摘要 |
An object of the present invention is to allow software to be securely updated when a volatile memory that will become a working area is not sufficiently large. An embedded apparatus sequentially performs a verification process on each of a plurality of sections obtained by division of update data for updating the software. The embedded apparatus stores an intermediate value obtained during the verification process. When the verification process is completed for each of the sections, the embedded apparatus compares a value obtained in the verification processes with verification data to check that there is no tampering. When it can be confirmed that there is no tampering, the embedded apparatus sequentially performs the verification process on each section again. The embedded apparatus compares an intermediate value obtained during the verification process with the intermediate value stored, and updates the software using the section when the intermediate value obtained and the intermediate value stored are the same. |