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These secure boot systems exist because of DRM protection to media that is mandated by the content companies. Their point is to verify that the whole OS from ke

by exDM69 8y ago

These secure boot systems exist because of DRM protection to media that is mandated by the content companies. Their point is to verify that the whole OS from kernel to userspace can't be modified by 3rd parties (such as you, the owner of the device). It boils down to "no secure boot, no DRM, no Netflix 4k for you". At least this was the case when I was still working with consumer electronics a few years ago.

zeta0134 8y ago
At least in the mobile space, I get the feeling that theft of the device factors in here. A lot of carriers advertise some sort of remote lock + wipe mechanism, which isn't guaranteed to work if the device's bootloader is unlocked, allowing an attacker to bypass the feature before it has a chance to run. I have no idea if that's actually the case (I only worked tangential to a retail store's mobile department) so take that with a grain of salt, that's just what I observed the carriers making a big fuss about on the regular. I don't think that excuses the practice either; I'll always be in favor of being in full control of any hardware I'm supposed to trust with my data, but ofc I realize I'm in the minority there.
- drbawb 8y ago
  I'm totally fine w/ there being a disclaimer on bootloader unlocking, e.g: "Warning! Some security features of your device may not work properly w/ secure boot disabled. Visit foo.com/secure-boot to learn more." To a lesser extent I'm OK w/ bootloader unlocks voiding my warranty, esp. since many of these devices ship w/ permanent fuses whereby writing to the wrong MSRs may brick your device. After all that's how my Moto X (2013) worked: I needed a code from Motorola to unlock the bootloader, which in turn required agreeing to a warranty waiver. What's not OK is having a permanently locked bootloader that guarantees my device will be useless after the carrier decides to stop delivering OTA updates in a year or two.
thaumasiotes 8y ago
> It boils down to "no secure boot, no DRM, no Netflix 4k for you". I really can't say I'm worried about the theoretical inability to stream 4k video to a 5" screen. At that size, 4k is just wasting bandwidth.
- dcow 8y ago
  They're more worried about people ripping the content, not pumping 4k streams to your smartphone.
- mjones72 8y ago
  Netflix streams are usually so compressed that there is a noticeable improvement if you use 4K over 1080p. What you're actually comparing is "blurry 4K" to "blurry 1080p".
  - pedrocr 8y ago
    And that's if they give you 1080p. I cancelled Netflix because they rolled out price hikes and yet even dominant platforms like Chrome on Windows only get blurry 720p which is completely unacceptable these days: https://help.netflix.com/en/node/23742 https://help.netflix.com/en/node/23742
- izacus 8y ago
  You maybe aren't, but manufacturers of that hardware will get negative PR if their Netflix only runs at 480p - so they comply to limitations. Is it really that hard to think a bit farther than yourself?
  - dpwm 8y ago
    I'm not so sure as many will notice it on a device with a 5" screen. By my calculations, assuming an angular resolution of the eye of about 1 arcminute[0] and holding the device at 300mm, I get about 700 lines as the upper limit of the human eye. [1] So really there should be no benefit for anything above 720p. There may be other factors relating to scaling and compression that might make higher resolutions on small devices look better, but it's definitely of diminishing returns. [0] https://en.wikipedia.org/wiki/Naked_eye https://en.wikipedia.org/wiki/Naked_eye [1] https://gist.github.com/dpwm/af467dff758d6f0c5810a2cf902bbf8b https://gist.github.com/dpwm/af467dff758d6f0c5810a2cf902bbf8...
    - izacus 8y ago
mfukar 8y ago
> Their point is to verify that the whole OS from kernel to userspace can't be modified by 3rd parties (such as you, the owner of the device). Or, _perhaps_, someone who doesn't own the device.
minipci1321 8y ago
> These secure boot systems exist because of DRM protection to media that is mandated by the content companies. That statement sounds too simplified. How about non-approved images pumping power upstream above regulatory limit on RF? Or overclocking the CPU? Or reporting all keystrokes to a place of your choice? Would you, as a manufacturer of the device, like to make that easily possible? > Their point is to verify that the whole OS from kernel to userspace can't be modified by 3rd parties (such as you, the owner of the device). What makes it impossible is not the secure boot but the fact that the _unauthorized_ 3rd parties don't have the keys for signing stages of the images. Some owners of some secure-boot devices, do have keys and sign their images. One example: a telecom operator, owner of its park of the set-top box decoders, does that. Secure boot can be made to allow several/many authorized keys.
- dcow 8y ago
  If I don't own the device then why am I paying for it?
  - minipci1321 8y ago
    Unclear what you had in mind. I'll assume you were speaking about your own secure-booting mobile phone that you paid full price and now would like to be able to reflash? I am not sure what to tell you. The situation pre-dates the secure boot. If I recall correctly, Iiyama monitors were known to be unrepairable because the manufacturer always refused to release schematics. It did not prevent their extreme popularity. As an end-consumer, I support very much the freedom to change any products I own, the way I want. I once replaced ball bearings in the drum of my washing machine -- you get the idea. As a person authorizing a product that can potentially emit unhealthy or unsafe levels of RF, or a parent of teenagers using social media, or a developer of medical applications intended for mobile phone... I am none of that, but I guess I would have a very different opinion.
    - CogitoCogito 8y ago
      > As a person authorizing a product that can potentially emit unhealthy or unsafe levels of RF, or a parent of teenagers using social media, or a developer of medical applications intended for mobile phone... I am none of that, but I guess I would have a very different opinion. Let's be honest and accept it's just about money and control to the makers of these devices. They will bring reasons such as these in their defense, but really they just want to keep the user from being in control of their device and e.g. making tracking them more difficult. I mean there have probably been tens of thousands of roms flashed on different devices. How many of them have emitted unhealthy levels of RF? And parents could retain the ability to flash their devices without giving that ability to their children. The reasons really just don't hold any water imo.
JoshuaAshton 8y ago
DRM restrictions like this are always a joke - HDCP was a great one. Also, I doubt many people are going to be getting their Netflix captures/dumps from an Android device anyway so its a useless restriction, they'll be doing it on a PC where this cannot be enforced. There are also things such as Google Pay/Banking Apps that don't like it if you are using a custom ROM (although this is root based) it can be bypassed easily using Magisk. There will always be away round frivolous DRM attempts, even Denuvo and it really just hurts consumer choice and device freedom.
- gruez 8y ago
  >Also, I doubt many people are going to be getting their Netflix captures/dumps from an Android device anyway so its a useless restriction, they'll be doing it on a PC where this cannot be enforced Not for Netflix 4K, which requires SGX capable CPUs to play.
  - maxyme 8y ago
    And windows 10 anniversary update, Microsoft Edge, Direct Play 2.0 support (which can only be found on recent graphics cards or 7th gen Intel integrated and only works over certain video outputs). For example I have a 7th gen Intel cpu, I can boot into windows and use Edge, download the media extensions, update my graphic drivers, but I still can't get 4k Netflix because my GPU is a year or so older than AMF supports for Direct Play 2.0 and additionally I have my 4k 10bit color monitor using Display port for the higher bandwidth. From what I've read at this time Display port isn't even supported with Direct Play 2.0 by AMD. Basically it's such a pain in the ass, you aren't going to have 4k Netflix on PC, possibly even if you try...
    - thedailymail 8y ago
      Just wait. Human-made designs are susceptible to human-made hacks.
    - SSLy 8y ago
      Yet there are 4K rips sourced from Netflix being shared on pirate sites.
wyldfire 8y ago
> These secure boot systems exist because of DRM protection to media that is mandated by the content companies That might be an effect but I doubt it's the cause. Signed bootloader's have been around longer than Android and longer than the Netflix app. They were originally introduced to do things like -- protect the device subsidy lock, prevent customers from flashing their phone with invalid or buggy firmware, prevent modification of radio functions (maybe required for FCC license?). Nowadays they're useful for more than just DRM too. I'd guess that since the owner unlocks the phone functionality, they are a big disincentive to thefts.
paulie_a 8y ago
> no DRM, no Netflix 4k for you". No drm is a feature, and fine I'll just pirate it, it's easier anyways.
- deleted 8y ago
  [deleted]
01100011 8y ago
This. Embedded guy formerly involved with media devices here, and this is 100% correct. The secrecy involved in content protection is far beyond anything I've seen while working as a military contractor. At some shops, developers don't even get unlocked bootloaders. You get a device with a bootloader which must be cryptographically unlocked and allowed to boot a limited number of times before needing to be unlocked again. You also have to sign your life away if you ever divulge any confidential details. Chances are though, that you won't even be exposed to the juiciest details because only a select group of senior devs get to see that stuff. Working with content protection companies like NDS or Nagravision is frankly maddening. I know a guy who has his design rejected(because they review your entire system design before certification) and they couldn't even tell him why they rejected his design.

by exDM69 8y ago

zeta0134 8y ago

At least in the mobile space, I get the feeling that theft of the device factors in here. A lot of carriers advertise some sort of remote lock + wipe mechanism, which isn't guaranteed to work if the device's bootloader is unlocked, allowing an attacker to bypass the feature before it has a chance to run. I have no idea if that's actually the case (I only worked tangential to a retail store's mobile department) so take that with a grain of salt, that's just what I observed the carriers making a big fuss about on the regular. I don't think that excuses the practice either; I'll always be in favor of being in full control of any hardware I'm supposed to trust with my data, but ofc I realize I'm in the minority there.

drbawb 8y ago
I'm totally fine w/ there being a disclaimer on bootloader unlocking, e.g: "Warning! Some security features of your device may not work properly w/ secure boot disabled. Visit foo.com/secure-boot to learn more." To a lesser extent I'm OK w/ bootloader unlocks voiding my warranty, esp. since many of these devices ship w/ permanent fuses whereby writing to the wrong MSRs may brick your device. After all that's how my Moto X (2013) worked: I needed a code from Motorola to unlock the bootloader, which in turn required agreeing to a warranty waiver. What's not OK is having a permanently locked bootloader that guarantees my device will be useless after the carrier decides to stop delivering OTA updates in a year or two.

thaumasiotes 8y ago

> It boils down to "no secure boot, no DRM, no Netflix 4k for you". I really can't say I'm worried about the theoretical inability to stream 4k video to a 5" screen. At that size, 4k is just wasting bandwidth.

dcow 8y ago
They're more worried about people ripping the content, not pumping 4k streams to your smartphone.
mjones72 8y ago
Netflix streams are usually so compressed that there is a noticeable improvement if you use 4K over 1080p. What you're actually comparing is "blurry 4K" to "blurry 1080p".
- pedrocr 8y ago
  And that's if they give you 1080p. I cancelled Netflix because they rolled out price hikes and yet even dominant platforms like Chrome on Windows only get blurry 720p which is completely unacceptable these days: https://help.netflix.com/en/node/23742 https://help.netflix.com/en/node/23742
izacus 8y ago
You maybe aren't, but manufacturers of that hardware will get negative PR if their Netflix only runs at 480p - so they comply to limitations. Is it really that hard to think a bit farther than yourself?
- dpwm 8y ago
  I'm not so sure as many will notice it on a device with a 5" screen. By my calculations, assuming an angular resolution of the eye of about 1 arcminute[0] and holding the device at 300mm, I get about 700 lines as the upper limit of the human eye. [1] So really there should be no benefit for anything above 720p. There may be other factors relating to scaling and compression that might make higher resolutions on small devices look better, but it's definitely of diminishing returns. [0] https://en.wikipedia.org/wiki/Naked_eye https://en.wikipedia.org/wiki/Naked_eye [1] https://gist.github.com/dpwm/af467dff758d6f0c5810a2cf902bbf8b https://gist.github.com/dpwm/af467dff758d6f0c5810a2cf902bbf8...
  - izacus 8y ago

mfukar 8y ago

> Their point is to verify that the whole OS from kernel to userspace can't be modified by 3rd parties (such as you, the owner of the device). Or, _perhaps_, someone who doesn't own the device.

minipci1321 8y ago

> These secure boot systems exist because of DRM protection to media that is mandated by the content companies. That statement sounds too simplified. How about non-approved images pumping power upstream above regulatory limit on RF? Or overclocking the CPU? Or reporting all keystrokes to a place of your choice? Would you, as a manufacturer of the device, like to make that easily possible? > Their point is to verify that the whole OS from kernel to userspace can't be modified by 3rd parties (such as you, the owner of the device). What makes it impossible is not the secure boot but the fact that the _unauthorized_ 3rd parties don't have the keys for signing stages of the images. Some owners of some secure-boot devices, do have keys and sign their images. One example: a telecom operator, owner of its park of the set-top box decoders, does that. Secure boot can be made to allow several/many authorized keys.

dcow 8y ago
If I don't own the device then why am I paying for it?
- minipci1321 8y ago
  Unclear what you had in mind. I'll assume you were speaking about your own secure-booting mobile phone that you paid full price and now would like to be able to reflash? I am not sure what to tell you. The situation pre-dates the secure boot. If I recall correctly, Iiyama monitors were known to be unrepairable because the manufacturer always refused to release schematics. It did not prevent their extreme popularity. As an end-consumer, I support very much the freedom to change any products I own, the way I want. I once replaced ball bearings in the drum of my washing machine -- you get the idea. As a person authorizing a product that can potentially emit unhealthy or unsafe levels of RF, or a parent of teenagers using social media, or a developer of medical applications intended for mobile phone... I am none of that, but I guess I would have a very different opinion.
  - CogitoCogito 8y ago
    > As a person authorizing a product that can potentially emit unhealthy or unsafe levels of RF, or a parent of teenagers using social media, or a developer of medical applications intended for mobile phone... I am none of that, but I guess I would have a very different opinion. Let's be honest and accept it's just about money and control to the makers of these devices. They will bring reasons such as these in their defense, but really they just want to keep the user from being in control of their device and e.g. making tracking them more difficult. I mean there have probably been tens of thousands of roms flashed on different devices. How many of them have emitted unhealthy levels of RF? And parents could retain the ability to flash their devices without giving that ability to their children. The reasons really just don't hold any water imo.

JoshuaAshton 8y ago

DRM restrictions like this are always a joke - HDCP was a great one. Also, I doubt many people are going to be getting their Netflix captures/dumps from an Android device anyway so its a useless restriction, they'll be doing it on a PC where this cannot be enforced. There are also things such as Google Pay/Banking Apps that don't like it if you are using a custom ROM (although this is root based) it can be bypassed easily using Magisk. There will always be away round frivolous DRM attempts, even Denuvo and it really just hurts consumer choice and device freedom.

gruez 8y ago
>Also, I doubt many people are going to be getting their Netflix captures/dumps from an Android device anyway so its a useless restriction, they'll be doing it on a PC where this cannot be enforced Not for Netflix 4K, which requires SGX capable CPUs to play.
- maxyme 8y ago
  And windows 10 anniversary update, Microsoft Edge, Direct Play 2.0 support (which can only be found on recent graphics cards or 7th gen Intel integrated and only works over certain video outputs). For example I have a 7th gen Intel cpu, I can boot into windows and use Edge, download the media extensions, update my graphic drivers, but I still can't get 4k Netflix because my GPU is a year or so older than AMF supports for Direct Play 2.0 and additionally I have my 4k 10bit color monitor using Display port for the higher bandwidth. From what I've read at this time Display port isn't even supported with Direct Play 2.0 by AMD. Basically it's such a pain in the ass, you aren't going to have 4k Netflix on PC, possibly even if you try...
  - thedailymail 8y ago
    Just wait. Human-made designs are susceptible to human-made hacks.
  - SSLy 8y ago
    Yet there are 4K rips sourced from Netflix being shared on pirate sites.

wyldfire 8y ago

> These secure boot systems exist because of DRM protection to media that is mandated by the content companies That might be an effect but I doubt it's the cause. Signed bootloader's have been around longer than Android and longer than the Netflix app. They were originally introduced to do things like -- protect the device subsidy lock, prevent customers from flashing their phone with invalid or buggy firmware, prevent modification of radio functions (maybe required for FCC license?). Nowadays they're useful for more than just DRM too. I'd guess that since the owner unlocks the phone functionality, they are a big disincentive to thefts.

paulie_a 8y ago

> no DRM, no Netflix 4k for you". No drm is a feature, and fine I'll just pirate it, it's easier anyways.

deleted 8y ago
[deleted]

01100011 8y ago

This. Embedded guy formerly involved with media devices here, and this is 100% correct. The secrecy involved in content protection is far beyond anything I've seen while working as a military contractor. At some shops, developers don't even get unlocked bootloaders. You get a device with a bootloader which must be cryptographically unlocked and allowed to boot a limited number of times before needing to be unlocked again. You also have to sign your life away if you ever divulge any confidential details. Chances are though, that you won't even be exposed to the juiciest details because only a select group of senior devs get to see that stuff. Working with content protection companies like NDS or Nagravision is frankly maddening. I know a guy who has his design rejected(because they review your entire system design before certification) and they couldn't even tell him why they rejected his design.