php files sharing with user permissions that keeps ftp upload structure of folders and files

We are looking a solution where we can upload files to a linux server via sftp and for the file sharing platform to then see all files and folders we upload

then we need to be able to

• set ow开发者_开发知识库nership of files and folders so only certain users can download files
• keep structure of all folders and files
• share files folders with more than 1 user

we would appreciate any recommendations of solutions that are as affordable as possible if not free :)

There are tons of these types of apps floating around. Try google.

http://pfn.sourceforge.net/

http://www.opendocman.com/