Oauth authentication with a known user? - authentication

Most Oauth implementations require the user to login with the originating site in the process.
An example is: http://code.google.com/apis/accounts/images/OAuthDiagram.png
What if I want to use my own account to access a generic feature, such as a search for people outside of my network, and don't want them to login? Is there any way to login with my own generic account?
I am creating a web service that interacts with many social networks by searching them, so by forcing the user to login several times to each network if I want to use their API is just bad user experience.

You could try to authenticate your account manually and then store the access token. Any subsequent request would be made with the stored access token.
There are several problems with this approach:
if the token expires, you have to reauthenticate
you might run into request quotas if you do all requests from one account (e.g. Twitter)
If possible, I would use something like HTTP basic auth to authenticate to the services.

When you are strictly speaking of OAuth, it is not meant for this scenario. Try looking into SSO (Single Sign-On).
OAuth can also be implemented in conjunction with SSO solutions.

Related

Securely using JSON web tokens to programmatically authenticate a user from one system into another

My team and I have been working on a web application for our clients that uses JSON web tokens for authentication and authorization. Using Azure AD as our identity provider, we verify a user's identity and generate a signed JWT with the user's permissions in it. The JWT then gets included in the authorization header of all subsequent requests to the APIs. Pretty standard stuff as far as JWTs go.
We're now being asked to provide the capability to link directly into our system from another third-party web application without forcing the user to reauthenticate. I'm trying to figure out if there's a way to do so without creating a massive security loophole.
The way I picture this working would be to implement an endpoint for programmatic authentication in our system that accepts a cryptographically signed payload with an API key and the user's ID or email address. The third-party system would have a private key with which to sign the payload, and we'd have a public one to verify the signature. If the request is legitimate, we'd issue a token for the specified user, and they could use that to link to whatever they like.
I'm already getting yelled at by at least one person that this is a complete joke from a security standpoint because, among other things, it completely bypasses AAD authentication. I believe the third-party system in question does use AAD for authentication, but that's not really relevant either way because we're trusting them implicitly whether they've authenticated their users or not. Either way I take his point.
I'm not a security expert and I don't claim to know whether there even is a proper way to do this kind of thing, but from my vantage it doesn't really seem all that much less secure than any other mechanism of authentication and authorization using JWTs. Is that true? Are we nuts for even trying? Is there a way to do it that's more secure? What should I know about this that I demonstrably don't already?
Thanks in advance for the help. At the very least I hope this spurs some helpful conversation.
Single Sign-On (SSO) enables users to enter their credentials once to sign in and establish a session which can be reused across multiple applications without requiring to authenticate again. This provides a seamless experience to the user and reduces the repeated prompts for credentials.
Azure AD provides SSO capabilities to applications by setting a session cookie when the user authenticates the first time. The MSAL.js library allows applications to leverage this in a few ways.
MSAL relies on the session cookie to provide SSO for the user between different applications.
Read more in this documentation.

Does github (twitter, stripe & co) uses oauth for its own login?

Does github (twitter, stripe & co) uses OAuth for its own signin/signup forms?
All those authentications are cookie based, so is this regular web client basic auth or does it use some form of OAuth or xAuth ?
On login, a call to https://github.com/session (or https://twitter.com/sessions or https://dashboard.stripe.com/ajax/sessions) is made (with credentials given as formdata) that result in a 302 (or 200 for stripe) with Set-Cookie and a location to https://github.com (or https://twitter.com).
It does not seems that they use a client_id to get a code and exchange it with a token. All the OAuth dance seems striped. And the Bearer header too. So, what's going on here?
Thanks.
OAuth is a three-legged system, two-legs is sort of useless. The whole point of using OAuth is to give other services the ability to perform actions as you without needing to specifically authenticate or pass the data yourself. In the end you must still authenticate against some Auth service.
Since you are using these services as the Authentication mechanism for other sites, it wouldn't make sense to attempt to use it in your own. As part of setting OAuth, the second site redirects to the first and asked to authenticate there, which means you literally need to enter your credentials. Which means that if you are okay entering your credentials into say github, having a different authentication mechanism is useless.
OAuth allows non-github to create user accounts by trusting github with the authentication, or it allows non-github sites to make changes to github as the user once the user agrees to the interaction by logging into github to accept that policy (logging in using their credentials).
Sign in forms on github (and others websites as well) are simply cookie based.
Usually every direct login via the website through a browser is made with cookie based system , simply because isn't necessary to do otherwise.
A bit of theory
Every time you use a login form in a website you are calling an API, not necessarily intended for public use (so a private API)
When you put your credentials in the login form and push that login button , your credentials are being managed by some code in the server that permits you to authenticate against that website.
There is no need for the entire OAuth overhead here because the website has full control on the authentication mechanism and isn't necessary to externalize.
Why OAuth is different in this contest?
OAuth is a system designed to distribute the authentication system across different services / applications even from different vendors.
In OAuth there are multiple actors involved:
the client
the authorization server
the resource provider
In your case all these 3 actors are the website itself and so there is no need for a decoupling system like OAuth.

Login to Single Page Application with Google authentication and Google Oauth 2.0

We are developing an SPA - full client base javascript application and need to authenticate our users to get access to the internals.
As I found from the search we can outsource our authentication mechanism and use Google accounts for that. I learned from this site
https://developers.google.com/accounts/docs/OAuth2Login -
How to deal with Google API and mechanism for authentication.
In the short word, we need:
send request to google url with params to ask user to allow SPA use their personal data
in case of success we get a token from Google
we may use this token to get access to API we were asked and work with it.
This is described well and I understand it and have some JS code to make it happen.
What I do not understand.
I have an application with it's private data. I want use user's e-mail as the login, or user id (doesn't matter how to call it) to access app's internals, such as user's created tasks, user's profile, etc. So, to display user's created tasks in my SPA I need query database with the user's e-mail.
I imagine the next scenario:
user click Login with Google button
we obtain an token - this means user was authenticated successfully
we persist user and his e-mail to work with SPA
when user click Logout we clear all access data
Where should I persist this data?
In case of Forms Authentication I understand that we pass login/password to server and if they match the database we create Forms Ticket and store it in cookie.
Is there any similar case with Google's auth? If I'll store user's email in cookie I think that's not very good from security reason. If I'll save a token - I'm not sure why I need it and how to use it in my SPA, I'm not using any Google API after authentication.
Do you have any example case how do we build our process in similar cases?
Thank you.
If all you need is the user's email address, then you would be better off using OpenID instead of OAuth. OAuth provides access to a user's account and services, scoped to a specific resource or set of resources. OpendID is designed just for logging into a third-party service. You can then extract the user's ID and email address from the OpenID login. Note: The ID will always be sent but the email address has to be explicitly requested during authentication.
Google also supports a hybrid OpenID+OAuth scheme that lets you piggyback OAuth requests on top of an OpenID login if there is some resource you need to authenticate to. Take a look at the authentication document to get an idea of how both protocols work and which is better for your scenario.
Once you have the email address returned, you probably shouldn't persist it in a cookie. The normally recommended way to handle it is to add it as a session parameter. That way only the session cookie is stored on the client, and the server can use it find the values it needs. This answer has a good explanation of the differences and when you want to use sessions versus cookies.

Which is the better way to implement authentication using login/password AND other social networks?

I'm gonna try to explain my problem :
I'd like to allow users to connect to my api via their own accounts (login/password) or via a social network (Facebook at first).
Then, I would allow any application to use my api, with the user authenticated.
My first thought when to auth the user via his/her login/password and return a token used as the session for the next requests.
But OAuth would seems to be the better implementations, except I don't know how to do this :
One of my applications will have to connect via login/password, like twitter web (I have to implement an login/password auth somewhere if I wan't my user to login :p)
Will I also have to register my applications to the oauth system (did twitter added their web app to their oauth ?)
How to merge the auth via others social networks. Concretely, the user will have to OAuth to my api that will auth to the social network.
I'm a bit lost on how to do this, if someone could help me, I would really appreciate !
Thanks
Update 1:
Flickr and Lastfm seems to not use OAuth but an alternative auth system that looks like this :
The user is redirected to Flickr/Lastfm
The user auth himself and accept to use the application
Flickr/Lastfm return to the Callback url with a temporary frob (for flickr) or token (for lastfm)
The app must call the provider with the temporary frob/token (among with the api_key and the api_sig, as always) and get in return the session token to use for the next calls.
Update 2:
In fact, StackApps is the concrete case of my problem : you can login through their login/password system OR openId, and you can use their API.
OAuth is only needed to make others use your API on other services, i.e. authorize services to use your API without users of the intermediary service explicitly having to log in into your service by giving user's login credentials to a third party.
What I think you need is OpenID, the cross-application authentication mechanism. You just need to implement an OpenID client, accepting third-party OpenIDs to authenticate users, to subsequently identify them, when they use your service's API. This would have to be supplemented with a normal 'local' user authentication mechanism (i.e. login/password entry page)
You will need OAuth to provide an ability to use your API on other sites, though.

Using oAuth (Twitter, LinkedIn) for login to a web app

Should I use oAuth, for example LinkedIn or Twitter, as my signin mechanism for my app? It seems that most apps just use oAuth to connect other services to it, but they make you set up your own user/password after you use oAuth (including StackOverflow), and I'm not really sure why this is. Would love some insight here. Thank you.
Why not use OpenId, to allow people to sign into your application, without having to type any specific login/password ?
Quoting the corresponding wikipedia entry :
OpenID is an open, decentralized
standard for authenticating users
which can be used for access control,
allowing users to log on to different
services with the same digital
identity where these services trust
the authentication body. OpenID
replaces the common log on process
that uses a login-name and a password,
...
BTW, that's exactly how one logs-in on stackoverflow ;-)
OAuth purpose is not authenticating your users with your site, is letting your users allow you (the oauth consumer) access to their protected resources in other sites (oauth providers) like LinkedIn, Twitter, Google APIs etc.
For authentication, you should use OpenId as others have pointed
Twitter provides a Sign in with Twitter flow that is OAuth but provides a faster redirect if it is an existing user of your service and they are already authenticated with Twitter.
http://apiwiki.twitter.com/Sign-in-with-Twitter
If you are building a Twitter centric application this makes a lot of since to use and you won't have to implement an entire alternate authentication method like OpenID.
Be careful if you let users authenticate with both Twitter and LinkedIn as users will inadvertently create two accounts and need them to be merged.
Facebook and Twitter both have the "Login with Facebook/Twitter" APIs to actually allow users to login without having to create an account for your website. Both of them will return you a valid session that may (or may not) expire. So you actually wouldn't have to ask users to decide on a username/password, as you can fetch both from the APIs (you can not get the users email address when using Twitter though)
So why add those functions to your website?
Users are in general more likely to hit the "Login with ..." button than going through the whole mail address authorization process and entering their name, etc...
Linkedin only has OAuth for usage to its API. It will also depend on what type of language you are writing your webapp in, they should have premade wrapper libraries you could tap on to.