I am working on a mobile app, where users have complex profiles and can chat to each other. So right now I am using firebase's onSnapshot() listener in the frontend code to get the real-time data ASAP. I am thinking whether its secure enough? Would it be better to move it to the backend server? Than fetching real-time would be way more complex I guess. Could you tell me what are the dangers of keeping these listeners on frontend? Thank you.
Could you tell me what are the dangers of keeping these listeners on
frontend?
The standard way for securing your database (as well as Cloud Storage buckets) is by using Security Rules.
In particular the documentation explains that:
Every database request from a Cloud Firestore mobile/web client
library is evaluated against your security rules before reading or
writing any data. If the rules deny access to any of the specified
document paths, the entire request fails.
This evaluation is totally independent from the way you query the database: Whether you query it via a realtime listener or via a one time fetch (using one of the get() methods) the database request is evaluated against your security rules.
So, in conclusion, if you use Security Rules, there is no "danger" to use some realtime listeners.
I am thinking whether its secure enough? Would it be better to move it
to the backend server?
Based on the details you share in your question there is no reason, IMO, to switch to a back-end approach (like using Cloud Functions to read the database). One reason could be that your security logic is too complex to be implemented with the security rules language/model. But note that you can build complex logic in Security Rules, for example by basing them on Custom Claims or other Firestore documents.
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 am using different third party API keys in my reactjs-firestore project. But I can't find a way to secure them in firebase hosting. How can I hide these API keys in firebase hosting?
For example, in Netlify hosting services they provide environment variables feature which can be used to secure the API keys.
that is I can just store the API keys in the variables in netlify and it will be retrieved from there which will be secured.
But in firebase how do I do this?
I can't seem to find a similar setting wherein I can store the keys as environment variables in the hosting services.
if there is no such feature is there another way to secure these API keys?
and for the firebase API keys,
I have already read some answers and understood that firebase API keys will not be hidden.
is there at least some way to secure these firebase API keys to just one secured URL at least? (I know that writing security rules is the best approach but am trying to find other options as well).
I can't seem to find a way to secure firebase project API key usage to one secured URL.
I have tried to find ways to secure the API key but I haven't been successful.
below is how I retrieve data in reactjs code
axios.post(`https://data.retrieval.com/1/data?key=API_KEY`, data)
I am trying to hide the API_KEY in the production code
I want to secure third party API keys in my hosted website.
and also restrict my firebase project API key to just one secure URL.
am not able to do this now.
any suggestions or solutions?
Thank you for trying to help.
and thank you for your time
If you're using the API key in client-side code, there is always the chance that a malicious user can find the key and abuse it. The only way to protect against this is to not use the API key in client-side code, or to have a backend system that can protect access based on something else (such as Firebase's server-side security rules).
Since your backend system likely doesn't have such a security model, you'll typically have to wrap their API in your own middleware that you host in a trusted environment such a server you control, or Cloud Functions. That's then where you ensure all access to the API is authorized, for example by setting up your own security system.
Not sure if this help, but my Firebase Cloud Function use this.
Create your secret by
firebase functions:config:set secret.API_KEY="THE API KEY"
Access your secret by using functions.config().secret.API_KEY
Note: This should only use for server use case, not in the client code. For server I meant Firebase Cloud Function or your backend.
The safe way I've found to store your third-party keys is using the Google Secrets Manager. It is now baked into the Firebase Functions SDK and works very well. You can find the information here, under the section titled "Store and access sensitive configuration information".
Two things worth mentioning:
There is a small bug in the syntax example, they forgot to add the https before onCall.
You'll need to give the service account which runs the cloud function when deployed access to the secrets. Here are the official docs on how to do that. If you are deploying through Firebase, you'll want to look for the service account whose address is [project-name]#appspot.gserviceaccount.com. If you have any doubts about which service account is running the Cloud Function, look under the Details tab in the Cloud Functions section of Google Cloud Platform and it will show you that information. Also, under the Variables tab, you can see what secrets your Cloud Function has access to.
This process makes it really easy to manage third-party keys as you can manage them at your project level and not have to worry about them being stored else where or needing to manage .env files. It also works with the Firebase Emulators and uses the credentials of the user running the emulators for access.
I am new to web development, and have seen posts such as these . If one is using AWS and is connecting to an AWS rds instance through Node, is that still considered a direct connection as opposed to a web service?
You're probably going to get a bunch of conflicting opinions on this. My personal opinion is a web service in front of your database makes sense in some scenarios. Multiple applications connecting to the web service instead of directly to the db gives several advantages, security, caching, etc.
That being said, if this is just a single app then most of those advantages disappear and in fact just make things more complex for you. You're going to have to setup your web service for the db as well as your actual code.
If one is using AWS and is connecting to an AWS rds instance through Node, is that still considered a direct connection as opposed to a web service?
No, if Node.js is running on a server or in "serverless" containers (e.g. AWS Lambda) that is not a direct connection. That is a web service, and that's what you want.
A direct connection means the app connects to the database itself... but that requires embedding credentials in the app.
You do not want to embed anything in your app that you would not willingly hand over to an arbitrary user -- such as database credentials and API keys -- because you cannot trust that the app won't be reverse-engineered.
You should design the app in such a way that you would have no security concerns if the entire source code of the app were exposed, because knowing everything about the app's internals would give a malicious actor no valuable information. How? The code on the server side (e.g. in Node.js) should treat every request from the app as potentially suspicious, untrustworthy, etc., and validates every request to do anything.
This layer of separation is one of the strongest reasons why you never give the app direct access to the database. Code running in a trusted place -- your web server/API layer -- needs to vet every database interaction. This topology also decouples the app user from tying up resources on the database server when not actually interacting with the database, which is far less practical with a direct connection.
I've been thinking about this quite a while and it's bugging my head off, lets say we have a website a mobile app and a database.
Usually when we develop our websites we pretend to store our database credentials in a configuration file and connect the website directly to the database without using a multi-tier architecture, but when it comes to a mobile application such Android or iOS this applications can be engineer reversed meaning that there's a risk of exposing your database credentials.
So I started thinking about this multi-tier architecture and kind of thinking about how Facebook and other social network do their job, they usually make an API and use a lot of HTTP Requests.
Usually social networks APIs have a app_id and a secret_key, this secret key would be used to increase the safety of the application but I'm thinking about how could I store these keys inside my application since I would go back to the begining of my discussion, if I was to use Java I could use the Java Preference Class but that isn't safe either has I saw in this question, plus I would need to make sure my HTTP Requests are CSRF safe.
So, how could I store these keys inside my app? What's the best way to do it, since hard-codding it's out of the question.
You should always require users to log in - never store credentials or private keys in an app you'll be distributing. At the very least, don't store them unless they're specific to the user who has chosen to store them after being validated.
The basic idea is that the user should have to be authenticated in some manner, and how you do that is really too broad to cover in a SO answer. The basic structure should be:
User asks to authenticate at your service and is presented with a challenge
User responds to that challenge (by giving a password or an authentication token from a trusted identity provider).
Service has credentials to access the database, and only allows authenticated users to do so.
There are entire services out there built around providing this kind of thing, particularly for mobile apps.
You might store the users own credentials on the device, and if so it should be encrypted (but you're right, a malicious app could potentially pick them up).
Bottom line: never distribute hard coded access to a database directly.