go-rpi-crypto

Pure Go library and CLI to access the Raspberry Pi's firmware cryptographic functions. The implementation was based on the utility rpifwcrypto. This CLI provides additional features such as signing JWTs and exporting public keys in JWKS or PEM format.

CLI

Usage:
  go-rpi-crypto [flags]
  go-rpi-crypto [command]

Available Commands:
  completion       Generate the autocompletion script for the specified shell
  get-key-status   Gets the status of a specified key
  get-num-otp-keys Gets the number of OTP keys
  help             Help about any command
  hmac             Calculates HMAC-SHA256 of an input file
  jwks             Exports the public key as a JWKS document
  jwt              Signs a JWT using an OTP ECDSA key
  pubkey           Retrieves the public key in DER, PEM, or hex format
  sign             Signs a file hash using an OTP key

Library

import (
  "fmt"
  "crypto/sha256"
  "github.com/ezoidc/go-rpi-crypto/api"
)

func main() {
  keyID := 1
  data := []byte("data to sign")
  hash := sha256.Sum256(data)
  sigBytes, err := api.ECDSASign(0, uint32(keyID), hash[:])
  if err != nil {
    println("Error signing data:", err)
    return
  }
  println("Signature:", fmt.Sprintf("%x", sigBytes))
}