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 = ; 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 = ; 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 = ; i < strBadChar.Length - ; i++)
{
str_Regex += strBadChar[i] + "|";
}
str_Regex += strBadChar[strBadChar.Length - ] + ").*"; 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) != -)
{
//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
}
}
SQLInjectionHelper