What is the usage of the client_secrets.json file? - google-api

I am working on writing a program using the Google Tasks API in Python. I have downloaded and run the sample application from Google, and it comes with a file called client_secrets.json. I understand that the file is used for OAuth authentication, but my question is should I distribute this file to users? Should I push it to my public source repo? Or is it supposed to be kept secret? If I shouldn't share it, how would other users do the authentication?
Thanks for reading.

The Google API Client Library OAuth2 docs states,
Keep your client secret private. If someone obtains your client
secret, they could use it to consume your quota, incur charges against
your Developers Console project, and request access to user data.
So don't commit or otherwise distribute the file.
If you want to publicly share your application source code, instruct others to use their own Google Developer account to register their own Google Developer project and generate their own app OAuth credentials (client_secrets.json file) for use with their "installation" of the app.
If you were making the application commercially available, you would seemingly need to share the app credentials with them in a trusted, legally protected, or secure manner.

Apparently the client_secrets.json file does not have to be kept secret for installed application. From https://developers.google.com/identity/protocols/OAuth2?csw=1#CS in the "Installed applications" section:
The process results in a client ID and, in some cases, a client secret, which you embed in the source code of your application. (In this context, the client secret is obviously not treated as a secret.)
So if you're making a webapp, keep it secret. If it's a python app that you distribute to users and they run on their own, it does not have to be kept secret.

Related

How to block Google Firestore access from the Google Firestore api

I am working with Google Firestore in native mode and CRUD'ing data within it using the "cloud.google.com/go/firestore" api in Go. Access to the data is wide open as long as you know the project id and using the Firestore API on a server. I don't want to try the rules until I figure out how to secure the data from server attacks that. Again, all the API requires is the project id to access the data so I need to lock that down firstly before I move any further. Rules are only for mobile/web clients from what I read and Server side clients completely bypass the rules. Please help. I do not want to use the Firebase API because attackers can still use the Firestore api to access the data.
It's unclear from the limited information in your question but, your Firestore database is not open to anyone with the Project ID.
The service is only accessible to any thing (human|machine) that has valid credentials. Either humans with e.g. Gmail accounts or Service Account key holders.
In either case, only identities that you've explicitly added to the project will be able to access its resources and then only those with the appropriate IAM roles|permissions.
Google provides an elegant facility called Application Default Credentials (ADCs) that simplifies authenticating clients.
I suspect that your code is using ADCs to authenticate you to the project|service.
Access to the data is wide open as long as you know the project id and using the Firestore API on a server.
If that is a concern, consider disallowing all access in the Firebase security rules for your Firestore database.
Also have a look at my answer here to understand why sharing your project ID is not a security concern, and in fact is necessary if you want to allow direct access from client-side devices: Is it safe to expose Firebase apiKey to the public?. If you don't want to allow direct client-side access, closing down the security rules (as they are by default, unless you choose test mode when creating the database) is the way to go.

Saving organization-wide application settings in Teams app

I have a Teams application (Tab). I am an ISV provider, and provide a multi-tenant application that is installed by customers via Teams App Store in their organizations.
How do I save settings for my application organization-wide for the customers? For example, CustomerA has installed the app and then CustomerB. I want some storage that would be unique for CustomerA and CustomerB and the app, and located in customer's environment. The settings I want to save are not per-user, but per-organization (tenant).
Somewhat similar to "App Data" folder you have in Windows Desktop for example.
Does such a storage exist? Does API for this storage exist?
A tab app is a simply a web application that you render inside of Teams. As a result, what the app does, and where and how it does it, is totally up to you. This includes any data storage you choose to have behind the scenes. For example, your tab could be built in PHP and use MySQL, or built in ASP.Net and use SQL Azure or CosmosDB. It's totally up to you, but you need to implement it yourself, as an ISV.
The important piece to differentiate clients, however, is being aware of the TenantId for each user, so you can look up which client's settings you need from the database. The most simple way to do this is simply the tid property on the Teams tab context. You can read more about that here. Unfortunately, because it's just accessed via Javascript, it's not entirely secure - for a more secure mechanism, you should be creating an Azure Application, and generating jwt tokens that you can authenticate against in your backend. It's a much more complex topic, but hopefully this answer at least gives the background you need. For more info on the security aspects (validating the token etc.), please see this question: How to restrict access to Azure Function to only allow requests from a custom Microsoft Teams App?.

Keeping to Google API quotas with client-side applications

Google APIs can have usage limits, both on a per-user and a per-application basis. For example, the GMail API free tier is limited to a billion daily quota units across all users of your application.
This works for well-designed server-side applications, which can centrally ensure they obey these usage limits. However, I’m not sure how this is supposed to work for client-side apps. As Google’s documentation says,
Installed apps are distributed to individual devices, and it is assumed that these apps cannot keep secrets.
These apps are still supposed to use a client_secret and credentials, but these are assumed to not be confidential despite the name. However, just saying they aren’t secret doesn’t prevent abuse; a user of the app can take the credentials file and use it for a different purpose, perhaps one that uses the APIs more. What can an application developer do to prevent people doing this from burning through all the available quota?
Edit for clarification:
The use case that prompted this is a purely desktop app that doesn’t connect to any service except GMail (see https://github.com/mbrt/gmailctl/issues/48). If it weren’t for a global quota for all users of the app, there would be no reason to worry about individual users at all; they don’t connect to any service except GMail itself.
You could write a server app (a Cloud Function would work) which holds the secrets. Clients call your endpoint with some form of identifier and you return an Access Token. If your users have a browser, they can auth each time; if not you would need to request a Refresh Token which you store and use that to generate an AT.

Authentication using Using DIrectMail SDK?

I want to use the Direct Mail SDK(Java) directly within client application which is distributed across. The way to authenticate users within the application, I need to provide access keys as below,
IClientProfile profile = DefaultProfile.getProfile("cn-hangzhou", "<your accessKey>", "<your accessSecret>");
How can I prevent user to know the Access Keys and still prevent the need of third-party API? Is it possible?
First, it is bad practice to code an application that requires secrets that runs on the client. You should manage everything on the server and provide an API that the client software interfaces with.
Second, there is no way to hide those credentials once passed to the client. You could encrypt the credentials but at some point the client application will need to decrypt them. Even amateur programmers can figure out how you are processing your credentials.
Ignoring the above advice, Alibaba Cloud supports STS which provides temporary access keys. Using your Alibaba credentials, you would call AssumeRole which creates temporary access keys giving the user permission call DirectMail. You can limit the time that the credentials are valid. The range is 900 to 3600 seconds. After that duration the keys become invalid.
Keep in mind that 900 seconds is a long time. A bad actor getting access to those keys could send thousands of emails using your account. Therefore implement strong user authentication, STS and temporary access keys.
If you think that just keeping your interface secret is enough, don't. There are millions of script kiddies on the Internet poking at every IP address. Launch a new ECS instance and you will see attacks within hours.
As you said since it is a Java Web Application(assuming), currently I think of something using similar to JBOSS Vault to store the access keys securely.
If it is some standalone client application still you can use some encryption methodologies to store the data. But this will only prevent easy access to the data/keys. But it is not impossible. The best bet would be creating another third-party API

Store User Credentials on Appharbor

I need to store user credentials in my app. I can store and retrieve the password with protectdata. But as soon as I push a new revision of my app I loose the credentials. It seems like appharbor cleans the ProtectedData Store.
Is this behavior on purpose? Is there a better way to store user credentials on appharbor. OAuth is not an options since it's a ftp account.
System.Security.Cryptography.ProtectedData
Changes to the local instance file system are not persisted across deploys on AppHarbor, so you'll have to store the data someplace else. We generally recommend using Amazon S3. You can use System.Security.Cryptography.ProtectedData.Protect() from the same API to encrypt data written there. Here's some sample code: protect bytes data .net
I'm not super familiar with this API, but you might get into trouble if you app us running on multiple AppHarbor instances using different user accounts.

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