Call Back Asterisk VOIP

Simple Project for Asterisk Guru 1- Place a call to Asterisk (sip local number), detect my clid and Hang UP. 2- Detect to know is a valid clid (look a the mysql database for find user with that clid) 3- Call Back that number with a dialtone and the user enter a phone number 4- Verification in the DB; that phone numbers is Ok to dial 5- If is OK ; Make the call Also: Web Page in PHP for insert informations for the application