Token Authentication in Devise - ruby-on-rails

I am a beginner in the world of Rails. Can someone please explain to me like I am a 2 year old. What in the world does token authentication do? Is it recommended for your app from a security standpoint or you are fine just without it???

Token authentication is usually used to create auto-signin links in your emails.
User clicks on link like http://example.com/some_page?auth_token=some-very-secret-token, which contains token and is recognized by token value.
So there is no need to remember password to unsubscribe from your site emails, for example.

Security tokens provide the "what you have" component in 2 factor / multi-factor solutions.
As talking to a two year old,
You want to get in the house. You would need a 'key' - a token that the system can identify you with.

Related

OAuth Google - Token refresh

Apologies for typos if any on my phone. We have been trying to put together a solid integration for several providers and aside from Twitter and their non existent email address (oh "good bye" unique key) we have Google with their extremely short token lifetime.
For now we resorted to performing a fake refresh by pushing user through flow on clientside in js.
How would one go about refreshing token without pushing user through the oauth flow without having Offline Access accessType? As refresh tokens are only valid for this accessType.
If i am missing a trick please let me know! All the social providers seem to follow different approaches as expiry does not seem to be exactly specified anywhere so in some cases it is a unixtime stamp some it is a negative integer in seconds relative to now (im guessing it has to be based on UTC or that wont work) and ive seen some that provide expiry as a unix timestamp. Damn was there no RFC for OAuth 2??
Any insights appreciated. Thank you.
Update
Apologies for the lack of clarity. Everything works, it's just Googles OAuth tokens are so shortlived. It's not a showstopper, it's just not ideal that we have to refresh Google's OAuth tokens with JS or use 'accessType' offline.
You don't say anything in your question about the specific OAuth flow that your app is using, so it's hard to provide a solid answer.
Two approaches tha spring to mind:-
If you're doing client JavaScript auth, then you can set immediate=true to the "refresh" is done without any user UI.
You can do the offline bit which wins you a refresh token. You could store that on a server and use it to generate access tokens as needed.

User Authentication into Devise from iOS

I am creating an application where user is going to sign in with username and password. At the back end and also for the website I am using ruby on rails where the authentication is handled by Devise. With the last edition of Devise they have depriciated the Authentication Token. I am lost in terms of how to authenticate from iOS ? Any suggestions ? How am I going to modify the gem files etc.
See this gist from Jose Valim Safe or Unsafe Tokens
Basically you will want to write your own auth token methods. You need to generate tokens and later compare them. You should read all of the comments, the discussion is pretty good.

Is devise's token_authenticatable secure?

I'm building a simple api with Rails API, and want to make sure I'm on the right track here. I'm using devise to handle logins, and decided to go with Devise's token_authenticatable option, which generates an API key that you need to send with each request.
I'm pairing the API with a backbone/marionette front end and am generally wondering how I should handle sessions. My first thought was to just store the api key in local storage or a cookie, and retrieve it on page load, but something about storing the api key that way bothered me from a security standpoint. Wouldn't be be easy to grab the api key either by looking in local storage/the cookie or sniffing any request that goes through, and use it to impersonate that user indefinitely? I currently am resetting the api key each login, but even that seems frequent - any time you log in on any device, that means you'd be logged out on every other one, which is kind of a pain. If I could drop this reset I feel like it would improve from a usability standpoint.
I may be totally wrong here (and hope I am), can anyone explain whether authenticating this way is reliably secure, and if not what a good alternative would be? Overall, I'm looking for a way I can securely keep users 'signed in' to API access without frequently forcing re-auth.
token_authenticatable is vulnerable to timing attacks, which are very well explained in this blog post. These attacks were the reason token_authenticatable was removed from Devise 3.1. See the plataformatec blog post for more info.
To have the most secure token authentication mechanism, the token:
Must be sent via HTTPS.
Must be random, of cryptographic strength.
Must be securely compared.
Must not be stored directly in the database. Only a hash of the token can be stored there. (Remember, token = password. We don't store passwords in plain text in the db, right?)
Should expire according to some logic.
If you forego some of these points in favour of usability you'll end up with a mechanism that is not as secure as it could be. It's as simple as that. You should be safe enough if you satisfy the first three requirements and restrict access to your database though.
Expanding and explaining my answer:
Use HTTPS. This is definitely the most important point because it deals with sniffers.
If you don't use HTTPS, then a lot can go wrong. For example:
To securely transmit the user's credentials (username/email/password), you would have to use digest authentication but that just doesn't cut it these days since salted hashes can be brute forced.
In Rails 3, cookies are only shrouded by Base64 encoding, so they can be fairly easily revealed. See Decoding Rails Session Cookies for more info.
Since Rails 4 though, the cookie store is encrypted so data is both digitally verified and unreadable to an attacker. Cookies should be secure as long as your secret_key_base is not leaked.
Generate your token with:
SecureRandom.hex only if you are on Ruby 2.5+.
The gem sysrandom if you are on an older Ruby.
For an explanation on why this is necessary, I suggest reading the sysrandom's README and the blog post How to Generate Secure Random Numbers in Various Programming Languages.
Find the user record using the user's ID, email or some other attribute. Then, compare that user's token with the request's token with Devise.secure_compare(user.auth_token, params[:auth_token].
If you are on Rails 4.2.1+ you can also use ActiveSupport::SecurityUtils.secure_compare.
Do not find the user record with a Rails finder like User.find_by(auth_token: params[:auth_token]). This is vulnerable to timing attacks!
If you are going to have several applications/sessions at the same time per user, then you have two options:
Store the unencrypted token in the database so it can be shared among devices. This is a bad practice, but I guess you can do it in the name of UX (and if you trust your employees with DB access).
Store as many encrypted tokens per user as you want to allow current sessions. So if you want to allow 2 sessions on 2 different devices, keep 2 distinct token hashes in the database. This option is a little less straightforward to implement but it's definitely safer. It also has the upside of allowing you to provide your users the option to end current active sessions in specific devices by revoking their tokens (just like GitHub and Facebook do).
There should be some kind of mechanism that causes the token to expire. When implementing this mechanism take into account the trade-off between UX and security.
Google expires a token if it has not been used for six months.
Facebook expires a token if it has not been used for two months:
Native mobile apps using Facebook's SDKs will get long-lived access
tokens, good for about 60 days. These tokens will be refreshed once
per day when the person using your app makes a request to Facebook's
servers. If no requests are made, the token will expire after about 60
days and the person will have to go through the login flow again to
get a new token.
Upgrade to Rails 4 to use its encrypted cookie store. If you can't, then encrypt the cookie store yourself, like suggested here. There would absolutely be no problem in storing an authentication token in an encrypted cookie store.
You should also have a contingency plan, for example, a rake task to reset a subset of tokens or every single token in the database.
To get you started, you could check out this gist (by one of the authors of Devise) on how to implement token authentication with Devise. Finally, the Railscast on securing an API should be helpful.
You can try to use rails4 with your API, it's providing more security and use devise 3.1.0rc
In Rails 4.0, several features have been extracted into gems.
ActiveRecord::SessionStore
Action Caching
Page Caching
Russian Doll-caching through key-based expiration with automatic dependency management of nested templates.
http://blog.envylabs.com/post/41711428227/rails-4-security-for-session-cookies
Devise 3.1.0.rc runs on both Rails 3.2 and Rails 4.0.
http://blog.plataformatec.com.br/2013/08/devise-3-1-now-with-more-secure-defaults/
Devise is deprecation of TokenAuthenticatable in 3.1.0rc but you can build your own TokenAuthenticatable method for security issue. It's more reliable and secure.
For token, session store you can go through http://ruby.railstutorial.org/chapters/sign-in-sign-out and http://blog.bigbinary.com/2013/03/19/cookies-on-rails.html for more understable.
At last you should go through these kind of encryption and decryption "Unable to decrypt stored encrypted data" to get the more security.

How should I secure my SPA and Web.API?

I have to implement a web site (MVC4/Single Page Application + knockout + Web.API) and I've been reading tons of articles and forums but I still can't figure out about some points in security/authentication and the way to go forward when securing the login page and the Web.API.
The site will run totally under SSL. Once the user logs on the first time, he/she will get an email with a link to confirm the register process. Password and a “salt” value will be stored encrypted in database, with no possibility to get password decrypted back. The API will be used just for this application.
I have some questions that I need to answer before to go any further:
Which method will be the best for my application in terms of security: Basic/ SimpleMembership? Any other possibilities?
The object Principal/IPrincipal is to be used just with Basic Authentication?
As far as I know, if I use SimpleMembership, because of the use of cookies, is this not breaking the RESTful paradigm? So if I build a REST Web.API, shouldn't I avoid to use SimpleMembership?
I was checking ThinkTecture.IdentityModel, with tokens. Is this a type of authentication like Basic, or Forms, or Auth, or it's something that can be added to the other authentication types?
Thank you.
Most likely this question will be closed as too localized. Even then, I will put in a few pointers. This is not an answer, but the comments section would be too small for this.
What method and how you authenticate is totally up to your subsystem. There is no one way that will work the best for everyone. A SPA is no different that any other application. You still will be giving access to certain resources based on authentication. That could be APIs, with a custom Authorization attribute, could be a header value, token based, who knows! Whatever you think is best.
I suggest you read more on this to understand how this works.
Use of cookies in no way states that it breaks REST. You will find ton of articles on this specific item itself. Cookies will be passed with your request, just the way you pass any specific information that the server needs in order for it to give you data. If sending cookies breaks REST, then sending parameters to your API should break REST too!
Now, a very common approach (and by no means the ONE AND ALL approach), is the use of a token based system for SPA. The reason though many, the easiest to explain would be that, your services (Web API or whatever) could be hosted separately and your client is working as CORS client. In which case, you authenticate in whatever form you choose, create a secure token and send it back to the client and every resource that needs an authenticated user, is checked against the token. The token will be sent as part of your header with every request. No token would result in a simple 401 (Unauthorized) or a invalid token could result in a 403 (Forbidden).
No one says an SPA needs to be all static HTML, with data binding, it could as well be your MVC site returning partials being loaded (something I have done in the past). As far as working with just HTML and JS (Durandal specifically), there are ways to secure even the client app. Ultimately, lock down the data from the server and route the client to the login screen the moment you receive a 401/403.
If your concern is more in the terms of XSS or request forging, there are ways to prevent that even with just HTML and JS (though not as easy as dropping anti-forgery token with MVC).
My two cents.
If you do "direct" authentication - meaning you can validate the passwords directly - you can use Basic Authentication.
I wrote about it here:
http://leastprivilege.com/2013/04/22/web-api-security-basic-authentication-with-thinktecture-identitymodel-authenticationhandler/
In addition you can consider using session tokens to get rid of the password on the client:
http://leastprivilege.com/2012/06/19/session-token-support-for-asp-net-web-api/

Google OpenID unique identifier problem

i recently asked question which was closed down linked here.
https://stackoverflow.com/questions/3827349/how-to-use-one-openid-across-multiple-domains-closed
I did not even had time to correct myself. somebody mis interpret it, changed title, somebody else think it is not relavent and closed it. :(
The problem is with Google OpenID system. They are security freak. Which is good. but When we use their OpenID system, they provide DIFFERENT UNIQUE FEDERATED IDENTITY URL FOR SAME USER BUT FOR DIFFERENT DOMAIN. i.e. if i login in to meta.stackoverflow.com with Google openID and then I login in to something.com with Google OpenID, they two will not have same unique identifier of myself. so, when two domain merge, they can not recognize same user across domain. either they have to use their email id or some additional information. I wanted to know if using some other information with openID is secure enough ? I read that, anything apart from unique identifier ( i.e. nickname, email, dob etc ) is not secure enough for openID and we should not use it apart from casual use.
got it.
http://stackauth.com/
they are using common domain and not different domain. which explains everything.
https://blog.stackoverflow.com/2010/09/global-network-auto-login/
A blog post about it.
:)

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