Data-processing system and method for controlling same, computer program, and computer-readable recording medium

Abstract

A data-processing system and method for controlling synthesizing digital-signature information. The system and method include holding first private-key information, inputting second private-key information, generating third private-key information based on the first private-key information and the second private-key information, holding the third private-key information, generating signature information based on information to be verified and the third private-key information, and outputting the information to be verified and the signature information.

1 . A data-processing device comprising:
 a holding unit arranged to hold first private-key information which is managed in the data-processing device and is not released to a user;   an inputting unit arranged to input second private-key information which varies from one user to another, and public-key information;   a private-key-information generating unit arranged to generate third private-key information based on the first private-key information, the second private-key information, and the public-key information, wherein the generated third private-key information and the public-key information are paired off with each other in a public-key cryptosystem algorithm, and to store the third private-key information;   a signature-information generating unit arranged to generate signature information based on information to be verified and the third private-key information; and   an outputting unit arranged to output the information to be verified, the signature information, and the public-key information.   
   
   
       2 . A data-processing device according to  claim 1 , wherein the inputting unit further inputs certificate information used for authenticating the public-key information. 
   
   
       3 . A data-processing device according to  claim 2 , wherein the outputting unit outputs the information to be verified, the signature information, the public-key information, and the certificate information as a single file. 
   
   
       4 . A data-processing device according to  claim 1 , further comprising a generating unit for generating the information to be verified. 
   
   
       5 . A data-processing device according to  claim 1 , further comprising an image-pickup unit, wherein data on a predetermined image picked up by the image-pickup unit is generated as the information to be verified. 
   
   
       6 . A method for controlling a data-processing device, the method comprising:
 holding first private-key information which is managed in the data-processing device and is not released to a user;   inputting second private-key information which varies from one user to another, and public-key information;   generating third private-key information based on the first private-key information, the second private-key information, and the public-key information, wherein the generated third private-key information and the public-key information are paired off with each other in a public-key cryptosystem algorithm;   storing the third private-key information;   generating signature information based on information to be verified and the third private-key information; and   outputting the information to be verified, the signature information, and the public-key information.   
   
   
       7 . A method for controlling a data-processing device according to  claim 1 , further comprising inputting certificate information used for authenticating the public-key information. 
   
   
       8 . A method for controlling a data-processing device according to  claim 7 , further comprising outputting the information to be verified, the signature information, the public-key information, and the certificate information as a single file. 
   
   
       9 . A method for controlling a data-processing device according to  claim 6 , further comprising generating the information to be verified. 
   
   
       10 . A method for controlling a data-processing device according to  claim 6 , further comprising generating the information to be verified based on data on a predetermined image. 
   
   
       11 . A computer-readable storage medium storing a program for controlling a data-processing device, the program comprising:
 holding first private-key information which is managed in the data-processing device and is not released to a user;   inputting second private-key information which varies from one user to another, and public-key information;   generating third private-key information based on the first private-key information, the second private-key information, and the public-key information, wherein the generated third private-key information and the public-key information are paired off with each other in a public-key cryptosystem algorithm;   storing the third private-key information;   generating signature information based on information to be verified and the third private-key information; and   outputting the information to be verified, the signature information, and the public-key information.