| 摘要 |
<P>PROBLEM TO BE SOLVED: To suppress an increase of code size and to improve security of a program. <P>SOLUTION: A portable security device storing a program including a function and a command which invokes the function in a storage area comprises: a usable flag storage unit that stores the function stored in the program and a usable flag which shows whether the function is usable by the command by mapping each other for each command; and a usability determination unit that, when the function is invoked by the command according to an external instruction, determines whether the command invoking the function is usable for the function or not based on the usable flag mapped to the function. <P>COPYRIGHT: (C)2012,JPO&INPIT |
