Force SSL to be active only at checkout page of a Bitnami Magento Instance

Hi, I need someone to force ssl to be active only at login -register -cart and checkout [login to view URL] magento website is a bitnami image . -It CAN NOT be done from Magento admin [login to view URL] this option is out !!! (already tried) Possibly .htaccess is the right way to solve this task (I am not sure if there is other way). Currently https:// ssl is active and enabled throughout the website! This is a 1 hour project for those who are truely capable of solving this problem.