The Firebase Web-App guide states I should put the given apiKey in my Html to initialize Firebase:
// TODO: Replace with your project's customized code snippet
<script src="https://www.gstatic.com/firebasejs/3.0.2/firebase.js"></script>
<script>
// Initialize Firebase
var config = {
apiKey: '<your-api-key>',
authDomain: '<your-auth-domain>',
databaseURL: '<your-database-url>',
storageBucket: '<your-storage-bucket>'
};
firebase.initializeApp(config);
</script>
By doing so, the apiKey is exposed to every visitor.
What is the purpose of that key and is it really meant to be public?
The apiKey in this configuration snippet just identifies your Firebase project on the Google servers. It is not a security risk for someone to know it. In fact, it is necessary for them to know it, in order for them to interact with your Firebase project. This same configuration data is also included in every iOS and Android app that uses Firebase as its backend.
In that sense it is very similar to the database URL that identifies the back-end database associated with your project in the same snippet: https://<app-id>.firebaseio.com. See this question on why this is not a security risk: How to restrict Firebase data modification?, including the use of Firebase's server side security rules to ensure only authorized users can access the backend services.
If you want to learn how to secure all data access to your Firebase backend services is authorized, read up on the documentation on Firebase security rules. These rules control access to file storage and database access, and are enforced on the Firebase servers. So no matter if it's your code, or somebody else's code that uses you configuration data, it can only do what the security rules allow it to do.
For another explanation of what Firebase uses these values for, and for which of them you can set quotas, see the Firebase documentation on using and managing API keys.
If you'd like to reduce the risk of committing this configuration data to version control, consider using the SDK auto-configuration of Firebase Hosting. While the keys will still end up in the browser in the same format, they won't be hard-coded into your code anymore with that.
Update (May 2021): Thanks to the new feature called Firebase App Check, it is now actually possible to limit access to the backend services in your Firebase project to only those coming from iOS, Android and Web apps that are registered in that specific project.
You'll typically want to combine this with the user authentication based security described above, so that you have another shield against abusive users that do use your app.
By combining App Check with security rules you have both broad protection against abuse, and fine gained control over what data each user can access, while still allowing direct access to the database from your client-side application code.
Building on the answers of prufrofro and Frank van Puffelen here, I put together this setup that doesn't prevent scraping, but can make it slightly harder to use your API key.
Warning: To get your data, even with this method, one can for example simply open the JS console in Chrome and type:
firebase.database().ref("/get/all/the/data").once("value", function (data) {
console.log(data.val());
});
Only the database security rules can protect your data.
Nevertheless, I restricted my production API key use to my domain name like this:
https://console.developers.google.com/apis
Select your Firebase project
Credentials
Under API keys, pick your Browser key. It should look like this: "Browser key (auto created by Google Service)"
In "Accept requests from these
HTTP referrers (web sites)", add the URL of your app (exemple: projectname.firebaseapp.com/* )
Now the app will only work on this specific domain name. So I created another API Key that will be private for localhost developement.
Click Create credentials > API Key
By default, as mentioned by Emmanuel Campos, Firebase only whitelists localhost and your Firebase hosting domain.
In order to make sure I don't publish the wrong API key by mistake, I use one of the following methods to automatically use the more restricted one in production.
Setup for Create-React-App
In /env.development:
REACT_APP_API_KEY=###dev-key###
In /env.production:
REACT_APP_API_KEY=###public-key###
In /src/index.js
const firebaseConfig = {
apiKey: process.env.REACT_APP_API_KEY,
// ...
};
I am not convinced to expose security/config keys to client. I would not call it secure, not because some one can steal all private information from first day, because someone can make excessive request, and drain your quota and make you owe to Google a lot of money.
You need to think about many concepts from restricting people not to access where they are not supposed to be, DOS attacks etc.
I would more prefer the client first will hit to your web server, there you put what ever first hand firewall, captcha , cloudflare, custom security in between the client and server, or between server and firebase and you are good to go. At least you can first stop suspect activity before it reaches to firebase. You will have much more flexibility.
I only see one good usage scenario for using client based config for internal usages. For example, you have internal domain, and you are pretty sure outsiders cannot access there, so you can setup environment like browser -> firebase type.
The API key exposure creates a vulnerability when user/password sign up is enabled. There is an open API endpoint that takes the API key and allows anyone to create a new user account. They then can use this new account to log in to your Firebase Auth protected app or use the SDK to auth with user/pass and run queries.
I've reported this to Google but they say it's working as intended.
If you can't disable user/password accounts you should do the following:
Create a cloud function to auto disable new users onCreate and create a new DB entry to manage their access.
Ex: MyUsers/{userId}/Access: 0
exports.addUser = functions.auth.user().onCreate(onAddUser);
exports.deleteUser = functions.auth.user().onDelete(onDeleteUser);
Update your rules to only allow reads for users with access > 1.
On the off chance the listener function doesn't disable the account fast enough then the read rules will prevent them from reading any data.
I believe once database rules are written accurately, it will be enough to protect your data. Moreover, there are guidelines that one can follow to structure your database accordingly. For example, making a UID node under users, and putting all under information under it. After that, you will need to implement a simple database rule as below
"rules": {
"users": {
"$uid": {
".read": "auth != null && auth.uid == $uid",
".write": "auth != null && auth.uid == $uid"
}
}
}
}
No other user will be able to read other users' data, moreover, domain policy will restrict requests coming from other domains.
One can read more about it on
Firebase Security rules
While the original question was answered (that the api key can be exposed - the protection of the data must be set from the DB rulles), I was also looking for a solution to restrict the access to specific parts of the DB.
So after reading this and some personal research about the possibilities, I came up with a slightly different approach to restrict data usage for unauthorised users:
I save my users in my DB too, under the same uid (and save the profile data in there). So i just set the db rules like this:
".read": "auth != null && root.child('/userdata/'+auth.uid+'/userRole').exists()",
".write": "auth != null && root.child('/userdata/'+auth.uid+'/userRole').exists()"
This way only a previous saved user can add new users in the DB so there is no way anyone without an account can do operations on DB.
Also adding new users is posible only if the user has a special role and edit only by admin or by that user itself (something like this):
"userdata": {
"$userId": {
".write": "$userId === auth.uid || root.child('/userdata/'+auth.uid+'/userRole').val() === 'superadmin'",
...
EXPOSURE OF API KEYS ISN'T A SECURITY RISK BUT ANYONE CAN PUT YOUR CREDENTIALS ON THEIR SITE.
Open api keys leads to attacks that can use a lot resources at firebase that will definitely cost your hard money.
You can always restrict you firebase project keys to domains / IP's.
https://console.cloud.google.com/apis/credentials/key
select your project Id and key and restrict it to Your Android/iOs/web App.
It is oky to include them, and special care is required only for Firebase ML or when using Firebase Authentication
API keys for Firebase are different from typical API keys:
Unlike how API keys are typically used, API keys for Firebase services are not used to control access to backend resources; that can only be done with Firebase Security Rules. Usually, you need to fastidiously guard API keys (for example, by using a vault service or setting the keys as environment variables); however, API keys for Firebase services are ok to include in code or checked-in config files.
Although API keys for Firebase services are safe to include in code, there are a few specific cases when you should enforce limits for your API key; for example, if you're using Firebase ML or using Firebase Authentication with the email/password sign-in method. Learn more about these cases later on this page.
For more informations, check the offical docs
I am making a blog website on github pages. I got an idea to embbed comments in the end of every blog page. I understand how firebase get and gives you data.
I have tested many times with project and even using console. I am totally disagree the saying vlit is vulnerable.
Believe me there is no issue of showing your api key publically if you have followed privacy steps recommend by firebase.
Go to https://console.developers.google.com/apis
and perfrom a security steup.
You should not expose this info. in public, specially api keys.
It may lead to a privacy leak.
Before making the website public you should hide it. You can do it in 2 or more ways
Complex coding/hiding
Simply put firebase SDK codes at bottom of your website or app thus firebase automatically does all works. you don't need to put API keys anywhere
I'm using Firebase to authenticate the users on my application but, since the app is very early stage, I would like to restrict the login (or registration) to only users that have a specific code.
It looks like there's no option like this and I was wondering if there's any solution that doesn't involve a back-end.
Right now I'm using a specific code in the database that the user has to enter while logging in. If that code is not correct you can't login. The problem is the function (obviously) is executed on the front-end so a person with the right knowledge could easily modify the code and still access without token.
Is there a more robust solution?
if you truly want no back end, you can see my answer at the bottom here How to protect firebase Cloud Function HTTP endpoint to allow only Firebase authenticated users? , which involves taking advantage of the fact that every firebase project is also a Google cloud platform project and GCP allows for private functions.
however, there is an easier way: just wrap your cloud function logic with an if clause that checks for any of a number of things before actually executing the function
assuming, for instance, you're on the web platform, when someone invokes an HTTPS callable function from the front, it will be sent with data and context objects.
you could check for context.auth.email to restrict to specific users. or you could check for data.mySecretKey and since the check is occurring in your cloud function, no one could inspect your code to find the key.
I'm trying to figure out how Likeboost or LikeHero work, 'cause I believe Instagram doesn't allow you to use Like endpoint to add a like to an image and they require you to submit the app for review as they stated here:
To request access to this endpoint, please complete this form.
But these apps just ask for your username and password (Surprisingly you don't get transferred to Safari for authentication process) and then you could like an image from that particular app. How do they do that? Isn't this against the following paragraph?
The ability to POST and DELETE likes, follows and comments is restricted to applications that offer business services and not consumer facing apps.
That applications that you are mentioning are using a fake native login page in order to avoid you leave from the application (like #Matthew Antolovich said). Once they get the access_token, there are no more dificulties and they can use the API calls.
As you can see in the Authentication documentation they might be using the Client-Side (Implicit) that is less secure but it works for they purposes.
They are giving permissions only to trusty applications in order to avoid that fake applications (bot apps, fake users, ...) use some API functionalities.
If you want to use these calls, you should fulfill the form that they are giving to you once your application is finished. If you are still developing the application you have to trust the Like documentation without the capability of test if it works.
There are other ways to restrict apps to use some calls (limit of requests per day, ...) but this is how they are doing it so, we must adapt.
Like #Matthew Antolovich said in his comment, if those apps are asking you for your user and password, they can log-in using the same requests present on the web. They could (and probably are) make their own API by reverse engineering the http requests.
On a side note, I would personally never trust those kind of apps.
I know there are reports of various issues when trying to pull pictures posted by 'private' users. We are working on a project that we want to use the real-time api for. After a private user approves our account, we are able to view images posted by them through the api's as expected. In addition when searching by tag we see their images. The real-time API reports the image when we subscribe to the user endpoint. We want to subscribe to the tag api, the issue is that while everything else works with private users, for some reason when a private user posts an image with a tag for which our client has subscribed, the notification is not set. It is working fine for public users, and if we search (without real-time notification) we are able to see the image. The only thing I can think of is that for search to work we must use our access key for our account (not the posters), not our clientid, perhaps real-time needs to use the same security by accesskey rather than client id?
You are correct:
we must use our access key for our account (not the posters), not our clientid
Because the privacy permissions are per-account, if you are making authenticated API calls on behalf of the user, this will not work. In theory, if you kept your hourly API calls under the 5000 limit, you could technically proxy or cache the private photos, however, rather than looking at a complicated workaround, you're better to just adhere to the API ToU:
If your application has any cached copies of User Content that has become "private," you must remove such User Content as soon as reasonably possible.
The realtime API is a bit different than the regular API as well, in that while you may or may not receive a notification of a post (it's not the most reliable service), it does't contain any data, and you're still going out to fetch the relevant data using either your own access_token, your app client_id/secret, or an authenticated user token.
Trying to get a handle on how these things work.
If I register an API key with Twitter, Foursquare, or Facebook, and I wanted to build an app on top of them. What are the general rules for API use?
Can I save/cache data a user allows me through oAuth to my own database, or am I only allowed to use it but not keep it?
I don't know about all APIs, and you should probably read the terms of service of each API you'll use.
Saving data you'll frequently need will decrease requests you'll have to do to each API, which they will be thankful for, so it shouldn't be any problem.
However, it is possibly that they require you to erase saved data if the users revoke access to your app, etc.