[TYPO3-mvc] Set priviliges

[Dawid Pacholczyk]

Hello List,
  I`m wondering how to set some priviliges ?

For example I would like to enable edit or add action only for logged 
users or for users from some usergroup ?

I can set a bool flag in controller and pass it to fluid. But when user 
will invoke the url with action name manualy he will be able to add new 
record. How can I block it ?

Best regards,
Dawid Pacholczyk