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Oh no. You're assuming the hardware field is about simply producing hardware and that's it. He taught me that they (a) know R&D cost a lot, (b) assume patent tr

Oh no. You're assuming the hardware field is about simply producing hardware and that's it. He taught me that they (a) know R&D cost a lot, (b) assume patent trolls will hit them constantly so they obfuscate the hell out of everything anyway, and (c) therefore steal each others stuff in whatever way they can while not advertising specifics on how it works to avoid patent trolls. The result was all kinds of hardware companies were ripping off all kinds of others with constant remixes on top of a cat and mouse game for security that makes software security look lame (my impression). He said competitors even sometimes cloned the best stuff down to the transistors where even he had trouble telling the fakes of his company's parts. The defense was to make it hard to copy. They did crazy tricks on the digital level. He did stuff on analog level as well since his area was mixed-signal. His favorite technique was splitting the function between digital and analog since so few analog people existed to RE that stuff. He pointed out that digital tools couldn't even see analog stuff. Top that off with obfuscation to wild degrees. We stopped hearing from him after he changed employers, though. Some of the things he predicted came true. An example was the A2 backdoor which was the kind of analog subversion he told us happened regularly. Another included a fab compromise which his trust model got me thinking about and predicting in the abstract. That the guys statements started coming true too often in various ways among hardware people and in CompSci papers means I'm inclined to believe him that hardware is a scheming a business as he claimed it to be.

lisper 10y ago
OK... but none of that sounds like it would result in deliberately introducing security flaws of the sort under discussion here. Let's not forget the context of this discussion: "Some researchers have even speculated, especially since the disclosures by Edward Snowden, that commercial hardware sources could be subtly manipulated to make the codes easier to break by the U.S. National Security Agency or others." [Emphasis added] Obviously such attacks are possible, but are they likely? I can see how the cat-and-mouse game of IP protection would lead to all kinds of dirty tricks, but what would be the profit in introducing a backdoor that could be leveraged to break crypto or an RNG?
- Cyph0n 10y ago
  I remember reading that the Linux kernel does not use Intel's hardware RNG alone for /dev/(u)random precisely because of concerns that Intel has backdoored the RNG.
  - lisper 10y ago
    Yes, that's true, and that is a legitimate concern. I personally would not trust Intel's RNG because it is implemented in a way that deliberately hides some of the underlying implementation in a way that would make it impossible to tell if it's backdoored. That is my original point: it is much harder to tell if hardware has a back door than software.
    - Cyph0n 10y ago
      But does this not provide an example of an intentional backdoor in a hardware RNG? I'm actually going to be diving into the literature on hardware verification, with a focus on how to design IP that can be objectively verified by a third-party. If I find something good, I might even do my PhD on this topic.
      - nickpsecurity 10y ago
        This is the kind of tangential thinking tptacek apparently fell for in the BitBabbler discussion. While they were talking Intel RNG's, I was focusing on the fact that Intel advertises a chip-level backdoor w/ its own TCP/IP stack & MCU that listens even when CPU is shutdown. It's called AMT. That he knew about it but focused on risk of their TRNG when whole chip is backdoored is beyond my understanding. Here it is in case you weren't familiar with its specifics: https://en.wikipedia.org/wiki/Intel_Active_Management_Technology https://en.wikipedia.org/wiki/Intel_Active_Management_Techno... Also, as in my recent reply to lisper, the hooks that make it work are probably in all the chips of any family containing at least one with that technology. That's to reduce mask and production costs. They might be able to remotely activate it but can't know cuz it's a black box. :)
      - 10y ago

lisper 10y ago

OK... but none of that sounds like it would result in deliberately introducing security flaws of the sort under discussion here. Let's not forget the context of this discussion: "Some researchers have even speculated, especially since the disclosures by Edward Snowden, that commercial hardware sources could be subtly manipulated to make the codes easier to break by the U.S. National Security Agency or others." [Emphasis added] Obviously such attacks are possible, but are they likely? I can see how the cat-and-mouse game of IP protection would lead to all kinds of dirty tricks, but what would be the profit in introducing a backdoor that could be leveraged to break crypto or an RNG?

Cyph0n 10y ago
I remember reading that the Linux kernel does not use Intel's hardware RNG alone for /dev/(u)random precisely because of concerns that Intel has backdoored the RNG.
- lisper 10y ago
  Yes, that's true, and that is a legitimate concern. I personally would not trust Intel's RNG because it is implemented in a way that deliberately hides some of the underlying implementation in a way that would make it impossible to tell if it's backdoored. That is my original point: it is much harder to tell if hardware has a back door than software.
  - Cyph0n 10y ago
    But does this not provide an example of an intentional backdoor in a hardware RNG? I'm actually going to be diving into the literature on hardware verification, with a focus on how to design IP that can be objectively verified by a third-party. If I find something good, I might even do my PhD on this topic.
    - nickpsecurity 10y ago
      This is the kind of tangential thinking tptacek apparently fell for in the BitBabbler discussion. While they were talking Intel RNG's, I was focusing on the fact that Intel advertises a chip-level backdoor w/ its own TCP/IP stack & MCU that listens even when CPU is shutdown. It's called AMT. That he knew about it but focused on risk of their TRNG when whole chip is backdoored is beyond my understanding. Here it is in case you weren't familiar with its specifics: https://en.wikipedia.org/wiki/Intel_Active_Management_Technology https://en.wikipedia.org/wiki/Intel_Active_Management_Techno... Also, as in my recent reply to lisper, the hooks that make it work are probably in all the chips of any family containing at least one with that technology. That's to reduce mask and production costs. They might be able to remotely activate it but can't know cuz it's a black box. :)
    - 10y ago