Key generation apparatus and key update method
AssigneeFujitsu Limited
InventorsKoichi Yasaki, Tadanobu Tsunoda, Kazuaki Nimura
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Abstract
A key generation apparatus includes a memory, a communication interface, and a processor. The memory stores a first private key corresponding to a first public key. The communication interface communicates with a peer apparatus that stores the first public key. The processor generates a second public key and a second private key in response to a key update request from the peer apparatus, generates a digital signature by encrypting data including the second public key with the first private key, and sends a message including the data and the digital signature to the peer apparatus. In addition, the processor switches the first private key to the second private key.
Claims6
A key generation apparatus comprising:
- a memory configured to store a first private key corresponding to a first public key;
- a communication interface configured to communicate with a peer apparatus that stores the first public key;
- and
- a processor configured to generate a second public key and a second private key in response to a key update request from the peer apparatus, generate a digital signature by encrypting data including the second public key with the first private key, send a message including the data and the digital signature to the peer apparatus via the communication interface, and switch the first private key to the second private key;
- and
- when the peer apparatus authenticates the key generation apparatus, the processor sends the message via the communication interface in response to a challenge message from the peer apparatus, the challenge message includes key specification information that specifies a private key to be used,
- wherein when the key specification information specifies the first private key, the processor sends the message via the communication interface, and
- when the key specification information specifies the second private key, the processor generates a different digital signature by encrypting the challenge message with the second private key and sends a different message including the different digital signature to the peer apparatus via the communication interface.
A key update method comprising:
- generating, by a processor included in a computer, a second public key and a second private key in response to a key update request from a peer apparatus storing a first public key corresponding to a first private key stored in the computer;
- generating, by the processor, a digital signature by encrypting data including the second public key with the first private key and sending a message including the data and the digital signature to the peer apparatus;
- switching, by the processor, the first private key to the second private key;
- when the peer apparatus authenticates the key generation apparatus, sending, by the processor, the message in response to a challenge message from the peer apparatus, the challenge message includes key specification information that specifies a private key to be used, wherein when the key specification information specifies the first private key, sending by the processor the message via the communication interface, and
- when the key specification information specifies the second private key, generating by the processor a different digital signature by encrypting the challenge message with the second private key and sending a different message including the different digital signature to the peer apparatus.
A non-transitory computer-readable recording medium storing therein a computer program that causes a computer to execute a process comprising:
- generating a second public key and a second private key in response to a key update request from a peer apparatus storing a first public key corresponding to a first private key stored in the computer;
- generating a digital signature by encrypting data including the second public key with the first private key and sending a message including the data and the digital signature to the peer apparatus;
- switching the first private key to the second private key;
- when the peer apparatus authenticates the key generation apparatus, sending, by the processor, the message in response to a challenge message from the peer apparatus, the challenge message includes key specification information that specifies a private key to be used, wherein when the key specification information specifies the first private key, sending by the processor the message via the communication interface, and
- when the key specification information specifies the second private key, generating by the processor a different digital signature by encrypting the challenge message with the second private key and sending a different message including the different digital signature to the peer apparatus.
Dependencies are inferred from the claim text.