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 an 3rd Party API I'm wanting to use from my Silverlight 4 Application. It's interface is simply a web request (NOT A WEB SERVICE!) with form variables. According to everything I've read, this is not possible because of security issues? What security issues? Is there no way to do this? I can understand not allowing this with web services, but with simple web requests?
I cannot use my RIA Services gateway because the data is VERY sensitive and I cannot (and do not want to) transmit it under my own SSL cert. This is RIDICULOUS!
The same security issues apply in Adobe Flash. In JavaScript, it's not possible at all.
For Silverlight, the website root must contain a clientaccesspolicy.xml permitting the call.
http://msdn.microsoft.com/en-us/library/cc197955%28v=vs.95%29.aspx
To stop Cross Site Request Forgery (XSRF). Without this measure, what's to stop an attacker from issuing requests to online banking sites (or any site) on the users behalf? Exploiting the fact he may have cookies stored which will allow the request to go through.
It's too bad the internet has turned into an assumed guilty until proven innocent situation, as I could see many useful, non-malicious, uses for sending web requests.
I am going to be developing an application for work, and I am trying to decide whether to use Silverlight Business App or Asp.Net Web App. My manager is concerned about the performance and download time it would take if I created the entire application as a Silverlight app, with authentication. I have been playing around with some tutorials over the last week trying to get a perspective on my situation and have come up with a design question I need to ask those that are more experienced than me.
Is it possible to use a Asp.Net application and just embed a silverlight application in one of the pages that will be used inside a folder that is configured with the roles authorization? And if so, would it be possible to get user credentials from the client silverlight app without passing them through the initParams.
I understand that I can set the authentication to "useCookies", so I was thinking I would be able to get the cookie on the client and hopefully get a property verifying if the user is authenticated.
Also, would this be a risky practice? Thanks for any advice and direction.
There are a few approaches you could take. While I know you don't want to expose the credential in init params, you could generate a "ticket" (claims-based authentication) for the credential, and include the ticket (for example, a GUID) in the init params. When the Silverlight application launches, it would consume the ticket, possibly validating it via a secured web service call, and the ticket would no longer be valid so even if someone spoofed it or viewed the source, it couldn't be used.
Quite a bit depends on your architecture. For example, if you are using the roles-based authentication, and most of the business logic and/or decision making is based on web service calls, the web services can use HttpContext.Current.Identity to validate the user. Even if someone opens the Silverlight application, any service calls would fail unless they were appropriately authenticated. Otherwise, I would either go with passing a ticket so Silverlight trustst the user is valid (you can create a service that accepts the Guid and returns the role information) or have the user log in from Silverlight (you have a service facing in front of the authentication mechanism and then return a ticket and/or role information).
It gets even more interesting if you decide to use WCF RIA, check out these examples for baked-in authentication:
http://code.msdn.microsoft.com/RiaServices/Release/ProjectReleases.aspx?ReleaseId=2661
1.) It's absolutely possible to embed a Silverlight xap on an ASP.NET page.
2.) As far as credentials, using cookies could work, or you could pass in a token over initparams and validate that token via a web service to see if the user is valid
It's always a risk passing credentials around, especially when it's running on a clients computer. That said, Silverlight buys you a lot, so don't let the challenge of authentication hold you back.
I have googled a bit for how I should handle security in a web service application when the application is basically the data repository for a Silverlight application, but have gotten inconclusive results.
The Silverlight application is not supposed to have its own user authentication, since it will be reachable only through a web application that the user have already authenticated to get into.
As such, I was thinking I could simply add a parameter to the SL application that is a cookie-type value, with a certain lifetime, linked to the user in the database. The SL application would then have to pass this value alongside other parameters to the web services. Since the web service is hopefully going to be a generic web service endpoint, few methods, adding an extra parameter at this level will not be a problem.
But, am I supposed to roll this system on my own? It sounds to me as this isn't exactly new features that nobody has considered before, so what are my options?
First of all use SSL for the service. Otherwise users will be able to capture all the parameters passed to the service. It's still possible to see it in case of https but it will be a little bit more difficult.
Also, consider using Message Inspector for adding custom headers to the messages which you will validate on the server. This way you will not need to add extra parameters.
We have a Silverlight app which we wrote which calls a Silverlight-enabled data service. The Silverlight app cannot require a login, as it is required to present data to the unauthenticated public.
We have some schmoe who took the time to examine our Silverlight app, one way or another figure out what service it is calling, and then wrote his own client to slurp off the data so he can post it on his site and pretend like it is his. We need to prevent this.
How can i limit my data service somehow to ONLY accept requests from my silverlight app? I tried using the allow-from domain uri setting in the clientaccesspolicy.xml file to limit access to the service only from the domain in which the silverlight app sits (say mydomain.com). This did absolutely nothing though, and the service is still serving up requests to clients from outside the domain. (I tested this by putting my SL app on a different domain under our control).
What is the proper/best/most effective way to limit the data service so only our app can use it? Thanks!!!
I'm using SL 3 and .NET 3.5.
The clientaccesspolicy.xml tells the Silverlight application which Webservice it can consume. Not preventing people accessing the Webservice.
You can try using a authentication login even though its not required. This prevents 'schmoes' accessing your webservice.
Also use Dotfuscator to prevent 'schoes' to disassemble your Silverlight application and acquire the login.
Silverlight webservice security follows the same patterns you'd use for ASP.NET security, especially services exposed to AJAX. The best way to do make use of ASP.NET's authentication.
RIA Services is an even better way to handle this. It rides on top of the ASP.NET authorization, but validates on both the client and server-side automatically to combat service spoofing. It let you take care of both client and server-side authorization by adding attributes to your methods indicating that the method requires authorized access, and by which groups or users if you need to be specific.
In addition to wire-side security and obfuscation, remember that clients can attach a debugger to Silverlight applications running in their browser. See this example from MSDN Magazine's Security IQ Test, November 2008.