Date: Wed, 9 Apr 2008 18:12:04 +0200
From: Corinna Vinschen <corinna-cygwin AT cygwin DOT com>
To: cygwin AT cygwin DOT com
Subject: Re: [ANNOUNCEMENT] Updated: csih-0.1.3-1
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On Apr  9 10:55, Charles Wilson wrote:
> On Wed, 9 Apr 2008 14:09:56 +0200, Corinna Vinschen wrote:
> >Looks ok, but I have a few questions/comments.
> >
> >- When the script starts, the following text appears:
> [snip verbose output]
> >However, I think the whole message is too noisy and confusing for
> >non-admins.  
> 
> That is odd. That particular text was mostly taken from ssh-host-config,
> and should only appear if your script calls
> csih_select_privileged_username() with no arguments (or if you are using
> csih-0.1.3, instead of CVS csih) -- that is, the way ssh-host-config
> calls it.  The older version of csih_select_privileged_username ignores
> its arguments; the newer one honors the '-q' option that [my]
> ssh-user-config gives it. In which case, what you should see is
> something like the following (but only if nt2003 or
> csih_FORCE_PRIVILEGED_USER):
> 
> *** Info: The following privileged accounts were found: ....
> *** Info: This script will assume that ${opt_servicename} will run under
> the"
> *** Info: '${username}' account."
> *** Query: Will ${opt_servicename} run under a different account?" 
> [yes/no], if yes, then:
> *** Query: Enter the user name used by ${opt_servicename}:
> 
> Hopefully, that's more acceptable for ssh-user-config?

My bad, I didn't update csih to CVS.  I still think that's too much for
ssh-user-config.  But since we don't need the setfacl anymore, that's
a moot point now.

> >Additionally, given that Cygwin opens
> >files always with BACKUP_INTENT for a while anyway, and given that the
> >service account is a member of the administrators group, which has
> >backup user rights, there's not much reason anymore to add the service
> >account to the ACL.  I fear that's just old cruft in the ssh-user-script.
> 
> Well, that's up to you. I wanted to do something that was as close to
> equivalent as the existing ssh-[host|user]-config, with only those
> changes necessary to support a common service account whose name might
> not be 'sshd_service'.

And that was really very nice.  I'm not trying to critizise the general
approach.  I just think we (that is: I) should get rid of the entire
message and the setfacl in ssh-user-config.

> >The query "Do you want to use different name?" is a bit upside down,
> >IMHO.  The query should be rather phrased positively "Do you want to use 
> >t name?"
> 
> I already addressed this:
> http://cygwin.com/ml/cygwin/2008-03/msg00447.html
> 
> Phrasing that question in the opposite sense breaks postinstall scripts,
> where auto_answer="no". That is:
> 
> Do you want to use this name? <no>
> Enter the name you want to use: <hangs>
> 
> ...and that would be bad. Now, the openssh package does not invoke its
> config scripts from /etc/postinstall, but others do. So I need to take
> care that the auto_answer="no" case never hangs.

Ok, agreed.

> >  svc_user=$(regtool get '/HKLM/SYSTEM/CurrentControlSet/Services/$1/ObjectName')
> >  svc_user="${svc_user/\.\\/$COMPUTERNAME}"
> >  svc_user=$([ "$svc_user" = "LocalSystem" ] && echo "SYSTEM" || echo $(fgrep "${svc_user}" /etc/passwd | cut -d: -f 1))
> 
> (a) csih_select_privileged_username (in CVS) already optionally accepts
> the service name in addition to the -q option. Currently it is only used
> to customize the Info: messages (see ${opt_servicename}, above).  So
> this is even easier to add than you imagine -- if it is truly desirable
> to do so.
> 
> (b) You could also do 'foo=$(cygrunsrv -V -L ${service} | sed -n
> '/Account/p' | awk '{print $NF}'); foo=$(basename $foo)' which amounts
> to the same thing.

Urgh!  Isn't it embarassing that *I* missed to use cygrunsrv for that?

> (c) But what if ${service} has not yet been installed, even though [a]
> common service account exists [perhaps used by some other installed
> cygwin service]?  Then you'd still need the existing logic...

Right, but that should probably be a fallback.  If the service exists,
it could run under *any* account.  It might be interesting for csih to
check always for the user running the service, not only on 2k3 and
above.

> Furthermore, remember that these routines are shared between (the more
> common) install-a-service config scripts, and (less common) user config
> scripts like ssh-user-config.  In the former [common] case, assuming
> ${service} is not installed, you will always need the existing logic.

For the ssh-user-config script you won't need it anymore.  I have a 
hard time to see that a normal user should know or decide about stuff
like that.  Nothing of that is actually helpful or informative for a
"just-a-user" user.  And except for setting permissions (which isn't
necessary!) I really think we should not call this function from pure
user config scripts.


Corinna

-- 
Corinna Vinschen                  Please, send mails regarding Cygwin to
Cygwin Project Co-Leader          cygwin AT cygwin DOT com
Red Hat

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