| 摘要 |
<p>PROBLEM TO BE SOLVED: To provide a stream cipher device performing cipher processing matched with the number of bits of input data with a relatively simple circuit structure.SOLUTION: In a stream cipher processing unit 10 in a stream cipher device 1, a partial cipher circuit 20 has a plurality of storage units for storing key information of 8-bit therein, and a plurality of pieces of key information are associated with an address. Partial cipher circuits 20 to 23, within a period TC of a clock CLK, performs key information change processing for subsequently changing contents of a plurality of pieces of 8-bit key information to the address in order from the partial cipher circuits 20 to 23 to the partial cipher circuit 20 between the partial cipher circuits 20 to 23, executes transfer processing of a plurality of pieces of K-bit key information, and outputs a piece of information of the plurality of pieces of K-bit key information as key stream keys ZOUT0 to ZOUT3.</p> |
