1.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.wb.common;
import java.io.BufferedReader;
import java.io.ByteArrayInputStream;
import java.io.IOException;
import java.io.InputStreamReader;
import java.util.Enumeration;
import java.util.HashMap;
import java.util.Map;
import java.util.Set;
import java.util.Vector;
import java.util.regex.Pattern;
import javax.servlet.ReadListener;
import javax.servlet.ServletInputStream;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletRequestWrapper;
import org.springframework.util.StreamUtils;
import com.sgcc.uap.utils.stream.StreamUtil;
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 onload= expressions
scriptPattern = Pattern.compile("onload(.*?)=",
Pattern.CASE_INSENSITIVE | Pattern.MULTILINE | Pattern.DOTALL);
value = scriptPattern.matcher(value).replaceAll("");
}
return value;
}
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 onload= expressions
scriptPattern = Pattern.compile("onload(.*?)=",
Pattern.CASE_INSENSITIVE | Pattern.MULTILINE | Pattern.DOTALL);
flag = scriptPattern.matcher(value).find();
if (flag) {
return flag;
}
}
return flag;
}
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;
}
@Override
public BufferedReader getReader() throws IOException {
return new BufferedReader(new InputStreamReader(getInputStream()));
}
@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
}
};
}
}
2.过滤器
package com.wb.common;
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 org.apache.commons.lang3.StringUtils;
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";
String param = "";
XssAndSqlHttpServletRequestWrapper xssRequest = null;
if (request instanceof HttpServletRequest) {
method = ((HttpServletRequest) request).getMethod();
xssRequest = new XssAndSqlHttpServletRequestWrapper((HttpServletRequest) request);
}
if ("POST".equalsIgnoreCase(method)) {
param = this.getBodyString(xssRequest.getReader());
if(StringUtils.isNotBlank(param)){
if(xssRequest.checkXSSAndSql(param)){
response.setCharacterEncoding("UTF-8");
response.setContentType("application/json;charset=UTF-8");
PrintWriter out = response.getWriter();
out.write(JSONResponseUtil.getWrappedERRString("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;
}
}
}
if (xssRequest.checkParameter()) {
response.setCharacterEncoding("UTF-8");
response.setContentType("application/json;charset=UTF-8");
PrintWriter out = response.getWriter();
out.write(JSONResponseUtil.getWrappedERRString("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;
}
}
3.注册过滤器XssAndSqlFilter。
@Bean
public FilterRegistrationBean xssFilterRegistrationBean() {
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;
}
-excludes用于配置不需要参数过滤的请求url;
-isIncludeRichText默认为true,主要用于设置富文本内容是否需要过滤。