Re: pruning cruft in /etc/passwd and /etc/group
--- Andrew Schulman <andrex@alumni.utexas.net> wrote:
> Over years of testing software, my /etc/passwd and /etc/group files are
> littered with leftover junk. Here are some entries in /etc/passwd which
> don't correspond to any actual or useful virtual users that I'm aware
> of:
>
> backup bin daemon games irc list lp mail man messagebus operator
> proxy sync sys uucp
You're wrong. They're used by certain daemons. I am not going to list
every entry against the likely candidate, either. Suffice it to say that
they're part of tradition, and at a lower level, convey the underlying
permissions about how a lot of applications operate.
> Here's a list of questionable entries in /etc/group:
>
> adm audio backup bin daemon dialout dip disk fax floppy games irc kmem
It's a matter of convention. "adm" as group ownership is used on a number
of directories in /var. "audio", is used on /dev'ice nodes for sound
applications, "dialout", by the same token as for "audio" - but used on
modem devices. "disk" is used for harddrives and other devices.
> As a general security measure, I want to prune the useless entries from
> these files (and /etc/shadow too, of course). The problem is to be sure
> that before I remove an entry, it's not going to make bad things happen.
If you do that, you will break all your permissions on your system at a
fundemental level! Furthermore, I can't quite see where your argument or
concern about security stems from. These are not "users" that login.
They're static -- defined by the system (and fairly common across all
Linux variants, and Unixes that I know of, bar one or two exceptions). The
idea is flawed, and without reason.
[..snip..]
-- Thomas Adam
=====
"The Linux Weekend Mechanic" -- http://linuxgazette.net
"TAG Editor" -- http://linuxgazette.net
"<shrug> We'll just save up your sins, Thomas, and punish
you for all of them at once when you get better. The
experience will probably kill you. :)"
-- Benjamin A. Okopnik (Linux Gazette Technical Editor)
___________________________________________________________
ALL-NEW Yahoo! Messenger - all new features - even more fun! http://uk.messenger.yahoo.com
Reply to: