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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

#11

Post by lotharcable »

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…

> A) What does DRM realistically accomplish for the media companies?

Control publishing rights, platforms, software and hardware that is used for the consumption of said media.

The publishers control the DRM, which then needs to be licensed by television makers, software writers, and such things. Then that gives them control over how is it presented, how it is sold, how it is consumed and it forces everybody to agree to their terms.

It is a power thing. They want to have power over other businesses. DRM laws help them do that.

> How are these DRM schemes actually being defeated?

Well I don't follow DRM piracy stuff, but at a high level the people that want to consume the media must be able to decrypt it to enjoy it. So if you buy one of these DRM devices and figure out how they work then you can decrypt anything that is compatible with them.

And you only need to decrypt it once since digital media can be copied a infinite amount of times.

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

#12

Post by jakogut »

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…

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. This doesn't seem like much more than a speed bump for a motivated individual.

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

#13

Post by userbinator »

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…

[flagged]

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

#14

Post by _yb2s »

There’s some technical details missing here. I get decrypting the video on a gpu makes it harder to screen capture, but can’t you just still emulate the GPU in software or directly capture the digital video output? The GPU still has no unique hardware private key, right?

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

#15

Post by zb3 »

> GPU vendors have quietly deployed all of this technology

Citation or technical details needed.

Obviously it "makes sense" that for 4K HD content you "probably" want to offload the decoding into the GPU, but this is the first time I see this mentioned and there are no links to technical details.

In contrast, TEE / TrustZone and even the recent AVF with pVM - these are well documented technologies.

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

#16

Post by bambax »

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…

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

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

#17

Post by mjg59 »

_yb2s wrote: post #14

There’s some technical details missing here. I get decrypting the video on a gpu makes it harder to screen capture, but can’t you just still emulate the GPU in software or directly capture the digital video output? The GPU still has no unique hardware private key, right?

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

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

#18

Post by jsheard »

_yb2s wrote: post #14

There’s some technical details missing here. I get decrypting the video on a gpu makes it harder to screen capture, but can’t you just still emulate the GPU in software or directly capture the digital video output? The GPU still has no unique hardware private key, right?

Capturing the digital video output is supposed to be prevented by HDCP encrypting the signal, but in practice that's pretty well broken. That is a (slowly) moving target though, each time they roll out a new HDMI version (e.g. for 4K) they get to enforce a new version of HDCP which needs to be broken all over again.

I don't think the version of HDCP attached to HDMI 2.1 has been broken yet but that's kind of a moot point because no current video formats require more than HDMI 2.0.

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

#19

Post by zb3 »

zb3 wrote: post #15

> GPU vendors have quietly deployed all of this technology Citation or technical details needed. Obviously it "makes sense" that for 4K HD content you "probably" want to offload the decoding into the GPU, but this is the first time I see this mentioned and there are no links to technical details. In contrast, TEE / TrustZone and even the recent AVF with pVM - these are well documented technologies.

Integrated GPUs exist. Wouldn't it make more sense that the "high value" content should not be exposed to any external GPU? Then we can treat those integrated ones as part of the "TEE". That's my speculation, waiting for details.

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

#20

Post by tasn »

jakogut wrote: post #12
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…

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.

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