Re: SCP under SSH2

[Thor Simon <tls%cs.stevens.edu@localhost>]

On Mon, Sep 12, 2005 at 09:11:01PM +1200, Peter Gutmann wrote:
> Jon Bright <jon%siliconcircus.com@localhost>
> >Claudio Robles wrote:
> >>  I have read all the drafts and found no mention to SCP.
> >
> >The protocol never got standardised (at least, never got standardised as scp
> >- and I don't believe it ever got standardised as rcp either).
> 
> Yup, you need to find someone else's source and read it to reverse-engineer
> the protocol details.  However before doing that, two questions:
> 
> 1. Why do you need to run scp under SSHv2?
> 2. If there's really some need for this, why not tunnel rcp over SSH?

FreSSH did #2.  It worked fine.  Whether you call that "running scp
under SSHvWhatever" is largely immaterial -- after all, with the
command line arguments bashed appropriately, 4.4BSD 'rcp' will talk
perfectly happily to OpenSSH 'scp'; the protocol is really the same.

There are legitimate reasons to not implement sftp -- it's a pig (let us
leave aside whether it is a necessary pig or a useful pig; it is still a
pig).  There's nothing inherently wrong with rcp except that you have to
be careful about the server-side globbing -- but a small embedded
implementation would be entirely free to omit globbing entirely, and then
the problem disappears right along with it.  

It's unfortunate that rcp is not documented -- and largely my fault,
since I said I'd do it one of the first times this came up in the WG
but never produced the document.

Thor