After user being logged in with Google OAuth - is it possible to check if later user get logged out from Google?
Scenario:
User logged in in Google
User logged in on mysite.com using Google OAuth, and login state stored in session for 1 year.
User logged out from Google, but forgot to log out from mysite.com
After one week someone stoled user's laptop. Thief won't be able to use Google but will be able to re-use logged in user session on mysite.com
I wonder what are the ways to prevent such situation?
I don't want to put this burden on user - log out him from mysite.com and ask to log in again every day.
Would like instead use something automatic like:
When you logged in with Google OAuth you get some sort of ID
Every day you validate that that original session is still active, by calling something like
google.com/api/is-original-session-still-active?id=ID
Note: I suspect that you have your terminology incorrect i suspect you are using Openid connect and not OAuth2 to sign-in your users. However i will answer this question based upon Oauth2 as that's what you say you are using.
Oauth2
Oauth2 is used to grant an application access to a users data. When using an oauth2 token you are acting on behalf of the user. There is in fact no user interaction when using Oauth2 tokens.
If a user consents to your application accessing their data you will get an access token and a refresh token. Access tokens are good for an hour. Refresh tokens are long lived and will give you access to a users data for as long as the user doesnt remove your consent and that you use it at least every six months.
As Oauth2 is without user interaction there is no way to use it to see if a user is logged into their account. There is actually no Google api that would give you this information. This would IMO be considered privet user information and not something that google should be sharing with third party applications.
Suggestions
You may want to consider some changes to your application.
implement logout everywhere. If the user changes their password then all of the devices they have logged in should automatically need to be re-authenticated.
Your sessions should be good for only a week or two and you should enable sliding.
Tell your users to remove the consent of your application to their data this will also force them to have to relogin.
Specifically to know about user account security events that could impact users of your app if your app is using Sign In With Google, consider registering your app to receive events for Cross Account Protection.
Related
TLDR: I've been struggling with the new Sign in with Google functionality and especially the part how I can let the user stay signed in. What I understand from the docs is that Google only tells "this is a user who would like to sign in" but basically I would still need to create my own backend to track that user.
Note this question is about the new Sign in with Google functionality, all the guides/questions I can seem to find are about legacy sign-in and this is quite well described here:
https://developers.google.com/identity/sign-in/web/server-side-flow
What confuses me most is basically already stated in the beginning of the guide:
https://developers.google.com/identity/gsi/web/guides/overview?hl=en#user_sign-in_to_your_site
You'll manage per user session state for sign-in to your site.
User sign-in status to their Google Account and your app are independent of each other, except during the sign-in moment itself when you know that the user has successfully authenticated and is signed into their Google Account. Users may remain signed-in, sign-out, or switch to a different Google Account while maintaining an active, signed-in session on your website.
I understand the basic principle behind OAuth and the part where you have to exchange the authorization code for an access token and you can verify this access token (which is perfectly described in the legacy guide), but this is now only required for OAuth2 in order to access personal data. If I understand correctly this access token can be used as an identifier for a specific session (as alternative to a password or session cookie).
With the new sign in policy you will only get a JWT which identifies the user. Also apparently the only way to get a JWT is as a response when the user clicks the Sign in with Google button and selects the account in the consent screen (which ideally should only occur once).
What I actually want to achieve is that when a user enters the site I want to send a request "Hey Google this user is visiting my site, do you recognize this session and is it still valid".
Maybe I'm thinking way too difficult, but what I just don't understand is how can the new Google Login actually help me remember and validate users?
After some more digging around I found a lead on this page: https://developers.google.com/identity/gsi/web/guides/migration#object_migration_reference_for_user_sign-in
Basically what I am looking for was provided by the depreciated GoogleAuth.isSignedIn.get() function, but the notes clearly show:
Remove. A user's current sign-in status on Google is unavailable. Users must be signed-in to Google for consent and sign-in moments.
Combined with the prior statement:
You'll manage per user session state for sign-in to your site.
To validate the assumption I did some testing with other web services where I logged in using Google, revoked the log-in access for that website from the Google console and when revisiting that website I was still logged in to the website.
My conclusion:
Google login only verifies the initial login
Google basically responds with "Yes this is a valid user"
I have to keep track of the user session using cookies/databases myself
Note: This is the first time I'm trying to implement a social login API, so thanks for bearing with me and helping me out!
I am developing a web application and I have a login and registration system already developed. Now, I am thinking of adding Facebook and Google+ login - with a backend. I went through their docs and other tutorials and they require to implement considerably a lot of things.
But, since I have a registration system already, I thought of doing something like this:
Have the social login buttons on the login page.
When the user clicks on a social login button and authorizes the app, the user data is returned from Google+, for example.
Now, instead of proceeding with the OAuth procedure like getting the user ID, secret ID and contacting their server from my server for token verification and getting data, is it possible to just use the data returned (after the user authorizes) and do the normal registration with the registration system that I already have?
These are the advantages that I see in doing this:
No need of extra code or database fields like token ID, etc.
User can add a password to their account whenever they want and login to the site or access their account by logging in through Facebook or Google+ given that they use the same email ID.
It's enough to use the social login providers' API once - the first time the user logs in (which technically registers the user to the site).
I know the advantages are the same when following the full OAuth2 implementation, but what difference does it make?
Now my questions are:
Is it OK to cut short on the social login as mentioned above?
Will I be losing any obvious advantage doing so (given that I already have a registration system in place)?
If yes, is anyone else cutting short on the flow in their website?
The system proposed by you has certain flaws, especially security related flaw. I would give you to the point answer:
You will send data from client after getting it from google+ or other provider and use your registration process implicitly.
This approach is wrong as I myself as an attacker can send you the data from google+ using my clientid for an app. Will you register or login using the info I am sending? I can pretend to be anyone in your system if you do that.
Is it OK to cut short on the social login as mentioned above?
Will I be losing any obvious advantage doing so (given that I already have a registration system in place)?
If yes, is anyone else cutting short on the flow in their website?
No. (see the reason above).
No. You won't be losing advantage as you already have system in place. Most of the sites have a system in place for normal registration. They give oauth login by leveraging it. Some will say that the password is cumbersome or such, but all famous sites provide login and password including SO.
Now the question comes, how to simplify the oauth system given that you already have a system in place.
I recommend this(I would assume Google as a provider) flow with things starting with dot are what you need to do:
You have a Google login button.
User click on Google Button.
The User is redirected to the Google site.
The user gives you permission.
Google redirects and give you a token.
You can now send info and token to your server. (You need to send only token as backend will get info. Otherwise, a user with valid google+ token for your website can send you any info).
Backend verify token and match that "aud" is equal to your client id. Or it can happen via a library. You will need to give only your client id.
Backend get profile info from token in case of Google+(Name, email) while verifying which you can store as part of your registration process or login process if that email already exists. You can store google id of user also. This is useful as some provider like fb don't always provide email for every account. (For some fb don't give email but for majority of cases it give you the email.)
Backend send back session info or jwt token or any other time bounded process which tells that the user is login.
Your user can login via email also. If he isn't already registered then, then he will need to register. Otherwise, using forget, he can set password or from accounts settings he can set password.
You also need to be careful if the same user is connecting via a different provider, he need to have the same account in your system which you can handle via email.
Kevin,
Authentication is a complex procedure involving lot of measures to ensure security. Hence Web-application/ App developers, delegate this critical piece of work to Identity providers like Google, Microsoft, Facebook etc. These Identity providers are trusted by the app developers and more importantly the consumers trust them too.
Why do app developers provide third party/ social logins? Because, it gives the users of the app some advantages.
They don't have to create new account with the app and remember the new set of credentials. Instead they can use the same credentials they are using with the Identity provider, to gain access to the app. This is huge.
They don't have to trust the app completely, means how the sensitive information like passwords, security questions are handled in the app, as they are not providing any sensitive information directly on the app. Only needed public information is fed to the app from the Identity provider. This is huge too.
No need to worry about the system compromise and leak of sensitive information as all Open ID providers have better security policies in place. This gives consumers a high degree of confidence when using your system through third party logins.
"All the advantages you mentioned will be great for the app developers
at the cost of disadvantages to the consumers of the app."
Lets put the consumer disadvantages on the side and look at the advantages you mentioned:
No need of extra code or database fields like token ID, etc.
You still need code/setup to validate your own tokens. You have to add more logic to verify the external tokens, but the consumers will have the advantage of using the external providers like they are in any other application.
User can add a password to their account whenever they want and login to the site or access their account by logging in through Facebook or Google+ given that they use the same email ID.
This is little confusing as users may choose external provider, so they don't have to remember a new password. Also, the account validation process is different if you use external login vs id/password login. If you are willing to provide both, then you already have the system in place, to verify the account for external logins. Then your first advantage is void and you are better of using Open ID spec.
It's enough to use the social login providers' API once - the first time the user logs in (which technically registers the user to the site).
This approach adds confusion to the flow for consumers. They expect to see a login screen from third party provider for authentication (when they click on google+ or FB), but instead they see your login screen.
Instead of cut short approach, it would be worth to use the complete flow. You might add more logic to handle the token verification with external providers, but, actual complex logic of token validation is delegated to the external providers. This adds no confusion to the end user and they can trust your application easily through social id providers. Even though, users can authenticate through social Id providers, it is always a best practice to have the profile object of that user in your system (without the sensitive information like password).
Since you have your own registration process in place, this may not be a huge advantage. But, please look into the open source implementation of any of the Security Token Service (STS) providers, to see if you can borrow some of the features for validation external providers.
Please let me know if you have any questions.
Thank you,
Soma.
I have a Google Marketplace app that is currently using OpenID for federated login.
When an admin installs the application to the domain users are able to login via a site.com/login/domain.com link.
Currently when a user uses this link they are being asked to consent once again for "Know who you are on Google" scope. I understand that this is something to do with my OpenID realm not matching. The problem is I cannot find where to edit that realm in the new console. My research shows that OpenID has been abandoned for OAuth2 authentication. Please correct me if I am wrong.
Is there a good example anywhere that shows how to authenticate a user that an admin has already granted scopes for on the domain so that they do not get asked to consent again? I've looked up and seen documentation to make a call to https://accounts.google.com/o/oauth2/auth but I'm unaware of how to actually skip the user consent since the admin already authorized the scopes domain-wide.
Using C# but I'm open to any example as I'm sure I can figure out how to get it back into C#.
If you read this post on the google groups, then it seems it is intentionally :
This is an intentional change to more precisely communicate to users
the set of permissions that is being granted. Through knowledge of the
user's email address it is possible, via indirect means, to locate the
user's profile address. In the interest of more accurate disclosure,
thus, we are prompting users to approve such disclosure.
The new tokens issued include permissions to obtain public profile
information, in accordance with the modified text. You can use
https://developers.google.com/accounts/docs/OAuth2Login#userinfocall
to obtain the subset of user's profile information that is publicly
linked from the user's profile. The user's profile Id, which is always
public in that endpoint, is also a more reliable identifier for the
user (as email addresses can be changed on accounts). We recommend
that you store the user's profile id to ensure that email changes
don't cause account confusion.
We are using google oauth2 permitting users to use their existing google accounts to log in to our system.
After being authenticated what is the proper way to manage active user session in our app for ex.
Let's suppose the user has logged in to our system with google account A. Then user logs out/changes google account to account B but not within our app but rather from its gmail. Should we also log him out him from our app???
(which seems to me bizarre and impossible as soon as there should be google API to check that the given user at the given time is logged in to google services).
The only way which seems to me reasonable is to invalidate user session after given timeout and only then we could make user re-pass oauth2 authorization flow.
Thanks in advance for your help.
The access_token or id_token your acquire from the Google OAuth2 Login flow is not coupled with the login sessions in the various Google apps (gmail, plus, ....).
There's no way for your app to know that the the user logged out of his gmail. Your app shouldn't care.
If your web app makes it clear to the user what account has been used to login initially (by displaying a username/picture or other info retrieved from the Google User Info call you should be ok.
Most users will not try to link your web application session with a gmail session for example.
I asked various questions about my problem (here and here) and I also asked in the #oauth & #openid freenode's channel on IRC. (this is note an "UP" question, it's an other problem)
I'll sum up my project configuration : Anyone will have the possibility to create an app that can use my API. To start, I'll work on my API and a Web based app, but the documentation about the API will be public. It's a bit like Twitter API.
The problem I face is how can I be sure which user is using the API (to retrieve his personal data, like your tweets), even if the User is using an app that I don't know who make it (again, like twitter and all the apps around).
I googled a lot and with the help of the previous answers given, I took a look at OAuth.
As far as I understood the way OAuth works, here how :
A user visit an app that use my API (web, mobile, whatever)
The apps redirect the user to the API for the authentication (I'll use OpenId) and the authorization (OAuth). This is a bit odd since the API will have a web interface for the login and the authorization (I suppose this is how it works since Twitter do that)
The API redirect the connected user to the app, with some tokens. In these tokens, there is a token representing the user that the app must store in order to indicate to the API which user is using it currently (Am I correct?)
So far, everything goes well. But what I can't figure it out, is when the user quit the app and goes again : how the app can remember the user is the one that used it before ?
(Before some of you bring me the cookie answer, I'll remark this is a simple example, it would be the same if the user clear his cookies, format his computer or change its computer.)
The only solution I can find, is when an unauthenticated user (without a remembering cookie for example) goes to the app, the app redirect him again to the API to authenticate himself, but this time, the user won't have to re-allow the app (authorization) since it already did it. The API will then return the user to the app to allow him to play with this.
Is this the proper & secure way to do it ?
The #OAuth IRC channel told me about the new protocol, WebID, but this is currently in pre-draft mode and I don't want to use something that will change continuously in the future :/
Thank you very much for your help!
Short answer: OAuth results in an authenticated access token. That access token is tied to ONE user. And as long as the access token is valid. The third application can do whatever the API allows the access token to do.
Long answer:
The thing with OAuth is that it does not "Log in" a user. OAuth gives third party applications what is called access tokens which can be used to access data on behalf of a user whether he/she is logged in or not.
Many services restrict their access tokens. Twitter for example issues two types of access tokens, read-only, and read/write. But there is no concept of logging in to use APIs. While an access token is valid, a third party application can access the user's data, and change things without a user's explicit interaction.
Most API providers have functionality to revoke access tokens. That is what happens when you in twitter look at your Connections page . See the revoke access links?
Personally I love the OAuth approach. As an API provider, you can control what access tokens are allowed to do, and the user can kill bad applications from using his/her resources. OAuth is secure as far as authentication goes. Third party applications do not get hold of user's passwords. But once authenticated they can do whatever your API allows.
if we take a look at how Twitter works, I think the missing point is an other layer to the project: The Official website:
The thing is, when you want to allow any 3rd party application to use Twitter, this application redirect you to the OAuth page of the Twitter API, IF you are connected, but if you aren't, it redirect you to the login page, which is located at http://api.twitter.com/login
(I don't know if keeping the api in api.twitter.com for loging an user, instead of just twitter.com is correct, but this is just semantics)
So, the workflow would be:
A user goes to a 3rd party application (like a website)
This third party redirect the user to the API for Authorization
The API redirect the User to the website for Authentication first
The official website redirect the User to the OpenId provider (or Facebook connect)
The Authentication is made (via multiple requests)
The website redirect the user to the API after he's successfully authenticated
The user allow/disallow the permissions asked by the 3rd party apps
The API returns to the 3rd party apps.
The User can now use (or not) the application.
This implementation have 2 problems:
Every time an User ins't authenticated (cleared it's cookies, connect himself from an other computer, etc), he will have to go through the Authentication method, by being redirected to the Official website and then being redirected to the 3rd party application (the API would be transparent, since it has already allowed the application to access his data).
All those layers would certainly lost the User on the Authentication process with too many redirections.
A possible solution would be to store the user's access_token, for example in the case of a mobile app, but with a pure html/css/js oriented app, this isn't possible. A login/password in the 3rd party web application that would match the user to the access_token of the API would be an other solution, like Seesmic (I think), but this is just useless (for us, not Seesmic) : the idea of not having the user's password become useless.
This is a possible explanation but I would require more details on how this is possible and your thought about that solution. Would it work?
(I added this as an answer since it's an (incomplete and not so sure, I agree) one.