PUF BASED SECURING OF DEVICE UPDATE

摘要

For securing an update of a device (100), the device (100) provides a physical unclonable function (PUF). The device (100) generates a device-specific key by the PUF and encrypts a secret key by calculating an invertible cryptographic function, e.g., an exclusive-or, XOR, combination, of the secret key and the device-specific key generated by the PUF. The device (100) stores encrypted secret key. When receiving an update, the device (100) reconstructs the secret key from the stored encrypted secret key, by utilizing the device-specific key generated by the PUF to invert the cryptographic function of the secret key and the device-specific key, and decrypts the update with the reconstructed secret key.