| 摘要 |
<P>PROBLEM TO BE SOLVED: To take a countermeasure against attacks employing differential power analysis using side channel information or analysis of an electromagnetic wave or the like and to suppress the increase of circuit scale. <P>SOLUTION: An encryption processing device includes: a division unit which divides input data being a plaintext or a result of round processing into a plurality of pieces of partial data; a plurality of data holding units for holding the plurality of pieces of partial data respectively; and a coupling unit which couples the plurality of pieces of partial data held in the plurality of data holding units, to one piece of round processing object data that is subject to round processing. The division unit selects respective storage destinations of the plurality of pieces of partial data from among the plurality of data holding units and stores the plurality of pieces of partial data in the selected storage destinations respectively. In accordance with the storage destinations of respective pieces of partial data, which are selected by the division unit, the coupling unit couples the plurality of pieces of partial data to the round processing object data so as to restore input data. <P>COPYRIGHT: (C)2012,JPO&INPIT |
