TAG GENERATION DEVICE, TAG GENERATION METHOD, AND TAG GENERATION PROGRAM

摘要

Provided are a tag generation device, method and program which are capable of parallel execution, need no precomputation, and are capable of reducing block-cipher calls to the minimum necessary using one block cipher key when a tag to be attached to a message is generated. A tag generation device is provided with: an input means (100) which divides a message into a plurality of blocks; an intermediate chunk hash means (101) to which the blocks included in the message are inputted as an object to be processed, and which, in units of a predetermined number of blocks, using one key, executes encipherment processing and post-processing of encipherment on the blocks in parallel to generate an intermediate output, and designates, as a next object to be processed, a message created by coupling the intermediate output and unprocessed blocks; and a final chunk hash means (102) which, when the number of block in the message or the number of blocks in the message created by coupling the intermediate output and the unprocessed block is a predetermined value or less, generates a tag corresponding to the message.

主权项

1. A tag generation device comprising:
input unit which divides a message into a plurality of blocks; intermediate chunk hash unit which receives blocks included in the message as a processing target, performs encryption processing and post-processing of encryption for blocks using one key in units of a predetermined number of blocks in parallel to generate an intermediate output, and repeats the encryption processing and the post-processing of encryption on a message obtained by concatenating the intermediate output and unprocessed blocks as a next processing target; and last chunk hash unit which, in the case where the number of blocks of the message or the number of blocks of the message obtained by concatenating the intermediate output and the unprocessed blocks is less than or equal to a predetermined value, performs the encryption processing and the post-processing of encryption on the message to generate a tag.