KEY SEQUENCE OUTPUT DEVICE, STREAM CIPHER ENCRYPTION DEVICE, STREAM CIPHER DECRYPTION DEVICE, KEY SEQUENCE OUTPUT METHOD, AND PROGRAM

摘要

PROBLEM TO BE SOLVED: To provide a key sequence output device of a stream cipher capable of efficient update of an internal memory.;SOLUTION: A key sequence output device 10 for outputting a key sequence for processing a stream cipher comprises: an internal memory 100 for storing an initial key and an initial vector as initial values in a register; an internal memory update unit 110 for updating the values stored in the register of the internal memory 100; a key sequence output unit 120 for outputting a key sequence generated from the values stored in the register of the internal memory 100; and a switch Sb 210 for controlling connection between the internal memory 100 and the key sequence output unit 120. When updating by the internal memory update unit 110 the values stored in the register of the internal memory 100 without outputting the key sequence by the key sequence output unit 120, the switch Sb 210 is turned on.;COPYRIGHT: (C)2013,JPO&INPIT