Subject: Suggestion for an objectoriented ffs extension
To: None <current-users@NetBSD.ORG>
From: Carsten Hammer <chammer@phyd2hammer.uni-bielefeld.de>
List: current-users
Date: 09/15/1995 11:27:29
Hi,
imagine the following:

an additional flag for directories that make this directory 
"special files only". This means only files with certain 
characteristics are allowed to be copied into this directory.
There should be a additional entry in the directory inode that
links to a executable that tests files that are copied in this
directory to be conform. The executable could be in the directory and
have the same name as the directory to be compatible with the old
filesystem. If the test is not successful there should be a special 
errornumber set for this case. As an way to use this without demand
to write "testing executables" the directory name could be eg. ppm (and
no executable "ppm" is in ppm) then all files that have a result 
containing "ppm" in a "file blablablubb" call (using /etc/magic) would
be allowed to be copied in this directory. For changing the content of
a file there should be a mechanism that tests the new file before writing
it back overloading the open() calls.
This of course slows all file accesses down but should give new ways to
protect filesystems to abuse and damage, not?

Please dont be to crude with me, its just a silly idea..:)
ciao
Carsten