| 摘要 |
PROBLEM TO BE SOLVED: To provide a decryption device, a method, and a program in which decryption processing in RSA encryption is safe and high speed.SOLUTION: When decrypting RSA encryption, a decryption device 10 generates a random number by a random number generation unit 11, derives each bit of a secret key by operation in which operation of exclusive OR including a plurality of different random numbers and secret keys is mixed in a decryption calculation unit 12, determines the value of each derived bit from the most significant bit or the least significant bit of the secret key in order, and performs modular exponentiation calculation for decryption by repeating square multiplication and multiplication in accordance with determination results. The decryption device 10 further includes a protection storage unit 30 having an access pattern protection unit 31 and uses a stored secrete key for the protection storage unit 30.SELECTED DRAWING: Figure 2 |
