4 ms·

Would you mind elaborating on that? My understanding is from a verification point of view, the Librem 5 is functionally at the absolute top-tier in terms of OpS

by qchris 6y ago

Would you mind elaborating on that? My understanding is from a verification point of view, the Librem 5 is functionally at the absolute top-tier in terms of OpSec concerns, with everything from the bootloader up being open and customized, full disk encryption available, and the only binary blobs (I think on the modem?) being completely sandboxed. Are there additional concerns, and what kind of solutions do they currently use that do meet those needs?

seba_dos1 6y ago
You can even set up a secure boot chain with your own encryption keys, see: https://boundarydevices.com/high-assurance-boot-hab-i-mx8m-edition/ https://boundarydevices.com/high-assurance-boot-hab-i-mx8m-e... (it's a tutorial for a board that uses SoC from the same family as the Librem 5)
atat7024 6y ago
The Librem 5 is not as open or libre as its marketing has tried to insinuate, simply having its binary blob signed and validated firmware saved in write-protected read-only memory and loaded by a secondary coprocessor to exploit a loophole in the definiton of "libre" hardware to allow it to qualify for the FSF's definiton of "Free" hardware. This renders the firmware unupdateable without shorting a connection. In the event a vulnerability is discovered in the modems or radios, the firmware cannot be updated without physically dismantling the phone. Firmware initialization is also no longer under the control of the host operating system because the initialization is carried out from outside the OS: changing or updating software on the host will not address these design defects. Although the modems and radios are not attached to the host via DMA, they rely on USB for isolation, which simply shifts the trust from the kernel driver to the kernel USB stack, and USB was never designed with distrusting the device plugged into it in mind unlike SMMU/IOMMU, which is specifically designed to mitigate unconstrained DMA. Current releases of the Librem 5 have been plagued by thermal throttling issues and poor battery life which in some cases has clocked in at less than 1 hour at idle. The Librem 5 does not even support software encryption and no progress has been made toward adding even LUKS encryption. The Librem 5 lacks a secure element for any hardware binding on the encryption and so would be entirely dependent on software-only encryption. The rebranded version of Debian that the Librem 5 uses as an operating system uses the same security model as the desktop stack, which is a perimeter or "all or nothing" security model. In the future, applications may be installed utilizing FlatPak. The threat model and measures FlatPak takes to meet it are as of yet unclear and uncertain. From https://github.com/Peter-Easton/GrapheneOS-Knowledge/blob/master/GrapheneOS-vs-Others.md https://github.com/Peter-Easton/GrapheneOS-Knowledge/blob/ma... which may be mildly out of date — but I doubt it. tl;dr Wake me up when you have an IOMMU!
- qchris 6y ago
  Thanks for the info, I hadn't heard about the USB isolation architecture issue. I'm not sure about the status of LUKS on PureOS, but I know that Mobian supports it and there is a supported build of Mobian for the Librem 5. First-hand, I've encrypted my Pinephone image, but don't have a Librem 5 so can't independently confirm that it actually includes that during the eMMC flashing process, although I don't have a reason to believe elsewise. Not sure if it's bad practice to share, but then what options do you use? If Debian's security model isn't enough, do you roll your own Linux base from something else instead? What kind of hardware is there as an alternative?
  - kop316 6y ago
    Considering most of his other post is factually incorrect and/or out of date, I am skeptical of the claim to be frank.
    - atat7024 6y ago
      "You're wrong!" I can play that game, too!
      - kop316 6y ago
        Skeptical != wrong https://www.merriam-webster.com/dictionary/skepticism https://www.merriam-webster.com/dictionary/skepticism https://www.merriam-webster.com/dictionary/wrong https://www.merriam-webster.com/dictionary/wrong If there are factual in accuracies with my claims, I am happy to be proven wrong. That's how I learn! I just need proper citations.
    - fsflover 6y ago
      Are you skeptical about bad security of USB? Here you go: https://www.qubes-os.org/doc/device-handling-security/#usb-security https://www.qubes-os.org/doc/device-handling-security/#usb-s....
      - 6y ago

by qchris 6y ago

seba_dos1 6y ago

You can even set up a secure boot chain with your own encryption keys, see: https://boundarydevices.com/high-assurance-boot-hab-i-mx8m-edition/ https://boundarydevices.com/high-assurance-boot-hab-i-mx8m-e... (it's a tutorial for a board that uses SoC from the same family as the Librem 5)

atat7024 6y ago

The Librem 5 is not as open or libre as its marketing has tried to insinuate, simply having its binary blob signed and validated firmware saved in write-protected read-only memory and loaded by a secondary coprocessor to exploit a loophole in the definiton of "libre" hardware to allow it to qualify for the FSF's definiton of "Free" hardware. This renders the firmware unupdateable without shorting a connection. In the event a vulnerability is discovered in the modems or radios, the firmware cannot be updated without physically dismantling the phone. Firmware initialization is also no longer under the control of the host operating system because the initialization is carried out from outside the OS: changing or updating software on the host will not address these design defects. Although the modems and radios are not attached to the host via DMA, they rely on USB for isolation, which simply shifts the trust from the kernel driver to the kernel USB stack, and USB was never designed with distrusting the device plugged into it in mind unlike SMMU/IOMMU, which is specifically designed to mitigate unconstrained DMA. Current releases of the Librem 5 have been plagued by thermal throttling issues and poor battery life which in some cases has clocked in at less than 1 hour at idle. The Librem 5 does not even support software encryption and no progress has been made toward adding even LUKS encryption. The Librem 5 lacks a secure element for any hardware binding on the encryption and so would be entirely dependent on software-only encryption. The rebranded version of Debian that the Librem 5 uses as an operating system uses the same security model as the desktop stack, which is a perimeter or "all or nothing" security model. In the future, applications may be installed utilizing FlatPak. The threat model and measures FlatPak takes to meet it are as of yet unclear and uncertain. From https://github.com/Peter-Easton/GrapheneOS-Knowledge/blob/master/GrapheneOS-vs-Others.md https://github.com/Peter-Easton/GrapheneOS-Knowledge/blob/ma... which may be mildly out of date — but I doubt it. tl;dr Wake me up when you have an IOMMU!

qchris 6y ago
Thanks for the info, I hadn't heard about the USB isolation architecture issue. I'm not sure about the status of LUKS on PureOS, but I know that Mobian supports it and there is a supported build of Mobian for the Librem 5. First-hand, I've encrypted my Pinephone image, but don't have a Librem 5 so can't independently confirm that it actually includes that during the eMMC flashing process, although I don't have a reason to believe elsewise. Not sure if it's bad practice to share, but then what options do you use? If Debian's security model isn't enough, do you roll your own Linux base from something else instead? What kind of hardware is there as an alternative?
- kop316 6y ago
  Considering most of his other post is factually incorrect and/or out of date, I am skeptical of the claim to be frank.
  - atat7024 6y ago
    "You're wrong!" I can play that game, too!
    - kop316 6y ago
      Skeptical != wrong https://www.merriam-webster.com/dictionary/skepticism https://www.merriam-webster.com/dictionary/skepticism https://www.merriam-webster.com/dictionary/wrong https://www.merriam-webster.com/dictionary/wrong If there are factual in accuracies with my claims, I am happy to be proven wrong. That's how I learn! I just need proper citations.
  - fsflover 6y ago
    Are you skeptical about bad security of USB? Here you go: https://www.qubes-os.org/doc/device-handling-security/#usb-security https://www.qubes-os.org/doc/device-handling-security/#usb-s....
    - 6y ago