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Why Rosyna Can't Take a Movie Screenshot

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Re: Why Rosyna Can't Take a Movie Screenshot

#61

Post by ris »

jrockway wrote: post #27

This is all ultimately pointless because it's not like the video decoder checks the integrity of its own code or the CPU running it or the compiler that compiled it or that the OS it was tested against is actually running. (Reflections on trusting trust.) Nothing actually cares about secure boot or end-to-end code validation; Apple doesn't even include equipment on their mainboards to do this anymore. Meanwhile, if y…

"Intel's just using Hollywood's fear of piracy"

DRM has very little to do with piracy. Hollywood know perfectly well that DRM will not stop a determined pirate and a movie only has to be ripped once to be pirated indefinitely.

It's about control. It's about the studios always having a seat at the bargaining table when new products/devices are being floated. They fear becoming a commodity supplier.

Re: Why Rosyna Can't Take a Movie Screenshot

#62

Post by userbinator »

pgeorgi wrote: post #45
Audiophilip wrote: post #34

Earlier quoted context omitted.

@pgeorgi: >All Intel chips since 2010 or so have the management engine. Do you have sources for this? I wanted to verify it, but after a few Google searches I could not find anything that states exactly that. I have a Haswell CPU, but I have no Management Engine settings in my BIOS. How does the vPro feature correlate with the Management Engine? Because not all Intel CPU's come with vPro. Or is that only a firmware d…

My source is that I work on coreboot, where we have to interact with that stuff all the time. It's actually somewhat hidden in our haswell driver because so much is now binary-only on Intel platforms. But look at http://review.coreboot.org/gitweb?p=coreboot.git;a=blob;f=sr... whose comments refer to both "ME" (the management engine) and "PAVP", which is the "Protected A/V Path" referred to in the article. One sure wa…

From that file:

    pci_or_config32(PCI_DEV_HSW, 0xb0, 1
What is "BDSM"? It almost seems like a strangely appropriate name for another DRM feature.

It's actually somewhat hidden in our haswell driver because so much is now binary-only on Intel platforms.

One thing that I've noticed browsing around Coreboot sources is that the source code is rather opaque - full of "magic constants" with little to no meaning. It may be "open-source" and GPL, but I don't think it's in the spirit of open-source to have code that can't really be understood. I can get the same depth of information by just disassembling a BIOS and seeing what addresses it writes with what values. If anything, it feels like someone has found a way to "contribute" to open-source without actually disclosing much. (Aside: how do binary-only blobs get let into Coreboot? It sort of defeats the purpose, doesn't it?)

and see the system either not start at all, or reliably shut down after 30 minutes

That second alternative is just scary. Really scary, like a hidden silent killswitch.

Re: Why Rosyna Can't Take a Movie Screenshot

#63

Post by [deleted] »

jrockway wrote: post #27

This is all ultimately pointless because it's not like the video decoder checks the integrity of its own code or the CPU running it or the compiler that compiled it or that the OS it was tested against is actually running. (Reflections on trusting trust.) Nothing actually cares about secure boot or end-to-end code validation; Apple doesn't even include equipment on their mainboards to do this anymore. Meanwhile, if y…

[deleted]

Re: Why Rosyna Can't Take a Movie Screenshot

#64

Post by Fuxy »

Pyxl101 wrote: post #4

Are chips with this feature sold in consumer devices? I'm planning to buy a new computer soon. How can I avoid or boycott the chips in question? Or can the feature be definitively disabled through the BIOS? If I buy a computer, then I want to own it completely and not have arbitrary DRM bullshit remove capabilities. If I wish to take a screenshot of copyright content and share it with friends (fair use), then I shoul…

Intel Xeon processors don't seem to ship with this. Then again intel doesn't expect many people using a xenon on a workstation motherboard as their PC.

I got lucky getting this.

Re: Why Rosyna Can't Take a Movie Screenshot

#65

Post by mike_hearn »

ris wrote: post #61
jrockway wrote: post #27

This is all ultimately pointless because it's not like the video decoder checks the integrity of its own code or the CPU running it or the compiler that compiled it or that the OS it was tested against is actually running. (Reflections on trusting trust.) Nothing actually cares about secure boot or end-to-end code validation; Apple doesn't even include equipment on their mainboards to do this anymore. Meanwhile, if y…

"Intel's just using Hollywood's fear of piracy" DRM has very little to do with piracy. Hollywood know perfectly well that DRM will not stop a determined pirate and a movie only has to be ripped once to be pirated indefinitely. It's about control. It's about the studios always having a seat at the bargaining table when new products/devices are being floated. They fear becoming a commodity supplier.

DRM is absolutely to do with piracy, that's the whole point of the technology.

Of course Hollywood knows that any given DRM scheme will be broken at some point. How much they care about this depends a lot on what exactly "at some point" really means. Almost all money from movie sales comes in a spike when the movie is first release, hardly any movies go on to become long-term cult classics that people are still buying years later. If a DRM scheme is so good that it takes three months to crack once disks hit the street, from the movie studios perspectives that's a huge win because during the movie's peak people had to cough up the money to buy it or put up with some truly crappy low quality version.

The same economics holds for other things like video games. Nobody cares if you beat the DRM on a game that's five years old.

So the real question is, can DRM give studios and other content creators such a window of time? The results are mixed. Sometimes the answer has been yes. Other times the answer has been no. It's complicated and depends on a lot of fiddly things.

Re: Why Rosyna Can't Take a Movie Screenshot

#66

Post by juliangregorian »

buro9 wrote: post #37

My partner is an academic, a lecturer in film theory. She watches a lot of films, and needs to make a lot of short clips for her lectures, and to take a lot of screenshots for her papers. This task is becoming increasingly difficult as time goes by. The most reliable method (for her skill level) is now to rip DVDs, removing various bits of protection, before playing the film using VLC on Windows and using VLC to take…

Curious why VLC/screenshot doesn't work on Mac?

Re: Why Rosyna Can't Take a Movie Screenshot

#67

Post by mike_hearn »

kuschku wrote: post #28
rando289 wrote: post #23

Earlier quoted context omitted.

Dan would later learn that there was a time when anyone could have debugging tools. There were even free debugging tools available on CD or downloadable over the net. But ordinary users started using them to bypass copyright monitors, and eventually a judge ruled that this had become their principal use in actual practice. This meant they were illegal; the debuggers' developers were sent to prison. https://www.gnu.or…

This actually already happened, with the judge that declared wget as hacking tool...

It happened decades ago, games consoles have always worked this way. Games consoles are not quite a dystopian disaster ...

Re: Why Rosyna Can't Take a Movie Screenshot

#68

Post by mike_hearn »

MichaelGG wrote: post #22
thatone wrote: post #14

Earlier quoted context omitted.

More importantly, why would software be required to engage in all activity by piping through such a hardware interface. I would expect that open source alternatives and virtualization could easily bypass its necessity. At first glance, dumping the contents of any source media, or capturing network streams properly, should readily provide the raw, unencrypted content data, which is then decoded by an application that…

The goal is that the decoding is done by trusted hardware, not by software keys. So you can run VMs and open source, but they won't have the keys to decrypt the content. Same deal with HDCP, where PCIe is treated as an unsafe bus, so data goes encrypted from the kernel to the GPU to the display device (something like that). It's also why sometimes people have trouble watching Netflix or so on, because some part fails…

The goal of DRM is not to kill piracy 100% and anything else is abject failure, it's to raise the cost of engaging in piracy to the point where just buying the movie seems easier and cheaper.

Re: Why Rosyna Can't Take a Movie Screenshot

#69

Post by mike_hearn »

anon4 wrote: post #36
rewqfdsa wrote: post #21

Earlier quoted context omitted.

> the contents of any source media...should readily provide the raw, unencrypted content data Once this crap becomes ubiquitous, why would companies ship unencrypted bits at all? They could send files encrypted with all the major OEM "protected content" keys. If you're running on non-supported hardware, well, sucks to be you, pirate. I imagine it's rather difficult to extract the private key from DRM hardware. In the…

They already did that, twice. First with DVD which used a weak scrambling scheme that was defeated, then with BluRay which used strong encryption, but people were able to extract the keys. The problem with that scheme is that once any one key leaks, you can't do anything about it, especially not if the key is burned in your CPU. You can't expect everyone to go buy a new Intel CPU each time someone manages to extract…

DVD encryption was the same strength as BluRay, cryptographically. The difference between them are twofold:

1) For DVDs there were only a handful of player keys, like less than 30 if I recall correctly. Once they were all leaked the system was broken forever. AACS as used on BluRay has so many keys and such efficient revocation that each player can have its own key.

2) The BluRay designers realised that AACS by itself was insufficient because it takes time to revoke a key, and if they leak faster than they can be revoked the total quantity doesn't matter much. So they did BD+ as well, which is basically a kind of band-aid to detect emulators using stolen keys.

BluRay security has definitely been more effective than DVD security, especially in its earlier days, but the leak of the HDCP master key was pretty fatal, and eventually (all proprietary) emulators got good enough that BD+ programs couldn't really tell them apart from legit licensed players.

Re: Why Rosyna Can't Take a Movie Screenshot

#70

Post by DanBC »

mike_hearn wrote: post #65
ris wrote: post #61

Earlier quoted context omitted.

"Intel's just using Hollywood's fear of piracy" DRM has very little to do with piracy. Hollywood know perfectly well that DRM will not stop a determined pirate and a movie only has to be ripped once to be pirated indefinitely. It's about control. It's about the studios always having a seat at the bargaining table when new products/devices are being floated. They fear becoming a commodity supplier.

DRM is absolutely to do with piracy, that's the whole point of the technology. Of course Hollywood knows that any given DRM scheme will be broken at some point . How much they care about this depends a lot on what exactly "at some point" really means. Almost all money from movie sales comes in a spike when the movie is first release, hardly any movies go on to become long-term cult classics that people are still buyi…

DRM is tied to formats, not to movie releases. Your timin argument is odd when you consider that they still release movies on DVD with a thoroughly broken DRM system.

> The same economics holds for other things like video games. Nobody cares if you beat the DRM on a game that's five years old.

Yes, they do. Japanese game companies wanted to make it illegal to sell games to the second user market; MAME rom sites are routinely shut down.

Disney initially resisted releasing films on VHS because they would not be able to extract a charge from everyone in the room watching the movie. Disney uas investigated a bunch of different rights protection mechanisms. They invented video cassettes that had a ratchet meaning they could only be watched once and needed to be sent back to a factory to be rewound. They invented a DVD that oxidized in contact with air. It would be sent to you in special packaging. You had about 48 hours after opening the package before the disc degrades.

Early music players had weird schemes - one digital copy; weird software needed to load music to the device.

All of these are about controlling how the consumer uses the product. The intent might be to make casual piracy harder, but the effect is to make life really freaking hard for honest people.

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