摘要 |
According to one embodiment, the cryptographic operation apparatus performs a cryptographic operation using first and second key data and includes an initial mask value creating unit that creates the initial mask value using the second key data and data information. In addition, the cryptographic operation apparatus further includes a mask value updating unit that creates the mask value using the initial mask value and a mask value storing unit that stores and outputs the initial mask value and the created mask value. In addition, the encryption is performed using the input data, the first key data, and the output mask value. |