Trying OpenSSH in Debian Etch ... plus thoughts on security, sudo and nano vs. vi

| | Comments (6) |

I did a Debian Etch install on one of my test machine drives recently, and today I added the openssh-server package so I could play around with PuTTY and Xming.

Once I installed openssh-server (I used Synaptic, in case you were wondering), using PuTTY to start the connection, I was asked whether or not I expected the encryption key to change (I was, since this is the Debian install, not OpenBSD, which I've been using until now).

One bonus of using this Debian Etch install: The OpenBSD drive is noisy, which probably means it's gonna go. The drive on which I installed Etch is much quieter. I probably need to get some newer, bigger drives ... or a whole new test box, but that's another story for another time.

Quirks in Debian Etch with openssh-server: I can run X apps, no problem. When I run:

$ nautilus &

... I get a huge window with the entire GNOME desktop, minus the toolbars. And I can't close that window -- Xming won't let me, I think. X-ing it out doesn't work. I had to kill the process in my PuTTY terminal. (Note: $ startx & does not work ...)

Speaking of security: OpenBSD is known for its security above all else. Here's how using openssl openssh (which was created by the OpenBSD team) differs -- at my lowly level, anyway -- between OpenBSD and Debian Etch:

In OpenBSD: The sshd server is included in the standard install. But it can't be used until rootly powers are used to implement it. Running X over ssh is not allowed until the appropriate configuration changes are made. But root logins are allowed over ssh by default; the administrator, however, can choose to block root login (which I did).

In Debian: Debian installs without the ssh server installed. So without the administrator specifically installing openssh-server, nobody can ssh into the box. But once that package is installed, Debian automatically allows ssh logins -- and X logins as well. As with OpenBSD in its default state, root logins are permitted over ssh until that feature is turned off in /etc/sshd_config.

I don't understand all the lines in sshd_config, but I probably should get better acquainted with each and every one of them.

Speed? It could be the fact that this Debian Etch box has the GNOME desktop, and I've been running OpenBSD either from the console or the default Fvwm window manager, but everything happens a lot faster with the OpenBSD install (hardware is the same for both). I could modify Debian to boot to a console instead of GDM, and that might speed it up a bit (memory is 256 MB), but whatever the reason, thus far OpenBSD is a bit smoother. (Later, things seemed to run a bit better when I didn't log in on the Debian box and hence didn't have GNOME running).

More on security: If this box wasn't just something for me to play with on the local network, the stakes would be a lot higher. I suppose not having sshd is pretty good security when compared to having sshd installed but not enabled. And I also suppose that installing sshd (openssh-server) means that you want to actually use it. But in the case of both OpenBSD and Debian, I wonder why root logins over SSH are enabled by default. If anything, I'd expect OpenBSD to disallow them until the administrator of the box decides to turn that feature on.

And since you can always use su or sudo (Ubuntu has conditioned me to like sudo, and I always add myself to the sudoers list with visudo, there's really no reason for a root login over ssh.

Side note: Debian doesn't automatically add the primary user to the sudoers list, something I always do because on many occasions I'd rather use sudo than su.

Ubuntu, by default, disables root logins entirely and only offers sudo. It makes setting root's crontab a pain in the ass. I use sudo -i crontab -e to get into root's crontab in Ubuntu.

Side note to a side note: While I can fake my way around vi, I like it when nano is the default editor and crontab -e brings up nano instead of vi. The one thing I don't like about nano is that when you wrap text, actually linefeeds are inserted. At least in vi you can have the text break in the middle of a word without turning word wrap on (although you are able to do so if you want wrapped text). The one thing I like in X editors is the ability for text to look wrapped without actually being wrapped.

6 Comments

Nat said:

Root logins are allowed by default on OpenBSD because there is no other account by default. This is a part of how things have always been, in order to keep the install simple and upgrades easy. man afterboot some time, OpenBSD tells you to on your first boot, it also tells you to use sudo and not su.

OpenBSD and OpenSSL are completely unrelated projects, OpenBSD does OpenSSH, but not OpenSSL. That is a widely held misconception, one that agrivates the hell out of OpenSSL developers.

Martin Hooper said:

$nano -w

Disables wordwrap for when you are editing config files or files with long lines.

I'm talking about OpenSSH, and more specifically the openssh-server package in Debian. And it is the OpenSSH that comes from OpenBSD.

What I want to do is enable word wrap, then disable it and make all the extra linefeeds go away.

Chris Lees said:

nautilus --no-desktop.

That should run Nautilus but not manage the desktop.

miksuh said:

Ubuntu style to use sudo is not secure, no matter if ubuntu guys try to sa. And that's not how sudo was meant to be used.

Ubuntu gives full root access to that default sudo-user. That line in Ubuntu /etc/sudoers does not set any restrictions on it what that sudo-user can do. It gives full root access. that user can execute any command which needs root rights, and that's not how sudo was meant to be used.

In Debian users do not have any sudo rights by default. Sudo was originally meant to be used so that root can give user right to use specific command(s) which need root rights. user could then use just those commands, and not any command which root can use. Sudo was not meant to be used as a full root replacement when user can execute any command as a root.

Leave a comment

Tech Talk column

Steven Rosenberg's weekly Tech Talk column, which appears Saturdays in the Los Angeles Daily News, is now available on the Daily News Technology page.

About this blog

New ways to sign in to comment: I just added the ability for prospective commenters on this blog to sign in using their AOL, Yahoo! and Wordpress.com accounts (for the past 200 posts anyway ... more than that will take an extensive, middle-of-the-night rebuild). That's in addition to the other sign-in choices, which include starting a Movable Type account on this blog, Typekey, OpenID, Live Journal and Vox. If you have trouble getting your Movable Type account verified, or any of the other sign-in options are not working properly, please e-mail me. With these added ways of signing in, there's more reason than ever for you to make a comment (or several!).




Steven Rosenberg aims to learn what he does not know. He writes about it here.



About this Entry

This page contains a single entry by Steven Rosenberg published on March 4, 2008 11:30 AM.

Debian Lenny, FreeBSD 7, OpenBSD and silencing CPU fans was the previous entry in this blog.

ZDNet gets a facelift, and I don't like it is the next entry in this blog.

Find recent content on the main index or look in the archives to find all content.

Recent Comments

miksuh on Trying OpenSSH in Debian Etch ... plus thoughts on security, sudo and nano vs. vi: Ubuntu style to use sudo is not secure, no matter if ubuntu guys try t ...

Chris Lees on Trying OpenSSH in Debian Etch ... plus thoughts on security, sudo and nano vs. vi: nautilus --no-desktop. That should run Nautilus but not manage the de ...

Steven Rosenberg on Trying OpenSSH in Debian Etch ... plus thoughts on security, sudo and nano vs. vi: What I want to do is enable word wrap, then disable it and make all th ...

Steven Rosenberg on Trying OpenSSH in Debian Etch ... plus thoughts on security, sudo and nano vs. vi: I'm talking about OpenSSH, and more specifically the openssh-server pa ...

Martin Hooper on Trying OpenSSH in Debian Etch ... plus thoughts on security, sudo and nano vs. vi: $nano -w Disables wordwrap for when you are editing config files or ...

Nat on Trying OpenSSH in Debian Etch ... plus thoughts on security, sudo and nano vs. vi: Root logins are allowed by default on OpenBSD because there is no othe ...

Powered by Movable Type 4.25

LXer

Links

Daily News technology
LXer
Distrowatch
Linus' Blog
David Pogue
BoingBoing
Linux Today
TuxRadar
Linux.com
Linux Planet
The Open Road
Linux Outlaws podcast
Dan Lynch
Fabian Scherschel
The VAR Guy
Larry the Free Software Guy
Chess Griffin
Linux Reality podcast
Desktop Linux
Practical Technology
Linux Devices
ZDNet
ZDNet U.K.
iTWire
CNet News
TechCrunch
The Register
Ars Technica
Reg Developer
Computerworld
Computerworld blogs
Steven J. Vaughan-Nichols at Computerworld
Debian
Planet Debian
Debian Forums
Debian News
debianHELP
debiantutorials.org
The Debian User
Wolfgang Lonien
Debian-News.net
Debian Administration
Debian Admin
Debian Weather
Ubuntu
Xubuntu
Kubuntu
Edubuntu
Gobuntu
Planet Ubuntu
Ubuntu Forums
Ubuntu Geek
Works With U
Dustin Kirkland
Ubuntu UK Podcast
Popey
gNewSense
CrunchBang Linux
OpenBSD
OpenBSD Journal
OpenBSD Ports
OpenBSD 101
Planet.OpenBSD.nu
jggimi's OpenBSD live CD
DaemonForums
BSDanywhere
Marc Balmer
Denny's OpenBSD blog
Polarwave's OpenBSD Tips and Tricks
Binary Updates for OpenBSD
Puppy Linux
Damn Small Linux
Tiny Core Linux
PCLinuxOS
Mandriva
Red Hat
Red Hat News
Red Hat Blogs
Red Hat: Truth Happens
Red Hat Magazine
CentOS
Planet CentOS
Fedora
Slackware
Slackbuilds
Robby's Slackware Packages
Slackblogs
dropline GNOME for Slackware
GNOME Slackbuild
GWARE - GNOME for Slackware
Wolvix
Zenwalk Linux
Vector Linux
Slax
Splack Linux — Slackware for Sparc
Nonux
How to Forge
marc.info BSD and Linux mailing list archive
FreeBSD
FreeBSD, the Unknown Giant
A Year in the Life of a BSD Guru
NetBSD
PC-BSD
DesktopBSD
DragonFlyBSD
DragonFlyBSD Digest
DesktopBSD
BSD Talk podcast
OpenSolaris
MilaX
BeleniX
DeLi Linux
Linux Loop
Electronista
Engadget
Gizmodo

Advertisement

Other blogs

Johnson Update in Inside USC with Scott Wolf
Has Bynum outgrown Kareem? in Inside the Lakers
Can the Angels just get to the end of this thing without an injury? in Farther Off the Wall
Neuheisel On: in Inside UCLA with Jon Gold
U.S. Roster for Final Two WCQ Announced in 100 Percent Soccer