User authentication in direct mode

In direct mode, user authentication involves defining a DB Sync user record, registering the user ID and password (if applicable), with the password encrypted server-side during the process.

In direct mode (when dbsync_source.use_gas == FALSE), define a DB Sync user record, and register the user id (+ password if there is one defined):
  DEFINE user_ident dbsync_core.t_user_ident
  LET user_ident.user_id = user_id
  LET user_ident.user_auth = password
  CALL dbsync_app.register_dbsync_user(user_ident)

The user password is provided in clear; it will be encrypted server-side.