WO2003073399A1

WO2003073399A1 - Method and system for verifying data originality

Info

Publication number: WO2003073399A1
Application number: PCT/JP2002/001743
Authority: WO
Inventors: Ikuo Makita; Toshihisa Ishikawa
Original assignee: Fujitsu Limited
Priority date: 2002-02-26
Filing date: 2002-02-26
Publication date: 2003-09-04

Abstract

In order to verify the originality of document data even when the format is converted to enable confidential communication between areas where different code formats are used, a second Hash value is calculated from second data which is generated by performing format conversion to first data, relates the Hash value to an electronic certificate issuance number, and stores them in a table. Only the second data is transmitted to a reception side and verified.

Description

Description Original data verification method and system [Technical field]

The present invention relates to data communication technology, and more particularly, to data originality verification technology.

[Background technology]

In electronic commerce, a predetermined hash algorithm is applied to the document data so as to prevent falsification of the document data, such as a contract with which the transaction is made, and the generated hash value is encrypted to generate an electronic signature. Then, the electronic signature is transmitted to the trading partner together with the encrypted document data. The trading partner decrypts the document data and applies a predetermined hash algorithm to generate a hash value. In addition, by decrypting the electronic signature, restoring the hash value, and comparing it with the generated hash value, it can be confirmed that the electronic signature has not been tampered with. If such technology is used, transactions between two companies can be processed without problems.

However, in the international trade business, many companies and various administrative organizations are involved. The technology described above may be applied to such communication between two companies or administrative organizations.However, when document data involving three or more companies or administrative organizations is communicated, Is not always enough with the techniques described above. For example, when document data is transmitted from A to C via B, there is a case where the document data generated in A cannot be processed in the format as it is due to the system and legal system of C. In this case, B may perform format conversion on the document data in accordance with the system and legal system of C. However, if such a format conversion is performed, confirmation of A as the transmission source cannot be obtained.

[Disclosure of the Invention] Accordingly, it is an object of the present invention to provide a technique for obtaining confirmation of a transmission source even when document data is changed halfway. In order to achieve the above object, an information processing method according to the first aspect of the present invention and implemented by, for example, an RSP server of a domestic RSP (Repository Service Provider) center includes a first computer (for example, a computer of an export company) Performing a format conversion corresponding to a destination of the first data (for example, an importing company) on the first data (for example, data of an invoice) received from the first data to generate second data And the hash value of the second data is calculated, and the hash value is associated with the information on the electronic certificate related to the first computer and stored in a storage device (for example, a hash, an electronic certificate issue number index table). And transmitting the second data to a second computer associated with the destination (for example, an RSP server at an overseas RSP center). Reading the information about the digital certificate corresponding to the received hash value from the storage device when the hash value is received from the second computer; and reading the information about the read digital certificate from the second computer. Transmitting to a computer.

In the communication between the RSP server of the domestic RSP center that implements the above information processing method and the first computer of the exporting company, no tampering has occurred using the digital certificate related to the first computer of the exporting company If this is confirmed, the first data in the domestic RSP server is genuine data. Here, the digital certificate corresponding to the first data is a digital certificate related to the first computer of the export company. Also, the relationship between the first data and the second data that is format-converted from the first data is unique. Furthermore, the correspondence between the second data and the hash value generated by using a predetermined hash function from the second data is also unique. In other words, the digital certificate corresponding to the hash value is also the digital certificate associated with the export company's first computer. Therefore, if the computer of the importing company receives the second data and generates a hash value from the second data using the same hash function, the RSP server at the domestic RSP center will respond to the hash value. The information on the digital certificate obtained is considered to be an export company that is held in advance by the import company, etc. It should be the same as the information about the person's digital certificate. If it is the same, there is no problem if the importing company etc. processes the data using the second data as the data from the specified exporting company. If they are not the same, the exporter corresponding to the second data cannot be properly identified, and it can be recognized that tampering or other problems have occurred. Note that, in the first aspect of the present invention, when information about the digital certificate corresponding to the received hash value cannot be obtained from the storage device, the configuration further includes a step of generating information for warning. There may be. This is because some problem has occurred and it is necessary to notify the operator or the first or second or first and second computers.

The information on the digital certificate described above may be identification information (for example, a serial number) of the digital certificate. With this information, there is no duplication if there is only one digital certificate issuer. According to the second aspect of the present invention, for example, an information processing method implemented by a computer of an importing company or the like calculates a hash value for data received from another computer (for example, an RSP server of an overseas RSP center). Transmitting the hash value to another computer; and receiving information about the digital certificate corresponding to the hash value from the other computer, when the information is received from the other computer. Storing information about the received digital certificate in a storage device, and comparing the received information about the digital certificate with the information about the digital certificate of the data generator (eg, an export company).

In this way, for example, in a computer of an importing company or the like, the received data is not the same as the data generated by the source of the data, as well as the fact that the computer has not been tampered with another computer. In both cases, it is possible to verify that the data is generated by the source of the received data.

Note that, in the second aspect of the present invention, when the information on the received electronic certificate and the information on the electronic certificate from which the data is generated do not match, the step of generating information for warning is performed. In some cases, it further includes. This is because data received from another computer cannot be used as it is. Further, in the comparison step described above, information on the electronic certificate of the generator of the data is obtained by using information of the generator identified from the data and information on the electronic certificate prepared in advance. It may be configured to include a step of searching and acquiring a correspondence table with the certificate owner.

Note that the information on the digital certificate described above may be identification information (for example, a serial number) of the digital certificate.

Note that it is also possible to create a program for causing a computer to execute the information processing methods according to the first and second aspects of the present invention. The program may be, for example, a floppy disk, CD-ROM, optical disk, or the like. It is stored in a storage medium or storage device such as a magnetic disk, a semiconductor memory, and a hard disk. It may also be distributed via networks such as the Internet. The data being processed is temporarily stored in the computer memory.

[Brief description of drawings]

FIG. 1 is a diagram showing an outline of a system according to an embodiment of the present invention.

FIG. 2 is a diagram showing an example of data stored in a format conversion program storage unit.

FIG. 3 is a diagram showing an example of a hash / electronic certificate issue number index table. FIG. 4 is a diagram showing an example of a digital certificate list table.

FIG. 5 is a diagram showing an electronic signature and an encryption method.

FIG. 6 is a diagram showing a first part of a processing flow according to one embodiment of the present invention. In Fig. 7, (A) is a schematic diagram of the main data transmitted from the exporting company A server to the RSP server of the domestic RSP center B, and (B) is a schematic diagram of the main data transmitted from the RSP server of the domestic RSP center B to the overseas. It is a schematic diagram of the main data transmitted to the RSP server of the RSP center C, and (C) is a schematic diagram of the main data transmitted from the RSP server of the overseas RSP center C to the importing company D server. (D) is a schematic diagram of the main data transmitted from the importing company D server to the RSP server 9 of the overseas RSP center C,

(E) is a schematic diagram of the main data sent from the RSP server of the overseas RSP center C to the RSP server of the domestic RSP center B, and (F) is the R diagram of the domestic RSP center B. It is a schematic diagram of the main data transmitted from the SP server to the RSP server of the overseas RSP center C. (G) is a schematic diagram of the main data transmitted from the RSP server of the overseas RSP center C to the importing company D server. It is.

FIG. 8 is a diagram showing a second part of the processing port according to one embodiment of the present invention. FIG. 9 is a diagram showing a third part of the processing flow according to one embodiment of the present invention. FIG. 10 is a diagram showing a fourth part of the processing flow according to the embodiment of the present invention.

[Best mode for carrying out the present invention]

FIG. 1 shows a schematic diagram of a system according to an embodiment of the present invention. This embodiment is an example in which the present invention is applied to a trade EDI (Electric Data Interchange) system. Here, it is necessary to transmit the document data from Company A to Company D.For example, the document data according to the laws and regulations of the country to which Company A belongs is converted into the document data according to the laws and regulations of the country to which Company D belongs. Suppose you have to.

For example, on the Internet 1 that is a computer network, there are two export companies A and 3 that are managed and operated by the export company A, which is the source of document data such as invoices, and companies in the same country as the export company A. RSP server 7 at RSP center B in Japan to provide services for, and provide, for example, document data format conversion and document data storage services, and services to companies in the same country as importing company D. RSP server 9 at an overseas RSP center C for implementing the application and providing, for example, document data storage services, and an import company D server 5 managed and operated by, for example, the import company D to which the document data is sent. And are connected. Many corporate servers are connected to the Internet1 instead of two. In addition, there may be more than one RSP server, not just one in each country.

In some cases, the relationship between export and import is reversed. Export company A is also the destination of document data for import, and import company B is also the source of document data for export. In that case, the RSP server 9 of the overseas RSP center C performs the format conversion of the document data and the storage service of the document data, and the RSP server 7 of the domestic RSP center B does not perform the format conversion of the document data. Implement data storage services. Document data storage services include, for example, Includes services for recording the transfer of rights. The importing company D server 5 may be managed and operated not only by the importing company but also by, for example, overseas customs.

The export company A server 3 is connected to one or more user terminals 3b via, for example, a LAN (Local Area Network) 3a. It should be noted that the configuration may be such that the communication is performed via another network such as the Internet instead of the LAN. The employee of the exporting company A operates the user terminal 3b to instruct the exporting company A server 3 to transmit document data and the like. Similarly, the importing company D server 5 is connected to one or more user terminals 5b via, for example, a LAN 5a. It should be noted that the configuration may be such that the communication is performed via another network such as the Internet instead of the LAN. The employee of the importing company D operates the user terminal 5b to instruct the importing company D server 5 to receive document data and the like. Note that the export company A server 3 or the import company D server 5 and the user terminal may be encrypted using SSL (Secure Socket Layer Protocol). In the present embodiment, the description of the processing by the user terminal is omitted.

The RSP server 7 of the domestic RSP center B stores a format conversion program storage unit 71 that stores a format conversion program for converting the format of document data according to the destination based on the request from the source. Correspondence between the document data storage unit 75 for storing document data, etc., and the hash value of the format-converted document data and the identification information (eg, issue number (serial number)) of the sender's digital certificate The digital certificate issue number index table storage unit 73 is managed. Although not shown, the information of the electronic certificates of the related companies and organizations is stored in the storage device.

The RSP server 9 of the overseas RSP center C receives a format conversion program storage unit 91 that stores a format conversion program for converting the format of document data and the like according to the destination based on a request from the source. Correspondence relationship between the document data storage unit 95 for storing document data, etc., and the hash value of the format-converted document data and the identification information (eg, issue number (serial number)) of the sender's digital certificate The digital certificate issuance number index table storage unit 93 is managed. However, in the following description, only the case where the RSP server 9 of the overseas RSP center C does not perform format conversion will be described. The program storage section 91 and the hash · digital certificate issue number index table storage section 93 are not used.

The export company A server 3 manages an electronic certificate data storage unit 31 for storing electronic certificate data of each company or the RSP center. The importing company D server 5 also manages an electronic certificate data storage unit 51 that stores the electronic certificate data of each company or the RSP center. Next, FIG. 2 shows an example of data stored in the format conversion program storage section 71 or 91 of the RSP server 7 of the domestic RSP center B or the RSP server 9 of the overseas RSP center C. In the example of FIG. 2, a column 201 of the destination country name and a column 203 of the name of the format conversion program are provided. For example, if the destination country is American, use a format conversion program named USA.eXe. If the destination country is a book, use a format conversion program called JPN.eXe. If the destination country is the United Kingdom, use a format conversion program called U K. eX e.

Fig. 3 shows an example of a table stored in the hash table of the RSP server 7 of the domestic RSP center B or the RSP server 9 of the overseas RSP center C . In the example of FIG. 3, a column 211 of a hash value calculated from the document data after format conversion and a column 211 of a corresponding digital certificate issue number are included. For example, when specific document data is sent from the export company A server 3, the hash of the specific document data after format conversion corresponding to the destination and the digital certificate used by the export company Α server 3 The issue number of the certificate is recorded correspondingly.

FIG. 4 shows an example of a digital certificate list table stored in the digital certificate data storage unit 31 or 51 of the export company A server 3 or the import company D server 5. In FIG. 4, a column 222 of the digital certificate issue number and a column 222 of the owner information of the digital certificate are included. The exporting company A server 3 or the importing company D server 5 obtains the digital certificate of each related company or institution in advance or immediately before processing, and stores it in the digital certificate data storage unit 31 or 51. The process flow of the system shown in FIG. 1 will be described below. Before that, the process of transmitting data after encryption between two computers will be described with reference to FIG. When transmitting the original plaintext data 311 from the source computer 301 to the destination computer 303 after encrypting it, the source computer 301 sends one-time data to the original plaintext data 3111. The data encryption process 3 2 3 is performed using the common key 3 2 5 to generate encrypted data 3 4 5. For example, triple DES (Data Encryption Standard) is used for the data encryption process 232. Also, for example, a hash algorithm 313 using a hash function SHA-1 is applied to the original plaintext data 311 to generate an original hash value 319. Then, for example, an RSA encryption process 3 21 is performed on the original hash value 3 19 using the source secret 3 11 to generate a digital signature 3 41. Also, for example, RSA encryption processing 3 27 is performed on the one-time common key 3 2 5 using the transmission destination public key 3 31 obtained from the transmission destination public key certificate 3 29, Generate an encrypted one-time common key 347. The digital signature 3 4 1 thus generated, the encrypted data 3 4 5 and the encrypted one-time common key 3 4 7 together with the sender's public key certificate 3 15 together with the HTTP (Hyper Text Transfer Protocol) ) And send it to the destination computer 303.

Upon receiving the electronic signature 3 41 and the sender's public key certificate 3 15, the destination computer 303 extracts the sender's public key 3 55 from the sender's public key certificate 3 15. The RSA decryption processing 35 1 is performed on the electronic signature 3 41 to generate a hash value 3 53 of the original signature. Also, upon receiving the encrypted data 345 and the encrypted one-time common key 347, the private key 363 of the transmission destination is transmitted to the one-time common key 347, which has been encrypted. The RSA decryption process 359 is performed by using this, and the one-time common key 361 is restored. Using this one-time common key 361, the data decryption processing 357 is performed on the 喑 -code highlighter 345 to generate the received plaintext data 366. The destination computer 303 holds the public key certificate 329 of the destination, which is transmitted to the source as needed. The received plaintext data 36 7 contains the same hash algorithm 36 6 Applying 9 produces a hash value of 3 7 1 By comparing the original hash value 353 with the hash value 371, it is possible to confirm whether or not the received plaintext data has been altered from the original plaintext 311. That is, if the original hash value 3 5 3 and the hash value 3 7 1 match, the data is data transmitted from the owner of the public key certificate 3 29, and the data has not been tampered with. It can be determined that there is no such information. If tampering has not been performed, the received plaintext data can be used for subsequent processing. Assuming the above processing, the processing of this embodiment will be described with reference to FIG. The export company A server 3 or its user terminal 3b generates document data to be transmitted to the import company D (step S1). When the user terminal 3b generates the document data, the document data is transmitted from the user terminal 3b to the export company A server 3. Exporting company A server 3 encrypts the generated document data with a one-time common key, calculates a hash value from the document data using a predetermined hash function (for example, MD5), and calculates the hash value. The digital signature of the export company A is generated by performing the 喑 sign with the secret key of the export company A and stored in the storage device (step S3). In addition, the one-time common key is also encrypted with the public key of the domestic RSP center B and stored in the storage device. Then, the export company A server 3 designates the import company D as a destination, and sends the encrypted document data and the electronic signature of the export company A to the RSP server 7 of the domestic RSP center B (step S). Five ) . At this time, the encrypted one-time common key and the export company A's digital certificate are also sent. Note that electronic certificates may not have been sent at this stage, but may have been sent before this stage.

The data transmitted from the exporting company A server 3 to the RSP server 7 at the domestic RSP center B mainly consists of encrypted document data 401 and export, as shown in Fig. 7 (A). The electronic signature of Company A is 402. The RSP server 7 of the domestic RSP center B sends the information of the importing company D as the designation of the destination from the exporting company A server 3, The signature, the encrypted one-time common key, and the digital certificate of the export company A are received and temporarily stored in the storage device (step S7). Then, the encrypted one-time common key is decrypted with the secret key of RSP Center B in Japan, and the decrypted document data is decrypted using the decrypted one-time common key, and the document data is stored. Store in part 75. In addition, the electronic signature of the export company A is verified (step S9). That is, a hash value is calculated from the decrypted document data using a predetermined hash function and stored in the storage device. On the other hand, the hash value is extracted by decrypting the digital signature of the export company A with the export company A's public key, and stored in the storage device. Then, it is determined whether these hash values match. If there is a discrepancy, there is a possibility that the export company A server 3 has been tampered with in the course of communication with the RSP server の of the domestic RSP center B, so warning information about tampering is generated. Then, the warning information is output to, for example, the administrator of the RSP server 7 (step S11).

On the other hand, if the hash values match, it means that the authentic document data has been received from the exporting company A server 3, and the following processing can be performed. That is, the RSP server 7 reads the format conversion program adapted to the importing company D as the transmission destination from the format conversion program storage unit 71, and performs the format conversion process on the document data decrypted by the format conversion program. Then, the result is stored in the storage device or the document data storage unit 75 (step S13). In addition, a hash value is calculated by a predetermined hash function from the format-converted document data and stored in the storage device (step S15). Then, a pair of the hash value of the document data after the format conversion and the issue number (serial number) of the digital certificate of the export company A is hashed. ■ Hash of the digital certificate issue number index table storage unit 73. Register in the number index table (step S17). By registering in the hash 'digital certificate issue number index table, it will be possible to confirm later that importing company D really received the document data from exporting company A.

The RSP server 7 generates a digital signature of the domestic RSP center B by converting the hash of the converted document data with the secret key of the domestic RSP center B to generate the digital signature of the domestic RSP center B. With a one-time common key (Step SI 9). The one-time common key is also encrypted with the public key of the overseas RSP center C for the importing company D as the transmission destination. Then, the import company D is specified as the destination, and the encrypted document data after the format conversion and the electronic signature of the domestic RSP center B are sent to the overseas RSP center C for the import company D as the destination. The data is transmitted to the P server 9 (step S21). At this time, the encrypted one-time common key and the digital certificate of the domestic RSP center B are also transmitted. Note that digital certificates may not have been sent at this stage but may have been sent before this stage.

As shown in Fig. 7 (B), the data transmitted from the RSP server 7 of the domestic RSP center B to the RSP server 9 of the overseas RSP center C is mainly composed of encrypted document data 411 after format conversion. This is the electronic signature 412 of RSP Center B in Japan. The processing shifts from FIG. 6 to FIG. The RSP server 9 of the overseas RSP center C sends the information of the importing company D as the destination designation, the encrypted document data after format conversion, and the RSP server B of the domestic RSP center B from the RSP server 7 of the domestic RSP center B. The digital signature, the encrypted one-time common key, and the digital certificate of the domestic RSP center B are received and temporarily stored in the storage device (step S23). Then, the encrypted one-time common key is decrypted with the secret key of the overseas RSP center C, and the encrypted one-time common key is used to decrypt the encrypted document data after the format conversion. Store in storage unit 95. In addition, verification processing of the electronic signature of the domestic RSP center B is performed (step S25). That is, a hash value is calculated by a predetermined hash function from the document data after the format conversion and stored in the storage device. On the other hand, the hash value is extracted by decrypting the digital signature of the domestic RSP center B with the public key of the domestic RSP center B, and stored in the storage device. Then, it is determined whether or not these hash values match. If they do not match, there is a possibility that tampering has been performed in the course of communication from the RSP server 7 of the domestic RSP center B to the RSP server 9 of the overseas RSP center C, and the warning information Is generated, and the warning information is output to, for example, the administrator of the RSP server 9 (step S27). No format conversion is required for the RSP server 9 of the overseas RSP center C. In the present embodiment, only relay is performed, but processing such as storing the document data after format conversion in the document data storage unit 95 is performed. Here, the document data after the format conversion is encrypted with the one-time common key and stored in the storage device. In addition, a hash value of the document data after format conversion is generated using a predetermined hash function, and the hash value is encrypted with a secret key, thereby generating an electronic signature of the overseas RSP center C and storing it in the storage device. (Step S29). The one-time encryption key is also encrypted with the public key of importing company D, which is the destination. Then, the RSP server 9 transmits the encrypted document data after the format conversion and the electronic signature of the overseas RSP center C to the server 5 of the import company D, which is the transmission destination (step S31). At this time, the encrypted one-time common key and the digital certificate of the overseas RSP center C are also transmitted. Note that electronic certificates may not have been sent at this stage but may have been sent before this stage.

As shown in Fig. 7 (C), the data transmitted from the RSP server 9 of the overseas RSP center C to the importing company D server 5 mainly includes encrypted document data 421 after format conversion, as shown in Fig. 7 (C). The electronic signature of the overseas RSP center C is 422. The importing company D server 5 sends the encrypted document data after format conversion, the electronic signature of the overseas RSP center C, the encrypted one-time common key, and the overseas RSP center C from the server 9 of the overseas RSP center C. The electronic certificate is received and temporarily stored in the storage device (step S33). Then, the decrypted one-time common key is decrypted with the secret key of the importing company D, and the format-converted encrypted document data is decrypted and decrypted using the decrypted one-time common key. It is stored in the device (step S35). Also, a hash value is calculated from the format-converted document data using a predetermined hash function and stored in a storage device (step S37). On the other hand, the hash value is extracted by decrypting the digital signature of the overseas RSP center C with the public key of the overseas RSP center C and stored in the storage device. Then, the digital signature is verified by judging the power that these hash values match (step S39). If they do not match, the RSP server 9 of the overseas RSP center C and the importing company D server 5 Since there is a possibility that tampering has been performed in the course of communication, warning information is generated, and the warning information is output to, for example, the administrator of the importing company D server 5 (step S41). On the other hand, if the two hash values match, it means that the authentic document data after format conversion has been received from the overseas RSP center C. However, importing company D does not know whether or not the converted document data is actually generated from the document data generated by exporting company A. This is because format conversion is performed by the RSP server 7 of the domestic RSP center B. Therefore, the importing company D server 5 encrypts the hash value generated in step S37 with the one-time common key and stores it in the storage device (step S43). The one-time common key is also encrypted using the public key of the overseas RSP center C. Further, another hash value is calculated from the hash value generated in step S37 with a predetermined hash function, and the digital signature of the import company D is generated by encrypting the hash value with the secret key of the import company D, and is stored in the storage device. It is stored (step S45). Then, the RSP server 7 of the domestic RSP center B serving the export company A is designated as the destination, and the identification code of this processing, the encrypted hash value, and the electronic signature of the import company D are obtained. The data is transmitted to the RSP server 9 of the overseas RSP center C (step S47). The one-time common key and the digital certificate of importing company D are also sent. Note that electronic certificates may not have been sent at this stage but may have been sent before this stage. In addition, it does not specify the RSP server 7 of the domestic RSP center B as the destination, but outputs a verification request including information on the exporting company A or the company of the country of the exporting company A. Alternatively, the configuration may be such that the RSP server 7 of the domestic RSP center B is specified.

The data transmitted from the importing company D server 5 to the RSP server 9 of the overseas RSP center C mainly consists of the encrypted hash value of the document data after format conversion, as shown in Fig. 7 (D). The digital signature of importing company D is 432.

The RSP server 9 of the overseas RSP center C receives the information of the RSP server 7 of the domestic RSP center B, which is the transmission destination, the identification code of this processing, the encrypted hash value, The digital signature of the importing company D, the encrypted one-time common key, and the electronic certificate of the importing company D are received and temporarily stored in a storage device. Step S49). Here, the pair of the importing company D server 5 and the identification code is recorded. When the information of the export company A or the company of the country of the export company A is received as the verification request instead of the information of the RSP server 7 of the domestic RSP center B, the RSP server 7 of the domestic RSP center B is specified. Perform processing. Subsequent processing is shown in FIG. Shifting to Fig. 9, the RSP server 9 decrypts the encrypted one-time common key with the secret key of the overseas RS Ρ center C, and encrypts using the decrypted one-time common key. The hash value is decrypted and stored in the storage device. In addition, the digital signature of the importing company D is verified (step S51). That is, another hash value is calculated from the decrypted hash value by a predetermined hash function and stored in the storage device. On the other hand, the electronic signature of the importing company D is decrypted with the public key of the importing company D to extract the novache value and store it in the storage device. Then, it is determined whether these hash values match. If they do not match, there is a possibility that the import company D server 5 has been tampered with in the course of communication between the overseas RSP center C and the RS 9 server 9, so that warning information is generated. The warning information is output to the administrator of the RSP server 9 or the like (step S53). The warning information may be transmitted to the importing company D server 5 together with the identification code to notify the manager of the importing company D of the warning information.

Next, the RS @ server 9 performs a decryption on the decrypted hash value with the one-time common key, and stores the hash value in the storage device. Also, another hash value is generated from the decrypted hash value using a predetermined hash function, and the other hash value is encrypted with the secret key of the overseas RS Ρ center C, thereby obtaining the overseas RS Ρ center. A digital signature of C is generated and stored in the storage device (step S55). In addition, the one-time encryption key is also encrypted with the public key of the destination RS {Center} in Japan. Then, the RSP server 9 sends the identification code of this process, the hash value of the document data after format conversion, and the digital signature of the overseas RS center C to the domestic RS center that is the transmission destination. It is sent to RS @ server 7 (step S57). At this time, the encrypted one-time common key and the digital certificate of the overseas RS @ Center C are also sent. Note that electronic certificates may not have been sent at this stage, but may have been sent before this stage. The data transmitted from the RSP server 9 of the overseas RSP center C to the RSP server 7 of the domestic RSP center B mainly encrypts the document data after format conversion as shown in Fig. 7 (E). a hash value ⁴ 41, an electronic signature 44 2 overseas RSP center C.

The RSP server 7 of the domestic RSP center B is converted into the RSP server 9 of the overseas RSP center C, the hash value with the identification code, the digital signature of the overseas RSP center C, and the identification code. The one-time common key and the electronic certificate of the overseas RSP center C are received and temporarily stored in the It device (step S59). The RSP server 7 decrypts the encrypted one-time common key with the secret key of the domestic RSP center B, decrypts the encrypted hash value using the decrypted one-time common key, and stores it in the storage device. Store. In addition, the digital signature of the overseas RSP center C is verified (step S61). That is, another hash value is calculated from the decrypted hash value using a predetermined hash function, and stored in the storage device. On the other hand, the hash value is extracted by decrypting the electronic signature of the overseas RSP center C with the public key of the overseas RSP center C and stored in the storage device. Then, it is determined whether these hash values match. If they do not match, it is possible that tampering has been performed in the course of communication from the RSP server 9 at the overseas RSP center C to the RSP server 7 at the domestic RSP center B. Then, the information of the warning is output to, for example, the administrator of the RSP server 7 (step S63). The warning information may be sent together with the identification code to the RSP server 9 of the overseas RSP center C to notify the administrator of the overseas RSP center C or the like. Further, the configuration may be such that the information is transmitted from the RSP server 9 of the overseas RSP center C to the importing company D server 5 together with the identification code, and the manager of the importing company D is notified. .

Next, the RSP server 7 searches the hash / electronic certificate issue number index table with the decrypted hash value, and confirms that the electronic certificate issue number has been obtained (step S65). If the digital certificate issue number cannot be obtained from the hash 'electronic certificate issue number index table, there is a possibility that tampering has been performed or an inappropriate format conversion has been performed on any of the existing routes. Generates warning information and outputs the warning information to, for example, the administrator of the RSP server 7. Yes (step S67). The warning information may be transmitted to the RSP server 9 of the overseas RSP center C together with the identification code to notify the administrator of the overseas RSP center C or the like. Further, the configuration may be such that the information is transmitted from the RSP server 9 of the overseas RSP center C to the importing company D server 5 together with the identification code, and the manager of the importing company D is notified.

If any digital certificate issue number can be obtained from the hash 'electronic certificate issue number index table, the issue number of the digital certificate is encrypted with a one-time common key and stored in the storage device. In addition, a hash value is generated from the issue number of the digital certificate using a predetermined hash function, and the hash value is encrypted with the secret key of the domestic RSP center B to generate an electronic signature of the domestic RSP center B. Then, it is stored in the storage device (step S69). The one-time password is also encrypted with the public key of the overseas RSP center C that is the destination. Then, the RSP server 7 sends the identification code of this processing, the encrypted digital certificate issue number, and the electronic signature of the domestic RSP center B to the RSP server 9 of the overseas RSP center C of the transmission source. (Step S71). At this time, the encrypted one-time common key and the digital certificate of RSP center B in Japan are also sent. Note that digital certificates may not have been sent at this stage but may have been sent before this stage.

The data transmitted from the RSP server 7 of the domestic RSP center B to the RSP server 9 of the overseas RSP center C mainly consists of the encrypted electronic certificate issue number 45 as shown in Fig. 7 (F). 1 and digital signature 452 of RSP center B in Japan.

The RSP server 9 of the overseas RSP center C receives the identification code, the encrypted digital certificate issue number, the electronic signature of the domestic RSP center B, and the 喑 number from the RSP server 7 of the domestic RSP center B. The one-time common key and the digital certificate of the domestic RSP center B are received and stored in the storage device (step S73). Subsequent processing continues to Figure 10. Moving to Fig. 10, the RSP server 9 decrypts the decrypted one-time common key with the secret key of the overseas RSP center C, and encrypts using the decrypted one-time common key. Decrypts the digital certificate issue number and stores it in the storage device. Also, domestic RSP The verification processing of the digital signature of the center B is performed (step S75). That is, a hash value is calculated from the decrypted digital certificate issue number using a predetermined hash function, and stored in the storage device. On the other hand, the hash value is extracted by decrypting the digital signature of domestic RSP center B with the public key of domestic RSP center B, and stored in the storage device. Then, it is determined whether these hash values match. If they do not match, there is a possibility that tampering has been performed in the course of communication from the RSP server 7 of the domestic RSP center B to the RSP server 9 of the overseas RSP center C. Is generated, and the warning information is output to, for example, the administrator of the RSP server 9 (step S77). The warning information may be transmitted to the importing company D server 5 together with the identification code to notify the manager of the importing company D of the warning information. Further, the identification code and the warning information may be transmitted to the RSP server 7 of the domestic RSP center B.

If there is no tampering, the RSP server 9 then encrypts the digital certificate and the line number with the one-time common key, and stores it in the storage device. In addition, a hash value is generated from the digital certificate issue number using a predetermined hash function, and the hash value is encrypted with the secret key of the overseas RSP center C to generate an electronic signature of the overseas RSP center C. And stores it in the storage device (step S79). The one-time encryption key is also encrypted with the public key of importing company D, which is the destination. Then, the RSP server 9 transmits the identification code of this processing, the encryption digital certificate issue number, and the electronic signature of the overseas RSP center C to the importing company D server 5 stored corresponding to the identification code. (Step S81). At this time, the encrypted one-time common key and the electronic certificate of the overseas RSP center C are also transmitted. Note that electronic certificates may not have been sent at this stage but may have been sent before this stage.

The data transmitted from the RSP server 9 of the overseas RSP center C to the importing company D server 5 mainly consists of the encrypted digital certificate issue number 461 and the overseas RSP server as shown in Fig. 7 (G). The electronic signature 462 of the center C.

The importing company D server 5 sends the identification code, the encryption digital certificate issue number, the electronic signature of the overseas RSP center C, and the encrypted one-time common key from the RSP server 9 of the overseas RSP center C. Then, the digital certificate of the overseas RSP center C is received and temporarily stored in the storage device (step S83). And the encrypted one-time common key Is decrypted with the private key of the importing company D, the decrypted one-time common key is used, the decrypted digital certificate issue number is decrypted, and stored in the storage device. In addition, the digital signature of the overseas RSP center C is verified (step S85). That is, a hash value is calculated by a predetermined hash function from the decrypted digital certificate issue number, and stored in the storage device. On the other hand, the hash value is extracted by decrypting the digital signature of the overseas RSP center C with the public key of the overseas RSP center C and stored in the storage device. Then, these hash values are judged to have the same power. If there is a discrepancy, there is a possibility that tampering has been performed during the communication process of the importing company D server 5 from the RSP server 9 of the overseas RSP center C, and warning information is generated. The warning information is output to the administrator of the D server 5 (step S87).

If the hash values match, there is no particular problem in the communication between the RSP server 9 of the overseas RSP center C and the importing company D server 5, and the following processing is performed. The import company D server 5 specifies the document data to be processed from the received identification code, and further specifies the identification information of the export company from the document data. Then, the electronic certificate list table is searched using the identification information of the export company, and the corresponding electronic certificate issue number is obtained. The importing company D server 5 compares the received and decrypted electronic certificate issue number with the electronic certificate issue number obtained from the electronic certificate list table (step S89).

If the digital certificate issuance numbers do not match, tampering has occurred in the communication path, the electronic signature of the exporting company A is not used, or the format conversion in the RSP server 7 of the domestic RSP center B has failed. Since the problem was found to be appropriate, the format-converted document data decrypted in step S35 (Fig. 8) is not based on the data generated by export company A. Is determined. Therefore, since the document data cannot be used as genuine data, for example, warning information indicating that the document data cannot be verified as data based on the export company A is generated, and the administrator of the import company A, etc. The warning information is output to the user (step S93). Warning information may be notified to overseas RSP center C or domestic RSP center B. On the other hand, if the two digital certificate issue numbers match, it means that the document data after the format conversion decrypted in step S35 can be confirmed to be data based on the export company A. Processing using the converted document data stored in the storage device can be continued (step S91). By performing such a process, for example, even if the predetermined format conversion is performed by the RSP server 7 of the domestic RSP center B, the converted document data acquired by the importing company D is obtained. However, it is certainly possible to obtain confirmation that the data is based on the export company A, and appropriate data exchange will be carried out. In FIG. 6, the encrypted document data 411 after the format conversion of (B) and the encrypted document data 4 21 after the format conversion of (C) are the same in FIG. As you can see, it is actually different data because the one-time secret key used is different. Similarly, the encryption noise value 431 of the document data after the format conversion in (D) and the encryption noise value 441 of the document data after the format conversion in (E), and the encrypted digital certificate of (F) The issue number 4 51 and the encrypted digital certificate (G) issue number 4 61 are also different data because the one-time common key is different. The digital signature 412 of B in (B) and the digital signature 452 of B in (F) are also different data because the underlying hash value is different. Similarly, the digital signature 422 of C in (C), the digital signature 442 of C in (E), and the digital signature 462 of C in (G) are also different data because the underlying hash values are different. It is. Note that the present invention is not limited to the above-described embodiment, and various modifications are possible. That is, in the above explanation, the verification of the exporting company A is performed using the digital certificate issue number, but the digital certificate itself may be used instead of the digital certificate issue number, Any information that can maintain uniqueness other than in the book can be used. Also, in the processing after step S47, the processing through the RSP server 9 of the overseas RSP center C has been described. May be configured to communicate directly with the RSP server 7 at the domestic RSP center B without going through the RSP server 9 at the overseas RSP center C. For the RSP server 9 of the overseas RSP center C as well as the import company D, the import company D server 5 implements if it is necessary to confirm that the converted document data is indeed data based on the export company A. What is necessary is just to perform the processing as described above.

As described in the above explanation, the verification of the digital signature failed due to falsification, etc., or the digital certificate issue number could not be obtained from the hash / digital certificate / line number index table in step S65, etc. By notifying the relevant server of a warning, the process for stopping or discarding the use of document data or document data after format conversion can be performed. Basically, the method of this notification should be transmitted to the sender in order. However, a configuration in which the importing company D or the like notifies the related servers all at once may be used. Although the example in which the pair of the hash value and the digital certificate issue number is stored in the hash and digital certificate issue number index table has been described, the data generated by any function similar to the hash value may also be used in the present embodiment. Can be handled in the same way as hash values.

Claims

The scope of the claims

1. performing a format conversion corresponding to a destination of the first data on the first data received from the first computer to generate second data;

A step of calculating a hash value of the second data, storing the hash value and information related to the electronic certificate related to the first combination in a storage device,

A first transmission step of transmitting the second data to a second computer associated with the destination;

When receiving the hash value from the second computer, reading information about the digital certificate corresponding to the received hash value from the storage device; and reading the information about the read digital certificate into the second computer. A second sending step to send to the other computer;

An information processing method including:

2. A step of generating information for a warning when information about the digital certificate corresponding to the received hash value cannot be obtained from the storage device.

The information processing method according to claim 1, further comprising:

3. The information processing method according to claim 1, wherein the information on the electronic certificate is identification information of the electronic certificate.

4. generating a digital signature using the hash value of the second data, and storing the digital signature in a storage device;

In the first transmitting step, transmitting the electronic signature to the second computer

The information processing method according to claim 1, wherein:

5. generating a second digital signature using a hash value of the read information on the digital certificate, and storing the second digital signature in a storage device;

In the second transmitting step, transmitting the second electronic signature to the second computer

The information processing method according to any one of claims 1 to 4, wherein:

6. calculating a hash value for the data received from the other computer and storing it in a storage device;

A transmitting step of transmitting the hash value to the other computer; and a step of storing information on the digital certificate in a storage device when receiving information on the digital certificate corresponding to the hash value from the other computer. Comparing the received information about the digital certificate with information about the digital certificate from which the data was generated; and

An information processing method including:

7. The information processing method according to claim 6, further comprising a step of generating information for a warning when the received information on the digital certificate and the information on the digital certificate from which the data is generated do not match. .

8. The information processing method according to claim 6, wherein the information on the digital certificate is identification information of the digital certificate.

9. generating a digital signature using the hash value of the hash value and storing the digital signature in a storage device,

9. The information processing method according to claim 6, wherein in the transmitting step, the electronic signature is transmitted to the another computer.

10. In the comparing step, information about the digital certificate of the data generator is prepared by using the information of the generator specified from the data. The information processing method according to any one of claims 6 to 9, further comprising a step of searching for and obtaining information corresponding to a certificate and a corresponding tape holder with an owner of the digital certificate.

1 1. performing a format conversion corresponding to a destination of the first data on the first data received from the first computer, and generating second data;

A step of calculating a hash value of the second data, storing the hash value in association with information related to the electronic certificate related to the first computer in a storage device,

A program for causing a computer to execute.

12. Calculating a hash value for data received from another computer and storing it in a storage device;

A transmitting step of transmitting the hash value to the other computer; and a step of storing information on the electronic certificate in a storage device when information on the electronic certificate corresponding to the hash value is received from the other computer. Comparing the received information information on the digital certificate with information on the electronic certificate from which the data was generated,

A program for causing a computer to execute.

13. A means for performing a format conversion corresponding to a destination of the first data on the first data received from the first computer to generate second data, Means for calculating a hash value of the second data, storing the hash value and information relating to the electronic certificate associated with the first computer in a storage device in association with each other,

First transmission means for transmitting the second data to a second computer associated with the destination,

Means for reading, from the storage device, information relating to the digital certificate corresponding to the received hash value; and receiving the read information relating to the electronic certificate from the second computer. A second transmission means for transmitting to the computer of

Computer system with

14. A means for calculating a hash value for data received from another computer and storing it in a storage device;

Transmitting means for transmitting the hash value to the other computer;

Means for storing the information about the digital certificate in the storage device when the information about the digital certificate corresponding to the hash value is received from the other computer; and a source of the information about the received digital certificate and the source of the data. Means for comparing the information with the digital certificate of

Computer with a 'system.

15. A storage medium storing the program according to claim 10 or 11.