Configure token exchange

You can add a trusted token issuer to exchange tokens received from the configured third-party issuer for WSO2 Identity Server tokens.

Learn how to configure the OAuth 2.0 token exchange flow in your WSO2 Identity Server organization. Refer Token exchange grant for more information on how the flow works.

Follow this guide for instructions.

Register a trusted token issuer

To exchange a third-party token for an WSO2 Identity Server token, you need to register the third-party token issuer as a trusted token issuer in your WSO2 Identity Server organization.

To register a trusted token issuer:

1. On the WSO2 Identity Server console, go to Connections.
2. Click New Connections and click Create on the Trusted Token Issuer.

3. Enter the following details of the trusted token issuer:

   Parameter	Description
   Trusted token issuer name	A unique name for the new trusted token issuer.
   Issuer	A unique issuer value of the trusted token issuer. This is the value of the iss claim in the JWT token generated from the configured identity provider. Example: https://third-party-token-issuers.io/oauth2/token
   Alias	The name by which the trusted token issuer knows WSO2 Identity Server. Usually, the aud claim of the token should include the WSO2 Identity Server organization's issuer value. In case the organization's issuer value is not included in the aud claim, the alias value you assign here will be validated against the aud claim.

4. Click Next and provide the mode of certificate configuration.

   Note

   You can either configure a JWKS endpoint or upload a certificate of the external party. This is required to validate the signature of the assertions sent by the external identity provider.

   • JWKS endpoint: The JWKS endpoint of the trusted token issuer.

   • Use PEM certificate: Upload or paste the public certificate of the trusted token issuer. The certificate should be in PEM format.

     If you have a certificate in other formats such as .crt, .cer or .der, expand here to see how you can convert them to PEM format using OpenSSL

     Convert CRT to PEM

     openssl x509 -in cert.crt -out cert.pem
     

     Convert CER to PEM:

     openssl x509 -in cert.cer -out cert.pem
     

     Convert DER to PEM:

     openssl x509 -in cert.der -out cert.pem
     

5. Click Finish to add the new trusted token issuer.

Enable token exchange in your app

Before you begin

You need to register any one of the following application types with WSO2 Identity Server:

• Standard-based OIDC application
• Mobile application
• Traditional OIDC web application

Currently, WSO2 Identity Server does not support the token exchange grant for single-page applications.

To enable token exchange in your application:

1. On the WSO2 Identity Server Console, go to Applications.

2. Open your application from the list and go to the Protocol tab.

3. Add Token Exchange under the Allowed grant types.

   Note

   To enable refresh tokens for the token exchange grant, include Refresh Token as an Allowed Grant Type. Learn more about how the refresh token grant type works.

4. Click Update to save the configurations.

Try it out

Follow the steps given below.

1. Obtain the JWT token received from the third-party token issuer.

2. Execute the following cURL command to exchange the third-party token for an WSO2 Identity Server token.

   curl --location 'https://localhost:9443/oauth2/token' \
   --header 'Content-Type: application/x-www-form-urlencoded' \
   --header 'Authorization: Basic <base64 Encoded (clientId:clientSecret)>' \
   --data-urlencode 'subject_token=<jwt_token>
   ' \
   --data-urlencode 'subject_token_type=urn:ietf:params:oauth:token-type:jwt' \
   --data-urlencode 'requested_token_type=urn:ietf:params:oauth:token-type:access_token' \
   --data-urlencode 'grant_type=urn:ietf:params:oauth:grant-type:token-exchange'
   

   Note

   WSO2 Identity Server only copies the sub claim from the token received from the trusted token issuer to the exchanged WSO2 Identity Server token.

Upon successful execution, you will receive the exchanged token issued by WSO2 Identity Server.