Subject: Re: [linux-security] Re: You wouldn't believe it...

From: [email-masked] (Kai Henningsen)
Date: 11 Jul 1996 20:14:00 +0200

>From linux-security, with some thoughts about configuring packages and  
telling the user (sysadmin) about it.

We've already talked about similar things. Maybe we should think some more  
about this.

[email-masked] (John Henders)  wrote on 10.07.96 in <[email-masked]>:

> Jon Lewis writes:
>
> > This is something I meant to say something about...but kept forgetting.
> > There's this box I installed very nearly all of Red Hat 3.0.3 on to get a
> > feel for Red Hat and see just how much I'd hate it.  Maybe I just haven't
> > gotten to know it well enough...but I greatly prefer my hacked up
> > slackware based boxes.  Anyway, one day a co-worker brings in his
> > notebook with pcmcia ethernet, and asks me whats up with this Windows
> > server on our network.  "What windows server?"  It was then that I found
> > that by default, Red Hat 3.0.3 setup Samba for me and ran it with /tmp
> > world rw.  I still don't know Samba, but I assume this is the section of
> > config file responsible:
> >
> > [tmp]
> >    comment = Temporary file space
> >    path = /tmp
> >    read only = no
> >    public = yes
> >
> > On a small box such as this one, where the root fs is _the_ fs, a world
> > writable (no account needed) exported directory could be a very bad thing.
>
> Only if there's a bug in samba that allows you to get out of the
> directory that is exported, as there was with the NT implementation.
>
> I think this is the result of a different philosophy than Slackware more
> than anything else. With Redhat, the assumption seems to be that if you
> ask for a package to be installed it will be configured as well, where
> as Slackware (or at least the last version I installed) just installs
> the package and leaves you to figure out how to configure it. Debian
> seems to follow the Redhat philosophy as well. If you install
> netatalk, for instance, it configures it to allow users to mount this
> home directory.
>
> Where both packages fall down, redhat's rpm installed the most, IMHO, is
> that they fail to tell you very little about what they've done. rpm
> --install package is comeletely silent, and the -v verbose flag is not
> much better. Debian fares much better in this regard, but I'd still
> think more info on the package should be presented somehow.
>
> The problem is even worse when installing a whole distribution, as in my
> experience, no one sticks around to watch the messages printed on a
> large install. Perhaps if the installers had info sheets for each
> package, on a bulk install they could save them all to disk and then
> mail the whole thing to root after installation.

MfG Kai

---

From: "James A. Robinson" <[email-masked]>
Date: Fri, 12 Jul 1996 23:17:39 -0400

> We've already talked about similar things. Maybe we should think some more  

Well, I'll just thrown in the opinion that we shouldn't enable any
uneeded network services by default -- we should ask first, and if
possible we should move the configuration scripts into /usr/sbin or
something -- so that people can redo it whenever they want.

For example, it would be really nice for the script that runs on the
base disks and setups up the network were available as a netconfig
script, just like there is bindconfig and smailconfig available.

We also have never gotten the dpkg functions for "never ask me any
questions, just do this" (within reason).  I can't imagine what people
who want to install and ugprade hundereds of machines think of
Debian's questions -- they probably don't have the time or patience to
sit there and watch for the prompts.  Is there a way around this?  I
can't think of any off the top of my head -- perhaps an expect script
and some standardized format for config scripts?  Like "do you wish to
setup blah now [Y/n]?"

> > > world rw.  I still don't know Samba, but I assume this is the section of

Ack!  That is horrible behaviour!

> > netatalk, for instance, it configures it to allow users to mount this

I've never installed netatalk, but if it does this without asking, it
sounds like a problem to me.

Jim

---

From: Klee Dienes <[email-masked]>
Date: Sat, 13 Jul 1996 23:50:00 -0700

>>> [...] If you install netatalk, for instance, it
>>> configures it to allow users to mount this home directory.

> sounds like a problem to me.

If not configured by the installer, the netatalk package by default
makes each user's home directory available to that user if they
connect to the fileserver with their username and password.

Although I'd argue that this isn't a significant security violation
(given that the base distribution already allows remote access using
the same username and password via rlogin), I'd be willing to take it
out as a matter of principle unless someone objects.

---

From: Ian Jackson <[email-masked]>
Date: Tue, 16 Jul 96 14:21 BST

Klee Dienes writes ("Re: [linux-security] Re: You wouldn't believe it... "):
...
> connect to the fileserver with their username and password.

That's reasonable.

> out as a matter of principle unless someone objects.

Object !

I may be a security paranoid type, but it is futile to try to make
things more secure by failing to set them up in a useful way when they
are installed.

Our default settings should be secure but useful.  If people don't
trust the security in a program they are free not to install it at
all.

Ian.