Article View: gnu.bash.bug
Article #890Re: login should be a builtin
From: Dan Jacobson
Date: Thu, 13 Aug 1992 15:43
Date: Thu, 13 Aug 1992 15:43
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3967 bytes
>>>>> On Sat, 8 Aug 1992 11:53:07 GMT, jch+@cs.cmu.edu (Jonathan
>>>>> Hardwick) said:
JH> danj1@ihspa.ATt.COM (Dan Jacobson) writes
>>>>>>>>>>>>>>>>>>^Like, yo, yo, gnu list maintainers, your e-mail to
news gateway consistently downcases this letter in the "From:" header.
> login should be a builtin, because if jimmy, used to some other leading
> brands of shell, does
> bash$ login jenny
> as he turns over the terminal to jenny, and then later jenny logs out
> and walks away, jimmy's bash will be sitting there, so some baddie
> will take advantage of it
JH> [ deleted ]
> Plus it's unreasonable to expect jimmy to memorize "'exec login' when
> under bash".
JH> It's unreasonable for jenny not to expect a trojan horse when jimmy types
JH> bash$ login jenny
JH> at his terminal and then says "there you go, it's all yours". Both
JH> jimmy and jenny appear to be in dire need of a basic computer security
JH> course. Even something as simple as:
JH> 1. "always log out when you leave your terminal"
JH> 2. "never log in unless you're sure a trojan isn't running"**
JH> would do. If they can't even master these basic points, they have a
JH> whole heap more trouble to worry about than login not being a builtin
JH> in some shells.
But even if jimmy & jenny are best of trusting friends, the problem is
the 3rd party baddie...
JH> Jonathan H.
JH> ** For arbitrary definitions of "sure".
>>>>> On Sat, 8 Aug 1992 23:47:23 GMT, friedman@gnu.ai.mit.edu (Noah Friedman) said:
NF> In article <1992Aug7Fr000428a.danj1@ihspa.att.com> danj1@ihspa.ATt.COM (Dan Jacobson) writes:
>login should be a builtin, because if jimmy, used to some other leading
>brands of shell, does
>bash$ login jenny
>as he turns over the terminal to jenny, and then later jenny logs out
>and walks away, jimmy's bash will be sitting there, so some baddie
>will take advantage of it, and then the whole school will hear some
>rumor that bash is a security hazard.
NF> I used to feel this way too, but lately I've decided I don't like for
NF> shells to be that clever. It's even worse for some shells to recognize
NF> "newgrp" and do the same thing they do for login. It's a misfeature in
NF> those shells.
Thanks for reminding me about that massive drag "newgrp" crap in some
shells, I hereby rescind [withdraw] my original complaint. One less
special twist for "security" is one more step towards a cleaner shell.
> Plus, two out of three selected
>big name shells do it:
NF> "If a million people do a foolish thing, it is still a foolish thing." :-)
>Plus it's unreasonable to expect jimmy to memorize "'exec login' when
>under bash".
NF> If it's really that much of a problem, then I'd suggest putting the
NF> following in /etc/profile:
NF> if [ -n "${PS1}" -a -n "${BASH_VERSION}" ]; then
NF> alias login='exec login'
NF> fi
Probably best put in a specific parinoid person's .profile.
NF> But think about whether you really want to do this, instead of doing the
NF> Right Thing and getting users to learn about how the shell behaves in the
NF> first place. If the users are lazy even after that, then they can make
NF> their own aliases.
Cool, I agree. [Like, wowsky... I did a 180 degree viewpoint change.]
--
danj1@ihspa.att.com (Dan Jacobson) Naperville IL USA
+17089796364 Chinese~{;}5$Da~}Ji1Dan1ni2
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Newsgroups: gnu.bash.bug Path: arc1-ca.pugleaf.net!sparky!uunet!convex!darwin.sura.net!zaphod.mps.ohio-state.edu!cis.ohio-state.edu!ihspa.ATt.COM!danj1 From: danj1@ihspa.ATt.COM (Dan Jacobson) Subject: Re: login should be a builtin Message-ID: <1992Aug13Th114348a.danj1@ihspa.att.com> Sender: gnulists@ai.mit.edu Organization: GNUs Not Usenet References: <1992Aug7Fr000428a.danj1@ihspa.att.com> Distribution: gnu Date: Thu, 13 Aug 1992 15:43:00 GMT Approved: bug-bash@prep.ai.mit.edu Lines: 84