import java.io.IOException;
import java.util.Iterator;
import java.util.Map;
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 javax.servlet.http.HttpSession;
import org.apache.commons.lang.StringUtils;

/**
 * 进入拦截器（所有请求都会进入）
 */
public class SessionFilter implements Filter {
	public void destroy() {
	}

	public void doFilter(ServletRequest servletRequest, ServletResponse servletResponse, FilterChain filterChain)
    throws IOException, ServletException
  {
    HttpServletRequest request = (HttpServletRequest)servletRequest;
    HttpServletResponse response = (HttpServletResponse)servletResponse;
    String requestStr = getRequestString(request);
    System.out.println("requestStr： ======================== " + requestStr);
   // 请求地址
    System.out.println("完整的地址是===="+request.getRequestURL().toString());
   //请求方法
  System.out.println("提交的方式是========"+request.getMethod()); 
 if("bingo".equals(guolv2(requestStr))||"bingo".equals(guolv2(request.getRequestURL().toString()))){
  System.out.println("======访问地址发现非法字符，已拦截======");
  response.sendRedirect(request.getContextPath() + "/login.jsp");
        return;
 }
 //主机ip和端口  或 域名和端口 
 String myhosts = request.getHeader("host");
   if(!StringUtils.equals(myhosts, "xx.xx.xxx.xxx:xxxx") && !StringUtils.equals(myhosts, "xx.xx.xxx.xxx:xxxx") 
     && !StringUtils.equals(myhosts, "xx.xx.xxx.xxx:xxxx")&&!StringUtils.equals(myhosts, "xx.xx.xxx.xxx") 
     && !StringUtils.equals(myhosts, "xx.xx.xxx.xxx") && !StringUtils.equals(myhosts, "xx.xx.xxx.xxx") ){
    System.out.println("======访问host非法，已拦截======");
    response.sendRedirect(request.getContextPath() + "/login.jsp");
       return;
 }
 
    String currentURL = request.getRequestURI();
     //过滤请求特殊字符，扫描跨站式漏洞
        Map parameters = request.getParameterMap();                //获取所有请求参数
        if (parameters != null && parameters.size() > 0) {
            for (Iterator iter = parameters.keySet().iterator(); iter.hasNext();) {
                String key = (String) iter.next();
                String[] values = (String[]) parameters.get(key);
                for (int i = 0; i < values.length; i++) {
                 values[i]=guolv(values[i]);                      //对参数关键字进行替换
                 System.out.println(values[i]);
                }
            }
        }

	// 初始化
	public void init(FilterConfig filterConfig) throws ServletException {
	}

	// 对所有关键字替换为空（特别是文本域）
	public static String guolv(String a) {
		a = a.replaceAll("%22", "");
		a = a.replaceAll("%27", "");
		a = a.replaceAll("%3E", "");
		a = a.replaceAll("%3e", "");
		a = a.replaceAll("%3C", "");
		a = a.replaceAll("%3c", "");
		a = a.replaceAll("<", "");
		a = a.replaceAll(">", "");
		a = a.replaceAll("\"", "");
		a = a.replaceAll("'", "");
		a = a.replaceAll("\\+", "");
		a = a.replaceAll("\\(", "");
		a = a.replaceAll("\\)", "");
		a = a.replaceAll(" and ", "");
		a = a.replaceAll(" or ", "");
		a = a.replaceAll(" 1=1 ", "");
		return a;
	}

	private String getRequestString(HttpServletRequest req) {
		String requestPath = req.getServletPath().toString();
		String queryString = req.getQueryString();
		if (queryString != null)
			return requestPath + "?" + queryString;
		else
			return requestPath;
	}

	// 对所有关键字替换为空（防止sql注入）
	public String guolv2(String a) {
		if (StringUtils.isNotEmpty(a)) {
			if (a.contains("%22") || a.contains("%3E") || a.contains("%3e")
					|| a.contains("%3C") || a.contains("%3c")
					|| a.contains("<") || a.contains(">") || a.contains("\"")
					|| a.contains("'") || a.contains("+") || /*
															 * a.contains("%27")
															 * ||
															 */
					a.contains(" and ") || a.contains(" or ")
					|| a.contains("1=1") || a.contains("(") || a.contains(")")) {
				return "bingo";
			}
		}
		return a;
	}

}