How do I implement password reset with ASP.NET Identity for ASP.NET MVC 5.0?

Question

Microsoft is coming up with a new Membership system called ASP.NET Identity (also the default in ASP.NET MVC 5). I found the sample project, but this is not implemented a password reset.

On password reset topic just found this Article: Implementing User Confirmation and Password Reset with One ASP.NET Identity – Pain or Pleasure, not help for me, because do not use the built-in password recovery.

As I was looking at the options, as I think we need to generate a reset token, which I will send to the user. The user can set then the new password using the token, overwriting the old one.

I found the IdentityManager.Passwords.GenerateResetPasswordToken / IdentityManager.Passwords.GenerateResetPasswordTokenAsync(string tokenId, string userName, validUntilUtc), but I could not figure out what it might mean the tokenId parameter.

How do I implement the Password Reset in ASP.NET with MVC 5.0?

Solution 1

I get it: The tokenid is a freely chosen identity, which identifies a password option. For example,

1. looks like the password recovery process, step 1 (it is based on: https://stackoverflow.com/a/698879/208922)

[HttpPost]
[ValidateAntiForgeryToken]
[AllowAnonymous]
//[RecaptchaControlMvc.CaptchaValidator]
public virtual async Task<ActionResult> ResetPassword(
                                              ResetPasswordViewModel rpvm)
{
    string message = null;
    //the token is valid for one day
    var until = DateTime.Now.AddDays(1);
    //We find the user, as the token can not generate the e-mail address, 
    //but the name should be.
    var db = new Context();
    var user = db.Users.SingleOrDefault(x=>x.Email == rpvm.Email);

    var token = new StringBuilder();

    //Prepare a 10-character random text
    using (RNGCryptoServiceProvider 
                        rngCsp = new RNGCryptoServiceProvider())
    {
        var data = new byte[4];
        for (int i = 0; i < 10; i++)
        {
            //filled with an array of random numbers
            rngCsp.GetBytes(data);
            //this is converted into a character from A to Z
            var randomchar = Convert.ToChar(
                                      //produce a random number 
                                      //between 0 and 25
                                      BitConverter.ToUInt32(data, 0) % 26 
                                      //Convert.ToInt32('A')==65
                                      + 65
                             );
            token.Append(randomchar);
        }
    }
    //This will be the password change identifier 
    //that the user will be sent out
    var tokenid = token.ToString();

    if (null!=user)
    {
        //Generating a token
        var result = await IdentityManager
                                .Passwords
                                .GenerateResetPasswordTokenAsync(
                                              tokenid, 
                                              user.UserName, 
                                              until
                           );

        if (result.Success)
        {
            //send the email
            ...
        }
    }
    message = 
        "We have sent a password reset request if the email is verified.";
    return RedirectToAction(
                   MVC.Account.ResetPasswordWithToken(
                               token: string.Empty, 
                               message: message
                   )
           );
}

2 And then when the user enters the token and the new password:

[HttpPost]
[ValidateAntiForgeryToken]
[AllowAnonymous]
//[RecaptchaControlMvc.CaptchaValidator]
public virtual async Task<ActionResult> ResetPasswordWithToken(
                                            ResetPasswordWithTokenViewModel 
                                                        rpwtvm
                                        )
{
    if (ModelState.IsValid)
    {
        string message = null;
        //reset the password
        var result = await IdentityManager.Passwords.ResetPasswordAsync(
                                                   rpwtvm.Token, 
                                                   rpwtvm.Password
                           );
        if (result.Success)
        { 
            message = "the password has been reset.";
            return RedirectToAction(
                        MVC.Account.ResetPasswordCompleted(message: message)
                   );
        }
        else
        {
            AddErrors(result);
        }
    }
    return View(MVC.Account.ResetPasswordWithToken(rpwtvm));
}

Skeleton proposal to sample project on github, if anyone needs it may be tested.The E-mail sending not yet written, possibly with the addition soon.

Solution 2

Seems like a lot of trouble... What advantage does the above give over:

1. the user clicking a 'Recover Account' link
2. this sends an 64 byte encoded string of a datetime ticks value (call it psuedo-hash) in an email
3. click the link back in the email to a controller/action route that
4. matches email and it's source server to psuedo-hash, decrypts the psuedo-hash, validates the time since sent and
5. offers a View for the user to set a new password
6. with a valid password, the code removes the old user password and assigns the new.
7. Once complete, successful or not, delete the psuedo-hash.

With this flow, at no time do you EVER send a password out of your domain.

Please, anyone, prove to me how this is any less secure.