Is there any way to restrict post requests to my REST API only to requests coming from my own mobile app binary? This app will be distributed on Google Play and the Apple App Store so it should be implied that someone will have access to its binary and try to reverse engineer it.
I was thinking something involving the app signatures, since every published app must be signed somehow, but I can't figure out how to do it in a secure way. Maybe a combination of getting the app signature, plus time-based hashes, plus app-generated key pairs and the good old security though obscurity?
I'm looking for something as fail proof as possible. The reason why is because I need to deliver data to the app based on data gathered by the phone sensors, and if people can pose as my own app and send data to my api that wasn't processed by my own algorithms, it defeats its purpose.
I'm open to any effective solution, no matter how complicated. Tin foil hat solutions are greatly appreciated.
Any credentials that are stored in the app can be exposed by the user. In the case of Android, they can completely decompile your app and easily retrieve them.
If the connection to the server does not utilize SSL, they can be easily sniffed off the network.
Seriously, anybody who wants the credentials will get them, so don't worry about concealing them. In essence, you have a public API.
There are some pitfalls and it takes extra time to manage a public API.
Many public APIs still track by IP address and implement tarpits to simply slow down requests from any IP address that seems to be abusing the system. This way, legitimate users from the same IP address can still carry on, albeit slower.
You have to be willing to shut off an IP address or IP address range despite the fact that you may be blocking innocent and upstanding users at the same time as the abusers. If your application is free, it may give you more freedom since there is no expected level of service and no contract, but you may want to guard yourself with a legal agreement.
In general, if your service is popular enough that someone wants to attack it, that's usually a good sign, so don't worry about it too much early on, but do stay ahead of it. You don't want the reason for your app's failure to be because users got tired of waiting on a slow server.
Your other option is to have the users register, so you can block by credentials rather than IP address when you spot abuse.
Yes, It's public
This app will be distributed on Google Play and the Apple App Store so it should be implied that someone will have access to its binary and try to reverse engineer it.
From the moment its on the stores it's public, therefore anything sensitive on the app binary must be considered as potentially compromised.
The Difference Between WHO and WHAT is Accessing the API Server
Before I dive into your problem I would like to first clear a misconception about who and what is accessing an API server. I wrote a series of articles around API and Mobile security, and in the article Why Does Your Mobile App Need An Api Key? you can read in detail the difference between who and what is accessing your API server, but I will extract here the main takes from it:
The what is the thing making the request to the API server. Is it really a genuine instance of your mobile app, or is it a bot, an automated script or an attacker manually poking around your API server with a tool like Postman?
The who is the user of the mobile app that we can authenticate, authorize and identify in several ways, like using OpenID Connect or OAUTH2 flows.
Think about the who as the user your API server will be able to Authenticate and Authorize access to the data, and think about the what as the software making that request in behalf of the user.
So if you are not using user authentication in the app, then you are left with trying to attest what is doing the request.
Mobile Apps should be as much dumb as possible
The reason why is because I need to deliver data to the app based on data gathered by the phone sensors, and if people can pose as my own app and send data to my api that wasn't processed by my own algorithms, it defeats its purpose.
It sounds to me that you are saying that you have algorithms running on the phone to process data from the device sensors and then send them to the API server. If so then you should reconsider this approach and instead just collect the sensor values and send them to the API server and have it running the algorithm.
As I said anything inside your app binary is public, because as yourself said, it can be reverse engineered:
should be implied that someone will have access to its binary and try to reverse engineer it.
Keeping the algorithms in the backend will allow you to not reveal your business logic, and at same time you may reject requests with sensor readings that do not make sense(if is possible to do). This also brings you the benefit of not having to release a new version of the app each time you tweak the algorithm or fix a bug in it.
Runtime attacks
I was thinking something involving the app signatures, since every published app must be signed somehow, but I can't figure out how to do it in a secure way.
Anything you do at runtime to protect the request you are about to send to your API can be reverse engineered with tools like Frida:
Inject your own scripts into black box processes. Hook any function, spy on crypto APIs or trace private application code, no source code needed. Edit, hit save, and instantly see the results. All without compilation steps or program restarts.
Your Suggested Solutions
Security is all about layers of defense, thus you should add as many as you can afford and required by law(e.g GDPR in Europe), therefore any of your purposed solutions are one more layer the attacker needs to bypass, and depending on is skill-set and time is willing to spent on your mobile app it may prevent them to go any further, but in the end all of them can be bypassed.
Maybe a combination of getting the app signature, plus time-based hashes, plus app-generated key pairs and the good old security though obscurity?
Even when you use key pairs stored in the hardware trusted execution environment, all an attacker needs to do is to use an instrumentation framework to hook in the function of your code that uses the keys in order to extract or manipulate the parameters and return values of the function.
Android Hardware-backed Keystore
The availability of a trusted execution environment in a system on a chip (SoC) offers an opportunity for Android devices to provide hardware-backed, strong security services to the Android OS, to platform services, and even to third-party apps.
While it can be defeated I still recommend you to use it, because not all hackers have the skill set or are willing to spend the time on it, and I would recommend you to read this series of articles about Mobile API Security Techniques to learn about some complementary/similar techniques to the ones you described. This articles will teach you how API Keys, User Access Tokens, HMAC and TLS Pinning can be used to protect the API and how they can be bypassed.
Possible Better Solutions
Nowadays I see developers using Android SafetyNet to attest what is doing the request to the API server, but they fail to understand it's not intended to attest that the mobile app is what is doing the request, instead it's intended to attest the integrity of the device, and I go in more detail on my answer to the question Android equivalent of ios devicecheck. So should I use it? Yes you should, because it is one more layer of defense, that in this case tells you that your mobile app is not installed in a rooted device, unless SafetyNet has been bypassed.
Is there any way to restrict post requests to my REST API only to requests coming from my own mobile app binary?
You can allow the API server to have an high degree of confidence that is indeed accepting requests only from your genuine app binary by implementing the Mobile App Attestation concept, and I describe it in more detail on this answer I gave to the question How to secure an API REST for mobile app?, specially the sections Securing the API Server and A Possible Better Solution.
Do you want to go the Extra Mile?
In any response to a security question I always like to reference the excellent work from the OWASP foundation.
For APIS
OWASP API Security Top 10
The OWASP API Security Project seeks to provide value to software developers and security assessors by underscoring the potential risks in insecure APIs, and illustrating how these risks may be mitigated. In order to facilitate this goal, the OWASP API Security Project will create and maintain a Top 10 API Security Risks document, as well as a documentation portal for best practices when creating or assessing APIs.
For Mobile Apps
OWASP Mobile Security Project - Top 10 risks
The OWASP Mobile Security Project is a centralized resource intended to give developers and security teams the resources they need to build and maintain secure mobile applications. Through the project, our goal is to classify mobile security risks and provide developmental controls to reduce their impact or likelihood of exploitation.
OWASP - Mobile Security Testing Guide:
The Mobile Security Testing Guide (MSTG) is a comprehensive manual for mobile app security development, testing and reverse engineering.
No. You're publishing a service with a public interface and your app will presumably only communicate via this REST API. Anything that your app can send, anyone else can send also. This means that the only way to secure access would be to authenticate in some way, i.e. keep a secret. However, you are also publishing your apps. This means that any secret in your app is essentially being given out also. You can't have it both ways; you can't expect to both give out your secret and keep it secret.
Though this is an old post, I thought I should share the updates from Google in this regard.
You can actually ensure that your Android application is calling the API using the SafetyNet mobile attestation APIs. This adds a little overhead on the network calls and prevents your application from running in a rooted device.
I found nothing similar like SafetyNet for iOS. Hence in my case, I checked the device configuration first in my login API and took different measures for Android and iOS. In case of iOS, I decided to keep a shared secret key between the server and the application. As the iOS applications are a little bit difficult to reversed engineered, I think this extra key checking adds some protection.
Of course, in both cases, you need to communicate over HTTPS.
As the other answers and comments imply, you cant truly restrict API access to only your app but you can take different measures to reduce the attempts. I believe the best solution is to make requests to your API (from native code of course) with a custom header like "App-Version-Key" (this key will be decided at compile time) and make your server check for this key to decide if it should accept or reject. Also when using this method you SHOULD use HTTPS/SSL as this will reduce the risk of people seeing your key by viewing the request on the network.
Regarding Cordova/Phonegap apps, I will be creating a plugin to do the above mentioned method. I will update this comment when its complete.
there is nothing much you can do. cause when you let some one in they can call your APIs. the most you can do is as below:
since you want only and only your application (with a specific package name and signature) calls your APIs, you can get the signature key of your apk pragmatically and send is to sever in every API call and if thats ok you response to the request. (or you can have a token API that your app calls it every beginning of the app and then use that token for other APIs - though token must be invalidated after some hours of not working with)
then you need to proguard your code so no one sees what you are sending and how you encrypt them. if you do a good encrypt decompiling will be so hard to do.
even signature of apk can be mocked in some hard ways but its the best you can do.
Someone have looked at Firebase App Check ?
https://firebase.google.com/docs/app-check
Is there any way to restrict post requests to my REST API only to requests coming from my own mobile app binary?
I'm not sure if there is an absolute solution.
But, you can reduce unwanted requests.
Use an App Check:
The "Firebase App Check" can be used cross-platform (https://firebase.google.com/docs/app-check) - credit to #Xande-Rasta-Moura
iOS: https://developer.apple.com/documentation/devicecheck
Android: https://android-developers.googleblog.com/2013/01/verifying-back-end-calls-from-android.html
Use BasicAuth (for API requests)
Allow a user-agent header for mobile devices only (for API requests)
Use a robots.txt file to reduce bots
User-agent: *
Disallow: /
Using Laravel for PHP and DBMS. How do I make an app? (for social networking).
I have googled most of the things but I am really an Amateur and need help.
There are many kinds of apps, so before you start to work on your app, you need to carefully determine what exactly you need. You could write desktop apps for various operating systems, or native mobile apps, or hybrids, or a web application... You name it. Anyway, Laravel is the server-side and it should be as agnostic to the apps as possible. You need to create an API and handle the following things:
CRUD for the database
session (log in, log out, register, password change, user settings)
logical API functions
file transfer protocol usage
push notification (if needed)
As per your requirements, you will need to implement the server-side API in Laravel, which is a PHP-based framework and use an RDBMS, which could be MySQL, SQL Server, Oracle, or a NoSQL database, for instance MongoDB.
Before you implement any apps, you should have a proof-of-concept for the API. You should not invest too much time working out the details of the API, as when you are going to work on a real app, you will notice things to be changed anyway. The API should be accompanied by a playground for testing, maybe a very small app without design where you could send requests to the API. Or you can implement a WebSocket API to have a single, duplex connection. It is up to you.
As about how to write an API, there are many tutorials.
Is there any way that I can integrate the UserCake user management system with MediaWiki? I want to link the accounts in each system so users can log into both with the same username and password.
There is no existing system to do this. You can create an extension for MediaWiki to do this without too much trouble. Basing it off an existing extension is probably a good starting point. By looking at AuthJoomla, AuthBugzilla and AuthSymfony you should get a good idea of how MediaWiki's authentication extension API operates. It's really just a matter of creating the class, getting it to call the relevant UC functions and then loading it as an extension into MW.
Having said that, UserCake seems unmaintained. It may be worth taking this opportunity to migrate your users to another authentication system. If you are using credentials between several applications you might want to look at something like LDAP.
I know that this is a really old question, but UserSpice is the fully PDO/OOP spiritual successor to UserCake and would probably be better equipped to handle this. It would take some modification, but it could be done.
May I recommend that you use other ways to secure you applications. Take a look at Windows Azure ACS that gives you security federation to Facebook, Google, Yahoo and more.
This allows you to focus on your application and not security protocols.
Azure ACS supports many different of protocols and works great with PHP as well as .Net based applications.
I did a quick search and found the http://www.mediawiki.org/wiki/Extension:OpenID that can use Azure ACS. (Access Control Services)
There are other alternatives to ACS such as Ping Identity and OpenSSO; But ACS is a cheap alternative to Ping.
Q: How would you create a SSO? What would you do about authentication (separate app or same as sso) and user store?
Background info:
We have 40+ php apps, java apps and
Ruby apps.
Currently, we have a custom
SSO+authentication solution. It's an
app written in php that is now used as
SSO, while supporting
email/username/phone-number + password
as authentication. It works, but was
built for a few apps only, not
originally meant to be the SSO -
solution. It doesn't have a usable view, every app create their own login/register forms and use the API. They share context and we'd like a more universal design.
Now we know want to support Oauth and
openid solutions, as facebook connect,
google and more, (or do we really?), in addition to
existing authentications. We can
expand existing php-solution, but we
are considering alternatives.
If you were to do all this in Ruby, what would you do?
Some additional info:
All users exist in SSO, today.
The company does aquire other companies/systems at times, having their own users. Would you migrate or create some kind of mapper?
Customers in a Microsoft CRM, but I consider this unrelated. Or do I?
I've shallowly looked at RubyCAS and ClassyCAS, and don't know if they are suitable. Is CAS the way to go?
Would you keep going with php? What would you use?
As you see, I have a lot of questions. What would you suggest?
I a previous job we used Jasig CAS for SSO (several apps in Java and Python). After getting over some quirks in the configuration and my dislike of all things Java, it actually worked pretty well. At the time I found the wiki to be a valuable resource, but things might have changed in the last year.
Authentication was handled via a separate app (custom) using an OpenLDAP directory that was preinitialized with a script that got user info out of an AD server.
Regarding the actual server you might actually want to use the Jasig one, IIRC it's the reference implementation and is easy to customize via a Maven overlay.
Ruby-cas FTW.
We're planning a new project which will feature an API available to customers to interact with our app from their own web sites and systems. However never having built anything close to an full-fledged API in the past, I am not aware of any standards or recommendations that are available and could be used to make the API more easily adapted by our customers.
We will build the API using PHP and some parts of the API will need authentication while others don't. As of today, I have read a little about Oauth, SOAP & REST, but I have no idea on what is good practiec.
What technology/standard is recommended to base an API for 2011+ upon?
There are a number of options, but I would suggest that you may find publishing a SOAP API from PHP quite tricky to maintain.
The reason for this is that there is no inherent WSDL generation within PHP, so you'll either have to roll your own (and modify it each time), or experiment with one of the 3rd party tools - none of which I have found particularly satisfactory in the past.
I would suggest that a more straightfoward method for implementing an API in PHP would be to go down the RESTful route.
I would check out the choices made by successful APIs that are available through sites like Mashery or Programmable Web. By focusing on the successful API patterns before choosing a technology you will have a better chance that the API will work and be successful.