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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

#71
post #22

Earlier quoted context omitted.

Normies are who you need to convince if you want to effect social change. If the FSF sticks to their current mission of preaching to the choir, they'll remain about as relevant as they are today, which isn't a lot.

People in power and people with money are who you need to convince..

but those in power, at least in the west, is somewhat subservient to the population as a whole (via voting - wallet or ballot).

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

#72
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…

Strategies change over time, including Microsoft's. TPM was previously envisioned as a broader physical storage for secrets, such as virtual smart cards. Microsoft no longer likes virtual smart cards, but TPM is still used for storing data for measured boot attestation. Also, at the time Microsoft was attempting to broaden support for TPM where it is restricted, such as China, which does not allow foreign TPM chips.

https://learn.microsoft.com/en-us/windows/security/hardware-...

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

#73

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.

A virtual GPU is useless if it's not provisioned with the relevant key material.

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

#74

Earlier quoted context omitted.

Yes, you can get around it by playing the video in a virtual machine and capturing it from the host. For widevine videos playing in browser it is also as trivial as disabling hardware acceleration from the browser's settings.

But doesn't this limit you to 1080p?

Correct

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

#75

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'd think so, but I've already run into a situation where DRM broke our screen capture for a live talk recording and I simply set up a camera to record the screen.

With a little bit of work (display a few calibration targets and build a quick and dirty LUT to match your display) you can get really convincing results.

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

#76
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.

The OS requires minimum hardware. To force users to upgrade their OS, discontinue the old OS, and make a new OS version, which has greater minimum hardware requirements. Now the user is buying your software again.

They're also buying new hardware which benefits the PC maker. It's a mutually beneficial relationship that forces the user to both buy the software again, and buy new hardware. (You do pay for Windows when you buy a PC, it's a cost the manufacturer absorbs. You can often receive a discount when you order a new PC by not including Windows with it.)

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

#77

Earlier quoted context omitted.

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.

Modern dedicated cameras have far more dynamic range than any HDR TV in practice. The movies have to be recorded somehow :)

> The movies have to be recorded somehow :)

I'd imagine they do this via huge (non-consumer level) cameras as well as by professional editors and graders who spend countless hours on the process.

But that doesn't really contradict your point. I don't know. I've never seen a good screen recording but I don't download pirated films so perhaps I've never seen an instance of someone really trying to get it right.

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

#79
post #20

Earlier quoted context omitted.

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.

It doesn't matter at all how out of reach it is for most people. As long as one kid in Russia can do it, the torrent is available for everyone in the world just as soon. This has already been shown with videogame DRM like Denuvo. It's so hard to crack that only a handful of people know how, and yet they end up racing eachother so eagerly every time a new game comes out that it's usually done in under 24 hours. Unless…

Denuvo has pulled back into the lead lately, it's taking a very long time for cracks to appear, if they ever do. For example Dragons Dogma 2 came out in March and still hasn't been cracked. Avatar: Frontiers of Pandora hasn't been cracked for a full year.

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

#80

Earlier quoted context omitted.

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 does sell operating systems (and user data from those operating systems). Those operating systems are typically bundled / installed by default on computers. It's in their best interests to have everyone using the "latest and greatest" for those features that weren't present (at least to the same extent) in prior versions.

This is rather contradictory. There's way less friction to selling Windows 11 licenses to existing hardware owners. Requiring a new PC only means fewer people will be running 11.
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