Patent ID: 11972031
Assignee: KONINKLIJKE PHILIPS N.V.
Field: Computer technology (Electrical engineering)
Classification: CPC G | IPC G

Claim 15:
16. A cryptographic method comprising:
executing a first software in a normal mode of a processor circuit,
wherein the processor circuit has the normal mode and a secure mode,
wherein a data and a code are isolated from the normal mode when the processor circuit is in the secure mode,
wherein the data comprises at least a first private key and a secret,
wherein the secret is shared with a user,
wherein executing the first software in a normal mode comprises: receiving an encrypted message and an encrypted authentication tag from the server, wherein the encrypted message and encrypted authentication tag are encrypted with a first public key, wherein the first public key corresponds to the first private key,
forwarding the encrypted message and encrypted authentication tag to second software, and

executing second software in the secure mode, wherein executing the second software in the secure mode comprises: decrypting the encrypted message and encrypted authentication tag with the first private key, wherein the first private key is stored in data of the secure mode,
displaying the shared secret, the message and the decrypted authentication tag so as to indicate to the user that the message is displayed by software running in the secure mode,
wherein a legacy software is arranged to receive the decrypted authentication tag from the user through an input interface.