Intro

This page explains how to use OAuth2.0 Client Credentials grant (defined within the RFC6749) with GEANT AAI Service.

Examples

This section contains some practical examples of where the Client Credentials grant can be effectively utilized along with sequence diagrams depicting the flow.

Background Jobs

Scenario

Applications often run jobs like data synchronization, backups, or batch processing tasks that require access to APIs (other client integrated with GEANT AAI Service) but are not triggered by a specific user action. The Client Credentials grant provides a way for these jobs to authenticate against the necessary services without requiring user interaction, streamlining automated processes within the application's ecosystem.

Sequence diagram

Aggregated Data Services

Scenario

Services that aggregate data from multiple sources (other clients integrated with GEANT AAI Service) and provide a unified API to clients can use Client Credentials to authenticate with those sources. This is common in financial services, market data analysis, or news aggregation platforms where the data needs to be fetched regularly and reliably without user involvement.

Sequence diagram

Example requests

Client Credentials flow

curl -X POST "https://proxy.aai.geant.org/OIDC/token" \
     -H "Content-Type: application/x-www-form-urlencoded" \
     -d "grant_type=client_credentials&client_id=<CLIENT_ID>&client_secret=<CLIENT_SECRET>&scope=api"

{
    "access_token": "eyJhbGciOiJFUzI1NiIs...",
    "token_type": "access_token",
    "scope": "api",
    "expires_in": 3600
}

Token introspection

curl -X POST "https://proxy.aai.geant.org/OIDC/introspect" \
     -H "Authorization: Basic Q0xJRU5UX0lEOkNMSUVOVF9TRUNSRVQ" \
     -H "Content-Type: application/x-www-form-urlencoded" \
     -d "token=eyJhbGciOiJFUzI1NiIs..."

{
    "active": true,
    "scope": "api",
    "client_id": "<CLIENT_ID>",
    "exp": 1715761201,
    "iat": 1715757600,
    "iss": "https://proxy.aai.geant.org",
    "token_type": "Bearer"
}

Support

In order to check whether the Client Credentials grant is supported by the particular instance of the Authorization Server, server metadata needs to be checked.
Although the Client Credentials grant is an OAuth2.0 grant, information on support should be checked in the OpenID Connect Configuration as the Authorization Server is not publishing a separate OAuth2.0 Authorization Server Metadata.

Client Credentials grant is advertised in the metadata by the client_credentials entry in the grant_types_supported property. 

OpenID Connect configuration for eduTEAMs can be found at https://proxy.aai.geant.org/.well-known/openid-configuration.

Client registration

Willingness to use the Client Credentials grant needs to be expressed at the moment of registration of the client in the GEANT AAI Service and for obvious reasons applies only to confidential clients. 

You can find more information about the process of client registration at How to connect a new service to the Geant AAI Service.

Supported client authentication methods

Currently, only password-based authentication methods are supported (see section 2.3.1 of the OAuth 2.0 Authorization Framework - RFC6749 specification for more details).

References

• The OAuth 2.0 Authorization Framework (RFC6749): https://datatracker.ietf.org/doc/html/rfc6749