1.什么是XSS攻击
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，srcipt脚本，或者html代码。
黑客界共识是：跨站脚本攻击是新型的缓冲区溢出攻击。
例如：在页面输入一个转账的sql或者js脚本，然后发给后台，后台接收浏览器参数，没有任何校验，接着执行了该脚本，造成数据被篡改。
2.如何防御XSS攻击
我的项目是springboot项目，要防御XSS攻击只需要增加一个filter，然后在filter中包装http请求。
Talk is cheap，show me the code！
import javax.servlet.*;
import javax.servlet.annotation.WebFilter;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import java.io.IOException;
/**
* Created by shaomaolin on 2018/9/6.
*/
@WebFilter(urlPatterns = "/*", filterName = "XssFilter")
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 {
HttpServletResponse servletResponse = (HttpServletResponse)response;
servletResponse.setHeader("Set-Cookie", "name=value; HttpOnly");
chain.doFilter(new XssHttpServletRequestWrapper((HttpServletRequest) request), servletResponse);
}
@Override
public void destroy() {
}
}
import org.apache.commons.lang.StringEscapeUtils;
import org.apache.commons.lang3.StringUtils;
import org.springframework.web.util.HtmlUtils;
import org.springframework.web.util.JavaScriptUtils;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletRequestWrapper;
/**
* Created by shaomaolin on 2018/9/6.
*/
public class XssHttpServletRequestWrapper extends HttpServletRequestWrapper{
public XssHttpServletRequestWrapper(HttpServletRequest request) {
super(request);
}
public String[] getParameterValues(String parameter) {
String[] values = super.getParameterValues(parameter);
if (values == null)
return null;
int count = values.length;
String[] encodedValues = new String[count];
for (int i = 0; i < count; i++) {
encodedValues[i] = cleanXSS(values[i]);
}
return encodedValues;
}
public String getParameter(String parameter) {
String value = super.getParameter(parameter);
if (StringUtils.isBlank(value))
return null;
return cleanXSS(value);
}
private String cleanXSS(String value) {
if (StringUtils.isNotBlank(value)) {
value = HtmlUtils.htmlEscape(value);
value = JavaScriptUtils.javaScriptEscape(value);
value = StringEscapeUtils.escapeSql(value);
}
return value;
}
}
有同学说加了filter不起作用，是因为filter没有注册到spring容器中，解决办法：在springboot的main方法中加上下面注解：
@ServletComponentScan("com.shml.buka.xss")
