I am using Firebase's email + password Auth system.
I have a use case(passwordless auth) where I'd like to verify the user's email a second time.
So assuming they already had their email verified once, I'd like to:
Send them another "verify your email" Email, i think this would work by simply calling sendEmailVerificationWithCompletion(..)
After they verify their email a second time, Determine that they did. The first time I can check the emailVerified Boolean, but is there a way to reset this emailVerified Boolean to False and check it a second time?
How can I achieve this?
[Edited]
More description if it helps:
Im trying to do Passwordless Authentication. Maybe this is not possible on Firebase and I'd have to use something like auth0
I have only 2 flows.
Flow 1: Sign Up
Input an email and username (Display name in firebase).
Verify your email.
Now you stay signed in until the app is deleted from the phone ( a default password is used to sign you in and sign you out on app open and app exit respectively)
Flow 2: Login
This flow becomes relevant if you have an account with the App, but you deleted it in the past and reinstalled again
Input your email/username
if you have an account, you'll get an email to "verify that it is you again"
Verified? Now you stay signed in until the app is deleted from the phone ( a default password is used to sign you in and sign you out on app open and app exit respectively)
I dont think a true passwordless email-auth system is possible in Firebase. Im going to instead do this with Auth0
Related
I am developing Android app using Firebase. Because of that, I want to use Firebase Auth. I have following requirements:
Register/Log in using Facebook
Register/Log in using Email/Password
Register/Log in using Phone Number/Password
The first two are OK, I followed basic tutorials. However, Phone Number / Password is the problem here. Firebase supports only Phone Number/SMS Token for this (its called Phone Auth), but there is no mention about my case. I do not want to hack Firebase and use its realtime database instead of Auth 'database'. Is there any better way to achieve this?
Thank you.
If you have both email and phone of your user and you can use Admin SDK, then perhaps you could exchange users phone number to his email and login with email and password in the background.
Something like this (node.js)
admin.auth().getUserByPhoneNumber(phoneNumber)
.then(user => {
firebase.auth().signInWithEmailAndPassword(user.email, password);
});
Firebase phone authentication is using OTP(one time password). This way there is no hassle for the user to remember the password. Once authenticated, you will be registered. The sms code acts as a password. But that is for one time. Usually , users prefer such behaviour in which you dont have to remember the passwords. If you are still looking for the way you want, see this link and create a custom authentication method.
https://firebase.google.com/docs/auth/android/custom-auth
I had a similar problem -
I combined firebase auth(email + password) with (phone+otp) to get phone+password auth -
https://medium.com/#shivampesitbng/firebase-phone-password-auth-in-vue-b94f15b8fb3d
Use Fake Email:
Well, Firebase doesn't support sign in with mobile number and password but it supports email and password. So you can create a fake email with your mobile number.
Ie: 78******69#yourdomain.com
Also, you can create a complete Authentication system using it.
Registration:
Input user mobile and password and proceed to the next page.
Now use Firebase Phone Auth (OTP) to createUser. If process success, link fake email, password credentials in background.
AuthCredential credential = EmailAuthProvider.getCredential(email, password);
auth.getCurrentUser().linkWithCredential(credential);
Login:
Input mobile and password to login. Convert the mobile in fake email and then signInWithEmailAndPassword().
Forget Password:
Redirect the user to a new Page and user Phone Auth to verify the user. If successful, input a new password and change the password of the Email Auth.
At the first time, while signup with Gmail and password, firebase saved the credentials correctly. But the next time, I Login with Firebase Google authentication with the same Gmail which i gave while signup, the credentials are overriding in firebase account. After overriding the credentials, we are not able to login using that signup credentials. Can anyone explain how to achieve this?
What happened
In the first screenshot you signed in with the email+password provider of Firebase. While this is a valid sign-in method, it means that anyone could've entered that email address, even if they don't actually have access to the Google account for that gmail address.
There is no security risk here, but the level of trust we can put in the value of email address is low. For this reason the emailVerified property of the account is marked as false and you'll typically want to require that the user verify their email address before allowing them to continue.
In the second screenshot, the user signed in with the same email address, but now with the google.com provider of Firebase. This means that Google now verified already that the user has access to the underlying gmail address of the account. Since the google.com provider is the trusted provider for #gmail.com accounts, the system replaces the previous account.
Also see:
Authentication using Facebook at first and then Google causes an error in Firebase for Android
Firebase Overwrites Signin with Google Account
Trying to understand Firebase Authentication one account per email address and trusted providers
What you can do
You'll typically want to prevent multiple users from signing up with the same email address. For this, you'll want to configure Firebase to only allow a single account per email address in the console, and then use account linking so that the two (email+password and google.com) accounts in your scenario are merged.
Did you verify the email or phone number from the first login attempt? If not, this is by design:
After sign-in completion, any previous unverified mechanism of sign-in will be removed from the user and any existing sessions will be invalidated. For example, if someone previously created an unverified account with the same email and password, the user’s password will be removed to prevent the impersonator who claimed ownership and created that unverified account from signing in again with the unverified email and password.
Source
I just ran into this problem and here is a longer and more in depth description. (Things change often, this was true in Nov 2021.)
SHORT VERSION: As #Frank van Puffelen said, this is by design. The issue is that email+password is not a trusted provider usually, so a trusted provider like Google Authentication overwrites that method. It does this silently (I think, didn't check every field in GoogleSignInAuthentication object.)
It does auto-link after a password reset OR the email is verified via a link. See https://firebase.flutter.dev/docs/auth/usage/#verifying-a-users-email on code to do that.
Also: I don't recommend turning off One account per email address as some others suggests . See the reason for that at the end.
"Weird" Behavior under default One account per email address
In my app, the following happens.
SignUp via email+password for testUser1234#gmail.com.
creates an account for c_example_account#gmail.com with provider=Email/Password as indicated by the envelope/mail icon in the firebaseAuth dashboard.
LogOut and re-signin via Google Sign In for c_example_account#gmail.com
The provider is changed. Old provider is Email/Password icon (envelope). New provider is Google icon. (like the bottom three accounts in the screenshot). Note also that the User UID is the same. So anything anything linked to that User UID is still okay.
Since the Email/Password login method (AKA) provider was removed for c_example_account#gmail.com, the user can't login with that method anymore. IMPORTANTLY: This is done silently without the user getting any notification that the Email/Password login was removed.
Trying to sign on using Email/Password will result in an error Incorrect Password. Note: one might expect it to give an error like "Only Google Sign-In is available", but it doesn't. Contrast this to when the email doesn't exist (like trying garbage#123457.com), which has an error Email is not found...
Now, it gets a little weirder...
Suppose the user uses "Reset Password" like being called like this
Future<void> resetPassword(String email) async {
await _firebaseAuth.sendPasswordResetEmail(email: email);
}
Then, the firebaseAuth console has TWO methods for the same USER UID. See the second and third line in the screenshot.
Now, both methods are allowed. The difference is that the first time was a createUserWithEmailAndPassword() like
await _firebaseAuth.createUserWithEmailAndPassword(
email: email,
password: password,
);
...but this time it was created via a "Reset" event
Future<void> resetPassword(String email) async {
await _firebaseAuth.sendPasswordResetEmail(email: email);
}
... that gave a link via email sent by firebaseAuth service. In this case, the email was verified.
Recap: Now both methods work. The two methods being (1) Google authentication and (2) Email/Password. In Google parlance, the accounts have been linked: https://firebase.google.com/docs/auth/android/account-linking. Linking means One User UID, multiple login methods
Why the funky behavior when Email/Password is created in two different methods?
~~I couldn't find this documented in firebaseAuth, maybe because I didn't look hard enough or maybe because it's not a common issue. ~~
UPDATE: This behavior is documented in an issue comment from April 2020.
I think the reason is because the _firebaseAuth.createUserWithEmailAndPassword version has an unverified email. So, anyone can create an account for anyone else assuming that the email+password combination doesn't exist. For example, I could create an account with username president#whitehouse.gov without actually having access to that email. If the actual president logged in via Google Authentication, then I'd have bogus access to that user's info. Except that the clever google engineers decided that the verified Google Authentication then triggers the deletion of the unverified Email/Password provider/account instance.
In short, the logic might be: verified trumps/overrides unverified. See https://firebase.google.com/docs/auth/users#verified_email_addresses
Again, none of this is documented explicitly for Email/Password. But it is hinted at in the documentation, like if a Facebook Auth account gets over-written by a Google Auth.
Snapshot of the Verified Email details
Copied from: https://firebase.google.com/docs/auth/users#verified_email_addresses
Bolded added by me, for emphasis
In some situations, Firebase will automatically link accounts when a
user signs in with different providers using the same email address.
This can only happen when specific criteria are met, however. To
understand why, consider the following situation: a user signs in
using Google with a #gmail.com account and a malicious actor creates
an account using the same #gmail.com address, but signing in via
Facebook. If these two accounts were automatically linked, the
malicious actor would gain access to the user's account.
The following cases describe when we automatically link accounts and
when we throw an error requiring user or developer action:
User signs in with an untrusted provider, then signs in with another untrusted provider with the same email (for example, Facebook followed
by GitHub). This throws an error requiring account linking.
User signs in with a trusted provider, then signs in with untrusted provider with the same email (for example, Google followed by
Facebook). This throws an error requiring account linking.
User signs in with an untrusted provider, then signs in with a trusted provider with the same email (for example, Facebook followed
by Google). The trusted provider overwrites the untrusted provider.
If the user attempts to sign in again with Facebook, it will cause an
error requiring account linking.
User signs in with a trusted provider, then signs in with a different trusted provider with the same email (for example, Apple
followed by Google). Both providers will be linked without errors.
You can manually set an email as verified by using the Admin SDK, but
we recommend only doing this if you know the user really does own the
email.
Why not turn off One account per email address
By default, the setting One account per email address is active as #Deva wrote. But, unchecking this means that there are two different accounts (User UIDs) for the same email. One via Email/Password and one via Google Authentication. They will have separate User UIDs in Firebase Auth, so that may confuse you. Furthermore, if you manually link in your app two User UIDs, this creates a security hole: Someone can create an account without email verification to get access to an existing account. So don't do that.
Related StackOverflow questions and links
https://stackoverflow.com/a/60276351/233382
why i can't link email/password to the same email exist in google sign in provider in firebase flutter?
https://github.com/firebase/firebase-ios-sdk/issues/5344#issuecomment-618518918
Background:
I am developing an IOS app using firebase as backend.
There are 3 authentication:
1:password and email
2:FaceBook
3:Google
I have checked the option "one email per account" option.
The situation is:
Say if I first sign in with one of the Auth provider and later, log out, and want to sign up with any other two Auth providers. I will get an "the email address has been used" error if the associated Email of the current provider is the same as previous. In this case I want to link the current Auth account with the previous account.
I understand that I need to call the linkWithCredential:completion: method to link the accounts. But I first need to sign In the previous account but how can I tell which account to sign in? For example, if I log in via Facebook and get the "same email being used" error, how do I know at this point whether should I sign in via Google or the email/password?
One interesting thing is If I use Facebook or email/password to sign in first and later sign in with Google, firebase will automatically handle the linking but the default behaviour is to overwrite the previous Auth provider with Google and keep the UID...
I have found an useful post How to manage users' different authentication in firebase
But it only deal with a simpler situation where authentication are only two.
When you get the credential already exists error, you already have the email at that point, you then call fetchProvidersForEmail with that email which will lookup the provider IDs associated with that email. You then sign in the user with one of those providers. After you finish sign-in with the existing account, you call linkWithCredential:completion: with the original credential that caused the error to occur. This causes the accounts to link. The next time the user tries to sign in, they will be able to sign in to the same user with either provider.
Check FirebaseUI-iOS which already takes care of the whole flow for you. You can also check there source code to see how they handle such situations: https://github.com/firebase/FirebaseUI-iOS
I'm working with AWS Cognito. I have my sign-up flow working just fine. They user fills out their email addresss and password and I create the account in the proper User Pool. I have email verification enabled, and the email is sent and is received in short order. After the Sign Up screen the user is presented with a verify screen to accept the code that was just emailed. Again, this all works great.
What I am trying to understand is:
Once I have a user signed up and verified, in order for the iOS AWS SDK to do it's thing, so I need to then tell the user to go sign in or am I just missing some call that can grab their credentials once they are verified?
My guess is, since we don't know when the user verified themselves, it could be hours later and they could have killed the app and restarted it in that time that the expected flow is to have them sign in again.
Since the app does have the password in memory (NOT stored anywhere on disk) that they used to sign up in the current signup navigation controller/flow I supposed I could just force the sign-in after the verify completes.
I just wanted to make sure I didn't miss something in the SDK or it's docs about this case.
Your understanding is correct, there is no verification flow that will skip sign-in. One option would be to keep the password they used to sign-up in memory and if they verify immediately use that. If they come back some time later or restart the app force them to sign in.
I want to add "Login with Email" functionality in ios app.
I searched about this, but i found that we can not get default email account of iPhone.
Can anybody suggest me how should i proceed for this issue. Thanx in advance.
use this link for your login with gmail http://technogerms.com/login-with-google-using-oauth-2-0-for-ios-xcode-objective-c/
will u need just like this , here i used
Login with FB
Login with Twitter
Login with manually
-- here i used server and Sqlite for save the user information
-- email, name, p/wd, phone number, etc.
-- this login accessing with our own db or server
Of all the apps that ask for email and password, none get it directly from the iPhone settings, which makes me believe that there must be some sort of restriction for gathering that information.
So, then the procedure is ask for email and password from the user directly, fire a url to validate and check for the user with those credentials and either login or ask him/her to sign up