Is "view as someone else" recommended from the software design perspective? - permissions

Some time ago, Facebook introduced a feature that helps set up the permissions on ones profile: view as someone else. It allows the author of a dynamic page to see which user groups (or specific users) can see which information in the page, and thereby debug the permissions. A similar feature exists in LinkedIn
The modern applications, especially B2B, may have much more complex permission settings. Therefore such tool is much more useful. However as far as I know, this function is not very wide spread. I wonder what the disadvantages may be, or if there is any RFC and best practice article I can read before considering it for my own project.

Sure, this is called "RunAs", "impersonation", "sudo"...
It is built-in to Spring Security: http://docs.spring.io/spring-security/site/docs/4.0.4.RELEASE/reference/htmlsingle/#runasmanager
It's also built in to most database servers:
https://msdn.microsoft.com/en-us/library/ms181362.aspx
Adding any complexity to a secure application makes it a little more likely to be vulnerable.

Related

DB structure/architecture with a auth SASS

My team and I are considering using an authentication SASS.
I am definitely sure that the SASS solution will eventually be more secure than the hand made one (even using proper libs) and in our case we can afford the money.
But the thing that makes me hesitate the most is how this service will discuss with the rest of my app. Will it actually simplify our code or make it a more complicated knot bag in the end?
I understand that user list with credentials, and eventual attributes are stored there.
But then, what should I store in my app's (SQL) DB?
Say I have users that belong to companies and other assets on a 1 - n relationship.
I like to write things like:
if current_user.company.assets includes current_user.assets do
// logic here
end
Should I:
only store userIds in these tables?
=> But then, I can't user relationships between user attributes and rest of the DB attributes
store some kind of cached data in a so-called sessions table so I can use it as a disposable table of active users?
=> It feels less secure and implies duplicated content which kind of sucks.
making the user object virtual loaded with the auth SASS data and use it there.
=> Slightly better, but I can't make queries over users, even company.users is not available
other proposition?
I'm highly confused on the profits of externalizing what's usually the core object of an app. Am I thinking too monolithically? :-D
Can anyone make suggestions? Even better would be feedback from devs who implemented it.
I found articles on the web, they talk about security and ease of implementation, but don't tackle this question properly.
Cheers, I hope the question doesn't get closed as I'm very curious about the answer.
I'm highly confused on the profits of externalizing what's usually the core object of an app. Am I thinking too monolithically? :-D
Yes, you are thinking too monolithically by assuming that you have to write and control all the code. You have asked a question about essentially outsourcing Authentication to an existing SASS based solution, when you could just as easily write your own. This is a common mistaken assumption that many developers make, especially in the area of Security for applications.
Authentication is a core requirement for many solutions, but it is very rarely a core aspect or feature of the solution.
By writing your own solution to what is a generally standard concept (Authentication) you have to write, test and maintain your logic, including keeping up to date with latest security trends over the lifetime of the product. In terms of direct Profit/Cost:
Costs you a lot of time and effort to get it right
Your own solution will add a layer of technical debt, future developers (internal or external) will need to familiarise themselves with your implementation before they can even start maintenance or improvement work
You are directly assuming all the risks and responsibilities to maintain the security of the solution and its data.
Depending on the type of data and jurisdiction of your application you may be asked down the track to implement multi-factor authentication or to force all users to re-register to adopt stronger security protocols, this can be a lot of effort for your own solution, or a simple tick of a box in the configuration of your Authentication provider.
Business / Data Schema
You need to be careful to separate the two concepts of Authentication and a User in the business domain. Regardless of where or what methodology you use to Authenticate your users, from a data integrity point of view it is important that there is a User concept in the database to associate related data for each user.
So there is no way around it, your business domain logic requires a table to represent a User in this business domain.
This User table should have an arbitrary Primary Key that is specific to the Application domain, and in that table store the token that that is used to map that business user to the Authentication process. Then throughout your model, you can create FK references back to the user table.
In this way it may be possible for you to map users to multiple different providers, or to easily change the provider with minimal or zero impact on the rest of the business domain model.
What is important from a business process point of view is that the application can resolve the correct business User from the token or claims provided in the response from the authentication provider.
Authentication
If SSO (Single Sign On) is appealing to you then the choice of which Authentication provider to use can become an issue depending on the nature of your solution and the type of users who will be Authenticating. If the solution is tenanted to other businesses and offers B2B, or B2C focused activities then an Enterprise authentication solution like Azure AD, or Google Cloud Identity might make sense. You would register your product in the client's authentication domain so that they can manage their users and access levels.
If the solution is more public focussed then you might consider other social media Authentication providers as a means of simplifying Authentication for users rather than forcing them to use your own bespoke Authentication process that they will invariably forget their password too...
You haven't mentioned what language or runtime you are considering, however if you do choose to write your own Authentication service, as a bare minimum you should consider implementing an OAuth 2.0 implementation to ensure that your solution adheres to standard practises and is compatible with other providers chould you choose to use them later.
In a .NET based environment I would suggest Identity Server 4 as a base level of security, there are a lot of resources on implementation, other frameworks should have similar projects or providers that you can host yourself. The point is that by using a standard implementation of your own Authentication Service, rather than writing your own one that is integrated into your software you are not re-inventing anything, there is a lot of commercial and community support available to help you minimise the effort and cost to get things up and running.
Conclusion
Ultimately, if you are concerned with Profit, and lets face it most of us are, then the idea that you would re-create the wheel, just because you can adds a direct implementation and long term maintenance Cost and so will directly reduce Profitability, especially when the effort to implement existing Authentication providers into your solution is really low.
Even if you choose today to implement your own Authentication Service, it would be wise to implement it in such a way that you could easily offload that workload to an external provider, it is the natural evolution of security for small to mid sized applications when users start to demand more stringent security requirements or additional features than it is cost effective to provide in your native runtime.
Once security is implemented in your application the rest of the business process generally evolves and we neglect to come back and review authentication until after a breach, if we or the client ever detect such an event, for this reason it is important that we get security as right as we can from the very start of a solution.
Whilst not directly related, this discussion reminds me of my faviourite quote from Eric Lippert in a comment on an SO blog
Eric Lippert on What senior developers can learn from beginners
...The notion that programming can be principled — that we proceed by understanding the abstractions afforded by the language, and then match those abstractions to a model of the business domain of the program — is apparently never taught to a great many programmers. Rather, many programmers proceed as though they’re exploring an undiscovered country, and going down paths more or less at random and hoping they end up somewhere good, no matter how twisted the path is that gets them there...
One of the reasons that we use external Authentication Providers is that the plethroa of developers who have come before us have already learnt the hard lessons on what to do, or not to do and have evolved a set of standards and protocols to provide best practice guidelines on how to protect our users and their data when they are using our software. Many of these external providers represent best practice implementations and they maintain them for us as the standards continue to evolve, so that we don't have to.

Benefits of using Auth0 with a Parse Server/React Native application?

I'm wondering about additional complexities involved in integrating with Auth0 vs plenty of available code for password complexity rules, UI etc. including using snowflake starter app, for authentication/user creation with open source parse server.
I am sure plenty of people have thought about this and was wondering what the consensus is? Requirement to keep profile/email in sync, relying on 3rd party, inability to customize view and I am sure many other issues.
At first I thought this is great, I would not need to worry about a lot of things, yet there are a lot of other things to worry about and not being able to customize.
What are the most convincing "PRO" answers?
Disclosure: I'm an Auth0 engineer.
TL;DR: I can talk about the pros and cons, but the definitive answer needs to be provided by you.
A bit about Auth0
Auth0 supports the authentication protocols in most widespread use (OAuth2/OIDC, SAML and WS-Federation) so integration into custom software that speaks or can be made to speak by available libraries is relatively easy and friction free. Sidenote, Parse Server does seem to support integration with OAuth compliant identity providers.
It can be used as a standalone identity provider where your users register and authenticate with username/password credentials specific to your application, but it can also integrate with a lot of downstream identity providers like for example Google, GitHub and Twitter. This makes it really easy to enable different methods of authenticating users just by configuration instead of having to directly talk to each individual provider and have to deal with their implementation discrepancies.
Finally, it provides enough extensibility points for you to still have significant degree of control on the authentication experience, for example:
Rules (JS code) allow you to customize the authentication process
Customization of Auth0 provided authentication user interface allows you to still have your own branding
Customization of Lock allows you to have a custom authentication experience integrated in your own app really quick and with very little effort
Of course, no matter how many extension points there's always some stuff that you will not be able to control. This can be seen as bad, but sometimes it's actually a good thing. Depends on the perspective and your specific requirements.
Comparison - Roll your own (RYO) vs Third-party service
On one side you'll have:
cost of acquisition of the service
cost of integration of the service with your product
On the other side you'll have:
cost of implementing the features you need
cost of ownership of those features
cost of integration of the new features in your product
In both cases you'll need some integration work in order to make all the parts fit no matter who created the parts. You could argue that if you are the author of everything it will be easier to fit a square peg in a round hole so lets say RYO wins by a small margin on that point.
It then all comes to comparing cost of acquisition versus the cost of implementation and ownership. I can't answer that one, but the cost of acquisition is generally easy to calculate while the cost of implementing software is very hard to predict; on top of that owning a custom authentication solution also has a heavy toll... you know what they say, no one ever got fired by buying IBM. I won't go that further, but it's safe to say it's easier to find yourself in a pickle if you roll your own security. :)
Conclusions
Go through the Auth0 trial, play with it and see what it has to offer and how that matches your requirements.
If you find something you're not able to accomplish leave a question here tagged auth0 or on Auth0 Forums.

What does "Opinionated API" mean?

I came across the term "Opinionated API" when reading about the ssl.create_default_context() function introduced by Python 3.4, what does it mean? What's the style of such API? Why do we call it an "opinionated one"?
Thanks a lot.
It means that the creator of the API makes some choices for you that are in her opinion the best.
For example, a web application framework could choose to work best with (or even bundle or work exclusively with) a selection of lower-level libraries (for stuff like logging, database access, session management) instead of letting you choose (and then have to configure) your own.
In the case of ssl.create_default_context some security experts have thought about reasonably secure defaults to configure SSL connections. In particular, it limits the available algorithms to those that are still considered secure, at the expense of complete compatibility with legacy systems, a trade-off that is beneficial in their (and my) opinion.
Essentially they are saying "we have a lot of experience in this domain, and we really think you should do things in the following way".
I suppose this is a response to "enterprise" API that claim to work with every implementation of as many standard interfaces as possible (at the expense of complexity in configuration and combination, requiring costly consultants to set up everything).
Or a natural extension of "Convention over Configuration".
Things should work very well out-of-the-box, so that you only have to twiddle around with expert settings in special cases (and by then you should know what you are doing), as opposed to even a beginner having to make informed decisions about every aspect of the application (which can end in disaster).

Should I default the environment for someone using my library?

I have been having this debate with a friend where i have a library (its python but I didn't include that as a tag as the question is applicable to any language) that has a few dependencies. The debate is whether to provide a default environment in the initialization or force the user of the code to explicitly set one.
My opinion is to force the user as its explicit and will avoid confusion and make it clear what they are pointing to.
My friend this is safer and more convenient to default to an environment and let the user override if he wants to.
Thoughts ? Are there any good references or examples / patterns in popular libraries that support either of our arguments? also, any popular blogs or articles that discuss this API design point?
I don't have any references, but here are my thoughts as a potential user of said library.
I think it's good to have a default configuration available to allow developers to quickly evaluate the library. I don't want to have to go through a bunch of configuration just to see if the library will do what I need. Once I'm happy that the library will do what i need it to do, then I'm happy to configure it the way I want.
A good example is Microsoft's ASP.Net MVC framework. When you create a new MVC project it hooks in a default authentication and membership provider, which allows the developer to very quickly get a functioning application up and running. It is also easy to configure different providers to be used if the default one's don't meet the requirements of the application in question.
As a slightly different example, Atlassian Confluence is wiki software which supports many different back-end databases. Atlassian could have chosen to have no default DB configuration, but instead Confluence ships with a default, simple, file-based database to allow users to evaluate the software. For production installations you can then hook up to Oracle, SQL Server, mySQL or whatever else you like.
There may be instances where a default configuratino for a library doesn't really make sense, but I think that would be a special case, rather than a general rule.
It depends. If you can provide sensible defaults, you might want to do that: it will make life easer on the occasional user of the library as they can set only the relevant settings, as opposed to the whole environment (with possibly settings the implications of which they don't fully understand (yet)). You are correct, that in situations it is possible this leads to frustration and confusion as the defaulted settings might cause unexpected behavior (unexpected by the (inexperienced) user) -- you have to weigh the reduced frustration of convenience against the price of not-understood defaults to make the choice for each of these possible-to-default settings, which choice might affect the choice for other, related settings as well
On the other hand, if there is no sensible default (e.g. DB credentials, remote address), you should require the user to provide those settings.
The key in both cases is to provide enough information in the documentation of the library and in the error messages (either for missing settings or conflicting ones) that the user can figure out what those settings actually mean/control without having to read through the source code of the library. This part is hard because 1) it is usally tedious from the point of view of the library developer (so it is often skimped) and 2) the documentation has to be written from the mindset of a newbie to the library, which is often different from the library developer's mindset -- the latter knows the implicit connections/implications, the former has to be told about those in an understandable way.
Although not exactly identical in terms of problem domain, this strikes me as the Convention over Configuration argument.
There has been quite a lot momentum behind CoC in recent years, and in my mind, it makes a whole lot of sense. As long as flexibility is not lost, you have everything to gain. Lower friction development is what we are all after, and if I've got to configure every aspect of your API in order to get it working, I'm less inclined to use it over another API of equal functionality.
I happen to like Hanselman's podcasts, so if you want a little light listening, check out this podcast.
I think your question needs some clarification. For starters, I don't think a library should have any runtime configuration. In terms of dependencies, library dependencies should be handled in a manner appropriate to the environment they are being written for. In python, those dependencies should be in the setup.py file (under requirements), and ultimately that file should meet the requirements of whatever service you plan on making it available on (i.e. pypi for python).
For applications, it is completely okay to require runtime configuration, but you should try to have sensible defaults. If your application depends on libraries, that dependency should be handled in the same way a library dependency would be handled, even though that information may be redundant in the context of an installer (if needed). For the most part first-run scripts and their ilk should be apart of the installer/rpm.
For Web Frameworks, it is typical that your app would carry configuration with it, and likely that it would need to be installed in a different way than traditional applications. Here, about the only thing you can do is try to follow the conventions of whatever framework you are writing in.

How can developers let business users define application logic?

I'm working on a new application at work, and a manager is really pushing the concept of a business rules management system (BRMS) and a workflow management system, and I'm trying to figure out the best way of integrating these types of tools.
With regard to these types of systems, I don't know what I don't know, so I'm trying to get other perspectives and information.
The thing the manager is looking for is the ability for business users to change business rules or process flows without the need for developer time (or with minimal developer time).
A BRMS is easier for me to understand when I think about how it would fit into code. It's pretty straightforward, and I can see how the logic could reside completely outside of an application. Since I haven't done much with these types of systems, I would appreciate any info on good products that integrate with .NET, or info on experiences. (We're looking at InRule, Blaze Advisor and ILOG Rules)
What I'm less sure of is the workflow part.
Workflow Foundation makes sense to me, as it's a known, defined workflow that's integrated into application code, but the manager isn't looking for a foundation, he wants a tool that lets business users define and update workflows. Any type of system that allows end users to dynamically create workflows makes less sense to me.
I was asked to look at WorkflowGen as an example of a workflow engine. To me, it looks like it's completely self-contained unless a developer writes .NET code to interface with back-end systems.
I can understand a workflow system that allows users to define specific, limited actions, like "e-mail so and so" and "require so and so to approve," but I have no idea how a workflow system that's supposed to dynamically define application flow can be integrated in to an application, or even how the more simplistic system I just described can display and update back-end data.
I'm pushing for use cases so I can better understand what my manger is looking for in terms of moving these types of logic outside of application code, but in the meantime, I'd appreciate any info anyone has on these types of systems. As I said, I don't know what I don't know, and our business users seem to think our new application should support these types of tools. I want to make sure I'm limiting our functionality due to my lack of knowledge.
Thanks for any information or advice.
If you work in .NET: .NET Workflow Foundation. It's complex, true, but it's free and has everything your manager asks for. Business rules part will require some getting used to, the workflow will need some initial investment in building your own "environment" but, when you look at all this from above, WF.NET still gives more than what others has to offer. InRule is a cheap product that can't really do much, Blaze is way too complex, way too expensive and not really for "non-programmers"; ILOG is, too, not for "business users".