That reddit post was mine. I just created a new account there, but somehow my comment doesn't show up, no idea why. But fortunately there is HN :)

I would not call it an enterprise security solution. It is also very much aimed at the ordinary user's machine. It is important for DRM (the infamous TPM chip is now basically an app running inside the IME/PSP). Decryption of DRM content takes place inside the IME and it is presented using a protected media path. So the content industry wants to have that on your computer. Intel also tries to market it by offering security solutions like 'Intel Anti Theft Technology' or its 'True Key' App which utilizes the IME. It makes your machine uniquely identifiable and it should serve as a store for all your secrets (like biometrics, passwords etc). Intel is also opening the IME up for third parties to create software for it. So your bank might e.g. run it's software inside the (considered safe and secure) IME. But of course such software has to be signed by Intel before.

Ruan even hints in his book at the possibility that one day the IME might become just as powerful as the user system. So it would be possible to run e.g. a game completely inside the IME, absolutely safe from the malicious user who might try to copy it. All you get is the output on the screen and the speakers. So the (considered unsafe) ordinary user space would just remain for running and storing trivial tasks and information. Everything else runs hidden away from you.

And all of this is supposedly for your own good and security. I would call it a dual use technology which (dis)owns the user.

But then I don't get why they wouldn't market two different CPU's, one backdoored and user-controlling one and a normal maliciousness-free one. It's then up to the game developers to require a system of the former type to play their game. Then gamers get these and people who mind their privacy and security in computing get the latter. Win-win, right?

I mean, people will anyways get computers that obey them. Either an ARM-based or something completely different.

There are (at least) two different markets here. People who just want to enjoy products and media (which might be DRM'ed but they don't care) and people who want a computer they can trust. Why should AMD or Intel restrict themselves to the former market?

> I just created a new account there, but somehow my comment doesn't show up, no idea why.

Probably just got detected as spam by Automod and removed. If you message the mods for /r/linux they'll probably approve it for you.

> a case of a security architecture that is literally founded upon obscurity (ie, keeping the keys secret)

Huh? Relying on the secrecy of keys rather than secrecy of the code is the _exact opposite_ of security through obscurity.

I can see their point. One can view obscurity as "not common knowledge" or "information that can be found if you look hard enough."

A secret key technically falls in the later. You have it somewhere. If someone looks hard enough, they can find it. It may take ridiculous effort to the point of being impractical, but that is still obscurity.

I recognize that when people speak of "security through obscurity" they are referring to esoteric knowledge that is difficult but not impractical to find.

Ruan writes in his book in chapter 4 "The Engine: Safeguarding Itself before Safeguarding Others":

"In addition, there is a basic guideline for realizing security: Never rely on security through obscurity. When designing security hardening features for the engine, it is always assumed that all firmware source code and internal architecture documentation may be obtained by attackers. The engine’s security design principle is to harden the product by applying proven cryptography and security primitives, rather than rely on hiding secrets in the code or documents."

So they cast their secrets in silicon I guess, which would be incomparably harder to recover.