Information processing apparatus, server apparatus, medium recording information processing program and information processing method

• US 8,589,690 B2
• Filed: 08/26/2008
• Issued: 11/19/2013
• Est. Priority Date: 08/28/2007
• Status: Active Grant

• Current Assignee: Fujitsu Limited
• Original Assignee: Fujitsu Limited
• Inventors: Kassai, Kunihiko, Furuta, Toru
• Primary Examiner(s): Zand, Kambiz
• Assistant Examiner(s): KU, SHIUH-HUEI P
• Application Number:
  US12/198,335
• Publication Number:
  US 20090063853A1
• Time in Patent Office: 1,911 Days
• Field of Search: 713/150, 713/155, 713/156, 713/185, 713/189, 380/255, 380/277
• US Class Current: 713/176
• CPC Class Codes: H04L 9/0844 with user authentication or key authentication, e.g. ElGamal, MTI, MQV-Menezes-Qu-Vanstone protocol or Diffie-Hellman protocols using implicitly-certified keys

Abstract

A client PC 10 adapted to be connected to a server apparatus 20 has a first information transmission section that transmits an ID required for authentication by the server apparatus 20 to the server apparatus 20, a second information acquiring section that acquires a master key to be obtained as a result of being authenticated by the server apparatus 20 from the server apparatus 20, a cryptographic key generation section that generates a cryptographic key according to the first information and the second information, an encryption section that encrypts data by means of the cryptographic key and an encrypted data transmission section that transmits the encrypted data encrypted by the encryption section to the server apparatus 20.

Claims

1. An information processing apparatus adapted to be connected to a server apparatus, the information processing apparatus comprising:

a first information transmission section that transmits first information to the server apparatus for performing authentication;

a second information acquisition section that acquires second information to be obtained as a result of the authentication, from the server apparatus, the second information being encrypted by the server apparatus by using a first unique key held by the server apparatus;

a second information decryption section that decrypts the obtained second information by using a second unique key which is common to the first unique key and held by the information processing apparatus;

a cryptographic key generation section that generates a cryptographic key different from the second unique key, based on the first information and the decrypted obtained second information;

an encryption section that encrypts data to be transmitted to the server apparatus with the cryptographic key; and

an encrypted data transmission section that transmits the encrypted data to the server apparatus.

2. The information processing apparatus according to claim 1, further comprising:

an encrypted data acquisition section that acquires the encrypted data from the server apparatus; and

a decryption section that decrypts the encrypted data encrypted with the generated cryptographic key.

3. A server apparatus adapted to make cipher communications with an information processing apparatus, the server apparatus comprising:

a second information generation section that generates second information to be utilized for generation of a cryptographic key by the information processing apparatus;

an authentication section that authenticates the information processing apparatus by first information transmitted from the information processing apparatus;

a second information encryption section that encrypts the generated second information with a first unique key which is common to a second unique key of the information processing apparatus to decrypt the second information by the information processing apparatus;

a second information transmission section that transmits, to the information processing apparatus, the encrypted generated second information for generation by the information processing apparatus of the cryptographic key different from the second unique key; and

a data reception section that receives encrypted with the cryptographic key generated by the information processing apparatus based upon the first information and the decrypted generated second information.

4. The server apparatus according to claim 3, wherein the data reception section stores the received encrypted data.

5. The server apparatus according to claim 4, wherein the data reception section adds information according to the first information to the encrypted data and stores the encrypted data and the added information.

6. The server apparatus according to claim 4, wherein the data reception section transmits the stored encrypted data in response to a request.

7. The server apparatus according to claim 3,

wherein the second information generation section generates the second information with the clock time when the second information generation section is installed to the server apparatus.

8. A computer readable, non-transitory medium recording a program for causing a computer to execute a process for connecting to a server apparatus, the process comprising:

transmitting first information to the server apparatus for performing authentication;

acquiring second information obtained as a result of the authentication from the server apparatus, the second information being encrypted by the server apparatus by using a first unique key held by the server apparatus;

decrypting the obtained second information with a second unique key which is common to the first unique key;

generating a cryptographic key different from the second unique key, based on the first information and the decrypted obtained second information;

encrypting data to be transmitted to the server apparatus with the cryptographic key; and

transmitting the encrypted data to the server apparatus.

9. The non-transitory medium recording according to claim 8, the process further comprising:

acquiring the encrypted data; and

decrypting the encrypted data encrypted with the generated cryptographic key.

10. An information processing method for connecting to a server apparatus, the method comprising:

transmitting first information to the server apparatus for performing authentication;

acquiring second information obtained as a result of the authentication from the server apparatus, the second information being encrypted by the server apparatus by using a first unique key held by the server apparatus;

decrypting the second information with a second unique key which is common to the first unique key;

generating a cryptographic key different from the second unique key, based on the first information and the decrypted second information;

encrypting data to be transmitted to the server apparatus with the cryptographic key; and

transmitting the encrypted data to the server apparatus.

11. The information processing method according to claim 10, further comprising:

acquiring the encrypted data; and

decrypting the encrypted data encrypted with the generated cryptographic key.