I am creating a SaaS that will allow users to interact with it via their web applications. I would like to create a CAS type login mimicking Facebook connect so when you click the 'Login' button on the users website it will popup a window for you to login with my SaaS credentials.
I do not want the SaaS users site to be able to access the users login credentials so this is why I thought of CAS. However, it doesn't look like Facebook Connect redirects to the CAS server. It looks like they just popup a window to the facebook login then create a cookie once the user successfully logs into facebook. How then does the Facebook Connected site access that cookie?
I am wanting to basically be able to keep the end user on the current website without being redirected to my login application. I would like to mimic what facebook does with just popping up a little window and have them login then refresh the page after they login but I am not sure how to go about this.
Any ideas?
Facebook uses a third party cookie: they set a cookie on your domain that you can access to get the necessary credentials.
EDIT: the easiest example would be to look at PHP's setcookie function. Notice that there is a domain parameter. If you change the domain to match the domain of the actual website that initiated the authentication action then you'll be able to set a third-party cookie.
Note that on IE there are certain headers the domain that initiated the authentication action needs to set to allow your third-party cookie to be set. See http://www.spamcollect.com/archives/33 for a short writeup of how that works.
If you are working in a different language you'll need to use whatever cookie management functions they offer.
Another option may be to do this with CAS programmatically using the REST client.
https://wiki.jasig.org/display/CASUM/RESTful+API
In this way you could take the users details and login to CAS without being redirected.
Facebook uses Cross Domain communication which is what I will be using.
Related
I am very new to IdentityServer and Open ID Connect and most of what I know comes through the three walk throughs in the Overview section of the IdentityServer3 documentation. All of those samples demonstrate how to use the Authorize attribute to secure a controller action, which results in a redirect to the IdentityServer-hosted login page. What is the typical or recommended way to provide a Login link in the client application? Could my client application have it's own login page and then call IdentityServer to validate the login and provide a token? If so, is there a sample that shows this? If not, is there a way to have the login link in my application bring up the IdentityServer login page? Is it as simple as securing the Login action with an Authorize attribute?
I don't think it is right that client has its own login page. Imagine you use Facebook as identity provider, and would you expect facebook users to enter their Facebook crediential on your login page?
One method is what you described using server side challenge redirect, or configure your app as a Javascript implicit client - see example , which it builds up authroize challenge URL. Either way user sees login page from identity server.
I'm running a Classic ASP website, that has its own user authentication and login mechanism. For example, In order to remember a logged-in user, ASP creates an encrypted cookie and a 20-minute session for each connected user. If the 20 minute session is elapsed, the server revives the session from the cookie saved previously, and saves some data regarding the user to the database.
I want to to be able to allow users to connect with their Facebook or Google identity, but the mechanism used by Facebook or Google is based mainly on Javascript and on client-side code.
How Facebook or Google login can be used while maintaining server side code in ASP? (So that the ASP server can still manage the session and save data regarding it, for example whenever a session is revived)
For me somehow it seems that it may become less secure to use client-side authentication as the code may be altered easily. Isn't this the case?
If I use client-side javascript and log in with Facebook, how would I update the user data retrieved from facebook back into my database, for example the user's first and last name?
For me it sounds that it should be a "server-to-server" communication (between my ASP server and Facebook's or Google's servers) and what they propose is a "client-to-server" communication ... Any ideas how this can be done?
Any help or explanation would be very much appreciated! Thanks.
I'll try to address your Facebook-related questions one by one. However, I will not give you an implementation or any ASP-specific feedback, but only a rough approach. Additionally, I recommend that you study Facebook's documentation on Facebook Login extensively to further your understanding of the matter.
1. Facebook documents the server-side OAuth 2.0 flow in their Manually Build a Login Flow guide. Basically you redirect the user to a specific FB URL that (in the parameters) tells FB to render the "Login with Facebook" dialog, and which permission scopes to ask for. Once the user approves the Facebook Login for your webapp, they will be redirected back to your web app, e.g. with an OAuth token in the query string, that your webserver can then exchange for a user access token.
Once you obtained a user access token, you could e.g. store it in your web app user's session.
2. I don't know what you mean. Client side apps are fairly secure. Perhaps you can convince yourself about how secure JS apps are when reading about things like CORS.
3. If you only use JavaScript (e.g. Facebook's JS SDK) and you want to store e.g. app-scoped user IDs on your server, you need to expose an endpoint on your server that your JS application can submit that kind of information to.
4. You state
what they propose is a "client-to-server" communication
Who are "they", and where are the proposing this? The resources I linked to in 1. should explain how you can use Facebook login in a pure server-to-server way.
I'm writing a VC++ app and I would like to allow users to login via Facebook. Looking through the documentation, it looks like they only support php on servers, JavaScript, and native mobile clients.
Right now what I'm thinking of doing is to open a browser window in the app, have the user authenticate, and then grab the auth token to do native app calls.
The other thing I was thinking of is having the user enter the Facebook username and password into my app and then using that directly, but I'm not sure if that's allowed.
How do I authenticate a desktop app with Facebook?
Right now what I'm thinking of doing is to open a browser window in the app, have the user authenticate, and then grab the auth token to do native app calls.
Actually you are on the right track: Facebook provides you with a so called "Manual Flow".
So this is how you authenticate your users with Facebook in your app in three steps:
Step 1
When the user should login to Facebook, open the embedded browser and point to this url:
https://www.facebook.com/dialog/oauth?client_id={app-id}&display=popup&redirect_uri=https://www.facebook.com/connect/login_success.html
Three things to note here:
Of course, you need to replace {app-id} with your application's id.
The redirect_uri must be set to https://www.facebook.com/connect/login_success.html when using a desktop application (that's your case).
You can also specify additional parameters, for example if you need to request extended permissions from the user (publish_actions, etc.). See the full list of optional parameters for more information.
Step 2
Make sure you have enabled the following switches in your app's advanced settings:
For security reasons, you should enter https://www.facebook.com/connect/login_success.html under "Valid OAuth redirect URIs", but it worked for me without explicitly setting this.
Step 3
Now the redirection by the Facebook servers should navigate the browser window to the redirect uri from above. It will also include the access token in the uri's fragment as follows:
https://www.facebook.com/connect/login_success.html#access_token=ACCESS_TOKEN...
Use the ACCESS_TOKEN in order to make any subsequent calls to the Facebook API - et voilà!
I know that facebook allow me to specify multiple domains for my app.
But in the "Website with Facebook Login" i can only specify one url.
Is it possible for me, to authenticate users on domain.se, domain.dk and domain.net with the same App ? Or should i still create one app, for each domain ?
It is technically possible to use Facebook Connect on multiple domains, there are some limits (5 domains max).
So the key to doing this is adding all domains in the App Domain field under your app settings.
The PROBLEM, however, is that Facebook only lets you add domains that are derived from your Canvas URL or Site or Page tag URLs, so if you try to enter anything else you get an error that looks like this:
The SOLUTION is to create App on Facebook, Website, and Facebook Tab using the ADD PLATFORM button and then put in URLs that point to your other domains. Here is an example of what I mean:
If you use a unique domain for each field you can max out with 5 different domains. I have tested this technique with up to 3 domains, but i think it should work for all 5.
Note: Facebook admin features change from time to time, so all of this is subject to change
As long as you listed all the desired App Domains in application settings you should be able to authenticate users on any of them.
"Website with Facebook Login" is really only intended to be used as link to your site/application.
Update 2 (July 2016):
App domains must match the domain of the Secure Canvas URL, Mobile Site URL, Unity Binary URL, Site URL or Secure Page Tab URL.
Update (December 2013):
At the time of writing original answer it was possible to list any domains in application settings but from that time the UI of Application Settings (as well as way of handling Application Domains) changed at least couple of times, at some point you could only list domains that derive from one of application's canvas pages.
As of December 2013 it is possible (again) to list domains that do not derive from application canvas URL.
Assuming your domains are being served by the same web server and you have access to that web server, you can use the manual login procedure: https://developers.facebook.com/docs/facebook-login/manually-build-a-login-flow to login from as many domains as you wish.
Assume your domains are site1.com,site2.com.... Instead of using the Facebook javascript API, you will simply place a plain old Log In with Facebook button on each site which will redirect the browser to the facebook login page as described in the above article. In the state variable you can specify a code which indicates which of your sites is requesting a login. In the redirect you will use a single service domain which you assign to your web server (e.g. fb.mywebserver.com) and which you specify as the verified redirect url in the facebook login settings page. All the sites will redirect to this same url, avoiding the problem of supporting multiple domains.
Once the user has logged in, the browser will redirect to fb.mywebserver.com and pass it the state, which tells you which site is requesting login and a code which you can use on the back end to retrieve the user's info using the Facebook graph apis. You store this info with a uid in your data store then using the info in state, you redirect to to the appropriate site including a parameter that indicates a Facebook login (e.g. site1.com?fbc={some uid}). The browser will obediently then call site1.com?fbc... Your web server will receive this request and detect the fbc parameter which tells it to associate the corresponding Facebook logged in user with this site. It can then retrieve the logged in users info using the uid and, for example, return a session cookie for this user along with the page. If you generate the page on the server you can, of course, also include a welcome "user" or alternatively, your client code can do an ajax call to retrieve that information.
From the user's standpoint they press the Login with Facebook button, are redirected to a Facebook login page where they login and then are redirected back to your site in a logged in state. Not quite as nice as having the login popup but likely acceptable.
A similar process can be used for google logins as well
Best thing I've found to do in the development/production scenario is add a "Test App", then add a platform for your development web site - as you have to provide where the "page tab url" lives if you use that as a platform.
Facebook requires your "page url" to be live / accessible if you need to apply for status or permission review.
This got me around the "login in development" / "login in production" scenario.
I want to allow users connect to my website using their facebook account.
First, the user authorizes my application and then I get an access token. Problem is, that I'm supposed on the first time to register the user, and the next time to auto login him based on his facebook email.
How do I create a SECURE way to auto login the user?
I'm using pure javascript, but I can't find any way to create a secure mechanism.
Thanks.
Facebook should handle all that for you - when they come back to your website, they can click the 'login' button(javascript SDK) and facebook should pass you back an access token.
I may, however, have misunderstood the question.