防止sql流入

防止sql注入

我们在开发系统的时候，总是要防止sql注入的，下面是我采用过滤器方式来阻止sql注入的，感觉效率很慢的，所以各位有好的方式请推荐。

过滤器代码：

package com.zbxsoft.uct.auth;

import java.io.IOException;
import java.util.Enumeration;

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.zbxsoft.tools.LogUtil;
import com.zbxsoft.tools.StrUtil;
/**
 * 防止sql攻击过滤器
 * @author qmhao
 * @version 1.2.3
 */
public class SqlFilter implements Filter {
	static String[] splitSql = null;
	static String errorPage = "/";
	/**
	 * 初始化
	 */
	public void init(FilterConfig arg0) throws ServletException {
		String ep = arg0.getInitParameter("errorPage");// 读配置文件
		if (ep != null) {
			errorPage = ep;
		}

		String sqlStr = arg0.getInitParameter("sqlStr");// 读配置文件
		if (sqlStr != null) {
			splitSql = sqlStr.split("\\|");
		}
	}

	public void destroy() {
	}

	/**
	 * 执行过滤
	 */
	public void doFilter(ServletRequest srequest, ServletResponse sresponse,
			FilterChain chain) throws ServletException, IOException {

		HttpServletRequest request = (HttpServletRequest) srequest;
		HttpServletResponse response = (HttpServletResponse) sresponse;
		response.setCharacterEncoding("UTF-8");

		if (splitSql != null && splitSql.length > 0) {
			Enumeration enum1 = request.getParameterNames();

			while (enum1.hasMoreElements()) {
				String param = enum1.nextElement().toString();
				String value = request.getParameter(param);
				LogUtil.info("------sqlFilter: value="+value);
				if (!isCorrectContent(value)) {
					response.setContentType("text/html;charset=UTF-8");
					response.getWriter().write("<script>alert('请求参数中含有非法字符!');</script>");
					LogUtil.error(">>>>>>>>>>>>>>sql过滤未通过!!param:"+param+"value:"+value);
					return ;
				}
			}
		}
		LogUtil.debug(">>>>>>>>>>>>>>sql过滤通过!!");
		chain.doFilter(request, response);

	}

	/**
	 * 判断是否是安全值
	 * @param paraValue
	 * @return boolean true是安全的，false为不安排的
	 */
	public static synchronized boolean isCorrectContent(String paraValue) {
		if (StrUtil.isNull(paraValue)) {
			return true;
		}
		for (int i = 0; i < splitSql.length; i++) {
			if (paraValue.toLowerCase().indexOf(splitSql[i]) != -1) {
//			if (paraValue.toLowerCase().equals(splitSql[i])) {
				return false;
			}
		}
		return true;
	}
}

 

 

web.xml配置

<!-- 安全过滤器：sql注入，敏感词 -->
	<filter>
		<filter-name>sqlFilter</filter-name>
		<filter-class>com.zbxsoft.uct.auth.SqlFilter</filter-class>		
		<init-param>
			<param-name>sqlStr</param-name>
			<param-value>grant|exec|execute|insert|drop|select|delete|update|truncate|declare</param-value>
		</init-param>
		<init-param>
			<param-name>errorPage</param-name>
			<param-value>/common/error.jsp</param-value>
		</init-param>		
	</filter>