JP2004072266A - Authentication method and authentication system - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To attain mutual authentication between a plurality of authentication marks under a local environment. <P>SOLUTION: A control section 11 for verifying the authenticity of a digital document to which an authentication mark is embedded is provided with: an authentication mark generating function 11a that embeds the authentication information as a watermark to uniquely particularize the authentication mark in the image information of the authentication mark and the image information of the other authentication mark and embeds the authentication information as a watermark to uniquely particularize the other authentication mark to the image information of the other authentication mark and the image information of the authentication mark; an authentication mark embedding function 11c to embed the individual authentication marks to the digital document; and a program generating function 11d that mutually compares the pieces of the authentication information included in the respective authentication marks under the local environment to generate an authentication program whereby coincidence/dissidence of the pieces of authentication information can be discriminated. <P>COPYRIGHT: (C)2004,JPO

Description

[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention relates to an authentication method and an authentication system for a digital document in which a plurality of authentication marks are embedded, and more particularly to an authentication method and an authentication method capable of verifying the authenticity of the digital document and performing mutual authentication between the respective authentication marks. About the system.
[0002]
[Prior art]
Conventionally, as a technology for guaranteeing the authenticity of a homepage, an icon-shaped mark pasted on the homepage that guarantees that the site operator has created it (hereinafter referred to as an “authentication mark”) )). By embedding authentication information capable of uniquely identifying a homepage in an image (Jpeg, Png, etc.) using a digital watermarking technique and pasting this image data on the homepage, the authentication mark can be used to impersonate the homepage. It is intended to prevent use, prevent tampering of images, and the like. Here, the authentication information includes the URL of the homepage to which the authentication mark is to be pasted (hereinafter referred to as “pasting permission URL”), the expiration date information of the authentication mark, and the like.
[0003]
Verification of the authenticity of the home page by the authentication mark is performed by the following verification of image falsification, pasting permission URL verification, validity period verification, content falsification verification or link content falsification verification.
[0004]
The verification of the falsification of the image is performed by comparing the feature value embedded in the image with the image referenced by the referrer, thereby detecting the falsification of the image.
[0005]
The above-mentioned pasting permission URL verification is performed by comparing the pasting permission URL embedded in the image with the URL of the homepage being referred to obtained from the browser, and detects an unauthorized copy of the authentication mark or the impersonation of the homepage by the comparison. is there.
[0006]
The authenticity expiration date verification is performed by comparing the expiration date information of the authentication mark embedded in the image with the date and time information of the system (computer) obtained from the OS (Operating System), thereby guaranteeing the authenticity of the homepage. Is what you do.
[0007]
The verification of the falsification of the content and the verification of falsification of the link content are performed by comparing the content feature value embedded in the image with the content feature value obtained from the content to which the authentication mark is attached. Is to be detected.
[0008]
However, in the verification method as described above, if the authentication information embedded in the image is falsified, the authenticity of the home page cannot be guaranteed even if all the verification results are normal. That is, the verification method as described above is based on the premise that the authentication information is not falsified in order to guarantee the authenticity of the homepage. For this reason, in order to solve the above-mentioned inconvenience in the authentication system using the authentication mark as described above, it is necessary to prove the identity between the authentication mark immediately after generation and the authentication mark being referred to.
[0009]
However, the person (environment) that generates the authentication mark is not always the same as the person who refers to it, and an unspecified number of people can be the referrer. It is practically difficult to hold files (data files of image information and authentication information).
[0010]
Therefore, in such an authentication system, a means for verifying the identity between the authentication mark immediately after generation and the authentication mark referred to by the reference person is taken. Such verification means stores binary data equivalent to the file of the authentication mark immediately after generation in a database, compares and verifies the binary data with the file of the authentication mark being referred to by the referrer, and verifies the verification result. This is a so-called authentication server that returns the information to the referrer. Then, based on the verification result from the authentication server, the authenticity of the home page can be confirmed even if the reference person of the authentication mark does not hold the file of the authentication mark immediately after generation.
[0011]
[Problems to be solved by the invention]
As described above, conventionally, an authentication system using an authentication mark in which authentication information such as a pasting permission URL is embedded is used to prevent impersonation of a homepage on a network such as the Internet, prevention of unauthorized use of the authentication mark, and prevention of image falsification. And so on. However, when browsing the website, it is useful because the authenticity can be confirmed by the certification mark, but it is useful. Even if multiple certification marks are affixed to a page such as a contract, there is no relationship between the certification marks, so each certification mark only independently confirms the authenticity of the page. is there. For this reason, in the conventional authentication system, mutual authentication between two or more persons who mutually use one page cannot be performed, and even if the authenticity of the page can be confirmed, the other party cannot be proved. was there.
[0012]
Also, in this conventional authentication system, since the pasting permission URL is used as authentication information for uniquely specifying a homepage, a digital document such as a homepage (HTML file) stored locally or a digital There was also the inconvenience that the authenticity of the image (hereinafter referred to as "digital document") could not be confirmed. Specifically, the conventional authentication system is based on the premise that a verification operation is performed on a network. For example, in the case of a digital document such as the above-mentioned contract where storage is performed in a local environment, the authenticity under such an environment is Cannot be verified, and its convenience is lacking. That is, a digital document such as a contract is often stored locally after the contract is concluded due to its nature, but the authenticity cannot be verified unless a network connection is made each time the reference is made. Then, when performing a reference or the like (for example, when a person other than the party involved in the contract work checks the contents), it is inconvenient for the person to be required to connect to the network each time.
[0013]
In view of the above, the present invention provides an authentication method and an authentication system which can solve the disadvantages of the conventional example and can perform mutual authentication between a plurality of authentication marks and can perform mutual authentication even in a local environment. Is its purpose.
[0014]
[Means for Solving the Problems]
In order to achieve the above object, in the authentication method according to the present invention, mutual authentication between the respective authentication marks is performed by mutually comparing coincidence / mismatch of respective authentication information of a plurality of authentication marks embedded in a digital document. I have to.
[0015]
In order to achieve the above object, in the authentication system according to the present invention, the control unit for verifying the authenticity of the digital document in which the authentication mark is embedded is provided with authentication information for uniquely identifying the authentication mark by using an image of the authentication mark. Watermarking information and image information of another authentication mark, an authentication mark generation function of watermarking the authentication information for uniquely identifying the other authentication mark into the image information of the other authentication mark and the image information of the authentication mark, The authentication mark embedding function for embedding the respective authentication marks in the digital document and the authentication information included in the respective authentication marks in a local environment can be compared with each other to determine the match / mismatch of the respective authentication information. And a program generation function for generating an authentication program.
[0016]
BEST MODE FOR CARRYING OUT THE INVENTION
One embodiment of a mutual authentication system according to the present invention will be described with reference to FIGS.
[0017]
The configuration of the mutual authentication system according to the present embodiment will be described. The mutual authentication system generates an authentication mark for each user of the present system, and affixes the authentication mark to a digital document such as an HTML format. Further, the digital document has an authentication server for pasting an authentication mark of another user on the digital document and for watermarking information that can verify the authenticity between the respective authentication marks. As shown in FIG. 1, in the present embodiment, the authentication server is exemplified as being installed in a certificate authority. The certification authority mentioned here is a third-party organization that authenticates a person (business establishment or the like) who wants to use the present system. Although only one certificate authority is shown in this embodiment, a plurality of certificate authorities may be provided. Here, as shown in FIG. 1, the authentication server 10 has terminals (hereinafter referred to as “user terminals”) 20 _k (k = 1, 2,...) Of a plurality of users (offices) using the present system. , N) are connected via a network 30 such as the Internet. Hereinafter, the authentication server 10 shown in FIG. 1 will be described.
[0018]
The authentication server 10 includes a control unit 11 in which a central processing unit (CPU) (not shown) performs processing to be described later based on a program read into a main storage device (memory) (not shown), and a program storage unit storing the program. And a storage unit 13 for storing information related to the authentication mark (authentication information such as image information and user information to be described later) and information related to a digital document (information such as description contents of the digital document).
[0019]
Specifically, the control unit 11 includes an authentication mark generation function 11a that generates an authentication mark at the request of a user, and an authentication information registration that registers information on the authentication mark and the digital document from the user in the storage unit 13. A function 11b, an authentication mark embedding function 11c for embedding an authentication mark in a digital document of the user, and a plug-in generation function 11d for generating a plug-in based on the authentication mark are provided.
[0020]
Here, the authentication mark of the present embodiment is obtained by embedding authentication information in image information such as Jpeg, Png or the like by using a digital watermark technique. As the authentication information of the present embodiment, as will be described later, user information (mark ID, mark type ID, etc.) for uniquely specifying the authentication mark when the authentication mark is attached to the digital document, and embedding of the authentication mark Although the information of the target digital document is used, a pasting permission URL as in the conventional example may be further added. By embedding such an authentication mark in a digital document, the present system makes it possible to prevent impersonation of a digital document, prevent unauthorized use of such a mark, and prevent falsification of an image. The plug-in checks the originality with a hash value, and is an authentication program for performing mutual authentication between authentication marks in a local environment.
[0021]
In order to use the above-described mutual authentication system, the user must first register with the certificate authority. Without this registration, the user cannot have the certificate authority issue an authentication mark.
[0022]
Hereinafter, a specific example of the authentication mark issuing process will be described with reference to the flowchart of FIG. The user sends image information to be visually expressed as an authentication mark from the user terminal _20k to the authentication server 10 via the network 30, and requests an authentication mark to be issued (step ST1). Upon receiving this request, the control unit 11 of the authentication server 10 checks the existence of the client, that is, determines whether or not the client has authority to use the system, by using the ID or password assigned at the time of user registration. (Step ST2).
[0023]
Here, if the result indicates that the user does not have the right to use, the process ends. If the result indicates that the user has the right to use, the authentication mark is generated by the authentication mark generation function 11a of the control unit 11 (step ST3). At the time of this generation, the authentication mark generation function 11a transmits the user information (mark ID, mark type ID, etc.) for uniquely identifying the mark when the received image information is attached to the contract as an authentication mark. Generated from information and information at the time of user registration. Then, a hash value is generated from the user information and the image information by using a hash function, and this hash value is watermarked into the image information to generate an authentication mark (hereinafter referred to as an “authentication mark original”).
[0024]
After the authentication mark original is generated, the control unit 11 registers information (user information and image information) on the authentication mark original in the storage unit 13 by the authentication information registration function 11b (step ST4). Then, since the authentication server 10 notifies the user terminal 20 _k that the original authentication mark has been generated (step ST5), the user downloads and acquires the original authentication mark from the authentication server 10 (step ST5). ST6). Note that the authentication server 10 may transmit the original authentication mark by e-mail or the like.
[0025]
When the authentication mark original issuance process is completed as described above, the user can perform the following process.
[0026]
In the following, a case where the present system is used for a contract between the two parties, the user of the mutual authentication system, will be described as a specific application example. Here, Party A is a company engaged in mail-order sales such as Internet shopping, and is a person who uses this system to expand sales of its products. In addition, Party B is a person who wishes to purchase the goods provided by Party A.
[0027]
A has set up a Web site for mail order sales. For this reason, in the present embodiment, a Web server 40 is provided on the network 30 as shown in FIG. Here, in the present embodiment, the Web server 40 also has a function of embedding the authentication information in the authentication mark. To provide such a function, a processing program is required. In the present embodiment, the program is made available by registration with the above-mentioned certificate authority.
[0028]
Here, the description will be made on the assumption that the user, the user, has obtained the original authentication mark in advance. First Party A as shown in the flowchart of FIG. 3, the self-user terminal (hereinafter referred to as "upper terminal".) 20 yuan agreement created in such ₁ (in HTML format such that the underlying public for agreement to be described later The digital document, in which only the first party is entered, and its original authentication mark original (hereinafter referred to as “the former original mark”) are transmitted to the authentication server 10 (step ST11). Thereby, the control unit 11 of the authentication server 10 determines whether or not the person who transmitted the original contract is a legitimate user (step ST12). Here, an ID, a password, and the like, which were given when the instep A was registered, are used for this determination.
[0029]
Subsequently, the authentication server 10 ends the process if the result of the determination in step ST12 is that the user is not a legitimate user, and if the result is that the user is a legitimate user, the authentication mark generation function 11a A hash value is generated by using a hash function from the original contract information (such as the input items of the former) and the image information of the original of the former mark, and this hash value is watermarked in the image information. That is, an authentication mark (hereinafter, referred to as “A mark”) in which the original contract information is added to the original A mark is generated (step ST13). Thereafter, the control section 11 registers information on the instep mark in the storage section 13 by the authentication information registration function 11b (step ST14). Here, the information on the instep A to be registered is only the original contract information because the user information and the image information have already been registered in step ST4 shown in FIG.
[0030]
Subsequently, the authentication mark embedding function 11c of the control unit 11 embeds the former mark into the original contract (step ST15) to generate a contract for publication, and the plug-in generating function 11d performs the plug-in based on the former mark. In step ST16, the public agreement and the plug-in are sent to the party A (step ST17). Then, Party A publishes the disclosure contract and the plug-in on the Web site (Step ST18).
[0031]
Next, actual contract processing with the second party, that is, the case where the second party purchases a desired product from the product information listed on the public website of the first party will be described with reference to the flowcharts shown in FIGS. Here, if the second party has not been registered with the certificate authority, firstly, the second party performs the registration and performs the above-described steps ST1 to ST6 shown in FIG. Then, the following contract processing is performed. In addition, if the original of the Mark B has already been acquired, the processing proceeds to the following contract processing.
[0032]
When purchasing a desired product from the product information listed on the public website of the Party A, as shown in the flowchart of FIG. 4, the Party B sends the order form (digital document in HTML format or the like) from the website to its own. user terminal (hereinafter referred to as the "second terminal".) 20 ₂ download to (step ST21). Then, predetermined items are entered in the order form, and transmitted to the authentication server 10 together with the original authentication mark (hereinafter referred to as “Otsu mark original”) (step ST22).
[0033]
The control unit 11 of the authentication server 10 determines whether or not the person who transmitted the order form is a legitimate user by using the ID and password given at the time of registration of the party (step ST23). If it is determined that the user is not the user, the process ends. If the result indicates that the user is a legitimate user, the authentication mark generation function 11a generates a hash value from the URL information on the instep side and the hash function, and converts the hash value into the image information of the original mark O. A watermark is embedded (step ST24), and the second mark is embedded in the order form (step ST25). Thereafter, the control unit 11 returns the order to the customer (step ST26), and the customer uploads the order to the website of the customer (step ST27). Party A downloads the order form from the Web site and confirms Party B in the conventional manner based on Party A's URL information watermarked in Party B's mark (step ST28). If it is confirmed by this confirmation that Party B is a valid person, Party A makes an estimate, notifies Party B that a contract is to be prepared (Step ST29), and prepares a contract as follows.
[0034]
As shown in the flowchart of FIG. 5, the _second party transmits the original mark of the second party to the web server 40 via the network 30 from the second terminal 202 (step ST31). The Web server 40 registers the information of the original Otsu mark (user information of Otsu) in the storage unit (not shown) by the authentication mark registration function 41a of the control unit 41 shown in FIG. 1 (step ST32). The download of the public agreement and the plug-in is permitted (step ST33). Thus, Party B, downloaded from the instep public Web site of the public agreement Party B terminal 20 ₂ (step ST34), and enter the Client descriptive matter in this publication for agreement, the publishing agreement sending the Client mark original from Party B terminal 20 ₂ to the authentication server 10 of the certificate authority along with writing (step ST35).
[0035]
The control unit 11 of the authentication server 10 that has received these determines whether or not the sender is a legitimate user, using the ID and password given at the time of registration (step ST36). Here, if the result is that the user is not a legitimate user, the process ends. If the result indicates that the user is a legitimate user, the authentication mark generation function 11a uses the hash function to obtain a hash value from the contract information for publication (such as the input items of Kotsu Otsu) and the image information of Otsu Mark original. Is generated, and the hash value and the hash value of the user information of the instep mark embedded in the public agreement are watermarked in the image information of the original mark B (step ST37). That is, an authentication mark (hereinafter referred to as "Otsu Mark") in which the contract information for disclosure and the user information of Party A are added to the Original Otsu Mark is generated.
[0036]
Subsequently, the authentication mark generation function 11a watermarks the user information of the user B into the image information of the instep A embedded in the contract for disclosure (step ST38), and further discloses the user B mark by the authentication mark embedding function 11c. A temporary contract is created by embedding it in the business contract (step ST39). Then, the authentication server 10 transmits the _second mark and the provisional contract to the second terminal 202 (step ST40). Here, in the above steps ST37 and ST38, URL information of the Web site of the Party A, which is the storage destination of the contract after the conclusion of the contract between Party A and Party B, may be watermarked.
[0037]
Next, as shown in the flowchart of FIG. 6, the second party receiving the second party mark and the temporary agreement from the certificate authority transmits the _second party mark and the temporary agreement to the web server 40 via the network 30 from the _second party terminal 202. (Step ST41). Thereby, the Web server 40 registers the information of the second party mark (user information of the second party) in the storage section (not shown) by the authentication mark registration function 41a of the control section 41 (step ST42).
[0038]
Subsequently, the control unit 41 uses the verification function 41b shown in FIG. 1 to store the information (user information) of the second mark and the information (first information) of the second mark registered in the storage unit 22 in step ST32 shown in FIG. The user information is compared and verified, and the user is authenticated (step ST43). If the user information does not match, the process is terminated. If the user information does not match, the hash value of the provisional contract (the watermark (The same as the hash value of the published contract) (step ST44), and the provisional contract is stored as a final contract in a storage unit (not shown) (step ST45). Jia, store download this final agreement instep terminal 20 ₁ from the Web site (step ST46). Then, download and reference of this final contract by the second party are permitted (step ST47). As a result, the Party B, store and download the final contract from the Web site in Otsu terminal 20 ₂ (step ST48).
[0039]
As shown in FIG. 7A, the contract prepared as described above is affixed with the A and B marks. Furthermore, each mark is watermarked with the user information of each party. Therefore, even in a local environment (that is, even when the plug-in is not connected to the network 30), the above-described plug-in compares and verifies the A-mark and the O-mark, and thus, specifically, the A-mark and the O-mark. By reading and comparing respective pieces of user information from the marks and determining the match / mismatch, it is possible to prove the identity between the mark immediately after generation and the currently referred mark. Thus, it is possible to confirm the falsification of each mark or the impersonation of the authentication mark of another person as shown in FIG. 7B.
[0040]
Here, although not shown, if the user information matches as a result of authentication by the plug-in (that is, there is no falsification of the authentication mark), a valid authentication mark is displayed on the screen displaying the digital document. A message to that effect is displayed. In the case of a mismatch (that is, the authentication mark has been tampered with), error information is displayed on the screen, further indicating that the contract partner is inappropriate and that the contract has not been established.
[0041]
Further, since the authentication is performed by the plug-in corresponding to only the authentication mark generated as described above, the possibility that the authentication mark is stolen by a third party and misused is reduced. Further, since no password is used for such authentication, there is no need to remember the password, and the convenience of the user is improved.
[0042]
Further, since the information of the contract is watermarked in each mark, it is possible to confirm whether the contract has been tampered with.
[0043]
Note that the above-described user information and the like watermarked in the image information are encrypted and watermarked by, for example, an electronic signature technique. For this reason, the possibility that the authentication information included in the authentication mark is stolen by a third party is reduced, so that falsification of the digital document and the authentication mark can be prevented, and the validity of the authentication result can be improved.
[0044]
In the present embodiment described above, the authentication server 10 is installed in the certificate authority. However, the present invention is not necessarily limited to this. In such a case, integration with the Web server 40 on the instep side may be achieved.
[0045]
Further, when a plurality of certificate authorities are used, that is, when each party uses a separate certificate authority, information is shared between the respective certificate authorities. Specifically, the certificate authority that has issued the original authentication mark transmits the registration information of step ST4 shown in FIG. 2 to another certificate authority. The certification authority that has performed the process of embedding the certification information in the certification mark transmits the certification information to another certification authority. As a result, if information can be shared among the certificate authorities, tampering of the authentication mark or the like can be confirmed at the time of watermarking processing, and it is possible to further improve authentication accuracy.
[0046]
【The invention's effect】
According to the authentication method and the authentication system of the present invention, when referring to a digital document in a local environment, the authentication information of the self-authentication mark attached to the digital document and the authentication of the authentication mark of another person By comparing the information with the information, mutual authentication between the respective authentication marks becomes possible, and the impersonation of the other party viewed from one side, that is, for example, the second party viewed from the instep can be prevented.
[Brief description of the drawings]
FIG. 1 is a block diagram showing an embodiment of a mutual authentication system according to the present invention.
FIG. 2 is a flowchart illustrating an authentication mark original issue process of the present system.
FIG. 3 is a flowchart illustrating an open contract creation process using the present system.
FIG. 4 is a flowchart illustrating a process at the time of ordering according to the embodiment.
FIG. 5 is a flowchart illustrating processing when a contract is created in the embodiment.
FIG. 6 is a flowchart illustrating processing at the time of creating a contract in the present embodiment, and is a view showing a continuation of FIG. 5;
FIG. 7 is a diagram showing a created contract, in which FIG. 7 (a) is a diagram created without tampering between the parties A and B, and FIG. 7 (b) shows a case where the authentication mark of the party B is tampered with; FIG.
[Explanation of symbols]
10 Authentication Server 11 Control Unit 11a Authentication Mark Generation Function 11b Authentication Information Registration Function 11c Authentication Mark Embedding Function 11d Plug-in Generation Function 20 _k (k = 1, 2,..., N) User Terminal 30 Network 40 Web Server 41 Control Unit 41a Authentication mark registration function 41b Verification function

Claims (4)

In an authentication method for verifying the authenticity of a digital document in which the certification mark is embedded based on the certification information included in the certification mark,
An authentication method, characterized in that mutual matching between the respective authentication marks of the plurality of authentication marks embedded in the digital document is compared with each other to perform mutual authentication between the respective authentication marks. 2. The authentication method according to claim 1, wherein when the authentication information does not match as a result of the mutual comparison, error information is displayed on a screen. In an authentication system having a control unit capable of verifying the authenticity of a digital document in which the authentication mark is embedded based on the authentication information included in the authentication mark,
In the control unit,
The authentication information for uniquely identifying the authentication mark is watermarked in the image information of the authentication mark and the image information of the other authentication mark, and the authentication information for uniquely identifying the other authentication mark is compared with the image information of the other authentication mark. An authentication mark generation function for watermarking the image information of the authentication mark;
The authentication mark embedding function for embedding the respective authentication marks in the digital document and the authentication information included in the respective authentication marks in a local environment can be compared with each other to determine the match / mismatch of the respective authentication information. A program generation function for generating an authentication program;
Authentication system characterized by having provided. The authentication system according to claim 3, wherein the authentication program is configured to display error information on a screen when authentication information does not match as a result of the mutual comparison.

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