Apparatus and method for encrypting security key in mobile communication terminal

• US 20080019521A1
• Filed: 05/03/2007
• Published: 01/24/2008
• Est. Priority Date: 05/30/2006
• Status: Active Grant

• Current Assignee: Samsung Electronics Co. Ltd.
• Original Assignee: Samsung Electronics Co. Ltd.
• Inventors: Ahn, Chi-Hun
• Granted Patent: US 8,223,971 B2
• Time in Patent Office: Days
• US Class Current: 380/247
• CPC Class Codes: H04L 2209/80 Wireless network architectures or network communication protocols for wireless network security H04W12/00
• CPC Class Codes: H04L 2463/062 applying encryption of the keys cryptographic mechanisms or cryptographic arrangements for key distribution using key encryption key H04L9/0822
• CPC Class Codes: H04L 63/06 for supporting key management in a packet data network cryptographic mechanisms or cryptographic arrangements for key management H04L9/08
• CPC Class Codes: H04L 63/0853 using an additional device, e.g. smartcard, SIM or a different communication terminal cryptographic mechanisms or cryptographic arrangements for entity authentication involving additional secure or trusted devices H04L9/3234
• CPC Class Codes: H04L 9/0894 Escrow, recovery or storing of secret information, e.g. secret key escrow or cryptographic key storage
• CPC Class Codes: H04W 12/041 Key generation or derivation

Abstract

Provided is an apparatus and method for storing a security key in a mobile communication terminal. In the method, the security key is generated randomly. The generated security key is encrypted in a predetermined encryption scheme. The encrypted security key is stored in the mobile communication terminal. Therefore, even if the stored security keys are read by hacking or memory dump, it is impossible to detect the accurate security keys.

Claims

1. A method for storing a security key in a mobile communication terminal, comprising the steps of:

generating the security key randomly;

encrypting the generated security key; and

storing the encrypted security key.

2. The method of claim 1, wherein the encrypting step uses Walsh code spreading.

3. The method of claim 1, wherein the step of encrypting the generated security key comprises:

converting the generated security key into a bit-format; and

spreading the bit-format security key by a Walsh code to generate random data.

4. An apparatus for storing a security key in a mobile communication terminal, comprising:

a controller for generating the security key randomly and encrypting the generated security key; and

a memory unit for storing the encrypted security key.

5. The apparatus of claim 4, wherein the controller comprises:

a security key generator for generating the security key randomly; and

an encryptor for encrypting the generated security key.

6. The apparatus of claim 5, wherein an encryptor uses Walsh code spreading.

7. The apparatus of claim 4, wherein the encrypted security key is stored in a nonvolatile area of the memory unit.

8. A method for storing a control key for disabling personalization in a mobile communication terminal with a Subscriber Identity Module (SIM) card, comprising the steps of:

generating the control key randomly;

encrypting the generated control key; and

storing the encrypted control key.

9. The method of claim 8, wherein the encrypting step uses Walsh code spreading.

10. The method of claim 8, wherein the step of encrypting the generated control key comprises:

converting the generated control key into a bit-format; and

spreading the bit-format control key by a Walsh code to generate random data.

11. A method for disabling personalization in a mobile communication terminal with a Subscriber Identity Module (SIM) card, comprising the steps of:

detecting an encrypted control key that is stored and a character string for Walsh covering;

decrypting the encrypted control key using a Walsh code index contained in the character string;

comparing the decrypted control key with a control key contained in the character string; and

depersonalizing the personalization if the decrypted control key is identical to the control key contained in the character string.

12. A mobile communication terminal for storing a security key comprising:

means for generating the security key randomly;

means for encrypting the generated security key; and

means for storing the encrypted security key.

13. The mobile communication terminal of claim 12, wherein the encrypting step uses Walsh code spreading.

14. The mobile communication terminal of claim 12, wherein means for encrypting the generated security key comprises:

means for converting the generated security key into a bit-format; and

means for spreading the bit-format security key by a Walsh code to generate random data.

15. A mobile communication terminal with a Subscriber Identity Module (SIM) card for disabling personalization comprising:

means for identifying an encrypted control key that is stored and a character string for Walsh covering;

means for decrypting the encrypted control key using a Walsh code index contained in the character string; and

means for comparing the decrypted control key with a control key contained in the character string.

16. The mobile communication terminal of claim 15, further comprising means for depersonalizing the personalization if the decrypted control key is identical to the control key contained in the character string.

17. The mobile communication terminal of claim 15, further comprising means for maintaining the personalization if the decrypted control key is not identical to the control key contained in the character string.