improved dos attribute handling

[Ola Lundqvist]

Hello again.

This is the next issue for which I have created a patch.

There is a problem with the current dos filemode option. The
problem is that you can only set read only but not remove it
again. You can of course not because you do no longer have
write permissions to the file. My fix change the behaviour to
check the directory and file for permissions.

If the user has write permission to the dir and
(is owner of file, or member of group or part of group) of
the file the read-only can be removed. The code is tested
but not for very long time. Right now just a week in a
production server. I have not checked if it is possible to
bypass something but I do not think so. I think I have catched
all cases, but checking is good.

For other information, see:
http://bugs.debian.org/178801

The patch is located at (against the debian version of 2.2.3a):

http://cvs.opal.dhs.org/viewcvs.cgi/samba-fixes/dchmod/samba-dchmod.patch?rev=1.1&content-type=text/vnd.viewcvs-markup

or just http://cvs.opal.dhs.org/viewcvs.cgi/samba-fixes/dchmod/
if you want to look at the files directly. The patch includes
the changes to the smbd makefile and dosmode.c file.

I had to write some functions myself because the normal C-functions
did not really behave as windows functions... That did not surprise
me a lot though. :)

Best regards,

// Ola

-- 
 --------------------- Ola Lundqvist ---------------------------
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