网站安全通用防护代码（用户读写数据库对用户输入或者发送（Post、Get）数据等进行检测过滤等）

每一个开发者都会意识到，网站发布之前，需要进行安全及系统漏洞检查。

那么如何拦截攻击者注入恶意脚本或代码？如何防御诸如跨站脚本攻击（XSS）、SQL注入攻击等恶意攻击行为？

针对目前常见的一些安全问题，结合目前一些常见的防护办法，可在系统底层增加了安全防护代码。

[Description("网站安全通用防护代码（用户读写数据库对用户输入或者发送（Post、Get）数据等进行检测过滤等）,跨站脚本攻击（XSS）、SQL注入攻击等恶意攻击")]
    public partial class SafeUtils
    {

        //正则过滤字符
        private const string StrRegex = @"<[^>]+?style=[w]+?:expression(|(alert|confirm|prompt)|^+/v(8|9)|<[^>]*?=[^>]*?&#[^>]*?>|(and|or).{1,6}?(=|>|<|in|like)|/*.+?*/|<s*script|<s*img|EXEC|UNION.+?SELECT|UPDATE.+?SET|INSERTs+INTO.+?VALUES|(SELECT|DELETE).+?FROM|(CREATE|ALTER|DROP|TRUNCATE)s+(TABLE|DATABASE)";
       
        /// <summary>
        ///  POST请求
        /// </summary>
        /// <param name="putData">输出非法字符串</param>
        /// <returns></returns>
        public static bool PostData(out string putData)
        {
            bool result = false;
            putData = string.Empty;
            for (int i = 0; i < HttpContext.Current.Request.Form.Count; i++)
            {
                result = CheckData(HttpContext.Current.Request.Form[i].ToString(), out putData);
                if (result)
                {
                    putData = HttpContext.Current.Request.Form[i].ToString();
                    break;
                }
            }
            return result;
        }


        /// <summary>
        /// GET请求
        /// </summary>
        /// <param name="putData">输出非法字符串</param>
        /// <returns></returns>
        public static bool GetData(out string putData)
        {
            bool result = false;
            putData = string.Empty;
            for (int i = 0; i < HttpContext.Current.Request.QueryString.Count; i++)
            {
                result = CheckData(HttpContext.Current.Request.QueryString[i].ToString(), out putData);
                if (result)
                {
                    putData = HttpContext.Current.Request.QueryString[i].ToString();
                    break;
                }
            }
            return result;
        }

        /// <summary>
        /// COOKIE数据
        /// </summary>
        /// <param name="putData">输出非法字符串</param>
        /// <returns></returns>
        public static bool CookieData(out string putData)
        {
            bool result = false;
            putData = string.Empty;
            for (int i = 0; i < HttpContext.Current.Request.Cookies.Count; i++)
            {
                result = CheckData(HttpContext.Current.Request.Cookies[i].Value.ToLower(), out putData);
                if (result)
                {
                    putData = HttpContext.Current.Request.Cookies[i].Value.ToLower();
                    break;
                }
            }
            return result;

        }


        /// <summary>
        /// UrlReferrer请求来源
        /// </summary>
        /// <param name="putData">输出非法字符串</param>
        /// <returns></returns>
        public static bool Referer(out string putData)
        {
            bool result = false;
            result = CheckData(HttpContext.Current.Request.UrlReferrer.ToString(), out putData);
            if (result)
            {
                putData = HttpContext.Current.Request.UrlReferrer.ToString();
            }
            return result;
        }


        /// <summary>
        /// 正则检查
        /// </summary>
        /// <param name="inputData">字符串</param>
        /// <param name="putData">输出非法字符串</param>
        /// <returns></returns>
        public static bool CheckData(string inputData, out string putData)
        {
            putData = string.Empty;
            //if (Regex.IsMatch(inputData.ToUpper(), StrRegex.ToUpper(),RegexOptions.IgnoreCase))
            if (Regex.IsMatch(inputData, StrRegex, RegexOptions.IgnoreCase))  //忽略大小写
            {
                putData = inputData;
                return true;
            }
            else
            {
                return false;
            }
        }
    

    }