[研究]ASP.NET, WebForm, MasterPage, 跨站請求偽造 XSRF/CSRF(Cross-Site Request Forgery)防護
2025-06-24
環境:Visual Studio 2022 + ASP.NET + WebForm + Web Application + C# + SQL Server 2019 + SQL Server Management Studio (SSMS) 19
********************************************************************************
Site1.master
<%@ Master Language="C#" AutoEventWireup="true" CodeBehind="Site1.master.cs"
Inherits="WebApplication1.Site1" %>
<!DOCTYPE html>
<html>
<head runat="server">
<meta http-equiv="Content-Type" content="text/html; charset=utf-8"/>
<title></title>
<asp:ContentPlaceHolder ID="head" runat="server">
</asp:ContentPlaceHolder>
</head>
<body>
<form id="form1" runat="server">
<asp:HiddenField ID="AntiCsrfToken" runat="server" />
<asp:ContentPlaceHolder ID="ContentPlaceHolder1" runat="server">
</asp:ContentPlaceHolder>
</form>
</body>
</html>
|
Site1.master.cs
using System;
using System.Collections.Generic;
using System.Linq;
using System.Web;
using System.Web.Security;
using System.Web.UI;
using System.Web.UI.WebControls;
namespace WebApplication1
{
public partial class Site1 : System.Web.UI.MasterPage
{
private const string AntiXsrfTokenKey = "__AntiXsrfToken";
private const string AntiXsrfUserNameKey = "__AntiXsrfUserName";
private string _antiXsrfTokenValue;
protected void Page_Init(object sender, EventArgs e)
{
// The code below helps to protect against XSRF attacks
var requestCookie = Request.Cookies[AntiXsrfTokenKey];
if (requestCookie != null && Guid.TryParse(requestCookie.Value, out Guid requestCookieGuidValue))
{
// Use the Anti-XSRF token from the cookie
_antiXsrfTokenValue = requestCookie.Value;
Page.ViewStateUserKey = _antiXsrfTokenValue;
}
else
{
// Generate a new Anti-XSRF token and save to the cookie
_antiXsrfTokenValue = Guid.NewGuid().ToString("N");
Page.ViewStateUserKey = _antiXsrfTokenValue;
var responseCookie = new HttpCookie(AntiXsrfTokenKey)
{
HttpOnly = true,
Value = _antiXsrfTokenValue
};
if (FormsAuthentication.RequireSSL && Request.IsSecureConnection)
{
responseCookie.Secure = true;
}
Response.Cookies.Set(responseCookie);
}
Page.PreLoad += master_Page_PreLoad;
}
protected void master_Page_PreLoad(object sender, EventArgs e)
{
if (!IsPostBack)
{
// Set Anti-XSRF token
ViewState[AntiXsrfTokenKey] = Page.ViewStateUserKey;
ViewState[AntiXsrfUserNameKey] = Context.User.Identity.Name ?? string.Empty;
}
else
{
// Validate the Anti-XSRF token
if ((string)ViewState[AntiXsrfTokenKey] != _antiXsrfTokenValue
|| (string)ViewState[AntiXsrfUserNameKey] != (Context.User.Identity.Name ?? string.Empty))
{
throw new InvalidOperationException("Validation of Anti-XSRF token failed.");
}
}
}
protected void Page_Load(object sender, EventArgs e)
{
}
}
}
|
Default.aspx
<%@ Page Title="" Language="C#" MasterPageFile="~/Site1.Master" AutoEventWireup="true"
CodeBehind="Default.aspx.cs" Inherits="WebApplication1.Default" %>
<asp:Content ID="Content1" ContentPlaceHolderID="head" runat="server">
</asp:Content>
<asp:Content ID="Content2" ContentPlaceHolderID="ContentPlaceHolder1" runat="server">
<asp:Button ID="Button1" runat="server" Text="Button" OnClick="Button1_Click" />
</asp:Content>
|
Default.aspx.cs
using System;
namespace WebApplication1
{
public partial class Default : System.Web.UI.Page
{
protected void Page_Load(object sender, EventArgs e)
{
}
protected void Button1_Click(object sender, EventArgs e)
{
Response.Write("XSRF (CSRF) 測試範例!");
}
}
}
|
用 OWASP Zed Attack Proxy (ZAP) 2.16.1 (2025-03-26 釋出) 測試
(完)
相關

沒有留言:
張貼留言