I'm looking for an open source (language does not matter) web application that lets me make downloads available to users. I would like to be able to have some downloads be available to all users, while some downloads are only visible to certain users. Ideally, each download can have a description that the user can view prior to downloading and a customer could view their available downloads simply by providing their email address without requiring a full login.
Things I have considered include a wiki where each page contains a download but that lacks the access control I would like to have. A download manager like ownCloud doesn't really allow for describing files before download.
Appreciate any suggestions!