by Is there any good place to find comprehensive information
about the different system-users (adm,lp,sync,halt)
and system-groups (bin,daemon,wheel,kmem)?
I'm looking for information about:
-what files/directories/devices should be owned by a
particular user and/or group.
-what programms should be SUID or SGID to a
particular user and/or group.
-what processess should be run on behalf of a
specific system-user.
-which system- and/or normal-users should belong
which groups (if any).
-when and *how* are some users (like sync and halt)
used (I actually get the "when", but how about
the *why*).
-the use of certain users and groups (like wheel --
I belive users allowed to su is supposed to be
meber of it, but how is it to be used correctly?).
---
I do see the purpose of the users and groups for
differenting the different types of files and for
running processes with as little privlige as possible.
That a program needing to *read* the passwords in
/etc/shadow could be made a member of the shadow-
group, and then run with SGID -- instead of running
it with full root-privlige *just* to *read*
passwords.
Or making a user game whom all games are run as, and
then making game a member of the groups owning the
soundcard, console (i.e. screencard) and any other
resource it *really needs* to use -- rather than
letting it run with root-privliges.
But still there are some users and groups who's
purpose alludes me, and I'll also like to know
when and how to use them correctly (when to
make file SUID and/or GUID, when to run a process
as a system-user, when to create a new user and/or
group, and when and to which groups a new system-
user should be made member of).
If there isn't any documentation on the subject,
I'd like to know what experiences you've made, and
would appriciate a summed-up who's-who among Linux'
users and groups list.
TIA.
-Koppe