[gentoo-user] OT: Filesystem permissions

[Florian Philipp]

Hi list!

I'm a bit dissatisfied with the way umask and filesystem permissions
work and I'd like to know if a) this is due to misunderstanding on my
part and/or b) there is a clean workaround I'm unaware of.

Let's say I have a system with various users working on some sensible
data. Therefore I have to set up various security policies regarding
file permissions and so forth.

For example every $HOME-directory should be only readable to the user
himself (e.g. for user phil_fl: chown phil_fl:phil:fl; umask 0077 or
0007).

Then there might be a common folder for all users in a specific group
as a simple way of sharing files. These shall be accessible by every
user in the group but by none else, so for the user phil_fl and the
group users: chown phil_fl:users; umask 0007.

As we see, the umask itself isn't the problem (in this special case)
but the group is it, however, there might be cases in which need to
change both for special folders. How do I do this without needing any
interaction from the users?

Thanks in advance!

Florian Philipp