[BLUG] Unix conventions for controlling file access

[Dave Monnier REN-ISAC]

-----BEGIN PGP SIGNED MESSAGE-----
Hash: SHA1

Mark Krenz wrote:
>   I'm curious to get opinions on this.  I'm working with some support
> technicians for a software company that shall remain nameless for now.
> 
>   Anyways, a problem came up where temporary files are being written to
> /tmp by a program and then showing up in the output of lsof as
> (deleted).  When talking with the support people about this, they said
> that their method of controlling access to these files is to create
> them, then unlink the file while the program is still running.  This
> makes the entry disappear from the directory listing.  The program
> should still be able to access the file when the filehandle is open, but
> for the most part other programs cannot access it.
> 
>   What do you think about this?
> 

Sounds like tomfoolery to me. I'd say this qualifies as another act of
security theater.  I wonder why they would go for this card trick over using
actual access control methods.

This also sounds like a great way to have their file corrupted.

- -Dave
- --

|              Dave Monnier - dmonnier_at_ren-isac.net              |
|             http://nicholas.ren-isac.net/dmonnier/             |
| Principal Security Engineer, REN-ISAC http://www.ren-isac.net/ |
|     24x7 Watch Desk: +1(317)278-6630, ren-isac_at_ren-isac.net    |

-----BEGIN PGP SIGNATURE-----
Version: GnuPG v1.4.6 (GNU/Linux)

iD8DBQFGl5pMBIf6jlONJjIRAlwsAJ4zBR9PvUCt1plMLZ8Bsn/f2C+O6gCeLXIA
U+0VBgeKa20Iyztn6i3E/hI=
=UxI6
-----END PGP SIGNATURE-----