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RE: [RFC] Globally creating a user and a group "root"
- From: "Morrison, John" <John dot Morrison at uk dot experian dot com>
- To: "'cygwin-apps at cygwin dot com'" <cygwin-apps at cygwin dot com>
- Date: Wed, 12 Nov 2003 10:25:21 -0000
- Subject: RE: [RFC] Globally creating a user and a group "root"
Corinna Vinschen wrote:
> On Tue, Nov 11, 2003 at 01:22:50PM -0500, Pierre A. Humblet wrote:
>> At 05:58 PM 11/11/2003 +0100, you wrote:
>>> What about generating a root group with mkgroup -l by default?
>>> The question is then, should it *also* generate an administrators
>>> or should it generate the "root" entry *instead* of the
>>> administrators entry?
>> Obviously I am for maintaining compatibility with existing
>> installations (544 must work), some of which still have Everybody
>> with gid 0 (using 0 as mapping to S-1-5-32-544 is risky).
> I think we should do the affected users a favor and remove the
> Everyone entry from /etc/passwd and /etc/group when we find one.
> This should be done by a script in the base-files or base-passwd
> package as a regular job.
Part of /etc/profile? or put it in /etc/profile.d/?
(either way I'm pro these :)
The only issue I think might cropup is permissions... another
would be that /etc/profile doesn't get overwritten.
>> Note that if a file has group S-1-5-32-544 and this is also the
>> primary group of a user, then stat() will report the file gid as the
>> gid of the user in the /etc/passwd file (due to caching). This could
>> be 544 (e.g. when running as SYSTEM with existing password files) or
>> 0 (with the new root user, with gid 0), independently of /etc/group.
> But that doesn't hurt. Either case, it's the same group.
>> This indeterminacy might cause headaches during the transition
>> period, it's hard to foresee all ramifications.
> I'm running my system for at least a year with two group entries,
> root:S-1-5-32-544:0: and admin:S-1-5-32-544:544: and I never saw any
> negative influence. It's the same group from the Windows point of
> view so no problems from that side. It's basically just another name
> and gid for the same user.
>> This being said, exim shouldn't care as long as 544 maps to
>> S-1-5-32-544. It autodetects if it is privileged and, if so,
>> setgid(544) & setuid(18) to normalize its environment (that was done
>> with Windows 2003 in mind).
> I don't understand. You were the one who figured out the 2003 problem
> with the SYSTEM account. So, erm...
>> However the current exim-config script will produce warnings if 544
>> appears after 0 (I will modify it to learn the Admins gid).
> Yeah, that will be necessary for a couple of packages. cron is a
> good candidate for problems ;-P
>> In summary, no problem (AFAICS) if 544 appears before 0. I need a
>> decent transition period before you reverse the order (affects only
>> new exim installs), and a long one before you get rid of 544
>> (affects existing installations).
> IMHO we should not wait too long. At one point we must do it anyway
> and it's easy to make the transition for the user: just upgrade Cygwin
> and the affected packages. It's no step which actually destroys
> anything but it will help all 2003 users and also users of other
> systems since the new "root" account would circumvent any permission
> problems. If a new Windows requires new privileges to do the really
> interesting stuff, just add them to "root" and you're done. Knock on
> Anyway, I think we should add "root/0" to /etc/group so that it comes
> before the "administrators/544" entry right from the beginning. What
> happens in an exim installation then?
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