I'm trying to convert a Stripes web app to Grails. The Stripes app uses Spring Security, but I would like the Grails app to use the Spring Security Grails plugin.
The app already has User and Role (Java) classes that I need to reuse, i.e. I cannot use the Grails domain classes that the s2-quickstart script generates.
The Spring Security plugin docs describe how to use an existing User domain class. The steps seem to be:
define a UserDetails implementation that reads from the existing User domain class
define a custom UserDetailsService implementation that returns instances of (1)
register an instance of (2) as a Spring bean named userDetailsService.
However the docs don't provide any information about how to use an existing Role class and the class that represents the many-to-many relationship between User and Role.
What other steps are necessary to use existing Role, User, and UserRole classes with the Grails Spring Security plugin? Is there any reason for me to run the s2-quickstart script if I don't want to generate any domain classes?
Follow-Up Questions to Burt's Answer
In the end, what you need is a new GrailsUser
Presumably GrailsUser here refers to the custom UserDetails implementation? In my case I'll probably just implement the interface directly. Does something like this seem reasonable?
class UserAdapter implements UserDetails {
private String password
private Collection<GrantedAuthority> springRoles
UserAdapter(User user) {
this.password = user.password
Collection<Role> roles = // load legacy Role objects
this.springRoles = roles.collect { new GrantedAuthorityImpl(it.authority) }
}
// If using password hashing, presumably this is the hashed password?
String getPassword() {
password
}
///////// other UserDetails methods omitted
Collection<GrantedAuthority> getAuthorities() {
springRoles
}
}
I'm not storing the whole User object within UserAdapter because of your warning about storing a potentially large object in the HTTP session.
what you need is.....and a List of GrantedAuthority instances (and the id if it's a GrailsUser)
If I use my own UserDetails implementation as above, then presumably I can ignore this comment about providing an id?
Finally, if I follow the approach outlined above, should I set these properties in Config.groovy and do I need to run the s2-quickstart script (or any others)?
Keep in mind that Spring Security doesn't care where the data comes from, it just needs a UserDetails instance when authenticating with the DAO auth provider and it can come from anywhere. It's convenient to use domain classes and database tables, but it's just one approach. Do what works for your data. In the end, what you need is a new GrailsUser (or some other impl) instance with the username and password set, the 3 booleans set, and a List of GrantedAuthority instances (and the id if it's a GrailsUser).
The simplest thing to do when you have legacy user and role data is to create a custom UserDetailsService. Use GORM, raw SQL queries, whatever you need to get the required data.
Another option is to write your own AuthenticationProvider like Glen did here: http://blogs.bytecode.com.au/glen/2010/01/15/hacking-custom-authentication-providers-with-grails-spring-security.html - although that's a larger solution that also involves a custom filter which you wouldn't need. The DAO provider uses a UserDetailsService but it's fine to create your own that combines the functionality into one class.
It's not a good idea to reuse your User domain class as the UserDetails though. Even if you implement the interface, you'd be storing a disconnected potentially large (if there are attached collections) object in the HTTP session. The POJO/POGO implementations (Spring Security's User class, the plugin's GrailsUser class, etc.) are very small and just a few Strings and booleans.
within the config.groovy file you have to specify your domain classes to use:
grails.plugins.springsecurity.userLookup.userDomainClassName = 'your.package.User'
grails.plugins.springsecurity.userLookup.authorityJoinClassName = 'your.package.UserRole'
grails.plugins.springsecurity.authority.className = 'your.package.Role'
i thinks it's not neccessary to implement your own userDetail service, because spring security uses
SpringSecurityUtils.securityConfig.userLookup
method to determine the domain class you configured before. your domain classes must provide the required fields and relations.
Related
I'm building an OAuth2 authenticated app using Spring Boot, following this tutorial: https://spring.io/guides/tutorials/spring-boot-oauth2/
At one point, the endpoint /user sends back the currently logged in user.
The guide warns by saying:
"It’s not a great idea to return a whole OAuth2User in an endpoint since it might contain information you would rather not reveal to a browser client."
But it doesn't give any more information - what type of information should I not be revealing to a browser client?
Thanks!
In Spring Security 5.x, the OAuth2User is a specific OAuth2AuthenticatedPrincipal (very similar to a UserDetails but without any notion of a password). Even without a password, exposing it can (and often will) leak sensitive information, implementation details of your authentication scheme, etc. You can expose it if you choose, but the warning in the guide is suggesting that care should be taken so as not to expose anything considered sensitive, and you should consider alternatives before exposing it directly.
For example, you might consider creating a CustomUser class that is populated from claims on the OAuth2User using a custom OAuth2UserService (various examples in the advanced configuration section of the docs). You can also take various steps to decouple the representation of an oauth2 user in Spring Security from the representation of a user in your application (e.g. by using #AuthenticationPrincipal to resolve your own custom user or access claims). If the application itself does not need a custom user, you can simply map claims of the OAuth2User to a response in your custom endpoint, as demonstrated in the guide.
Finally, you can combine all of these techniques to make your /user endpoint a "one liner" again, as in:
#Target({ElementType.PARAMETER, ElementType.TYPE})
#Retention(RetentionPolicy.RUNTIME)
#Documented
#AuthenticationPrincipal(expression = "customUser")
public #interface CurrentUser {}
#GetMapping("/user")
public CustomUser user(#CurrentUser CustomUser customUser) {
return customUser;
}
I want to implement the login/logout (authentication/authorization) system of my Spring 4 MVC application with Spring Security.
Currently I use a very simple hand-made implementation which basically does nothing more than comparing the entered username and MD5 hashed password with the database values by looking up the user by the username using a custom service method and comparing the encrypted passwords.
If the passwords match, the username of the logged in member is saved in the session and a ControllerAdvice looks up the Member object for the user using the username in the session prior to each request. The checkLogin method returns true is username and password match:
#Service("loginService")
#Transactional
public class LoginServiceImpl implements LoginService {
private MemberDao dao;
//more methods
#Override
public boolean checkLogin(String username, String password) {
String hashedPassword = getPasswordHash(password);
return dao.checkLogin(username, hashedPassword);
}
}
This does work but is not a very elegant solution, does not handle different roles and is probably not very secure. Besides I want to become familiar with Spring Security.
Reading the official tutorial for Spring Security (http://docs.spring.io/spring-security/site/docs/4.0.4.RELEASE/reference/htmlsingle/#tech-userdetailsservice) the way to go to authenticate against the Login service method does not become clear to me.
The tutorial discusses authentication direct against the database but I cannot find anything about using a Service method to perform the authentication and in my layered architecture, the database is hidden behind the Servoce and Dao (Hibernate) layers.
Also most examples in the tutorial use XML based instead of Java based configuration which I use for my application.
After having search a lot with search engines, I still have not found a tutorial which implements Spring Security in a Spring MVC application using a familiar layered structure using a Service and Dao layer.
Do I need to bypass Service and DAO/Hibernate layers and authenticate directory against the database? Or write a custom authentication-provider implementing UserDetailsService as described in this post?
Spring Security 3 database authentication with Hibernate
And is configuring Spring Security possible with Java based configuration only? I am a bit lost with this issue so I hope for some hints...
I'm going to implement a custom authorization based on ([User<-->Role<-->Right]) model and Rights should be compared to controller and method name (e.g. "controller|method").
I used customizing UserDetails and AuthenticationProvider to adjust granted authority (here), but as checked source codes and docs about how customizing the compare of authority I found there is a filter SecurityContextHolderAwareRequestWrapper) that implements isGranted and isUserInRole to compare authority, while the documents say using AccessDecisionManager voters to customize (As I understood). Which one should be used ? Where I have controller and method(action) name to compare authority with them ?
I got confused about Spring security a little. Is there any other resource than official docs that illustrate how it works, I mean sequence of actions and methods and how customize them.
There are several approaches:
Role based, where you assign each user a role and check the role before proceeding
Using Spring security expressions
There is also a new spring acl components which lets you perform acl control on class level and are stored in a database.
My personal usage so far has been 1 and 2, where you only assign roles to users.
But option 3 allows you to create finer grained security model, without having to rebuild your webapp when chaning the security model
Role Based
A role based security mechanism can be realised implementing the UserDetailsService interface and configuring spring security to use this class.
To learn on how to such a project can be realized, take a look at the following tutorials:
Form based login with in memory user database Link
Form based login with custom userdetails service Link
In short spring security performs the following behind the scenes:
Upon authentication (e.g. submitting a login form) an Authentication Object is created which holds the login credentials. For example the UsernamePasswordAuthenticationFilter creates an UsernamePasswordAuthenticationToken
The authentication object is passed to an AuthenticationManager, which can be thought of as the controller in the authentication process. The default implementation is the ProviderManager
The AuthenticationManager performs authentication via an AuthenticationProvider. The default implementation used is the DaoAuthenticationProvider.
The DaoAuthenticationProvider performs authentication by retrieving the UserDetails from a UserDetailsService. The UserDetails can be thought of as a data Object which contains the user credentials, but also the Authorities/Roles of the user! The DaoAuthenticationProvider retrieves the credentials via its loadUserByUsername method
and then compare it to the supplied UsernamePasswordAuthenticationToken.
UserDetailsService collects the user credentials, the authorities and builds an UserDetails object out of it. For example you can retrieve a password hash and authorities out of a database. When configuring the website url-patterns you can refer to the authorities in the access attribute. Furthermore, you can retrieve the Authentication object in your controller classes via the SecurityContextHolder.getContext().getAuthentication().
Furthemore to get a better understanding of the inner workings of these classes you can read the javadocs:
UserDetails - how the user credentials are stored and accessed
AuthenticationManager.authenticate(..) - contract on how AuthenticationExceptions are handled
UserDetailsService.loadUserByUsername(..)- contact on how username lookup failures are handled, e.g. user does not exist
Spel
Instead of checking authorities, SPEL enables you also to check other properties of a user.
You can use these in the URL patterns, but also annotate methods with #Preauthorize.
This way securing the business layer is less intrusive.
ACL Based
The ACL based model was introduced in spring security 3.0, but hasn't been well documented.
Their suggestion is to look at the Contacts XML example, since this one uses their new acl component.
Last this book contains great examples on how to further customize your security wishes.
I am using a service layer with repository pattern. The controller has a dependency on the service layer, and the service layer has a dependency on the repository.
I have to pass logged in user information to the repository layer for authorization purposes and am trying to determine the best approach for injecting the user information into the repository considering that I seem to have an extensive injection chain:
controller -> service(s) -> repositories -> logged in user info.
I guess the easy approach would be to pass the user information to the service methods that get called(i.e. FindById(int primaryKey, User currentUser), etc.)
But this seems very limiting and problematic down the road as opposed to injecting the User information.
What is the recommended approach to this problem?
I am a little confused about how the person in the article seems to be implementing the ICurrentUserFetcher. I assume that is would provide the extra properties that are not available from the IIdentity, but the article does not make this very clear.
class GenericRepository<T>: IRepository<T> {
private readonly ICurrentUserFetcher currentUserFetcher;
public GenericRepository<T>(Func<IIdentity> currentUserFetcher) {
this.currentUserFetcher = currentUserFetcher;
}
public void Update(T entity) {
var currentUser = currentUserFetcher();
...
}
}
var repo = new GenericRepository<Person>(() => HttpContext.Current.User.Identity);
Assign the user information to the current principal after the login. Google about IPrincipal and IIdentity. Those two classes are the built in way in .NET to handle the currently logged in user.
To access the user simply use Thread.CurrentPrincipal.Identity. I would however not use that property in the repository, but only in the service class. The reason to tha this that the repository should not be in charge of telling which user to fetch information for.
To assign the user on every request you have to use the PostAuthenticate event in global.asax.
I've been looking into using Spring Security for the authentication/authorization of my web application (this will be JDBC based).
However, a core component seems to be left out from my perspective. How do I register/create new users? Is there an out of the box API for that?
Do i need to write user registration and management from scratch?
Things i need to do include:
- Registering a new user
- Resetting passwords
- Emailing a user to activate their account
- Emailing a user to reset their account.
Thank you in advance.
I use Spring Security on my project. The framework does not have an API for user creation or registration as you asked. For Spring Security to be generic and usable across multiple frameworks, it can only take you so far before you have to write custom code. You can't really get a more specific answer about a framework or tool to use because at this point you will just use the frameworks you are already using anyway.
If you've set it up to use users and roles in your database, from your data access layer you would create a record in the user table or update a password (preferably stored as a hash) in that record. And as Aravind said, Spring does provide email support.
If you really want to see one way to do it: I'm using Spring MVC, JSP, and Hibernate. I use Spring's form tags in a JSP to bind a new user form to a Person object, and my controller method passes that Person object to my Dao to persist it.
The controller method signature looks like this...
#RequestMapping(value = "/newUser", method = RequestMethod.POST)
public ModelAndView createNewUser(final #Valid #ModelAttribute Person user,
final BindingResult result,
final SessionStatus status,
final #RequestParam(value = "unencodedPassword", required = true) String password) {
...
user.getRoles().add(new Role(user, Role.APPLICATION_ROLE.ROLE_USER));
userDao.createNewUser(user);
...
}
and my PersonDao would use Hibernate to persist the user like so
#Transactional
public void createNewUser(Person user)
{
Session session = sessionFactory.getCurrentSession();
session.save(user);
session.flush();
}
Have a look at my answer here.
"I have implemented a JAVA project for this use case. It is open
source, based on Spring-Security. A release version is on
Maven-Central, so you do not need to compile it, but instead you can
fetch it as maven-dependency to your project!"
<dependency>
<groupId>com.ohadr</groupId>
<artifactId>authentication-flows</artifactId>
<version>1.5.0-RELEASE</version>
</dependency>
As far as I know, Spring Security does not have built in support for new user creation and registration. You will have to manage this yourself. However it does have emailing support. Check here for more on this.