Spring security based application having both form login and SSO - spring-security

I have searched enough but I haven't got a clear answer and thus posting this question.
I have an existing application which uses spring security for authentication.
Current implementation uses a custom implementation of UsernamePasswordAuthenticationFilter for doing this.
Thus the flow is something like below(in very simple terms):
inputrequest>DelegatingFilterProxy>LoginUrlAuthenticationEntryPoint>CustomUsernamePasswordAuthenticationFilter>AuthenticationManager>CustomAuthenticationProvider
Now I have a requirement to implement SSO (since the user is already asusmed to be authenticated) in some scenarios.
The requirement states that if I have a specific request parameter present then I need to automatically authenticate the request without bothering about user/password.
So it is same set of resources and I do not have to authenticate user/password if the specific SSO related request parameter is present.
e.g
suppose a resource \test\bus is a secure resource.
if I come from normal way then we need to check if the user is authenticated or nor and force user to put valid user/password
if I come from SSO channel then I need to show the \test\bus resource as the user is already authenticated.
currently all the access restrictions are put through <http> element
e.g the snippet of security-config.xml is as follows:
Query: What options do I have in this case. I can think of below options:
Pre-authenticate the user before spring security framework kicks in. This will mean creating an authentication token and putting in spring context before spring security filter is called. This can be done through another filter which is called before spring security filter chain. I have tested it and it works.
Create another custom security filter which set-up the authentication token. I am not clear if this is correct approach as not sure when do we create multiple custom security filter
Create another custom authentication provider e.g SSOCustomAuthenticationProvider. This provider will be called in the existing current flow as we can have multiple authentication providers to a authentication manager. The only issue is that in order to achieve this I have to change the request url to authentication filter's target url so that spring security doesn't check for authentication.
to explain more,
let's say request uri is /test/bus, I will write a filter which will intercept the request and change it to /test/startlogin. This is currently my CustomUsernamePasswordAuthenticationFilter's target url i.e
<property name="filterProcessesUrl" value="/test/startlogin"/>
The flow will be
inputrequest>DelegatingFilterProxy>LoginUrlAuthenticationEntryPoint>CustomUsernamePasswordAuthenticationFilter>AuthenticationManager>SSOCustomAuthenticationProvider
I have tested this and this works. Is this a valid approach or a hack.
Is there any other viable option available with me.
Thanks for reading this.

Related

How to implement multiple authentication methods in Spring WebFlux Security?

I'd like to provide two ways to authenticate in my application, one is basic auth (users), and the other is some kind of token based (technical users). I understand that I need a custom ReactiveAuthenticationManager but I can't find clues on the big picture. (Actually, there are a very few insights for MVC, and none for WebFlux.)
1) How do I populate the Authentication's name and credentials in the token based approach? If I configure Spring Security to use httpBasic it's already populated. Some kind of filter needed?
2) How do I distinguish in the authentication manager where the credentials are coming from? Do I have to lookup in the userRepository and (if not found) in the technicalUserRepository too?
3) Do I have to override the SecurityContextRepository? All the tutorials do it but I don't see any reason to do so. What is it exactly? This source states that "SecurityContextRepository is similar to userDetailsService provided in regular spring security that compares the username and password of the user." but I think he means ReactiveUserDetailsService (neither UserDetailsService nor ReactiveUserDetailsService does that by the way, it's just for user lookup).
Since i am decent at Webflux and i have worked a lot with oauth2 i'll try and answer some of your questions.
1) How do I populate the Authentication's name and credentials in the
token based approach? If I configure Spring Security to use httpBasic
it's already populated. Some kind of filter needed?
A token never contains credentials. A token is something you get issued after an authentication has been done. So usually you authenticate against an issuing service. After you have authenticated yourself against that service you will be issued a token.
If its an oauth2 token the token itself is just a random string. It contains no data about the user itself. When this token is sent (using the appropriate header) to a service using spring security. Spring security has a token filter that will basically check that the token is valid, usually by sending the token to the issuer and asking "is this token valid?".
If using a jwt, its different, the jwt must contain some information like issuer, scopes, subject etc. etc. but its basically the same thing, there is a built in filter that will validate the jwt by sending it to the issuer (or using a jwk that the service fetches from the issuer so it can verify the integrity of the jwt without doing an extra request).
2) How do I distinguish in the authentication manager where the credentials are coming from? Do I have to lookup in the userRepository and (if not found) in the technicalUserRepository too?
You don't You usually define multiple SecurityWebFilterChains for different url paths. I have not done this in Webflux Spring Security, but thats how you do it in regular Spring Applications, and i don't see any difference here. Unless you are doing something crazy custom.
3) Do I have to override the SecurityContextRepository? All the tutorials do it but I don't see any reason to do so. What is it exactly? This source states that "SecurityContextRepository is similar to userDetailsService provided in regular spring security that compares the username and password of the user." but I think he means ReactiveUserDetailsService (neither UserDetailsService nor ReactiveUserDetailsService does that by the way, it's just for user lookup).
The answer here is probably no. You see Spring security 4 had very bad support for oauth2 and especially JWT. So people got accustomed to writing their own JWT parsers. When spring Security 5 came, Spring implemented a jwt filter that you can configure and use built in. But there are a lot of outdated Spring Security tutorials out there and foremost there are a lot of developers that don't read the official documentation.
They mostly google tutorials and get the wrong information and then work on that.
But easy explained:
SecurityContextRepository
If you have session based authentication (server establishes a session with a client) it will store the SecurityContext (session) in ThreadLocal during a request. But as soon as the request ends, the session will go lost unless we store it somewhere. The SecurityContextPersistenceFilter will use the SecurityContextRepository to extract the session from ThreadLocal and store it, most common is to store it in the HttpSession.
AuthenticationManager
Override this if you want to do a custom authentication process. Example if you want to validate something, call a custom LDAP, database, etc etc. It\s here you perform you authentication. But remember, most standard logins (like ldap, sql-servers, basic login etc.) already have prebuilt configurable managers implemented, when you select what login type like .httpBasic() you will get a pre-implemented AuthenticationManager.
UserDetailsManager
You override this when you want create a custom UserDetails object (also usually called Principal) In the UserDetailsManager you do you database lookup and fetch the user and then build and return a UserDetails object.
Those two interfaces are the most regular custom implementations, and are used if you need to to basic authentication/session based authentication.
If you wish to do token, you have to think about, who is the token issuer? usually the issuer is separate and all services just get tokens and validate them against the issuer.
I hope this explains some of the questions. I have written this on the bus so some things are probably wrong and not 100% correct etc. etc.

How to add additional custom criteria for authorization or token creation in Spring Oauth?

We have implemented Spring Oauth authorization+resource server that can be used for external applications.
Now we would like to add custom checks before some oauth calls returns in the authorization server, most importantly for the authorization code but also before allowing returning a token sometimes.
An example use case might be that which users that are allowed to login for a specific client_id might vary and if not allowed this should generate a redirect back with an error.
So for example a user might trigger a login from a third-party app, redirected to our authorization server and shown a login page, however after login it is discovered (through our business logic) that this specific user is not allowed to authorize access to that specific app/client id.
What is the best way to achive this result in a way that is consistent error handling in Spring oauth?
Also, a related question is also how to resolve the client details before the login screen shown so more specific client details can be shown when logging in?
We could parse the client_id parameter manually but maybe there is a more elegant way to hook into Spring oauth to solve this?
(sorry for dual question but its sort of related and the first question is the most important one)

How do the AuthorizeFilter and Authentication methods work under the hood?

I would like to understand briefly how the authorize filter and FormAuthentication.SetAuthCookie work under the hood. It's the only thing I find ambiguous after reading some books on the language.
I don't understand how the authorize filter knows where to look. And what about FormsAuthenticationTicket VS FormAuthentication ? And is cookie the most secure way, I mean I'm sure it's possible to export the cookie from a browser and use it somewhere else..?
You might find this question helpful.
If you're interested in how the Authorize filter works in more detail you can review the source code: AuthorizeAttribute
Briefly the Authorize filter will check whether the user has been authenticated by checking the HttpContext.User.Identity.IsAuthenticated property. The User property will have been set by the FormsAuthenticationModule in the case of Forms Authentication.
The FormsAuthentication.SetAuthCookie method creates a ticket for the authenticated user (assuming the user has provided the correct credentials) and adds it to the cookies collection of the response. Alternatively the module can be configured to use cookieless authentication if you want but the encrypted ticket is still sent with each HTTP request. Either way the client (browser) needs a way of telling the server that the requested is authenticated.
Regarding your concerns over security there are some ideas in this question.

Using a Custom Single Sign On Authentication Service with Spring Security Core Plugin

I'm working on a Grails application and want to integrate with a custom single-sign-on service (not CAS, but similar). I'm struggling to find all the pieces that I need to customize to make this happen. Can someone explain to me a general outline as to what I need to use to accomplish this? I've read the documentation on the plugin, but it assumes I know which beans to override and where to put all the needed files.
I've block-quoted what I think needs to be done based on my research below each point.
Order of Operations
1- The user requests secure content (everything is secure in the application for now)
I believe this setting is in the Config.groovy file:
grails.plugins.springsecurity.rejectIfNoRule = true
grails.plugins.springsecurity.securityConfigType = "InterceptUrlMap"
grails.plugins.springsecurity.interceptUrlMap = [
'/**':['ROLE_ADMIN']
]
2- Spring Security checks to see if the user has a specific value set in a cookie provided by the authentication service
I'm guessing I need to create an authentication filter, but I don't know where to put it or what it should look like.
If they don't, the user is redirected to this custom SSO service, they login, once authenticated, the user is redirected back to my application (with a new cookie set)
3- Spring security checks for the cookie value and validates it against the custom service (via HTTP POST)
From some research, I think that I need to use PreAuthenticatedProcessingFilter, but I haven't been able to find any examples of how to do this.
4- The custom service returns a series of name/value pairs, a user then needs to be created in the local application database (or the timestamp of "lastLoggedIn" is updated if they user's data is already in the database)
I believe this is done in the same PreAuthenticatedProcessingFilter as number 3 or in a GrailsUserDetailsService
5- The user's authentication is cached in the session for a period of time (6-8 hours) so that re-validation against the SSO service doesn't need to occur every time the user requests a new resource.
I'm not sure if this is something that's done inherently or if I need to add code to do this (and also set the session timeout)

External authentication using Spring Security

We got our own central session management. Generally user can authenticate over it with an username and password, and as a result he gets an session_id. All other operations are done with that session_id. Let's say that the session management is accessed by a XML RPC.
I have two cases to implement:
Central web application made in Spring, which has login form
External web applications also made in Spring, which are relying on
passed session_id only.
Few more notices regarding system:
- session_id is stored in a cookie (after successful login, I have to add cookie to a response)
- every page request has to check session_id validity in session management system
I'm quite new to Spring, so I'm struggling to understand where and how to implement my custom logic.
My questions are:
What parts of a system I have to implement to have my own login
logic (got to have access to a response object too - to set cookie)?
I tryed something with extending UsernamePasswordAuthenticationFilter and implementing my own
AuthenticationManager, but I'm not sure that I'm going the right
way.
Is there point where/how can I implement my "every request session
check" in Spring Security manner?
session_id is stored in a cookie (after successful login, I have to add cookie to a response)
Do this in a AuthenticationSuccessHandler that is configured into your <form-login> element:
<form-login authentication-success-handler-ref="authenticationSuccessHandler"/>
External web applications also made in Spring, which are relying on passed session_id only.
Create a new filter where you check for the session_id cookie. If the cookie is not present or if it is invalid redirect to the central web application for the user to log in. If the cookie is present and valid and the user isn't already authenticated then create a new Authentication and add it to the SecurityContextHolder.
Take a look at RememberMeAuthenticationFilter.doFilter() for an example of what you want to do in your filter.
Add this filter to the filter chain using the <custom-filter> element.

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