一.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.demo.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; } 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; } 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 } }; } }
二.第二步
写过滤器：
package com.demo.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(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; } } } if (xssRequest.checkParameter()) { 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; } }
三.第三步
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() { 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; } }
备注：
-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。