asp.net防sql注入代码

代码如下

复制代码

web.config文件调用
    <httpHandlers>
      <add verb="*" path="*.aspx" validate="false" type="SqlIn.SqlInPost"/>
    </httpHandlers>
</system.web>

SqlInPost.cs 放到app_code 目录下：

SqlInPost.cs
using System;
using System.Data;
using System.Configuration;
using System.Web;
using System.Web.Security;
using System.Web.UI;
using System.Web.UI.WebControls;
using System.Web.UI.WebControls.WebParts;
using System.Web.UI.HtmlControls;
using System.Text.RegularExpressions;
using System.Collections.Specialized;
namespace SqlIn
{
    /// <summary>
    /// SqlInPost 的摘要说明
    /// </summary>
    public class SqlInPost:IHttpHandlerFactory
    {
        public SqlInPost()
        {
            //
            // TODO: 在此处添加构造函数逻辑
            //
        }
        public virtual IHttpHandler GetHandler(HttpContext context, string requestType, string url, string pathTranslated)
        {
            //得到编译实例(通过反射)
            PageHandlerFactory factory = (PageHandlerFactory)Activator.CreateInstance(typeof(PageHandlerFactory), true);
            IHttpHandler handler = factory.GetHandler(context, requestType, url, pathTranslated);
            //过滤字符串
            if (requestType == "POST")
            {
                Page page = handler as Page;
                if (page != null)
                    page.PreLoad += new EventHandler(FilterStrFactoryHandler_PreLoad);
            }
            if (requestType == "GET")
            {
                Page page = handler as Page;
                if (page != null)
                    page.PreLoad += new EventHandler(FilterStrFactoryHandler_PreLoad1);
            }
            //返回
            return handler;
        }
        //过滤TextBox、Input和Textarea中的特殊字符
        void FilterStrFactoryHandler_PreLoad(object sender, EventArgs e)
        {
            try
            {
                Page page = sender as Page;
                NameValueCollection postData = page.Request.Form;
                foreach (string postKey in postData)
                {
                    Control ctl = page.FindControl(postKey);
                    if (ctl as TextBox != null)
                    {
                        ((TextBox)ctl).Text = Common.InputText(((TextBox)ctl).Text);
                        continue;
                    }
                    if (ctl as HtmlInputControl != null)
                    {
                        ((HtmlInputControl)ctl).Value = Common.InputText(((HtmlInputControl)ctl).Value);
                        continue;
                    }
                    if (ctl as HtmlTextArea != null)
                    {
                        ((HtmlTextArea)ctl).Value = Common.InputText(((HtmlTextArea)ctl).Value);
                        continue;
                    }
                }
            }
            catch { }
        }
        //过滤QueryString
        void FilterStrFactoryHandler_PreLoad1(object sender, EventArgs e)
        {
            try
            {
                Page page = sender as Page;
                NameValueCollection QueryNV = page.Request.QueryString;
                bool isSafe = true;
                for (int i = 0; i < QueryNV.Count; i++)
                {
                    if (!IsSafeString(QueryNV.Get(i)))
                    {
                        isSafe = false;
                        break;
                    }
                }
                if (!isSafe)
                {
                    page.Response.Write("非法传值!");
                    page.Response.End();
                }
            }
            catch { }
        }
        public virtual void ReleaseHandler(IHttpHandler handler)
        {
        }
        //判断是否为安全字符串
        public bool IsSafeString(string p)
        {
            bool ret = true;
            string[] UnSafeArray = new string[22];
            UnSafeArray[0] = "'";
            UnSafeArray[1] = "xp_cmdshell";
            UnSafeArray[2] = "exec master.dbo.xp_cmdshell";
            UnSafeArray[3] = "net localgroup administrators";
            UnSafeArray[4] = "delete from";
            UnSafeArray[5] = "net user";
            UnSafeArray[6] = "/add";
            UnSafeArray[7] = "drop table";
            UnSafeArray[8] = "update ";
            UnSafeArray[9] = "select";
            UnSafeArray[10] = ";and";
            UnSafeArray[11] = ";exec";
            UnSafeArray[12] = ";create";
            UnSafeArray[13] = ";insert";
            UnSafeArray[14] = "and";
            UnSafeArray[15] = "exec";
            UnSafeArray[16] = "create";
            UnSafeArray[17] = "insert";
            UnSafeArray[18] = "master.dbo";
            UnSafeArray[19] = ";--";
            UnSafeArray[20] = "--";
            UnSafeArray[21] = "1=";
            foreach (string s in UnSafeArray)
            {
                if (p.ToLower().IndexOf(s) > -1)
                {
                    ret = false;
                    break;
                }
            }
            return ret;
        }
    }
    public class Common
    {
        public static string InputText(string text)
        {
            text = text.Trim();
            if (string.IsNullOrEmpty(text))
                return string.Empty;
            text = Regex.Replace(text, "[\s]{2,}", " ");    //two or more spaces
            text = Regex.Replace(text, "(<[b|B][r|R]/*>)+|(<[p|P](.|\n)*?>)", "n");    //<br>
            text = Regex.Replace(text, "(\s*&[n|N][b|B][s|S][p|P];\s*)+", " ");    //
            text = Regex.Replace(text, "<(.|\n)*?>", string.Empty);    //any other tags
            text = text.Replace("'", "''");
            text = text.Replace("xp_cmdshell", "");
            text = text.Replace("exec master.dbo.xp_cmdshell", "");
            text = text.Replace("net localgroup administrators", "");
            text = text.Replace("delete from", "");
            text = text.Replace("net user", "");
            text = text.Replace("/add", "");
            text = text.Replace("drop table", "");
            text = text.Replace("update", "");
            return text;
        }
    }
}

实例二

代码如下

复制代码

在网站里新建Global.asax，添加
void Application_BeginRequest(object source, EventArgs e)
    {
        COMP.ProcessRequest pr = new COMP.ProcessRequest();
        pr.StartProcessRequest();
    }

comp里面有文件ProcessRequest.cs代码如下 public class ProcessRequest
    {
        SQL注入式攻击代码分析#region SQL注入式攻击代码分析
        /**//// <summary>
        /// 处理用户提交的请求
        /// </summary>
        public void StartProcessRequest()
        {
            try
            {
                string getkeys = "";
                string sqlErrorPage = "/";
                if (System.Web.HttpContext.Current.Request.QueryString != null)
                {

                    for (int i = 0; i < System.Web.HttpContext.Current.Request.QueryString.Count; i++)
                    {
                        getkeys = System.Web.HttpContext.Current.Request.QueryString.Keys[i];
                        if (!ProcessSqlStr(System.Web.HttpContext.Current.Request.QueryString[getkeys].ToLower()))
                        {
                            System.Web.HttpContext.Current.Response.Redirect(sqlErrorPage);
                            System.Web.HttpContext.Current.Response.End();
                        }
                    }
                }

                //if (System.Web.HttpContext.Current.Request.Form != null)
                //{
                //    for(int i=0;i<System.Web.HttpContext.Current.Request.Form.Count;i++)
                //    {
                //        getkeys = System.Web.HttpContext.Current.Request.Form.Keys[i];
                //        if (!ProcessSqlStr(System.Web.HttpContext.Current.Request.Form[getkeys].ToLower()))
                //        {
                //            System.Web.HttpContext.Current.Response.Redirect (sqlErrorPage);
                //            System.Web.HttpContext.Current.Response.End();
                //        }
                //    }
                //}

            }
            catch
            {
                // 错误处理: 处理用户提交信息!
            }
        }
        /**//// <summary>
        /// 分析用户请求是否正常
        /// </summary>
        /// <param name="Str">传入用户提交数据</param>
        /// <returns>返回是否含有SQL注入式攻击代码</returns>
        private bool ProcessSqlStr(string Str)
        {
            bool ReturnValue = true;
            try
            {
                if (Str != "" && Str != null)
                {
                    string SqlStr = "";
                    if (SqlStr == "" || SqlStr == null)
                    {
                        SqlStr = "'|and|exec|insert|select|delete|update|count|*|chr|mid|master|truncate|char|declare";
                    }
                    string[] anySqlStr = SqlStr.Split('|');
                    foreach (string ss in anySqlStr)
                    {
                        if (Str.IndexOf(ss) >= 0)
                        {
                            ReturnValue = false;
                        }
                    }
                }
            }
            catch
            {
                ReturnValue = false;
            }
            return ReturnValue;
        }
        #endregion
    }

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