Smart Device Firmware Update: Chain of Trust

Every secure smart-home device — a hub, a smart lock, a router — has to answer one question before it installs new firmware: did this really come from the manufacturer, unmodified? This simulator renders the vendor's signing server, the network in between, and the device's verification gate in 3D, and pushes a firmware package through a real (simplified) RSA-style signature check: s^e mod n compared against the firmware's hash. Choose between a legitimate update, a tampered payload, a forged signature, or a rollback attack that replays an old, already-patched firmware version, and watch the package pass or get quarantined at the gate. An anti-rollback toggle demonstrates why signature verification alone is not enough — a validly-signed old firmware image still needs a monotonic version floor to stop downgrade attacks.