4 ms·

Copy Protection in Modern Microcontrollers (2001)

40 points by csh0 5y ago

userbinator 5y ago
"MCU break" services start at just under 1k$ and go up to a few k$ USD, the last time I checked. They're mostly based in the Far East (I'm not surprised at the author of this page) and while a lot of people may think "IP theft", they're very useful for right-to-repair, although at the higher end of the price range; if you have some old very expensive machinery to which the original company has long discontinued support or even no longer exists, the price doesn't seem so high anymore.
- mikkohypponen 5y ago
  Some examples of companies working in MCU Break: https://itresearch.en.ecplaza.net/ https://itresearch.en.ecplaza.net/ https://www.ecvv.com/product/2944823.html https://www.ecvv.com/product/2944823.html https://icchip.weebly.com/ https://icchip.weebly.com/
- randombits0 5y ago
  Here’s where copyright and “IP” break down. If I bought the system, I bought the code. Functional expressions are not copyrightable. If I own a copy of the code you wrote, I am reasonably allowed to extract those purely functional expressions into my own work. Purely creative expressions are still protected by copyright. (This is why you cannot copyright an encryption key.) When no “owner” exists, the licensing agreement is no longer valid. Copyright is a different issue. See above.
  - deleted 5y ago
    [deleted]
- jevoten 5y ago
  > IP theft If the code is covered by patents, extracting it doesn't give you anything that reading the public patent wouldn't (if the patent was written as it should have been, to inform, and not obfuscated or ran through incomprehensible legal jargon). And if it's a trade secret, then you relinquished it the moment you sold objects containing it. Though I realize DRM/anti-reverse engineering laws are trying to take away our right to examine how stuff works, they are absurdly immoral laws, and breaking them should never be described as "theft".
0xTJ 5y ago
You shouldn't completely rely on the code you put out into the world in devices remaining secret. A sufficiently capable adversary will likely eventually get your data. Whether you're talking about a $0.30 MCU with the lock e-fuse programmed, or a several-hundred-dollar (or more) SoC with triple-redundant power-management/security cores booting using unit-unique payload decryption keys burned into security fuses, the adversary might be able to get what you're trying to protect. How paranoid you want to be about readout protection will vary depending on your goals. If you want to do a decent job blocking reverse engineering of a product to impeded clones being produced, the lock bit might do the trick.
- amelius 5y ago
  Casting your PCB in resin might do the trick.
  - slabity 5y ago
    Acetone and a cotton swab will make quick work of that.
    - ddingus 5y ago
      Saw a design with battery / super capacitor and light sensor to deal with that. On light detect, kill power to volitile RAM and or wipe non volatile storage. Cat n mouse game level up! Now it has to be done in the dark, or using a light wavelength invisible to the sensor.
      - userbinator 5y ago
        or using a light wavelength invisible to the sensor. ...such as x-rays. There are some highly secure (and expensive) cryptoprocessors which detect those too, but since security is their primary function, the effort is worth it. Otherwise you just end up spending more on protecting something of relatively little value that the cloners will reimplement in some other way anyway.

40 points by csh0 5y ago

"MCU break" services start at just under 1k$ and go up to a few k$ USD, the last time I checked. They're mostly based in the Far East (I'm not surprised at the author of this page) and while a lot of people may think "IP theft", they're very useful for right-to-repair, although at the higher end of the price range; if you have some old very expensive machinery to which the original company has long discontinued support or even no longer exists, the price doesn't seem so high anymore.

mikkohypponen 5y ago
Some examples of companies working in MCU Break: https://itresearch.en.ecplaza.net/ https://itresearch.en.ecplaza.net/ https://www.ecvv.com/product/2944823.html https://www.ecvv.com/product/2944823.html https://icchip.weebly.com/ https://icchip.weebly.com/
randombits0 5y ago
Here’s where copyright and “IP” break down. If I bought the system, I bought the code. Functional expressions are not copyrightable. If I own a copy of the code you wrote, I am reasonably allowed to extract those purely functional expressions into my own work. Purely creative expressions are still protected by copyright. (This is why you cannot copyright an encryption key.) When no “owner” exists, the licensing agreement is no longer valid. Copyright is a different issue. See above.
- deleted 5y ago
  [deleted]
jevoten 5y ago
> IP theft If the code is covered by patents, extracting it doesn't give you anything that reading the public patent wouldn't (if the patent was written as it should have been, to inform, and not obfuscated or ran through incomprehensible legal jargon). And if it's a trade secret, then you relinquished it the moment you sold objects containing it. Though I realize DRM/anti-reverse engineering laws are trying to take away our right to examine how stuff works, they are absurdly immoral laws, and breaking them should never be described as "theft".

0xTJ 5y ago

You shouldn't completely rely on the code you put out into the world in devices remaining secret. A sufficiently capable adversary will likely eventually get your data. Whether you're talking about a $0.30 MCU with the lock e-fuse programmed, or a several-hundred-dollar (or more) SoC with triple-redundant power-management/security cores booting using unit-unique payload decryption keys burned into security fuses, the adversary might be able to get what you're trying to protect. How paranoid you want to be about readout protection will vary depending on your goals. If you want to do a decent job blocking reverse engineering of a product to impeded clones being produced, the lock bit might do the trick.

amelius 5y ago
Casting your PCB in resin might do the trick.
- slabity 5y ago
  Acetone and a cotton swab will make quick work of that.
  - ddingus 5y ago
    Saw a design with battery / super capacitor and light sensor to deal with that. On light detect, kill power to volitile RAM and or wipe non volatile storage. Cat n mouse game level up! Now it has to be done in the dark, or using a light wavelength invisible to the sensor.
    - userbinator 5y ago
      or using a light wavelength invisible to the sensor. ...such as x-rays. There are some highly secure (and expensive) cryptoprocessors which detect those too, but since security is their primary function, the effort is worth it. Otherwise you just end up spending more on protecting something of relatively little value that the cloners will reimplement in some other way anyway.