Forcing a transfer to be one-way from the daemon side?
lanclos at ucolick.org
Wed May 7 16:31:11 GMT 2008
danm at prime.gushi.org wrote:
> I'm trying to set up a secure way to back up a system as root, with rsync
> (assume we don't want to kill the bandwidth and want a "snapshot" system
> for developers in a way that makes dump, tar, etc impractical.
> We've got an ssh key relationship set up and we can force the command to
> be rsync --daemon.
I set up a similar system, except that I used an ssh agent rather than a
simple key relationship. I hope this diagram makes sense:
\ \-> authorized_keys includes server_id_dsa.pub
\ \-> server_id_dsa attached
\--> ssh to client machine
/ \-> authorized_keys includes server_id_dsa.pub,
rsync to server <-/ which only runs rsync script
This way, the client machine can only rsync back data when the ssh agent
is present, because the server only allows in connections for its *own*
key, not any key that is stored on the client filesystem.
If you want to make this somewhat more secure, set it up in such a way
that the client machine cannot write to the rsync script-- in our case,
the client machines access the rsync script from a read-only nfs partition.
More information about the rsync