The purpose of the Daily Scrum is to inspect the progress of the Development Team toward the Sprint Goal, to discuss this progress and to decide what to do next until the next Daily Scrum. If there is anything that impedes the Development Team from achieving the Sprint Goal, the Development Team decides how to deal with this impediment and (if needed) re-plan the Development Teams work to achieve the Sprint Goal. The result of the Daily Scrum should be an updated Sprint Backlog to achieve the Sprint Goal.
The development team is a self-organizing team and their members are the only ones participating in the Daily Scrum. The role of the Scrum Master concerning the Daily Scrum is to teach the Development Team to keep the Daily Scrum within the timebox of 15 minutes.