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It's not just an issue for big corporations and their proprietary software and DRM, but also has serious implications for the free and open source hardware comm

It's not just an issue for big corporations and their proprietary software and DRM, but also has serious implications for the free and open source hardware community, especially the infosec hackers. To begin with: While it's not realistic to make secure hardware (let's say, a OpenPGP/X.509/Bitcoin Wallet security token) that can be 100% independently verified and free from all backdoors, but still, relatively speaking, FPGAs are generally a better and more secure option as a hardware platform than microcontrollers (for example, see the talk [0] by Peter Todd on Bitcoin hardware wallet and pitfalls of general-purpose microcontrolles), because of three advantages: * It's possible to implement custom security protections at a lower level than accepting whatever is provided by a microcontroller or implementing it in more vulnerable software. * Many microcontrollers can be copied easily, but FPGAs are often used to run sensitive bitstream that contains proprietary hardware/software, manufacturers generally provide better security protections, such as verification and encryption, against data extraction (read: OpenPGP private key) and manipulation attacks. * Most "secure" microcontrollers are guarded under heavy NDAs, while they are commercially available (and widely used in DRM systems), but it's essentially useless for the FOSS community. On the other hand, because the extensive use of FPGA in commercial systems, security is NDA-free for many FPGAs. It's often the best (or the only option) that provides the maximum transparency - not everything can be audited, sure, but the other option is using a "secure" blackbox ASIC, which is a total blackbox. Unfortunately, nothing is foolproof, manufacturers leave secret debug interfaces, cryptographic implementations have vulnerabilities, etc. Hardware security is a hard problem - 100% security and independent verification is impossible, making it harder to attack is the objective, but it's worse than software - once a bug is discovered and published, the cost of an attack immediately becomes 0, and it cannot be patched. We can only hope that the increased independent verification, like the researchers behind this paper, can somewhat reduce these problems systematically. [0] https://www.youtube.com/watch?v=r1qBuj_sco4 https://www.youtube.com/watch?v=r1qBuj_sco4

eqvinox 7y ago
The way to protect secure hardware tokens is not bitstream encryption, it's tamper protection. You store the key material in SRAM that is erased when the device detects any attempt at manipulating. If your Bitcoin Wallet or whatever token is affected by this, it was IMHO badly designed to begin with, since apparently it was relying on an AES-CBC bitstream encryption scheme. That should've been a red flag even if it wasn't broken.
- segfaultbuserr 7y ago
  > The way to protect secure hardware tokens is not bitstream encryption, it's tamper protection. You store the key material in SRAM that is erased when the device detects any attempt at manipulating. You need both. First, make all external storage (that hold keys, firmware, configurations) unreadable to everything else besides the main processor itself. Also, in the ideal world, implement tamper detection, in most HSMs there are tamper detections, but unfortunately, the world is not ideal, in the FOSS world, I don't see anything that uses tamper detection, developing an open source tamper detection is something has great value to the community, yet, I don't see it happening at anytime soon. Also, the majority of security token/hardware have no tamper detection - SIM cards, bank cards, OpenPGP cards (Yubikeys, Nitrokeys), smartphones, they only depend on encrypting external storage and/or restrict the access of the secret inside a chip to maintain security. In practice, they still have an above-average security level, it clears shows tamper protection is not the only way to protection the hardware, although it's less effective and occasionally something is going to be broken, to be sure. This specific FPGA bitstream encryption vulnerability may be a non-issue, as pointed out by the critics, relying on external storage is not a good idea to begin with, better to burn everything inside the FPGA. My point is that FPGAs are the only platform to implement FOSS security hardware in the most (relatively) transparent and secure manner, yet, the recent discoveries of FPGAs vulnerabilities indicates they are much less secure than expected, and it's only the tip of an iceberg. If external bitstream encryption has cryptographic vulnerabilities, what comes next? More broken cryptos that allow you to read an internal key?
  - eqvinox 7y ago
    Moving your data inside a device not easily accessible is tamper protection too.

eqvinox 7y ago

The way to protect secure hardware tokens is not bitstream encryption, it's tamper protection. You store the key material in SRAM that is erased when the device detects any attempt at manipulating. If your Bitcoin Wallet or whatever token is affected by this, it was IMHO badly designed to begin with, since apparently it was relying on an AES-CBC bitstream encryption scheme. That should've been a red flag even if it wasn't broken.

segfaultbuserr 7y ago
> The way to protect secure hardware tokens is not bitstream encryption, it's tamper protection. You store the key material in SRAM that is erased when the device detects any attempt at manipulating. You need both. First, make all external storage (that hold keys, firmware, configurations) unreadable to everything else besides the main processor itself. Also, in the ideal world, implement tamper detection, in most HSMs there are tamper detections, but unfortunately, the world is not ideal, in the FOSS world, I don't see anything that uses tamper detection, developing an open source tamper detection is something has great value to the community, yet, I don't see it happening at anytime soon. Also, the majority of security token/hardware have no tamper detection - SIM cards, bank cards, OpenPGP cards (Yubikeys, Nitrokeys), smartphones, they only depend on encrypting external storage and/or restrict the access of the secret inside a chip to maintain security. In practice, they still have an above-average security level, it clears shows tamper protection is not the only way to protection the hardware, although it's less effective and occasionally something is going to be broken, to be sure. This specific FPGA bitstream encryption vulnerability may be a non-issue, as pointed out by the critics, relying on external storage is not a good idea to begin with, better to burn everything inside the FPGA. My point is that FPGAs are the only platform to implement FOSS security hardware in the most (relatively) transparent and secure manner, yet, the recent discoveries of FPGAs vulnerabilities indicates they are much less secure than expected, and it's only the tip of an iceberg. If external bitstream encryption has cryptographic vulnerabilities, what comes next? More broken cryptos that allow you to read an internal key?
- eqvinox 7y ago
  Moving your data inside a device not easily accessible is tamper protection too.