Secure cryptoprocessor

1. A cryptoprocessor comprising:

physical unclonable function circuitry comprising at least one physical unclonable function, and

at least one processing core configured to:

issue a request for a challenge to a server;

receive the challenge from the server;

provide the challenge as input to the physical unclonable function circuitry to derive a response to the challenge;

use the response as a first encryption key to encrypt a second encryption key;

cause the encrypted second encryption key to be provided to a the server;

use the second encryption key to establish a secure end-to-end connection with a correspondent party distinct from the server, and

wherein the cryptoprocessor is configured to decrypt an encryption key of the correspondent party with a second response as a key to obtain the encryption key of the correspondent party, the second response obtained from the physical unclonable function circuitry using a second challenge as input.

2. The cryptoprocessor according to claim 1 , configured to apply a hash-based message authentication code to the second encryption key and at least one object identifier to process a request for object identification, and cause the resulting hash value to be provided as a response to the request for object identification.

3. The cryptoprocessor according to claim 2 , wherein the cryptoprocessor is configured to obtain the at least one object identifier from an apparatus the cryptoprocessor is installed in.

4. The cryptoprocessor according to claim 1 , configured to provide to the physical unclonable function circuitry an attestation challenge as input to derive an attestation response, to apply hash-based message authentication to the attestation response and an executable of an application, and to provide an output of the hash-based message authentication to the application as a certificate.

5. The cryptoprocessor according to claim 4 , further configured to request the attestation challenge from a server.

6. The cryptoprocessor according to claim 5 , further configured to receive a public key of the application from the application.

7. The cryptoprocessor according to claim 1 , wherein the cryptoprocessor does not comprise circuitry configured to perform asymmetric encryption operations.

8. The cryptoprocessor according to claim 1 , further comprising a shared secret, wherein the shared secret is established with the party which issued the challenge, the shared secret is formed with second encryption key, a part of the shared secret is formed with the second encryption key, or the shared secret is shared with the second encryption key.

9. A method in a cryptoprocessor, comprising:

issuing a request for a challenge to a server;

receiving the challenge from the server;

deriving a response to the challenge received by providing the challenge as input to physical unclonable function circuitry of the cryptoprocessor;

using the response as a first encryption key to encrypt a second encryption keys;

causing the encrypted second encryption key to be provided to the server;

using the second encryption key to establish a secure end-to-end connection with a correspondent party distinct from the server and; obtaining an encryption key of the correspondent party by decrypting the encryption key of the correspondent party using a second response as a key, the second response being obtained from the physical unclonable function circuitry using a second challenge as input.

10. The method according to claim 9 , further comprising processing a request for object identification by applying a hash-based message authentication code to the second encryption key and at least one object identifier, and by causing the resulting hash value to be provided as a response to the request for object identification.

11. The method according to claim 10 , further comprising obtaining the at least one object identifier from an apparatus the cryptoprocessor is installed in.

12. The method according to claim 9 , further comprising deriving an attestation response by providing to the physical unclonable function circuitry an attestation challenge as input, applying hash-based message authentication to the attestation response and an executable of an application, and providing an output of the hash-based message authentication to the application as a certificate.

13. The method according to claim 12 , further comprising requesting the attestation challenge from a server.

14. The method according to claim 12 , further comprising receiving a public key of the application from the application.

15. A non-transitory computer readable medium having stored thereon a set of computer readable instructions that, when executed by at least one processing core of a cryptoprocessor, cause the cryptoprocessor to at least:

issue a request for a challenge to a server;

receive the challenge from the server;

derive a response to a challenge received from outside the cryptoprocessor by providing the challenge as input to physical unclonable function circuitry of the cryptoprocessor;

use the response as a first encryption key to encrypt a second encryption key;

cause the encrypted second encryption key to be provided to the server;

use the second encryption key to establish a secure end-to-end connection with a correspondent party distinct from the server and;

obtain an encryption key of the correspondent party by decrypting the encryption key of the correspondent party using a second response as a key, the second response being obtained from the physical unclonable function circuitry using a second challenge as input.