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Date: Wed, 27 Nov 1996 17:24:19 -0600
From: peter@taronga.com (Peter da Silva)
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To: hackers@freebsd.org
Subject: Re: looking for an idea
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In-Reply-To: <199611260923.AA137920219@ws2301.gud.siemens.co.at>
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In article <199611260923.AA137920219@ws2301.gud.siemens.co.at>,
Hr.Ladavac <lada@ws2301.gud.siemens.co.at> wrote:
>> How about having the client create a file of mode 000, and then pass that
>> open file descriptor back to the server?  Since it's mode 000, only the 
>> owner of the file could have opened it (or chowned it to 000).  The file can
>> either be created randomly by the client, or specified by the server.

>Won't work on SysV.  Anyone can chown(2) his own files to anyone else.
>The funny thing about it is that they claim they support quotas :)

It will if you insist the file is chmod +s. The only person who can create
a setuid file owned by user "A" is user "A".