Our new site, example.pro, uses Firebase authentication. A small subset of our old example.com users will pay to subscribe to the new site but most will continue to use the old site anonymously.
Firebase Auth makes it easy to remain logged in to example.pro, but these privileged users might visit the old site for various reasons, including by mistake, and from different devices. So for these users I would like to detect whether they are logged in and redirect them as transparently as possible offer them a link to the new site that they can ignore and continue to use the old site, if they wish.
I have considered placing an iframe from example.pro on example.com that would trigger a dialog. Would that be safe?
Do you have a better idea?
[I've edited my question to clarify that the old site does not use any authentication or means of identifying the user, and to clarify that I want users to be able to choose to remain on the old site]
Firebase Authentication does not support multi domain authentication or something like SSO. The best you can do you implement JWT based custom auth that primarily relies on Firebase Auth. I've done that in a couple of ways and the auth flow mentioned below works best for me:
Select a domain for Firebase auth (this will be the domain where users will be logged in via Firebase directly)
When user visits one of your subdomain, let's say app.domain.com for this example, you check if there is any token present in the localStorage of browser (or any local storage of the respective platform). If yes, that means they are logged in. (I'll come back to the token later)
If the user ain't logged in on the subdomain, go to the domain where Firebase Auth works, make a call your server with the Firebase IdToken, verify that and generate a temporary token and return it. Make sure you store it in your database on server side. After that, redirect user back to the subdomain where they were trying to log in with the new token in query param. For example, your URL may look like: https://app.domain.com/login?temp_token=thatTempTokenGeneratedOnServerSide1234.
Make another request containing that temp token to your server from the subdomain and validate it (like check the UID and if it is expired and maybe if the IP of user is same when the token was created).
Generate another JWT (preferably one with long life) (You might want to look at Rolling Token Auth for better security) and return it to the client and store it on client. This JWT ideally would contain only the UID of that user. So whenever the user makes any subsequent requests to the server from that subdomain, add that token in request header (or keep it in cookies as per your convenience) then verify it on server side for processing the data.
If the token is expired, repeat the auth flow.
I've been using this for a while and found no issues. Just make sure you read about the access tokens and refresh tokens about how that works. I'll try to add a flowchart asap meanwhile feel free to ask any questions.
Related
I'm currently developing a web app using firebase authentication to make sure only authorized users can access the backend (e.g. firestore).
However, I don't really care about differentiating users but just want a single password based login/authentication. Meaning users come to the site, enter the password they know and then they get access to the protected data (e.g. from firestore). No need to create a own account.
However, I don't think firebase auth supports something like that.
What would likely work is just using .htaccess to protect the page and then provide users with anonymous accounts once they can access the app/page.
However, the browser popup caused by this is not nice enough for my purpose, I would prefer a nicely styled password form in the actual browser window.
What I could try is creating one account and sharing the password for that with all users (and set the email in the background). However, I'm not sure whether this works fine (e.g. multiple users being logged in at the same time on the same account).
Am I missing a simple option to implement such a single password based login shared between users?
Or is it e.g. possible to send a password to cloud functions, check it there and return an access token for an anonymous account from there to the user?
You can just create a single Firebase Auth email/password account and share the credentials with everyone. As long as you trust that each user will not share them with anyone else, and you trust that they will not maliciously overwrite each others' data, it should be fine.
There is an app that wants to authenticate with my users using oAuth2.
So they open a window, with the authorize URL, and parameters (such as redirect uri)
Like: https://my-website.com/api/authLauncherauthorize?redirect=SOME_URI
Now I have my own firebase-login, and when the user logs in, I get their access token from firebase. Which is what I want to respond with.
However, in oAuth2 guides/explanations like https://aaronparecki.com/oauth-2-simplified/ I see I am supposed to return an authorization code, and I don't understand where can I get that from?
What I can do, is generate a bullshit code, pair it in the DB to the access token, and then in the "token" request, send the correct access token. Is that what I am supposed to do?
Just to be clear, this is my first time writing an oAuth2 service myself.
OAuth is a system that provides authenticated access to resources. This resource can be for example a user page or editing rights to that user page. So your goal is to provide access to permissions to the right people.
When someone logs in, they get a token. Your part is to generate that token however you want, may it be some form of userdata into base64 or completely random. Take this token and link it against permissions, like viewing a page, editing it or even simpler things like viewing the email of a user.
OAuth2 tokens and/or permissions should be revokable without deleting a user. You should not use OAuth2 to identify someone.
If I am understanding your question correctly:
User visits some website
User wants to register or login using your websites OAuth2
You redirect back to the original page and send your generated token
The page can access content on your site with this token
Assuming you are the Host Site, given a User who wants to connect a 3rd party application, then the flow would be like this:
User lands on site - Clicks Login with Github
User is redirected to Github site where they login and click "Authorize"
Github redirects user back to your site /authorize with an auth token.
Your site then passes that token back to the 3rd party API (github in this case) in exchange for an access token and refresh token.
You can then pass that Authorization token to an API endpoint to get details about it. If the token expires, you can use the refresh token to get a new Auth token. Both Tokens should be stored in your database for your user.
However writing that all out I realize you are asking how do you generate the Authorization token, so I'm guessing you're actually the 3rd party API in this example. So you would want to generate an Authorization token using a random generator. Since you are using firebase, you'll probably wanna try out their token generator: https://github.com/firebase/firebase-token-generator-node
There's also some more up-to-date info here I believe: https://firebase.google.com/docs/auth/admin/#create_a_custom_token
And like you said, you would store that in a database associated with the user, and then when the Host Site sends that user's auth token to your server, you exchange it for the Authorization token (and refresh token if requested).
It's also worth reading through how google does it, because you'd be doing something similar: https://developers.google.com/identity/protocols/OAuth2UserAgent#validatetoken
JWT is another option of generating tokens: https://jwt.io/
I am currently building one web application, and I consider to use Firebase auth and its database. My concern is that if user id is on browser, does it make any security issue?
For example, say that my user id is 12345, and I would like to show some information about user 12345 on a certain page. In order to move to the certain page that I can see user's information, I click some element (like a button), and go to the page. (Ex: https://localhost:9876 => https://localhost:9876/12345) In this case, the user id is visible, but I am not sure if this is reliable approach.
Thanks.
EDIT: I just noticed that security rules should be used thanks to Eric's comment. However, I am not 100% sure if the rule can be used for auth object too. For example, auth object is used to get user id, but using user id, is it possible for someone to obtain the user's email address which is stored in auth object? For instance, in the above example, someone might obtain user 12345's email address using user id, 12345.
The correct way to secure user related resources is via a Firebase ID token. Database/Storage rules already rely on this mechanism. You cannot just rely on the correct user ID being provided. That provides no security. Instead, before return restricted resources, you should check verify the ID token and trust only its content which includes the UID. FYI: the Firebase Admin SDKs already provide an API to verify an ID token.
Typically the way to pass the ID token (if you are not using real-time database), is as follows:
Single page app: you can call getIdToken() and then pass the latest ID token in the URL query parameter, post body or the header as you send an XHR request to your server.
Traditional website: you have to set a session cookie. The easiest way is to set the ID token as session cookie and keep updating it on expiration. On your backend, you will verify this before returning the user specific resource.
I'm building an installed application that will have features requiring the Google Drive REST API using Qt and C++. I understand Qt is now releasing new libraries to support OAuth flows but let's assume I'm a student and learning to use OAuth at this layer is a requirement for this project.
In my application, I have a working OAuth flow for installed applications that ends with an Access Token and Refresh Token being stored using QSettings (I'm open to input on whether this is a disastrously bad idea too). The application requires no authentication/login for its own sake/data, but it does need authentication to Google for calling API's using an Access Token. This application has no associated web backend being hosted; its simple and should be deployable completely locally (I've written and included a simple TCP server that will receive the authorization redirect_uri and will run and close when called from within the application).
As such, I'm curious about the best way to make sure that, when a user opens my application and wants to use the Google Drive features, they are appropriately authenticated on Google's end. Say, if I maintain an access token in the registry, and this access token is granted per-user/per-application basis (right?), then how can I make sure only the user the token belongs to is able to make calls to the API with it?
Here's my understanding and approach; feel free to correct me or educate me if I've got the wrong interpretation.
If an Access Token is found, perform the following:
Open a browser page to a Google login domain and have the user authenticate there (this could prohibit a user from being able to use a cached login session that would have access to a token they otherwise shouldn't have access to)
If user has correctly authenticated with a Google account, return control to the application and make a test call to an API using the stored token.
If the call fails (responds with an invalid_credentials) I should be able to be sure its because the access token has expired and the application will go through the flow to renew an Access Token from a Refresh Token.
If no Access Token is initially found:
Start a normal OAuth installed application flow
Get the tokens and store them so that when the user opens the application next time the former procedure is used
My issue then is the first two steps if the Access Token is found. Nominally this could be done by the typical OAuth flow but it appears that when using a localhost as the redirect uri, Google will always prompt for consent, regardless of settings for prompt and access_type authorization query parameters.
What can be done to accomplish these first two steps in a way that my application can control (i.e. not a solution that relies on a backend server being hosted somewhere)?
If this question is too open-ended for SO requirements I can make some more restrictions/assumptions to limit the problem domain but I'd rather not do that yet in case I unknowingly rope off a good viable solution.
Thanks for reading! Sorry if its a verbose; I wanted to ensure my problem domain was fully fleshed out!
If you are using an installed application, I wouldn't recommend using or storing refresh tokens. Storing refresh tokens on the client side means that if an intruder gains access to the client's application, they have infinite access to the user's application without ever having to enter the user's credentials. If you do insist on having a refresh token, ensure you follow the Google's installed app flow, with the code_verifier parameter included in your requests.
If the access token is found, you should try to verify it, and if verified then use it at the google api, otherwise force the user to login again (or refresh it if you chose to still use refresh tokens).
If no access token is found, your flow sounds fine.
A few notes on loggin in with Google:
Google will only return a refresh token if you specify access_type=offline in your auth request.
Google will only return a refresh token on the user's first authorization request, unless you always specify prompt=consent in your query params.
In my experience, when leaving out the prompt query param, the user is not prompted for their consent again. If they are logged in to google, you will get a new access token, but no refresh token, unless you have prompt=consent.
I think the idea is you use prompt=consent if you have no record of the user ever using your application. Otherwise if they have used it before, you may prefer to use prompt=select_account to allow the user to select which account he wants to use in case he has more then one, or you can just use prompt=none.
This is just my understanding of it all.
My approach I ended up using was just to deploy with an SQLite db that will be stored in the AppData roaming directory. The db schema includes a field for the user's Name (from the OpenID IDToken field if it exists), the user's picture URL (again from IDToken if it exists), the refresh and access token strings (will be stored as encrypted strings when I get around to it), the user's UID/sub string, and a field for a user name and password.
These latter two fields are authentication fields for within my own application, which, again, I wanted to avoid but it seems impossible to do so. So the user will be prompted to enter a username and password into a form, and these credentials will be checked against the existing SQLite db file mentioned previously.
If they exist and are correct, the user gets logged in and will have access to their respective access and refresh token.
If the user has forgotten their password, they'll be asked for reconsent (going through the installed app flow again), and whatever password they provided during initial login will be used as the reset password. It is considered, for my purposes, that logging into Google for the installed app flow is proof enough that the user account belongs to them and they should have authorization to reset the password.
If the user is a new user and doesn't have a record in the local SQLite db file, then they can also click a button to "Create New Account" - which effectively goes through the authorization flow as well but this time a whole new record is posted to the SQLite db with the appropriate fields filled.
There's still more optimization that could be done but at least I am getting closer to the level of security and control of access to Google user accounts that I want.
I'm not marking this as an answer because I feel like this solution is still not desired and that there should be an easier way. So if someone has evidence or experience of providing an equivalent level of authentication control without needing to maintain a local user account database then I would be more than happy to mark such a method as the solution!
Thanks again!
I have an existing Wordpress site. The plan is to rebuild the site using the cakePHP framework. Due to time restrictions, I want to replace individual sections of the Wordpress site one at a time. This will mean that both apps will be running side by side for a certain period of time. I need to control access to the cakePHP app using the authorization provided by Wordpress. I'm not sure the best way to go about doing this. I've seen similar questions asked a lot, but I have not yet found a clear solution.
I'm thinking about two approaches:
Plan A:
Configure Cake to look for Wordpress's authorization cookies.
configure Cake to look at Wordpress's database.
Borrow some of Wordpress's authorization logic to teach Cake's Auth component how to authenticate WP users.
Plan B:
set up an authorization API on my Wordpress site.
set up separate auth component in cake.
ping the WP endpoint when a user hits a protected page in the cake app and then manually log in the user. (This would create a second set of auth cookies)
Do either of these sound like the right approach? Is there a better way to do this?
Helpful references: Article about Cake session handling, Cake Auth component documentation, Cake Auth tutorial, brief overview of WP authorization, a more in depth look at wordpress authorization
UPDATE
We've started working on this, and it seems like it will work, but there is a very tricky aspect involving password hashing that warrants its own question. If you're following this thread, you may want to have a look.
I once had a similar situation: Cross framework authentication zend + codeigniter which was few months ago...
Anyways, this is what I will prefer:
set up an authorization API on my Wordpress site.
set up separate auth component in cake.
ping the WP endpoint when a user hits a protected page in the cake app and then manually log in the user. (This would create a second set of auth cookies)
Here, I would suggest a slight change which is do-able.
Make sure, you have a token system of SSO. As in, when person is logged in on Wordpress, set another cookie which will have a token: Token will be username + password (hashed) + secret key, which will be same between Wordpress and CakePHP. On either site, look up for cookie and manually log the user in or just perform a database look up. Hashing is important for that cookie!
However, if the site is using different domains, you might need to re-strategize:
I had different domains once. At the login or unauthorized page, I would ping the other website and bring up their login box. On the other website if the user is logged in, they get post login page and if request URI has sent a token, we perform normal operation and return the authorized token to this (current) domain.
In simple words:
Site A = WordPress & Site B = CakePHP
Site B hits a page where authorization is required then, ping Site A for a login (as it happens when u do Login-with-Facebook sort), which will request via a Token (private key) and REQUEST_URI which will be part of SSO verification table on Site A, if person is already logged in then, Site A will return (via POST) a token, which further will be decrypted via (private key) of Site B and log the user in. Private key of B and A will be same.
Hope this was understandable.
Questions? :)
Answer to your questions in comment:
Ideally, why we use SSO? We use it because of many constraints. For example: You have a database of say... a million row with more than thousand tables, you need to add a module over ur huge app already... so, instead, you will use another database... SSO will return user information, which can further be replicated. For example, when you click on 'Login with Facebook', it returns requested information, like email address, or user's name or even profile picture. Which can further be added to our database... Keeping different databases is strongly recommended :)
To your 2nd and 3rd question: Should both sites reference the same users table in the database? different databases is recommended unless, you are using the same data. Or say changing the software platform.
Should I copy the site-specific user rows into separate user tables for each app? Yes, that should happen automatically. Once you are registered on a main site, nothing happens, things should happen once you are logged in already and then go to site B... Once logged in, user info can always be requested :) That way, new site will have active users ! 2 birds?
Don't complicate (bother) yourself with how what works but, concentrate on how, what is achievable in short period. SSO - Logged in - Restricted page - Look out for log ins - Either login - If already logged in - fetch user info - If user info exists - login via secondary site OR set the new user info . Done!
We developers love flow charts! Don't we? I just created one:
Further answers:
Does the "Fetch User Info" stage mean that we take the user info from the site which is logged in, and create a new user (row) automatically in the other site?
Ideally, you will ask permission from the user before they 'allow' their info to be used but, it varies how your privacy policies are.
In other words, one site handles all the registration/user-creation and the other site just waits for that user to show up and trigger automatic creation. OR at the moment a user registers on the one site, BOTH databases get a user row inserted?
one site handles all the registration/user-creation and the other site just waits for that user to show up and trigger automatic creation. You can have both. Sign up on your website and also a trigger based automatic creation. Depends on your strategy. OR at the moment a user registers on the one site, BOTH databases get a user row inserted? That would be a horrible practice! It will kill the motive of SSO. Motive of SSO is to create an auth family which can be used by users so that they do not have to register every now and then for different websites. update only one database at a time and other when required :)
Questions? :)
I have done this once. I don't have the snippets and/or any references to anything. But thought it might be helpful.
Configure WP and CakePHP both to use same session, you can do this by session id and session name,
When User registers for your website, register them using both WP and CakePHP,
Choose one framework that will handle login view from the front end. I had chosen CakePHP as I was more proficient with it, once the login is successful locate the same user in other framework's DB and authenticate the user using their authentication system.
Hope this helps !!!
Suggestions:
If you are building a closed system, meaning you have to be signed in to access anything useful in the site, then you can use CAS . I know it's used by mainly universities, but for closed systems it works.
( If you need to handle anonymous users the suggestions below might help)
Keep it simple and, similar to Part A of your plan, have a cookie ( visible by both cake and wordpress ) that simply states if a user is logged in. The cookie should be created/checked by both cake and WP. Cake does not need to look at WP's DB. The cookie can have information on how the users in each system are mapped.
Have a central login screen, this is similar to what CAS does. But please build your own. CAS does not handle anonymous users. I am currently creating a central login screen for work. It's simple. The central login screen will handle all authentication and create the cookie visible to both WP and cake. This would mean that the login link for WP and cake will redirect a user to a common page. The link will need to provide a callback URL so that after the user authenticates successfully, he is redirected back to the original service. You will need to decide on a central DB for user authentication.
The cookie approach has following bonus:
It's a lightweight solution and can be wrapped with an on/off switch. In WP, simply wrap the cookie logic with a wp_options value.
You can use WP's and cake's authentication system. no need to work with API's and/or sessions. No need to couple applications by looking at each other's DB.
You can keep roles and permissions native, meaning WP will work with it's own roles and permissions system and your cake application will work with it's system.
Adding a new "service" to your platform is as simple as "create/check for a cookie" then use the system out-of-the-box auth system to log the user in.
Single Sign On is as simple as creating a cookie. Single Sign Off would be deleting the cookie.
I can definitely go into more detail on each suggestion if you're interested.