Functional encryption applied system, information output apparatus, information processing apparatus, encryption protocol execution method, information output method, information processing method, program and recording medium

摘要

An information output apparatus identifies, according to a rule established for each of functional encryption protocols or a rule established for each combination of the protocols, one or more identifiers corresponding to a particular functional encryption protocol or a combination of the particular protocols, sets a particular piece of first correspondence information corresponding to the identifier or identifiers, and outputs first information which is a ciphertext or key information of the functional encryption scheme that corresponds to the particular piece of first correspondence information. An information processing apparatus inputs the first information and second information which is key information or a ciphertext of the functional encryption scheme that corresponds to a particular piece of second correspondence information into a decryption function of the functional encryption scheme and, when the truth value of a logical formula corresponding to the combination of the particular piece of first correspondence information corresponding to the first information and the particular piece of second correspondence information corresponding to the second information is true, generates a decryption result.

主权项

1. A functional encryption applied system comprising an information output apparatus and an information processing apparatus, wherein
the information output apparatus includes: a determiner that identifies a first identifier or a plurality of first identifiers according to a rule for a combination of protocols or each of the protocols that are in accordance with a functional encryption scheme, the first identifier or the plurality of the first identifiers corresponding to the protocols or each of the protocols; a setter that sets a particular piece of first correspondence information corresponding to the first identifier or a combination of the plurality of the first identifiers; and a transmitter that outputs first information, the first information being a first ciphertext or first key information of the functional encryption scheme, and the first information corresponding to the particular piece of first correspondence information, the information processing apparatus includes: a decryptor that inputs the first information and second information corresponding to a particular piece of second correspondence information into a decryption function of the functional encryption scheme and, generating a decryption result when a truth value of a logical formula corresponding to a combination of the particular piece of first correspondence information and the particular piece of second correspondence information is true, the second information being second key information of the functional encryption scheme when the first information is the first ciphertext, and the second information being a second ciphertext of the functional encryption scheme when the first information is the first key information, the particular piece of second correspondence information corresponding to a second identifier or a combination of a plurality of second identifiers, the second identifier or the second identifiers being identified in according to the rule, the information output apparatus further comprises a first selector that selects whether the first information is to be the first ciphertext or the first key information, depending on the protocol or each of the protocols, the first key information being used for decryption of the second ciphertext, the second ciphertext being generated without the first key information; the information processing apparatus further comprising a second selector that selects whether the second information is to be the second ciphertext or the second key information, depending on the protocol or each of the particular protocols, the second key information being used for decryption of the first ciphertext, the first ciphertext being generated without the second key information; and the first correspondence information is a first vector or first vectors, and the second correspondence information is a second vector or second vectors.