摘要 |
An encryption device (100), wherein a division unit (130) determines the number of blocks that are encrypted using the same key as a processing unit, and divides plaintext data inputted from a second input unit (120) by the processing unit. An encryption unit (150) generates, from a common key inputted from a first input unit (110), a same number of mutually different processing keys (1-N) as the number of divisions (N) of plaintext data divided by the division unit (130), and generates encrypted data for each processing unit determined by the division unit (130) by encrypting each block of the plaintext data inputted from the second input unit (120) with a block cryptogram (F) by using a generated same processing key I (I = 1, 2, ..., N). |