Cannot retrieve cookie

Question

Using FormsAuthentication, I am creating a FormsAuthenticationTicket, encrypting, adding this to a cookie using Response.Cookies.Add(authCookie). I then do a redirect using Response.Redirect to the original page that was requested. There is code in the Global.asax in the Application_AuthenticateRequest method that looks to retrieve the cookie - HttpCookie authCookie = Context.Request.Cookies[cookieName]. For some reason, however, when it hits the Global.asax code after the redirect is called, there are no cookies in the collection. At this point, I am a bit stumped as to why it is losing the cookie from the collection. Any thoughts as to why this would happen? Right now, I am just working within localhost.

Login Page Code:

    string adPath = "LDAP://ldapserveraddress";

    LdapAuthentication adAuth = new LdapAuthentication(adPath);
    try
    {
        if (true == adAuth.IsAuthenticated("ES", txtUsername.Text, txtPassword.Text))
        {
            string groups = adAuth.GetGroups();


            //Create the ticket, and add the groups.
            bool isCookiePersistent = chkPersist.Checked;
            FormsAuthenticationTicket authTicket = new FormsAuthenticationTicket(1,
                      txtUsername.Text, DateTime.Now, DateTime.Now.AddMinutes(60), isCookiePersistent, groups);

            //Encrypt the ticket.
            string encryptedTicket = FormsAuthentication.Encrypt(authTicket);

            //Create a cookie, and then add the encrypted ticket to the cookie as data.
            HttpCookie authCookie = new HttpCookie(FormsAuthentication.FormsCookieName, encryptedTicket);

            if (true == isCookiePersistent)
                authCookie.Expires = authTicket.Expiration;

            //Add the cookie to the outgoing cookies collection.
            Response.Cookies.Add(authCookie);

            string redirect = FormsAuthentication.GetRedirectUrl(txtUsername.Text, false);
            //You can redirect now.
            Response.Redirect(redirect,false);
        }
        else
        {
            errorLabel.Text = "Authentication did not succeed. Check user name and password.";
        }
    }
    catch (Exception ex)
    {
        errorLabel.Text = "Error authenticating. " + ex.Message;
    }
}

Global.asax Code (Application_AuthenticateRequest):

    string cookieName = FormsAuthentication.FormsCookieName;
    HttpCookie authCookie = Context.Request.Cookies[cookieName];

    if (null == authCookie)
    {
        //There is no authentication cookie.
        return;
    }
    FormsAuthenticationTicket authTicket = null;
    try
    {
        authTicket = FormsAuthentication.Decrypt(authCookie.Value);
    }
    catch (Exception ex)
    {
        //Write the exception to the Event Log.
        return;
    }
    if (null == authTicket)
    {
        //Cookie failed to decrypt.
        return;
    }
    //When the ticket was created, the UserData property was assigned a
    //pipe-delimited string of group names.
    string[] groups = authTicket.UserData.Split(new char[] { '|' });
    //Create an Identity.
    GenericIdentity id = new GenericIdentity(authTicket.Name, "LdapAuthentication");
    //This principal flows throughout the request.
    GenericPrincipal principal = new GenericPrincipal(id, groups);
    Context.User = principal;
}`

Are you redirecting to a url that belongs to a different domain and setting a domain cookie. — Saravanan
The redirect is simply to the originally requested page. In this case, it was to Default.aspx. In the address bar when it redirects to the Login page, it shows: localhost:64432/Login?ReturnUrl=%2fDefault.aspx — Todd Zetlan

Todd Zetlan Todd Zetlan · Accepted Answer · 2014-01-24T02:47:43

I was able to resolve my issue by adjusting the data that was being stored in the userData of the FormsAuthenticationTicket. It appears as though the amount of data that I was trying to insert exceeded a maximum. Once I removed, everything works as expected.

Cannot retrieve cookie

1 Answers