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From: xskittenz.org
Date: Sun Feb 03 2002 - 08:14:00 CST

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    on Sun, Feb 03, 2002 at 02:32:20PM +0100, Wojciech Bojdol wrote:
    > Have you got any users using dump ?

    nope! But dump works without setgid tty, and so could easily be installed
    by any one of them if they wanted it. Why waste space by making them do that?

    > > It would be nice to have a good security vs. usability balance in the
    > > default install.
    >
    > ... like in linux ? :)

    The list I have for making linux satisfactory is longer than the one for
    NetBSD, and includes the mess of trying to locate current patches and
    tarballs (eg, free s/wan)

    > > Edit /etc/newsyslog.conf and remove the aculog entry
    >
    > When we're talking about defaults - old wtmp files shouldn't be gzipped,
    > because last can't read them.
    > What users have to find in /var/log/messages ?

    wtmp files can get *huge* quickly, and compress quite well. Also probably
    only get viewed rarely once they are archived. Better to save space
    than save a few key presses on a rare occasion.

    > > chgrp users: /usr/bin/at /usr/bin/atq /usr/bin/atrm /usr/bin/batch
    ...
    >
    > I think, that making new groups for some of bin's is good idea.
    > For example we could make group ,,jobs'' and chgrp jobs /usr/bin/at
    > /usr/bin/atq /usr/bin/atrm /usr/bin/batch /usr/bin/crontab,
    > so that only people in that group could use that.
    > That files could have setuid bits, but then when there's a bug only people
    > from that group could use it.

    The idea behind chgrp'ing to users is that daemons (eg, httpd) and so on
    are not a member of the users group, and so shouldn't be able to
    set a password on their account, play with at/crontab, etc.

    This is a very site specific setting. Eg: it breaks on a system
    where passwd is used via a web interface or where pppd runs at.
    This is a kludge I use on a gateway to get around a 2 hourly ISP disconnect
    that gives me no notification. (It just stops routing packets)

    > We should also make named not running as root by default.

    and chrooted, agreed. I think it does in -current. An MTA is pretty
    much required by the default crontab, which is why I include switching
    to postfix.
    It should (I think) also be possible to chroot apache, and allows perl/php
    to work (using nullfs/umapfs)

    > > Run find / \( -perm -04000 -o -perm -02000 \) -exec ls -ld {} \; to see
    > > If I missed anything.
    > > Run find / -perm -00002 -exec ls -ld {} \; and remove as many
    > > world writable directories as is acceptable.
    >
    > What about using ~/tmp ?
    > It's more secure.

    Not everything will listen to $TMPDIR.
    Symlinking ~user/tmp to /tmp/users/user, where /tmp/users is recreated
    each boot might be worth doing in some case. (I do something similar with mfs)

    > > mount /, /var and /tmp (if it's on a seperate filesystem to /)
    > > with options nosuid and nocoredump
    >
    > and /home with noexec ? :)

    IMHO, that's a tiny bit too far. I like filling ~/bin and developing
    software under ~. /home could be nosuid and /tmp could be noexec.
    I think a noexec /tmp might break something though.