JP2007183736A - Authentication system and authentication method - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an authentication system and an authentication method, which verifies that a client's system is free from defect (virus, alteration, etc.). <P>SOLUTION: An authentication server 20 includes a second file information table 23 having the same content as a first file information table owned by a plurality of clients 10. Each client 10 and the authentication server 20 form a first authentication key k1 and a second authentication key k2, based on first file information f1 and second file information f2, respectively. The authentication server 20 collates the first authentication key k1 with the second authentication key k2, permits a service when the both are identical, and rejects the service when the both differ from each other. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to an authentication system and an authentication method. Specifically, the present invention relates to an authentication system and an authentication method for authenticating that a client system is not an abnormal system.

  Today, when accessing a service, various service users are authenticated, including “user authentication” using a user ID and a password. In particular, CHAP (Challenge Handshake Authentication Protocol) has high safety and is widely used as user authentication. CHAP calculates the function value (message digest function value) using the user ID, password and random value sent from the server as a seed, and compares the function value calculated by the client with the function value calculated by the server. The user authentication method permits access if they are the same, and denies access if they are different.

  However, in such “user authentication” using a user ID and password, the service can be easily accessed from any system as long as the user can know the correct user ID and password. Under such circumstances, there has been proposed a method of prohibiting access from an unauthorized system using spoofing or a copy key by authenticating the system using terminal-specific information or a terminal key. (See Patent Documents 1 and 2)

JP 2002-63139 A (paragraphs 0020 to 0100, FIGS. 1 to 24, etc.) JP 2005-228299 A (paragraphs 0015-0064, FIGS. 1-9, etc.)

  However, in the method using terminal-specific information and terminal key, even if there is a defect (virus, tampering, etc.) in the client system, access to the service from that system cannot be suppressed, so secret information is taken out there is a possibility. Moreover, if there is such a defect in the client system, there is a risk of serious damage such as destruction of the authentication server, other clients, and the service system. Under such circumstances, it is desired to provide an authentication system and an authentication method that can authenticate that there is no defect (virus, tampering, etc.) in the client system.

  An object of the present invention is to provide an authentication system and an authentication method capable of prohibiting access to a service when a client system has a defect (virus, falsification, etc.) by performing “system authentication”. .

  In order to solve the above problem, an authentication system 100 according to claim 1 includes a plurality of clients 10 and an authentication server 20 as shown in FIG. 2, for example. A first file information table 13 for recording file information f1 (see FIG. 4), a first system information processing unit 14 for obtaining first file information f1 from the first file information table 13, and a first A first authentication key creating unit 15 for creating a first authentication key k1 (see FIG. 4) based on the file information f1, and the authentication server 20 is identical in origin to each first file information f1. Each second file information table 23 for recording each second file information f2 and second system information for obtaining each second file information f2 from each second file information table 23 Created by the management unit 24, the second authentication key creation unit 25 that creates each second authentication key k2 based on each second file information f2, and any client 10a among the plurality of clients 10 The first authentication key k1 and the second authentication key k2 related to the client 10a are collated. If both are the same, the system of the client 10a is normal. And a service authentication unit 27 that authenticates that the system is abnormal.

  Here, the same source means that the information sources are exactly the same. Therefore, either the first file information or the second file information is updated, altered, disaster (memory corruption, noise disturbance, etc.) ) Etc., unless changed by other means. The acquisition of the first and second file information f1 and f2 may be performed by acquiring all the file information at once, extracting a part of the file information, or acquiring some items regarding each file. Only selectively may be acquired. In addition, the creation of the first and second authentication keys k1 and k2 based on the first and second file information f1 and f2 is any information extracted from the first and second file information f1 and f2. May be used as a seed, and may include other seeds such as time and pseudo-random numbers. Moreover, although the arbitrary client 10a is limited to the client 10 which comprises a system, in this case, if it is impersonation about unauthorized access from other than a legitimate system, it will be regarded as an impersonated client in the system and abnormal. If there is an unauthorized access other than that, the second file information table handled by the client does not exist, so that the collation is not reached and it is not authenticated as normal. With this configuration, by performing “system authentication”, it is possible to provide an authentication system capable of prohibiting access to the service 40 when the system of the client 10 has a defect (virus, falsification, etc.).

  Further, the invention according to claim 2 is the authentication system according to claim 1, wherein the authentication server 20 includes a random number key creation unit 26 that creates a key seed k 0, and the first authentication key creation unit 15 includes: Based on the first file information f1, the time, and the key seed k0, the first authentication key k1 is generated using a one-way function, and the second authentication key generation unit 25 includes the second file information f2, the time, A second authentication key k2 is created using a one-way function based on the key seed k0. If comprised in this way, the reliability as an encryption key of the 1st, 2nd authentication keys k1 and k2 can be made high.

  The invention according to claim 3 is the invention of the client 10 in the authentication system according to claim 1. The invention according to claim 4 is the invention of the authentication server 20 in the authentication system according to claim 1.

  In order to solve the above-described problem, an authentication method according to claim 5 is an example of an authentication system 100 including a plurality of clients 10 and an authentication server 20 as shown in FIGS. 4 and 8. Of these, as a process in an arbitrary client 10a, a first file information recording process (S121, see FIG. 6) for recording the first file information f1 handled by the client 10a in the first file information table 13, and the first file information First system information processing step (S120) for obtaining the first file information f1 from the table 13, and a first authentication key creation step for creating the first authentication key k1 based on the first file information f1 As a process in the authentication server 20, the second file information f2 handled by the client 10a is A second file information recording step for recording in the second file information table 23 related to the event 10a, and a second system information processing step for obtaining the second file information f2 from the second file information table 23 (S220). A second authentication key creating step (S270) for creating a second authentication key k2 based on the second file information f2, a first authentication key k1 created by an arbitrary client 10a and the client A service that verifies the second authentication key k2 related to 10a and authenticates that the system of the client 10a is normal if they are the same, and that the system of the client 10a is abnormal if they are not the same And an authentication step (S280).

  With this configuration, by performing “system authentication”, it is possible to provide an authentication method capable of prohibiting access to a service when a client system has a defect (virus, falsification, etc.).

  In the authentication method according to claim 5, the authentication server 20 includes a random number key generation step (S240) for generating the key seed k0, and the first authentication key generation step (S240). In step S130, a first authentication key k1 is generated using a one-way function based on the first file information f1, time, and key seed k0 related to the client 10a, and a second authentication key generation step (S270). The second authentication key k2 is generated using a one-way function based on the second file information f2, time and key seed k0 related to the client 10a. If comprised in this way, the reliability as an encryption key of the 1st, 2nd authentication keys k1 and k2 can be made high.

According to the present invention, since the authentication key is created based on the file information of the system, the correct authentication is performed from the file information table of the system that has been affected by the virus, the system that has been tampered with, or the system that has suffered a disaster. You cannot create a key.
That is, according to the present invention, by performing “system authentication”, it is possible to provide an authentication system and an authentication method capable of prohibiting access to a service when a client system has a defect (virus, falsification, etc.).

  Embodiments of the present invention will be described below with reference to the drawings.

  FIG. 1 is a diagram for explaining the concept of the present invention. When controlling access for receiving a service to a client, conventionally, if user authentication can be performed, the access is permitted through the gateway. However, in the present invention, when the client 10 requests access to the service, the authentication server 20 incorporates a system authentication (function) 20A for judging the quality of the system used by the user in addition to the user authentication (function) 20B, and the system of the client 10 is affected by a virus, altered, or disaster After confirming that the system is not an abnormal system such as receiving a message or an access request from an unauthorized system such as impersonation, the service is passed through the gateway 30 to receive the service 40. The access control means 50 is indicated by a broken line frame.

[First Embodiment]
FIG. 2 shows a configuration example of the authentication system 100 according to the first embodiment. For convenience of explanation, only the system authentication system is displayed, and the description of the user authentication system is omitted. This system includes a plurality of clients 10 and one authentication server 20. The client 10 and the authentication server 20 are connected via the communication line 60, but may be connected via a network. In the following drawings, the notations “first” and “second” are omitted for simplicity.

  Each client 10 controls a client system as a whole, a first overall control unit 11 that causes each unit to execute necessary processing, a first communication control unit 12 that performs transmission and reception with an external device including an authentication server 20, A first file information table (abbreviation of FIT: File Information Table) 13 in which the first file information f1 handled by the client is recorded, data input / output to / from the first file information table 13, and the first to operate The system information processing unit 14 includes a first authentication key creating unit 15 that creates the first authentication key k1 based on the first file information f1.

  The authentication server 20 controls the entire system of the authentication server, a second overall control unit 21 that causes each unit to execute necessary processing, and a second communication control unit 22 that performs transmission / reception with an external device including each client 10. The second file information table 23 in which the same information as each first file information table 13 relating to each client is recorded, the second input / output operation of data to the second file information table, the second operation, etc. The system information processing unit 24, the second authentication key generation unit 25 that generates each second authentication key k2 based on each second file information f2, the key seed k0 from the fifth file information f5 (described later) and a random number The random number key generation unit 26 for generating the first authentication key k1 generated by an arbitrary client 10a and the second authentication key k2 associated with the client 10a are compared and collated. With a service authentication unit 27 for non-certification. A collection of the second file information tables 23 is referred to as an all file information table 23A, and a collection of the second file information f2 is referred to as an all file information. The fifth file information f5 is typically extracted from the second file information f2, but may be extracted from all file information.

  Next, the relationship between the first file information table 13 and the second file information table 23 will be described. The first file information table 13 related to each client 10 and the second file information table 23 related to each client 10 have the same origin (information source) and originally share the same information. Furthermore, since the first file information table 13 is not rewritten in principle, the first file information table 13 and the second file information table 23 have the same contents when the system is maintained normally. ing. In addition, when it becomes necessary to update one of the first file information table 13 or the second file information table 23, both are updated so that the contents are identical. However, if any client 10a is accessed from the outside and altered, or if it is infected with a virus or suffers a disaster such as memory corruption or noise disturbance, the contents of the first file information table 13 are Change. In such a case, not only one location of the file information but also many portions are affected and variously change. When the system of the client 10a is normal, the first file information table 13 and the second file information table 23 have the same contents, and therefore the first created from the key seed k0 and the first file information f1. The first authentication key k1, the second seed key k2 created by the same procedure from the key seed k0 and the second file information f2 are the same, and the system of the client 10a is authenticated as normal. When the system is abnormal, the first file information table 13 and the second file information table 23 are changed to different contents, so the first seed created from the key seed k0 and the first file information f1. The authentication key k1, the key seed k0, and the second authentication key k2 created from the second file information f2 are different from each other. Ant 10a system is authenticated as abnormal.

  FIG. 3 shows a processing flow example of the system authentication method in the present embodiment. In the figure, the processing flow of the client 10 is shown in the left column, the processing flow of the authentication server 20 is shown in the middle column, and the gateway 30 and the service 40 are shown in the right column. First, the client 10 requests access to the authentication server 20. At this time, a file information table identifier X for identifying a system used by each client 10 is supplied from the client 10 to the authentication server 20 (S100).

Next, the authentication server 20 identifies the system of the client 10a that requested the access by the file information table identifier X in the second overall control unit 21, and from the second file information table 23, the fifth server 10a associated with the client 10a is identified. The random number key generation unit 26 generates a random number key as the key seed k0 using the extracted fifth file information f5 and the random number generated by itself (S240). The fifth file information f5 may be a part of the second file information f2, for example, one block.
Next, the authentication server 20 supplies the key seed k0 to the client 10a (S250).

  Next, the client 10a uses the first authentication key creation unit 15 to extract the third file extracted from the first file information table 13 in which the key seed k0 and the first file information f1 handled by the client 10a that requested access are recorded. A first authentication key k1 is created based on the information f3 (S130). The extracted third file information f3 may be a part of the first file information, for example, 1%. Since the third file information f3 is based on the first file information f1, it can be said that the first authentication key k1 is created based on the first file information f1.

On the other hand, the authentication server 20 uses the second authentication key creation unit 25 based on the key seed k0 and the fourth file information f4 extracted from the second file information table 23 related to the client 10a that requested access. The authentication key k2 is created (S270). The extracted fourth file information f4 may be a part of the second file information, for example, 1%. However, the step of creating the first authentication key k1 and the step of creating the second authentication key k2 differ only in the location of the data, and are in exactly the same procedure. Since the fourth file information f4 is based on the second file information f2, it can be said that the second authentication key k2 is created based on the second file information f2.
Next, the client 10a transmits the created first authentication key k1 to the authentication server 20 (S140).

Next, in the service authentication unit 27, the authentication server 20 compares and collates the first authentication key k1 created by the client 10a with the second authentication key k2 created by the authentication server 20 (S280). In this case, authentication that the client 10a system is normal is performed, that is, the gateway 30 is opened and the access to the service 40 is permitted (S291, see FIG. 11). Authentication that is abnormal, that is, a decision to close the gateway 30 and deny access to the service 40 from the client 10a is made (S292, see FIG. 11).
The authentication result by the authentication server 20 is notified to the client 10 and the gateway 30 (S293 to S295), and when it is authenticated as normal, services from the various service servers 40 to the client 10 are executed (S300).

  Next, the processing flow of each unit will be described in detail. First, the processing flow of each unit on the client side will be described.

  FIG. 4 shows a processing flow example of the first overall control unit 11. The file information table identifier X is transmitted from the first communication control unit 12 to the second communication control unit 22 (S100). Next, the reception of the key seed k0 from the second communication control unit 22 in the first communication control unit 12 is monitored, and if received (Y in S110), the first system information processing unit 14 is notified with its own file information. A certain first file information f1 is acquired (S120), the key seed k0 and the first file information f1 are supplied to the first authentication key creating unit 15, and the first authentication key k1 is created (S130). The first communication control unit 12 causes the second communication control unit 22 to transmit the first authentication key k1 created by the first authentication key creation unit 15 (S140). Here, the first system information processing unit 14 acquires all of the first file information f1, but a part of the first file information f1 can also be acquired. In addition, although all the first file information f1 is supplied to the first authentication key creation unit 15, a part of the first file information f1 can be supplied. If the key seed k0 has not been received (N in S110), the file information table corresponding to the file information table identifier X does not exist, and the process ends. The overall control unit 11 controls the processing flow of the entire client 10 and causes each component unit to execute necessary processing.

  FIG. 5 shows an example of the processing flow of the first communication control unit 12. Regarding the transmission process, first, an encrypted communication path is established (S101). For encryption of the communication path, for example, a combination of a public key and a secret key, a common key, or the like is used. Next, communication data is received from the first overall control unit 11 (S102), and communication data such as a message is transmitted to the communication partner (S103). Such communication processing is applied to transmission of the file information table identifier X (S100, see FIGS. 3 and 4), transmission of the first authentication key k1 (S140, see FIGS. 3 and 4), and the like. As for the reception process, communication data such as a message is received from the communication partner (S104) and transmitted to the first overall control unit 11 (S105). This is applied to reception of the key seed k0 (S250, see FIGS. 3 and 8) and the like.

  The processing flow of the second communication control unit 22 is the same as the processing flow of the first communication control unit 12 for both transmission and reception, transmission of the key seed k0 (S250), notification of the authentication result (S294, S295, FIG. 3, FIG. 8). The file information table identifier X is received (S100), and the first authentication key k1 is received (S140). Note that the process flow steps (S101 to S105) of the first communication control unit 12 correspond to the process flow steps (S201 to S205, not shown) of the second communication control unit 22.

  FIG. 6 shows a processing flow example of the first system information processing unit 14. This corresponds to step S120 in FIG. First, the first file information f1 handled by the client 10 is recorded in the first file information table 13 (S121). Once this recording process is performed, it is not necessary to perform the recording process as long as the first file information is not updated. In addition, if the file information is automatically created, there is no need to perform this recording process. . When receiving the file information acquisition request from the first overall control unit 11 (S122), the first system information processing unit 14 accesses the first file information table 13 and obtains the first file information f1. Obtained (S123), and the obtained first file information f1 is supplied to the first overall control unit 11 (S124). Here, the first file information f1 is collectively acquired. However, the first file information f1 may be divided into blocks, and only necessary blocks may be extracted and acquired. The normal system of the client 10 has a large number of files. For example, the system is divided into 10,000 blocks, and one block is formed for every five files, and for example, 50 blocks may be acquired.

  FIG. 7 shows a processing flow example of the first authentication key creation unit 15. This corresponds to step S130 in FIG. First, the first file information f1 acquired by the first system information processing unit 14 is acquired via the first overall control unit 11 (S131). Note that the first file information f1 is transferred from the first system information processing unit 14 to the first authentication key creating unit 15 under the control of the first general control unit 11 instead of going through the first general control unit 11. You may make it supply directly to. Here, the first file information f1 is collectively acquired. However, the first file information f1 may be divided into blocks, and only necessary blocks may be extracted and acquired. Next, the first counter C1 is set to 0, and a first buffer B1 for temporarily storing N blocks of the first file information f1 in the internal memory of the first authentication key creating unit 15 is created (S132). . Next, for example, a pseudo random number is generated by a strand function using the current time and the key seed k0 as arguments, and a file information number H is generated (S133). Next, the H-th block file information is acquired from the first file information f1 acquired by the first overall control unit 11 (recorded in the first file information table 13), and the first The data is input to the first memory of the buffer B1 (S134). Thereby, the file information of the Hth block is stored in the first memory of the first buffer B1.

  Next, the first counter C1 is incremented (S135). Next, returning to step S133, the steps from file information number generation (S133) to increment (S135) are repeated until the first counter C1 becomes N (S136), and as a result, the first buffer The first to Nth memories of B1 have block numbers H randomly selected from the first file information f1 using pseudorandom numbers generated by the strand function (also called file information numbers, which change for each memory number). The information of the block in (Yes) is extracted and stored sequentially. Thus, the file information stored in the first buffer B1 is extracted from the first file information f1, and corresponds to the third file information f3. In FIG. 7, the information of each block is shown as the third file information f3, but the third file information f3 is configured by all information input to the first buffer B1. Next, the file information stored in the first to Nth memories of the first buffer B1 is serially combined (S137), and HASH calculation processing is performed to create the first authentication key k1 (S138). . Here, the HASH function used for the HASH calculation process is a one-way function. If the same information is used as a seed, the same authentication key can be generated, but the seed cannot be generated from the authentication key. This enables authentication and ensures the security of the authentication key. The created first authentication key k1 is supplied to the first overall control unit 11 (S139).

  The processing flow of the second authentication key creation unit 25 is the same as the processing flow of the first authentication key creation unit 15. First overall control unit 11, first file information table 13, first system information processing unit 14, first authentication key creation unit 15, first buffer B1, first counter C1, first authentication Instead of the key k1, the second overall control unit 21, the second file information table 23, the second system information processing unit 24, the second authentication key creation unit 25, the second buffer B2, and the second counter Although C2 and the second authentication key k2 are involved, only the location of the data to be handled is different, and the processing contents are completely the same. However, the second file information table 23 related to the same client as the first file information table 13 related to the client 10a that requested access is used. The file information stored in the second buffer B2 is extracted from the second file information f2, and corresponds to the fourth file information f4. Note that the processing flow steps (S270, S271 to S279, not shown) of the second authentication key generation unit 25 correspond to the processing flow steps (S130, S131 to S139) of the first authentication key generation unit 15. It shall be.

  Next, the processing flow of each unit on the authentication server side will be described.

  FIG. 8 shows a processing flow example of the second overall control unit 21. Communication data such as a message from the client 10a that requested access is acquired via the second communication control unit 22 (S200), and the type of communication data is determined (S210). If the communication data is the authentication key k1, the process proceeds to step S260. If the communication data is the file information table identifier X, the second system information processing unit 24 determines the file information table identifier X, and the second information related to the client 10a that has transmitted the identifier to which this identifier is assigned. The file information table 23 is accessed (S220), and the presence / absence of the second file information f2 is determined (S230). If the access request is from a system that is not registered as a client of the authentication system 100 and is not permitted to access, the second file information table 23 related to the client 10a does not exist (N in S230). Without proceeding, go to step S290 and do not allow access. If it is an access request from a system that is registered as the client 10 of the authentication system 100 and is permitted to access, the second file information table 23 related to the client 10a exists (Y in S230). Next, the random key generation unit 26 generates the key seed k0 (S240), transmits the generated key seed k0 from the second communication control unit 22 to the first communication control unit 12 (S250), and waits. Return to state.

  If the communication data is the first authentication key k1, the process proceeds to step S260. The second file information table 23 related to the client 10a that requested the access to the second system information processing unit 24 is accessed, and the second file information f2 related to the client 10a is acquired (S260). Next, the key seed k0 and the second file information f2 are supplied to the second authentication key creating unit 25 to create the second authentication key k2 (S270). Next, the service authentication unit 27 is supplied with the first authentication key k1 and the second authentication key k2 to perform system authentication (S280). Here, the second system information processing unit 24 is caused to acquire all of the second file information f2, but a part of the second file information f2 can also be acquired. Further, all the second file information f2 is supplied to the second authentication key creating unit 25, but a part of the second file information f2 can be supplied. Next, the second communication control unit 22 is notified of the result of system authentication to the client 10a and the gateway 30 (S290), and returns to the standby state. When the system of the client 10a is authenticated as normal, the gateway 30 is opened, and services from the various service servers 40 to the client 10 are executed (S300, see FIG. 3).

  FIG. 9 shows a processing flow example of the second system information processing unit 24. This corresponds to step S220 in FIG. The file information table identifier X from the client 10 is acquired from the second overall control unit 21 via the second communication control unit 22 (S221), and the second counter C2 is set to 0 (S222). Next, it is determined which client 10 the acquired file information table identifier X relates to (S223).

  If all the file information tables 23A are collated sequentially, and the file information table identifier X of each collated file information table 23 is different from the file information table identifier X of the client 10a that transmitted the identifier (N in S223), the second Counter C2 is incremented (S226), and the process returns to step S223 via step S227. The second counter C2 is incremented until the corresponding client is found or becomes N (Y in S227), and if it becomes N (N in S227), the file information table 23 of the corresponding client does not exist, and thus the access is made. Is transmitted to the second overall control unit 21 (S228). If the file information table identifier X of the corresponding client is found (Y in S223), the second file information f2 is acquired from the second file information table 23 related to the client (S224), and the acquired second file Information f2 is provided to the second overall control unit 21 (S225). Here, the acquisition of the second file information f2 is acquired in a lump. However, the second file information f2 may be divided into blocks, and only necessary blocks may be extracted and acquired.

  FIG. 10 shows a processing flow example of the random number key generation unit 26. This corresponds to step S240 in FIG. First, the fifth file information f5 is acquired from the second file information table 23 related to the client 10a that has made an access request from the second overall control unit 21 (S241). The fifth file information f5 may be a part of the second file information f2, for example, one block. The fifth file information f5 does not necessarily have to be extracted from the second file information f2 related to the client 10a that requested access, but here it is extracted from the second file information f2 related to the client 10a. It shall be. Next, a key seed k0 is created from the acquired fifth file information f5 and a pseudo random number (S242). For example, the pseudo random number can be created by a strand function having the current time as an argument. Next, the created key seed k0 is supplied to the second overall control unit 21 (S243).

  FIG. 11 shows an example of the processing flow of the service authentication unit 27. This corresponds to steps S280 and S290 in FIG. First, the first authentication key k1 and the second authentication key k2 respectively created by the first authentication key creation unit 15 and the second authentication key creation unit 25 are acquired from the second overall control unit 21 ( S281). Next, it is determined whether or not the first authentication key k1 and the second authentication key k2 match (S282). If they match (Y in S282), it is determined that the system of the client 10a that requested access is normal, the gateway 30 is opened, and the access to the service 40 is permitted (S291), and the network identifier of the client 10a is determined. Is transmitted to the gateway 30 (S293), and an access permission message is transmitted to the second overall control unit 21 (S294). If they do not match (N in S282), it is determined that the system of the client 10a is abnormal, the gateway 30 is closed, and the access to the service 40 is not permitted (S292), and the second overall control unit 21 is determined. An access non-permission message is transmitted to (S295).

  FIG. 12 shows a configuration example of the first file information table 13. The first file information table 13 includes a file system information subtable and a file information subtable. In the file system information sub-table, the file system creation date, block size, total number of blocks, number of free blocks, number of mounts, last mount time, last write time, etc. are set as item fields. Items that fall under are recorded. In the file information sub-table, the file No. , File type, file name, access right, owner user ID, group ID, file size, last file access time, last file write time, etc. are set, and items corresponding to each file item are recorded in each cell Has been. It is assumed that such file information is composed of, for example, one file system information, one block, and five files of information, and one block is composed of 10,000 blocks as a whole. In the first authentication key creation step (S130, see FIG. 7) in the first authentication key creation unit 15, for example, 50 blocks are extracted in a random order (S133 to S134), and connected serially (S137). The first authentication key k1 is created by being encrypted by the one-way function (S138). The file information block constitutes a part of the block described in the file system information sub-table, but the file information number H (block number) is a value that does not exceed the total number of blocks, for example, 10,000 blocks. Only the blocks in which the file information tables 13 and 23 of No. 2 are recorded are collected and numbered.

  By the way, when the client 10 is invaded by a virus, the client 10 is falsified by an unauthorized access person, or the client 10 suffers a disaster, the file information is changed by adding, deleting, or correcting the file. When a file is added, the file number is added to the new file. , File names, etc. are set, and for example, numbers are assigned to X1 to Xnth (not necessarily serial numbers). These are not necessarily final numbers. No. is not limited to the number assigned after the vacant No. Can also be inserted. Further, it is assumed that, for example, the Y1 to Ynth (not necessarily serial number) files that have been deleted so far are deleted. Further, for example, it is assumed that the Z1 to Znth (not necessarily serial number) files are modified. When corrected, the file size, the last file access time, the last file write time, etc. are updated. Also, file system information such as a file name, access right, owner user ID, etc. that should not be changed may be updated. In addition, addition, deletion, and correction of these files may cause new blocks, disappear old blocks, or change the block length. As a result, the contents of the block also change. Then, if these changed blocks enter the extracted 50 blocks, the first authentication key k1 created in the first authentication key creation step (S130) is different from the original one. The first authentication key k1 and the second authentication key k2 are different. Further, by connecting the blocks stored in each memory of the first buffer B1 serially, if the size of the block stored in any of the memories is different, the character string (or symbol) of the serially connected data The first authentication key k1 created in the first authentication key creation step (S130) is different from the original one as a result, and as a result, the first authentication key k1 and the second authentication key k1 This is different from the authentication key k2. Normally, when a virus is accessed, many files such as system files are affected. For example, if 50 blocks are collected at random, there is a high probability that one of the blocks has been changed. It is possible to detect file changes.

  The configuration and data contents of the second file information table 23 are a copy of the original contents of the first file information table 13, and are originally the same as the configuration and data contents of the first file information table 13. . Therefore, if the client 10a is not accessed and the file content is not changed, the first file information f1 recorded in the first file information table 13 is the second file recorded in the second file information table 23. Therefore, the first authentication key k1 created based on the first file information f1 and the second authentication key k2 created based on the second file information f2 are held exactly the same as the information f2. In the service authentication step (S280) by the service authentication unit 27, the system of the client 10a is recognized as normal, and access to the service 40 is permitted.

  If the first file information f1 is changed, the file information in the first file information table 13 is changed as a result, and any one of the extracted 50 blocks is changed, and the first file information f1 is changed based on the first file information f1. If there is a difference between the first authentication key k1 created in step S2 and the second authentication key k2 created based on the second file information f2, the client in the service authentication step (S280) by the service authentication unit 27 The system of 10a is recognized as abnormal, and access to the service 40 is not permitted.

[Second Embodiment]
In the first embodiment, in the first authentication key creation step (S130), blocks randomly extracted from the first file information table 13 using pseudorandom numbers are stored in each memory of the first buffer B1. An example has been described in which the first authentication key k1 is created by connecting these blocks serially (the information input to the first buffer corresponds to the third file information). In this embodiment, each block input to each memory of the first buffer B1 is replaced again and then connected serially.

  FIG. 13 shows an example of changing the order of blocks by transferring the memory contents from the first buffer B1 to the third buffer B3. The arrangement of the blocks before and after the rearrangement is determined using pseudo random numbers. Note that the replacement of the block order does not affect the difference between the first authentication key k1 and the second authentication key k2, but increases the reliability of the encryption key. Also in this method, the first authentication key k1 is created based on the first file information f1, and if the first information f1 is changed, the first authentication key k1 is created similarly to the first embodiment. Since the authentication key k1 and the second authentication key k2 are different, the same authentication result as in the first embodiment can be obtained. It is assumed that the same processing is performed in the second authentication key creation step (S270).

[Third Embodiment]
In the first embodiment, an example in which, for example, 50 blocks are extracted in a random order in the first authentication key creation step (S130) has been described. In the present embodiment, the first system information processing step In (S120), 50 blocks are extracted from the first file information table 13 in advance. In this case, in the first authentication key creation step (S130), the step of extracting the blocks in a random order may be replaced with the step of rearranging the blocks. Also in this method, the first authentication key k1 is created based on the first file information f1, and if the first file information f1 is changed, the first authentication key k1 is created similarly to the first embodiment. Since the first authentication key k1 and the second authentication key k2 are different, the same authentication result as in the first embodiment can be obtained. The same processing is performed in the second system information processing step (S220) and the second authentication key creation step (S270).

[Fourth Embodiment]
In the first embodiment, the example in which the first and second authentication keys k1 and k2 are created based on the first and second file information f1 and f2, the time, and the key seed k0 has been described. In the embodiment, the first and second authentication keys k1 and k2 are created without using the time and the key seed k0. That is, for example, 50 blocks are extracted and input in a random order to the first and second buffers B1 and B2 using pseudo-random numbers generated without using time and key seed k0. Even in this case, if the first file information f1 is changed, the first authentication key k1 and the second authentication key k2 created in the same manner as in the first embodiment are different. An authentication result similar to that of the form is obtained. It is assumed that the same processing is performed in the second authentication key creation step (S270).

[Fifth Embodiment]
In the first embodiment, the first and second file information tables f1 and f2 are obtained from the first and second file information tables 13 and 23, the first and second system information processing units 14 and 24, and the first information. In the present embodiment, the first and second authentication key creation units 15 and 25 are all acquired through the second overall control units 11 and 21. Under the control of the overall control units 11 and 21, the first and second system information processing units 14 and 24 randomly extract, for example, 50 blocks from the first and second file information tables 13 and 23, and the first This is an example of inputting directly to the first and second buffers B1 and B2 of the second authentication key creating units 15 and 25. Thus, the file information input to the first and second buffers B1 and B2 is extracted from the first and second file information f1 and f2, and the third and fourth file information f3 and f4. It corresponds to. Even if it does in this way, since it becomes the same as the 1st implementation process after writing to the 1st and 2nd buffers B1 and B2, if the 1st file information is changed, the 1st embodiment Since the first authentication key k1 and the second authentication key k2 created in the same manner as described above are different, the same authentication result as in the first embodiment can be obtained. The same processing is performed in the second system information processing step (S220) and the second authentication key creation step (S270). Further, when acquiring the fifth file information f5 from the second file information table 23, only that portion can be extracted.

[Sixth Embodiment]
In the present embodiment, in addition to the supply and acquisition of the first and second file information f1 and f2 in the fifth embodiment, the first and second overall control units 11 and 21 control the first and second file information f1 and f2. Supply and acquisition of the key seed k0 from the second system information processing unit 24 to the second communication control unit 22 and from the first communication control unit 12 to the first authentication key The first authentication key k1 is supplied and acquired from the first authentication key generator 15 to the first communication control unit 12 and from the first communication control unit 12 to the service authentication unit 27. The second authentication key k2 is supplied and acquired from the second authentication key creation unit 25 to the service authentication unit 27. Even if it does in this way, since the same processing is performed only in the point that the data flow is performed without going through the first and second overall control units, the same processing is performed. If the file information is changed, the first authentication key k1 and the second authentication key k2 created in the same manner as in the first embodiment are different, and the same authentication result as in the first embodiment is obtained. It is done.

  The present invention can also be realized as a program for causing a client and an authentication server to execute the authentication method described in the above embodiments. This program may be used by being recorded in a ROM or RAM built in the client and the authentication server, may be recorded on a CD-ROM or a peripheral recording device, and read and used by the client and the authentication server. It may be downloaded from the client and the authentication server.

  Although the embodiments of the present invention have been described above, the present invention is not limited to the above-described embodiments, and it is obvious that various modifications can be made to the embodiments.

  For example, in the above embodiment, the description of the user authentication system is omitted, but it goes without saying that the authentication system according to the present invention may be provided with a user authentication system. In the above embodiment, the example in which the first file information table and the second file information table are not updated in principle has been described. However, the first file information table and the second file information table may be updated simultaneously. If updating is performed so that the identity of the contents is always secured, both file information tables may be updated periodically or as necessary. In the first to fourth embodiments, the first and second system information processing units have acquired the first and second file information in the example of acquiring all the file information. Some file information may be extracted and acquired, or only some items related to each file may be selectively acquired. In the first to sixth embodiments, the randomly extracted blocks are input to the first and second buffer memories in the first and second authentication key generation units, and the blocks are output from the memory. Although an example in which serial connection is sequentially performed has been described, the blocks may be sequentially input to the memory, the order of outputting the blocks from the memory may be randomized, and serial connection may be performed. In the above embodiment, the example in which the file information is used as the seed of the key seed has been described. However, the present invention is not limited to this. For example, only the current time may be used. In addition, the number of blocks of the first and second file information, the range of one block, the number of blocks to be extracted, the items of the first and second file information tables, the number of clients constituting the authentication system, and the like depend on the situation. Can be set to an appropriate value.

  Further, although an example in which the first file information table is changed has been described in the present embodiment, the same authentication can be performed when the second file information table is changed.

  The present invention is used in an authentication system and an authentication method for authenticating that a client is not an abnormal system.

It is a figure for demonstrating the concept of this invention. It is a figure which shows the structural example of the authentication system in 1st Embodiment. It is a figure which shows the example of a processing flow of the system authentication method in 1st Embodiment. It is a figure which shows the example of a processing flow of a 1st whole control part. It is a figure which shows the example of a processing flow of a 1st communication control part. It is a figure which shows the example of a processing flow of a 1st system information processing part. It is a figure which shows the example of a processing flow of the 1st authentication key preparation part. It is a figure which shows the example of a processing flow of a 2nd whole control part. It is a figure which shows the example of a processing flow of a 2nd system information processing part. It is a figure which shows the example of a processing flow of a random number key preparation part. It is a figure which shows the example of a processing flow of a service authentication part. It is a figure which shows the structural example of a 1st file information table. It is a figure which shows the example of transposition of the order of the block in 2nd Embodiment.

Explanation of symbols

DESCRIPTION OF SYMBOLS 10 Client 10a Client 11 which requested access 1st general control part 12 1st communication control part 13 1st file information table 14 1st system information processing part 15 1st authentication key creation part 20 Authentication server 20A System authentication 20B User authentication 21 Second overall control unit 22 Second communication control unit 23 Second file information table 23A All file information table 24 Second system information processing unit 25 Second authentication key creation unit 26 Random key creation unit 27 Service Authentication Unit 30 Gateway 40 Service 50 Access Control Unit 60 Communication Line 100 Authentication System B1 First Buffer B2 Second Buffer B3 Third Buffer f1 First File Information f2 Second File Information f3 Third File Information f4 fourth file information f5 fifth file information Information k0 key seed k1 first authentication key k2 second authentication key X file information table identifier

Claims (6)

With multiple clients and authentication server;
Each of the clients includes a first file information table that records first file information handled by the client;
A first system information processing unit for obtaining the first file information from the first file information table;
A first authentication key creation unit that creates a first authentication key based on the first file information;
The authentication server includes a second file information table that records second file information that is identical to the first file information;
A second system information processing unit for acquiring each second file information from each second file information table;
A second authentication key creating unit that creates each second authentication key based on each second file information;
A first authentication key created by an arbitrary client of the plurality of clients is compared with a second authentication key related to the client, and if both are the same, the client system is normal. A service authentication unit that authenticates that the client system is abnormal if
Authentication system. The authentication server has a random number key creation unit that creates a key seed,
The first authentication key creating unit creates the first authentication key using a one-way function based on the first file information, time, and the key seed,
The second authentication key creating unit creates each second authentication key using the one-way function based on the second file information, time, and the key seed;
The authentication system according to claim 1. A first file information table for recording first file information handled by the device;
A first system information processing unit for obtaining the first file information from the first file information table;
A first authentication key creating unit that creates a first authentication key based on the first file information;
client. Each second file information table for recording each second file information handled by each client;
A second system information processing unit for acquiring each second file information from each second file information table;
A second authentication key creating unit that creates each second authentication key based on each second file information;
A first authentication key created by an arbitrary client among the clients is compared with a second authentication key related to the client, and if both are the same, the system of the client is normal. A service authentication unit that authenticates that the client system is abnormal if it is not the same;
Authentication server. An authentication system comprising a plurality of clients and an authentication server;
A first file information recording step of recording first file information handled by the client in a first file information table as a step in an arbitrary client of the plurality of clients;
A first system information processing step for obtaining the first file information from the first file information table;
A first authentication key creating step of creating a first authentication key based on the first file information;
As a step in the authentication server, a second file information recording step of recording second file information originally identical to the first file information in a second file information table related to the client;
A second system information processing step for obtaining the second file information from the second file information table;
A second authentication key creating step of creating a second authentication key based on the second file information;
The first authentication key created by the arbitrary client is compared with the second authentication key related to the client, and if both are the same, the client system is normal, and if both are not the same A service authentication process for authenticating that the client system is abnormal;
Authentication method. The authentication server includes a random number key creating step for creating a key seed,
In the first authentication key creation step, a first authentication key is created using a one-way function based on the first file information, time, and the key seed related to the client,
Creating a second authentication key using the one-way function based on second file information, time and the key seed associated with the client in the second authentication key creating step;
The authentication method according to claim 5.

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