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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

#391

Post by mjg59 »

forty wrote: post #387
lxgr wrote: post #378

Earlier quoted context omitted.

But so does a USB-connected security dongle. Does that make USB "complicit in enforcing DRM"? TPMs are really just embedded Yubikeys. Unless your UEFI/BIOS "conspire" to supply them with boot measurements, and your OS in turn conspires with that to carry these measurements forward and provide them at the application layer, TPMs can't harm your freedom. TPMs are a much more "freedom neutral" technology than people gen…

The TPMs are already provided with boot and OS measurements for secure boot purpose which would allow DRM to confirm you use an approved OS kernel, so I guess the computer is already conspiring. And the conspiracy could be enforced by videos distributors in exchange for the privilege of having HD content.

It could, but why? They've come up with a solution that avoids having to place any trust in the OS at all, so why introduce additional complexity and fragility?

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

#392

Post by no_time »

mike_hearn wrote: post #383
no_time wrote: post #377

Earlier quoted context omitted.

>Some remote servers won't give you service if you do that This is exactly my problem. Before ideas like this surfaced, the demarcation line between who controls what was purely based on ownership. The machine that I own acts only on my behalf and in my best interests, the server that you own does so for you (or atleast for PCs this has always been the case) TPMs, attested bootchains and whatnot trample on this whole…

It's not just you but what people who hate remote attestation tend to forget is that it's a sword that cuts in both directions. Servers can remotely attest to you, not just the other way around. Signal is an example of an app that demands a remote attestation from the server before uploading your sensitive data. Attestation is just a tool. It can be used for all kinds of things and doesn't privilege one side or anoth…

Fair points. I was aware of this anti fraud angle of WEI/attestations before.

From this point on this is more of an emotional argument rather than a technical one, but I feel like the negative effects way outweigh the positive ones. Giving MORE power (be it technical or poltical) to big tech companies is just tipping the scales in their favor so much we will even worse off than we already are.

But if you work in anti-fraud and are fixated on solving this problem as effectively as possible, I can imagine not caring about this too if I were you...

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

#393

Post by cryptonector »

mjg59 wrote: post #358
cryptonector wrote: post #231

Earlier quoted context omitted.

> How would the GPU verify it's speaking to a real TPM? Option 1: as I said, the GPU could have its own, and yes in that case the EK cert would be known to the GPU (or it could have a platform-like cert issued by the GPU OEM). Option 2: the platform vendor can teach the GPU the EK cert (or the public key for some primary key anyways). Option 3: the GPU could learn it on first use. > charitably let's say that's a sign…

> What do you mean "too new"? Like, you replaced your TPM? That's a thing on servers, but not laptops. I buy a GPU in 2025. I buy a new motherboard in 2026 and plug the GPU into it. How does the GPU learn about the new EK CA? These are devices that can be moved between systems, you can't delegate this to the platform vendor or TOFU, the GPU would need to generate independent trust in the TPM.

One way I might handle this would be to have a TPM on the GPU itself. Then you can move the GPU about all you like, and it will work. The GPU would have to implement an API and protocol that allows the DRM site to do attestation via software running on the CPU, but that seems doable.

The other way would be accept that the GPU that the content is to be played on might not be the same as the device on which the TPM exists. You could have the GPU on a computer halfway around the world and use a TPM from another system to which the user account is registered on the DRM site. Not great, but as a form of account sharing and subject to account sharing detection, it's not bad.

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

#394

Post by cryptonector »

mike_hearn wrote: post #343
cryptonector wrote: post #297

Earlier quoted context omitted.

Amazon has their Nitro secure enclave system that's pretty easy to use. IIUC its based on isolating the code that runs it and in it onto one core set aside for just that, possibly just when it's needed. Having the SE be easy to use is a key thing. Not that the Nitro approach extends well to consumer hardware (it doesn't).

The problem with Nitro is that a TEE doesn't really work if the adversary makes your CPUs. SGX works, conceptually, because of the division of labor between Intel and the people running the machines: 1. Intel can't break into your enclave even by subverting SGX, because it doesn't have access to the computers (isn't your cloud operator or network admin). 2. The people with access to the computer can't break into your…

Governments as threats... that's way beyond what people who want DRM consider within their threat models. TFA was about TPM not being relevant to DRM.

For most public cloud users having to trust the cloud operator is just a fact of life. Even if the SE were strong up to but excluding collaboration of the CPU vendor and the cloud operator, the user would have to run most if not all of their code in the SE, which is one thing the SEs invariably can't do.

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

#395

Post by paxys »

watermelon0 wrote: post #159
majormajor wrote: post #10

Earlier quoted context omitted.

DRM has likely had a big impact in shifting the casual consumer conversation to "hey they're gonna start down on account sharing" from early-2000s style "here's a straight-up copy I made for you." And this helps prop up the "they'll get a Netflix account to binge the same three shows over and over" part of the business model. The cumulative monthly cost adds up but it feels cheaper than forking over a few hundred buc…

In many cases, downloading torrents and watching on a laptop/PC has a better UX than using streaming services. For example, it's impossible to watch 4k content on popular streaming services if you use Linux, and even with macOS/Windows you need a specific combination of hardware + OS + browser, if a service even offers it.

Without giving them any further instructions, ask all your non-technical friends and family members to (1) watch a popular movie on Netflix/iTunes/Amazon/Google Play and (2) torrent the same movie. Report back on how many are able to successfully do 1 vs 2. That'll tell you how good the respective user experiences are.

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

#396

Post by michaelt »

p_ing wrote: post #252
michaelt wrote: post #247

Earlier quoted context omitted.

The TPM is a great thing, from Microsoft's perspective. Because Microsoft have the Secure Boot code signing keys. And none of their users expect a "free software philosophy" that lets them use their own modified kernel, or DKMS to build new copies of kernel modules on demand - so you don't have to make users jump through any "machine owner key" hoops. And a lot of your customers are big corporations who barely trust…

> TPM is superior to things like Yubikeys, precisely because of its inflexibility TPM also offers PIN or Password options. It is flexible.

Yubikeys offer PINs and passwords, a physical user presence button, finger print sensors, NFC, and you can use one key on different PCs, you can deal with PC hardware failures by moving the key and deal with key failures with a backup key, and and it's compatible with Windows, Linux, OS X, Android and iPhone.

So they're a heck of a lot more flexible.

But in a corporate environment, you might not give a shit about Linux support, and you might think it's better if the user can't unplug the key and plug it into another PC, because corporate workers should only connect to corporate systems with their corporate-issued laptops, and corporate helpdesk will sort out any hardware problems.

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

#397

Post by DoctorOetker »

anal_reactor wrote: post #163

Ah yes. DRM. 1. Companies offer service that people don't want to pay for, and blame piracy. 2. Someone realizes that they can eliminate piracy and make lots of money by offering good service. 3. Piracy slowly dies, because people prefer €5 monthly subscription over torrent. 4. Other companies catch up. The market gets fragmented. By the nature of the market, it becomes impossible for one company to offer clearly goo…

7. People blame FSF for not ridding them of evil as they walk through the valley of death.

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

#398

Post by michaelt »

dingnuts wrote: post #251
michaelt wrote: post #247

Earlier quoted context omitted.

The TPM is a great thing, from Microsoft's perspective. Because Microsoft have the Secure Boot code signing keys. And none of their users expect a "free software philosophy" that lets them use their own modified kernel, or DKMS to build new copies of kernel modules on demand - so you don't have to make users jump through any "machine owner key" hoops. And a lot of your customers are big corporations who barely trust…

> while most Linux users are quite happy remembering long unique disk encryption passwords thanks very much. Which brings something up: how do you get back in if you suffer a traumatic brain injury or something like that? I feel like a lot of software assumes the operator can do things like remember unique passwords for a long time. Sure, I can do that NOW, but will I still be able to in my seventies?

Well, you could write down your password and give it to a trusted friend, a lawyer, or whatever so people can get into your documents if the worst should ever happen.

Personally I choose not to do that. My girlfriend sent those nude photos to me, not to my heirs or the executor of my estate. It's impossible to "get back in" without the password, and that's how it's meant to be. Of course if you've got no sexy photos, and lots of treasured photos of your family growing up, you might feel differently!

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

#399

Post by DoctorOetker »

no_time wrote: post #143

The author is correct in that media DRM is tied to GPU vendors on the field right now. But hardware backed DRM can be so much more invasive beyond that. I have no doubts the long term goal of MS is to have a Windows version of Play Integrity.[0] So total control over everything that happens on your device. Just to give an example of what could happen if this becomes reality: https://en.m.wikipedia.org/wiki/Web_Enviro…

Consider a benevolent cryptographer, who is able to break modern asymmetric cryptography, but refuses to use it for petty personal gain, and is fully aware of the dangers of publishing it (why this cryptographer put it in dead man's switches instead, with recipients randomized over nearly all power blocs, political groups, companies, ...)

The cryptographer never implemented it on daily compute devices.

Perhaps this cryptographer would be willing to risk a low communication round release of private keys corresponding to public keys in ROM or burnt in eFuses etc... but only if the public key dump is sufficiently large and encompassing.

From the perspective of the cryptographer we are all whining wankers, and we should just collect all the public keys as a wishlist.

The cryptographer care naught about "liberating" hour long advertisements for the militaries or intelligence agencies etc. The cryptographer does wish sovereign compute to fellow humans, a primordial requisite for effective democracy.

====

While I understand the average programmer would ascribe an incredibly low probability to the above, the absolute absence of such a comprehensive public key dump is not in proportion to the probability considered.

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

#400

Post by forty »

mjg59 wrote: post #391
forty wrote: post #387

Earlier quoted context omitted.

The TPMs are already provided with boot and OS measurements for secure boot purpose which would allow DRM to confirm you use an approved OS kernel, so I guess the computer is already conspiring. And the conspiracy could be enforced by videos distributors in exchange for the privilege of having HD content.

It could , but why? They've come up with a solution that avoids having to place any trust in the OS at all, so why introduce additional complexity and fragility?

I don't know, maybe because not everyone has the right GPU with DRM, while the TPM is conveniently mandatory? :)
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