Laravel: API with OAuth 2.0 - laravel

I am currently developing an API that I plan to secure using oauth2.
I have chosen: https://github.com/lucadegasperi/oauth2-server-laravel/
I have managed to secure the endpoint (using before=>oauth in my api routes) by following the installation guide but I am at a loss as to how am I gonna be able to authenticate and access the endpoint.
I do understand that you will first need to request an access_token by sending a client_id and client_secret but what I don't get is where do I set those on the oauth server?
I see the oauth controller has endpoints for these like:
http://somedomain.com/oauth/authorize
http://somedomain.com/oauth/access_token
But I am clueless with what to do with them. I only managed to arrive at the conclusion that it needs a client_id, client_secret, and stuff about scopes.
Where can I set these values for the api client to use?
Thank you for your help in advance.

I don't know Laravel, but in general, the authorization endpoint (in your case, http://somedomain.com/oauth/authorize) behaves as described in RFC 6749.
The specification defines four flows. If you use Authorization Code Flow among the flows, you should access the authorization endpoint with the following request parameters.
response_type=code (required)
client_id={your-client-id} (required)
scope={space-delimited-scope-names} (optional)
redirect_uri={your-redirect-uri} (conditionally optional)
state={any-arbitrary-string} (optional)
For example,
http://somedomain.com/oauth/authorize?response_type=code&client_id=your-client-id&scope=profile+email
The authorization endpoint generates an authorization code and returns it to your browser.
The next step is to access the token endpoint (in your case, http://somedomain.com/oauth/access_token) with the authorization code which has been issued from the authorization endpoint. Like this,
POST
http://somedomain.com/oauth/access_token?grant_type=authorization_code&code=issued-authorization-code&client_id=your-client-id&client_secret=your-client-secret
Anyway, I recommend you read RFC 6749.

Related

Debugging The interface between Resource Server and Authorization Server (oauth 2.0. validation access token)

There are two spring-boot apps.
client
resource-sever
there is dev okta account that is used as auth server
(those 2 apps are standard Spring Boot client -> resource-server, almost out of the box with okta setup for them, should not be problem there)
client - securely sends messages to--> secure-sever (passing the access token in the header as prove that it's authorized to call it and get data back)
(it works as expected)
But I am trying to figure out what's going on between all them, traffic wise
I'm trying to spot that moment when resource-server checks the token it got from the client that got it from the auth server.
Here is a sequence diagram of standard oauth 2.0 flow and that part that I want to debug (arrow)
auth server
And there is a communications between client, resource-sever:
There seems I can not confirm that Resource Server (from the right) does any token validation with the auth-server (okta)..?
Question: is why? From my understanding it is supposed to validate it (somehow).
I was expecting to see a call from resource-server to auth-server (otka) with the token-validation-request (ETF RFC 7662 in October 2015) like this:
How to validate an OAuth 2.0 access token for a resource server?
I was expecting, lets say, tat for every client call, resource server would check if that token the client passes is valid. Yet I do not see any calls from resource service to okta that would use the token in its requests to okta.
This comes down to the difference between JWTs and opaque tokens.
It looks like your application is using JWTs, based on the calls I'm seeing to /keys.
When using JWT authentication the resource server will query the jwks_url (in this case /keys) on startup to retrieve a set of public keys that it can use to validate the JWT-encoded bearer tokens.
Then, when the resource server receives a bearer token in a request from the client it will validate its signature against a public key obtained from the jwks_url endpoint.
This means the resource server doesn't have to query the authorization server on every request.
You can read more about this process in the OAuth 2.0 Resource Server JWT section of the Spring Security reference documentation.
The question that you linked to refers to opaque tokens.
In this setup, the resource server must call the authorization server introspection endpoint to validate the token every time.
You can read more about this process in the OAuth 2.0 Resource Server Opaque Token section of the Spring Security reference documentation.

Integrate SAML authentication for APIs developed in microservices

I need to develop set of microservices (rest APIs) which is to be used by web and mobile client, the microservices are sitting behind API gateway, I've to integrate with SSO (using SAML) for user's authentication, I understand that SAML token to oAuth2 token conversion has to be done so that I can verify auth token at API gateway and handle authorization there itself, but the piece which is not clear to me is that who will take care of conversion of SAML token to oAuth2 token, is it IDP who provide this functionality out of box or do I need to built up something of my own?
One possible solution which I'm thinking of is
User (from web/mobile) sign in via SSO
Gets SAML response from IDP
Send that SAML response to server to generate Auth Token
Server gets request to generate auth token, looks for SAML response and validate it against IDP
If SAML response is valid then generate auth token and send it back to client
On subsequent API request from client the token is passed as header which API gateway validates
The thing is I'm bit reluctant to implement SAML and oAuth thingy myself and looking for some ready made solution but couldn't find any, can someone please suggest of any library solving this problem, thanks in advance.
It feels like your approach is correct - it is the role of the Authorization Server (AS) to deal with SAML login integration for you. Only configuration changes should be needed, though of course you need to use an AS that supports SAML integration.
Your UIs and APIs will not need to know anything about SAML and will just use OAuth tokens. There should be zero code changes needed.
Most companies use an off the shelf AS - eg from a low cost cloud provider. My Federated Logins Blog Post summarises the process of integrating an IDP. The walkthrough uses AWS Cognito as the AS - and the IDP could be a SAML one.
I maintain a microservice that sounds like it could help you - https://github.com/enterprise-oss/osso
Osso handles SAML configuration against a handful of IDP providers, normalizes payloads, and makes user resources available to you in an oauth 2.0 authorization code grant flow.
Osso mainly acts as an authentication server though - we don't currently have a way for your API gateway to verify an access token is (still) valid, but that would be pretty trivial for us to add, we'd be happy to consider it.

Additional parameter in oauth2 token request

I'm developing backend for oauth2 client. I'm using authorization_grant flow with PKCE extension. I'm trying to implement it in such way that code verifier and code challenge is generated on clients side. So i have to add additional parameters to my token request (the second request, when input is authorization code and my application exchange it for access token).
My app will have to take this code_verifier from request param and pass it to authorization server with authorization code, client id, and client secret.
So now I'm struggling with customizing spring-security-oauth2-client to add additional parameter. There is way to add such parameters to authorization request by implementing OAuth2AuthorizationRequestResolver, but is there analogical way for adding parameters to token request?
Or maybe should i implement this endpoint manually?
I feel your pain, since Spring OAuth Security is often poorly documented for common use cases. One option you might consider is to provide a custom Spring filter that uses the open source nimbusds libraries, which have very good documentation and are easy to use.

Which information gets sent in each API request using OIDC

I'm writing an API back-end that I want to use OpenID Connect (OIDC) to secure. I've been reading the documentation but I'm still a bit confused what process applies to each and every API request. The Open ID Connect code flow appears to be:
Which I'm fine with, as a one-time process. My back-end API sees an authorization code in the HTTP headers, and sends a request to the authorization server to get the id token. Assuming this validates OK, the data requested is returned in the API response.
But assuming the same user will then be making lots of requests to this API, what happens in subsequent requests? Is there some sort of session created in this mechanism? Do I continue to receive the same authorization code? Do I have to keep sending these back channel requests to the authorization server?
Or should I even output the JWT id token as a cookie? In this way I get the self contained id token coming back in future requests, with no need of a server side session, or further round trips.
I've been reading the documentation but I'm still a bit confused what
process applies to each and every API request
It is not the API that should follow OpenID connect protocol. It's the client that should do it.
My back-end API sees an authorization code in the HTTP headers, and
sends a request to the authorization server to get the id token.
Assuming this validates OK, the data requested is returned in the API
response.
Authorization code must be used by client application and not by the API endpoint. Also, authorization code must never be exposed to other entities.
You should use id token sent with OpenID Connect to authenticate the end user from your client application. To access API, you should use access tokens.
What to do in API endpoint ?
I think this is where you struggle. Your client application should send a valid access token to get access to API endpoint. From API endpoint, you can use OAuth 2.0 introspection endpoint to validate the tokens.
RFC7662 - OAuth 2.0 Token Introspection
This specification defines a protocol that allows authorized
protected resources to query the authorization server to determine
the set of metadata for a given token that was presented to them by
an OAuth 2.0 client.
Note that, OpenID Connect is built on top of OAuth 2.0. This means you can use anything defined in OAuth 2.0, including introspection endpoint. Use this endpoint to verify the access token validity.
What if you want end user details ?
OpenID Connect defines a user info endpoint
User info endpoint
The UserInfo Endpoint is an OAuth 2.0 Protected Resource that returns Claims about the authenticated End-User. To obtain the requested Claims about the End-User, the Client makes a request to the UserInfo Endpoint using an Access Token obtained through OpenID Connect Authentication. These Claims are normally represented by a JSON object that contains a collection of name and value pairs for the Claims.
Here also, you use access tokens to get user information from this endpoint. The response will let you know the end user to which this token was issued.
Depending on your specific API requirement, you can do a token introspection or obtain user information from user info endpoint. Once that is done you may go ahead and authenticate a session. You might use both endpoints if you need all available information.
Alternatively(instead of sessions) your API can maintain an access token cache. This will remove the need to validate tokens in each an every API call. But be aware that tokens have expiration time. You must consider about token expiration if you are choosing this solution.
p.s - Client vs Resource server
In OpenID Connect and OAuth 2.0 terms, a client could be a simple web page, desktop application or could be even server hosted application.
client
An application making protected resource requests on behalf of the
resource owner and with its authorization. The term "client" does
not imply any particular implementation characteristics (e.g.,
whether the application executes on a server, a desktop, or other
devices).
Obtaining tokens and using them is the duty of the client application.
On the other hand, resource server contains protected resources,
resource server
The server hosting the protected resources, capable of accepting
and responding to protected resource requests using access tokens.
Resource server exchange it's resources to access tokens. If we match the same scenario to basic authentication, access tokens replaces username/password sent with authentication headers.
Typically you'd secure a (pure) API with OAuth 2.0, not OpenID Connect. The Client accessing your API should obtain an OAuth 2.0 access token and in order to do that it may choose to use OpenID Connect to obtain that token. That is all independent of the API, which will only see the access token. The API (or Resource Server in OAuth 2.0 terminology) is not depicted in your diagram.

Transformation of token received from OpenID server

I currently have a distributed system containing an OpenID Connect server (IdentityServer3) acting as SSO server. The clients using the SSO server are AngularJS SPA:s with WebAPI v2 backends.
I got the basic login flow working, but I need some help with configuring the WebAPI/OWIN pipeline to allow transformation of the received token claims, ie. removing unnessecary claims and adding local claims. I'm assuming I need to create a local JWT instead of using the JWT received from the SSO server.
The question is, what is the best way of doing this? Are there OWIN middlewares that can help with this, or do I need to "manually" generate a new locally signed JWT from the claims received from the SSO server?
Current implementation details:
The AngularJS SPA authenticates against the SSO server using
authorization code flow and receives the authorization code.
The SPA posts the authorization code to the WebAPI.
WebAPI receives the authorization code and requests an AccessToken/JWT from the SSO server using the OAuth2Client class (part of Thinktecture.IdentityModel.Clients). This AccessToken is returned to the SPA to use in any further requests done to the WebAPI.
So my question mostly relates to step 3. How do I best change my current flow to generate a token also containing the local claims?
Also, what kind of authentication middleware should be used with your proposed solution (JwtBearerAuthentication, OpenIdConnectAuthentication or OAuthBearerAuthentication)?
Apoligizes for my probably confused terminology usage, I'm a beginner regarding OAuth and especially the OWIN pipeline. :)
Your WebApi should use BearerTokenAuthentication.
To get access token (access_token) and claims (id_token) in single call you need to set response type as ResponseType="token id_token"
You can checkout various ready to run sample at IdentityServer3 Samples. Specifically checkout implicit flow sample.

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