betrusted-soc

It’s a good question - the analysis seems to ignore the need for non-free software to properly build the FPGA bitstream files from source. We have no way to know the Xilinx tools are safe. None of those papers address the tool chain question AFAIK. Additionally, it is difficult to know if a user has downloaded the real Xilinx software tool chain; the git repo ( https://github.com/betrusted-io/betrusted-soc ) from has no verification step for step 7. There is a public key and a hash, they could include this in the repo and at least it would make a targeted attack a little more difficult. Additionally they could use a git sub module for step 6 and have a better risc-v supply chain security story. It seems trivial to fix that detail, so I am sure it will be fixed if they’re alerted. These setup steps are trivial security issues, simple to f

The only thing that seems to be randomized in building precursor is the P&R seed. https://github.com/betrusted-io/betrusted-soc/blob/main/betr... That prevents attacks where you have a known place on the FPGA is naughty, but not when you have a lot of elements that are naughty on certain input. It doesn't even really protect against known-naughty-place: there's not infinite freedom on P&R with fixed I/O locations.

Thanks for the enthusiasm! I happen to be up really late tonight, but I'm going to bed soon. Thank you for the support and kind words. The accelerometer is the LSM6DS3, I'll refer you directly to the manufacturer's website: https://www.st.com/en/mems-and-sensors/lsm6ds3.html You can find out more about how it's integrated at https://github.com/betrusted-io/betrusted-hardware/blob/mast... (note: this is a "DVT" schematic, bugs were found, they are currently being fixed, but they aren't related to the accelerometer). The TL;DR is that the accelerometer is integrated so that it's in the "always on" untrusted domain, so to access it from the main FPGA "SoC" you have to go through the system controller FPGA ("EC" as we call it). The idea is for it to be available in power down states for anti-tamper, hence the extra layer of complication. Talk