Re: Re: Trusted OS...

["Marcus J. Ranum" <mjr () nfr net>]

Paul McNabb wrote:

> Yes, I classify Sidewinder on BSDI as a trusted OS (in addition to the
> LOCK stuff), because it implements a mandatory access control policy
> which is universally applied and it provides the ability to control
> privilege operations, both of which are defining characteristics of a
> trusted OS (along with the design/implementation process that is intended
> to meet evaluation criteria).  The fact that domain type enforcement is
> not a Bell-LaPadula model doesn't eliminate it from the running.

No, I wasn't eliminating DTE because it's not Bell-LaPadula. I was
questioning whether or not it's really a trusted O/S because what
they did was take a commercial O/S and jam some trusted features
into it. You know as well as I do that doing so does not automatically
make the whole O/S trustworthy. I never managed to pin them down
as to what degree of other review of the O/S they performed. Various
sources told me "little to none."  When you're building a trusted
operating system, you go over the whole thing - it's a more involved
process than (ahem!) just slapping a few function calls in front of the
jump table on file system and socket system calls.

One of the reasons LOCK was such a humongous project was
because Secure _did_ try to build a trusted operating system. When
they built sidewinder they looked at what it would take to make a
firewall run on a _real_ trusted O/S and decided that they'd just
slap a few features from LOCK into BSDI. I was at TIS at the
time and also looked at putting a firewall on Trusted Xenix. ;)
So the same logic went through my head. Those darned trusted
O/S are so klunky to work within it's a nightmare. Simply lifting
a few nice features from them into a decent O/S is about the
only way to go.

That being said, BSDI is a better O/S than most of the trusted
operating systems, anyhow. ;)

> What is "orange book fairy dust"?

Orange Book Fairy dust is what you sprinkle on top of
an ordinary commercial O/S like BSDI in order to make
your customers think they're getting a real trusted
operating system that was designed from the ground
up to be secure. It's synonymous with marketing
hype. ;)

mjr.