[Techtalk] sharing files - ssh and ftp

[Rasjid Wilcox]

Kim,

So what you want is that users are unable to (easily) discover the names of 
other users on the system.  For what you want, my SFTP solution will not 
work, since users can still traverse up into /home and see the names of other 
users.

I suspect that this is very hard if you are giving someone shell access, but 
should be possible if you are just giving FTP access.  So, I would agree with 
Maria, you are really after a ftp-server, and having spent a little time 
configuring proftpd, I would recommend it as being easy to configure.  I 
believe it also seen as fairly secure whilst still maintaining flexability.

The proftpd site has lots of good info, including a doc on configuring FTP 
over SSH.  

The key question is whether your ftp server is behind a firewall doing NAT or 
has a public IP address.

>From a quick look at the docs, if your server has its own public IP address, 
then you should be able to set up SSL/TLS support with proftpd.  I think it 
gets much harder if your ftp server is behind a NAT firewall.  In this case, 
you may need an ftp proxy, but ftp proxies that support ssl/tls seem to be a 
bit thin on the ground.

A good place to start of the whole SSL/TLS for FTP thing is 
http://www.ford-hutchinson.com/~fh-1-pfh/ftps-ext.html.  Also see 
http://www.castaglia.org/proftpd/doc/contrib/ProFTPD-mini-HOWTO-TLS.html

I spent quite a lot of time looking at all this a few years ago, and came up 
with a SSH / Ftp Proxy / FTP server solution.  However it is a little complex 
for the average user, and due to limitations in Putty was somewhat unstable 
on Windows.  The whole TLS FTP thing seems to have progressed somewhat since 
then, and is probably the way to go, but I can send you details (offlist) of 
what I did if you like.

Cheers,

Rasjid.

-- 

Rasjid Wilcox
Canberra, Australia  UTC + 10
http://www.openminddev.net