一、攻击说明

XSS

跨站脚本攻击(Cross Site Scripting)，为不和层叠样式表(Cascading Style Sheets, CSS)的缩写混淆，故将跨站脚本攻击缩写为XSS。恶意攻击者往Web页面里插入恶意html代码，当用户浏览该页之时，嵌入其中Web里面的html代码会被执行，从而达到恶意攻击用户的特殊目的。

sql注入

所谓SQL注入，就是通过把SQL命令插入到Web表单提交或输入域名或页面请求的查询字符串，最终达到欺骗服务器执行恶意的SQL命令。具体来说，它是利用现有应用程序，将（恶意）的SQL命令注入到后台数据库引擎执行的能力，它可以通过在Web表单中输入（恶意）SQL语句得到一个存在安全漏洞的网站上的数据库，而不是按照设计者意图去执行SQL语句。

二、解决办法

Step1：过滤器类XssAndSqlFilter.java

      package com.cup.cms.web.framework.filter;
      import java.io.IOException;
      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;
      /**
      * @Author Justin
      * @Date 2017年11月11日
      */
      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 {
      XssAndSqlHttpServletRequestWrapper xssRequest = new XssAndSqlHttpServletRequestWrapper(
      (HttpServletRequest) request);
      chain.doFilter(xssRequest, response);
      }
      @Override
      public void init(FilterConfig arg0) throws ServletException {
      // TODO Auto-generated method stub
      }
      }
  
 

Step2：包装器类XssAndSqlHttpServletRequestWrapper.java

      package com.cup.cms.web.framework.filter;
      import java.util.regex.Pattern;
      import javax.servlet.http.HttpServletRequest;
      import javax.servlet.http.HttpServletRequestWrapper;
      /**
      * @Author Justin
      * @Date 2017年11月11日
      */
      public class XssAndSqlHttpServletRequestWrapper extends
      HttpServletRequestWrapper {
      HttpServletRequest orgRequest = null;
      public XssAndSqlHttpServletRequestWrapper(HttpServletRequest request) {
      super(request);
      orgRequest = request;
      }
      /**
      * 覆盖getParameter方法，将参数名和参数值都做xss & sql过滤。
      * 如果需要获得原始的值，则通过super.getParameterValues(name)来获取
      * getParameterNames,getParameterValues和getParameterMap也可能需要覆盖
      */
      @Override
      public String getParameter(String name) {
      String value = super.getParameter(xssEncode(name));
      if (value != null) {
      value = xssEncode(value);
      }
      return value;
      }
      /**
      * 覆盖getHeader方法，将参数名和参数值都做xss & sql过滤。
      * 如果需要获得原始的值，则通过super.getHeaders(name)来获取 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(
      "<[\r\n| | ]*script[\r\n| | ]*>(.*?)</[\r\n| | ]*script[\r\n| | ]*>",
      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[\r\n| | ]*=[\r\n| | ]*[\\\"|\\\'](.*?)[\\\"|\\\']",
      Pattern.CASE_INSENSITIVE | Pattern.MULTILINE
      | Pattern.DOTALL);
      value = scriptPattern.matcher(value).replaceAll("");
      // Remove any lonesome </script> tag
      scriptPattern = Pattern.compile("</[\r\n| | ]*script[\r\n| | ]*>",
      Pattern.CASE_INSENSITIVE);
      value = scriptPattern.matcher(value).replaceAll("");
      // Remove any lonesome <script ...> tag
      scriptPattern = Pattern.compile("<[\r\n| | ]*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[\r\n| | ]*:[\r\n| | ]*",
      Pattern.CASE_INSENSITIVE);
      value = scriptPattern.matcher(value).replaceAll("");
      // Avoid vbscript:... expressions
      scriptPattern = Pattern.compile("vbscript[\r\n| | ]*:[\r\n| | ]*",
      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;
      }
      }
  
 

Step3：项目添加配置WEB-INF/web.xml

      <!-- 解决xss & sql漏洞 -->
      <filter>
      <filter-name>xssAndSqlFilter</filter-name>
      <filter-class>com.cup.cms.web.framework.filter.XssAndSqlFilter</filter-class>
      </filter>
      <!-- 解决xss & sql漏洞 -->
      <filter-mapping>
      <filter-name>xssAndSqlFilter</filter-name>
      <url-pattern>*</url-pattern>
      </filter-mapping>
  
 

文章来源: blog.csdn.net，作者：吾日三省贾斯汀，版权归原作者所有，如需转载，请联系作者。

原文链接：blog.csdn.net/JustinQin/article/details/78563497