Html5 script for making text file and give cookie access

Hi. A very simple function / script. We link to various files for downloading on our html website. When a user clicks on a link, the server should look for a cookie. If the cookie is valid (30 min limit) they can download the file. If not they should be forced to write, name, number and contact info, verified fields. The information should be emailed to our data import adress as a ; separated text. The links are on multiple pages on the site (as text), so a popup with contact information needs to be on every page that has a download. Maybe as a php include file? Adress to file should be hidden behind script so that its harder to download without the cookie. Site is on apache.