Is your feature request related to a problem? Please describe.

Support Cumulocity IoT basic auth registration process to provide an upgrade path for existing customers whom use (legacy) SmartREST 1.0 (which is not supported when using cert based authentication)

Background

Existing customers with existing agents would like to take advantage of thin-edge.io and slowing migrate custom components. However these agents sometimes use SmartREST 1.0 which is incompatible with the cert-based device credentials (the default authentication used by thin-edge.io).

Describe the solution you'd like

Add support for basic auth device credentials for the Cumulocity IoT mapper so that devices can be registered following the Device Registration mechanism.

Implementation details

When using basic auth device credentials

• Do not store Cumulocity device credentials in the tedge.toml as these should be protected like a certificate (and not mixed with other non-sensitive configuration)
• c8y proxy must use a Basic Auth ,e.g. Authorization: Basic <base64(username:password)>
• Don't subscribe to s/uat and s/dat topics as they are only supported when using cert-based device credentials and errors will be posted to s/e if they are subscribed to

Open questions

• How to test an MQTT connection as the JWT topics are not available - Should a very basic SmartREST 1.0 template be used instead?

Implementation plan

The feature implementation can be broken into the following parts:

1. Support new configuration sets the registration mode (e.g. use basic auth, or device credentials/jwt)
   • Activate the basic mode via tedge config set c8y.registration_mode "basic"
   • Allow a username and password to be set via the command line and store in a new file (owned by tedge and with 600 permissions)
2. Update components to support using either Bearer or Basic auth for communication with Cumulocity IoT REST API (see below for a list of components)
3. Support registration of SmartREST 1.0 templates via a new tedge config tedge config set c8y.smartrest1.templates "template1,template2"
4. Support the Cumulocity IoT device registration process using the Cumulocity IoT bootstrap credentials when calling tedge connect and the "basic" registration mode is active (there are some UX aspects here to consider).

Describe alternatives you've considered

Additional context

Check list for components that require an update of the Authorization header mechanisms:

• Cumulocity IoT proxy (e.g. the 127.0.0.1:8001/c8y service)
• c8y-remote-access-plugin supports basic auth
• tedge-mapper
• bridges support both bearer and basic auth
  • mosquitto bridge
  • built-in bridge