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"no DRM solution is available on Linux" DRM is basically digital signing w/encryption right ? Linux doesn't have that ?

by lyndonh 13y ago

vidarh 13y ago
It's decryption of encrypted contents with a key that you're not meant to have access to, and with measures to try to prevent you from accessing the decoded video and audio on its way to the screen/speakers, despite the fact that the key is on your system and it's being played back via hardware that's physically under your control. It's a bit like trying to stop a sieve from leaking with your fingers. The only way of making it sort-of, maybe achieve anything in software is through obscuring the key and decrypted data sufficiently to make it more effort than it is worth. This means the DRM implementations are all closed source, and Linux ports are pretty much bottom of the priority list of any of the companies providing DRM solutions, not least because it gets massively harder to lock down access to the data on a system where tons of people know how to rebuild the kernel and modify drivers and otherwise try to intercept it.
- lyndonh 13y ago
  "... it gets massively harder to lock down access to the data on a system where tons of people know how to rebuild the kernel and modify drivers and otherwise try to intercept it." Because proprietary systems never get cracked; and it always takes more than one person to do it. For example, geohot. My point is that Linux DRM is possible. But all DRM sucks anyway, because ultimately to lock down the system implementors choose to reduce the number of devices that can operate with it and sooner or later it's just one or two devices.
  - vidarh 13y ago
    Of course the get cracked, but as you say: all DRM sucks anyway. So they set a bar based on how difficult they can make it to circumvent vs. market share. In that calculation it becomes easy to decide to ignore Linux - small desktop userbase and a much harsher environment makes it extremely unattractive. It's never about locking it down fully - they're not quite stupid enough to believe they can prevent copying. After all they know perfectly well that most torrents are not originating from copies ripped by average consumers. DRM is about a perceived tradeoff between the cost of DRM and how much copying they can stop by making it too cumbersome or difficult for a reasonable proportion of regular users. It doesn't even necessarily have much to do with reality, but just as much to do with sheer fear.
dsr_ 13y ago
DRM is handing a ciphertext, a decryptor, and keys over to someone else and asking them to use it only in the way that you want them to use it. (It's not signed because nobody cares whether the information is authentic or not.) Once you have bought into the rigmarole that this can somehow be effective, you have to test and support various platforms. Doing that for Windows is cost-effective, doing it for MacOS is less so, and doing it for anything smaller is not a money-making proposition. Of course, if you could add 2 + 2 to get 4 in the first place, you would use an open standard and be able to sell your media to everyone.
- jimhefferon 13y ago
  > DRM is handing a ciphertext, a decryptor, and keys over to someone else and asking them to use it only in the way that you want them to use it. I think I have a new .sig.
  - npsimons 13y ago
    I've always liked this summary of DRM from someone on slashdot: Very, very simply, here is the premise behind DRM. 1. I know a secret 2. I want to tell you the secret 3. I don't want you to tell anyone else the secret 4. I don't trust you Perhaps you can see now why there's no solution to that scenario. Another good short one: DRM 'manages access' in the same way that jail 'manages freedom.'
    - lloeki 13y ago
      Simpler: since you need the key to view the content, the only security scheme possible is through obscurity of the key or the decryptor. Hence anyone with the appropriate flashlight can dispell the darkness. Also, analog hole.

"no DRM solution is available on Linux" DRM is basically digital signing w/encryption right ? Linux doesn't have that ?

by lyndonh 13y ago

"no DRM solution is available on Linux" DRM is basically digital signing w/encryption right ? Linux doesn't have that ?

It's decryption of encrypted contents with a key that you're not meant to have access to, and with measures to try to prevent you from accessing the decoded video and audio on its way to the screen/speakers, despite the fact that the key is on your system and it's being played back via hardware that's physically under your control. It's a bit like trying to stop a sieve from leaking with your fingers. The only way of making it sort-of, maybe achieve anything in software is through obscuring the key and decrypted data sufficiently to make it more effort than it is worth. This means the DRM implementations are all closed source, and Linux ports are pretty much bottom of the priority list of any of the companies providing DRM solutions, not least because it gets massively harder to lock down access to the data on a system where tons of people know how to rebuild the kernel and modify drivers and otherwise try to intercept it.

lyndonh 13y ago
"... it gets massively harder to lock down access to the data on a system where tons of people know how to rebuild the kernel and modify drivers and otherwise try to intercept it." Because proprietary systems never get cracked; and it always takes more than one person to do it. For example, geohot. My point is that Linux DRM is possible. But all DRM sucks anyway, because ultimately to lock down the system implementors choose to reduce the number of devices that can operate with it and sooner or later it's just one or two devices.
- vidarh 13y ago
  Of course the get cracked, but as you say: all DRM sucks anyway. So they set a bar based on how difficult they can make it to circumvent vs. market share. In that calculation it becomes easy to decide to ignore Linux - small desktop userbase and a much harsher environment makes it extremely unattractive. It's never about locking it down fully - they're not quite stupid enough to believe they can prevent copying. After all they know perfectly well that most torrents are not originating from copies ripped by average consumers. DRM is about a perceived tradeoff between the cost of DRM and how much copying they can stop by making it too cumbersome or difficult for a reasonable proportion of regular users. It doesn't even necessarily have much to do with reality, but just as much to do with sheer fear.

dsr_ 13y ago

DRM is handing a ciphertext, a decryptor, and keys over to someone else and asking them to use it only in the way that you want them to use it. (It's not signed because nobody cares whether the information is authentic or not.) Once you have bought into the rigmarole that this can somehow be effective, you have to test and support various platforms. Doing that for Windows is cost-effective, doing it for MacOS is less so, and doing it for anything smaller is not a money-making proposition. Of course, if you could add 2 + 2 to get 4 in the first place, you would use an open standard and be able to sell your media to everyone.

jimhefferon 13y ago
> DRM is handing a ciphertext, a decryptor, and keys over to someone else and asking them to use it only in the way that you want them to use it. I think I have a new .sig.
- npsimons 13y ago
  I've always liked this summary of DRM from someone on slashdot: Very, very simply, here is the premise behind DRM. 1. I know a secret 2. I want to tell you the secret 3. I don't want you to tell anyone else the secret 4. I don't trust you Perhaps you can see now why there's no solution to that scenario. Another good short one: DRM 'manages access' in the same way that jail 'manages freedom.'
  - lloeki 13y ago
    Simpler: since you need the key to view the content, the only security scheme possible is through obscurity of the key or the decryptor. Hence anyone with the appropriate flashlight can dispell the darkness. Also, analog hole.