Problem running 4.2 rdump from a workstation

[Greg Couch%CGL]

> Sorry if this is common knowledge, but I haven't seen it discussed before...
> 
> If you have a network of workstaions and a VAX, you probably don't want to 
> generally grant superuser priviliges on the VAX to everyone running as such on
> a workstation, and accordingly the validation routines skip /etc/hosts.equiv 
> when you try to become superuser on the remote host. The problem with such a 
> setup is that when you use e.g. 'rdump' from the workstation, you'll normally 
> have to be superuser, meaning that you can't access the VAX at all!
> 
> One workaround would be to have a userid with another name than "root", which
> would be superuser on the workstation but not on the VAX. However, 'rdump' has
> "root" hardcoded, and doesn't care what the current userid is! Is there a
> reason for this? Are there any other (better?) solutions to this problem?
> 
> I suppose what one would really want is for "root" on a host listed in
> /etc/hosts.equiv but not in /.rhosts to be allowed to do rdump (rsh, rcp...)
> with a generic "other" userid, i.e. with no particular access rights...
> 
> Per Hedeland   {decvax,philabs,seismo}!mcvax!enea!erix!per  or  per at erix.UUCP

We had a similar problem here, when some of the other labs' vaxen tape drives
failed and we didn't feel like giving them root access to do dumps over the
ethernet to our tape drive.  Here's a modification to src/etc/dump/dumprmt.c
which does the right thing by allowing the rcp syntax (machine.user:file) to
be used to specify the remote tape drive.  As this isn't really a bug, but an
enhancement, this hasn't been sent to Berkeley.

					- Greg Couch
					ucbvax!ucsfcgl!gregc
					ucsfcgl!gregc at Berkeley.Arpa
-----
RCS file: RCS/dumprmt.c,v
retrieving revision 1.1
diff  -r1.1 dumprmt.c
18a18
> char	*rmtpeeruser;
22a23
> 	char	*index();
24a26,29
> 	if ((rmtpeeruser = index(host, '.')) == NULL)
> 		rmtpeeruser = "root";
> 	else
> 		*rmtpeeruser++ = '\0';
49c54
< 	rmtape = rcmd(&rmtpeer, sp->s_port, "root", "root", "/etc/rmt", 0);
---
> 	rmtape = rcmd(&rmtpeer, sp->s_port, "root", rmtpeeruser, "/etc/rmt", 0);