| 摘要 |
PROBLEM TO BE SOLVED: To provide a technique capable of detecting alteration of associated non-encrypted data from encrypted data and makes normal decryption of encrypted data disabled when tampering is recognized. SOLUTION: A data distribution device 2 receives input data A and non-encrypted data B and uses a hash value calculated from the non-encrypted data B to perform block encryption processing of the input data A, and distributes encrypted data E(A) and the non-encrypted data B. The data distribution device includes: a data compression means 21, which uses a hash function to calculate a hash value from the non-encrypted data B; a block encryption processing means 22, which takes the hash value as an initial vector and subjects the input data A to block encryption processing, in a preliminarily determined use mode to generate encrypted data E(A); and a data distribution means 23, which multiplexes the encrypted data E(A) generated by the block encryption processing means and the non-encrypted data B to distribute a header, the non-encrypted data B, and the encrypted data E(A). COPYRIGHT: (C)2011,JPO&INPIT |
