I am building an application using microservice architecture. I am using Eureka for service discovery with Spring Cloud Gateway for request routing. For authentication mechanism I am issuing JWT tokens (in auth service). What is the best practice when it comes to propagating Authentication so I can get logged user information in each service which is after the gateway?
So far I've came up/found couple of possible solutions:
In gateway add headers for relevant user information, and in each service create filter which would take said headers and create Authentication object and store it into SecurityContextHolder. The downside of this approach is I can't just plug and play services outside my application.
Pass the token coming from the client through the gateway to the each service, where I would have JWTFilter which would validate token and extract the user information. Downside I see with this approach is I have to have jwt secret shared between each service or stored on each service, and I would have to implement JWT logic, producing duplicate code.
Final solution is having something like oAuth token introspection endpoint in auth service which would be called from each service (filter) once the request reaches it.
I implemented the filter logic for validating the user token in the gateway service, but I would like to use role based authorization on each endpoint (service) differently (ie. user service has endpoint for creating users (ADMIN), and for fetching user information (ANY ROLE)).
I opted for something like your option 2 and use spring-boot to configure JWT decoder from an OIDC authorization-server (Keycloak).
Configuring OpenID resource-servers is super easy (more options in parent folder), and authorization-server JWT public signing key is retrieved automatically by spring JWT decoder.
All that is required is ensuring that Authorization header with JWT bearer is correctly propagated between services.
Related
I have 2 secured resource microservices and 1 authentication service and another API Gateway.
Authentication service can generate JWT Token given username and password. It also can validate a JWT token.
So, I want to implement security at the API Gateway only such that on receiving a request, it will first fetch a bearer token from the authentication service and forward the request to the secured resource service. I would like to get some idea how to implement that in API Gateway. Should I make it just in an aggregate fashion, like it would be a sync call which will first make a request to auth service and next forward the request to resource service?
Now, if I want to add the support of OAuth as well, which I know the spring cloud API Gateway already has the support for this via global filters.
But, I am wondering about the legacy bearer token which is generated by the custom authentication service.. How do I ensure this?
Any suggestion would be appreciated.
Thanks in advance!
I have a spring based application which does authentication and authorization(oauth2 based) for a client app.I want to now use keycloak to manage my authorizations, but i want to keep my spring code. Basically i want to use my existing auth code as an external identity provider in keycloak.
I am thinking of adding changes in client app such that it receives token from my existing oauth code(which does the authentication) and then exchange this token with keycloak(for session and authorization management). How can i do this? What configurations need to be done in keycloak?
I read about token exchange in keycloak here, but i am not clear about the kind of token i need to send from my existing auth code.
https://www.keycloak.org/docs/latest/securing_apps/
Here is how OAuth2 roles are usually spread:
Keycloak is authorization-server
Spring service is resource-server
front-end is client
user is resource-owner
I have a doubt of you wanting your Spring service to be "authorization-server" as well (serve user identity). If so, I think you should not.
Keycloak (or any other OpenID provider) should be the only authorization-server. Both Spring and client(s) should be configured to use it as so.
To write it differently, Keycloak is responsible for users login and emitting tokens with user ID (subject) and rights (roles or whatever). Other tiers in the architecture (clients & resource servers) get user info from the token and apply relevant security checks (spring security annotations, Angular guards, etc.).
I published a mono-repo for a meetup with minimal sample involving a Spring resource-server and Angular (with Ionic) client talking to a Keycloak OpenID authorization-server. You might find some inspiration browsing it.
We have Api gateway in front of auth-provider and microservices(resource servers).
In this architecture, we don't need to get the JWT by authorization_code grant type and fire two calls as we don't have external oauth clients and only client is the gateway.
There is a sample app implemented by Joe Grandja for implementing oauth with cloud spring and Api-Gateway. That is awesome but, it is working based on web-session and authorization_code grant-type.
What it means is, stateful pattern, between browser and Gateway we have JSESSIONID and active server side session in the gateway and using the session between Gateway and Auth-Provider(UAA) to store Authorization Request to get code and then token.
I don't know what is the point here to have active sessions and use authorization_code when both auth_provider and its client (gateway) are in the same domain.
The design I am thinking, is based on fully stateless pattern. Browser or mobile apps should send token for each request in the header. We get rid of cookie based authentication and CSRF could be disabled and ... also gateway doesn't need to allocate memories for session objects.
We can have multiple Auth-provider instance with single Gateway if we want and etc.
There shouldn't be any problem to implement this from scratch, but I am wondering if Spring OAuth2 support implicit grant type when we are using:
NoOpServerSecurityContextRepository.getInstance()
The default SecurityContextRepository in the Spring is WebSessionServerSecurityContextRepository and in the sample app that I mentioned above, when I changed this to NoOpServerSecurityContextRepository I am getting exception because grant type is 'authorization_code' and spring needs to store request in the session.
So, I am looking to find a implementation for implicit grant type in spring.
Thanks,
I want to use Keycloak in a microservices based environment, where authentication is based on OpenID endpoints REST calls ("/token", no redirection to keycloak login page), a flow that I thought of would be something like this:
1. Front-end SPA retrieves the tokens from the "/token" endpoint and stores in browser's localStorage, then sends it with every request.
2. Gateway-level authentication: Acess Token is passed from the front end to the gateway, gateway consults Keycloak server to check if the token is still valid (not invalidated by a logout end-point call).
3. Micro-service based authorization: Acess Token is passed from the Gateway to the microservices, using Spring Boot adapter the microservices check the signature of the token offline (bearer-only client?) then based on the role in the token do the authorization.
My questions are: Does this flow make sense or can you suggest another flow? What type of Keycloak clients to use? What's an ideal way to pass Tokens using Spring Boot Adapter, and should it be done like that in the first place? Please keep in mind that I am not a Keycloak expert, I've done my research but I still have doubts.
Your Front-end SPA should be public-client and springboot micro service should be Bearer only Client and Gateway could be Confidential Client.
You can check the Keycloak provided oidc adapters. For springboot you use the keycloak provided adapter
Similar solution using api gateway is discussed here
I have read some articles for Keycloak spring implementation (eg: easily-secure-your-spring-boot-applications-with-keycloak) but no one mention how to use with JWT.
I have created zuul api gateway and add Keycloak adapter as described in the previously linked article. That's ok, but I want to use JWT with keycloak.
Mentioned elsewhere set the client access type to bearer-only and the session strategy to NullAuthenticatedSessionStrategy. That's enough or need something else for JWT?
So my questions:
How do I configure client on Keycloak admin for JWT?
How do I configure Keycloak in backend config file for JWT?
How do I configure Keycloak adapter for JWT?
How do I pass user info to microservice? Create filter in gateway? But how I get user info from request?
Keycloak access token is a JWT. It is a JSON and each field in that JSON is called a claim. By default, logged in username is returned in a claim named “preferred_username” in access token. Spring Security OAuth2 Resource Server expects username in a claim named “user_name”. So, you need to create mapper to map logged in username to a new claim named user_name.
In order to provide access to client (micro-service), respective role needs to be assigned/mapped to user.
In your spring boot application, then you need to configure connection to keycloak server, providing, auth url, token url, scope, grant-type, client-id and client-secret.
Afterthat, your app be able to parse JWT token, you need to create some JwtAccessTokenCustomizer. This class should extend DefaultAccessTokenConverter and implement JwtAccessTokenConverterConfigurer classes. The main logic lays in public OAuth2Authentication extractAuthentication(Map<String, ?> tokenMap) method.
Then you need to configure OAuth2 Resource Server to provide access for other micro services. For that you define here - Oauth2RestTemplate Bean.
And in the end, secure your REST API, via the standard configuration Component.
So, you can see that, it is a large work, and couldn't be described with code, show some of your work, divide it to the chunk, and ask interesting your questions.