Skip site navigation (1)Skip section navigation (2)
Date:      Mon, 03 Jul 2000 14:06:48 -0700 (PDT)
From:      John Baldwin <jhb@FreeBSD.ORG>
To:        Alex Popa <razor@ldc.ro>
Cc:        freebsd-security@FreeBSD.ORG
Subject:   RE: securing the boot process (again?!?)
Message-ID:  <200007032106.OAA36912@john.baldwin.cx>
In-Reply-To: <20000703115320.A341@ldc.ro>

next in thread | previous in thread | raw e-mail | index | archive | help

On 03-Jul-00 Alex Popa wrote:
> I have been trying to secure (a bit) the boot process of a 4.0-STABLE
> machine that is located in a public place.
> 
> I need to use the floppy disk, but if I disable it from the BIOS I get
> no access to it under FreeBSD.  So I set the boot sequence to "C only"
> but if I press space while the initial hyphen is displayed i get a
> prompt with no password being requested. (Note I have set a password
> in /boot/loader.conf, and set the console to "insecure" in /etc/ttys)
> 
> The problem is I can boot any kernel or loader, including a kernel off
> the floppy drive [just type fd(0,a)/evilkernel at the prompt].  From
> there to a setuid(12345) that yields uid=0 (patched kernel, remember?)
> is just a small step.  Any ideas for further improvement of the boot
> process security?

Umm, well.  You can try hacking boot2 to require a password, but
usually if someone has physical access to the machine, it's close
to being all over to begin with.  You could also hack boot2 to just
always load /boot/loader and never allow for a prompt if you wish.

> Note: I have used the "Dangerously dedicated" option when installing.

Ugh, well, you can't ever use boot0 or any other boot managers. :P

> Thanks alot,
>       Alex.

-- 

John Baldwin <jhb@FreeBSD.org> -- http://www.FreeBSD.org/~jhb/
PGP Key: http://www.cslab.vt.edu/~jobaldwi/pgpkey.asc
"Power Users Use the Power to Serve!"  -  http://www.FreeBSD.org/


To Unsubscribe: send mail to majordomo@FreeBSD.org
with "unsubscribe freebsd-security" in the body of the message




Want to link to this message? Use this URL: <https://mail-archive.FreeBSD.org/cgi/mid.cgi?200007032106.OAA36912>