场景：可以在页面输入框输入JS脚本， 攻击者可以利用此漏洞执行恶意的代码 ！
问题演示
所以我们要对于前端传输的参数做处理，做统一全局过滤处理
既然要过滤处理，我们首先需要实现一个自定义过滤器
总共包含以下四部分
-
XssUtil
-
XssFilterAutoConfig
-
XssHttpServletRequestWrapper
-
XssStringfJsonDeserializer
最后我们需要在全局过滤器中使用我们实现的Xss自定义过滤器
代码实现
XssFilterAtuoConfig实现代码
import com.fasterxml.jackson.databind.ObjectMapper;
import com.fasterxml.jackson.databind.module.SimpleModule;
import net.greatsoft.overallbudget.filter.SimpleCORSFilter;
import org.springframework.boot.context.embedded.FilterRegistrationBean;
import org.springframework.context.annotation.Bean;
import org.springframework.context.annotation.Configuration;
import org.springframework.context.annotation.Primary;
import org.springframework.http.converter.json.Jackson2ObjectMapperBuilder;
import org.springframework.http.converter.json.MappingJackson2HttpMessageConverter;
/**
* Created by wjy on 2020/11/5.
* xss 自动配置类
*/
@Configuration
public class XssFilterAtuoConfig {
/**
* 注册自定义过滤器
* @return
*/
@Bean
public FilterRegistrationBean xssFiltrRegister() {
FilterRegistrationBean registration = new FilterRegistrationBean();
//设置系统过滤器 (setFilter就是你所定义的过滤器filter类)
registration.setFilter(new SimpleCORSFilter());
//过滤所有路径
registration.addUrlPatterns("/*");
//过滤器名称
registration.setName("XssFilter");
//优先级
registration.setOrder(1);
return registration;
}
/**
* 过滤JSON数据
* @return
*/
@Bean
@Primary
public MappingJackson2HttpMessageConverter mappingJackson2HttpMessageConverter() {
SimpleModule module = new SimpleModule();
//自定义序列化过滤配置(XssStringJsonDeserializer), 对入参进行转译
module.addDeserializer(String.class, new XssStringJsonDeserializer());
// 注册解析器
ObjectMapper objectMapper = Jackson2ObjectMapperBuilder.json().build();
objectMapper.registerModule(module);
return new MappingJackson2HttpMessageConverter(objectMapper);
}
}
|
XssHttpServletRequestWrapper实现代码
/**
* Created by wjy on 2020/11/5.
* xss 包装
*/
public class XssHttpServletRequestWrapper extends HttpServletRequestWrapper {
public XssHttpServletRequestWrapper(HttpServletRequest request) {
super(request);
}
/**
* 对header处理
* @param name
* @return
*/
@Override
public String getHeader(String name) {
String value = super.getHeader(name);
return XssUtil.cleanXSS(value);
}
/**
* 对参数处理
* @param name
* @return
*/
@Override
public String getParameter(String name) {
String value = super.getParameter(name);
return XssUtil.cleanXSS(value);
}
/**
* 对数值进行处理
* @param name
* @return
*/
@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] = XssUtil.cleanXSS(values[i]);
}
return escapseValues;
}
return super.getParameterValues(name);
}
/**
* 主要是针对HandlerMapping.URI_TEMPLATE_VARIABLES_ATTRIBUTE 获取pathvalue的时候把原来的pathvalue经过xss过滤掉
*/
@Override
public Object getAttribute(String name) {
// 获取pathvalue的值
if (HandlerMapping.URI_TEMPLATE_VARIABLES_ATTRIBUTE.equals(name)) {
Map uriTemplateVars = (Map) super.getAttribute(HandlerMapping.URI_TEMPLATE_VARIABLES_ATTRIBUTE);
if (Objects.isNull(uriTemplateVars)) {
return uriTemplateVars;
}
Map newMap = new LinkedHashMap<>();
uriTemplateVars.forEach((key, value) -> {
if (value instanceof String) {
newMap.put(key, XssUtil.cleanXSS((String) value));
} else {
newMap.put(key, value);
}
});
return newMap;
} else {
return super.getAttribute(name);
}
}
}
|
XssStringJsonDeserializer代码实现
/**
* Created by wjy on 2020/11/5.
* 基于xss的JsonDeserializer
*/
public class XssStringJsonDeserializer extends JsonDeserializer<String> {
@Override
public Class<String> handledType() {
return String.class;
}
@Override
public String deserialize(JsonParser jsonParser, DeserializationContext deserializationContext) throws IOException {
return XssUtil.cleanXSS(jsonParser.getValueAsString());
}
}
|
XssUtil代码实现
/**
* Created by wjy on 2020/11/5.
* xss工具类
*/
public class XssUtil {
public static String cleanXSS(String value) {
if (Objects.isNull(value)) {
return value;
}
//在这里自定义需要过滤的字符
value = value.replaceAll("<", "& lt;").replaceAll(">", "& gt;");
value = value.replaceAll("(", "& #40;").replaceAll(")", "& #41;");
value = value.replaceAll("'", "& #39;");
value = value.replaceAll("eval((.*))", "");
value = value.replaceAll("["'][s]*javascript:(.*)["']", """");
value = value.replaceAll("<script>", "");
return value;
}
}
|
全局过滤器实现
@Component
public class SimpleCORSFilter implements Filter {
@Override
public void doFilter(ServletRequest req, ServletResponse res,
FilterChain chain) throws IOException, ServletException {
// 在这里，使用我们实现的XSS过滤器
XssHttpServletRequestWrapper request =
new XssHttpServletRequestWrapper((HttpServletRequest) req);
HttpServletResponse response = (HttpServletResponse) res;
response.setHeader("Access-Control-Allow-Origin", "*");
response.setHeader("Access-Control-Allow-Methods",
"POST, GET, PUT, OPTIONS, DELETE");
response.setHeader("Access-Control-Max-Age", "3600");
response.setHeader("Access-Control-Allow-Headers",
"Origin, X-Requested-With, Content-Type, Accept, token");
chain.doFilter(request, response);
}
public void init(FilterConfig filterConfig) {
}
public void destroy() {
}
}
|
|
