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:
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:
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 domain key is used to perform chaining decryption with respect to encrypted content key information (ST203-1), and first data is extracted (ST203-2). The extracted first data is compared with partial-check data (ST203-4). The first data as it is encrypted is extracted from the m pieces of encrypted content key information (ST203-6), and a predetermined operation is executed with respect to concatenated data including m extracted check values to generate second data (ST203-8). The second data is compared with whole-check data included in domain key information (ST203-11). If the first data matches the partial-check data (ST203-5) and the second data matches the whole-check data (ST203-12), it is determined that there is not tampering.