The ability to add, update, and delete various entities in my application is often determined by the relationships defined between the various users involved. Here is an example:
A basic user or his supervisor can create tasks associated to the user, but only his supervisor can lock down the task so that the basic user will not longer be able to add/update/delete it. Until locked down, both individuals will be able to update the task.
What is the best approach to implement these kind of complex and advanced rules that deal with the relationship of users and the state of the entities (new, existing), as well as other things like maybe a user-defined status associated to the entity?
Thanks
What is the best approach to implement these kind of complex and advanced rules that deal with the relationship of users and the state of the entities (new, existing), as well as other things like maybe a user-defined status associated to the entity?
You want to use an authorization standard, namely XACML, the eXtensible Access Control Markup Language. XACML is:
a standard developed by OASIS, just like SAML is
a standard that focuses on fine-grained access control: access control that takes into account user information, resource information, state, and contextual information
a standard that implements the attribute-based access control (ABAC) model: the user information, resource data, and state can all be seen as attributes
a standard that uses policies and rules to structure the attributes and grant / deny access: XACML is policy-based
a standard that can be applied across multiple layers e.g. across the presntation tier, the data tier, the business tier of an MVC application
a standard that can be applied to multiple technologies and languages e.g. C# (MVC4 and more), Java, Python...
With XACML, you can easily implement relationships e.g.: an employee can approve a transaction if and only if the transaction amount < employee approval limit AND the transaction is not locked.
Where to go from here?
Check out NIST's page on ABAC.
Check out OASIS XACML's page and spec
Check out existing implementations (open-source and vendor such as the one I work for, Axiomatics.)
At a bank I worked for, we had a loan management system that allowed the entire bank hierarchy to see loans in their reporting structure. For instance, a Market exec could see the loan portfolio of all of his/her reports at once. Additionally, s/he had the ability to select from a list of all reports' (direct or indirect) names to view the portfolio of that employee.
It was complex, but we had to maintain an HR database of the reporting structure. Once we had that, we built user functions (could be done as stored procs, too, but user functions worked well in our LINQ to SQL backend) that allowed us to check whether user x supervises user y.
So, in your example, as long as you know who owns the task, and have access to a method that can be used to determine if the task owner reports to the currently-logged-in user, you should be able to easily enable/disable the "lock" button on the page.
The legwork lies in creating that reporting structure DB, and keeping it up to date!
Related
This is my first attempt, trying to integrate Membership on an existing shop already in production.
I'm not quite sure, based on my scenario, if I should use the build-in aspnet-providers or custom implementations of them in order to integrate membership.
Here's a few details:
I have a multi-tenant, single database, single schema web app based on subdomain.
The app is already in production and I will later want to link newly registered users with existing anonymous orders by email.
The development will continue after the membership integration, new features will be added, meaning new columns and linked tables for the users table.
This answer got my thinking of using the membership deafult Profile in order to extend the users table created by the aspnet providers, since I don't have users yet. Though its not clear to me how I would link Users with Orders and other tables/entities that might later be added when the app is going to be extended.
Maybe I could define my entities related to users as user-defined profile properties but they would not have associations on my database.
Another overhead I'm thinking of is how would I associate the users with the different tenants of the app. I would want users to be able to regiter in different tenants/subdomains with the same email.
How would you implement membership in this scenario?
This question is an aggregate of a few questions. I will try to answer them to he best of my knowledge
In case of managing users, i would like to suggest that you consider the following approach
Pre-define a list of basic user profile metadata that you will need in the application
Create an extensible approach like having custom fields for the user profile so that it can accommodate any data that may be required to capture in future
You should also be planning for a self-registration system in the application that will allow your user's to register themselves like the anonymuous ones that use the system with an email
Regarding associating the business entities, you will require to associate the entities with the tenant and not with the user. the level of application will be from the tenant and then it will flow down to the users.
Additionally, you should not have the user accessible business entities, when they are maintained in a form of package or so, it will be very easy to manage and use.
Share your thoughts on these approaches.
- Create a tenant identifier column [property] for each profile that identifies the base tenant to which the user belongs to
- create a table that manages the list of other tenant's that the user may be gaining access to at a later part
I'm trying to find the best way to handle a "complex" security / privacy system using Symfony2.
I read a lot of documentation about the ROLES and the ACLs but I'm looking for something different.
I need the rights to be calculated based on the properties of the objects.
In my case, I have a User object and multiple other objects (Project, Task, Label, and more...).
I need to check if a User can read or write any kind of object without storing the rights in the database (like the ACL system is doing). The rights should be "calculated" based on the relation between the User and a given object.
For example, the User(1) can write on the Task(2) because he is a member of the Project(3) and the Task(2) is in the Project(3).
The Roles of the security service can't handle that. The ACL could handle it but I don't want to store the rights in my database because I know that they are going to change a lot during the life of the product.
Is there a known good practice for that kind of needs or should I write my own system?
Thanks.
"that they are going to change a lot during the life of the product" -> IMO, storing in database is the best, and ACLs are a good way to do that.
In your example above, ACLs would be great to manage rights between User and Projects, and rights on Tasks are depending on this Project Rights.
These rights would be accessible in your controllers and you views with respectively isGranted() and is_granted() if you implement your own aclVoter: http://symfony.com/doc/current/cookbook/security/voters.html
Is it possible to store user (and therefore use in e.g. asp.net) a staff hierarchy in active directory e.g. staff > manager relationships.
My active directory install is relatively flexible, so I could add additional information.
It's certainly possible to extend the AD schema to support what you want to do, but I would seriously consider why you want to do it, and how many changes you might make down the road (not to mention how unhappy your system administrator might be after these changes).
The presence of AD is not a prerequisite to using built-in Asp.net authentication methods (although it makes integrated authentication much easier). If this kind of data is application specific, I would recommend looking into maintaining the data in an application-specific database. In doing so, you could pull the current user's FQDN from the HttpContext.Current.User, and key on the Name property of the associated Identity. For example:
HttpContext.Current.User.Identity.Name
From that point, you simply create a UserProfile table with associated organizational structures (i.e. a column for ReportsTo that acts as a reference to another UserProfile.
Our requirement is something like this.
We are building a multi-tenant website in ASP.NET MVC, and each customer should be able to create their own users as per predefined user roles.
We are thinking about to create a schema for few tables which would be common for customers. So customer can login to system according to their schema logins and we need not to alter any queries to serve all of them.
We are referring http://msdn.microsoft.com/en-us/library/aa479086.aspx Shared Database, Separate Schemas.
Can someone suggest on following
1. After creating schema how to authorize user against a particular schema
2. Is this possible that without any changes in queries db can serve multi-tenants
Thanks in advance
Anil
After much research, I can say that, although it takes more development up front and more checks along the way, shared database and shared schema is the way to go. It puts a little bit of limits on how easily you can cater to a client's specific needs, but from my point of view SAAS isn't about catering to a single client's weird needs. It's about catering to the majority of clients. Not that it's a SAAS but take iPhone as an example. It was built to cater to the masses. Rather than focusing on doing everything it's built to be one-size fits all just by its simplicity. This doesn't help your case when it comes to authoriztion but it'll save you dev hours in the long run.
If you are asking this in the context of SQL Server authentication/authorization mechanism, i can asnwer this question with saying that every user has a default schema which helps query engine to find out required object in the database.
SQL Query Engine will look at the user's default schema first to find the required object (table). If it founds the object in user's schema then use it, otherwise goes to system default schema (dbo) to find it.
Check this article's How to Refer to Objects section to find out how it works. The article also has some information about security concepts related to schemas.
My company is building an ASP.NET HR application and we have decided to create one database per client. This ensures that clients cannot accidentally view another client's data, while also allowing for easy scalability (among other benefits, already discussed here).
My question is - what is the best way to handle security and data access in such a scenario? My intent is to use a common login/account database that will direct the user to the correct server/database. This common database would also contain the application features that each user/role has access.
I was not planning to put any user information in each individual client database, but others on my team feel that the lack of security on each database is a huge hole (but they cannot articulate how duplicating the common access logic would be useful).
Am I missing something? Should we add an extra layer of security/authentication at the client database level?
Update:
One of the reasons my team felt dual user management was necessary is due to access control. All users have a default role (e.g. Admin, Minimal Access, Power User, etc.), but client admins will be able to refine permissions for users with access to their database. To me it still seems feasible for this to be in a central database, but my team doesn't agree. Thoughts?
We have a SaaS solution that uses the one DB per client model. We have a common "Security" database too. However, we store all user information in the individual client databases.
When the user logs into the system they tell us three pieces of information, username, password and client-id. The client-id is used to lookup their home database in the "security" database, and then the code connects to their home database to check their username/password. This way a client is totally self-contained within their database. Of course you need some piece of information beyond username to determine their home database. Could be our client-id approach, or could be the domain-name requested if you're using the sub-domain per client approach.
The advantage here is that you can move "client" databases around w/out having to keep them synced up with the security database. Plus you don't need to deal w/cross-db joins when you're trying to lookup user information.
Update: In response to your update... One of the advantages to each customer having their own DB is also the ability to restore a customer if they really need it. If you've split the customer's data into two databases how do you restore it? Also, again, you'll need to worry about cross-db data access if the users are defined in a DB other than the home DB.
I've always been of the opinion that security should be enforced at the application level, not the database level. With that said, I see no problem with your intended approach. Managing accounts and roles through a central database makes the application more maintainable in the long run.
You may want to look into using the ASP.NET membership provider for handling the authentication plumbing. That would work with your stated approach and you can still keep all of the authentication data in a separate database. However, I agree with Chris that keeping one DB will utlimately be more maintainable.