摘要:
An information recording device, which includes a nonvolatile memory whose areas are managed using an FAT file system and enhances the reliability of directory entries using a cyclic shift checksum, recalculates the cyclic shift checksum efficiently and performs seeking at a higher speed. A nonvolatile memory (25) of an information recording device 2 is managed using an FAT file system. In the memory, a plurality of directory entries are allocated to a single file. The device enhances the reliability of the directory entries using a cyclic shift checksum, and manages information indicating the position and the size of a storage area of file data using an extent information entry (203). The device further uses an update information entry (204) and a dummy entry (205).
摘要:
In a target apparatus which stores at least one piece of domain key information in a first area and a plurality of pieces of content key information each associated with any one of the domain key information in a second area, a method for generating data for detecting tampering of the content key information. The method comprises the steps of encrypting the content key information associated with one of the domain key information using a chain encryption technique, extracting data at predetermined positions in the encrypted content key information, concatenating the pieces of data extracted at the predetermined positions in the encrypted content key information to obtain concatenated data, performing a hash calculation with respect to the concatenated data to obtain a hash value, storing check values corresponding to the data at the predetermined positions in plain text, in the target apparatus, and storing the hash value in the target apparatus.
摘要:
A host information memory is provided in a semiconductor memory card and a data write start address and a data size supplied by an access unit are stored. A free physical area generation section determines whether or not to perform erasing of an invalid block of a nonvolatile memory when writing of data based on the data write start address and data size, and determines the number of blocks to be erased. When erasing, writing of data and erasing of invalid blocks are simultaneously performed with respect to different memory chips. Erase process of data, herewith, can be optimized and high speed access from the access unit to a semiconductor memory card can be realized.
摘要:
A region management method for an information recording medium capable of maintaining data interchangeability among devices and preventing malfunction when one information recording medium shared among devices different in type or number of file systems that can be interpreted by devices is provided. A recording region of the information recording medium is divided into a plurality of regions, and region information such as position and size of each region is held in the information recording medium. Different file systems are constructed in individual data recording regions. In response to a command from an information processing apparatus, accessible regions by the information processing apparatus are changed over by, for example, referring to validity flag information that indicates a presently valid region.
摘要:
A server apparatus includes a CPU, a RAM, a cipher processing unit for carrying out encryption and decryption, a communication processing unit for carrying out communication with an information processing terminal, and a data storage unit for storing information that does not require confidentiality. The server apparatus also includes a distribution information storage unit for storing information such as a program to be distributed, and a specific information distribution history holding unit for holding a specific information distribution history for managing a record of a program specific information of a program previously distributed to the information processing terminal.
摘要:
A semiconductor recording medium stores attribute management information for managing various attribute information on a content (genre, composer, artist, album, title, etc.) for each item; and sort management information managing information on a sort order when information managed by the attribute management information is sorted by a predetermined procedure. The attribute management information contains character data indicating items to be managed and pointer information indicating link relationship between the attribute management information. The sort management information contains information on the sort order when all the entries in each of attribute management information are sorted by a predetermined procedure for each of attribute management information.
摘要:
A system including a secure LSI 1 establishes a communication path to/from a server 3 (UD1), and receives a common key-encrypted program generated by encryption with a common key and transmitted from the server 3 (UD6 and UD7). The received common key-encrypted program is decrypted to generate a raw program, and the raw program is re-encrypted with an inherent key to newly generate an inherent key-encrypted program, which is stored in an external memory.
摘要:
Provided is a method for performing high-speed search for a content key associated with encrypted content in the case of a key-separation-type content management method where content keys and their respective pieces of encrypted content are correlated by ID information and stored in different recording media. An external recording medium is used to store a plurality of content files that contain: their respective pieces of encrypted content that are encrypted with different encryption keys; and their respective content IDs, each being associated with a corresponding piece of the encryption content, and a semiconductor recording medium is used to store a list that contains: pieces of encryption key storage location information, each indicating where a corresponding one of the encryption keys is stored; and the content IDs, the list being sorted in accordance with the content IDs. When encrypted content is played back, the list is searched to find encryption key storage location information associated with a content ID that matches the content ID of the encrypted content, and the encryption key is read based on the encryption key storage location information.
摘要:
A card information storage part (119) is provided in a semiconductor memory device (110) to store information of the characteristics of the semiconductor memory device (110). There is also provided a file system interface control part (120) for performing, based on the stored characteristic information, a file access suitable for the characteristics of the semiconductor memory device (110). This allows an access device (100) to perform an optimum file access via the file system interface control part (120) without awareness of the characteristics of the semiconductor memory device (110).
摘要:
A secure LSI device 1 includes an encryption section 2 for encrypting a program, and an external I/F 50 for inputting/outputting a program or data from/to an external memory 100. In the encryption section 2, the operation of a private key arithmetic processing section 20 is prohibited with respect to a sequence whose execution is determined by a key-generation/update sequencer 30 to be impermissible. In the external I/F 50, a program processing section 51 and a data processing section 55 are structured independently from each other.