Share 'Using unsupported OAuth provider'

Is it possible to create a custom OAuth provider?  Specifically, we are working with Cisco (https://cloudsso.cisco.com/as/token.oauth2). We have a requirement to integrate with a Cisco soap server which uses OAuth2 for authentication. We are using a Service Connector to send a message to the SOAP service, but we need to write custom code in a business process to authenticate with their Cisco OAut…