I'm developing an application with OAuth 2 feature. But my case is special. I only want to use my own account to login. Let me take the Facebook as an example to explain the flow of my application:
User start the application
Normally the OAuth will request the user login to his/her own FB account to authorize. But in my application, I want to login to my FB account. Because I know the my own user id and password. Is it a method to login to my account silently?
User is able to post message. In this case, they will post to my FB account.
Is this possible? Do you have any suggestion? Thanks
OAuth 2.0 allows for this type of flow, as defined in the so-called Resource Owner Password Credentials (ROPC) grant. However this flow is less preferred and for backwards compatibility only because it defeats OAuth's primary goal of not having to enter end-user credentials in the client.
FB does not support the ROPC grant so you'll have to go through the regular Authorization Code flow. Once you get a refresh_token through that initial flow, you can use that as a long-lived credential to get new access tokens in the same way that you would use the FB username/password.
Related
I'm currently unfamiliar with the OAuth2.0 Authorization Code Flow and I've read many articles about it and currently I still don't know how to properly implement it. So far, what I know about the flow:
User Logs in using OAuth
User is redirected to the authorization server for authorization code
Callback for permission/scope
Redirected to authorization server for access token in exchange for authorization code
Redirect back to the client with the access token
Client uses access token to access resource server.
Right now, what I'm still confused is that where should the login validation come (Login of username - password)? Is it a separate validation before going to OAuth flow and once the user is valid, it should go back to the flow?
I have some resources that explain OAuth 2.0 using Google Sign in as an example. Let me try to rephrase it according to your question.
Let's use the example of a user logging-in to Intercom using "Sign in with Google".
The user presses the button "Sign in with Google". This will redirect to the identity providers /authorize endpoint (could be different for each provider) which go to their login page.
The user is redirected to Google's accounts page. If not already logged-in, the user can enter their Google email/password here.
Google redirects back to Intercom with an authorization_code (for example, it redirects to https://intercom.com/authcallback?code=XYZ...)
Intercom's backend server sends this authorization_code with the client_id and client_secret (from their project in google), and receive an access_token (usually to the /token endpoint)
Intercom can then use the access_token to access the user's profile from Google.
So to answer your question, the user can enter their email/password inside the OAuth provider's page. Keep in mind that OAuth 2.0 doesn't specify how the provider is authenticating the user. This means, that the OAuth provider can authenticate their users in different ways, like email/password, email magic-link, SMS OTP, etc. Your website is just supposed to trust the OAuth provider that they are authenticating the user for you correctly.
Some extra resources that would help you understand OAuth 2.0 more:
How to store the OAuth 2.0 access and refresh token in your front end
Picking the right OAuth 2.0 flow
login validation come (Login of username - password)?
OAuth 2.0 NOT an Authentication protocol
The OAuth 2.0 specification defines a delegation protocol
Any use of username - password is outside of OAuth 2.0 and you should be looking at Open ID Connect which is an authentication protocol built on top of OAuth 2.0.
Best current Practice for Authorization Code flow is to use PKCE on OAuth or OpenID Connect.
The usual solution is to externalise both OAuth 2.0 and Open Id Connect from your code by using a mature security library. When you're new to this type of security there is a learning curve. My resources will give you an idea of how it all fits together:
Code Sample
Tutorial Blog Post
The libraries you integrate depend on the technology stack you are using. The resources above are for a Single Page App and NodeJS API.
Here is my Problem statement:
I want to do OAuth authentication with external Authorization Server(say External Identity Provider) But user should provide credentials on my custom login page. I know when we do Oauth user must be redirected to Identity provider to authenticate and complete OAuth dance. But in my case, I want user to provide credentials on my login screen. No where in the process, user should see the identity provider login page. Any thoughts?
If the user enters his credentials on your login page, how will your app verify these creds with the identity server?
The idea of oAuth is that you app (the client app) will not be exposed to the user's creds.
Note: If there is a tight relationship between the client app and the identity-provider (e.g. Facebook and the Facebook app for mobile) so you can perform this with Resource Owner Password Credentials grant type.
I have implemented an OAuth2 register workflow (in Java) according to rfc6749
I'm using GitLab as OAuth2 Provider.
After the user granted access to my application for his account, I get an OAuth Token (along with refresh token and other stuff), I am able to make API requests on behalf of the user, so this is working fine.
This way I can get the users e-mail adress which I use to create an internal user.
My questions are:
Is it practice to issue a token that is generated by my application for the user (along with the OAuthToken) or should I just use the token that has been issued by the OAauth Provider? (My App also has local auth with bearer tokens). This token will be used for further API - CLIENT communication (stored in Angular2 local storage as bearer)
How to do login only? When a OAuth User accesses my web service, how do I know that this user is a OAuth User and which OAuth Token belongs to him? How can the user login without providing e-mail or password? (The user has no password) I guess I have to redirect him to the OAuth Provider again, but I don't want my user to grant access everytime he logs in.
Answer 1:
Though you can use the token provided by OAuth provider, you SHOULD NOT use it considering the risk that may arise exposing it to the public.
Instead you should securely save the token provided by OAuth provider into the database and use another token for authentication of further api calls. (you could use JWT)
Answer 2:
There are two types of systems
Which always uses OAuth provider for identifying user. (Ex. Tinder)
Which provides both OAuth Login and Traditional login/signup. (Ex. Quora, Instagram)
If you want your application to follow 2nd approach, you should ask the user to create password for the first time when the user logs in using OAuth provider.
This will allow the user to log into your application by both methods, traditional as well as OAuth
To identify users of your application, you should either use HTTP session or issue your own tokens. Do not use tokens generated by the OAuth2 provider - they are meant to be used just by your backend (in role of an OAuth2 client).
To use an external authentication in your application, you probably want to use OpenID Connect, not a bare OAuth2. OpenID Connect extends OAuth2 and it's meant for authentication instead of the rights delegation. Then you use an implicit flow (instead of authentication code grant) with scope=openid, your frontend app (HTML+JavaScript) gets an ID token signed by the OAuth2 provider. After successful signature verification, your backend can trust that the client is the one described in the ID token (in its "sub" field). Then you can either keep using the ID token or generate your own token.
I am in the process of designing an app that is supposed to let you login using either a username/password combination or facebook login. We have a custom OAuth server that uses user credentials to authenticate users. Now, the question is how to add facebook into this.
As I see it now, when the user wants to login with facebook, the client does all the work and gets the access token in the end. But how do we let our server know that this access token is a good one (and corresponds to a user in the database)? To me it seems like our OAuth server should be able to handle this as well, and I'm just missing the how.
OAuth supports different scenarios (flows). Client-does-all-the-work is so called "implicit" flow.
In your case it would be better to use authorization-code flow and extend your OAuth server. You put a "Facebook" button on your login page and instruct Facebook to redirect to a new special page on your OAuth server. Delivered authorization code then can be exchanged to the access token inside of your OAuth server and the server may issue its own session and tokens based on this.
I'm using Rails to write an API for mobile application and OAuth seems like a standard way to handle user authorization.
If I understand Doorkeeper docs correctly it requires user to be signed in with the website before it grants access for the mobile app.
The issue in may case is that there really isn't any website (it may be in the future but for now it's just api). I would like the user creation/signing in etc be handled in the ios application.
This makes me wonder if OAuth is the correct solution here?
The OAuth "Resource Owner Password Credentials Grant," according to rfc6749 Section 4.3, will grant an authorization token and optionally a refresh token given user name and password. Thus the mobile app doesn't have to store user name and password to gain authorized access. It becomes like a long running session using token and refresh token. OAuthClientSetup an iOS example that runs against a doorkeeper api.
So there is the OAuth method for gaining authorization without having web site login authentication and access grant.
What is left is how to register new users from your mobile app. Agree that does not look to be covered by OAuth. OmniAuth will let you register a user authorized by a third party site. You allow the user to be the user they are on Twitter or FaceBook, StackOverflow or GitHub or wherever else. Maybe that would help.