CRYPTOSYSTEM, CRYPTOGRAPHIC COMMUNICATION METHOD, ENCRYPTION DEVICE, KEY-GENERATING DEVICE, DECRYPTION DEVICE, CONTENT SERVER DEVICE, PROGRAM, AND RECORDING MEDIUM

摘要

Flexible operation is possible and provides an encrypted communication technique based on the function code. Attribute, which prescribes the conversion rules for converting the designated information to the conversion rule information and the logical expression specifying information for parameters, which prescribes the conversion rules for converting the attribute information used by the function code algorithm to logic information that is used for function encryption algorithm food conversion logic and rules of the Fair information Fair that is predetermined conversion rule information. Using the conversion rule information of the one included in the conversion rule information is attribute information or the first pair of the first logical information obtained from the input information. This information is used in the encryption process. In the decoding process, using the second attribute information or the second decryption key made by using the logical information obtained from the user information by using the conversion rule information of the other, it is subjected to decoding process of the encryption information. ;