Alternative Project

[Logan P. <lo...@so...>]

To those needing the functionality of rssh, I needed an sftp server
which would *only* allow file access via sftp, and *only* to files
within a virtual filesystem root.  Not finding anything which easily
satisfied my requirements, and knowing that trying to sufficiently
blacklist a permissive-by-default system like openssh is futile, I
wrote my own, on top of python's Twisted module.  It requires
whitelisting (and implementing) features that you want, with no
ability to do things you don't give it (the public repo lacks any
shell support, for example, though I have added one in some
deployments), and quite primitive (silently ignores file attribute
setting, doesn't support making symlinks or extensions), but it *does*
work quite nicely for sftp / sshfs use.  As it is implemented in pure
python, the performance is somewhere around 10% of openssh, so don't
expect it to handle heavy loads well.  By default it only supports rsa
keys, but I have used it with ecdsa.

In general, twisted's protocol support is excellent, so with a bit of
python knowledge you can adapt it to nearly anything you want.  scp
and rsync are probably out of easy reach, as they normally run a
client program on the destination, which would either break the
sandbox or have to be dummied within the python virtual filesystem.
The latter is the *correct* approach, but is likely more work than is
worth doing.  I have used it with git by first mounting via sshfs;
native git+ssh support is probably possible, but again would require a
fair bit of work.

Anyway, you can find the code at
https://github.com/lp-programming/WorkflowUpload/
As the project name implies, I use it for uploading github build
artifacts to offsite storage.

Regards,
Logan