Authenticator, authenticatee and authentication method

摘要

According to one embodiment, an authentication method between an authenticatee which stores key information having a data structure composed of a key transition record, secret information XY of a matrix form, and secret information XYE which is created by encrypting the secret information XY, and an authenticator which authenticates the authenticatee, includes selecting, by the authenticator, a record corresponding to a device index of the authenticator from the key information which is received from the authenticatee, and decrypting the record by a device key, thereby taking out a key transition, and executing, by the authenticator, a decryption process on the secret information XYE, which is received from the authenticatee, by using the corresponding key transition, and sharing the secret information XY.

主权项

1. An authentication method between an authenticatee device having a first memory which stores key information having a data structure composed of encrypted slot key sequences, secret information of a matrix form, and encrypted secret information which is created by encrypting the secret information, and an authenticator device having a second memory which authenticates the authenticatee device, comprising:
receiving, by the authenticator device, the encrypted secret information and the key information; selecting an encrypted slot key sequence corresponding to a device index stored in the second memory of the authenticator device from the encrypted slot key sequences in the key information received from the authenticatee device, the device index corresponding to the authenticator device; decrypting the encrypted slot key sequence by a device key stored in the second memory, to produce a sequence of a slot index and a slot key; selecting, by the authenticator device, an element corresponding to the slot index from the encrypted secret information; executing, by the authenticator device, a decryption process on the element of the encrypted secret information by using the slot key to produce an element of the secret information; using a compression arithmetic circuit in the authenticatee device to perform an arithmetic operation on the element and produce an authentication value; and authenticating the authenticatee device using the authentication value.