Spring security - CSRF with REST methods - spring

I have a rest api where I have exposed get, post, put and delete methods. I am using spring security and implementing basic authentication. I am allowing the GET request to be made by a user with the role USER whereas the other requests can only be made by a user with role ADMIN. I see that if I don't add the crsf().disable() line only the GET method works correctly, whereas I get a 403 Forbidden for other methods. However when I add csrf().disable() all the methods work fine. Is this expected or am I doing something wrong?

When csrf is enabled , springboot expects you to send the csrf token with every request that is made to the endpoint. If that is not included then the request is denied and you get the 403 response code. It is like an HTTP session. But rest endpoints are stateless so it's better not to use csrf with it . Rest endpoints are essentially immune to csrf attacks as they are stateless.Read doc.

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Securing rest and actuator endpoints using custom token and http session

I have a spring boot app where the API #Controller endpoints are secured using a token that is contained in the http header. The token needs to be extracted from the header and validated against an internal cache to make sure it is valid. If the token is valid then the request can proceed to the controller and if it is not valid then it should return a 401 to the caller.
I also have another requirement to secure some of the actuator end points. When the user tries to use the browser to access the respective actuator endpoint, it will check for a user session if no session exists then the request is redirected to the spring login page. When they login I need to extract the username and password and validate using an external service. If valid a session can be created for the user and they can then use the hawtio endpoint. The session needs to store role based information so that when the user tries to perform JMX operations it will only allow them to perform the appropriate read only / write if they have the requisite role.
Any pointers regarding how you'd try and tackle this would be most welcome. I am unsure whether this is achieved by specifying addFilterBefore or addFilter and I don't understand how having authenticated the user for the actuator I go about creating a session that can be stored in the context and checked later on for subsequent requests.
Thanks

Regarding Cross site Scripting Forgery

I am working on csrf and using spring 5. Spring 5 automatically provide supports for csrf and on enabling csrf protection on the server side I am getting
403: Invalid X-CSRF token
So this means a token needs to come from frontend?
My understanding is that backend generates csrf token and sends as a response to frontend browser and then it uses this token and send it as cookies to the backend server and then backend will validate it. is my understanding is correct?
when manually generating the hidden token for csrf, How backend will know it is a valid csrf token?
Second Scenario: Suppose two users are logged in to my website and frontend is sending this token to backend then how the application will differentiate which token is for which user?
Also please explain how it works internally means we enabled csrf protection in the backend and manually generated a token on the front end then what it does behind the scenes?
consider my frontend is JS pages
Is there is any specialty of Spring 5 which take care's of sessions for each user and validate tokens automagically for each user?. I tried finding it on the official website but didn't get it anywhere
Hi Zaib the csrf token is generated from back-end as you stated, once it is generated is automatically sent to the front-end which must take care to retrieve from the model and re-post for each "POST" requests.
You can share the csrf token via different way mostly i used header or html parameter.
A token is related to a specific session so is not really important if you have a logged user or not , even not authenticated users must send the csrf token for "POST".
The csrf token is validated via a filter placed in the front of the filter chain defined by Spring security itself, if you search in the documentation there is a table showing you the position of each "default" filter enabled by Spring security. Moreover if you enable debug on Spring ( </debug> is enough in your xml configuration) you will have printed all the filters used while processing an http request.
So each time a request with "POST" method pass through that filter , it will check if in the parameters there is the csrf token or header.
I never used as cookie so it may a different case for you if specifically need that but it does not differ on how it works.
Here is the details of csrf implementation on Spring:
https://docs.spring.io/spring-security/site/docs/5.0.7.RELEASE/reference/htmlsingle/#csrf-configure
I said "POST" method but actually the token is checked for any method that is related to a change of state , you can refer to doc here:
https://docs.spring.io/spring-security/site/docs/4.2.5.RELEASE/apidocs/org/springframework/security/web/csrf/CsrfFilter.html
Hope this help clarifying a bit the usage of the csrf token.

How does spring basic authentication works for subsequent requests after login via basic authentication

I am implementing REST services using springMVC. Now i have added basic authentication entry point in my spring security file. But i don`t know that, Once user authenticated by passing credentials in Authorization header does he need to pass those credentials for all subsequent requests?
for example,
I have two URLs:
1) localhost/apppName/login
// Here user passes credentials in Authorization header. So, user authenticated successfully.
2) localhost/appName/getUsers/1
//Here, client need to pass those credentials in Authorization header?
if it is needed, then why spring kept prinicpal object in the SecurityContextHoder after authentication done via BasicAuthenitcationEntryPoint?
Clients of this services can be any thing like Android, java, .Net
Any suggestions will be appreciated.
Pure REST is stateless, which means that no client context is being stored on the server between requests. That means you need to send the Authorization header for each request.
You don't need to hit the login URL when using Basic auth, that's the point.
However, you can use sessions in combination with Basic auth, and in that case you should pass session cookie between requests. It may have some performance advantage, but generally I would not recommend it.

Spring Security - REST API - token vs. cookie

I have written a REST- API in Java and I have secured this API with Spring Security. The procedure is like this:
Frontend invokes /login RestService in Backend
Backend gives back token to frontend
at each REST- API Backend invokation the token has to be placed in header
This works fine, but I have read that it is also possible (with Node.JS/Passport.js/Express.js) that the session object with the cookie inside can be transfered out of the box without any custom code.
My question now would be if there is a better approach so that the frontend/client do not need to set the token into the header all the time for any request.
Usually token based authentication has advantages over cookie based.
You can achieve this using middle-ware layer
Here is a good Post - https://auth0.com/blog/2014/01/07/angularjs-authentication-with-cookies-vs-token/
Server side, I usually first check in the headers if there is an auth token. If not, I then check in the cookies as a fallback.
If you want to use cookies, then at your step 2, you need to add a Set-Cookie header to the response, so that browsers know they must store a cookie. Once done, no need to add a header client-side, since browsers will send cookies each request. You'll need to add a CSRF protection though (here is a good example).

Spring template connect to OpenSSO/JAAS secure endpoint

I'm trying to access a REST service via a server-to-server GET request that is secured by OpenSSO/Spring Security and am unable to. It's like my Spring Rest Template client is not stateful to hold the cookies it should as I get redirected through the authentication workflow.
When doing this with a browser, the initial request is redirected to OpenSSO, I'm challenged for my cert (PKI), I present it, get a response with my authentication cookie header. Then I am redirected back to my original destination, I present my auth cookie in the request header and I'm on my way.
This isn't happening in my server-to-server invocations.
I've searched for quite a while now and can't seem to find any solutions that hold onto this state across redirects!
Following the link in zagyi's comment may have worked, but I spent some more time and found the following solution, which does not involve overriding anything:
To handle the authentication cookie in the REST controller, you have to explicitly tell it to accept cookies. Before handling the call, add the following line of code:
CookieHandler.setDefault(new cookieManager(null, CookiePolicy.ACCEPT_ALL));

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