running a ftp server behind a proxy
 

I run my main computer1's internet through another computer2 in another building and connect to the internet through a socks 5 proxy installed on computer2. I want to run a ftp server on my main computer1 but I'm not sure how because this computer has the internet thru a socks 5 proxy. is there a way that I can run a ftp server behind a proxy or is there a way I can get the internet from the other computer2 besides socks proxy? like ssh or something?