How to Prevent CSRF in Play [2.0] Using Scala? - security

A lot of web frameworks have a standard setup for generating forms with auth tokens.
Do I have to create such measures manually, or does Play come with a build in means of prevening CSRF?
The documentation on the Play website doesn't seem to address this.

I use the play2-authenticitytoken module:
The authenticity token is a way around one of the most serious internet security threats: CRSF attacks. It ensures that the client submitting a form is the one who received the page (and not a hacker who stole your session data).
How it works:
In a nutshell:
on every form post, we add a hidden parameter containing a uuid
the uuid is signed and its signature is stored in the session (which translated into a cookie)
When the user submits the form, we get: the uuid, the signature and the other form inputs.
We sign the incoming uuid again
Validation passes if the signatures match (session.sign=uuid.sign)
Should an attacker inject a different id, he will never figure how to generate the correct signature.

For completeness sake, I have an example here in Scala for Play 2.0
https://github.com/jacobgroundwater/Scala-Play-CSRF
This method also uses the cookie + hidden-field approach.
Example Usage
Use the SessionKey action to help sign a form:
object Application extends Controller {
def login = SessionKey{ (key,signature) =>
Action { implicit request =>
Ok( views.html.login(signature) ).withSession( key->signature )
}
}
}
When parsing forms use the following to check for the signature:
object Authenticator extends Controller {
def login = ValidateForm{
Action { implicit request =>
Ok( views.html.index("You're Loggd In") )
}
}
}

Since Play 2.1 there's support for this in the framework. Nick Carroll wrote a nice little article on how to use it:
http://nickcarroll.me/2013/02/11/protect-your-play-application-with-the-csrf-filter/

Related

Send additional parameters to social login

Is there anyway to save additional data to the session when doing a social login/signup?
I noticed that if I send returnUrl parameter to the SS OAuth endpoint (i.e. /auth/google?retunUrl=...) then this value gets saved to the session as ReferrerUrl so I am using that to embed data as url parameters. I would prefer to be able to write to the Meta collection when directing to the SS Auth endpoint and then later read it from the session.
I tried to follow the exact process of how this was being saved to the session but I found it quite confusing.
What is the best way to add additional meta data to a social login/signup?
Edit:
I am talking about making a GET request to /auth/google, /auth/facebook etc...
I have additional data I want to track with the signup the user has entered in the browser.
If I add code to OnAuthenticated then this doesn't solve problem as the data has gone out of scope of the browser. It has to be passed in the GET request to the auth endpoint or have some reference to match up.
Edit:
public class CustomUserSession : AuthUserSession
{
public override void OnCreated(IRequest httpReq)
{
this.Meta.Add("foo", "bar");
httpReq.SaveSession(this);
}
}
You can handle a callback with the OnAuthenticated() Session or Auth Events.

Secure payment with paypal

I am trying to implement a secure payment option with react-paypal-express-checkout...
but I saw that user can easily change the amount with chrome dev tools ... shouldn't I make the API request to paypal from my server and validate the amount with my DB? I didn't saw any option to do that with paypal...
here is my code:
import React, { Component } from 'react';
import { connect } from 'react-redux';
import 'react-credit-cards/es/styles-compiled.css'
import './checkout.css';
import PaypalExpressBtn from 'react-paypal-express-checkout';
class CheckOut extends Component {
constructor(props) {
super(props);
this.state = {
amount: 40
}
}
render() {
const client = {
sandbox: 'XXXX',
production: 'Your-Production-Client-ID',
}
return (
<PaypalExpressBtn client={client} currency={'USD'} total={this.state.amount} />
);
}
}
export default connect(CheckOut);
Paypal allows both types of uses, from the client and from the server. I guess it's possible for the client to modify the request on their end to pay less. But, in the end, whatever your business is, you'll get an order and a payment. Just check if the payment is different than it should be and don't fulfil the order, make a refund.
If you want to save the trouble, then use the server option that makes the payment through your server.
In any case, like with any other payment method, I would recommend you take the time to implement it yourself following the great and well documented API provided by Paypal. They have a lot of examples and use cases, with code for the browser and the server.
Never trust values coming from the client side. You should absolutely validate the amount on the server-side.
As #jorbuedo said, you can create a server integration so the values are never exposed client side. Send a session ID or Order Number or something to your server, retrieve the order from your DB, and perform a redirect to PayPal to process the transaction server-side.
Alternatively, you can keep the client-side stuff you have, but then validate the transaction after it's been complete. You could use Instant Payment Notifications or the newer Webhooks to do this.
You could pass a custom variable into the paymentOptions property of <PaypalExpressButton ...>, and then use this value to validate the correct amount has been paid in IPN.
For example:
<PaypalExpressButton
client={client}
currency="USD"
total={this.state.amount}
paymentOptions={{
custom: this.props.sessionId
}}
/>
Then, as part of IPN, you can pull the Session ID out the DB, check the expected payment amount (which you'll need to store, or calculate based on the items/prices saved against the session ID) is the same as the payment amount Paypal provides (mc_gross for example). A full list of variables you get as part of IPN is available here.
There are no fees for using IPN. If you didn't want to build out this flow, then you'd have to manually validate every order that's made to ensure the amount is correct. If you're running something small, this might be an acceptable compromise.
Edit: Don't just send the expected amount as the Custom variable, and compare that to the mc_gross value, as this can also be changed using F12 or a browser extension. The value needs to be something opaque that you can translate server-side into something meaningful.
#jorbuedo and #Dave Salomon give great answers about Security and you should take them in to consideration.
However, If you really don't want to user to change your Component state and props, You can disable React Devtools with this hack.
if (window.__REACT_DEVTOOLS_GLOBAL_HOOK__) {
window.__REACT_DEVTOOLS_GLOBAL_HOOK__.emit = function() {};
}
Basically it mocks some methods of react-devtools and Devtool cannot find your component tree anyway.
This answer is only for disabling user to edit your components. This is not best solution for security)

How to make two factor authentication token expire after single use

I implemented two factor authentication but by following this tutorial
https://learn.microsoft.com/en-us/aspnet/identity/overview/features-api/two-factor-authentication-using-sms-and-email-with-aspnet-identity
I want to make the code expire after single use.
Right now, user receives the same code during the expiration time (which is set to 5 minutes) completes. Is there a way to make the code single use? I couldn't find anything on this subject.
There is a note in the tutorial that you linked to that says:
The 2FA codes are generated using Time-based One-time Password Algorithm and codes are valid for six minutes. If you take more than six minutes to enter the code, you'll get an Invalid code error message.
So, using this method, you cannot make the code expire after user.
You could, as an addition, keep a store of codes that have been used and check against that store before validating the code. You could allow the codes to expire out of that store after 6 minutes, which is their natural expiry time, but in the meantime use them to reject a second authentication.
Alternatively, you can choose to avoid the TOTP method and generate a random code that you store against your user before you send the SMS or email. Then you can check against that code when the user authenticates with it and delete or invalidate the code at that point. Using TOTP means that you could extend this 2FA to use an authenticator app based flow for the authentication too, which is more secure than SMS or email.
AspNetIdentity does not automatically invalidate used second factor codes, a code is always valid for a six minute window, but there is a workaround for this.
One of the inputs to the token generator is the SecurityStamp, which is stored as part of the user account. Token providers that extend the TotpSecurityStampBasedTokenProvider, like for example the EmailTokenProvider, will use the security stamp when they generate and validate a second factor code.
Thus, you can invalidate all issued tokens by changing the security stamp by calling UserManager.UpdateSecurityStampAsync(userId) after a successful two factor authentication.
There is a side effect that may not be desirable, being that other sessions will get logged out when the security stamp changes.
In the ApplicationSignInManager class, you can override TwoFactorSignInAsync and make the call there:
(Note: This is taken from AspNetIdentity, if you are using a different package, make sure to take TwoFactorSignInAsync from that instead and modify it accordingly.)
public override async Task<SignInStatus> TwoFactorSignInAsync(string provider, string code, bool isPersistent, bool rememberBrowser)
{
var userId = await GetVerifiedUserIdAsync().WithCurrentCulture();
if (userId == null)
{
return SignInStatus.Failure;
}
var user = await UserManager.FindByIdAsync(userId).WithCurrentCulture();
if (user == null)
{
return SignInStatus.Failure;
}
if (await UserManager.IsLockedOutAsync(user.Id).WithCurrentCulture())
{
return SignInStatus.LockedOut;
}
if (await UserManager.VerifyTwoFactorTokenAsync(user.Id, provider, code).WithCurrentCulture())
{
// When token is verified correctly, clear the access failed count used for lockout
await UserManager.ResetAccessFailedCountAsync(user.Id).WithCurrentCulture();
// Update the security stamp in order to invalidate all issued two factor tokens.
await UserManager.UpdateSecurityStampAsync(user.Id);
await SignInAsync(user, isPersistent, rememberBrowser).WithCurrentCulture();
return SignInStatus.Success;
}
// If the token is incorrect, record the failure which also may cause the user to be locked out
await UserManager.AccessFailedAsync(user.Id).WithCurrentCulture();
return SignInStatus.Failure;
}
If you want only the latest issued code to be valid, you should make the call to UpdateSecurityStampAsync also before any new code is generated.

ASP.NET MVC5 OWIN rejects long URLs

I am creating an ASP.NET MVC5 action method that implements a password reset endpoint and accepts a click-through from an email message containing a token. My implementation uses OWIN middleware and closely resembles the ASP.NET Identity 2.1 samples application.
As per the samples application, the token is generated by UserManager and embedded into a URL that is sent to the user by email:
var token = await UserManager.GeneratePasswordResetTokenAsync(user.Id);
var encoded = HttpServerUtility.UrlTokenEncode(Encoding.UTF8.GetBytes(token));
var uri = new Uri(Url.Link("ResetPasswordRoute", new { id = user.Id, token = encoded }));
The link in the email message targets an MVC endpoint that accepts the token parameter as one of its route segments:
[Route("reset-password/{id}/{token}"]
public async Task<ActionResult> PasswordResetAsync(int id, string token)
{
token = Encoding.UTF8.GetString(HttpServerUtility.UrlTokenDecode(token));
// Implementation here
}
However, requests to this endpoint (using a URL generated in the above manner) fail with Bad Request - Invalid URL.
It appears that this failure occurs because the URL is too long. Specifically, if I truncate the token segment, it connects correctly to the MVC endpoint (although, of course, the token parameter is no longer valid). Specifically, the following truncated URL works ...
http://localhost:53717/account/reset-password/5/QVFBQUFOQ01uZDhCRmRFUmpIb0F3RS9DbCtzQkFBQUFzcko5MEJnYWlrR1RydnVoY2ZwNEpnQUFBQUFDQUFBQUFBQVFaZ0FBQUFFQUFDQUFBQUNVeGZZMzd4OTQ3cE03WWxCakIwRTl4NkVSem1Za2ZUc1JxR2pwYnJSbmJ3QUFBQUFPZ0FBQUFBSUFBQ0FBQUFEcEpnVXFXS0dyM2ZPL2dQcWR1K2x6SkgxN25UVjdMYlE2UCtVRG4rcXBjU0FBQUFE
... but it will fail if one additional character is added ...
http://localhost:53717/account/reset-password/5/QVFBQUFOQ01uZDhCRmRFUmpIb0F3RS9DbCtzQkFBQUFzcko5MEJnYWlrR1RydnVoY2ZwNEpnQUFBQUFDQUFBQUFBQVFaZ0FBQUFFQUFDQUFBQUNVeGZZMzd4OTQ3cE03WWxCakIwRTl4NkVSem1Za2ZUc1JxR2pwYnJSbmJ3QUFBQUFPZ0FBQUFBSUFBQ0FBQUFEcEpnVXFXS0dyM2ZPL2dQcWR1K2x6SkgxN25UVjdMYlE2UCtVRG4rcXBjU0FBQUFEf
I believe that the default IIS configuration setting for maxUrlLength should be compatible with what I am trying to do, but I have also tried explicitly setting it to a larger value, which did not solve the problem.
However, using Fiddler to examine the server response, I can see that the working URL generates a server response with the following header ...
Server: Microsoft-IIS/8.0
... whereas the longer URL is rejected with a response containing the following header ...
Server: Microsoft-HTTPAPI/2.0
This seems to imply that the URL is not being being rejected by IIS, but by a middleware component.
So, I am wondering what that component might be and how I might work around its effect.
Any suggestions please?
Many thanks,
Tim
Note: Although my implementation above Base64 encodes the token before using it in the URL, I have also experimented with the simpler approach used in the sample code, which relies on the URL encoding provided by UrlHelper.RouteUrl. Both techniques suffer from the same issue.
You should not be passing such long values in the application path of the URL as they are limited in length to something like 255 characters.
A slightly better alternative is to use a query string parameter instead:
http://localhost:53717/account/reset-password/5?token=QVFBQUFOQ01uZDhCRmRFUmpIb0F3RS9DbCtzQkFBQUFzcko5MEJnYWlrR1RydnVoY2ZwNEpnQUFBQUFDQUFBQUFBQVFaZ0FBQUFFQUFDQUFBQUNVeGZZMzd4OTQ3cE03WWxCakIwRTl4NkVSem1Za2ZUc1JxR2pwYnJSbmJ3QUFBQUFPZ0FBQUFBSUFBQ0FBQUFEcEpnVXFXS0dyM2ZPL2dQcWR1K2x6SkgxN25UVjdMYlE2UCtVRG4rcXBjU0FBQUFEf
That should be safe for at least 2000 characters (full URL) depending on the browser and IIS settings.
A more secure and scalable approach is to pass a token inside an HTTP header.

login automatically with Grails & Acegi

I'm using the Acegi plugin in my Grails app. After a user registers, he is redirected to an action that is protected. Therefore, he is shown the login form.
However, I would prefer if the user was automatically logged in as soon as he completes registration. It seems like I could achieve this by redirecting to the action that the login form uses
redirect(uri:"/j_acegi_security_check?j_username=${username}&j_password=${passed}")
But this would send a HTTP request to the client (and back to the server) which shows the user's password. Is there a way I can login automatically in a secure fashion?
Thanks,
Don
If you generate the controller classes for the spring security plugin (grails generate-registration) you'll see the following lines in RegisterController which does just what you want:
class RegisterController {
def daoAuthenticationProvider
...
def save = {
...
def auth = new AuthToken(person.username, params.passwd)
def authtoken = daoAuthenticationProvider.authenticate(auth)
SecurityContextHolder.context.authentication = authtoken
redirect uri: '/'
}
Be sure that params.passwd is the plain-text password (i.e. not hashed) and it works like a charm.
I haven't tried this with non-test code, but this is the method that I created to log a user in within my integration tests (after building/saving the appropriate users/roles in my test setup):
import org.codehaus.groovy.grails.plugins.springsecurity.GrailsDaoAuthenticationProvider
import org.springframework.security.providers.UsernamePasswordAuthenticationToken
import org.springframework.security.context.SecurityContextHolder
...
def logInAsUser(username, password) {
daoAuthenticationProvider.getUserCache().removeUserFromCache(username)
UsernamePasswordAuthenticationToken token = new UsernamePasswordAuthenticationToken(username, password)
SecurityContextHolder.context.authentication = daoAuthenticationProvider.authenticate(token)
}
I construct and inject the authentication token in the security context. There might be a little more that you need to do to get your user logged in and past security, but this would be the start of whatever that is.
I'll actually need to do exactly what you're asking in a week or two for my current app, post back if you figure it out fully before I do :).
This is Burt Beckwith's answer (not mine)
(It was left as a comment by Burt, but I think it deserves to be more prominent)
If you don't have the password, you can load the user via
def user = User.findByUsername(username)
and setting the authority array in the 3-parameter constructor. Create the auths via
GrantedAuthority[] auths = user.authorities.collect { new GrantedAuthorityImpl(it.authority) }
Then you can omit the call to authenticate() and use:
SecurityContextHolder.context.authentication = new UsernamePasswordAuthenticationToken(username, 'unknown', auths)

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