How to include the JWT for a Google Action endpoint? - actions-on-google

Our architecture currently has all public access going through Kong. It validates all incoming requests contain a valid JWT. Is there a way to tell Google Action to include the JWT when configuring the webhook fulfillment?

Related

RESTful API with Google API and OAuth2

As the title says, I want to create a RESTful API (stateless) that will access Google API endpoints. First I want to authenticate the user and then use that token provided by Google to access Google Calendar API.
This is the current flow of the app:
Flow
Is there any other way to achieve this since my Nodejs service is signing an already signed JWT token provided by Google (I need to track expiration times for both access tokens)?
I am doing this because I don't want to use Google's access token for my own endpoint authentication.
This is a valid embedded token pattern, where the Google access token is just a custom claim in your own access token.
The client can call your API, using its main token
The API can authorize correctly, based on claims and scopes you have issued for your own data
When required, your API can use the embedded token to get external Google data the user has consented to
Your API should handle 401s from Google APIs in the standard way, as in this code of mine.
Your nodejs service is actually implementing 2 roles here. Consider separating these into a token service and a business service:
Token issuing. A technical job most commonly done by an authorization server.
REST API. A business focused component.

What is the advantage of a custom API in Auth0?

Question
I got a problem with understanding some basic thing about auth0, probably someone can help me out.
In the tutorial SPA + API one of the first lines in the TDLR is this:
Both the SPA and the API must be configured in the Auth0 Dashboard
I dont understand why I need to configure the API on Auth0. My code seems to work so can anyone help me understand if I do something wrong or what the advantages are if I actually add a custom API in my dashboard?
Setup
SPA (React)
Auth0
REST API (ktor)
What I do
Created a SPA on Auth0
Login on my SPA through Auth0 to get a JWT (google token)
Sending the JWT as authentication bearer in my calls to the REST API
REST API verifies the JWT token with a JWK provider using the Auth0 url mydomain.eu.auth0.com/.well-known/jwks.json.
Authentication seems to work
Great question, I am assuming that your authentication request includes audience parameter which represents your custom API(Rest API)right now. In oauth2 terms, it is called Resource Server. Each resource server can have many permissions which you include in the scope when initiating the authentication request. Let's step back and talk about the token format. Auth0 issues token in two formats:
Opaque strings: When not using a custom API
JSON Web Tokens (JWTs): When using a custom API
https://auth0.com/docs/tokens/reference/access-token/access-token-formats#how-does-all-this-affect-the-token-format-
As explained above link, the token format depends on the audience (Custom API) parameter. Therefore, when the authentication request includes audience, auth0 issues JWT token with all necessary permission. Then, you need to validate the JWT token in your API server before returning the resources to your front end client.
It should make sense why you need to create custom API in auth0 and define permissions. If you do not create custom API in auth0, there is no way to know what kind of permission you need in the token which will generate an error(invalid audience specified)

registering a rest API with OAuth

I have written a web application which makes REST API calls to a message broker. The message broker contains already written REST APIs to which can be used to get message broker data. The message broker is written in a way in which each REST API call sends the user name and password which is encoded with base64. I need to make a login to my web app and authenticate it with OAuth.Does anyone know how to do this? How to authenticate the REST APIs with OAuth?
Step 1: Add OAuth 2.0 to your web server. This is very standard with lots of libraries available. You did not specify the Identity Provider that you will use (Google, Facebook, Auth0, Okta, etc), but each vendor has documents and libraries for you to use in your desired language.
Step 2: Add an Authorization Header to your API calls. The standard method is to add the HTTP header Authorization: Bearer access_token when making an API call.
Step 3: Add OAuth token verification to your API. When your API receives a request, it extracts the Authorization header and verifies the Bearer token. How this is done depends on the Identity Provider. For example, some vendors provide a Signed JWT (which you verify with the vendors public certificate), others provide an opaque access token (which you verify by calling the vendor's token endpoint). Add internal caching of tokens so that you don't need to verify on every API call.
If you understand OAuth 2.0 the above steps are straightforward to implement. If you don't Oracle has a set of videos which are excellent for getting started understanding OAuth.
Oracle Cloud Primers
If your desired OAuth implementation does not require users logging in and is a server to server service that you control on both ends, then you can use just part of OAuth which is Signed JWT (JWS). You create a Json data structure with your desired content and sign it with a private key. This creates a token that you can use in the above steps. You would then validate the token using your public key. You can use self-generated keypairs generated by OpenSSL or similar products for your signing and verification.

OIDC - What's to stop someone from spoofing a JWT access_token?

When you authenticate with an OIDC provider you get back an id token and if you specified scopes for an API you get back an access token so that client applications can make requests to protected resources on the end user's behalf. Typically the access token is also a JWT.
But what is to stop someone from spoofing one of these access tokens, and creating one and passing it to an API? I understand there are safeguards to prevent modification because the signature will be different than what any validation logic is expecting, but what if a malicious user created a brand new one manually? Especially because these tokens can be validated 'in place' by any API that requires an access token (not all API's use the introspection endpoint... especially with a JWT). I do understand there is metadata around the signing keys for JWT's from OpenID Connect providers and that it is available in the OIDC discovery document. For example, here is Google's JWK metadata. Given that you have signing information publicly available, and JWT access token's can be validated without any requests to the OIDC provider, how are JWT's secure? What is preventing a person from creating one and passing it as a bearer token to an API that requires an access token?
But what is to stop someone from spoofing one of these access tokens, and creating one and passing it to an API?
Spoofing and reconstruction of signature is nearly impossible without the private key (assuming you are using asymmetric signing algorithm like RS256) that used for signing the original JWT.
The JWK information available via OIDC discovery document only contains the public key.
Also Use HTTPS for authorization / token exchange to avoid token sniffing.

Forcing external apps to use the API

I have a website allowing authenticated users to submit and edit data. I also want to offer a REST API as part of a chargeable service.
Now the problem is that a non-paying user could theoretically use the same calls my website uses as API for authentication and sending data from his external application since it is very easy in the browser to see the endpoint what and how exactly the data is being sent to a website.
How can I protect my website from such usage and force the user to use API for external access?
Actually you cannot prevent people making requests to a public API. You can just validate the user when a request arrives. So there are more than one approach to solve this problem.
I would provide a token per session for each user and validate the rest API request at back-end.
Use OAuth2. So you will give paid user secret id and key then they will ask for the access token to access the API's using secret id and key.
Read about public/private key encryption https://en.wikipedia.org/wiki/Public-key_cryptography
Read about oAuth
https://oauth.net/2/
I have used passport to implement oAuth2 in laravel. passport is oAuth2 implementation and available in other languages also.