I have generated a Client ID and Client Secret for my application using the Google API Console for my Java web application.
I want to generate an access token to be used in my application to authenticate a mailbox and read mails from there with the help of JavaMail API.
This link has some theoretical information but I could not understand how the tokens can be obtained.
Answer will depend upon where is application running as it determines how access token can be received:
Using OAuth 2.0 for Web Server Applications
OAuth 2.0 for Client-side
Web Applications OAuth 2.0 for Mobile & Desktop Apps
OAuth 2.0 for TV and Limited-Input Device Applications
There are different alternatives or libraries available to get access token depending upon the type of application and different specific mechanisms are defined around it.
So it will be then much easier to dive-in into the specific options available.
Related
I have created a Web API using .net core 5. I have secured the app using the Microsoft Identity platform. Clients app are able to get to the resource based on their scope/role. So I know that my api is secure.
Now, I need to add the API to Azure API Management tool.
So my question is should I enable OAuth from the Azure API Management to secure my web api even though my app is already secured?. What would be the reason that I enable OAuth from API management?
APIM is a proxy to the backend APIs and implementing security mechanisms to give an extra layer of security to prevent unauthorized access to APIs is a recommended practice.
Configuring OAuth 2.0 Server in APIM merely enables the Developer Portal’s test console as APIM’s client to acquire a token from Azure Active Directory. In the real world, customer will have a different client app that will need to be configured in AAD to get a valid OAuth token that APIM can validate.
OAuth is an authorization framework which allows a recognized client to acquire an access token from an authorization server.
As given in this Microsoft Doc, the Microsoft Identity Platform uses the OAuth 2.0 protocol for handling authorization.
Please find below references makes you how OAuth secures the Web APIs/Services:
OAuth 2.0 and Azure API Management
How does OAuth secure Rest API calls
Protect APIs using OAuth 2.0 in APIM
I am writing a google drive desktop application and I am using OAuth 2 to get credentials. I can get creds for just reading, but not changing files. As it is a desktop application, there is no site. It is written in https://developers.google.com/identity/protocols/oauth2/native-app, that I need to "supply a local redirect URI to handle responses from Google's authorization server". So, should the client also be a server and listening on some port locally? If I want to have the app verified, I need to provide Authorized domains and other stuff, but it is a desktop application, again. Or maybe there is a way to allow users to use the app, but with a warning on a consent screen for example for development purposes.
Also how to hide the credentials, that I use to get the token? If I publish the app with the credentials, everybody can just steal them and use them
In order to develop a desktop application which will use the Drive API you will have to use credentials of the web app type for which you will later provide the appropriate redirect URI.
By using OAuth 2.0 in your application, you are the only one who has access to the credentials for the application - unless you share them.
According to the Google OAuth 2.0 documentation:
You start by obtaining the OAuth 2.0 client credentials from the Google API Console. Then your client application requests an access token from the Google Authorization Server, extracts a token from the response, and sends the token to the Google API that you want to access.
For the login process, when the users will log-in to your application, they will use their own credentials and then they will have to authorize the application you have built in order to be able to use the Drive API.
Reference
OAuth 2.0 for Mobile & Desktop Apps;
Using OAuth 2.0 to Access Google APIs;
I'm struggling theese days on the possible way to configure an Authentication + authorization system to consume a REST API from a mobile application.
Scenario:
We've developed 3 independent portals for a big customer that serves several users.
To enable a SSO for the 3 portals we've implemented a SAML authentication system using SimpleSAMLphp.
Every portal has a service provider and they make assertion requests against a central IdP.
The IdP checks username and password against a database where passwords are hashed and stored during registration.
After the login, the authorization on the portals is handled by the session on the server, and so far everything was fine.
Now the customer asked us to develop a mobile application that will require the users to login and access several of their protected resources collected during the usage of the 3 portals.
We've decided to develop a frontend application using ionic that will consume a REST API made in node.js that will serve all the data (both protected and unprotected resources).
Now here comes the question: to authorize access to protected resources on the Api we'd like to use JWT to easily achieve a stateless system.
The doubt is how to perform the authentication? We've the opportunity to check the credentials directly against the database skipping the SAML process, otherwise we've to implement a solution where the SSO IdP acts as authentication provider and then when an attempt is successful the API app will get the response from the idp and then issue a signed jwt to the consumer client. Is this second way a common implementation? Is it possible?
What path do you suggest to follow? The first could be very easy to achieve, but since we're using html+js for the app's frontend, if we decide to use the second solution probably in the near future we could recycle some code from the app to modernize some functions on the web portals, maintaining the jwt pattern and consuming the new Api also on the web.
I believe that in this case will be easier to ask a token to the new api using someway the logged in user's data already in the session of the portal. Sounds possible?
I hope that everything was clear, any help will be appreciated!
Thanks
The key goal here is to code your apps in the best way, via
the latest security standards (OAuth 2.0 and Open Id Connect).
SAML is an outdated protocol that is not web / mobile / API friendly, and does not fit with modern coding models.
Sounds like you want to do OAuth but you do not have an OAuth Authorization Server, which is a key part of the solution. If you could migrate to one you would have the best future options for your apps.
OPTION 1
Use the most standard and simple option - but users have to login with a new login screen + credentials:
Mobile or Web UI uses Authorization Flow (PKCE) and redirects to an Authorization Server to sign the user in
Mobile or Web UI receives an access token after login that can be sent to the API
Access token format is most commonly a JWT that the API can validate and identify the user from
The API is not involved in the login or token issuing processes
OPTION 2
Extend option 1 to federate to your SAML Identity Provider - enables users to login in the existing way:
The Authorization Server is configured to trust your SAML based identity provider and to redirect to it during logins
The SAML idp presents a login screen and then posts a SAML token to the Authorization Server
The Authorization Server issues OAuth based tokens based on the SAML token details
OPTION 3
Use a bridging solution (not really recommended but sometimes worth considering if you have no proper authorization server - at least it gets your apps using OAuth tokens):
Mobile or Web UI uses Resource Owner Password Grant and sends credentials to a new OAuth endpoint that you develop
OAuth endpoint provides a /oauth/token endpoint to receive the request
OAuth endpoint checks the credentials against the database - or translates to a SAML request that is forwarded to the IDP
OAuth endpoint does its own issuing of JWT access tokens via a third party library (if credentials are valid)
Web or Mobile UI sends JWT access token to API
API validates received JWT access token
There seems to be an inconsistency in the Slack API docs in that the OAuth flow requires a client_secret be provided as part of the exchange of the code for the OAuth token as documented at https://api.slack.com/methods/oauth.access
However the client secret then needs to be embedded into the mobile app which goes against Slack's recommendations at https://api.slack.com/docs/oauth-safety which states:
Your Client Secret should be treated delicately. It is how you securely identify your application's rights and identity when exchanging tokens with Slack. Do not distribute client secrets in email, distributed native applications, client-side javascript, or public code repositories.
Are there any best practices available in terms of how to manage this discrepancy where the client secret seems to be required for auth but at the same time should not be embedded into the mobile app?
Slack only supports the Authorisation Code Flow for OAuth2.0 but it doesn't support public clients only confidential clients. It doesn't support the PKCE flow either.
Their FAQ page suggests using the RTM API if you a re developing a mobile app:
What are some real-world scenarios for 2-legged OAuth?
Is it only applicable for mobile/desktop apps?
2-legged OAuth (aka. the Client Credentials flow in OAuth 2.0) is useful when a client wants to access certain resources without disclosing its primary client credentials to the resource API. The client would authenticate to an Authorization Server to get a derived token that it can present to the resource API to get access to the protected resources.
Getting the token and presenting it is done in a standardized and interoperable way without pestering the resource API with different authentication mechanisms. It also makes revocation of access easier because that is controlled in a centralized fashion on the Authorization Server, independent of the client's primary credentials. See also: How does 2-legged oauth work in OAuth 2.0?
It is applicable across mobile, desktop and web applications although keeping a client secret in mobile and desktop applications is arguably hard so it is most suitable in server-side environments.
A real world scenario is a batch script that fetches data from a remote API and processes it.
2 legged auth is for server to server authentication on behalf of the application with no end-users involved.
For example, your application on Google AppEngine makes a request to Datastore (Database from Google Cloud). This uses 2 legged auth with JWTs.
Instead, if your application makes a request on behalf of the end user to read the user's Google Drive files, 3 legged auth is used.