Background
I've made a web app. I log in to the web app using Sign in with Twitter. When the OAuth dance is done, I store these things about the user in the database:
The user's Twitter user ID
The user's OAuth token and OAuth token secret
A newly randomly generated token that I store in the user's browser as a cookie
Anytime the user visits the app and has the right cookie set, that user is signed into my web app as the correct user.
Problem
I'm now trying to build a mobile app that communicates with my web app through a RESTish API. I'd like to have a similar authentication scheme as the web app where requests from the mobile app include the same randomly generated token.
Twitter's SDK will handle Sign in with Twitter, at the end of which I'll have an OAuth token, an OAuth token secret, and the user's Twitter user ID. What's the best way to use these Twitter credentials to prove to my own server that I'm signed in as that Twitter user? My plan is that once I've proven this, I can have the server send me the generated token.
Assuming that you also have access to the consumer_key and consumer_secret on the server side, you can just send over the access token and have the server call the verify_credentials Twitter API with it: https://api.twitter.com/1.1/account/verify_credentials.json.
Related
Suppose that I have a mobile app with a frontend and a backend server.
My understanding is that -- when a user logs in the app with "Login with google", the frontend sends a request to the google auth server, and gets back an ID token. The documentation says that the frontend can then send the token to the backend server to establish a session. I imagine that means the token can be used in session-based authentication?
If I were to use token-based authentication (as opposed to session-based), do I just attach the ID token in every server request, and have the backend verifies it each time when processing a request? this page suggests the ID token should not be sent to the backend API. Which leaves me wonder what the correct procedure is for token-based authentication when using log in with Google.
So my question is: Does my server need to create an access token from the ID token from Google, and send it to the frontend, so the frontend can attach that access token in the API requests for authentication?
Thanks
Login with Google is an identity provider (IDP) operation. A full OAuth solution, including an authorization server (AS) looks like this:
Mobile app uses system browser to redirect to AS
AS returns a redirect response to the system browser, which routes to the IDP
User signs in at the IDP
IDP returns an authorization code to AS
AS swaps it for IDP tokens and carries out validations
AS issues a set of tokens to the app. This includes an access token (AT) with whatever scopes and claims are needed for business authorization to work.
Mobile app sends AT in API requests
API authorizes using scopes and claims from the access token
So ideally plug in an authorization server, to get this out-of-the-box behaviour. Another option is to implement your own token service, and issue your own tokens. That is less recommended though, since it requires more detailed understanding of the underlying security.
In auth0, a user authenticates themselves with auth0, then sends an access token to the app so that the app can make API calls. My question is: when the user authenticates themselves with auth0, what does auth0 send back to them? Is it an access token? If so, how does it differ from the access token that the user then sends to the app?
Thanks!
It gives them a token that you must verify with auth0 servers to make sure it's valid.
Auth0 sends back a few different types of tokens to the user.
The main ones are ID Token and Access token (as you have already mentioned).
Consider the following example assuming the setup of a web application & an API.
The user signs in to Auth0 through the web application and gets back the tokens mentioned above. The web application can then store the access token (for example in local storage) and attach this to requests to the API.
The API will see this token and can verify it has been issued by Auth0 and that the user has sent a valid access token. Then the API can know that the user is valid and can respond with privileged info.
To directly answer your question, the access token that the user gets back from Auth0 is the same one that it sends to the API. This will be sent around in jwt form which can be decoded when needed.
I'm implementing Facebook and Google SSO on my website using custom workflow (redirect urls, parsing on server side etc. - no javascript) and I got to the point I have access_token, token_type and expires_in and from Google also id_token and I am confused what to do next to authenticate the user.
I read a little about authorization vs authentication, and that Facebook and Google SSO is OAuth2 which provides authorization, but not authentication, from which I understand that this way my web application is authorized to do something on behalf of the user, but I cannot be sure the user is the one who I think he is? My main source is this: OAuth Authorization vs Authentication
So, my question is, what should I do to be able to can consider the user logged in.
Thank you
In your case google (and facebook) is authenticators. This services just tells your application that user who try to login to your system is the one who he wants to appear.
Assume you differentiate users by unique email.
Your application flow should be next:
The user try to login to application using google Application do all redirection google flow stuff and gives you tokens
Application need to store this tokens for future use
Application check if this user's email presented in database
If email is presented and google returns tokens (google authenticate your user successfully) you can login user in your app
If email isn't presented in database but google authenticate user successfully you can store this user (with email) to your database - sign it up - this is new user in your system
Same flow with Facebook. Surely you can extend this logic to be more your application specific.
SSO and OAuth are different. OAuth is authorization protocol.
You are dealing Google and Facebook oauth.
OAuth
In case of oauth, after successful authentication(google/facebook) you will get access token. You can use token for maintaining the user session.
With this token user is authorized, Now you should check whether the user is present in your database, if yes then authenticate the user and redirect to your application.
SSO
SSO is user authentication service. There are way to implementing SSO like kerberos SSO, ADFS SSO.
We should never use OAuth2 access token for authentication.
For details, please refer
https://oauth.net/articles/authentication/
The OpenIDConnect, built on top of OAuth2, can be used for authentication.
Google supports OpenIDConnect
https://developers.google.com/identity/protocols/OpenIDConnect
The basic idea is Google will issue the client app (your application) a ID Token after the user has login his Google account. You can then extract user information (e.g. email, unique user id) from this ID token and proceed your login flow.
I need to implement an authentication mechanism with JWT tokens for an mvc web application and a mobile application as well. Users will be able to register to our database and authenticate by using credentials (from signup) or use facebook single sign on. Both applications will use web API for data exchange with JWT token. I am thinking of using Identity Server 3 for that using Resource Owner Flow and i have some questions on that:
1) User will login from mobile application and will get a jwt token. Mobile application will verify it's validity and will refresh when needed. In order for mobile application to have user always logged in should i store refresh_token on device??? Is it secure?
2) I cannot understand how am i going to handle facebook authentication and get jwt token from identity server. Should i first get users email from facebook profile data and then what???
Thank you
1- You can store refresh token in database( identity server provide a token stor)
also you can use third party library to store tokens in device securely.
2-To use the 3rd party logins you need to do the redirect style to the IdSvr login page. Using resource owner password flow means you miss out on all the features in the token service like SSO, 2fa and federated authentication.
I don't quite understand the api flow for twitter on a per-user basis for API transactions.
Here's my understanding of the user transaction flow:
1./ User signs into our web application.
2./ User authenticates with twitter and then the API sends the user back to a callback destination with a provided oauth_token and oauth_token_secret.
3./ We store the oauth information into a database.
4./ Now we have there access tokens and can send tweets on their behalf without needing them to log into the application again.
HOWEVER, this is not working correctly. When I try to supply the oauth token information, i'm getting invalid or expired token. OK so instead i supply the oauth token provided to me with the user oauth tokens given by the owner of the app and it works.
I think I'm mishandling the authentication process.
I'm reading here at the authentication docs.
Can anyone help me understand how i get my app to handle status updates on a per user level?
Thanks.
Ok. However I read for twitter there is no expiration
This is the actual transaction flow your application will take in order to use Twitter:
Register your application to Twitter to obtain an OAuth consumer_key and consumer_secret. This is for Twitter to identify the application that your user will authorize to access it's account.
When the user wishes to Tweet or access their Twitter resources through your app, The OAuth handshake process will redirect to Twitter, with the application's consumer_key so that the user will authenticate on Twitter directly. Once user authentication is successful, Twitter will provide your application with an access_token.
That's essentially what happens, except that Twitter uses OAuth 1 protocol so the handshake is more lengthier.
Access Tokens do expire for security reasons. It's like when you login to a system, the session is active for a period. When they do expire, you will have to request for an access token again.
I don't know if that explains your question.