Spring Boot 防止XSS攻击_springboot防止xss攻击

• XSS

跨站脚本工具（cross 斯特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ScriptScript代码，当用户浏览该页之时，嵌入其中Web里面的Script代码会被执行，从而达到恶意攻击用户的目的。防止XSS攻击简单的预防就是对Request请求中的一些参数去掉一些比较敏感的脚本命令。原本是打算通过SpringMVC的HandlerInterceptor机制来实现的，通过获取request然后对request中的参数进行修改，结果虽然值修改了，但在Controller中获取的数值还是没有修改的。没办法就是要Filter来完成。简单来说就是创建一个新的HttpRequest类XssHttpServletRequestWrapper，然后重写一些get方法（获取参数时对参数进行XSS判断预防）

流程梳理

包装request->创建过滤器->添加过滤器

1. 创建包装request的类 XssHttpServletRequestWrapper

 
import java.io.BufferedReader;
import java.io.ByteArrayInputStream;
import java.io.IOException;
import java.io.InputStreamReader;
import java.nio.charset.Charset;
import java.util.regex.Matcher;
import java.util.regex.Pattern;
 
import javax.servlet.ReadListener;
import javax.servlet.ServletInputStream;
import javax.servlet.ServletOutputStream;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletRequestWrapper;
import javax.servlet.http.HttpServletResponse;
 
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
 
import com.sysware.framework.exceptions.SyswareRuntimeException;
import com.sysware.framework.file.service.impl.FileGridServiceImpl;
 
 
public class XssHttpServletRequestWraper extends HttpServletRequestWrapper {
 
    private Logger log = LoggerFactory.getLogger(FileGridServiceImpl.class);
 
 
    public XssHttpServletRequestWraper() {
        super(null);
    }
 
    public XssHttpServletRequestWraper(HttpServletRequest httpservletrequest) {
        super(httpservletrequest);
        
    }
 
 //过滤springmvc中的 @RequestParam 注解中的参数
    public String[] getParameterValues(String s) {
 
        String str[] = super.getParameterValues(s);
        if (str == null) {
            return null;
        }
        int i = str.length;
        String as1[] = new String[i];
        for (int j = 0; j < i; j++) {
            //System.out.println("getParameterValues:"+str[j]);
            as1[j] = cleanXSS(cleanSQLInject(str[j]));
        }
        log.info("XssHttpServletRequestWraper净化后的请求为：==========" + as1);
        return as1;
    }
 
 //过滤request.getParameter的参数
    public String getParameter(String s) {
        String s1 = super.getParameter(s);
        if (s1 == null) {
            return null;
        } else {
            String s2 = cleanXSS(cleanSQLInject(s1));
            log.info("XssHttpServletRequestWraper净化后的请求为：==========" + s2);
            return s2;
        }
    }
 
 //过滤请求体 json 格式的
    @Override
    public ServletInputStream getInputStream() throws IOException {
        final ByteArrayInputStream bais = new ByteArrayInputStream(inputHandlers(super.getInputStream ()).getBytes ());
 
        return new ServletInputStream() {
 
            @Override
            public int read() throws IOException {
                return bais.read();
            }
 
            @Override
            public boolean isFinished() {
                return false;
            }
 
            @Override
            public boolean isReady() {
                return false;
            }
 
            @Override
            public void setReadListener(ReadListener readListener) { }
        };
        
    }
 
 
    public   String inputHandlers(ServletInputStream servletInputStream){
        StringBuilder sb = new StringBuilder();
        BufferedReader reader = null;
        try {
            reader = new BufferedReader(new InputStreamReader(servletInputStream, Charset.forName("UTF-8")));
            String line = "";
            while ((line = reader.readLine()) != null) {
                sb.append(line);
            }
        } catch (IOException e) {
            e.printStackTrace();
        } finally {
            if (servletInputStream != null) {
                try {
                    servletInputStream.close();
                } catch (IOException e) {
                    e.printStackTrace();
                }
            }
            if (reader != null) {
                try {
                    reader.close();
                } catch (IOException e) {
                    e.printStackTrace();
                }
            }
        }
        return  cleanXSS(sb.toString ());
    }
 
    public String cleanXSS(String src) {
        String temp = src;
 
        src = src.replaceAll("<", "＜").replaceAll(">", "＞");
        src = src.replaceAll("\\(", "（").replaceAll("\\)", "）");
        src = src.replaceAll("'", "");
        src = src.replaceAll(";", "");
        /**-----------------------start--------------------------*/
        src = src.replaceAll("<", "& lt;").replaceAll(">", "& gt;");
        src = src.replaceAll("\\(", "& #40;").replaceAll("\\)", "& #41");
        src = src.replaceAll("eval\\((.*)\\)", "");
        src = src.replaceAll("[\\\"\\\'][\\s]*javascript:(.*)[\\\"\\\']", "\"\"");
//        src = src.replaceAll("script", "");
//        src = src.replaceAll("link", "");
//        src = src.replaceAll("frame", "");
        /**-----------------------end--------------------------*/
        Pattern pattern = Pattern.compile("(eval\\((.*)\\)|script)",
                Pattern.CASE_INSENSITIVE);
        Matcher matcher = pattern.matcher(src);
        src = matcher.replaceAll("");
 
        pattern = Pattern.compile("[\\\"\\'][\\s]*javascript:(.*)[\\\"\\']",
                Pattern.CASE_INSENSITIVE);
        matcher = pattern.matcher(src);
        src = matcher.replaceAll("\"\"");
 
        // 增加脚本
        src = src.replaceAll("script", "").replaceAll(";", "")
                /*.replaceAll("\"", "").replaceAll("@", "")*/
                .replaceAll("0x0d", "").replaceAll("0x0a", "");
 
//        if (!temp.equals(src)) {
//            // System.out.println("输入信息存在xss攻击！");
//            // System.out.println("原始输入信息-->" + temp);
//            // System.out.println("处理后信息-->" + src);
// 
//            log.error("xss攻击检查：参数含有非法攻击字符，已禁止继续访问！！");
//            log.error("原始输入信息-->" + temp);
// 
//            throw new SyswareRuntimeException("xss攻击检查：参数含有非法攻击字符，已禁止继续访问！！");
//        }
        return src;
    }
 
    //输出
    public void outputMsgByOutputStream(HttpServletResponse response, String msg) throws IOException {
        ServletOutputStream outputStream = response.getOutputStream(); //获取输出流
        response.setHeader("content-type", "text/html;charset=UTF-8"); //通过设置响应头控制浏览器以UTF-8的编码显示数据，如果不加这句话，那么浏览器显示的将是乱码
        byte[] dataByteArr = msg.getBytes("UTF-8");// 将字符转换成字节数组，指定以UTF-8编码进行转换
        outputStream.write(dataByteArr);// 使用OutputStream流向客户端输出字节数组
    }
 
    // 需要增加通配，过滤大小写组合
    public String cleanSQLInject(String src) {
        String lowSrc = src.toLowerCase();
        String temp = src;
        String lowSrcAfter = lowSrc.replaceAll(" insert ", "forbidI")
                .replaceAll(" select ", "forbidS")
                .replaceAll(" update ", "forbidU")
                .replaceAll(" delete ", "forbidD").replaceAll(" and ", "forbidA")
                .replaceAll(" or ", "forbidO").replace("'", "");
 
        if (!lowSrcAfter.equals(lowSrc)) {
            log.error("sql注入检查：输入信息存在SQL攻击！");
            log.error("原始输入信息-->" + temp);
            log.error("处理后信息-->" + lowSrc);
            throw new SyswareRuntimeException("sql注入检查：参数含有非法攻击字符，已禁止继续访问！！");
 
        }
        return src;
    }
 
}

注意：
getInputStream()方法的流处理，注解方式获取数据貌似是根据这个流取得的数据。
因为super.getInputStream()流只允许读取一次，所以在getInputStream()方法中
处理完流数据后返回了一个新的ServletInputStream。另外替换方法里的替换规则，
也可以根据实际业务需要进行调整。

2.创建过滤器 XssFilter

@Component
public class XssFilter implements Filter {
 
 
    // 忽略权限检查的url地址
    private final String[] excludeUrls = new String[]{
    		"/api/item","api/document"
    };
 
    public void doFilter(ServletRequest arg0, ServletResponse arg1, FilterChain arg2)
            throws IOException, ServletException {
 
        HttpServletRequest req = (HttpServletRequest) arg0;
        HttpServletResponse response = (HttpServletResponse) arg1;
 
        String pathInfo = req.getPathInfo() == null ? "" : req.getPathInfo();
        //获取请求url的后两层
        String url = req.getServletPath() + pathInfo;
        //获取请求你ip后的全部路径
        String uri = req.getRequestURI();
        //注入xss过滤器实例
        XssHttpServletRequestWraper reqW = new XssHttpServletRequestWraper(req);
 
        //过滤掉不需要的Xss校验的地址
        for (String str : excludeUrls) {
            if (uri.indexOf(str) >= 0) {
            	//过滤
                arg2.doFilter(reqW, response);
                return;
            }
        }
        arg2.doFilter(arg0, response);
    }
    public void destroy() {
    }
    public void init(FilterConfig filterconfig1) throws ServletException {
    }
}