Security

[minthaka]

Hi,
does anybody know how to disable booting into Linux. I mean I would put a password into Grub. Can I definitely refuse logging in without selecting an users profile. Cos when my son hits the Esc button it logs in. Not as root and not as an user. Is it possibile?
I hope I was clear. Once more. Can I lock the computer with a password to avoid any activity on it ?

[tvilkov]

try setting the password in the BIOS

[anomie]

BIOS password is fine unless he wants his kid to be able to boot to Windows (on a dual boot system).

If you only want to prevent booting to Linux, and not other OS, read here:
http://www.gnu.org/software/grub/man.../Security.html

Use password + lock for the grub Linux entry.

[benjamin20]

??? this brings a whole new light into the world of linux security. by rebooting anyone could just cat /etc/passwd and get all passwords. i think this grub password stuff should be activated by default by distros, as it not only effectivaly disables security but also shows passwords.

[anomie]

by rebooting anyone could just cat /etc/passwd and get all passwords

Password hashes are actually stored in /etc/shadow, and only root has read access to the file.

But there are lots of other ways to compromise your box if someone has physical access to it. (There is a long thread on this discussion somewhere, so I won't rehash it here.)