Information Processing Apparatus, Information Processing System, Information Processing Method, and Program

Abstract

To prevent a participant user from denying afterwards.SOLUTION: According to the present invention, an information processing device includes electronic certificate acquisition means for acquiring an electronic certificate, signature file acquisition means for acquiring a signature file, electronic signature creation means for creating an electronic signature from the signature file by using the electronic certificate, time stamp acquisition means for acquiring a time stamp related to the signature file, the electronic signature, and the electronic certificate, and storage file output means for outputting a storage file including the signature file, the electronic signature, the electronic certificate, and the time stamp.SELECTED DRAWING: Figure 1

Description

Technical Field

[0001] The present invention relates to the processing of electronic data such as online meetings.

Background Art

[0002] Patent Document 1 discloses a technique for managing the storage period of electronic documents.

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0004] Archive log files, which are electronic data of online calls and online meetings, are expected to prevent participating users from denying them later. However, Patent Document 1 does not disclose a mechanism for preventing participating users from denying them later.

[0005] An object of the present invention is to provide an information processing apparatus and the like that prevent participating users from denying later.

Means for Solving the Problems

[0006] An information processing apparatus according to one embodiment of the present invention includes an electronic certificate acquisition unit that acquires an electronic certificate, a signature file acquisition unit that acquires a signature file, an electronic signature creation unit that creates an electronic signature from the signature file using the electronic certificate, a timestamp acquisition unit that acquires a timestamp related to the signature file, the electronic signature, and the electronic certificate, and a storage file output unit that outputs a storage file including the signature file, the electronic signature, the electronic certificate, and the timestamp.

[0007] In one aspect of the present invention, an information processing system includes the above-described information processing device, and a server that, when receiving a request for a signature file from the information processing device, transmits the signature file to the information processing device, and when receiving a storage file from the information processing device, verifies the validity of the electronic signature, electronic certificate, and time stamp included in the storage file, and stores the storage file when all of the electronic signature, electronic certificate, and time stamp are valid.

[0008] An information processing method according to one aspect of the present invention includes obtaining an electronic certificate, obtaining a signature file, creating an electronic signature from the signature file using the electronic certificate, obtaining a time stamp related to the signature file, the electronic signature, and the electronic certificate, and outputting a storage file including the signature file, the electronic signature, the electronic certificate, and the time stamp.

[0009] A program according to one aspect of the present invention causes a computer to execute a process of obtaining an electronic certificate, a process of obtaining a signature file, a process of creating an electronic signature from the signature file using the electronic certificate, a process of obtaining a time stamp related to the signature file, the electronic signature, and the electronic certificate, and a process of outputting a storage file including the signature file, the electronic signature, the electronic certificate, and the time stamp.

Advantages of the Invention

[0010] According to the present invention, it is possible to achieve the effect of preventing participating users from denying at a later time.

Brief Description of the Drawings

[0011]

Figure 1

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Embodiments for Carrying Out the Invention

[0012] As a record of a meeting or the like, an archive log file including voice in an online call or an archive log file including voice and video in an online meeting is stored. When storing an archive log file as a record of an online meeting or the like, it is desirable that the archive log file has a mechanism to prevent a participating user from later denying participation in the meeting or denying the content of the meeting. Therefore, the information processing apparatus according to the embodiment of the present invention creates an archive log file having a mechanism to prevent a participating user from later denying, using an electronic signature or the like, as described below. The information processing apparatus of each embodiment uses, as the archive log file, an archive log file of an online call or an online meeting, but is not limited thereto, and other files may be used. Note that the information processing apparatus attaches an electronic signature or the like to the acquired archive log file. Therefore, the file acquired by the information processing apparatus and attached with a signature or the like is hereinafter referred to as a signature file.

[0013] FIG. 1 is a block diagram showing an example of the configuration of an information processing apparatus 10 according to the first embodiment. The information processing apparatus 10 includes an electronic certificate acquisition unit 110, a signature file acquisition unit 120, an electronic signature creation unit 130, a time stamp acquisition unit 140, and a storage file output unit 150.

[0014] The electronic certificate acquisition unit 110 acquires an electronic certificate. For example, the electronic certificate acquisition unit 110 acquires an electronic certificate issued for the public key of the public-key cryptography used by the information processing apparatus 10 from a certification authority (CA: Certificate Authorities). At that time, the electronic certificate acquisition unit 110 may transmit the public key to the CA, or may output the uniform resource locator (URL: Uniform Resource Locator) of the key server that stores the public key. A CA is an organization that issues electronic certificates. An electronic certificate is electronic data issued by a CA and electronically proves that the person is undoubtedly the individual. Public-key cryptography is a cryptographic method that uses different keys for encryption and decryption and allows one of the keys to be made public.

[0015] The signature file acquisition unit 120 acquires a signature file. For example, the signature file acquisition unit 120 acquires an archive log file as a signature file from a server that manages the meetings the user has participated in, in order to store it as the minutes of the meetings the user has participated in. Alternatively, the signature file acquisition unit 120 may acquire the archive log file stored in a storage device (not shown).

[0016] The electronic signature creation unit 130 creates an electronic signature from the signature file using the electronic certificate. An electronic signature is a credential attached to electronic data and serves the same role as a signature or seal on a paper document. An electronic signature is generally realized using public-key cryptography. Therefore, for example, the electronic signature creation unit 130 first calculates the hash value of the signature file. Hereinafter, the hash value of the signature file is referred to as the "first hash value". Then, the electronic signature creation unit 130 encrypts the first hash value using the private key corresponding to the public key used for the issuance of the electronic certificate to create an electronic signature.

[0017] The time stamp acquisition unit 140 acquires time stamps related to the signature file, the electronic signature, and the electronic certificate. For example, the time stamp acquisition unit 140 treats the signature file, the electronic signature, and the electronic certificate as a continuous data as the hash value for the time stamp, and calculates the hash value of the data. Hereinafter, the hash value for the time stamp is referred to as the "second hash value". Then, the time stamp acquisition unit 140 uses the second hash value to acquire a time stamp from a time stamping authority (TSA). The TSA is an organization that issues time stamps. A time stamp is to prove that the electronic data existed at the time of the time stamp (existence proof) and that it has not been tampered with after that time (non-tampering proof). The time stamp acquisition unit 140 may acquire time stamps for the signature file, the electronic signature, and the electronic certificate respectively from the TSA. For example, the time stamp acquisition unit 140 calculates the hash value for each of the signature file, the electronic signature, and the electronic certificate as the second hash value. Then, the time stamp acquisition unit 140 may use the calculated hash value to acquire the time stamps for the signature file, the electronic signature, and the electronic certificate respectively from the TSA.

[0018] The save file output unit 150 outputs a save file including a signature file, an electronic signature, an electronic certificate, and a time stamp. For example, the save file output unit 150 creates an archive log file that combines a signature file, an electronic signature, an electronic certificate, and a time stamp as a save file using a preset file wrapping method. File wrapping means combining a plurality of electronic data into a file in a format that allows integrated processing. The save file output unit 150 may create an archive log file in which the data is compressed. Then, the save file output unit 150 outputs the created archive log file as a save file to the server that transmitted the signature file. Alternatively, the save file output unit 150 may save the save file in a storage device (not shown). FIG. 2 is a diagram showing an example of a save file. The save file in FIG. 2 is an archive log file that combines a signature file, an electronic signature, an electronic certificate, and a time stamp using a preset file wrapping method.

[0019] FIG. 3 is a flowchart showing an example of the operation of the information processing apparatus 10. Note that the information processing apparatus 10 has already saved a secret key prior to the following operations. For example, a user of the information processing apparatus 10 may save a secret key in the information processing apparatus 10. Alternatively, the information processing apparatus 10 may acquire a secret key from a key server. The information processing apparatus 10 may save a public key. The electronic certificate acquisition unit 110 acquires an electronic certificate (step S201). For example, the electronic certificate acquisition unit 110 acquires an electronic certificate issued by a CA for the public key. The electronic certificate acquisition unit 110 may save the acquired electronic certificate in preparation for the next process. When an electronic certificate corresponding to the public key is saved, the electronic certificate acquisition unit 110 confirms that the electronic certificate is valid, and if it is valid, may use the saved electronic certificate. The signature file acquisition unit 120 acquires a signature file (step S202). For example, the signature file acquisition unit 120 acquires a signature file, which is an archive log file such as the audio and video of a meeting, from a server that manages an online meeting. The electronic signature creation unit 130 creates an electronic signature using the electronic certificate (step S203). For example, the electronic signature creation unit 130 encrypts the first hash value of the signature file using the secret key for the public key used for issuing the electronic certificate to create an electronic signature. The timestamp acquisition unit 140 acquires a timestamp related to the signature file, the electronic signature, and the electronic certificate (step S204). For example, the timestamp acquisition unit 140 transmits the second hash value calculated using the signature file, the electronic signature, and the electronic certificate to the TSA, and acquires a timestamp for the second hash value from the TSA. The storage file output unit 150 outputs a storage file including the signature file, the electronic signature, the electronic certificate, and the timestamp (step S205). For example, the storage file output unit 150 creates a storage file including the signature file, the electronic signature, the electronic certificate, and the timestamp, and outputs the storage file to the server that transmitted the signature file.

[0020] As described above, the information processing apparatus 10 includes an electronic certificate acquisition unit 110, a signature file acquisition unit 120, an electronic signature creation unit 130, a time stamp acquisition unit 140, and a storage file output unit 150. The electronic certificate acquisition unit 110 acquires an electronic certificate. The signature file acquisition unit 120 acquires a signature file. The electronic signature creation unit 130 creates an electronic signature from the signature file using the electronic certificate. The time stamp acquisition unit 140 acquires a time stamp related to the signature file, the electronic signature, and the electronic certificate. The storage file output unit 150 outputs a storage file including the signature file, the electronic signature, the electronic certificate, and the time stamp.

[0021] The information processing apparatus 10 outputs a storage file including a signature file, an electronic signature, an electronic certificate, and a time stamp. For example, in response to a request for approval of an archive log file from a server that manages an online meeting in which a user participated, the information processing apparatus 10 acquires the archive log file as the signature file. Then, the information processing apparatus 10 operates as described above and outputs a storage file in which the electronic certificate, the electronic signature, and the time stamp are wrapped around the archive log file. Therefore, the user of the storage file can prevent the participating user from denying participation in the meeting or denying the meeting content based on the electronic certificate, the electronic signature, and the time stamp included in the storage file. For example, the user of the storage file can prevent the participating user from denying participation in the meeting based on the electronic certificate and the electronic signature. Also, the user of the storage file can prevent denial of the meeting content based on the signature file, the electronic signature, and the time stamp. Thus, the information processing apparatus 10 outputs a file that prevents the participating user from denying participation or the like. That is, the information processing apparatus 10 creates a file that more appropriately ensures the integrity of, for example, the archive log file.

[0022] <Variation> 1. Modification of the Signature File The information processing apparatus 10 may create a file for storage after modifying the file for signature. In this case, the information processing apparatus 10 may create an electronic signature for the modified file, obtain a time stamp, and create a file for storage. Note that the information processing apparatus 10 may create a file for storage including the file for signature before modification. FIG. 4 is a diagram showing an example of a file for storage including the file for signature before modification and the file after modification.

[0023] 2. Revision of the File for Storage The information processing apparatus 10 may revise the file included in the output file for storage to revise the file for storage. For example, the information processing apparatus 10 may operate as follows. The information processing apparatus 10 obtains the output file for storage. For example, the signature file acquisition unit 120 obtains the file for storage from the server storing the file for storage. Then, the information processing apparatus 10 modifies the signature file of the obtained file for storage. After modifying the signature file, the electronic certificate acquisition unit 110 re-obtains an electronic certificate. Then, the electronic signature creation unit 130 re-creates an electronic signature from the modified file. Then, the time stamp acquisition unit 140 re-obtains a time stamp related to the modified file, the re-created electronic signature, and the re-obtained electronic certificate. Then, the file for storage output unit 150 outputs a modified file for storage including the modified file, the re-created electronic signature, the re-obtained electronic certificate, and the re-obtained time stamp.

[0024] Note that the information processing apparatus 10 may include at least a part of the information included in the file for saving before the correction in the file for saving after the correction. For example, the information processing apparatus 10 may include all of the information of the file for saving before the correction in the file for saving after the correction. FIG. 5 is a diagram showing an example of the file for saving after the correction including all of the information of the file for saving before the correction. In this way, if the information of the file for saving before the correction is included, the user of the file for saving can grasp the reviser from the re-acquired electronic certificate and the re-created electronic signature, and can grasp the timing of the revision from the re-acquired time stamp. Alternatively, the user of the file for saving can compare the files before and after the correction to grasp the different parts in the correction. The information processing apparatus 10 may correct the file for saving not only once but also multiple times. Note that the file of the online meeting is accessed by a plurality of users such as meeting participants. Therefore, an information processing apparatus 10 different from the information processing apparatus 10 that has saved the file for saving may revise the file for saving.

[0025] 3. Chat function The information processing device 10 may have other functions in addition to the functions described so far. For example, when the electronic data is data for an online conference, the information processing device 10 may have a function for participating in the online conference, etc., and a function for communicating with other information processing devices 10, such as a chat function. For example, the information processing device 10 may notify the information processing device 10 of another user who has access to the archive log file of a message urging approval of the archive log file using the chat function. In this case, the information processing device 10 that receives the message may operate as described above and output a file for storage including an electronic signature, etc. In this way, the information processing device 10 may instruct the other information processing device 10 to create a file for storage. Note that the information processing device 10 may create and output a file for storage in response to an instruction from a server that manages an online conference in which the user has participated. In other words, the information processing device 10 may create an output file in response to an instruction from another device. Alternatively, the information processing device 10 may have a function for acquiring an access right to participate in an online conference, etc., or an authentication function.

[0026] [Hardware configuration] The hardware configuration of the information processing device 10 will be described. Each component of the information processing device 10 may be configured with a hardware circuit. Alternatively, in the information processing device 10, each component may be configured using a plurality of devices connected via a network. For example, the information processing device 10 may be configured using cloud computing. Alternatively, in the information processing device 10, a plurality of components may be configured with a single piece of hardware. Alternatively, the information processing device 10 may be realized as a computer device including a central processing unit (CPU), a read only memory (ROM), a random access memory (RAM), and a network interface.

[0027] FIG. 6 is a block diagram showing an example of the hardware configuration of the information processing apparatus 10. The information processing apparatus 10 includes a CPU 610, a ROM 620, a RAM 630, a storage device 640, and a network interface 650.

[0028] The CPU 610 reads a program from at least one of the ROM 620 and the storage device 640. Then, based on the read program, the CPU 610 controls the RAM 630, the storage device 640, and the network interface 650. And the CPU 610 realizes functions as an electronic certificate acquisition unit 110, a signature file acquisition unit 120, an electronic signature creation unit 130, a time stamp acquisition unit 140, and a storage file output unit 150. In this way, the information processing apparatus 10 may realize functions as a combination of hardware and software. The CPU 610 may read a program included in a recording medium 690 storing a program in a computer-readable manner using a recording medium reading device (not shown). Alternatively, the CPU 610 may receive a program from an external device (not shown) via the network interface 650, store it in the RAM 630 or the storage device 640, and operate based on the stored program.

[0029] The ROM 620 stores the programs and fixed data executed by the CPU 610. The ROM 620 is, for example, a programmable ROM (P-ROM) or a flash ROM. The RAM 630 temporarily stores the programs and data executed by the CPU 610. The RAM 630 is, for example, a dynamic RAM (D-RAM). The storage device 640 stores the data and programs that the information processing apparatus 10 stores in the long term. The storage device 640 may store the secret key and the public key. Alternatively, the storage device 640 may store at least a part of the electronic certificate, the signature file, the electronic signature, the time stamp, and the storage file. The storage device 640 is, for example, a hard disk device, a solid state drive (SSD), or a disk array device.

[0030] The ROM 620 and the storage device 640 are non-transitory recording media. On the other hand, the RAM 630 is a transitory recording media. And the CPU 610 is operable based on the programs stored in the ROM 620, the storage device 640, and the RAM 630. That is, the CPU 610 is operable using either the non-transitory recording media or the transitory recording media. When realizing each function, the CPU 610 may use at least one of the RAM 630 and the storage device 640 as a temporary storage medium for programs and data.

[0031] The network interface 650 relays the data exchange with other devices (not shown) via the network. The network interface 650 realizes, for example, the communication functions with a CA, a TSA, etc. The network interface 650 is, for example, a local area network (LAN) card. Further, the network interface 650 may use wireless, not limited to wired.

[0032] [System] As an explanation of the information processing apparatus 10, an information processing system 20 which is an example of a system including the information processing apparatus 10 will be described. FIG. 7 is a block diagram showing an example of the information processing system 20 including the information processing apparatus 10. The information processing system 20 includes the information processing apparatus 10, a server 30, a CA 40, a TSA 50, a key server 60, and a network 70. The network 70 is a communication network that relays communication between devices. The information processing apparatus 10 acquires a secret key from the key server 60. The information processing apparatus 10 may acquire a public key from the key server 60. The information processing apparatus 10 acquires an electronic certificate from the CA 40. For example, the information processing apparatus 10 acquires an electronic certificate for the public key corresponding to the secret key used for creating an electronic signature from the CA 40. At that time, the CA 40 acquires a public key from the key server 60 or the information processing apparatus 10. The information processing apparatus 10 acquires a signature file from the server 30 and creates an electronic signature from the signature file using the secret key. The information processing apparatus 10 acquires a time stamp from the TSA. For example, the information processing apparatus 10 acquires a time stamp related to the signature file, the electronic signature, and the electronic certificate from the TSA. Then, the information processing apparatus 10 outputs a storage file including the signature file, the electronic signature, the electronic certificate, and the time stamp to the server 30.

[0033] Server 30 is, for example, a server that provides an online meeting service. Then, corresponding to the information processing apparatus 10, server 30 operates as follows, for example. Note that server 30 may execute authentication of information processing apparatus 10. When receiving a request for acquisition of a signature file from information processing apparatus 10, server 30 transmits the signature file to information processing apparatus 10. Server 30 may transmit a signature file to information processing apparatus 10 and instruct creation of a storage file. Then, when receiving a storage file from information processing apparatus 10, server 30 verifies the validity of the electronic signature, electronic certificate, and time stamp included in the storage file. In verifying the validity, server 30 appropriately uses CA 40, TSA 50, and key server 60. Then, when all of the electronic signature, electronic certificate, and time stamp are valid, server 30 stores the storage file. For example, server 30 stores the storage file in a storage device (not shown). Note that server 30 may be configured using the hardware shown in FIG. 6.

[0034] As described above, the present invention has been described with reference to the embodiments, but the present invention is not limited to the above embodiments. Various changes that can be understood by those skilled in the art can be made to the configuration and details of the present invention within the scope of the present invention.

Industrial Applicability

[0035] The present invention can be used in a system that provides functions of meetings, consultations, and calls.

Explanation of Signs

[0036] 10 Information processing apparatus 20 Information processing system 30 Server 40 CA 50 TSA 60 Key server 70 Network 110 Electronic certificate acquisition unit 120 Signature file acquisition unit 130 Electronic signature creation unit 140 Timestamp acquisition unit 150 Output unit for file to be saved 600 Computer device 610 CPU 620 ROM 630 RAM 640 Storage device 650 Network interface 690 Recording medium

Claims

1. An electronic certificate acquisition means for acquiring an electronic certificate, A signature file acquisition means for acquiring a signature file, An electronic signature creation means for creating an electronic signature by encrypting a hash value calculated from the signature file using a private key corresponding to the public key used for issuing the electronic certificate, A time stamp acquisition means for acquiring a time stamp related to the signature file, the electronic signature, and the electronic certificate, A storage file output means for outputting a storage file including the signature file, the electronic signature, the electronic certificate, and the time stamp, including, The signature file acquisition means acquires the storage file, After correcting the signature file included in the acquired storage file, the electronic certificate acquisition means re-acquires the electronic certificate, The electronic signature creation means re-creates the electronic signature by encrypting a hash value calculated from the corrected signature file using a private key corresponding to the public key used for issuing the re-acquired electronic certificate, The time stamp acquisition means re-acquires the time stamp related to the corrected signature file, the re-created electronic signature, and the re-acquired electronic certificate, The storage file output means outputs the storage file including the signature file before correction, the electronic signature before re-acquisition, the electronic certificate before regeneration, and the time stamp before re-acquisition, and the signature file after correction, the re-created electronic signature, the re-acquired electronic certificate, and the re-acquired time stamp An information processing apparatus.

2. The signature file is an archive log file including audio in an online call or an archive log file including audio and video in an online meeting The information processing apparatus according to claim 1.

3. The file output means for storage outputs, as the file for storage, a file that can integrally process the file for signature, the electronic signature, the electronic certificate, and the time stamp. The information processing apparatus according to claim 1 or 2.

4. An information processing apparatus according to claim 1 or 2, and when receiving a request for the signature file from the information processing apparatus, transmits the signature file to the information processing apparatus, when receiving the storage file from the information processing apparatus, verifies the validity of the electronic signature, the electronic certificate, and the time stamp included in the storage file, and stores the storage file when all of the electronic signature, the electronic certificate, and the time stamp are valid. a server An information processing system including the same.

5. The information processing apparatus creates and outputs the storage file upon receiving an instruction from another information processing apparatus or a server. The information processing system according to claim 4.

6. obtains an electronic certificate, obtains a signature file, creates an electronic signature by encrypting a hash value calculated from the signature file using a private key corresponding to a public key used for issuing the electronic certificate, obtains a time stamp related to the signature file, the electronic signature, and the electronic certificate, outputs a storage file including the signature file, the electronic signature, the electronic certificate, and the time stamp, obtains the storage file, after modifying the signature file included in the obtained storage file, re-obtains the electronic certificate, Using the private key corresponding to the public key used for issuing the re-acquired electronic certificate, encrypt the hash value calculated from the modified signature file to recreate the electronic signature. Re-acquire the modified signature file, the recreated electronic signature, and the time stamp related to the re-acquired electronic certificate. Output the storage file including the signature file before modification, the electronic signature before re-acquisition, the electronic certificate before regeneration, and the time stamp before re-acquisition, and the signature file after modification, the recreated electronic signature, the re-acquired electronic certificate, and the re-acquired time stamp. Information processing method.

7. A process of acquiring an electronic certificate, A process of acquiring a signature file, A process of creating an electronic signature by encrypting the hash value calculated from the signature file using the private key corresponding to the public key used for issuing the electronic certificate. A process of acquiring the signature file, the electronic signature, and the time stamp related to the electronic certificate. A process of outputting a storage file including the signature file, the electronic signature, the electronic certificate, and the time stamp. A process of acquiring the storage file. After modifying the signature file included in the acquired storage file, a process of re-acquiring the electronic certificate. A process of recreating the electronic signature by encrypting the hash value calculated from the modified signature file using the private key corresponding to the public key used for issuing the re-acquired electronic certificate. A process of re-acquiring the modified signature file, the recreated electronic signature, and the time stamp related to the re-acquired electronic certificate. A process of outputting the file for storage including the signature file before correction, the electronic signature before re-acquisition, the electronic certificate before regeneration, and the timestamp before re-acquisition, and the signature file after correction, the re-created electronic signature, the re-acquired electronic certificate, and the re-acquired timestamp A program that causes a computer to execute.

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