OAuth endpoints

This section explains the OAuth API endpoints within Onegini Access. It's divided into the following subsections:

For details about the OAuth endpoints we refer to the OAuth specification.

Introduction

Roles

OAuth defines four roles:

• Resource owner: the user
• Authorization server: Onegini Access. It's responsible for managing tokens.
• Client: a website or app that wants to access the user's resources. Resources can be anything: personal data, documents, transactions, signatures, images, etc.
• Resource server: a server that contains the user's resources that are being accessed by the client. It grants access to the resource when the client provides a valid token. It is also referred to as Resource Gateway.

Flows

The OAuth 2.0 specification describes the following flows to obtain tokens:

• Authorization code
• Client credentials

Onegini Access supports all of these flows. However, only the authorization code grant and client credentials grant are recommended.

When to use which flow:

• The authorization code flow returns an access token that gives access to resources of a specific user. For example, when the user wants to check their insurance policy, the resource server needs to know on behalf of which user the client wants to access the policy. User interaction is often required during this flow.
• The client credentials flow returns an access token that gives access to resources for a specific client. For example, when the user requests the general terms and conditions document, the resource server needs to know which client requests access to this document. The resource server does not need to know on behalf of which user the client requests access. Obtaining the access token can be automated and does not require user interaction.

Authorization endpoint

The authorization endpoint is used in the authorization code flow. In this flow, the Onegini Access sends an access grant to the client. The client can exchange this access grant for an access token by calling the token endpoint.

Endpoints: GET /oauth/authorize or GET /oauth/v1/authorize

Example request for the authorization code flow:

GET /oauth/v1/authorize?response_type=code&client_id=exampleApp&state=xyz&redirect_uri=https%3A%2F%2Fclient%2Eexample%2Ecom%2Fredirect HTTP/1.1
Host: onegini.example.com

Example success response for the authorization code flow:

HTTP/1.1 302 Found
Location: https://client.example.com/redirect?code=myAccessGrant12345&state=xyz

Specification

See the OAuth specification section 3.1 and the specification for Proof Key for Code Exchange by OAuth Public Clients (PKCE).

Authorization extensions

This endpoint allows additional request parameters. None of them are required. This section describes the parameters that are specific for the Onegini Access.

idp

Specifies the identity provider for the authentication. The value is the identifier of the identity provider in Onegini Access.

Example value: idp=idpId

Example use case: an application that supports registration via an identity provider for future customers (prospects) and another identity provider for existing customers. Both identity providers would be configured for this application.

external_idp

Preselects the external identity provider in Onegini CIM for authentication. The value starts with urn:com:onegini:saml:idp: followed by the identifier of the identity provider in Onegini CIM. This feature requires Onegini CIM to be used as an identity provider.

Example value: external_idp=urn%3Acom%3Aonegini%3Asaml%3Aidp%3Adigid

Example use case: an application that authenticates the user with the third party identity provider via Onegini CIM but wants to skip the login screen of the latter.

external_idp_custom_param.*

This parameter can be used to populate a key value map in the Onegini Extension as part of the SAML Authentication Request. The key value map can be used in the Onegini CIM product for customizing styling or logic in combination with the Session API. This feature requires Onegini CIM to be used as an identity provider.

Example value: external_idp_custom_param.key1=val1&external_idp_custom_param.key2=val2&external_idp_custom_param.key2=val3

This example shows the ability to pass multiple keys: key1 and key2, and multiple values for a single key: key2 has values val2 and val3.

Example use cases are described in the extension custom parameters topic guide.

app_view

Indication for Onegini CIM that the pages are shown within a mobile app. Passing this parameter is only needed when a web client is used for a mobile device (not recommended). The default value for mobile apps is mobile.

Example value: app_view=mobile

Example use cases: * a login page that should not show the mobile login button when the user visits the login page from within the mobile app. * Pages shown in the mobile app should not get a navigation menu.

language

Specifies the locale for translations during the authorization flow.

Example values: en or en_US

The contents of the language parameter are parsed as Java Locale. Supported formats for the language parameter:

• languageCode, example: en
• languageCode_countryCode, example: en_US
• languageCode_countryCode_variant, example: en_US_east

Example use case: the registration flow for the application should present all screens in the same language.

hook_context_custom_param.*

This parameter can be used to populate a contextCustomParams key value map in the Access Token Web Hook and User Details Web Hook.

Example value: hook_context_custom_param.key1=val1&hook_context_custom_param.key2=val2&hook_context_custom_param.key2=val3

This example shows the ability to pass multiple keys: key1 and key2, and multiple values for a single key: key2 has values val2 and val3. The contextCustomParams key value map, for above example value, will have entries:

Key	Value
key1	["val1"]
key2	["val2", "val3"]

Example use-case: providing context like 'on_behalf_of', 'on_behalf_of_type' to make integrating with a Externalized Authorization product possible.

Authorization error extensions

Apart from the standard error parameters provided by the OAuth specification, in some error scenarios additional parameters are returned. These parameters are meant to give more information about the specific error that happened.

Error cause parameters

Onegini Access uses external Identity Providers to authenticate users. In some scenarios authentication can fail, but it can be a bit unclear why it failed.

In case the SAML IdP is used and authentication failed due to a malformed request or due to some user interaction, the generic SAML error will be available in onegini_saml_error. To provide additional information the onegini_error_cause parameter is sometimes added in case of a specific error during the authorization flow.

The onegini_saml_error and onegini_error_cause parameters are included on top of the standard error response as defined by the OAuth specification RFC6749, section 4.1.2.1. Currently, these fields are only provided when a SAML IdP is used for authentication by the end user. The value of the onegini_saml_error attribute contains the SAML response status (e.g. urn:oasis:names:tc:SAML:2.0:status:NoPassive) of the SAML response that was sent by the external IdP to the Onegini Access. For a list of SAML status codes see the SAML 2.0 core specification, section 3.2.2.2 The value of the onegini_error_cause can contain more detailed information about the error cause like custom error codes, which are especially useful in processes like on-boarding. Values can be, for example, no_existing_customer, invalid_birthdate, fraud_detected or whatever is defined as custom error in the user journey.

Token endpoint

The token endpoint returns an access token for the following flows:

• authorization code
• client credentials

Endpoints: POST /oauth/token or POST /oauth/v1/token

Example request for the authorization code flow:

POST /oauth/v1/token HTTP/1.1
Host: server.example.com
Authorization: Basic ZXhhbXBsZUFwcDp0aGVTZWNyZXRUaGF0QmVsb25nc1RvVGhlRXhhbXBsZUFwcA==
Content-Type: application/x-www-form-urlencoded

grant_type=authorization_code&code=myAccessGrant12345&redirect_uri=https%3A%2F%2Fclient%2Eexample%2Ecom%2Fredirect

Example success response:

HTTP/1.1 200 OK
Content-Type: application/json;charset=UTF-8
Cache-Control: no-store
Pragma: no-cache

{
  "token_type": "bearer",
  "access_token": "myAccessToken12345",
  "refresh_token": "myRefreshToken12345",
  "expires_in": 900,
  "profile_id": "static"
}

Specification

See the OAuth specification section 3.2 and the specification for Proof Key for Code Exchange by OAuth Public Clients (PKCE).

Client Authentication

The token endpoint supports two types of client authentication:

• Client Secret
• Private Key JWT

For more information, see Authentication Methods documentation.

Revoke token endpoint

Use this endpoint to revoke tokens. The Onegini Access will immediately make them invalid, but clients or resource servers will not receive a notification. When the resource server requests token introspection for the token, the response does indicate that this token is no longer valid.

Endpoint: POST /oauth/revoke or POST /oauth/v1/revoke

Example request:

POST /oauth/v1/revoke HTTP/1.1
Host: server.example.com
Authorization: Basic ZXhhbXBsZUFwcDp0aGVTZWNyZXRUaGF0QmVsb25nc1RvVGhlRXhhbXBsZUFwcA==
Content-Type: application/x-www-form-urlencoded

token=myAccessToken12345&token_type_hint=access_token

Example success response:

HTTP/1.1 200 OK
Content-Type: application/json;charset=UTF-8
Cache-Control: no-store
Pragma: no-cache

Specification

See the OAuth specification for token revocation and the specification for Proof Key for Code Exchange by OAuth Public Clients (PKCE).

Note for refreshing and revoking the access token: When a public client uses the authorization code grant type with PKCE, the request parameter client_id is mandatory. For confidential clients both the client id and the client secret are sent as basic authentication credentials via the authorization header.