code: func Serve(p ca.Provider) {
  	plugin.Serve(&plugin.ServeConfig{
  		HandshakeConfig: handshakeConfig,
  		Plugins: map[string]plugin.Plugin{
  			Name: &ProviderPlugin{Impl: p},
  		},
  	})
  }
docs: // Serve serves a CA plugin. This function never returns and should be the
  // final function called in the main function of the plugin.