[213] in The Cryptographic File System users list
Re: "out of band" cdetach?
daemon@ATHENA.MIT.EDU (Valdis.Kletnieks@vt.edu)
Tue Oct 17 14:31:58 2000
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To: Steve Bellovin <smb@research.att.com>
Cc: cfs-users@research.att.com
Subject: Re: "out of band" cdetach?
In-Reply-To: Your message of "Tue, 17 Oct 2000 13:39:25 EDT."
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From: Valdis.Kletnieks@vt.edu
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On Tue, 17 Oct 2000 13:39:25 EDT, Steve Bellovin <smb@research.att.com> said:
> Is there any way for a daemon process to cdetach all currently-attached
> directories? I'd like to do something like that in an apm suspend
> script.
Well, the source for cdetach.c is really simple. The two problems I see are:
1) You have to play UID games if there's multiple UID's with outstanding
cattach's. Since the cdetach.c code just does 'ap.uid = getuid();', it
doesn't look TOO hard to just iterate and fake them up as needed.
(Note for CFS V2 - this is a DOS attack waiting to happen ;)
2) You'd have to do a readdir() of /crypt (or whatever mount point you use)
to get the names of the directories to mass-detach. This would however
Lose Big Time if you use the 'leading-dot name mangling' feature. Also,
I'm not sure what scheme you'd use to get the name of the mount point
into the program.
--
Valdis Kletnieks
Operating Systems Analyst
Virginia Tech
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