Content protection device and content protection method

A content protection device configured to protect encrypted content in a memory card:

• wherein the memory card comprises:
• a non-volatile memory comprising a user data area, a protected area, a management area, and a system area,
• wherein the user data area is configured to store:
• an encrypted content obtained by encrypting a content with a content key,
• a content management file comprising content information associating a content with a content identifier,
• a content identifier and content key management file comprising information associating the content identifier with content key information indicative of the content key used for encrypting the content associated with the content identifier,
• a content key management file comprising data areas configured to store content key data comprising an encrypted content key obtained by encrypting the content key with a user key, and
• a user key location information management file comprising user key location information comprising information indicative of a user key management file comprising the user key, and information indicative of a location of the user key in the user key management file,
• wherein the user data area is configured to store content key location information and content keys link information,
• the content key location information being indicative of the content key management file comprising the content key data comprising the encrypted content key addressed by the content key information in the content identifier and content key management file and information indicative of location of the content key data in the content key management file, and
• the content keys link information associating user key location pointer in the user key location information, the user key location pointer addressing a location in the user key location information management file corresponding to a user key used for encrypting a content key located by the content key information and configured to store a content key management information file,
• wherein the protected area comprises the user key management file comprising a user key and hash values of data in the data areas,
• wherein the management area is configured to store a file management information of files in the user data area by sector, the file management information configured to store protection information for each sector,
• wherein the system area is configured to store authentication information;
• and
• an authentication module configured to authenticate with information from a host and the stored authentication information when the host issues a reading command indicative of reading a sector and the file management information comprising protection information corresponding to the sector, and to permit the reading when an authentication with the information from the host and the authentication information is successful,
• wherein the content protection device comprises a writer configured to write the protection information into the file management information in order to protect a content with protection, wherein the writer is configured to write the protection information corresponding to sectors configured to store the content key management information file comprising the content key link information comprising the content key position information of the encrypted content key corresponding to the content with protection, or to write the protection information corresponding to at least a portion of sectors comprising the content key management file comprising the encrypted content key corresponding to the content with protection.