ASP.NET Authorize the same user as the one in the URL and JWT Token - asp.net

A user can edit only his own profile. I would like to achieve that with the .NET Identity framework. Let's say a request comes to path /api/users/{username}, and in the requests header there's a JWT Token too, which contains the user's username. If the username in the URL is the same as the one in the JWT Token, only then could the data be returned or modified.
I don't think this could be achieved just with Annotations, but what is the right way to do it?

Related

Need help setting up Postman Collection Authorization with API Token and Credentials

I am learning to connect to one of our 3rd party's API, and the first step in doing so is to first get an access token to use for additional requests.
To get that access token, I send a POST request that includes an API key in the header, along with the username and password in the body (as JSON). And that successfully returns a token.
But how do I set up that up in a collection? In postman I have options of API token, Basic Auth, Oath2, etc. But I do not see how you set up and include both the API key and user/password.
I've tried different scenario's of just the API Key and Oath2 with credentials, but unsure how you set it up to include both.

How do I structure authentication with a social IdP?

My system works as follows;
I have an ASP.Net RESTful API server, which contains a user database.
I also have a Xamarin.Forms application, with a registration and login page.
What I want is to have the ability to authenticate a login using a social IdP, and then, if that user has not been logged in before, register that user in my local database.
I have been reading up on how to implement OAuth 2.0 with OpenID Connect to authenticate my users with a social IdP, however, I cannot seem to wrap my head arround it. From what I've read, I shouldn't use an Access token for authentication, since that i what the ID token is for, however, I have also read that the only intended purpose for an ID token, is the client.
My problem then is, how can I make sure that calls made to my ASP.Net server, has been made by "real person", and how do I determine who makes the call?
Access token will be used determine whether the client application was authorized by a user to access a resource. The concept of ID token comes from OpenID Connect. Main purpose of the ID token is to authenticate the user to the client application (i.e. letting the client application know that the person who authorized the access is a valid person).
To do this, you have to validate the ID token. This can be done using third party libraries such as nimbusds or auth0. You can validate the signature of the token verify the integrity of the token and check the claims included in the token (by comparing them with expected values) to verify the user details. Also, you can add custom claims (any claim that is specific for your application/implementation) to the tokens through your identity provider so that you'll be able to validate those particular claims in order to verify the user.

Firebase - Custom oAuth2 service - Authorization code?

There is an app that wants to authenticate with my users using oAuth2.
So they open a window, with the authorize URL, and parameters (such as redirect uri)
Like: https://my-website.com/api/authLauncherauthorize?redirect=SOME_URI
Now I have my own firebase-login, and when the user logs in, I get their access token from firebase. Which is what I want to respond with.
However, in oAuth2 guides/explanations like https://aaronparecki.com/oauth-2-simplified/ I see I am supposed to return an authorization code, and I don't understand where can I get that from?
What I can do, is generate a bullshit code, pair it in the DB to the access token, and then in the "token" request, send the correct access token. Is that what I am supposed to do?
Just to be clear, this is my first time writing an oAuth2 service myself.
OAuth is a system that provides authenticated access to resources. This resource can be for example a user page or editing rights to that user page. So your goal is to provide access to permissions to the right people.
When someone logs in, they get a token. Your part is to generate that token however you want, may it be some form of userdata into base64 or completely random. Take this token and link it against permissions, like viewing a page, editing it or even simpler things like viewing the email of a user.
OAuth2 tokens and/or permissions should be revokable without deleting a user. You should not use OAuth2 to identify someone.
If I am understanding your question correctly:
User visits some website
User wants to register or login using your websites OAuth2
You redirect back to the original page and send your generated token
The page can access content on your site with this token
Assuming you are the Host Site, given a User who wants to connect a 3rd party application, then the flow would be like this:
User lands on site - Clicks Login with Github
User is redirected to Github site where they login and click "Authorize"
Github redirects user back to your site /authorize with an auth token.
Your site then passes that token back to the 3rd party API (github in this case) in exchange for an access token and refresh token.
You can then pass that Authorization token to an API endpoint to get details about it. If the token expires, you can use the refresh token to get a new Auth token. Both Tokens should be stored in your database for your user.
However writing that all out I realize you are asking how do you generate the Authorization token, so I'm guessing you're actually the 3rd party API in this example. So you would want to generate an Authorization token using a random generator. Since you are using firebase, you'll probably wanna try out their token generator: https://github.com/firebase/firebase-token-generator-node
There's also some more up-to-date info here I believe: https://firebase.google.com/docs/auth/admin/#create_a_custom_token
And like you said, you would store that in a database associated with the user, and then when the Host Site sends that user's auth token to your server, you exchange it for the Authorization token (and refresh token if requested).
It's also worth reading through how google does it, because you'd be doing something similar: https://developers.google.com/identity/protocols/OAuth2UserAgent#validatetoken
JWT is another option of generating tokens: https://jwt.io/

/oauth/token from Controller

I want to implement oauth2 in my website.
I have the server configured.
In current scenario there is a login page, where user puts her credentials which in turn is submitted to my login controller. Now I want to authenticate user using oauth2. Since the server and client are part of same application I am wondering how to go ahead.
I want to authenticate the user via oauth and return the dashboard along with the bearer token so that next call can me made from here.
Please suggest how to go ahead. If there is a better way to do i am more than happy to adapt it.
Thanks
Configure authorization server with spring-security-oauth. All the necessary endpoints will be mapped automatically (including /oauth/token)
Make a simple webpage with login form
Make POST request to /oauth/token with the username and password. In addition you have to send field called grant_type which will be filled with 'password' value.
As a response you will receive the access token. This means that you are authenticated.
P.S. Please pay attention that Oauth is the authorization standard, not the authentication one!

ASP.Net and Facebook: Logging-in via ASP.Net

I want to enable Facebook authentication and the FB-Graph in my website, which already has forms authentication. Using http://multitiered.wordpress.com/2010/08/05/getting-started-with-the-facebook-c-sharp-sdk/, I was able to figure out how to login server-side.
However, the problem with this approach is that a secure cookie will not be created, since the call returns the authentication code in the querystring via a callback. This means that the user will have to login every time.
I can see two ways around this:
Store the access token in a secure cookie manually
Instead of the above approach, use the FB JS API to login - this stores a secure cookie with the access token automatically
I would prefer not to use the second approach, as I would like the login code to be server-side.
Which would be the better approach? Am I missing something?
I use the JavaScript method to first authenticate the user, the JS SDK then writes an encrypted cookie (called "fbs_[YourAppID]") when a connected user hits your page; using one of the many Facebook c# SDKs, this cookie can be decoded using your application secret giving you the user ID, oAuth token, expiry date etc.
Then I hook into the AuthenticateRequest event of my .NET application, check the presence of the cookie, decode if it found, and then find a user who has been assigned this facebook ID (your user table must have a extra field for storing the ID of their facebook account).
If a match is found, I write a normal forms authentication cookie for this user, then .NET will recognise them for all future requests. If no user is found, then this is a brand new user who has just connected. Use the SDK again to query the graph API using their oAuth token, get things like their name/email etc and create a new account, then issue a authentication token as normal.
By writing a normal authetication cookie, the user will stay logged into to your site for all requests, just as if they were a normal user.
One side point, when using email address, check for duplicates, and check for the facebook cookie in all requests. For example, an existing registered logged in user may have just connected.

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