OpenSSH GSoC Project

[Peter Lambrechtsen]

On Tue, Mar 24, 2009 at 12:30 PM, Jim Knoble <jmknoble at pobox.com> wrote:
> On 2009-03-23 16:05, Pavel Labath wrote:
>
> : So, what are the features we want a polished sftp to have?
>
> The best interactive terminal-based SFTP client i've used so far is LFTP
> <http://lftp.yar.ru/>, by opening an URL like 'sftp://remote-host'.
>
> : The only thing mentioned so far is the recursive up/down load, which
> : looks more like a thing for a two day hackfest than a all-summer-long
> : $4.5k operation.
>
> Perhaps i misunderstand, but i think the intent of the GSoC description
> is to make sftp(1) a potential replacement for scp(1), insofar as
> non-interactive invocation from the shell prompt is concerned.  Example:
>
>    scp -p -r ./some_dir remote-host:
>
> Currently, sftp(1) understands neither '-p' nor '-r'.  Obviously,
> sftp(1) currently has some conflicting options, and it will be necessary
> to balance compatibility with scp(1) against compatibilty with prior
> versions of sftp(1).
>
> It may be that the best way to do some of this would be the same way
> F-Secure's SSH does it:  use scp2(1), which would eventually completely
> replace scp(1).
>
> That said, i often use either rsync(1) or combinations of ssh(1) and
> tar(1) to do transfers from a shell command-line.
>
> : Features i would consider useful are:
> : - tab completion (both commands and filenames) - very useful, not difficult
>
> Tab completion is nice.  LFTP provides both local and remote filename
> completion, but remote completion can sometimes take awhile, so beware.
>
> : - transfer resume (thanks Iain Morgan, I almost forgot) - very useful,
> : not difficult
>
> Look at LFTP's interface for resuming ("continuing") a transfer.
>
> : - background transfer (possibly threads, or just fancy select() calls) -
> : useful, not very difficult
>
> Again, look at LFTP for ideas.
>

Few other nice to haves:

Transferring open files.  Such as a "tail -f" being able to copy a
open log file, even if it is displayed as zero bytes try reading the
file and seeing how far you can go.

Plus one other wishlist I had is "man-in-the-middle" scp / sftp.  ie
scp user at hostname1:/file user2 at hostname2:/destdir.  As I have a number
of areas where I have a DMZ server that can access two remote servers
in different zones, but the two servers cannot communicate with each
other, and I need to find a way to copy from one server to the other,
difficult if the DMZ server has a small amount of storage and you need
to copy a large file.