Re: Fw: signed kernel modules?

From: Richard B. Johnson
Date: Mon Oct 18 2004 - 06:30:10 EST


On Sun, 17 Oct 2004, Bodo Eggert wrote:

Richard B. Johnson wrote:

One can make a 'certified' kernel with 'certified' modules
for some hush-hush project. Adding this kind of junk isn't
how it's done. You just take your favorite kernel with the
modules you require, you verify that it meets your security
requirements, then you CRC the kernel and its modules. You
keep the CRCs somewhere safe, available from a read-only
source like a CD/ROM or a network file-server. You automatically
check these CRCs occasionally using a read-only program on
read-only source like the network or a CD/ROM. If the checks
fail, you call the "super" and shut down the system.

If a malicious module loads, you lose instantly. You cannot relaibly check
module integrity on this system anymore. E.g. the malicious module might
patch the module checker to check a signed module instead of the malicious
one. Or the Exploit saves the old module, puts in the patched one, loads it
and puts the old one back in place.


What malicious module? They have all been certified. That ARE NO
OTHER modules. If you don't do it this way, i.e., if you allow
anybody to load a module, then you have no security, regardless of
what's in the module, the loader, or the kernel. Any crap inside
either of these is crap. Then can all be modified to do anything
so gigibytes of "protective" software is absouye bullshit, and
a lot of memory wasted.


Cheers,
Dick Johnson
Penguin : Linux version 2.6.8 on an i686 machine (5537.79 BogoMips).
Note 96.31% of all statistics are fiction.

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