Storage card with integral file system, access control and cryptographic support

• US 20030173400A1
• Filed: 03/18/2002
• Published: 09/18/2003
• Est. Priority Date: 03/18/2002
• Status: Active Grant

• Current Assignee: Renesas Electronics America Inc.(f/k/a Integrated Device Technology, Inc) (Renesas Electronics Corporation)
• Original Assignee: Hitachi Semiconductor America, Inc. (Renesas Electronics Corporation)
• Inventors: Kawasaki, Shumpei, Morita, Toshiyasu
• Granted Patent: US 6,845,908 B2
• Time in Patent Office: Days
• US Class Current: 235/380
• 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

Abstract

A storage card includes non-volatile memory; an authentication engine capable to authenticate a password and transmit authorization to read from and write to files; a file system, coupled to the authentication engine, capable to receive file commands from a computer, receive authorization from the authentication engine, and to transmit file instructions; and a sector driver, coupled to the file system and the memory, capable to read from and write to the memory in response to the instructions received from the file system.

Claims

1. A portable memory device that can be removably coupled to a computer, comprising:

non-volatile memory;

an authorization engine capable to authenticate a password and transmit authorization to read from the memory;

a file system, coupled to the authentication engine, capable to receive file read request from the computer, receive authorization from the authentication engine, and transmit file read request.

2. The device of claim 1, further comprising an encryption engine, coupled to the file system, capable to encrypt files before storage in the memory and to decrypt files stored in the memory.

3. The device of claim 2, wherein the encryption engine uses at least one symmetric encryption and asymmetric encryption.

4. The device of claim 1, wherein the authentication engine is further capable to transmit authorization to write to the memory and wherein the file system is further capable to receive file write requests from the computer and transmit file write instructions, the device further comprising:

a sector driver, coupled to the file system and the memory, capable to write to the memory in response to the instructions received from the file system.

5. The device of claim 1, wherein the authentication engine receives a password from the computer.

6. The device of claim 5, further comprising a biometric reader integral with the device and coupled to the authentication engine, and wherein the password includes biometric data received from the biometric reader.

7. The device of claim 6, wherein the biometric reader includes a fingerprint scanner.

8. The device of claim 1, further comprising a single input/output interface for temporarily communicatively coupling the device to the computer and wherein the authentication engine and file system both communicate with the computer via the single interface.

9. The device of claim 1, wherein the device is tamper proofed.

10. A method implemented in a portable memory device, comprising:

receiving a file-oriented write request from a computer, the write request including data;

receiving a password;

authenticating the password;

encrypting the data if the password is authenticated; and

writing the encrypted data and a decryption key to memory within the device if the password is authenticated.

11. The method of claim 10, wherein the encrypting uses a symmetric encryption algorithm.

12. The method of claim 10, wherein the encrypting uses an asymmetric encryption algorithm.

13. The method of claim 10, wherein the password is received from a computer.

14. The method of claim 10, wherein the password includes biometric data from a biometric reader that is integral with the portable memory device.

15. The method of claim 14, wherein the biometric data includes a fingerprint.

16. A method implemented in a portable memory device, comprising:

receiving a file-oriented read request from a computer;

receiving a password; and

authenticating the password;

decrypting a file associated with the read request that is stored in memory of the device if the password is authenticated; and

transmitting the decrypted file to the computer if the password is authenticated.

17. The method of claim 16, wherein the password is received from a computer.

18. The method of claim 16, wherein the password includes biometric data from a biometric reader that is integral with the portable memory device.

19. The method of claim 18, wherein the biometric data includes a fingerprint.

20. A removable memory apparatus for a computer, comprising:

a file name analyzer capable to receive a file name from the computer and get location information corresponding to the file name from a directory area in the memory; and

a sector driver, coupled to the file name analyzer, capable to receive the location information from the file name analyzer and get data corresponding to the file name in the memory.

21. The apparatus of claim 20, further comprising an encryption engine, coupled to the sector driver, capable to decrypt files in the memory.

22. The apparatus of claim 20, wherein the sector driver is further capable to write to memory.

23. The apparatus of claim 20, wherein the device is tamper proofed.

24. The apparatus of claim 20, further comprising an authentication engine, coupled to the file name analyzer, capable to receive and authenticate a password and wherein the sector driver is capable to get data only after password authentication.

25. A method implemented in a portable memory device, comprising:

receiving a file-oriented read request from a computer;

receiving a password;

authenticating the password; and

transmitting a file associated with the read request from memory within the device to the computer if the password is authenticated.

26. The method of claim 25, wherein the password is received from a computer.

27. The method of claim 25, wherein the password includes biometric data from a biometric reader that is integral with the portable memory device.

28. The method of claim 25, wherein the biometric data includes a fingerprint.

29. The method of claim 25, further comprising decrypting the file before transmitting the file if the password is authenticated.