package com.cnblogs.tangyouwei.common.util;
import java.util.regex.Matcher;
import java.util.regex.Pattern;
/**
* @author 唐有炜
*/
public class XssUtil {
private static Pattern[] patterns = new Pattern[]{
// Script fragments
Pattern.compile("<script>(.*?)</script>", Pattern.CASE_INSENSITIVE),
// src='...'
Pattern.compile("src[\r\n]*=[\r\n]*\\\'(.*?)\\\'", Pattern.CASE_INSENSITIVE | Pattern.MULTILINE | Pattern.DOTALL),
Pattern.compile("src[\r\n]*=[\r\n]*\\\"(.*?)\\\"", Pattern.CASE_INSENSITIVE | Pattern.MULTILINE | Pattern.DOTALL),
// lonely script tags
Pattern.compile("</script>", Pattern.CASE_INSENSITIVE),
Pattern.compile("<script(.*?)>", Pattern.CASE_INSENSITIVE | Pattern.MULTILINE | Pattern.DOTALL),
// eval(...)
Pattern.compile("eval\\((.*?)\\)", Pattern.CASE_INSENSITIVE | Pattern.MULTILINE | Pattern.DOTALL),
// expression(...)
Pattern.compile("expression\\((.*?)\\)", Pattern.CASE_INSENSITIVE | Pattern.MULTILINE | Pattern.DOTALL),
// javascript:...
Pattern.compile("javascript:", Pattern.CASE_INSENSITIVE),
// vbscript:...
Pattern.compile("vbscript:", Pattern.CASE_INSENSITIVE),
// 空格英文单双引号
Pattern.compile("[\\s\'\"]+", Pattern.CASE_INSENSITIVE),
// onload(...)=...
Pattern.compile("onload(.*?)=", Pattern.CASE_INSENSITIVE | Pattern.MULTILINE | Pattern.DOTALL),
// alert
Pattern.compile("alert(.*?)", Pattern.CASE_INSENSITIVE | Pattern.MULTILINE | Pattern.DOTALL),
Pattern.compile("<", Pattern.MULTILINE | Pattern.DOTALL),
Pattern.compile(">", Pattern.MULTILINE | Pattern.DOTALL),
//Checks any html tags i.e. <script, <embed, <object etc.
Pattern.compile("(<(script|iframe|embed|frame|frameset|object|img|applet|body|html|style|layer|link|ilayer|meta|bgsound))")
};
/**
* xss替换函数
*
* @param value 需要替换的字符
* @return 替换后的字符
*/
public static String stripXSS(String value) {
if (value != null) {
// TODO ESAPI library
// 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("\0", "");
// Remove all sections that match a pattern
for (Pattern scriptPattern : patterns) {
value = scriptPattern.matcher(value).replaceAll("");
}
}
return value;
}
/**
* xss校验函数
*
* @param value 需要校验的字符
* @return 返回值:true 表示存在xss漏洞,false:不存在
*/
public static boolean checkIsXSS(String value) {
boolean isXss = false;
if (value != null) {
for (Pattern scriptPattern : patterns) {
Matcher matcher = scriptPattern.matcher(value);
if (matcher.find()) {
isXss = true;
break;
}
}
}
return isXss;
}
public static void main(String[] args) {
String str = "这是正常字符";
boolean result = XssUtil.checkIsXSS(str);
System.out.println(str + " 是否包含XSS字符:" + result);
String str2 = "这是xss字符\'\"<script>alert(111111)</script>";
boolean result2 = XssUtil.checkIsXSS(str2);
System.out.println(str2 + " 是否包含XSS字符:" + result2);
}
}