We are building a js library which is included on third-party sites. When a user takes an action on the third-party site, our library pushes it to a write-only path on Firebase corresponding to the url they made it on.
To allow our clients to view the actions the user has taken ON their actual site, we'd like to log them into firebase on our end and then redirect them to their own site. Our library on their site checks if their uid matches for 'owner' for this site; if so, they then get read-access to the firebase path and can see these 'actions'.
I hacked something up but realise I can't persist sessions between domains. It does work when our clients login from their site, through our js drop-in. We're just using simple login right now, and don't have anything server-side. I'm using the js lib.
Can I use firebase to do this, or do you not support cross-domain sessions? I'm open to spooling up a backend if custom auth will help.
Cheers!
Related
I'm writing a client in NodeJS that is meant to replace using a website, and it isn't my website. It uses Facebook to log in. Is it possible to log in via a Facebook username/password? It seems modules like passport-facebook are intended for use with a website that you own, which is not the case in my scenario.
I suspect that I can't login with a username and password, so I'd have to sniff web traffic of me browsing the normal website for my token for the website, and then somehow use that in Node, but I hope this isn't the case.
Thanks for your help.
Firebase provides database back-end so that developers can focus on the client side code.
So if someone takes my firebase uri (for example, https://firebaseinstance.firebaseio.com) then develop on it locally.
Then, would they be able to create another app off my Firebase instance, signup and authenticate themselves to read all data of my Firebase app?
#Frank van Puffelen,
You mentioned the phishing attack. There actually is a way to secure for that.
If you login to your googleAPIs API Manager console, you have an option to lock down which HTTP referrer your app will accept request from.
visit https://console.developers.google.com/apis
Go to your firebase project
Go to credentials
Under API keys, select the Browser key associated with your firebase project (should have the same key as the API key you use to initialize your firebase app.)
Under "Accept requests from these HTTP referrers (web sites), simply add the URL of your app.
This should only allow the whitelisted domain to use your app.
This is also described here in the firebase launch-checklist here: https://firebase.google.com/support/guides/launch-checklist
Perhaps the firebase documentation could make this more visible or automatically lock down the domain by default and require users to allow access?
The fact that someone knows your URL is not a security risk.
For example: I have no problem telling you that my bank hosts its web site at bankofamerica.com and it speaks the HTTP protocol there. Unless you also know the credentials I use to access that site, knowing the URL doesn't do you any good.
To secure your data, your database should be protected with:
validation rules that ensure all data adheres to a structure that you want
authorization rules to ensure that each bit of data can only be read and modified by the authorized users
This is all covered in the Firebase documentation on Security & Rules, which I highly recommend.
With these security rules in place, the only way somebody else's app can access the data in your database is if they copy the functionality of your application, have the users sign in to their app instead of yours and sign in/read from/write to your database; essentially a phishing attack. In that case there is no security problem in the database, although it's probably time to get some authorities involved.
Update May 2021: Thanks to the new feature called Firebase App Check, it is now actually possible to limit access to your Realtime Database to only those coming from iOS, Android and Web apps that are registered in your Firebase 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.
Regarding the Auth white-listing for mobile apps, where the domain name is not applicable, Firebase has
SHA1 fingerprint for Android apps and
App Store ID and Bundle ID and Team ID (if necessary) for your iOS apps
which you will have to configure in the Firebase console.
With this protection, since validation is not just if someone has a valid API key, Auth domain, etc, but also, is it coming from our authorized apps and domain name/HTTP referrer in case of Web.
That said, we don't have to worry if these API keys and other connection params are exposed to others.
For more info, https://firebase.google.com/support/guides/launch-checklist
I want to create a web page, that will serve to authenticate users based on credentials I give them (user1, pswd1 etc).
Only after a user authenticated, he should have access to a few other web sites,
on different folders of the web server, but which have no server side code(otherwise it would be simple.)
The user should be allowed access to the other sites, e.g. based on his IP,
for 24 hours or another period, or while he has the authentication site open on his browser.
The purpose if that the user will not have to enter credentials on each site,
and will enter his credentials only once, or once a day.
Restrictions:
I don't want to modify the target web site javascript code at all, e.g. to query a web service.
The user should be granted access using any browser,
so I assume I cannot use cookies.
If I would develop such a mechanism on Apache,I could, for example, have the authentication site PHP code add a line "Allow from ip" to the htaccess file of each target web folder, whenever a user authenticated successfully.
The issue is that I don't want to develop it as I am sure a solution already exists, and also I need a similar mechanism for both Apache and node.js (although i can live with two different solutions)
What information does the user have to identify themselves? How do you guarantee the user is who they say they are?
The whole point of authentication is to establish the user is who they say they are and that may create a session so that users need not reauthenticate.
If you want the user to authenticate in a single location and then reuse that "session" or set of credentials elsewhere, what you are looking for is single-sign-on / identity federation.
For instance, take airbnb.com. I do not need to authenticate there. All I have to do is authenticate with a third-party e.g. Google or Facebook. As a matter of fact, SO works in the same way.
One of the standards behind this technique is called Open ID Connect. Look into that. If you are willing to dish out money, you can look into commercial solutions e.g. Ping Identity. There is an open source implementation provided by Mitre / the MIT. It's available here.
In fact it occurs to me I can use simple routing.
In the top level folder have php code that does the authentication.
If the user is authenticated, route/redirect to the requested target site,
based on the requested url.
The url should be for example http://mysite/site1, where the authentication code is in the folder mysite, and site1 is not directly accessible.
Perhaps I can use something like php-express to reuse the same php code on node.js.
Help me..
I'm implementing a web application in my local server and after i will publish my application to download and can use every one.So I need to give a social experience to user with my web application(user can update his fan pages through my web application). So i created a facebook application. But I'm still in problem what is site url in application. This is not for my own web site. This is for all download users. Then how can I create a facebook application to achieve this.
With a facebook Canvas App, site url is where the actual application is hosted.
So, if your web application was fully functional at http://example.com/facebook, that would be the site URL.
I created a facebook app last year and it's a web based application that is wholly contained within my webserver, the site url points to it's landing page.
I think you want to make this application downloadable like wordpress framework so that others can host the application on their server and use it.
So probably best way is to have a admin section like in wordpress, user who download and implement you application on his or her server can provide their own application access token.
Insted of hard-coding your own access code into your download application framework
In admin section create a tab to register your application with facebook, which will redirect user to the facebook.com/developer where he/she can register their application and after registration they can put their access token back in you application framework admin section. you can store this details in some table and fetch it where ever you need it for authentication.
hope this logic helps for you.
I have a main website running on AppEngine. It's on a subdomain like main.example.com. This main application is a content portal for our customers. It offers an Ajax application built on YUI. Customers can upload data to it. Users authenticate using Federated Login.
The Ajax application on it allows users to process the data previously uploaded. To do it it should use an webservice running on other subdomain like service.example.com. The webservice does not run on AppEngine but on our services - it's CPU heavy and built on other set of technologies. It would need to download the data on main application - but the downloading service - like everything on the main application - is behind the authentication wall.
I could programatically always allow the service to download wharever it wishes but I think this can turn into a major security problem.
How can I reuse the OpenID authentication "token" to allow it (the service) to appears to the main application as the authenticated user so it can download data? Or If I can do this what would be the best way to accomplish what I intend to do?
You can't really reuse the authentication token. What you should use is something akin to OAuth, though since you control both ends you can make it somewhat simpler:
Generate a shared secret, accessible by both main.example.com and service.example.com
When a user accesses service.example.com for the first time (no authentication cookie), redirect them to main.example.com/auth?continue=original_url (where original_url is the URL they attempted to access)
When you receive a request to main.example.com/auth, first log the user in the regular way (if they're not already). Then, take their user ID or other relevant credentials, and generate an HMAC from them, using the shared secret you established in step 1. Redirect the user to service.example.com/finish_auth, passing the computed HMAC, the authentication details such as user ID, and any parameters you were passed in such as the continue URL.
When you receive a request to service.example.com/finish_auth, compute the HMAC as above, and check it matches the passed in one. If it does, you know the request is a legitimate one. Set an authentication cookie on service.example.com containing any relevant details, and redirect the user back to their original URL.
This sounds complicated, but it's fairly straightforward in implementation. This is a standard way to 'pass' credentials between mutually trusting systems, and it's not unlike what a lot of SSO systems use.