Isaac Wagner-Muns wrote:
> I'm trying to set up a small shell account server for students at my =20
> school, and it seems to be quite a vast undertaking, mostly because =20
> of the security issues brought up by letting semi-anonymous people =20
> access my machine.=20

I'm no security expert, but I'll answer anyway because you'll be lucky to
have a real expert answer. =20

It's a matter of trust and degree.  There was a thread here just the other
day discussing what to do if someone you didn't know gained access to the
machine i.e., reinstall from known good media.  If your students are
*trying* to subvert the machine, you probably don't want to give them
accounts in the first place. =20

That said, if I were in your shoes, I wouldn't hesitate to add accounts
with useradd(1) and hand them the keys.  If the machine faces the
Internet, though, I would discuss password selection and try to enforce
access by shared keys via ssh only, if that's feasible.=20

> Is having publicly runnable shell scripts insecure?=20

Not as such.  Shell scripts ship with NetBSD in /usr/bin.  What you want
to avoid is shell scripts that are setuid and owned by root.  That's known
to be unsecurable. =20

Undoubtedly there are other considerations, but that's what springs to
mind.=A0=20

Regards,=20

--jkl