I think from searching the web this is not technically possible but I want to ask again in case I'm missing something.
I have an app that uses Firebase. Reading and writing is locked down through security rules for authorised users only but there's certain information I want unauthorised users to be able to access (so I don't have to put a login wall in front of them, influencing churn).
What I want to know is, is there any way of locking down this read access that only my app can call the DB? I know I can lock down domains to prevent someone writing localhost scrapers but what's to stop someone cloning and re-skinning an app and pointing it to the same back end? Is it possible to achieve this using your certificates fingerprint?
There is no way to limit access to your database to just your app. That just doesn't match with the cloud-based nature of the Firebase APIs. Anyone that knows the URL of your database can in in principle access it, and security rule are the way to ensure all access is authorized.
Note that security rules are not an all-or-nothing approach: you can require sign-in for some parts of your database, while leaving other parts publicly readable. But you can't make the publicly readable parts only be readable by your own app.
Some previous questions on the same topic:
how to make sure only my own website (clientside code) can talk to Firebase backend? (pretty much my go-to answer for this)
How to allow only my app to access firebase without a login?
Restrict Firebase database access to one Android app
How to allow only my app to access firebase without a login?
Update: since May 2021 you can actually restrict access to just users of your App by implementing Firebase App Check.
I have found a solution that maybe helps you or anyone that have a similar question. I answered it in this question:
Restricting Cloud Firestore to a specific domain
Related
Disclaimer: I am new to mobile app development and have little to no knowledge on authentication systems
Normally, when my mobile app makes https calls to my backend server, I know that I cannot trust that these calls to my server came from my app, as anyone can make https requests to my backend server. Even if I give the app a secret key, it is still possible for a hacker to obtain the key and include it in https requests. Therefore, I will not allow https requests to accomplish whatever it wants on the server; rather, I will limit the request to doing only what a user can normally do with their own data – delete their OWN posts, edit their OWN profile, and so on.
Does Firebase work the same way? I saw this StackOverflow thread regarding OAuth consumer secrets, and how they can be compromised and used to imitate a mobile app.
Is this also the case for Firebase?
Can a malicious user theoretically obtain whatever keys/secrets Firebase gave to my mobile app, and use that to emulate requests from my app to Firebase? For example, could they create new users and cause de-syncing issues with my own backend database?
If so, how can I prevent it?
Thanks.
Does Firebase work the same way?
Firebase works in whatever way you program it. Normally you do not put private keys in software that you distribute to end users. The recommended approach is documented very well - use Firebase Auth ID tokens to indicate who is making the call, and use code on your backend to figure out if they should be able to do the work they are requesting. This is what happens with direct database access from your app, but you have to write security rules to protect data according to your requirements.
If you are passing tokens yourself to your own backend, it is up to you to revoke any refresh tokens that you find to be compromised. You cannot fully stop hackers from compromising a system that stores user tokens on devices that you don't control. All you can do is make it hard for them to do so.
Can a malicious user theoretically obtain whatever keys/secrets Firebase gave to my mobile app
Yes, that's why you don't put secrets in code that you distribute to end users. The Firebase config that you're asked to add to your app is not considered private.
See also:
Is it safe to expose Firebase apiKey to the public?
I think from searching the web this is not technically possible but I want to ask again in case I'm missing something.
I have an app that uses Firebase. Reading and writing is locked down through security rules for authorised users only but there's certain information I want unauthorised users to be able to access (so I don't have to put a login wall in front of them, influencing churn).
What I want to know is, is there any way of locking down this read access that only my app can call the DB? I know I can lock down domains to prevent someone writing localhost scrapers but what's to stop someone cloning and re-skinning an app and pointing it to the same back end? Is it possible to achieve this using your certificates fingerprint?
There is no way to limit access to your database to just your app. That just doesn't match with the cloud-based nature of the Firebase APIs. Anyone that knows the URL of your database can in in principle access it, and security rule are the way to ensure all access is authorized.
Note that security rules are not an all-or-nothing approach: you can require sign-in for some parts of your database, while leaving other parts publicly readable. But you can't make the publicly readable parts only be readable by your own app.
Some previous questions on the same topic:
how to make sure only my own website (clientside code) can talk to Firebase backend? (pretty much my go-to answer for this)
How to allow only my app to access firebase without a login?
Restrict Firebase database access to one Android app
How to allow only my app to access firebase without a login?
Update: since May 2021 you can actually restrict access to just users of your App by implementing Firebase App Check.
I have found a solution that maybe helps you or anyone that have a similar question. I answered it in this question:
Restricting Cloud Firestore to a specific domain
I think from searching the web this is not technically possible but I want to ask again in case I'm missing something.
I have an app that uses Firebase. Reading and writing is locked down through security rules for authorised users only but there's certain information I want unauthorised users to be able to access (so I don't have to put a login wall in front of them, influencing churn).
What I want to know is, is there any way of locking down this read access that only my app can call the DB? I know I can lock down domains to prevent someone writing localhost scrapers but what's to stop someone cloning and re-skinning an app and pointing it to the same back end? Is it possible to achieve this using your certificates fingerprint?
There is no way to limit access to your database to just your app. That just doesn't match with the cloud-based nature of the Firebase APIs. Anyone that knows the URL of your database can in in principle access it, and security rule are the way to ensure all access is authorized.
Note that security rules are not an all-or-nothing approach: you can require sign-in for some parts of your database, while leaving other parts publicly readable. But you can't make the publicly readable parts only be readable by your own app.
Some previous questions on the same topic:
how to make sure only my own website (clientside code) can talk to Firebase backend? (pretty much my go-to answer for this)
How to allow only my app to access firebase without a login?
Restrict Firebase database access to one Android app
How to allow only my app to access firebase without a login?
Update: since May 2021 you can actually restrict access to just users of your App by implementing Firebase App Check.
I have found a solution that maybe helps you or anyone that have a similar question. I answered it in this question:
Restricting Cloud Firestore to a specific domain
I developed a flutter app,
I use Firebase as my DB, which means that any user can write and read from my DB,
I'm getting the following email every couple of hours.
[Firebase] Your Cloud Firestore database has insecure rules
We've detected the following issue(s) with your security rules:
any user can read your entire database
any user can write to your entire database
Which is exactly what I want, since I want my app to be available to unregistered users.
Did I missed something? is my app is actually insecure?
The access to the DB is done through the app with filters only user specific data.
Is there a way to make my more secure, and keeping it available for unregistered users?
I also not sure why allowing only registered user will make it insecure, since any one can register to the app with a click of a button.
Please shed some light on this issue.
You will definitely need to learn how to use security rules. A full discussion is beyond the scope of a single answer, but you should know that security rules allow you to specify who (signed in through Firebase Auth) can read and write which documents and collections. Not using security rules at all is a massive security hole.
The video in the following documentation explain it in a very simple way
https://firebase.google.com/docs/firestore/security/get-started#writing_rules
The bottom line is that you must auth your users, and then use security rules for filtering the data, inorder for your data to be secured.
Using insecure rule should be done only for testing s
I am learning Flutter by following Codelab Firebase Tutorial and developing test Android app almost similar to this. Users save their baby name and others vote their favorites which updates Votes count in database. Based on this, I have few questions related to Firebase Security.
App does not currently have any Firebase Authentication. Is it necessary to have Firebase Auth seeing users who will just vote does not need to have any kind of registration.
Can someone decompile my app and get google-services.json file? If yes, will that allow them to use this file in their app and mess my database?
How much secure is my app from non-users like I mentioned in above point if I do not include firebase auth and keep security rules to default (read, write all)?
Apologies, If I failed to convey my point properly as I am still in learning stages of App development.
You must be using Firebase Authentiction if you want per-user read/write restrictions. If you aren't using it, you can only restrict what anyone in the world can do with public access.
Yes, anyone can get the values from your google-services.json file. They are added to your app as string resources. No, it doesn't allow anyone to access everything. What you're asking here is very common, try doing some searches for that. For example this.
If you use security rules that allow all read and write access, anyone with an internet connection will be able to read and write your database. This is not really acceptable in most cases.