Firebase Security - Read with ID - firebase

I have users who can create ids with a profile attached like so:
profiles: {
id_1:
name: Bob
id_2:
name: Jim
}
Bob and Jim can sign up and input their special id provided to them. For example, Bob creates an account, with email and password, and also enters his id to see related profile info. His profile is private to him and user that created it.
When Bob signs up, how can I setup my security rules, so that before his account is created (email & password), I can check the id exists? But also keep it private, such that only those with the id can look at the data?
Let me know if I should explain differently.

If I understand your question correctly, you want the general-public unauthenticated user (before sign-up) to be able to read the UIDs, but not any of the data inside those nodes? Unfortunately that's not possible, check out this article which includes the sentence "Firebase rules cascade in such a way that granting a read or write privilege to a parent node always grants that read/write access to all child nodes."
With that said, it isn't impossible to accomplish your end-goal... instead you would need to have an additional publicly readable table that lists all UIDs, and leave the personal data inside the secure profiles table.
As I'm sure you're aware from the Firebase docs, your database rules would then use the format:
{
"rules": {
"profiles": {
"$uid": {
".read": "$uid === auth.uid",
".write": "$uid === auth.uid"
}
},
"otherTable": {
".read": true
}
}
}

Related

Firebase rules warning - any user can read your entire database [duplicate]

I recently received an email from firebase telling me that my realtime database has insecure rules. These are the rules that I have set:
{
"rules": {
".read": "auth != null",
".write": "auth != null"
}
}
Is this not a secure rule?
Email/Password is the only sign-in method that I have enabled.
firebaser here
I'm sorry if the email wasn't very explicit about what isn't secure about those rules. Securing your user's data is a crucial step for any app that you make available, so I'll try to explain a bit more about how that works below.
The (default) rules you have allow anyone who is signed in to your back-end full read/write access to the entire database. This is only a very basic layer of security.
On the one hand this is more secure than just granting everyone access to your database, at least they have to be signed in.
On the other hand, if you enable any auth provider in Firebase Authentication, anyone can sign in to your back-end, even without using your app. Depending on the provider, this can be as easy as running a bit of JavaScript in your browser's developer console. And once they are signed in, they can read and write anything in your database. This means they can delete all data with a simple command like firebase.database().ref().delete().
To make the data access more secure, you'll want to more tightly control what each signed-in user can do. For example, say that you keep a profile with information about each user under /users. You might want to allow all users to access these profiles, but you definitely want users to only be allowed to modify their own data. You can secure this with these rules:
{
"rules": {
"users": {
".read": true,
"$user_id": {
// grants write access to the owner of this user account
// whose uid must exactly match the key ($user_id)
".write": "$user_id === auth.uid"
}
}
}
}
With these rules, everyone (even non-authenticated users) can read all profiles. But each profile can only be modified by the user whose profile it is. For more on this, see the Firebase documentation on securing user data.
In addition to ensuring that all access to data is authorized, you'll also want to ensure that all data stored is valid to whatever rules you have for you app. For example, say that you want to store two properties for a user: their name, and their age (just for the sake of the example, in reality you'd probably store their date-of-birth instead). So you could store this as something like:
"users": {
"uidOfPuf": {
"name": "Frank van Puffelen",
"age": 48
}
}
To ensure only this data can be written, you can use this rules:
{
"rules": {
"users": {
".read": true,
"$user_id": {
".write": "$user_id === auth.uid",
".validate": "data.hasChildren('name', 'age')",
"name": {
".validate": "data.isString()",
},
"age: {
".validate": "data.isNumber()",
},
"$other: {
".validate": false
}
}
}
}
}
These rules ensure that each user profile has a name and age property with a string and numeric value respectively. If someone tries to write any additional properties, the write is rejected.
Above is a quick primer on how to think about securing your (user's) data. I recommend that you check out the Firebase security documentation (and the embedded video) for more.
Update: since May 2021 you can also use Firebase App Check to restrict access to calls just coming from your web site or app. This is another, quick way to reduce the abuse of your database. This approach is not foolproof though, so you'll want to combine App Check for broad protected, with the security rules for fine-grained control.
You can also mute alerts by visiting the link at the bottom of the email.
https://console.firebase.google.com/subscriptions/project/<YOUR_PROJECT_NAME>
I changed rules
{
"rules": {
"users": {
".read": true,
"$user_id": {
// grants write access to the owner of this user account
// whose uid must exactly match the key ($user_id)
".write": "$user_id === auth.uid"
}
}
}
}
But after that page not working.

Do my Firebase rules expose each users private information?

The user needs to be able to load a list of the other users, which is why I have set the "read" to true. They should only be able to write within their own folder.
My question is, does this expose all of the users information to eachother? If a user has sensitive in one of their folders information, can this be stolen?
{
"rules": {
"users": {
".read": true,
"$userId": {
".write": "$userId === auth.uid"
}
}
}
}
As you said, the ".read": true will give every user access to all the users data, since this rule is saying that we can read everything from the users node in your database.
Your rule only allows the current logged in user to write on its own node, but others users can't.

Firebase Auth with Firestore [duplicate]

I recently received an email from firebase telling me that my realtime database has insecure rules. These are the rules that I have set:
{
"rules": {
".read": "auth != null",
".write": "auth != null"
}
}
Is this not a secure rule?
Email/Password is the only sign-in method that I have enabled.
firebaser here
I'm sorry if the email wasn't very explicit about what isn't secure about those rules. Securing your user's data is a crucial step for any app that you make available, so I'll try to explain a bit more about how that works below.
The (default) rules you have allow anyone who is signed in to your back-end full read/write access to the entire database. This is only a very basic layer of security.
On the one hand this is more secure than just granting everyone access to your database, at least they have to be signed in.
On the other hand, if you enable any auth provider in Firebase Authentication, anyone can sign in to your back-end, even without using your app. Depending on the provider, this can be as easy as running a bit of JavaScript in your browser's developer console. And once they are signed in, they can read and write anything in your database. This means they can delete all data with a simple command like firebase.database().ref().delete().
To make the data access more secure, you'll want to more tightly control what each signed-in user can do. For example, say that you keep a profile with information about each user under /users. You might want to allow all users to access these profiles, but you definitely want users to only be allowed to modify their own data. You can secure this with these rules:
{
"rules": {
"users": {
".read": true,
"$user_id": {
// grants write access to the owner of this user account
// whose uid must exactly match the key ($user_id)
".write": "$user_id === auth.uid"
}
}
}
}
With these rules, everyone (even non-authenticated users) can read all profiles. But each profile can only be modified by the user whose profile it is. For more on this, see the Firebase documentation on securing user data.
In addition to ensuring that all access to data is authorized, you'll also want to ensure that all data stored is valid to whatever rules you have for you app. For example, say that you want to store two properties for a user: their name, and their age (just for the sake of the example, in reality you'd probably store their date-of-birth instead). So you could store this as something like:
"users": {
"uidOfPuf": {
"name": "Frank van Puffelen",
"age": 48
}
}
To ensure only this data can be written, you can use this rules:
{
"rules": {
"users": {
".read": true,
"$user_id": {
".write": "$user_id === auth.uid",
".validate": "data.hasChildren('name', 'age')",
"name": {
".validate": "data.isString()",
},
"age: {
".validate": "data.isNumber()",
},
"$other: {
".validate": false
}
}
}
}
}
These rules ensure that each user profile has a name and age property with a string and numeric value respectively. If someone tries to write any additional properties, the write is rejected.
Above is a quick primer on how to think about securing your (user's) data. I recommend that you check out the Firebase security documentation (and the embedded video) for more.
Update: since May 2021 you can also use Firebase App Check to restrict access to calls just coming from your web site or app. This is another, quick way to reduce the abuse of your database. This approach is not foolproof though, so you'll want to combine App Check for broad protected, with the security rules for fine-grained control.
You can also mute alerts by visiting the link at the bottom of the email.
https://console.firebase.google.com/subscriptions/project/<YOUR_PROJECT_NAME>
I changed rules
{
"rules": {
"users": {
".read": true,
"$user_id": {
// grants write access to the owner of this user account
// whose uid must exactly match the key ($user_id)
".write": "$user_id === auth.uid"
}
}
}
}
But after that page not working.

Firebase email saying my realtime database has insecure rules

I recently received an email from firebase telling me that my realtime database has insecure rules. These are the rules that I have set:
{
"rules": {
".read": "auth != null",
".write": "auth != null"
}
}
Is this not a secure rule?
Email/Password is the only sign-in method that I have enabled.
firebaser here
I'm sorry if the email wasn't very explicit about what isn't secure about those rules. Securing your user's data is a crucial step for any app that you make available, so I'll try to explain a bit more about how that works below.
The (default) rules you have allow anyone who is signed in to your back-end full read/write access to the entire database. This is only a very basic layer of security.
On the one hand this is more secure than just granting everyone access to your database, at least they have to be signed in.
On the other hand, if you enable any auth provider in Firebase Authentication, anyone can sign in to your back-end, even without using your app. Depending on the provider, this can be as easy as running a bit of JavaScript in your browser's developer console. And once they are signed in, they can read and write anything in your database. This means they can delete all data with a simple command like firebase.database().ref().delete().
To make the data access more secure, you'll want to more tightly control what each signed-in user can do. For example, say that you keep a profile with information about each user under /users. You might want to allow all users to access these profiles, but you definitely want users to only be allowed to modify their own data. You can secure this with these rules:
{
"rules": {
"users": {
".read": true,
"$user_id": {
// grants write access to the owner of this user account
// whose uid must exactly match the key ($user_id)
".write": "$user_id === auth.uid"
}
}
}
}
With these rules, everyone (even non-authenticated users) can read all profiles. But each profile can only be modified by the user whose profile it is. For more on this, see the Firebase documentation on securing user data.
In addition to ensuring that all access to data is authorized, you'll also want to ensure that all data stored is valid to whatever rules you have for you app. For example, say that you want to store two properties for a user: their name, and their age (just for the sake of the example, in reality you'd probably store their date-of-birth instead). So you could store this as something like:
"users": {
"uidOfPuf": {
"name": "Frank van Puffelen",
"age": 48
}
}
To ensure only this data can be written, you can use this rules:
{
"rules": {
"users": {
".read": true,
"$user_id": {
".write": "$user_id === auth.uid",
".validate": "data.hasChildren('name', 'age')",
"name": {
".validate": "data.isString()",
},
"age: {
".validate": "data.isNumber()",
},
"$other: {
".validate": false
}
}
}
}
}
These rules ensure that each user profile has a name and age property with a string and numeric value respectively. If someone tries to write any additional properties, the write is rejected.
Above is a quick primer on how to think about securing your (user's) data. I recommend that you check out the Firebase security documentation (and the embedded video) for more.
Update: since May 2021 you can also use Firebase App Check to restrict access to calls just coming from your web site or app. This is another, quick way to reduce the abuse of your database. This approach is not foolproof though, so you'll want to combine App Check for broad protected, with the security rules for fine-grained control.
You can also mute alerts by visiting the link at the bottom of the email.
https://console.firebase.google.com/subscriptions/project/<YOUR_PROJECT_NAME>
I changed rules
{
"rules": {
"users": {
".read": true,
"$user_id": {
// grants write access to the owner of this user account
// whose uid must exactly match the key ($user_id)
".write": "$user_id === auth.uid"
}
}
}
}
But after that page not working.

Firebase authentication - get data from other user's node but rules are set to ".read": "$uid === auth.uid"

Sorry if the title was confusing, I'll do a better job explaining here.
I was reading up on the Firebase security documentation and came across this page: https://firebase.google.com/docs/database/security/quickstart?authuser=0. Specifically I was looking at the "Sample Rules" -> "User" section which contained the following code:
// These rules grant access to a node matching the authenticated
// user's ID from the Firebase auth token
{
"rules": {
"users": {
"$uid": {
".read": "$uid === auth.uid",
".write": "$uid === auth.uid"
}
}
}
}
Assuming I understand this correctly, you will only be able to read YOUR data under the "users" node, and nobody else's.
So in my app I need to retrieve some data about a "friend" (friend count, username, posts they've made, etc) which is stored under my "friend's" user id in the "users" node. So it looks like this:
{
"users": {
"friend_uid": {
"friend_count": 10,
"username": "john",
"posts": [
"message": "post1"
],
"age": 18,
...
}
}
}
How can I do this based on the permissions above? If this is such a common task (getting some basic information about your friend), then why do a lot of tutorials show that you should set the rules to what I pasted above?
How do developers get the data they need? Do they have 2 nodes, "users" and "private_users", where in "users" they store all of the public information for retrieval from anyone, and "private_users" is where they store all the private info about the user and set stricter read/write rules?
Or do they set database rules on the individual attributes like age, name, etc?
You've basically given the answer yourself... You could either separate the data nodes and add an object with public data and one with private data, where both would have different rules for access.
For the public data node of a user, you of course wouldn't set the rules to allow complete public access when reading, but also limit it to users that are in the friend list.
Another option is to set rules on the individual properties, but this makes the rules quite big and harder to maintain, as every additional parameter needs to be added to the rules manually.
An additional thing I see when looking at your data is the missing data denormalisation. Each user object contains a list of messages/posts done by that user. So if you query a user in users/UID, you'd fetch the whole object including the possibly millions of posts/messages. So you should definitely exclude those from the user objects.

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