Authentication processing apparatus, authentication processing system, authentication processing method and authentication processing program

An authentication processing apparatus in an authentication processing system,

• the authentication processing system including:
• a target device that generates target information to be authenticated;
• a certificate verifying apparatus that verifies an electronic certificate for the target device;
• and
• the authentication processing apparatus that, using a verification result by the certificate verifying apparatus, authenticates the target information;
• the certificate verifying apparatus receiving from the authentication processing apparatus certificate information relating to the electronic certificate for the target device, verifying whether or not the electronic certificate for the target device is valid with reference to verification-use reference information stored in advance, generating authentication-use reference information which includes the verification result, and sending the authentication-use reference information to the authentication processing apparatus;
• the authentication processing apparatus comprising:
• a target-information receiving circuit that receives from the target device the target information,
• a digital signature for the target information, and
• the certificate information relating to an electronic certificate issued for a target device that generates the target information;
• a certificate-verification requesting circuit that sends to the certificate verifying apparatus the certificate information received by the target-information receiving circuit, and receives the authentication-use reference information from the certificate verifying apparatus;
• and
• a signature verifying circuit,
• when the verification result included in the authentication-use reference information received by the certificate-verification requesting circuit indicates validity,
• using a public key of the target device, which is included in the electronic certificate for the target device, and the target information received by the target-information receiving circuit,
• verifies whether or not the digital signature for the target information received by the target-information receiving circuit is valid.