| 摘要 |
To provide an encryption instruction processing apparatus which makes it possible to reliably prevent fraud analysis of a program, encrypt only part of the program requiring protection so as to reduce a decryption time in a simple manner, and suppress increase in a hardware size, an encryption instruction processing apparatus is formed so that the apparatus includes an instruction decryption section and a decryption key storage section and decryption keys are stored in the encryption key storage section. Each of encryption extended instruction codes to be processed by the encryption instruction processing apparatus includes an instruction code and an instruction encryption identifier indicating whether or not the instruction code is encrypted. The instruction codes are encrypted according to the degree of confidentiality of each instruction code. In executing a program, according to a value for an instruction encryption identifier, the instruction decryption section decrypts an instruction code using the decryption key. |
