| 摘要 |
PROBLEM TO BE SOLVED: To provide a security token capable of preventing a scramble key used for encrypting security data from being leaked out. SOLUTION: An IC chip 2 including a ROM 22 whose data is inhibited from being read to the outside and an electrically rewritable EEPROM 23 is mounted on an IC card 1, wherein the ROM 22 stores an encryption key seed 12 for deriving a scramble key, and the EEPROM 23 stores definition information 13 for defining one scramble key out of scramble keys derived from the encryption key seed 12. An encryption module 10 mounted on the ROM 22 of the IC card 1 derives, when executing processing that encrypts data and writes the data in the EEPROM 23, one scramble key defined by the definition information 13 from the encryption key seed 12 according to a predetermined derived algorithm and uses the scramble key to encrypt the data. COPYRIGHT: (C)2011,JPO&INPIT |
