The stream cryptography encryption device, the decoding device and the MAC generation device, stream cryptography encryption manner and decoding manner, inputting the MAC generation method

摘要

PROBLEM TO BE SOLVED: To enhance the security of existing streaming cipher without adding different logic.;SOLUTION: A ciphering device for stream cipher includes: a first initialization processing means receiving the input of an initial key and an initial vector to perform initialization processing; a first key sequence generation processing means performing key sequence generation processing to generate a key sequence having the data length equivalent to the initial key and the initial vector; a second initialization processing means performing the initialization processing by regarding the generated key sequence as a new initial key; a second key sequence generation processing means performing the key sequence generation processing to generate a key sequence having the data length equivalent to a plaintext; and an exclusive OR operation means performing the exclusive OR operation of bit data of the generated key sequence and the plaintext to output a ciphertext.;COPYRIGHT: (C)2010,JPO&INPIT