Access control for a memory device

1. A portable memory device comprising:

a storage medium comprising a private memory area; and

circuitry in communication with the storage medium, wherein the circuitry is operative to:

receive, from a host device in communication with the portable memory device, a password entered by a user to unlock the host device;

compare the password received from the host device with a password stored in the portable memory device; and

if the password received from the host device matches the password stored in the portable memory device, allow the host device to access the private memory area, wherein the password to unlock the host device also provides access to the private memory area.

2. The portable memory device of claim 1 , wherein the storage medium further comprises a public area storing computer-readable program code that, when executed on the host device:

locks user access to the host device after the portable memory device is placed in communication with the host device;

requests the password to unlock the host device; and

sends the password to the portable memory device.

3. The portable memory device of claim 1 , wherein the storage medium further comprises an area not accessible to the host device, and wherein the password stored in the portable memory device is stored in that area.

4. The portable memory device of claim 1 , wherein the circuitry is further operative to perform encryption on data to be stored in the private memory area and decryption of encrypted data to be read from the private memory area.

5. The portable memory device of claim 1 , wherein the password to unlock the host device is generated by a user of the host device.

6. The portable memory device of claim 1 , wherein the storage medium further comprises a public area, and wherein the circuitry is further operative to allow access to the public area without requiring a password.

7. The portable memory device of claim 1 , wherein the portable memory device comprises a memory card.

8. The portable memory device of claim 1 , wherein the host device comprises a mobile phone.

9. A portable memory device comprising:

a storage medium comprising:

a private memory area; and

a public area storing computer-readable program code that, when executed on a host device in communication with the portable memory device:

locks user access to the host device after the portable memory device is placed in communication with the host device;

requests a password from a user to unlock the host device; and

sends the password to the portable memory device; and

circuitry in communication with the storage medium, wherein the circuitry is operative to allow the host device to access the private memory area if the password matches a password stored in the portable memory device, wherein the password to unlock the host device also provides access to the private memory area.

10. The portable memory device of claim 9 , wherein the portable memory device is manufactured with a default password, and wherein the circuitry is further operative to replace the default password with the password received from the host device.

11. The portable memory device of claim 9 , wherein the public area stores additional computer-readable program code that, when executed on the host device:

determines if a password has been established to unlock the host device; and

if a password has not been established to unlock the host device, establishes a password to unlock the host device.

12. The portable memory device of claim 9 , wherein the public area stores additional computer-readable program code that, when executed on the host device:

determines whether the password stored in the portable memory device was established by the host device or by a different host device;

requests a password from the user to unlock the different host device if the password stored in the portable memory device was established by the different host device; and

sends the password to unlock the different host device to the portable memory device;

wherein the circuitry is further operative to allow the host device to access the private memory area if the password to unlock the different host device matches the password stored in the portable memory device.

13. The portable memory device of claim 12 , wherein the circuitry is further operative to replace the password stored in the portable memory device with the password to unlock the host device.

14. The portable memory device of claim 12 , wherein the portable memory device stores a unique ID of a host device that established the password stored in the portable memory device, and wherein the additional computer-readable program code determines whether the password stored in the portable memory device was established by the host device or by the different host device by comparing the stored unique ID with the unique ID of the host device.

15. The portable memory device of claim 9 , wherein the public area stores additional computer-readable program code that, when executed on a different host device, requests the password to unlock the host device.

16. The portable memory device of claim 15 , wherein the different host device comprises a personal computer.

17. The portable memory device of claim 9 , wherein the storage medium further comprises an area not accessible to the host device, and wherein the password stored in the portable memory device is stored in that area.

18. The portable memory device of claim 9 , wherein the circuitry is further operative to perform encryption on data to be stored in the private memory area and decryption of encrypted data to be read from the private memory area.

19. The portable memory device of claim 9 , wherein the password to unlock the host device is generated by a user of the host device.

20. The portable memory device of claim 9 , wherein the circuitry is further operative to allow access to the public area without requiring a password.

21. The portable memory device of claim 9 , wherein the portable memory device comprises a memory card.

22. The portable memory device of claim 9 , wherein the host device comprises a mobile phone.

23. A method for providing access control for a portable memory device comprising a storage medium comprising a private memory area, the method comprising:

receiving, from a host device in communication with a portable memory device, a password entered by a user to unlock the host device;

comparing the password received from the host device with a password stored in the portable memory device; and

if the password received from the host device matches the password stored in the portable memory device, allowing the host device to access a private memory area in a storage medium in the memory device, wherein the password to unlock the host device also provides access to the private memory area.

24. The method of claim 23 , wherein the storage medium further comprises a public area storing computer-readable program code that, when executed on the host device:

locks user access to the host device after the portable memory device is placed in communication with the host device;

requests the password to unlock the host device; and

sends the password to the portable memory device.

25. The method of claim 23 , wherein the storage medium further comprises an area not accessible to the host device, and wherein the password stored in the portable memory device is stored in that area.

26. The method of claim 23 further comprising performing at least one of the following;

encrypting on data to be stored in the private memory area; and

decrypting encrypted data to be read from the private memory area.

27. The method of claim 23 , wherein the password to unlock the host device is generated by a user of the host device.

28. The method of claim 23 , wherein the storage medium further comprises a public area, and wherein the method further comprises allowing access to the public area without requiring a password.

29. The method of claim 23 , wherein the portable memory device comprises a memory card.

30. The method of claim 23 , wherein the host device comprises a mobile phone.

31. A method for providing access control for a portable memory device comprising a storage medium comprising a private memory area, the method comprising:

providing a host device in communication with a portable memory device with computer-readable program code stored in a public area of a storage medium of the portable memory device, wherein the computer-readable program code, when executed on the host device, locks user access to the host device after the portable memory device is placed in communication with the host device and requests a password from a user to unlock the host device;

receiving the password from the host device; and

allowing the host device to access a private memory area of the storage medium of the portable memory device if the password matches a password stored in the portable memory device, wherein the password to unlock the host device also provides access to the private memory area.

32. The method of claim 31 , wherein the portable memory device is manufactured with a default password, and wherein the method further comprises replacing the default password with the password received from the host device.

33. The method of claim 31 further comprising providing the host device with additional computer-readable program code that, when executed on the host device:

determines if a password has been established to unlock the host device; and

if a password has not been established to unlock the host device, establishes a password to unlock the host device.

34. The method of claim 31 further comprising providing the host device with additional computer-readable program code that, when executed on the host device:

determines whether the password stored in the portable memory device was established by the host device or by a different host device;

requests a password from the user to unlock the different host device if the password stored in the portable memory device was established by the different host device; and

sends the password to unlock the different host device to the portable memory device.

35. The method of claim 34 further comprising replacing the password stored in the portable memory device with the password to unlock the host device.

36. The method of claim 34 , wherein the portable memory device stores a unique ID of a host device that established the password stored in the portable memory device, and wherein the additional computer-readable program code determines whether the password stored in the portable memory device was established by the host device or by the different host device by comparing the stored unique ID with the unique ID of the host device.

37. The method of claim 31 further comprising providing a different host device with computer-readable program code that, when executed on the different host device, requests the password to unlock the host device.

38. The method of claim 37 , wherein the different host device comprises a personal computer.

39. The method of claim 31 , wherein the storage medium further comprises an area not accessible to the host device, and wherein the password stored in the portable memory device is stored in that area.

40. The method of claim 31 further comprising performing at least one of the following;

encrypting on data to be stored in the private memory area; and

decrypting encrypted data to be read from the private memory area.

41. The method of claim 31 , wherein the password to unlock the host device is generated by a user of the host device.

42. The method of claim 31 further comprising allowing access to the public area without requiring a password.

43. The method of claim 31 , wherein the portable memory device comprises a memory card.

44. The method of claim 31 , wherein the host device comprises a mobile phone.