真的对sql注入感到困惑

Question

获得了有关可能导致SQL注入的错误的详细页面

URL编码的GET输入classid设置为1 AND 3 * 2 * 1 = 6 AND 608 = 608

进行的测试：

• 1 * 1 * 1 * 1 =>是
• 1 * 608 * 603 * 0 =>假
• 11 * 5 * 2 * 999 =>假
• 1 * 1 * 1 =>是
• 1 * 1 * 1 * 1 * 1 * 1 =>是
• 11 * 1 * 1 * 0 * 1 * 1 * 608 =>假
• 1 AND 5 * 4 = 20 AND 608 = 608 => TRUE
• 1 AND 5 * 4 = 21 AND 608 = 608 => FALSE ...（行被截断）

这是可能导致此问题的源代码：

if (!string.IsNullOrEmpty(Request.QueryString["classid"]))
{
    string tSql = @" SELECT  [Award_ID],[Award_Name],[Award_Info],[Award_Pic],[Award_Num],[Award_MoneyCost],[Award_MoneyGet],[Award_Type],[Award_AddDate],[Award_Hot],[Award_OnLineTime],[AwardProP],[PrizeSlidePic],[PrizeDetailPic],[PrizeBigSlidePic],[IsTop],[ClassID] FROM  dbo.Web_Award WHERE ClassID={0} ";

    DataTable data = DbSession.Default.FromSql(string.Format(tSql, Request.QueryString["classid"])).ToDataTable();

    if (data.Rows.Count > 0)
    {
        rptList.DataSource = data;
        rptList.DataBind();
    }
}
else
{
    string tSql = @" SELECT  [Award_ID],[Award_Name],[Award_Info],[Award_Pic],[Award_Num],[Award_MoneyCost],[Award_MoneyGet],[Award_Type],[Award_AddDate],[Award_Hot],[Award_OnLineTime],[AwardProP],[PrizeSlidePic],[PrizeDetailPic],[PrizeBigSlidePic],[IsTop],[ClassID] FROM  dbo.Web_Award  ";

    DataTable data = DbSession.Default.FromSql(tSql).ToDataTable();

    if (data.Rows.Count > 0)
    {
        rptList.DataSource = data;
        rptList.DataBind();
    }
}

谁能告诉我该如何处理...非常感谢！

现在我修改了我的代码

if (!string.IsNullOrEmpty(Request.QueryString["classid"]))
        {
            //string tSql = @" SELECT  [Award_ID],[Award_Name],[Award_Info],[Award_Pic],[Award_Num],[Award_MoneyCost],[Award_MoneyGet],[Award_Type],[Award_AddDate],[Award_Hot],[Award_OnLineTime],[AwardProP],[PrizeSlidePic],[PrizeDetailPic],[PrizeBigSlidePic],[IsTop],[ClassID] FROM  dbo.Web_Award WHERE ClassID={0} ";
            string tSql = "SELECT [Award_ID],[Award_Name],[Award_Info],[Award_Pic],[Award_Num],[Award_MoneyCost],[Award_MoneyGet],[Award_Type],[Award_AddDate],[Award_Hot],[Award_OnLineTime],[AwardProP],[PrizeSlidePic],[PrizeDetailPic],[PrizeBigSlidePic],[IsTop],[ClassID] FROM dbo.Web_Award WHERE ClassID = @ClassID";
            //DataTable data = DbSession.Default.FromSql(string.Format(tSql, Request.QueryString["classid"])).ToDataTable();
            SqlConnection connection = new SqlConnection("Server=(local);Integrated Security=SSPI;database=DaysQP");
            connection.Open();
            SqlCommand command = new SqlCommand(tSql, connection);
            command.Parameters.Add(new SqlParameter("@ClassId", System.Data.SqlDbType.Int));
            command.Parameters["@ClassID"].Value = 1;
            using (SqlDataReader dr = command.ExecuteReader())
            {
                var data = new DataTable();
                data.Load(dr);
                if (data.Rows.Count > 0)
                {
                    rptList.DataSource = data;
                    rptList.DataBind();
                }
            }
            connection.Close();
        }
        else
        {
            string tSql = @" SELECT  [Award_ID],[Award_Name],[Award_Info],[Award_Pic],[Award_Num],[Award_MoneyCost],[Award_MoneyGet],[Award_Type],[Award_AddDate],[Award_Hot],[Award_OnLineTime],[AwardProP],[PrizeSlidePic],[PrizeDetailPic],[PrizeBigSlidePic],[IsTop],[ClassID] FROM  dbo.Web_Award  ";
            DataTable data = DbSession.Default.FromSql(tSql).ToDataTable();
            if (data.Rows.Count > 0)
            {
                rptList.DataSource = data;
                rptList.DataBind();
            }
        }

但是问题仍然存在。

最后使用参数化查询解决了这个问题！

if (!string.IsNullOrEmpty(Request.QueryString["classid"]))
{   
    int number;
    bool result = Int32.TryParse(Request.QueryString["classid"], out number);

if (result == false)
{
    return;
}

//string tSql = @" SELECT  [Award_ID],[Award_Name],[Award_Info],[Award_Pic],[Award_Num],[Award_MoneyCost],[Award_MoneyGet],[Award_Type],[Award_AddDate],[Award_Hot],[Award_OnLineTime],[AwardProP],[PrizeSlidePic],[PrizeDetailPic],[PrizeBigSlidePic],[IsTop],[ClassID] FROM  dbo.Web_Award WHERE ClassID={0} ";
string tSql = "SELECT [Award_ID],[Award_Name],[Award_Info],[Award_Pic],[Award_Num],[Award_MoneyCost],[Award_MoneyGet],[Award_Type],[Award_AddDate],[Award_Hot],[Award_OnLineTime],[AwardProP],[PrizeSlidePic],[PrizeDetailPic],[PrizeBigSlidePic],[IsTop],[ClassID] FROM dbo.Web_Award WHERE ClassID = @ClassID";
 //DataTable data = DbSession.Default.FromSql(string.Format(tSql, Request.QueryString["classid"])).ToDataTable();

SqlConnection connection = (SqlConnection)DbSession.Default.CreateConnection();
//SqlConnection("Server=(local);Integrated Security=SSPI;database=DaysQP");
connection.Open();
SqlCommand command = new SqlCommand(tSql, connection);
command.Parameters.Add(new SqlParameter("@ClassId", System.Data.SqlDbType.Int));
command.Parameters["@ClassID"].Value = number;
using (SqlDataReader dr = command.ExecuteReader())
{
    var data = new DataTable();
    data.Load(dr);
    if (data.Rows.Count > 0)
    {
        rptList.DataSource = data;
        rptList.DataBind();
    }
}
connection.Close();

}

Answer 1

注射的潜力将在这里：

string tSql = @" SELECT  [Award_ID],[Award_Name],[Award_Info],[Award_Pic],[Award_Num],[Award_MoneyCost],[Award_MoneyGet],[Award_Type],[Award_AddDate],[Award_Hot],[Award_OnLineTime],[AwardProP],[PrizeSlidePic],[PrizeDetailPic],[PrizeBigSlidePic],[IsTop],[ClassID] FROM  dbo.Web_Award WHERE ClassID={0} ";
DataTable data = DbSession.Default.FromSql(string.Format(tSql, Request.QueryString["classid"])).ToDataTable();

您期望查询返回其classId与Request.QueryString["classid"]匹配的Web_Award表记录

如果Request.QueryString["classid"]值类似于：

1 or 1=1

然后查询变为：

select award_id,..... from web_awards where classId=1 or 1=1

最终您将返回原本不希望的数据。

从本质上讲，这是sql注入，您可能已阅读了更多有关它。 使用存储过程或参数化查询可防止此类攻击。