| 摘要 |
<P>PROBLEM TO BE SOLVED: To provide a portable electronic device and an IC card, which can make output data of an encryption processing result unpredictable, so that the encryption processing result becomes difficult to predict, and further becomes difficult to guess even if a parameter used for encryption processing is altered. <P>SOLUTION: In the IC card including a memory for storing data and a means which has a control element for writing or reading data to the memory and selectively performs input and output of data with the outside, a random number is stored in a coprocessor memory for temporarily holding processing data in encryption processing prior to the execution of encryption processing, whether the random number is properly stored in the coprocessor memory is confirmed prior to the execution of encryption processing, and when the random number is not properly stored in the coprocessor memory as a result of the confirmation, error processing is performed without performing the encryption processing. <P>COPYRIGHT: (C)2010,JPO&INPIT |
