C#工具:防sql注入帮助类

SQL注入是比较常见的网络攻击方式之一,它不是利用操作系统的BUG来实现攻击,而是针对程序员编程时的疏忽,通过SQL语句,实现无帐号登录,甚至篡改数据库。

using System;using System.Collections.Generic;using System.Text;using System.Web;using System.Text.RegularExpressions;namespace Core.Common{ /// <summary> /// SQL注入帮助 /// </summary> public class SQLInjectionHelper { private const string StrKeyWord = @".*(select|insert|delete|from|count(|drop table|update|truncate|asc(|mid(|char(|xp_cmdshell|exec master|netlocalgroup administrators|:|net user|""|or|and).*"; private const string StrRegex = @"[-|;|,|/|(|)|[|]|}|{|%|@|*|!|‘]"; /// <summary> /// 获取Post的数据 /// </summary> public static bool ValidUrlPostData() { bool result = false; for (int i = 0; i < HttpContext.Current.Request.Form.Count; i++) { result = ValidData(HttpContext.Current.Request.Form[i].ToString()); if (result) { LogHelper.Info("检测出POST恶意数据: 【" + HttpContext.Current.Request.Form[i].ToString() + "】 URL: 【" + HttpContext.Current.Request.RawUrl + "】来源: 【" + HttpContext.Current.Request.UserHostAddress + ""); break; }//如果检测存在漏洞 } return result; } /// <summary> /// 获取QueryString中的数据 /// </summary> public static bool ValidUrlGetData() { bool result = false; for (int i = 0; i < HttpContext.Current.Request.QueryString.Count; i++) { result = ValidData(HttpContext.Current.Request.QueryString[i].ToString()); if (result) { LogHelper.Info("检测出GET恶意数据: 【" + HttpContext.Current.Request.QueryString[i].ToString() + "】 URL: 【" + HttpContext.Current.Request.RawUrl + "】来源: 【" + HttpContext.Current.Request.UserHostAddress + ""); break; }//如果检测存在漏洞 } return result; } /// <summary> /// 验证是否存在注入代码 /// </summary> /// <param name="inputData"></param> public static bool ValidData(string inputData) { //里面定义恶意字符集合 //验证inputData是否包含恶意集合 if (Regex.IsMatch(inputData.ToLower(), GetRegexString())) { return true; } else { return false; } } /// <summary> /// 获取正则表达式 /// </summary> /// <param name="queryConditions"></param> /// <returns></returns> private static string GetRegexString() { //构造SQL的注入关键字符 string[] strBadChar = { "and" ,"exec" ,"insert" ,"select" ,"delete" ,"update" ,"count" ,"from" ,"drop" ,"asc" ,"char" ,"or" ,"%" ,";" ,":" ,"\‘" ,"\"" ,"-" ,"chr" ,"mid" ,"master" ,"truncate" ,"char" ,"declare" ,"SiteName" ,"net user" ,"xp_cmdshell" ,"/add" ,"exec master.dbo.xp_cmdshell" ,"net localgroup administrators" }; //构造正则表达式 string str_Regex = ".*("; for (int i = 0; i < strBadChar.Length - 1; i++) { str_Regex += strBadChar[i] + "|"; } str_Regex += strBadChar[strBadChar.Length - 1] + ").*"; return str_Regex; } /// <summary> /// 检测是否有Sql危险字符 /// </summary> /// <param name="str">要判断字符串</param> /// <returns>判断结果</returns> public static bool IsSafeSqlString(string str) { return !Regex.IsMatch(str, @"[-|;|,|\/|\(|\)|\[|\]|\}|\{|%|@|\*|!|\‘]"); } /// <summary> SQL注入等安全验证 /// 检测是否有危险的可能用于链接的字符串 /// </summary> /// <param name="str">要判断字符串</param> /// <returns>判断结果</returns> public static bool IsSafeUserInfoString(string str) { return !Regex.IsMatch(str, @"^\s*$|^c:\\con\\con$|[%,\*" + "\"" + @"\s\t\<\>\&]|游客|^Guest"); } #region 检测客户的输入中是否有危险字符串 /// <summary> /// 检测客户输入的字符串是否有效,并将原始字符串修改为有效字符串或空字符串。 /// 当检测到客户的输入中有攻击性危险字符串,则返回false,有效返回true。 /// </summary> /// <param name="input">要检测的字符串</param> public static bool IsValidInput(ref string input) { try { //替换单引号 input = input.Replace("", "‘‘").Trim(); //检测攻击性危险字符串 string testString = "and |or |exec |insert |select |delete |update |count |chr |mid |master |truncate |char |declare "; string[] testArray = testString.Split(|); foreach (string testStr in testArray) { if (input.ToLower().IndexOf(testStr) != -1) { //检测到攻击字符串,清空传入的值 input = ""; return false; } } //未检测到攻击字符串 return true; } catch (Exception ex) { throw new Exception(ex.Message); } } #endregion }}

 

相关文章