Vehicle information collection system, vehicle-mounted computer, vehicle information collection device, vehicle information collection method, and computer program

1. A vehicle information collection system, comprising:

a vehicle information collection device configured to collect a log representing a record about an operation of an in-vehicle computer mounted on a vehicle, wherein the in-vehicle computer further comprises an interface configured to communicate with the vehicle information collection device, and

an encryption processor configured to generate a message authentication code about the log of the in-vehicle computer using a signature key and to generate an encrypted log by encrypting the log using an encryption key, thus transmitting the encrypted log annotated with the message authentication code to the vehicle information collection device via the interface,

wherein the vehicle information collection device further comprises

a vehicle interface configured to communicate with the in-vehicle computer to receive the encrypted log annotated with the message authentication code,

a key generator configured to generate the signature key using a master key, an identifier of the in-vehicle computer, and a first value determined in advance and the encryption key using the master key, the identifier of the in-vehicle computer, and a second value determined in advance,

an encryption processor configured to decrypt the encrypted log using the encryption key and to verify the message authentication code annotated to the encrypted log from the in-vehicle computer using the signature key, wherein the encryption processor is configured to generate a secondary message authentication code using the signature key with respect to the log decrypted from the encrypted log, and a storage media configured to store the log decrypted from the encrypted log when the message authentication code matches the secondary message authentication code.

2. A vehicle information collection device, comprising: a vehicle interface configured to communicate with an in-vehicle computer mounted on a vehicle to receive a message authentication code and an encrypted log produced by encrypting a log using an encryption key representing a record about an operation of the in-vehicle computer, and a processor configured to execute instructions stored on a memory, thus implementing:

generating a signature key using a master key, an identifier of the in-vehicle computer, and a first value determined in advance and the encryption key using the master key, the identifier of the in-vehicle computer, and a second value determined in advance;

decrypting the encrypted log from the in-vehicle computer using the encryption key and to verify the message authentication code annotated to the encrypted log from the in-vehicle computer using the signature key;

generating a secondary message authentication code using the signature key with respect to the log decrypted from the encrypted log; and

storing the log decrypted from the encrypted log when the message authentication code matches the secondary message authentication code.

3. A vehicle information collection method adapted to a vehicle information collection device and an in-vehicle computer mounted on a vehicle, comprising:

generating by the in-vehicle computer a message authentication code about a log representing a record about an operation of the in-vehicle computer using a signature key;

generating an encrypted log by encrypting the log using an encryption key;

transmitting by the in-vehicle computer the encrypted log annotated with the message authentication code to the vehicle information collection device;

receiving by the vehicle information collection device the encrypted log annotated with the message authentication code from the in-vehicle computer;

generating by the vehicle information collection device the signature key using a master key, an identifier of the in-vehicle, and a first value determined in advance and the encryption key using the master key, the identifier of the in-vehicle computer, and a second value determined in advance;

decrypting by the vehicle collection device the encrypted log using the encryption key;

verifying by the vehicle collection device the message authentication code annotated to the encrypted log from the in-vehicle computer using the signature key;

generating a secondary message authentication code using the signature key with respect to the log decrypted from the encrypted log; and

storing by the vehicle information collection device the log decrypted from the encrypted log when the message authentication code matches the secondary message authentication code on a storage media.

4. A non-transitory computer-readable storage medium having a stored computer program causing a computer to implement:

receiving an encrypted log annotated with a message authentication code from an in-vehicle computer mounted on a vehicle, wherein the encrypted log is produced by encrypting a log representing a record about an operation of the in-vehicle computer using an encryption key while the message authentication code is generated using a signature key with respect to the log of the in-vehicle computer;

generating the signature key using a master key, an identifier of the in-vehicle computer, and a first value determined in advance and the encryption key using the master key, the identifier of the in-vehicle computer, and a second value and determined in advance;

decrypting the encrypted log using the encryption key;

verifying the message authentication code annotated to the encrypted log from the in-vehicle computer using the signature key;

generating a secondary message authentication code using the signature key with respect to the log decrypted from the encrypted log; and

storing the log decrypted from the encrypted log on a storage media when the message authentication code matches the secondary message authentication code.