PROGRAM

摘要

At the time of start of execution, a secure shared area for sharing between modules (#1) and (#2) is reserved upon memory, and key exchange is performed. By performing data exchange between modules (#1) and (#2) that have used the secure shared area through encryption/decryption processing using the key, access to the secure shared area from other than the modules (#1) and (#2) is disabled. When module (#1) calls module (#2), immediately before switching of the operation, an identifier indicating the module of the call destination is written to the secure shared area by a pre-switching processing unit. In the called module (#2), a post-switching processing unit compares the identifier that has been read out from the secure shared area with the identifier of the module itself, and if the two identifiers match, starts program execution. If the identifiers do not match, the module (#2) is made to enter into a sleep state.