Using custom spring security annotations - spring

I'm trying to make use of springs security annotations like #PreAuthorize and #Secured but Im looking to evaluate a user not on a role but whether they have permissions to a particular entity in this case a firm. In my controller I receive a http request containing a firmId as a parameter and I want to make sure this user is permissioned to this firm. Is this possible using the current spring security annotations?. Im looking for an elegant solution, i've been looking at custom constraint validators as part of the jsr303 specification. Method header below.
public ModelAndView getSessionsJson(HttpServletRequest request,
HttpServletResponse response) throws ServletRequestBindingException {}

I think you can do something like this:
public ModelAndView getSessionsJson(HttpServletRequest request, HttpServletResponse response) throws ServletRequestBindingException {
Integer firmId = getFirmId(request);
Firm firm = getFirmById(firmId);
doSomeBusinessLogic(firm);
.....
}
#PreAuthorize("hasPermission(#firm, 'admin')")
public void doSomeBusinessLogic(Firm firm) {
....
}
....
using pre and post annotations in conjuction with ACL module. Of course before you need to set up ACL DB schema and prepare ACL permissions for each firm object.

Related

Spring boot - running check on every request and storing objects for lifecycle

I have a scenario where I need to run a few db checks at the start of every web request, and in the case of success I need to store objects for use later in the request by the controller, or in the case of failure I need to render an error page.
A very similar real world example would be a SaaS app checking and loading the account based on a vanity url, then storing the account for use by controllers to avoid multiple db requests.
What are the best ways to achieve this in a Spring boot app? I have experimented with Filters but I think an Interceptor might be better at the task, that covers running the check but what about storing the objects for later use? Is there a request lifecycle context of some kind that I can store against?
Spring supports request scope for beans. You can use them for storing data used during request execution.
In my experience, best way I've done similar stuff is through HandlerMethodArgumentResolver.
Basically imagine you have a custom type, let's call it UserContext where you store the information that's needed for the request. And you have a UserContextService let's say that has a method getUserContext(HttServletRequest), that is used to retrieve the context based on the request, from which you can call your database based on whatever request parameter/header/path-variable, etc. You can refine that as you need. But based on this simple assumptions, you can have a controller that looks like this:
#RequestMapping("/some/url")
public SomeResponse someMethod(UserContext userContext, ...) {
//do something here with UserContext
}
The way that Spring will inject this UserContext into your controller would be with a custom HandlerMethodArgumentResolver like this:
#Component
public class UserHandlerMethodArgumentResolver implements HandlerMethodArgumentResolver {
#Autowired
UserContextService
#Override
public boolean supportsParameter(MethodParameter parameter) {
return parameter.getParameterType().equals(UserContext.class);
}
#Override
public Object resolveArgument(MethodParameter parameter, ModelAndViewContainer mavContainer, NativeWebRequest webRequest, WebDataBinderFactory binderFactory) throws Exception {
HttpServletRequest req = (HttpServletRequest)webRequest.getNativeRequest();
UserContext userContext = userContextService.getUserContext(req);
if (userContext != null) {
return userContext;
} else {
return WebArgumentResolver.UNRESOLVED;
//Or throw exception
}
}
}
That you'll register by overriding the WebMvcConfigurer.addArgumentResolvers method in your WebMvcConfigurer bean/config-class.
This mechanism is the same used by #PathVariable, #RequestParam, etc...

Spring boot and checking HTTP header presence

I send along every REST call my custom header, which is (for instance) an authorization token. This token remains the same, as I do not need high security in this case. Can I use some simple way how to check every request coming to RestController whether it has this token among headers?
I can see a few ways:
Coding a #ModelAttribute in a #ControllerAdvice class, like this
#ControllerAdvice
public class HeaderFetcher {
#ModelAttribute
public void fetchHeader(#RequestHeader Optional<String> myHeader, Model model) {
if header is present
model.addAttribute("myHeader", the header);
else
throw exception
}
}
Haven't tried this, though.
Using a filter
Using AoP

How to generically authorize or validate a JSON rest request based on the authenticated user and an attribute of the requestbody

My current Spring3 REST JSON api is authenticated with the default InMemory properties file/basic-authentication authentication manager. That has worked fine thus far, but I need to further validate that an incoming request is allowed to be made for that user. The Role concept seems to work fine as a gateway for entry to a particular controller's url, but it doesn't go far enough to validate that the user is permitted to ask for the data being requested.
In my app, each B2B partner that will be making requests to the API is assigned an applicationId. That partner user account is only allowed to make requests for that applicationId. The applicationId is passed as an attribute of the RequestBody POJO for all the POST API messages. I would like to decline requests that are made for improper applicationIds.
How can I validate that the authenticated user is making a permitted request?
I've started down the path of creating a custom AuthenticationProvider, but I don't know how to get access to the applicationId within the RequestBody bean that hadn't been marshalled into the java bean yet.
Perhaps a custom AuthenticationProvider isn’t the right solution, and a request validator of some sort is needed. If so, how would the validator on the appId attribute get access to the Principal (authenticated user object)
With any solution, I would like it be invisible to the controller, so that requests that do make it to the controller are permitted ones. Also, ideally, the solution should not depend on an engineer to remember some annotation to make the logic work.
Thanks in advance,
JasonV
EDIT 1: By implementing an InitBinder in the controller, and using the #Valid annotation on the RequestBody I was able to validate a request. However, this is not the Droids (er I mean solution) I'm looking for. I need to find a more generic way to handle it without all those Binders and annotations; too much to remember and spread around the application over dozens of request controllers, and it will be forgotten in the future.
The usual way to implement this is using #PreAuthorize.
#PreAuthorize("hasRole('USER') and authentication.principal.approvedAppId == #dto.applicationId")
#RequestMapping...
public ... someMethod(#RequestBody Dto dto, ...)
If you're worried about the repetition of the SpEL, define a new annotation like #PreAuthorizeUser and set the #PreAuthorize as a meta-annotation on it.
I was able to utilize an aspect to solve the problem generically.
I would still like to see if it is possible to do the following:
Get a marshalled RequestBody from the request object in the context of an AuthenticationProvider.
Here is the aspect code for future help to others.
#Pointcut("within(#org.springframework.stereotype.Controller *)")
public void controllerBean() {
}
#Pointcut(
"execution(org.springframework.http.ResponseEntity *(.., #org.springframework.web.bind.annotation.RequestBody (*),..))")
public void methodPointcut() {
}
#Around("controllerBean() && methodPointcut()")
public Object beforeMethodInControllerClass(ProceedingJoinPoint jp) throws Throwable {
Object[] args = jp.getArgs();
long requestAppId = Long.parseLong(BeanUtils.getProperty(args[0], "applicationId"));
Authentication auth = SecurityContextHolder.getContext().getAuthentication();
User principal = (User) auth.getPrincipal();
String username = principal.getUsername();
long[] approvedAppIds = getApprovedAppIdsForUsername(username);
for (long approvedAppId : approvedAppIds) {
if (approvedAppId == requestAppId) {
isAllowedAccess = true;
break;
}
}
if (isAllowedAccess) {
return jp.proceed(args);
} else {
LOGGER.warn("There was an attempt by a user to access an appId they are not approved to access: username="+username+", attempted appId="+requestAppId);
return new ResponseEntity(HttpStatus.FORBIDDEN);
}
}

Read request attribute in a Jersey ContainerRequestFilter

I've got a Jersey API that's protected by Shibboleth, an SSO implementation. Shibboleth puts the id of the logged-in user in a request attribute. On the back end, I'm using Shiro for authorization. Shiro would like to know the logged-in user so it can load up permissions.
What is the correct way to get that userId out of the request attribute and into Shiro? Right now, what I'm trying is:
#Provider
public final class ShiroLoginFilter implements ContainerRequestFilter {
#Context
private HttpServletRequest request;
#Override
public void filter(final ContainerRequestContext requestContext)
throws IOException {
final String userId = (String) this.request.getAttribute("nameid");
final Subject subject = SecurityUtils.getSubject();
subject.login(new LocusAuthenticationToken(userId));
}
}
Unfortunately, due to JERSEY-1960, I can't inject the request context into a filter. Every user needs to "login" in order to load permissions. I'd rather not have to repeat the login code in every method of the API. I am also not permitted to use a web.xml filter (by my boss). Do I have any good option here?
You should also be able to obtain ServletRequest attributes directly from ContainerRequestContext via ContainerRequestContext#getProperty as described in the JavaDoc of the method:
In a Servlet container, the properties are synchronized with the ServletRequest and expose all the attributes available in the ServletRequest. Any modifications of the properties are also reflected in the set of properties of the associated ServletRequest.
Note: Injecting HttpServletRequest should work as expected since Jersey 2.4 (released in 10.2013).

How to evaluate a SpEL Security expression in custom java code?

i have come to need to invent a new type of annotations, one of fields of which would be a Spring Expression Language (aka SpEL) expression string.
After a bit googling and examining existing classes, i've figured out that the way of evaluating expression might be like this one (correct me if i am wrong in any way):
ExpressionParser parser = new SpelExpressionParser();
Expression exp = parser.parseExpression("isAnonymous()"); // well, this is only an example
SecurityExpressionRoot context = ... obtaining the instance of subclass of SecurityExpressionRoot ...
System.out.println(exp.getValue(context)); // just an example
But here is the problem: the most suiting for my case MethodSecurityExpressionRoot is package-local. There is even a task about making it public in Spring Security JIRA which didn't got any attention from developers for a year.
And even if it wasn't package-local, i still have a weak understanding of where to obtain objects for methods setTrustResolver, setRoleHierarchy and setPermissionEvaluator of SecurityExpressionRoot class, which seems to be needed for it's proper functioning.
So, my question is: how do you properly get the correct SecurityExpressionRoot-subclass instance and how to populate it with required objects?
I am solving same problem. I have a list of menu items. Each menu item contains a security expression string (SpEl). I tried to use #PostFilter("filterObject.securityExpression") but I couldn't figure out how to evaluate a SpEl string inside a SpEl string.
So I ended up with custom evaluator bean. Heavily inspired by org.thymeleaf.extras.springsecurity4.auth.AuthUtils
The evaluator uses same SecurityExpressionHandler as web security filters. This means its necessary to provide request and response for an evaluation context. But this shouldn't be complicated since Spring injects those values into controller methods.
Evaluator:
#Component
public class WebSecurityExpressionEvaluator {
private static final FilterChain EMPTY_CHAIN = (request, response) -> {
throw new UnsupportedOperationException();
};
private final List<SecurityExpressionHandler> securityExpressionHandlers;
public WebSecurityExpressionEvaluator(List<SecurityExpressionHandler> securityExpressionHandlers) {
this.securityExpressionHandlers = securityExpressionHandlers;
}
public boolean evaluate(String securityExpression, HttpServletRequest request, HttpServletResponse response) {
SecurityExpressionHandler handler = getFilterSecurityHandler();
Expression expression = handler.getExpressionParser().parseExpression(securityExpression);
EvaluationContext evaluationContext = createEvaluationContext(handler, request, response);
return ExpressionUtils.evaluateAsBoolean(expression, evaluationContext);
}
#SuppressWarnings("unchecked")
private EvaluationContext createEvaluationContext(SecurityExpressionHandler handler, HttpServletRequest request, HttpServletResponse response) {
Authentication authentication = SecurityContextHolder.getContext().getAuthentication();
FilterInvocation filterInvocation = new FilterInvocation(request, response, EMPTY_CHAIN);
return handler.createEvaluationContext(authentication, filterInvocation);
}
private SecurityExpressionHandler getFilterSecurityHandler() {
return securityExpressionHandlers.stream()
.filter(handler -> FilterInvocation.class.equals(GenericTypeResolver.resolveTypeArgument(handler.getClass(), SecurityExpressionHandler.class)))
.findAny()
.orElseThrow(() -> new IllegalStateException("No filter invocation security expression handler has been found! Handlers: " + securityExpressionHandlers.size()));
}
}
Usage as a controller method:
#ModelAttribute("adminMenuItems")
public List<AdminMenuItem> getMenuItems(HttpServletRequest request, HttpServletResponse response) {
List<AdminMenuItem> menuItems = ...
return menuItems.stream().filter(item -> evaluator.evaluate(item.getSecurityExpression(), request, response)).collect(toList());
}
I managed to achieve exactly this without any new annotations. The first thing you need to do is wrap your menu item in a sec:authorize tag, where the sec namespace is from spring security taglibs. We use:
<sec:authorize access="hasRole('${menuItem.permission}')"></sec:authorzie>
where ${menuItem.permission} is the permission field of the current menuItem object (we're looping through menuItems that we've retrieved from the server). The SpEl hasRole() is implemented by spring in the org.springframework.security.access.expression.SecurityExpressionOperations class.
That won't give you security though, it'll just make the gui nice. The server also needs to be secured with something like this:
#PreAuthorize("hasRole('...')")
The #PreAuthorize annotation is also from spring security, and it stops a client from executing a method on your server unless the user has the given role. To make this work we had to implement the org.springframework.security.cas.userdetails.AbstractCasAssertionUserDetailsService. A similar class exists for most identity management servers. We also had to implement org.jasig.services.persondir.support.ldap.LdapPersonAttributeDao, but we're using ldap too. YMMV.

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