SeedHammer v0.11.1: Constant Time Engraving

SeedHammer is a metal engraving machine for bitcoin used for creating robust singlesig/multisig with mnemonic seed, descriptor and QRs. It is air gapped, open source, verifiable and trustless.

SeedHammer v0.11.1: Constant Time Engraving
  • This update concerns SeedHammer source code, which is used to run the controller program for the SeedHammer engraving machine. It runs on the same hardware as the SeedSigner - Raspberry Pi Zero or Zero W, a WaveShare 1.3 inch 240x240 LCD hat and a Pi Zero compatible camera with a OV5647 sensor.
  • "This release contains an important security feature, improved camera scanning, easier building on macOS."
  • "Upgrading is strongly encouraged for the improved security."

What's new

  • "Before this release nearby attackers could deduce a seed phrase from the sound of the engraving needle during engraving. With this release all seed phrases will be engraved with identical sound profiles."
  • "SeedQRs are also being engraved with identical sound profiles but notice only the seed words and QR codes are engraved in this manner."
  • "The sound profile still leaks the length of your seed, the master fingerprint and the output descriptor."
  • "Improved camera scanning; small QRs scan better, scanning QR codes off a bright screen in a dark environment works better, and finally inverted QRs scan (bright QR on dark background - the plate to the right).

GitHub Repo