NON-TRANSITORY COMPUTER READABLE MEDIUM STORING PROGRAM, INFORMATION PROCESSING APPARATUS, AND INFORMATION PROCESSING METHOD

• US 20120017092A1
• Filed: 01/14/2011
• Published: 01/19/2012
• Est. Priority Date: 07/14/2010
• Status: Active Grant

• Current Assignee: Fuji Xerox Company Limited (Xerox Holdings Corp.)
• Original Assignee: Fuji Xerox Company Limited (Xerox Holdings Corp.)
• Inventors: YOKOE, Kyoko
• Granted Patent: US 8,499,162 B2
• Time in Patent Office: Days
• US Class Current: 713/178
• CPC Class Codes: H04L 9/3236 using cryptographic hash functions
• CPC Class Codes: H04L 9/3247 involving digital signatures
• CPC Class Codes: H04L 9/3263 involving certificates, e.g. public key certificate [PKC] or attribute certificate [AC]; Public key infrastructure [PKI] arrangements network architectures or network communication protocols for supporting authentication of entities using certificates in a packet data network H04L63/0823
• CPC Class Codes: H04L 9/3297 involving time stamps, e.g. generation of time stamps

Abstract

A non-transitory computer readable medium storing a program causing a computer to execute a process including: accepting an instruction for verifying an electronic signature added to information; verifying the electronic signature on the basis of an electronic certification corresponding to the electronic signature in accordance with the accepted instruction; calculating, when it is determined that the information has not been tampered with, a hash value of a combination of the information, the electronic signature, and validity-period information indicating a validity period of the electronic certification; adding a time stamp to the calculated hash value; outputting the information, the electronic signature, the hash value, and the validity-period information to a storage device; and outputting, when it is determined that the information has not been tampered with, a verification result including information indicating that the information has not been tampered with.

Claims

1. A non-transitory computer readable medium storing a program causing a computer to execute a process, the process comprising:

accepting an instruction for performing verification of an electronic signature which is added to information;

verifying the electronic signature on the basis of an electronic certification corresponding to the electronic signature in accordance with the accepted instruction;

calculating, when it is determined that the information to which the verified electronic signature is added has not been tampered with, a hash value of a combination of the information, the electronic signature which is added to the information, and validity-period information indicating a validity period of the electronic certification corresponding to the electronic signature;

adding a time stamp to the calculated hash value;

outputting, to a storage device, the information to which the verified electronic signature is added, the electronic signature, the hash value to which the time stamp has been added, and the validity-period information so that the information, the electronic signature, the hash value, and the validity-period information correspond to one another; and

outputting a verification result when it is determined that the information to which the verified electronic signature is added has not been tampered with, the verification result including information indicating that the information has not been tampered with.

2. The non-transitory computer readable medium according to claim 1, the process further comprising:

acquiring the hash value and the validity-period information, which correspond to the information to which the verified electronic signature is added, from the storage device in accordance with the accepted instruction;

determining whether or not the electronic certification is presently within the validity period indicated by the validity-period information which has been acquired; and

verifying, when it is determined that the electronic certification is presently within the validity period, a hash value to which a time stamp is added,

wherein, when it is determined, in the verifying of a hash value, that the combination has not been tampered with, a verification result including information indicating that the information to which the verified electronic signature is added has not been tampered with is output in the outputting of a verification result.

3. The non-transitory computer readable medium according to claim 1,

wherein, when the electronic certification includes a plurality of electronic certifications, a hash value is calculated, in the calculating of a hash value, using validity-period information indicating the shortest validity period among validity periods of the plurality of electronic certifications.

4. The non-transitory computer readable medium according to claim 2,

wherein, when the electronic certification includes a plurality of electronic certifications, a hash value is calculated, in the calculating of a hash value, using validity-period information indicating the shortest validity period among validity periods of the plurality of electronic certifications.

5. An information processing apparatus comprising:

an acceptance unit that accepts an instruction for performing verification of an electronic signature which is added to information;

a verification unit that verifies the electronic signature on the basis of an electronic certification corresponding to the electronic signature in accordance with the instruction which has been accepted by the acceptance unit;

a hash-value calculation unit that calculates, when it is determined that the information to which the electronic signature verified by the verification unit is added has not been tampered with, a hash value of a combination of the information, the electronic signature which is added to the information, and validity-period information indicating a validity period of the electronic certification corresponding to the electronic signature;

a time-stamp addition unit that adds a time stamp to the hash value which has been calculated by the hash-value calculation unit;

a unit that outputs, to a storage device, the information to which the verified electronic signature is added, the electronic signature, the hash value to which the time stamp has been added by the time-stamp addition unit, and the validity-period information so that the information, the electronic signature, the hash value, and the validity-period information correspond to one another; and

a verification-result output unit that outputs a verification result when it is determined that the information to which the electronic signature verified by the verification unit is added has not been tampered with, the verification result including information indicating that the information has not been tampered with.

6. An information processing method comprising:

accepting an instruction for performing verification of an electronic signature which is added to information;

verifying the electronic signature on the basis of an electronic certification corresponding to the electronic signature in accordance with the accepted instruction;

calculating, when it is determined that the information to which the verified electronic signature is added has not been tampered with, a hash value of a combination of the information, the electronic signature which is added to the information, and validity-period information indicating a validity period of the electronic certification corresponding to the electronic signature;

adding a time stamp to the calculated hash value;

outputting, to a storage device, the information to which the verified electronic signature is added, the electronic signature, the hash value to which the time stamp has been added, and the validity-period information so that the information, the electronic signature, the hash value, and the validity-period information correspond to one another; and

outputting a verification result when it is determined that the information to which the verified electronic signature is added has not been tampered with, the verification result including information indicating that the information has not been tampered with.