
        chain.doFilter(xssRequest, response);
    }

    private boolean handleExcludeURL(HttpServletRequest request, HttpServletResponse response)
    {
        if (!enabled)
        {
            return true;
        }
        if (excludes == null || excludes.isEmpty())
        {
            return false;
        }
        String url = request.getServletPath();
        for (String pattern : excludes)
        {
            Pattern p = Pattern.compile("^" + pattern);
            Matcher m = p.matcher(url);
            if (m.find())
            {
                return true;
            }
        }
        return false;
    }

    @Override
    public void destroy()
    {

    }
}

package com.ruoyi.common.xss;

import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletRequestWrapper;
import com.ruoyi.common.utils.html.EscapeUtil;

/**
 * XSS过滤处理
 *
 * @author ruoyi
 */
public class XssHttpServletRequestWrapper extends HttpServletRequestWrapper
{
    /**
     * @param request
     */
    public XssHttpServletRequestWrapper(HttpServletRequest request)
    {
        super(request);
    }

    @Override
    public String[] getParameterValues(String name)
    {
        String[] values = super.getParameterValues(name);
        if (values != null)
        {
            int length = values.length;
            String[] escapseValues = new String[length];
            for (int i = 0; i < length; i++)
            {
                // 防xss攻击和过滤前后空格
                escapseValues[i] = EscapeUtil.clean(values[i]).trim();
            }
            return escapseValues;
        }
        return super.getParameterValues(name);
    }
}

package com.ruoyi.common.utils.html;

import com.ruoyi.common.utils.StringUtils;

/**
 * 转义和反转义工具类
 *
 * @author ruoyi
 */
public class EscapeUtil
{
    public static final String RE_HTML_MARK = "(<[^<]*?>)|(<[\\s]*?/[^<]*?>)|(<[^<]*?/[\\s]*?>)";

    private static final char[][] TEXT = new char[64][];

    static
    {
        for (int i = 0; i < 64; i++)
        {
            TEXT[i] = new char[] { (char) i };
        }

        // special HTML characters
        TEXT['\''] = "'".toCharArray(); // 单引号
        TEXT['"'] = """.toCharArray(); // 单引号
        TEXT['&'] = "&".toCharArray(); // &符
        TEXT['<'] = "<".toCharArray(); // 小于号
        TEXT['>'] = ">".toCharArray(); // 大于号
    }

    /**
     * 转义文本中的HTML字符为安全的字符
     *
     * @param text 被转义的文本
     * @return 转义后的文本
     */
    public static String escape(String text)
    {
        return encode(text);
    }

    /**
     * 还原被转义的HTML特殊字符
     *
     * @param content 包含转义符的HTML内容
     * @return 转换后的字符串
     */
    public static String unescape(String content)
    {
        return decode(content);
    }

    /**
     * 清除所有HTML标签，但是不删除标签内的内容
     *
     * @param content 文本
     * @return 清除标签后的文本
     */
    public static String clean(String content)
    {
        return content.replaceAll(RE_HTML_MARK, "");
    }

    /**
     * Escape编码
     *
     * @param text 被编码的文本
     * @return 编码后的字符
     */
    private static String encode(String text)
    {
        int len;
        if ((text == null) || ((len = text.length()) == 0))
        {
            return StringUtils.EMPTY;
        }
        StringBuilder buffer = new StringBuilder(len + (len >> 2));
        char c;
        for (int i = 0; i < len; i++)
        {
            c = text.charAt(i);
            if (c < 64)
            {
                buffer.append(TEXT[c]);
            }
            else
            {
                buffer.append(c);
            }
        }
        return buffer.toString();
    }

    /**
     * Escape解码
     *
     * @param content 被转义的内容
     * @return 解码后的字符串
     */
    public static String decode(String content)
    {
        if (StringUtils.isEmpty(content))
        {
            return content;
        }

        StringBuilder tmp = new StringBuilder(content.length());
        int lastPos = 0, pos = 0;
        char ch;
        while (lastPos < content.length())
        {
            pos = content.indexOf("%", lastPos);
            if (pos == lastPos)
            {
                if (content.charAt(pos + 1) == 'u')
                {
                    ch = (char) Integer.parseInt(content.substring(pos + 2, pos + 6), 16);
                    tmp.append(ch);
                    lastPos = pos + 6;
                }
                else
                {
                    ch = (char) Integer.parseInt(content.substring(pos + 1, pos + 3), 16);
                    tmp.append(ch);
                    lastPos = pos + 3;
                }
            }
            else
            {
                if (pos == -1)
                {
                    tmp.append(content.substring(lastPos));
                    lastPos = content.length();
                }
                else
                {
                    tmp.append(content.substring(lastPos, pos));
                    lastPos = pos;
                }
            }
        }
        return tmp.toString();
    }

    public static void main(String[] args)
    {
        String html = "<script>alert(1);</script>";
        System.out.println(EscapeUtil.clean(html));
        System.out.println(EscapeUtil.escape(html));
        System.out.println(EscapeUtil.unescape(html));
    }
}