I have written my own api and I want to upload it to the server but I want to secure it so noone can access it except from my app, I have tried slim-basic-auth library but it didn't work, I don not know why...
any help with that please ?
$app->add(new Tuupola\Middleware\HttpBasicAuthentication([
"secure"=>false,
"users" => [
"userher##" => "passhere##" ]
]));
I think you will never be able to hide the api url being called by the app (an attacker with rooted android device can intercept traffic easily ), If your api response user specific data, you can add auth header in request and same verify this header at server. You can also use Cross-Origin Resource Sharing-CORS and SSL for extra layer of security.
YOUR QUESTIONS
In a glance you want to have a private API, lock your Android App to it, and solve your code issue in the API server. Let's address each one in the order I mentioned them.
PRIVATE APIs
How to protect my own api from hacking and make it private
Well I have a cruel truth to reveal to you, no such thing as a private API exists, unless you don't expose it to the Internet, aka only have it accessible inside a private network, via programs that themselves are not expose also to the internet. By other words your API can only be private if its is air gaped from the internet.
So no matter if an API doesn't have public accessible documentation or if is is protected by any kind of secret or authentication mechanisms, once is accessible from the Internet is not private any-more, and you even have tooling to help with discover them.
You can read more about it in this article section, and I extract to here some bits:
Now just because the documentation for your API is not public or doesn’t even exist, it is still discoverable by anyone having access to the applications that query your API.
Interested parties just need to set up a proxy between your application and the API to watch for all requests being made and their responses in order to build a profile of your API and understand how it works.
A proxy tool:
MiTM Proxy
An interactive TLS-capable intercepting HTTP proxy for penetration testers and software developers.
So the lesson here is that from the moment you release a mobile app that uses your API, you can consider it to belong now to the public domain, because anyone can reverse engineer it and discover how your "private" API works, and use that to build automated attacks against it.
HOW TO LOCK AN API TO AN ANDROID APP
I have written my own api and I want to upload it to the server but I want to secure it so noone can access it except from my app
Well you bought yourself a very hard task to accomplish, that some may say that its impossible to do, but once you dig deep enough in the subject, you will be able to understand that you still have some paths to explore.
First you will need to understand the difference between WHO and WHAT is accessing your API server, followed by learning some of the most common techniques used to secure an API server, and finally you will learn that the Mobile App Attestation may be what your are looking for.
The Difference Between WHO and WHAT is Accessing the 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 WAHT is accessing your API server, but I will extract here the main take aways 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.
So think about the WHO as the user that your API server will be able to Authenticate and Authorize to access the data, and think about the WHAT as the software making that request in behalf of the user.
API Security Defenses
The Basic Defenses
Now that you understand the difference between WHO vs WHAT is accessing your API server you may want to go an read my article about the basic techniques to secure an API:
In this article we will explore the most common techniques used to protect an API, including how important it is to use HTTPS to protect the communication channel between mobile app and API, how API keys are used to identify the mobile app on each API request, how user agents, captchas and IP addresses are used for bot mitigation, and finally how user authentication is important for the mobile security and api security. We will discuss each of these techniques and discuss how they impact the business risk profile, i.e. how easy they are get around.
More Advanced Defenses
You can start by read this series of articles on Mobile API Security Techniques to understand how API keys, HMAC, OAUTH and certificate pinning can be used to enhance the security and at same time how they can be abused/defeated.
Afterwards and depending on your budget and resources you may employ an array of different approaches and techniques to defend your API server, and I will start to enumerate some of the most usual ones.
You can start with reCaptcha V3, followed by Web Application Firewall(WAF) and finally if you can afford it a User Behavior Analytics(UBA) solution.
Google reCAPTCHA V3:
reCAPTCHA is a free service that protects your website from spam and abuse. reCAPTCHA uses an advanced risk analysis engine and adaptive challenges to keep automated software from engaging in abusive activities on your site. It does this while letting your valid users pass through with ease.
...helps you detect abusive traffic on your website without any user friction. It returns a score based on the interactions with your website and provides you more flexibility to take appropriate actions.
WAF - Web Application Firewall:
A web application firewall (or WAF) filters, monitors, and blocks HTTP traffic to and from a web application. A WAF is differentiated from a regular firewall in that a WAF is able to filter the content of specific web applications while regular firewalls serve as a safety gate between servers. By inspecting HTTP traffic, it can prevent attacks stemming from web application security flaws, such as SQL injection, cross-site scripting (XSS), file inclusion, and security misconfigurations.
UBA - User Behavior Analytics:
User behavior analytics (UBA) as defined by Gartner is a cybersecurity process about detection of insider threats, targeted attacks, and financial fraud. UBA solutions look at patterns of human behavior, and then apply algorithms and statistical analysis to detect meaningful anomalies from those patterns—anomalies that indicate potential threats. Instead of tracking devices or security events, UBA tracks a system's users. Big data platforms like Apache Hadoop are increasing UBA functionality by allowing them to analyze petabytes worth of data to detect insider threats and advanced persistent threats.
All this solutions work based on a negative identification model, by other words they try their best to differentiate the bad from the good by identifying what is bad, not what is good, thus they are prone to false positives, despite of the advanced technology used by some of them, like machine learning and artificial intelligence.
So you may find yourself more often than not in having to relax how you block the access to the API server in order to not affect the good users. This also means that this solutions require constant monitoring to validate that the false positives are not blocking your legit users and that at same time they are properly keeping at bay the unauthorized ones.
Regarding APIs serving mobile apps a positive identification model can be used by implementing a Mobile App Attestation solution that attests the integrity of your mobile app and device its running on before any request is made to the API server.
Mobile App attestation
Finally if you have the resources you can go even further to defend your API server and Mobile App, by building your own Mobile APP Attestation, and you can read in this article section about the overall concept of it, from where I extracted this:
The role of a Mobile App Attestation service is to authenticate what is sending the requests, thus only responding to requests coming from genuine mobile app instances and rejecting all other requests from unauthorized sources.
In order to know what is sending the requests to the API server, a Mobile App Attestation service, at run-time, will identify with high confidence that your mobile app is present, has not been tampered/repackaged, is not running in a rooted device, has not been hooked into by an instrumentation framework(Frida, xPosed, Cydia, etc.), and is not the object of a Man in the Middle Attack (MitM). This is achieved by running an SDK in the background that will communicate with a service running in the cloud to attest the integrity of the mobile app and device it is running on.
On a successful attestation of the mobile app integrity, a short time lived JWT token is issued and signed with a secret that only the API server and the Mobile App Attestation service in the cloud know. In the case that attestation fails the JWT token is signed with an incorrect secret. Since the secret used by the Mobile App Attestation service is not known by the mobile app, it is not possible to reverse engineer it at run-time even when the app has been tampered with, is running in a rooted device or communicating over a connection that is the target of a MitM attack.
The mobile app must send the JWT token in the header of every API request. This allows the API server to only serve requests when it can verify that the JWT token was signed with the shared secret and that it has not expired. All other requests will be refused. In other words a valid JWT token tells the API server that what is making the request is the genuine mobile app uploaded to the Google or Apple store, while an invalid or missing JWT token means that what is making the request is not authorized to do so, because it may be a bot, a repackaged app or an attacker making a MitM attack.
A great benefit of using a Mobile App Attestation service is its proactive and positive authentication model, which does not create false positives, and thus does not block legitimate users while it keeps the bad guys at bay.
So a Mobile App Attestation will allow your API server to identify, with a very high degree of confidence, that the request is coming from WHAT you expect, the original and unmodified APK you have uploaded to the Google Play store.
THE API SERVER CODE ISSUE
I have tried slim-basic-auth library but it didn't work, I don not know why
I am not familiar at all with the Tuupola project, but from a look into the README.md for the Slim API Skeleton, specially the section for how to get a token and then how to use it. The related code that generates the token can be found at routes/token.php, and to use the token to protect an API route you can find an example at routes/todos.php. This is all configured in the config file config/middleware.php. But I have to say that I am not impressed, security wise, with their posture, and this is because they encourage the exposure of server sensitive data via API endpoints, as we can see at routes/token.php, thus I strongly advise you to immediately delete all this endpoints if they are present in your project.
SUMMARY
In my opinion the best solution is defense in depth, by applying as many layers as you can, so that you increase the time, effort and skill-set necessary to by pass all your security layers, thus keeping at bay the script kids and occasionally hackers from abusing your API server and Mobile App.
So you should employ has much techniques as possible in both sides of the equation, mobile app and API, like the ones you have learned when reading the articles I have linked: HTTPS, API keys, User Agents, Captchas, Rate Limiting, OAuth, HMAC, Certificate Pinning, Code Obfuscation, JNI/NDK to hide secretes, WAF, UBA, etc.
In the end, the solution to use in order to protect your API server and Mobile App must be chosen in accordance with the value of what you are trying to protect and the legal requirements for that type of data, like the GDPR regulations in Europe.
GOING THE EXTRA MILE
I would strongly recommend you, to also take a look into the 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.
The thing you need is to add a Variable from your client app passing to your server application. Like APP_KEY or CLIENT_ID, which allows your app connecting to the server. You can add encryption so that your server application can only decrypt it and identify the request coming from your client app.
If your app is a web application and hosted in another server, you can implement IP whitelisting in your server.
But if your app is Mobile, you need to pass like a secret_key from mobile to your server.
I have a WPF client that uses a JWT to access an ASP.NET Core Web API. I already having the client app running quietly in the 'System Tray'[1]. I would like to have the app start on Windows startup and continue running quietly there until the user needs it, but that would require the user to login again on each startup, making 'quietly' meaningless.
To prevent this, I will need a remember me option on the login dialogue, and when checked, I will have to safely store the JWT in use until the next startup.
How should I go about this? I have seen recommendations on using the registry or Isolated Storage for persisting runtime data over just storing it out on the hard drive somewhere. Then I would have to encrypt the JWT to keep it secure, but then a very similar question arises on how to store the encryption key.
How can I securely store these two values, most preferably in separate places?
[1] Or whatever it is called these days.
I've created a website within the company that utilizes our active directory server to authenticate. I am concerned about security surrounding setting up relying parties with "localhost" domains.
I've pretty much followed this guide on setup. You'll notice about halfway down the page, there is a step to set up the development environment, localhost:44336 as a relying party.
I am concerned that someone could easily get the location of our federation metadata document, and simply roll their own project utilizing the same port and get access to our active directory. Is this a valid concern, or am I worrying over nothing? What would be a better alternative to having to use localhost in this configuration?
Yes it's safe. The metadata document only describes information about endpoints and about the token that active directory is issuing. It doesn't inherently have anything sensitive about it.
The actual authentication is still going to be handled by AD and unless the curious user already has a way to successfully authenticate against your AD then it's rather useless for him to hookup into that document.
Could they potentially create an app that uses your authentication protocol? Sure, but what would be the point if nobody can actually authenticate against it. Allowing this sort of behavior to happen is one of the points of ADFS.
UPDATED: We are building Mobile apps on Windows, IOS & Android platform to generate OTP (one time password) for a regulated system. The system will prompt challenge phrase when user attempt to login and the displayed challenge need to be keyed into mobile App to generate the OTP. The generated OTP is then entered back into System to successfully login.
So far the requirements for mobile OTP generate app is good as we can expose a service to generate OTP with required security.
But, we have a wired requirement to support the same feature with offline capability where mobile has no internet connectivity. The only choice we know is to embed the OTP algorithm & key into app and apply suitable security mechanism. Algorithm is custom built propitiatory algorithm and without compromising security we need to achieve the offline capability. Is that a good approach to embed algorithm & key into app to enable offline capability? What is the recommended solution.
I have no idea what you mean by "Enterprise will expose API".
But, you will need something tied to the physical phone device, like the SIM module (i.e. the phone number) or an app with secure/private storage for two-factor to work.
An API exposed on the internet, without a strong link to the authentication token (phone), is not secure.
So, I guess the only answer is: Yes, you should implement the "OTP algorithm" in the app. The app must store the shared secret in a private storage that is not (easily) accessible to other apps. Then, depending on the kind of OTP, you need to provide some means of synchronization between the app and the server. For Google's Authenticator this is just establishing a common timebase because the "OTP" is not strictly one-time but changes (only) depending on the current date+time; hence the current time becomes the "challenge" the server implicitly poses for the client to return the correct response. The good thing is that you don't need access to the internet to know the current time in your app. You only need to synchronize the timebase now and then to make sure the clock in your app does not differ too much from the server's.
The server could instead also send an explicit challenge, like a sequential number. This challenge would be displayed to the user attempting to log-in, the user would have to type the number into the app and return the app's answer to the server.
Many more options are available, but the bottom line is: To provide reasonable security, the OTP must be calculated on the phone.
I am in process of designing a SaaS application over PaaS (Google App Engine).
My SaaS will have two user interfaces:
Web Based
Mobile App based
Web based would be feature-rich whereas Mobile app would have essential and/or frequently used features.
Mobile app would invoke RESTful services to perform business logic.
This SaaS would target mainly individuals using Mobile Apps; however, there could a use-case wherein these individuals could form a group and operate as a company.
So with that in mind, I am considering two entities: Account (Tenant) and User.
I am considering having many-to-many relationship between these two entities as one user could be part of multiple Accounts (unlikely but can’t be ruled out) and of course, one account can have multiple users.
I would like to know the best practices for authentication under such scenario:
Should I use Google's provided Authentication or should I implement my own authentication? (I am still exploring OAuth and Google's authentication offering.)
I think, for web-based interface, username/password over SSL would suffice. But, not sure, can this be applied to mobile app?
Can I avoid a situation wherein I have to store credentials in mobile app?
Thanks in advance for any help you can provide on this.
A
Having just completed my first project using Google App Engine, I can say that I ran into alot of the questions that you have. I'll try to explain my approach to each point and also approach it from your perspective as well.
Authentication - Generally using Google's auth would be the easiest route, but you would still have to implement a custom adaptation in order to work with the "company"/"group" concept. Implement in the datastore/whatever database you prefer to use an entity called "Groups" which have a list of google users... this way users can belong to many groups.. then you just search by property (user) to get all groups they belong to. I implemented my own authentication system for unrelated reasons.
Google App Engine comes with SSL/HTTPS support for its own domains. You can add in your own custom domain with SSL support as well. You can use SSL through native apps or mobile web apps additionally. I simply used the native support that came with it.
Yes and no. You will always have to store the credentials somewhere. Maybe it wont be in your apps code/directly connected to your app (Google auth would be an example). But somewhere, on your phone, the credentials WILL reside. They may be encrypted/obfuscated, but they will be there. So either have your user enter them in everytime, or save them/use the ones provided by the phone. For myself, .NET provided a nice way of storing credentials in a secure fashion (non-plain-text) for each user's machine.