Implementation of an integrity-protected secure storage

• US 20060259790A1
• Filed: 05/13/2005
• Published: 11/16/2006
• Est. Priority Date: 05/13/2005
• Status: Active Grant

• Current Assignee: Nokia Technologies Oy (Nokia Corporation)
• Original Assignee: Nokia Corporation
• Inventors: Asokan, Nadarajah, Paatero, Lauri, Ekberg, Jan-Erik
• Granted Patent: US 9,171,187 B2
• Time in Patent Office: Days
• US Class Current: 713/194
• CPC Class Codes: G06F 21/606 by securing the transmission between two devices or processes
• CPC Class Codes: G06F 21/62 Protecting access to data via a platform, e.g. using keys or access control rules
• CPC Class Codes: G06F 21/71 to assure secure computing or processing of information
• CPC Class Codes: G06F 21/78 to assure secure storage of data address-based protection against unauthorised use of memory G06F12/14; record carriers for use with machines and with at least a part designed to carry digital markings G06K19/00
• CPC Class Codes: G06F 21/79 in semiconductor storage media, e.g. directly-addressable memories
• CPC Class Codes: G06Q 20/341 Active cards, i.e. cards including their own processing means, e.g. including an IC or chip
• CPC Class Codes: G06Q 20/3576 Multiple memory zones on card
• CPC Class Codes: G06Q 20/40975 using encryption therefor
• CPC Class Codes: G07F 7/1008 Active credit-cards provided with means to personalise their use, e.g. with PIN-introduction/comparison system
• CPC Class Codes: H04L 2209/12 Details relating to cryptographic hardware or logic circuitry
• CPC Class Codes: H04L 2209/603 Digital right managament [DRM]
• CPC Class Codes: H04L 2209/80 Wireless network architectures or network communication protocols for wireless network security H04W12/00
• CPC Class Codes: H04L 9/0833 involving conference or group key network architectures or network communication protocols for key management in group communication in a packet data network H04L63/065
• CPC Class Codes: H04L 9/0838 Key agreement, i.e. key establishment technique in which a shared key is derived by parties as a function of information contributed by, or associated with, each of these network architectures or network communication protocols for key exchange in a packet data network H04L63/061
• CPC Class Codes: H04L 9/0891 Revocation or update of secret information, e.g. encryption key update or rekeying

Abstract

An internal but not integrated security token is provided for a device which includes a first integrated circuitry including a secure processor. The security token is provided by a second integrated circuitry separate from the first circuitry. The second integrated circuitry includes a secure non-volatile storage. The secure processor communicates information to the second circuitry in a secure manner for the secure information to be securely stored in the secure non-volatile storage, and the second integrated circuitry communicates information stored in its secure non-volatile storage to the secure processor in a secure manner. Communications is secured by means of cryptography. The first integrated circuitry and the second integrated circuitry are internal parts of the device. An initialization method for distributing a secure key to be shared between the circuitries and to be used in cryptography is also disclosed.

Claims

1. A device which comprises:

a first integrated circuitry for forming a first trust zone, the first integrated circuitry comprising a secure processor; and

a second integrated circuitry separate from the first circuitry for forming a second trust zone, the second integrated circuitry comprising a secure non-volatile storage within the second trust zone, wherein

the secure processor is configured to communicate information from the first trust zone to the second trust zone in a secure manner for the secure information to be securely stored in the secure non-volatile storage;

the second integrated circuitry is configured to communicate information stored in its secure non-volatile storage from the second trust zone to the secure processor within the first trust zone in a secure manner; and

wherein

said first integrated circuitry and said second integrated circuitry are internal parts of the device.

2. The device of claim 1, wherein the first and second integrated circuitries are adapted to securely initialise a unique secure key to be shared between the first and second trust zones.

3. The device of claim 2, wherein the first integrated circuitry is adapted to share a key with a secure key-distribution server and the second integrated circuitry is adapted to share another key with the secure key-distribution server in order to secure delivery of said unique secure from the secure key-distribution server to the first and second integrated circuits.

4. The device of claim 1, wherein the first and second circuitries are adapted to establish a secure communication protocol to be used between the first and second trust zones.

5. The device of claim 4, wherein the secure communication protocol comprises cryptographic algorithms to be performed by using said unique secure key in order to secure communications between the first and second trust zones.

6. The device of claim 4, wherein the protocol contains at least READ and WRITE commands and key-change operations.

7. The device of claim 1, wherein the device is provided with key-state management enabling more than one key to be shared between the first and second trust zones.

8. The device of claim 7, wherein the non-volatile storage of the second trust zone comprises at least one maintained key-state variable indicating the shared key to be used in communication.

9. The device of claim 7, wherein the second integrated circuit is adapted to choose a correct key-state by reading a current value of the key-state variable upon power-on operation.

10. The device of claim 6, wherein the secure processor is adapted to include a random value as a parameter in a READ command so that it can verify that a subsequent result received from the second integrated circuitry is fresh (not replayed).

11. The device of claim 6, wherein the second integrated circuitry is adapted to check whether an old value of a target memory cell of its secure non-volatile storage is contained as a parameter in a received WRITE command, and to permit a write operation only if this is the case.

12. The device of claim 1, wherein the second integrated circuitry is configured to encrypt parameters of a response to a received command by using the unique secure key, and by including an externally unpredictable component in the parameters so that even a same command will result in different responses.

13. The device of claim 12, wherein the unpredictable component is a value derived from a linear feedback shift register driven by a clock

14. The method of claim 1, wherein the second integrated circuitry is adapted to use only a single cryptographic primitive for all of its cryptographic operation.

15. The device of claim 1, wherein the first integrated circuitry is digital and the second integrated circuitry is analog.

16. The device of claim 1, wherein said second circuitry resides on an energy management chip of a mobile phone.

17. The device of claim 1, wherein the first circuitry and the second circuitry form part of an assembly module.

18. The device of claim 1, wherein said secure information comprises information indicating a state of the device.

19. The device of claim 1, wherein the device comprises a second non-volatile memory for storing the secure information and encrypting it by using a key.

20. The device of claim 19, wherein the device is arranged to compare contents of the second non-volatile memory with contents of the secure non-volatile storage of the second trust zone.

21. The device of claim 1, wherein the device is a hand-held communication device, such as a mobile phone.

22. A method for initializing a secure key to be shared between a first integrated circuitry and a second integrated circuitry, the method comprising:

distributing the secure key to be shared between the first integrated circuitry and the second integrated circuitry from a secure key-distribution server to the first and second integrated circuitry, wherein the method comprises;

protecting the distribution of the secure key from the secure key-distribution server to the first integrated circuitry using a first key, the first key being a key shared beforehand between the first integrated circuitry and the secure key-distribution server; and

protecting the distribution of the secure key from the secure key-distribution server to the second integrated circuitry using a second key, the second key being a key shared beforehand between the second integrated circuitry and the secure key-distribution server.

23. An integrated circuitry, which comprises:

a secure processor for issuing and encrypting commands to be transferred to another integrated circuitry in accordance with a secure protocol, wherein

the secure protocol comprises a key-change operation by which a secure key shared between the integrated circuitry and said another integrated circuitry can be changed.

24. A computer program executable by a secure processor of an integrated circuitry, comprising:

program code for issuing commands to be transferred to another integrated circuitry in accordance with a secure protocol; and

program code for causing the secure processor to initiate a key-change operation by which a secure key shared between the integrated circuitry and said another integrated circuitry is changed.

25. An integrated circuitry, which comprises:

a non-volatile memory for storing secure data received from another integrated circuitry; and

logics for accessing said non-volatile memory, wherein the integrated circuitry is adapted to communicate secure data stored on said non-volatile memory and secured by means of cryptography to said another integrated circuitry, and wherein

the integrated circuitry is configured to use a single cryptographic primitive.

26. A computer program executable in an integrated circuitry, comprising:

program code for securing communications with another integrated circuitry by using a key shared between the integrated circuitry and said another integrated circuitry; and

program code for changing between different key-states of different security levels.

27. An energy management chip adapted to carry out energy management of a device, the energy management chip comprising a secure non-volatile memory and logics so as to provide a security token for a secure processor external to said energy management chip.