Electronic information storage medium, IC chip, IC card, method for setting expiration date of key data, and program

Abstract

To provide an electronic information storage medium, an IC chip, an IC card, a method for setting the expiration date of key data, and a program that are capable of efficiently setting the expiration date of a common key used in encryption calculations by a common key encryption method.SOLUTION: Upon receiving a write command for second key data (common key) used in a predetermined common key encryption method from an external device 2, an IC chip 1 sets the expiration date of the second key data, based on an encryption strength list, and the expiration date of first key data (for example, a key pair of a private key and a public key) stored in an NVM 13 when writing the second key data to be registered to the NVM 13 in accordance with the write command.SELECTED DRAWING: Figure 3