SpringBoot——防止sql注入，xss攻击

sql注入：把SQL命令插入到Web表单递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。

解决方法：

（1）无论是直接使用数据库还是使用如mybatis组件，使用sql的预编译，不要用拼接字符串；

（2）后台过滤检测：使用正则表达式过滤传入的参数**；**.字符串过滤；

（4）前端检测sql常见关键字，如or and drop之类的。

xss攻击：其原理是攻击者向有XSS漏洞的网站中输入(传入)恶意的HTML代码，当其它用户浏览该网站时，这段HTML代码会自动执行，从而达到攻击的目的。

如，盗取用户Cookie、破坏页面结构、重定向到其它网站等。

解决方法：对用户输入的表单信息进行检测过滤。

第一步

创建XssAndSqlHttpServletRequestWrapper包装器，这是实现XSS过滤的关键，在其内重写了getParameter，getParameterValues，getHeader等方法，对http请求内的参数进行了过滤。

package com.gannan.court.config;

import org.springframework.util.StreamUtils;

import javax.servlet.ReadListener;
import javax.servlet.ServletInputStream;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletRequestWrapper;
import java.io.BufferedReader;
import java.io.ByteArrayInputStream;
import java.io.IOException;
import java.io.InputStreamReader;
import java.util.*;
import java.util.regex.Pattern;

/**
* @ClassName: XssAndSqlHttpServletRequestWrapper
* @Description: TODO
* @Author: zsl
* @Date: 2020/11/12 14:56
* @Version: v1.0
*/
public class XssAndSqlHttpServletRequestWrapper extends HttpServletRequestWrapper {
HttpServletRequest orgRequest = null;
private Map<String, String[]> parameterMap;
private final byte[] body; //用于保存读取body中数据

public XssAndSqlHttpServletRequestWrapper(HttpServletRequest request) throws IOException{
super(request);
orgRequest = request;
parameterMap = request.getParameterMap();
body = StreamUtils.copyToByteArray(request.getInputStream());
}

// 重写几个HttpServletRequestWrapper中的方法
/**
* 获取所有参数名
*
* @return 返回所有参数名
*/
@Override
public Enumeration<String> getParameterNames() {
Vector<String> vector = new Vector<String>(parameterMap.keySet());
return vector.elements();
}

/**
* 覆盖getParameter方法，将参数名和参数值都做xss & sql过滤。<br/>
* 如果需要获得原始的值，则通过super.getParameterValues(name)来获取<br/>
* getParameterNames,getParameterValues和getParameterMap也可能需要覆盖
*/
@Override
public String getParameter(String name) {
String[] results = parameterMap.get(name);
if (results == null || results.length <= 0)
return null;
else {
String value = results[0];
if (value != null) {
value = xssEncode(value);
}
return value;
}
}

/**
* 获取指定参数名的所有值的数组，如：checkbox的所有数据 接收数组变量 ，如checkobx类型
*/
@Override
public String[] getParameterValues(String name) {
String[] results = parameterMap.get(name);
if (results == null || results.length <= 0)
return null;
else {
int length = results.length;
for (int i = 0; i < length; i++) {
results[i] = xssEncode(results[i]);
}
return results;
}
}

/**
* 覆盖getHeader方法，将参数名和参数值都做xss & sql过滤。<br/>
* 如果需要获得原始的值，则通过super.getHeaders(name)来获取<br/>
* 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 οnlοad= expressions
scriptPattern = Pattern.compile(“onload(.*?)=”,
Pattern.CASE_INSENSITIVE | Pattern.MULTILINE | Pattern.DOTALL);
value = scriptPattern.matcher(value).replaceAll(“”);
}
return value;
}

/**
* 审查参数的具体方法
* @param value
* @return
*/
public static boolean checkXSSAndSql(String value) {
boolean flag = false;
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);
flag = scriptPattern.matcher(value).find();
if (flag) {
return flag;
}
// 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);
flag = scriptPattern.matcher(value).find();
if (flag) {
return flag;
}
// Remove any lonesome </script> tag
scriptPattern = Pattern.compile(“</[\r\n| | ]*script[\r\n| | ]*>”, Pattern.CASE_INSENSITIVE);
flag = scriptPattern.matcher(value).find();
if (flag) {
return flag;
}
// Remove any lonesome <script …> tag
scriptPattern = Pattern.compile(“<[\r\n| | ]*script(.*?)>”,
Pattern.CASE_INSENSITIVE | Pattern.MULTILINE | Pattern.DOTALL);
flag = scriptPattern.matcher(value).find();
if (flag) {
return flag;
}
// Avoid eval(…) expressions
scriptPattern = Pattern.compile(“eval\\((.*?)\\)”,
Pattern.CASE_INSENSITIVE | Pattern.MULTILINE | Pattern.DOTALL);
flag = scriptPattern.matcher(value).find();
if (flag) {
return flag;
}
// Avoid e-xpression(…) expressions
scriptPattern = Pattern.compile(“e-xpression\\((.*?)\\)”,
Pattern.CASE_INSENSITIVE | Pattern.MULTILINE | Pattern.DOTALL);
flag = scriptPattern.matcher(value).find();
if (flag) {
return flag;
}
// Avoid javascript:… expressions
scriptPattern = Pattern.compile(“javascript[\r\n| | ]*:[\r\n| | ]*”, Pattern.CASE_INSENSITIVE);
flag = scriptPattern.matcher(value).find();
if (flag) {
return flag;
}
// Avoid vbscript:… expressions
scriptPattern = Pattern.compile(“vbscript[\r\n| | ]*:[\r\n| | ]*”, Pattern.CASE_INSENSITIVE);
flag = scriptPattern.matcher(value).find();
if (flag) {
return flag;
}
// Avoid οnlοad= expressions
scriptPattern = Pattern.compile(“onload(.*?)=”,
Pattern.CASE_INSENSITIVE | Pattern.MULTILINE | Pattern.DOTALL);
flag = scriptPattern.matcher(value).find();
if (flag) {
return flag;
}
scriptPattern = Pattern.compile(“\\b(and|exec|insert|select|drop|grant|alter|delete|update|count|chr|mid|master|truncate|char|declare|or)\\b|(\\*|;|\\+|’|%)”,
Pattern.CASE_INSENSITIVE | Pattern.MULTILINE | Pattern.DOTALL);
flag = scriptPattern.matcher(value).find();
if (flag) {
return flag;
}
}
return flag;
}

/**
* 检查参数方法
* @return
*/
public final boolean checkParameter() {
Map<String, String[]> submitParams = new HashMap(parameterMap);
Set<String> submitNames = submitParams.keySet();
for (String submitName : submitNames) {
Object submitValues = submitParams.get(submitName);
if ((submitValues instanceof String)) {
if (checkXSSAndSql((String) submitValues)) {
return true;
}
} else if ((submitValues instanceof String[])) {
for (String submitValue : (String[])submitValues){
if (checkXSSAndSql(submitValue)) {
return true;
}
}
}
}
return false;
}

/**
**application/x- www-form-urlencoded是Post请求默认的请求体内容类型，也是form表单默认的类型。
* Servlet API规范中对该类型的请求内容提供了request.getParameter()方法来获取请求参数值。
* 但当请求内容不是该类型时，需要调用request.getInputStream()或request.getReader()方法来获取请求内容值。
*/
/**
* 获取请求内容
* @return
* @throws IOException
*/
@Override
public BufferedReader getReader() throws IOException {
return new BufferedReader(new InputStreamReader(getInputStream()));
}

/**
* 返回请求内容字节流，多用于文件上传，
* request.getReader()是对前者返回内容的封装，可以让调用者更方便字符内容的处理（不用自己先获取字节流再做字符流的转换操作）
* @return
* @throws IOException
*/
@Override
public ServletInputStream getInputStream() throws IOException {
final ByteArrayInputStream bais = new ByteArrayInputStream(body);
return new ServletInputStream() {

@Override
public int read() throws IOException {
return bais.read();
}

@Override
public boolean isFinished() {
// TODO Auto-generated method stub
return false;
}

@Override
public boolean isReady() {
// TODO Auto-generated method stub
return false;
}

@Override
public void setReadListener(ReadListener arg0) {
// TODO Auto-generated method stub

}
};
}

}

第二步

编写过滤器

package com.gannan.court.config;

import java.io.BufferedReader;
import java.io.IOException;
import java.io.PrintWriter;

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;

import com.alibaba.fastjson.JSONObject;
import io.micrometer.core.instrument.util.StringUtils;

/**
* @ClassName: XssAndSqlFilter
* @Description: TODO
* @Author: zsl
* @Date: 2020/11/12 14:57
* @Version: v1.0
*/

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 {
String method = “GET”;//设置初始值
String param = “”;
XssAndSqlHttpServletRequestWrapper xssRequest = null;
if (request instanceof HttpServletRequest) {//判断左边的对象是否是它右边对象的实例
method = ((HttpServletRequest) request).getMethod();//得到请求URL地址时使用的方法
xssRequest = new XssAndSqlHttpServletRequestWrapper((HttpServletRequest) request);//创建对象
}
if (“POST”.equalsIgnoreCase(method)) {//判断是否为post
param = this.getBodyString(xssRequest.getReader());//获取参数
if(StringUtils.isNotBlank(param)){//等价于 str != null && str.length > 0 && str.trim().length > 0
if(xssRequest.checkXSSAndSql(param)){//进行参数审查
response.setCharacterEncoding(“UTF-8”);
response.setContentType(“application/json;charset=UTF-8”);
PrintWriter out = response.getWriter();
out.write(JSONObject.toJSONString(“您所访问的页面请求中有违反安全规则元素存在，拒绝访问!”));
return;
}
}
}

/**
* 检查参数的时候 同时检查请求的方法
* 只检查get请求方法和post请求方法的的参数的数据是否合法
* 并不是所有参数都要检查，首先必须是一个get或者post，再去校验参数
* 因为PUT方法在进行参数审查的时候没办法通过所以直接过滤掉
*/
if (xssRequest.checkParameter()&&(method.equals(“POST”) || method.equals(“GET”))){
response.setCharacterEncoding(“UTF-8”);
response.setContentType(“application/json;charset=UTF-8”);
PrintWriter out = response.getWriter();
out.write(JSONObject.toJSONString(“您所访问的页面请求中有违反安全规则元素存在，拒绝访问!”));
return;
}
chain.doFilter(xssRequest, response);
}

@Override
public void init(FilterConfig arg0) throws ServletException {
// TODO Auto-generated method stub

}

// 获取request请求body中参数
public static String getBodyString(BufferedReader br) {
String inputLine;
String str = “”;
try {
while ((inputLine = br.readLine()) != null) {
str += inputLine;
}
br.close();
} catch (IOException e) {
System.out.println(“IOException: ” + e);
}
return str;

}
}

第三步

在webconfig中注册过滤器XssAndSqlFilter

package com.demo.config;

import java.util.Map;

import org.springframework.boot.web.servlet.FilterRegistrationBean;
import org.springframework.context.annotation.Bean;
import org.springframework.context.annotation.Configuration;

import com.beust.jcommander.internal.Maps;
import com.swireproperties.cams.common.filter.XssAndSqlFilter;

/**
* web配置
*/
@Configuration
public class WebConfig {

@Bean
public FilterRegistrationBean xssFilterRegistrationBean() {
//创建一个自定义的 Filter
FilterRegistrationBean filterRegistrationBean = new FilterRegistrationBean();
filterRegistrationBean.setFilter(new XssAndSqlFilter());
filterRegistrationBean.setOrder(1);
filterRegistrationBean.setEnabled(true);
filterRegistrationBean.addUrlPatterns(“/*”);
Map<String, String> initParameters = Maps.newHashMap();
initParameters.put(“excludes”, “/favicon.ico,/img/*,/js/*,/css/*”);
initParameters.put(“isIncludeRichText”, “true”);
filterRegistrationBean.setInitParameters(initParameters);
return filterRegistrationBean;
}

}