Documentation advises not to do so, but what if I make a part of the database publically readable and writeable? What harm could it cause?
Anyone who knows the name of your project could read and write the data in your database at those locations. The name of your project is generally public information to anyone who has a copy of your Android, iOS, or web app.
Obviously, this could cause problem with the data in your app. Also, if your project has billing enabled, you could end up paying for all the storage and bandwidth that could be used by a potential malicious attacker.
Related
Could someone please explain to me why a bad actor could not create the following disruption for potential new users to my app?
The bad actor:
Obtains a list of emails from the dark web or some other nefarious source.
Acquires my Firebase keys by inspecting my app javascript -- yes my app is minified, but it would still be possible.
inserts malicious javascript code into my app sources on their local browser. The malicious code uses the Firebase sdk and my app keys to create accounts for each email address.
While there is no possibility that the bad actor could gain access to validated accounts;
nevertheless, creating these accounts would generate unsolicited email verification requests to the owners of the emails and it would also interfere with a smooth account-creation experience for those users when they actually do want to signup.
Am I missing something here?
firebaser here
As Dharmaraj also commented: the Firebase configuration that you include in your app is used to identity the project that the code should connect to, and is not any kind of security mechanism on its own. Read more on this in Is it safe to expose Firebase apiKey to the public?
You already in your question noted that creating a flurry of accounts doesn't put user data at risk, which is indeed also correct. Creating an account in your project does not grant the user any access to other user accounts or data in your project yet. If you use one of Firebase's backend services, you should make sure that your security rules for that service don't do this either.
The final piece of the puzzle is that Firebase has many (intentionally undocumented or under-documented) safe guards in place against abuse, such as various types of rate limits and quotas.
Oh, and I'd recommend using the local emulators for most of your testing, as that'll be faster, doesn't risk accidentally racking up charges due to a quick coding mistake, and (most relevant here) doesn't have the rate limits in place that are affecting your e2e test.
I have been introduced to Firebase a few days ago. Since then I have been trying to discover more features and usage of Firebase, in particular, the usage of the Firestore/Realtime Database.
However, as I am reading into more details, I start to think of some questions. I hope someone that is familiar with Firebase can help me answer them
As for User authentication, I understand that I can use Firebase Authentication where I won't see their real password. However, technically, everything that user stores in my Firestore would be visible to me since I am the owner of the Firebase.
For example, if I were to develop a note/chat app, in which the user can access their notes/chat on the iOS app and also Android. That means all their notes data would be saved in my database. If it happens to contain some private data, then I would be able to read it?
Even if I set security rules, that would be only facing client-side, whereas, for me, the owner of the entire firebase data, I could see the whole thing. Surely, as a customer, you won't want to use an app knowing that I can see everything you write
I am not sure if what I said is true or not. If true, is there a possible solution?
Both of your statements are correct. This happens in most of the apps-websites, the admin or some core developers have full access to the data. That's why privacy policy and GDPR exist. You must specify what data you collect and for what reason. If you intend to use your user data for any other reason you must inform them. Be aware that if you disclose any user information without his permission you can be held liable.
I am creating an Unity game where I want to have global top 50 score list with usernames. I use Firebase realtime database. There is no need for user to authenticate. I am not that familiar with database security and pretty beginner with this concept. I am using Rest Api from Unity Asset store because it was pretty easy to send and get data from databse.
How can I be sure that every score sent to database is from my app?
Add a dedicated user with password to your database
Somewhere in you app, add those credentials e.g. in a ScriptableObject / in some component
Always use those credentials to authenticate
Note that your app can still be decompiled and thereby cheated.
You can at least make it more difficult by encrypting the data etc.
The only way really around is to have an account and sessioning server to assure a user is locked in with a valid session.
If you don't use Firebase Authentication, you can't restrict who can access your database. Anyone will be able to issues a query, and they can even do it using the Realtime Database REST API. All they have to know is the name of your project.
Even if you do use Firebase Authentication, anyone may still effectively authenticate and access the database outside of your app using other public APIs.
My experience is that you can't stop dedicated "users" from cheating global at high scores. I made a small handfull of trivial games for windows phone with global top 50. Even if your game is unpopular, and you obfuscate your code, and you are on an unpopular platform, and you encrypt your network traffic: somebody is going to jailbreak their phone, decompile your app, and inject their own high score into your game before high scores are sent to the global list. The only way I ever came up with to combat this was to keep track of play sessions -on the server- to make sure their scores were theoretically possible based on how long they were playing.
Disclaimer: I don't know anything about Firebase
From what I can tell, you will need to set up access for Default and Public sections of your configuration to tell the database who can and cannot access your database. Here's their documentation on Get Started with Database Rules.
In general database access, no one should know the details of your connection to a database, so all calls should only ever come from your app.
Let's say I'm developing app like Instagram: for iOS, Android and Web. I decided to use Google Firebase as it really seems to simplify the work.
The features user needs in the app are:
Authorization/Registration
Uploading photos
Searching for other people, following them and see their photos
I come from traditional "own-backend" development where I do need to setup a server, create database and finally write the API to let the frontend retrieve the data from the server. That's the reason why it's unclear to me how it all works in Firebase.
So the question is how can I create such app:
Should I create my own API with cloud functions? Or it's ok to work with the database directly from the client-side?
If I work with the database directly why do I need cloud functions? Should I use them?
Sorry for such silly questions, but it is really hard to get from scratch.
The main difference between Firebase and the traditional setup you describe is that with Firebase, as far as the app developer is concerned, the client has direct access to the database, without the need for an intermediate custom API layer. Firebase provides SDKs in various languages that you would typically use to fetch the data you need / commit data updates.
You also have admin SDKs that you can use server-side, but these are meant for you to run some custom business logic - such as analytics, caching in an external service, for exemple - not for you to implement a data fetching API layer.
This has 2 important consequences:
You must define security rules to control who is allowed to read/write at what paths in your database. These security rules are defined at the project level, and rely on the authenticated user (using Firebase Authentication). Typically, if you store the user profile at the path users/$userId, you would define a rule saying that this node can be written to only if the authenticated user has an id of $userId.
You must structure your data in a way that makes it easily readable - without the need for complex database operations such as JOINs that are not supported by Firebase (you do have some limited querying options tough).
These 2 points allow you to skip the 2 main roles of traditional APIs: validating access and fetching/formatting the data.
Cloud functions allow you to react to data changes. Let's say everytime a new user is created, you want to send him a Welcome email: you could define a cloud function sending this email everytime a new node is appended to the users path. They allow you to run the code you would typically run server-side when writes happen, so they can have a very broad range of use-cases: side-effects (such as sending an email), caching data in an external service, caching data within Firebase for easier reads, analytics, etc..
You don't really need a server, you can access the database directly from the client, as long as your users are authenticated and you have defined reasonable security rules on Firebase.
In your use case you could, for example, use cloud functions to create a thumbnail when someone uploads a photo (Firebase Cloud Functions has ImageMagick included for that), or to denormalize your data so your application is faster, or to generate logs. So, basically you can use them whenever you need to do some server side processing when something changes on your database or storage. But I find cloud functions hard to develop and debug, and there are alternatives such as creating a Node application that subscribes to real time changes in your data and processes it. The downside is that you need to host it outside Firebase.
My answer is definitely NOT complete or professional, but here are the reasons why I choose Cloud Functions
Performance
You mentioned that you're writing an instagram-like mobile device app, then I assume that people can comment on others' pictures, as well as view those comments. How would you like to download comments from database and display them on users' devices? I mean, there could be hundreds, maybe thousands of comments on 1 post, you'll need to paginate your results. Why not let the server do all the hard work, free up users' devices and wait for the results? This doesn't seem like a lot better, but let's face it, if your app is incredibly successful, you'll have millions of users, millions of comments that you need to deal with, server will do those hard jobs way better than a mobile phone.
Security
If your project is small, then it's true that you won't worry about performance, but what about security? If you do everything on client side, you're basically allowing every device to connect to your database, meaning that every device can read from/write into your database. Once a malicious user have found out your database url, all he has to do is to
firebase.database().ref(...).remove();
With 1 line of code, you'll lose all your data. Okay, if you say, then I'll just come up with some good security rules like the one below:
This means that for each post, only the owner of that post can make any changes to it or read from it, other people are forbidden to do anything. It's good, but not realistic. People are supposed to be able to comment on the post, that's modifying the post, this rule will not apply to the situation. But again, if you let everybody read/write, it's not safe again. Then, why not just make .read and .write false, like this:
It's 100% safe, because nobody can do anything about anything in your database. Then, you write an API to do all the operations to your database. API limits the operations that can be done to your database. And you have experience in writing APIs, I'm sure you can do something to make your API strong in terms of security, for example, if a user wants to delete a post that he created, in your deletePost API, you're supposed to authenticate the user first. This way, 'nobody' can cause any damage to your database.
I understand the principle and the need for security rules, and I am intending to write them as required.
My questions is in the instance that I forgot/missed to put a rule in for a particular branch in the JSON tree. how will a user/anyone know the paths of my JSON tree to go go malicious adds/removes in the JSON tree?
In my example, I have an iOS app that has the UI, numerous viewControllers, that do all the add/remove of any info/objects to the Firebase backend. How would an end user even know how to manipulate the paths in my Firebase backend when they are not exposed to my Firebase structure?
For iOS apps security isn't as big of a deal, but if someone managed to get a hold of your source code or your firebase's configuration information then they'd be able to set up a dummy project hooked up to your database and be able to manipulate your unsecured branches. For non-iOS apps security is very important as it's pretty straight forward to acquire a firebase's config info.