XSS简介

た入场券 2022-02-15 05:21 234阅读 0赞

XSS攻击全称是跨站脚本攻击，是经常出现在web应用中的安全漏洞，它允许恶意web用户将代码植入到页面中，比如：sql脚本，javaSrcipt脚本，或者html代码。  
 解决方案：主要用到org.apache.commons.lang3.StringEscapeUtils.escapeHtml4()这个方法来对特殊字符进行转义。  
1、在web.xml中配置Filter

<filter>  
        <filter-name>XssEscape</filter-name>  
            <filter-class>cn.pconline.morden.filter.XssFilter</filter-class>  
        </filter>  
        <filter-mapping>  
            <filter-name>XssEscape</filter-name>  
            <url-pattern>/*</url-pattern>  
            <dispatcher>REQUEST</dispatcher>  
        </filter-mapping>

2、编写XssFilter类。实现Filter接口

public class XssFilter implements Filter {  
              
            @Override  
            public void init(FilterConfig filterConfig) throws ServletException {  
            }  
          
            @Override  
            public void doFilter(ServletRequest request, ServletResponse response,  
                    FilterChain chain) throws IOException, ServletException {  
                chain.doFilter(new XssHttpServletRequestWrapper((HttpServletRequest) request), response);  
            }  
          
            @Override  
            public void destroy() {  
            }  
        }

3、编写XssHttpServletRequestWrapper类。继承HttpServletRequestWrapper，并重写相应的几个有可能带xss攻击的方法

public class XssHttpServletRequestWrapper extends HttpServletRequestWrapper {  
          
            public XssHttpServletRequestWrapper(HttpServletRequest request) {  
                super(request);  
            }  
          
            @Override  
            public String getHeader(String name) {  
                return StringEscapeUtils.escapeHtml4(super.getHeader(name));  
            }  
          
            @Override  
            public String getQueryString() {  
                return StringEscapeUtils.escapeHtml4(super.getQueryString());  
            }  
          
            @Override  
            public String getParameter(String name) {  
                return StringEscapeUtils.escapeHtml4(super.getParameter(name));  
            }  
          
            @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++){  
                        escapseValues[i] = StringEscapeUtils.escapeHtml4(values[i]);  
                    }  
                    return escapseValues;  
                }  
                return super.getParameterValues(name);  
            }  
              
        }