Anti forgery token on login page
I've written up a full solution here: https://richardcooke.info/en/2014/keep-users-signed-in-after-asp-net-deploy/
Here's the necessary code to call in your controller form your GET method:
private void SetANewRequestVerificationTokenManuallyInCookieAndOnTheForm()
{
if (Response == null)
return;
string cookieToken, formToken;
AntiForgery.GetTokens(null, out cookieToken, out formToken);
SetCookie("__RequestVerificationToken", cookieToken);
ViewBag.FormToken = formToken;
}
private void SetCookie(string name, string value)
{
if (Response.Cookies.AllKeys.Contains(name))
Response.Cookies[name].Value = value;
else
Response.Cookies.Add(new HttpCookie(name, value));
}
and code to put in your view in place of Html.AntiForgeryToken():
@if (ViewBag.FormToken != null)
{
<text><input name="__RequestVerificationToken" type="hidden" value="@ViewBag.FormToken" /></text>
}
else
{
<text>@Html.AntiForgeryToken()</text>
}
Don't implement the ASP.NET AntiForgeryToken on your login page. The token is based on a username among other criteria and a login page assume the attacker already has credentials to a system in order to be able to exploit csrf on that page.
However, you should use some form of CSRF protection on your login page - see https://security.stackexchange.com/a/2126/51772