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The GPU, not the TPM, is the root of hardware DRM

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Re: The GPU, not the TPM, is the root of hardware DRM

#51

Post by solarkraft »

_yb2s wrote: post #7
stackghost wrote: post #2

>The FSF's focus on TPMs here is not only technically wrong, it's indicative of a failure to understand what's actually happening in the industry. This sounds 100% on-brand for the FSF. The FSF's primary public-facing persona has peculiar computing habits so far removed from the mainstream that it's likely he has absolutely no clue how the real world works. In fact by his own statement he has to rely on volunteers to…

“Normies” are never going to care about the stuff the FSF is interested in. I don’t think you can extract the philosophy from the eccentric personalities that created it, they’re one in the same.

If you believe that normies deserve computing freedom (this doesn’t seem to entirely be consensus in the scene), it ought to be a goal to explain the benefits of it in a way that they will understand. Some may still not care, but my experience is that a good part actually does. If nothing else this is good leverage to influence change for one‘s own interest.

Re: The GPU, not the TPM, is the root of hardware DRM

#52

Post by ChuckMcM »

This is a much more accurate statement than the hate on the TPM. As the article describes, it is the GPU that has its own separate memory space that it can show on the screen without the CPU being involved at all.

I expect next generation workarounds will involve virtual GPUs.

Re: The GPU, not the TPM, is the root of hardware DRM

#53

Post by Bancakes »

tasn wrote: post #20
jakogut wrote: post #12

Earlier quoted context omitted.

There's always an analog loophole. Even if the OS is unable to access the memory storing the decrypted data, you could always just plug the output of the machine into a capture card and capture the decrypted stream that way. I suppose some monitors and TVs have "features" to cryptographically handshake with the GPU and ensure a secure link, but at some point the data must be decrypted and decoded to be displayed. Thi…

The end goal is DRM all the way to the screen. No capture cards will be allowed. It's a cat and mouse game, but I wouldn't discount these efforts as a mere speed bump. Screen enforced DRM will make things much harder. A motivated individual with the right tools and hardware hacking know how may be able to jailbreak a screen to record stuff, but that's going to make things out of reach for most people.

Or I just split the raw pixel values from the monitors t-con board.

Re: The GPU, not the TPM, is the root of hardware DRM

#54

Post by lksaar »

loeg wrote: post #47
jakogut wrote: post #12

Earlier quoted context omitted.

There's always an analog loophole. Even if the OS is unable to access the memory storing the decrypted data, you could always just plug the output of the machine into a capture card and capture the decrypted stream that way. I suppose some monitors and TVs have "features" to cryptographically handshake with the GPU and ensure a secure link, but at some point the data must be decrypted and decoded to be displayed. Thi…

Yeah, but pirate groups are getting the original streaming service's compression without re-encoding (so-called "WEB-DL"), even of 4k content. There's a weaker link somewhere.

WV L1 Keys/ PR SL 3000 keys require breaking into the TEE to steal those decryption keys.

Ever wondered why netflix 4k web-dls take a while for less popular shows?

Netfliy monitors these more tightly apparently and blacklist keys that are used to download. Then the group needs to buy some new device, the old one is burned.

Re: The GPU, not the TPM, is the root of hardware DRM

#55

Post by jsheard »

throwaway654322 wrote: post #37
MadnessASAP wrote: post #4

I have to wonder A) What does DRM realistically accomplish for the media companies? And, B) How are these DRM schemes actually being defeated? I do occasionally don my pirate hat* and have never had an issue finding what I want at the quality I want within an hour of a episode/movie being released to streaming. That would seem to indicate that these efforts at DRM are actually failing to have any noticeable effect at…

> B) How are these DRM schemes actually being defeated? 1. Disable video hardware acceleration in browser (preferably FF) 2. Open OBS studio 3. Record screen while streaming service of your choice is running. Still works in modern OSs like Windows 10. You're technically not circumventing the DRM decryption routines when you do this since the pixels displayed on screen have already been decrypted (just like recording…

That only works with the weaker tiers of DRM which are typically only allowed to stream low resolutions. As mentioned in the OP article, the stronger DRM tiers never make the cleartext visible to software and those are mandatory for high quality streaming.

Not to say the stronger tiers never get broken but it's a lot more involved than just recording them with OBS.

Re: The GPU, not the TPM, is the root of hardware DRM

#56

Post by Retr0id »

Wowfunhappy wrote: post #36
geerlingguy wrote: post #29

Earlier quoted context omitted.

With how good modern screens are, and how good cameras are (and how easy both are to hack), you could always play back the video and capture the photons through the air. There was something called Macrovision back in the VHS/DVD days that tried to defeat digital/analog conversion, and I'm sure visual techniques could be devised... But I imagine someone with a good OLED and a good mirrorless camera (or even a cell pho…

Especially when you add HDR to the mix, I think it's still extremely difficult to get a high quality screen recording, if only because it's so hard to get the exposure right.

You could record multiple exposures and merge them after the fact

(and I agree the result would likely be subpar, but better than it's ever been at any previous point in time)

Re: The GPU, not the TPM, is the root of hardware DRM

#57

Post by transpute »

elthjan wrote: post #31
mjg59 wrote: post #17

Earlier quoted context omitted.

The details don't seem clear, and I don't know that there's necessarily a unique key rather than stuff being batched, but basically yeah there's a cert chain back to a "trusted" source

how does the decryption key get into the GPU? are GPU's currently shipping preprogrammed with keys used in DRM?

Some GPUs have their own silicon root of trust.

Intel ME has a role in PAVP (Protected Audio/Video Path).

Re: The GPU, not the TPM, is the root of hardware DRM

#58

Post by AnthonyMouse »

fluidcruft wrote: post #27
bambax wrote: post #16

Earlier quoted context omitted.

Yes, DRM are a perfect example of the "Smart Cow" problem [0]. This is so obvious that, as you say (A) it's quite obscure why media companies still bother with DRM? The only beneficiaries of DRM seem to be hardware vendors, and even for them it's unclear if it's a net benefit, since it makes everything more expensive. [0] https://en.wikipedia.org/wiki/Smart_cow_problem

Probably advantage of DRM is that circumvention can be criminalized and absence of DRM implies circumvention.

What advantage does this have over just criminalizing the underlying infringement regardless of DRM?

Also, how does criminalizing it actually help anything, since the difficulty is in the scale of it happening and the difficulty of detecting it rather than the severity of the penalties, and imposing draconian penalties on random kids only turns the public against you?

Re: The GPU, not the TPM, is the root of hardware DRM

#59

Post by timewizard »

soerxpso wrote: post #38
osy wrote: post #26

> I'm going to be honest here and say that I don't know what Microsoft's actual motivation for requiring a TPM in Windows 11 is. It is quite obvious: to force people to buy a new PC. TPM provides no added security value for the vast majority of users[1] but it is a convenient hardware that has only started to become standard (fTPM) in PCs built in the last ~8 years so it provides an excuse for Microsoft to declare co…

Microsoft doesn't sell hardware. Why would they be incentivized to make you buy new hardware? Unless you're alleging that their hardware partners pushed for it, in which case there would likely be logs of communications that are pretty illegal.

Microsoft makes Xbox and the Surface. They are one of the largest consumer hardware manufacturers in the space.

Anyways Microsoft was clearly very irritated when everyone wanted to stick with Windows 7, perceiving that Windows 8 was worse in every way, and that Windows 10 wasn't a significant enough upgrade to justify the effort especially considering all the added telemetry they added to the product.

It's very reasonable, given this, that they would seek to force the upgrade cycle to occur where it clearly otherwise might not.

Re: The GPU, not the TPM, is the root of hardware DRM

#60

Post by stackghost »

talldayo wrote: post #24
stackghost wrote: post #2

>The FSF's focus on TPMs here is not only technically wrong, it's indicative of a failure to understand what's actually happening in the industry. This sounds 100% on-brand for the FSF. The FSF's primary public-facing persona has peculiar computing habits so far removed from the mainstream that it's likely he has absolutely no clue how the real world works. In fact by his own statement he has to rely on volunteers to…

I think that's a misunderstanding of what the FSF stands for overall, though. The FSF can never be a diplomatic negotiator for the benefit of free software; they are idealists, even when it serves against their own interests. Their whole shtick is not settling for half-baked appeasements, and so they're destined to be a pariah of the tech industry at-large. Neither you nor me can stop them, it's entirely within their…

There's no misunderstanding on my part; it's why I said that their ignorance is totally on-brand.

>more like the mainstream has abandoned free software.

Indeed, because free software development is largely driven by ideological purity rather than feature parity. Mainstream users see Free Software people as irrelevant kooks, and thus easy to dismiss, which is why Free Software has so utterly failed as a movement.

>You know, the FSF would probably argue that our computing habits are the peculiar one.

I'm sure flat-earthers feel that my belief that earth is an oblate spheroid is peculiar, too. Of what relevance is that to anyone?

>And unless you can tell me about the code your iPhone runs in detail, they're probably (albeit begrudgingly) correct.

We'll have to agree to disagree. The emacs developers don't even understand how large chunks of emacs work (per emacs-devel), for example. There's too much software out there for one person to keep in their head. This is not a reasonable heuristic.

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