package com.jyc.common.filter;
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.jyc.common.utils.StringUtils;
/**
* 防止XSS攻击的过滤器
*
* @author jianyongchao
*/
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;