I'm looking for a web platform to put company files at. My requirements are:

• should be accessible via a browser
• should be open source
• must be installable (dropbox is a no-go)
• must have an option to put a access time limit on a file
• must perform garbage collection automatically after a file expires
• must be able to mark files as public or private
• an option to protect a file via a pin-code for users without accounts in the system would be nice to have

The problem is I don't even know what to search for - all my googling results in either complete groupware solutions or p2p file sharing software. If such a thing doesn't exist, please don't hestitate to say so, so I can crawl to a corner and cry myself to sleep.

TIA