Semiconductor memory card, data reading apparatus, and data reading/reproducing apparatus

A semiconductor memory card for use with an electronic device, said semiconductor memory card comprising:

• a rewritable nonvolatile memory;
• and
• a control unit operable to control accesses by the electronic device to an authentication area and a non-authentication area in said rewritable nonvolatile memory;
• said control unit comprising:
• an authentication unit operable to perform an authentication process to check whether the electronic device has authority to access said semiconductor memory card, and affirmatively authenticate the electronic device when the electronic device has authority to access said semiconductor memory card;
• and
• an authentication area access control unit operable to permit the electronic device to access the authentication area only when said authentication unit affirmatively authenticates the electronic device;
• wherein the authentication area and the non-authentication area are provided by dividing a continuous area of a predetermined size in said rewritable nonvolatile memory into two parts;
• said semiconductor memory card further comprising:
• a device operable to hold information relating to an area size of said rewritable nonvolatile memory;
• and
• an area resizing unit operable to resize the authentication area and the non-authentication area, wherein said area resizing unit resizes the authentication area and the non-authentication area based on the information relating to the area size of said rewritable nonvolatile memory when said authentication unit affirmatively authenticates the electronic device;
• wherein:
• said authentication unit is operable to generate a key reflecting a result of the authentication process;
• said authentication area access control unit is operable to decrypt an encrypted instruction sent from the electronic device using the key generated by said authentication unit, and is operable to control accesses by the electronic device to the authentication area in accordance with the decrypted instruction;
• and
• said authentication unit is operable to perform a challenge-response type mutual authentication with the electronic device, and generate the key from challenge data and response data, the challenge data being sent to the electronic device to check whether the electronic device has authority to access said semiconductor memory card, and the response data being generated to indicate that said authentication unit has authority to access said semiconductor memory card.

A semiconductor memory card for use with an electronic device, said semiconductor memory card comprising:

• a rewritable nonvolatile memory;
• and
• a control unit operable to control accesses by the electronic device to an authentication area and a non-authentication area in said rewritable nonvolatile memory;
• said control unit comprising:
• an authentication unit operable to perform an authentication process to check whether the electronic device has authority to access said semiconductor memory card, and affirmatively authenticate the electronic device when the electronic device has authority to access said semiconductor memory card;
• and
• an authentication area access control unit operable to permit the electronic device to access the authentication area only when said authentication unit affirmatively authenticates the electronic device;
• wherein the authentication area and the non-authentication area are provided by dividing a continuous area of a predetermined size in said rewritable nonvolatile memory into two parts;
• said semiconductor memory yard further comprising:
• a device operable to hold information relating to an area size of said rewritable nonvolatile memory;
• and
• an area resizing unit operable to resize the authentication area and the non-authentication area, wherein said area resizing unit resizes the authentication area and the non-authentication area based on the information relating to the area size of said rewritable nonvolatile memory when said authentication unit affirmatively authenticates the electronic device;
• wherein said authentication unit is operable to request a user of the electronic device to input a user key during the authentication process, the user key being information unique to the user, and wherein said control unit further comprises:
• a user key storage unit operable to store the user key;
• an identification information storage unit operable to store a piece of identification information identifying an electronic device that has been affirmatively authenticated by said authentication unit;
• and
• a user key request prohibition unit operable to obtain a piece of identification information from a target electronic device after said authentication unit starts the authentication process, check whether the piece of identification information obtained from the target electronic device has already been stored in said identification information storage unit, and prohibit said authentication unit from requesting a user of the electronic device to input a user key when the piece of identification information obtained from the target electronic device has already been stored in said identification information storage unit.