在Global.asax文件里实现通用防SQL注入漏洞程序(适应于post/get请求)

时间:2022-09-17 22:43:00

首先,创建一个SQLInjectionHelper类完成恶意代码的检查 
代码如下: 

复制代码代码如下:


using System; 
using System.Collections.Generic; 
using System.Linq; 
using System.Web; 
using System.Text.RegularExpressions; 
/// <summary> 
///SQLInjectionHelper 的摘要说明 
/// </summary> 
public class SQLInjectionHelper 

/// <summary> 
/// 获取Post的数据 
/// </summary> 
/// <param name="request"></param> 
/// <returns></returns> 
public static bool ValidUrlData(string request) 

bool result = false; 
if (request == "POST") 

for (int i = 0; i < HttpContext.Current.Request.Form.Count; i++) 

result = ValidData(HttpContext.Current.Request.Form[i].ToString()); 
if (result) 

break; 



else 

for (int i = 0; i < HttpContext.Current.Request.QueryString.Count; i++) 

result = ValidData(HttpContext.Current.Request.QueryString[i].ToString()); 
if (result) 

break; 



return result; 

/// <summary> 
/// 验证是否存在注入代码 
/// </summary> 
/// <param name="inputData"></param> 
/// <returns></returns> 
private static bool ValidData(string inputData) 

//验证inputData是否包含恶意集合 
if (Regex.IsMatch(inputData, GetRegexString())) 

return true; 

else 

return false; 


/// <summary> 
/// 获取正则表达式 
/// </summary> 
/// <returns></returns> 
private static string GetRegexString() 

//构造SQL的注入关键字符 
string[] strChar = { "and", "exec", "insert", "select", "update", "delete", "count", "from", "drop", "asc", "or", "char", "%", ";", ":", "\'", "\"", "-", "chr", "master", "mid", "truncate", "declare", "char", "SiteName", "/add", "xp_cmdshell", "net user", "net localgroup administrators", "exec master.dbo.xp_cmdshell" }; 
string str_Regex = ".*("; 
for (int i = 0; i < strChar.Length - 1; i++) 

str_Regex += strChar[i] + "|"; 

str_Regex += strChar[strChar.Length - 1] + ").*"; 
return str_Regex; 


有此类后即可使用Global.asax中的Application_BeginRequest(object sender, EventArgs e)事件来实现表单或者URL提交数据的获取,获取后传给SQLInjectionHelper类ValidUrlData方法来完成检查 
代码如下 

复制代码代码如下:


protected void Application_BeginRequest(object sender, EventArgs e) 

bool result = false; 
result = SQLInjectionHelper.ValidUrlData(Request.RequestType.ToUpper()); 
if (result) 

Response.Write("您提交的数据有恶意字符"); 
Response.End(); 


下面以一个小程序测试: 
创建一个页面,如下 

复制代码代码如下:


<%@ Page Language="C#" AutoEventWireup="true" CodeFile="Default.aspx.cs" Inherits="_Default" %> 
<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd"> 
<html xmlns="http://www.w3.org/1999/xhtml"> 
<head runat="server"> 
<title></title> 
</head> 
<body> 
<form id="form1" runat="server"> 
<div> 
<asp:TextBox ID="TextBox1" runat="server"></asp:TextBox> 
<br /> 
<asp:Button ID="btnPost" runat="server" Text="获取Post数据" 
onclick="btnPost_Click" /> 
</div> 
<asp:Button ID="btnGet" runat="server" Text="获取Get数据" onclick="btnGet_Click" /> 
</form> 
</body> 
</html> 


分别添加单击事件,如下 

复制代码代码如下:


protected void btnPost_Click(object sender, EventArgs e) 


protected void btnGet_Click(object sender, EventArgs e) 

Response.Redirect("Default.aspx?a=1&b=2&c=3"); 


在文本框中输入非法字符串,无论post请求还是get请求,都会被防SQL注入程序所截获

在Global.asax文件里实现通用防SQL注入漏洞程序(适应于post/get请求)

                      图1 测试防SQL注入程序的页面

在Global.asax文件里实现通用防SQL注入漏洞程序(适应于post/get请求)

                               图2 错误信息