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Firmware Verification with On-Chain Proofs

2025-01-056 minSentinel Team

Why Firmware Integrity Matters

A compromised firmware update is the most dangerous attack vector in robotics. If an attacker can modify the code running on your robots, they control everything — movement, sensors, communications, and data.

The Verification Pipeline

Sentinel's firmware verification works in 6 steps:

  1. Build — Firmware compiled from source
  2. Hash — SHA-256 and Blake3 hashes computed
  3. Sign — Hash signed with project key
  4. Anchor — Proof stored on Solana (immutable)
  5. Distribute — Firmware deployed to fleet
  6. Verify — Each robot verifies hash at boot

On-Chain Proofs

We use Solana's Memo program to store firmware proofs:

Transaction: 5Kj8...9xYz
Memo: SENTINEL:FIRMWARE:unit-0042:v2.4.1:SHA-256:a4e8f...91cd
Slot: 258491032

This creates an immutable, timestamped record that:

  • Cannot be modified after the fact
  • Can be independently verified by anyone
  • Proves the firmware existed at a specific point in time
  • Costs fractions of a cent per proof

Zero-Trust Boot

Every time a robot boots, it:

  1. Computes its own firmware hash
  2. Fetches the expected hash from Sentinel
  3. Verifies the on-chain proof matches
  4. Only proceeds if verification passes

If verification fails, the robot enters a quarantine state and alerts the fleet operator.