JP2768474B2 - Certification system - Google Patents

Description

The present invention relates to a credential authentication system using an encryption key,
In particular, qualification authentication is performed by transmitting and receiving signals between the data communication devices, transmitting encryption information from one (second) data communication device, and receiving and decrypting the encrypted information with the other (first) data communication device. The present invention relates to a qualification authentication system using a communication line.

[Conventional technology and problems to be solved by the invention]

Recently, a database system and the like have been proposed and implemented in which a terminal device such as a personal computer is connected to a host computer via a communication line, and information is transmitted and received between the terminal device and the host computer. For example, a farm banking system, a home banking system, a home trade system, and the like, in which a modem (MODEM) is connected to a personal computer installed in an office or home and connected to a host computer of a bank or securities company via a public line, have been implemented. ing. In addition, a system for connecting to various databases through a communication line and searching for information online has been implemented.

In these conventional systems, when a user accesses a host computer from each terminal device, the user inputs a code or password peculiar to the individual from the terminal device, transmits the code to the host computer, and transmits the code or password to the host computer. It is checked whether the user of the terminal device has the access qualification.

However, with the conventional qualification confirmation system, there is a risk that these codes and passwords can be eavesdropped on the communication line. If eavesdropped, they can be stolen by a third party and illegally access the host computer. However, there is a problem that the information of the personal host computer is misused.

In order to solve such problems, a method has been proposed in which personal codes and passwords are encrypted at the terminal device and sent to the host computer. However, even if the encrypted key is decrypted, it can be accessed by stealing it There is a problem that is.

There is also a system that uses fingerprint information to confirm an individual, but this system itself has the problem that fingerprint information can be eavesdropped on a communication line and can be stolen as it is. is there.

SUMMARY OF THE INVENTION An object of the present invention is to solve the above-mentioned problems, and to provide a new communication method in which a third party cannot access this data communication apparatus even if a signal is eavesdropped on a communication line between the data communication apparatuses. To provide a secure personal qualification authentication system.

[Means for solving the problem and operation]

FIG. 1 shows the basic configuration of the qualification authentication system of the present invention.

In the figure, the qualification authentication system has a communication unit 14 and a communication unit 26, respectively, and the communication unit 14 and the communication unit 26 are connected via a communication line 30, and are configured to be communicable with each other. A data communication device 10 and a second data communication device 20 are provided.

The first data communication device 10 includes a personal code input unit 11 for inputting a personal code CODEA, a secret key input unit 12 for inputting a secret key, and a decryption unit 13.

The second data communication device 20 includes the first data communication device 10
Secret key search means 21 for retrieving a pre-registered corresponding secret key CODX corresponding to the personal code transmitted from, random number generating means 22 for generating a random number R1 each time a personal code is received, and extracting the random number Encryption means 24 for encrypting with a secret key, and comparison / comparison means 25.

The decryption means 13 decrypts the data SR encrypted by the encryption means 24 with the secret key input by the secret key input means 12. The comparison / matching unit 25 compares and matches the random number R1 generated by the random number generation unit 22 with the random number R1 ′ decrypted by the decryption unit 13, and accesses the first data communication device 10 if they match. Sends a permission signal.

With this configuration, in addition to the personal code, a secret key is used, and the secret code and a random number generated each time are combined and encrypted. Therefore, personal authentication with high security can be performed.

Preferably, the secret key input from the secret key input means 12 is a user's fingerprint, and the secret key search means 21 extracts a corresponding pre-registered fingerprint secret key, and Is encrypted by the fingerprint secret key, and the decryption means 13 decrypts the data encrypted by the encryption means 24 based on the fingerprint secret key.

By using the fingerprint unique to the user, the security strength in communication is further improved.

Further, the personal code input means and the secret key input means can be constituted by a common input means.

〔Example〕

A first embodiment of a qualification authentication system according to the present invention will be described with reference to FIGS.

FIG. 2 is a configuration block diagram of the present embodiment. In FIG. 1, reference numeral 100 denotes one of a plurality of terminal devices individually provided in a home or an office, which is constituted by a microcomputer system. The terminal device includes a microprocessor unit for performing various control and arithmetic operations for decoding. (ΜPU) 11
1. ROM 113 for storing a control program, RAM 114 for storing various data, a modem interface 116 and a modem 117 for transmitting and receiving data via a communication line 300 with a host computer 200 described later, and a personal computer (PC) 400 An input / output interface 115 for coupling with the μPU 111;
It is composed of a CPU bus 112. Reference numeral 200 denotes a host computer. The host computer includes a CPU 221 for performing various controls, calculations for encryption and collation, a ROM 223 for storing various control programs, and a RAM 224 for temporarily storing data.
, A magnetic disk device 228 storing a registered secret code, a disk interface 226, and a plurality of terminal devices, for example, a modem connected to the terminal device 100 via the communication line 300 to transmit and receive data. 227, and
And a modem interface 225. Three
00 indicates a communication line such as a public line or a specific communication line. 400
Indicates a personal computer coupled to the terminal device 100, and includes an input device (not shown) such as a keyboard and a display device such as a CRT.

Here, when associating with the configuration of FIG. 1, the first data communication device 10 is the terminal device 100 and the personal computer 400, the communication line 30 is the communication line 300, and the second data communication device 20
Is realized by the host computer 200. Furthermore,
The personal code input means 11 or the secret key input means 12 includes a personal computer 400, an I / O interface 115, a μPU 111, a ROM 113
It is realized by the program in. The decoding means 13 calculates μ
This is realized by the PU 111, the program in the ROM 113, and the RAM 114. Communication means 14 includes μPU 111, modem interface 1
16, realized by the modem 117. On the other hand, the communication means 26
Is realized by a CPU 221, a modem 227, and a modem interface 225. The secret key search means 21 includes a CPU 221 and a ROM 2
23 programs, magnetic disk interface 22
6. This is realized by the magnetic disk device 228. The random number generation means 22 is realized by the CPU 221, a program in the ROM 223, and the RAM 224. The encryption means 24 is realized by a program in the CPU 221 and the ROM 223, and the RAM 224. The comparison and matching means 25
This is realized by the CPU 221, the program in the ROM 223, and the RAM 224.

Hereinafter, the functions and operations of each unit of the personal qualification authentication system according to the first embodiment of the present invention will be described based on the embodiments shown in FIGS. FIG. 3 shows an operation form diagram, and FIG. 4 shows a flowchart.

An individual who has a qualification to access the host computer 200, that is, a user of the qualification authentication system, registers his / her own secret code together with his / her personal code in the magnetic disk device 228 in the host computer 200 in advance (S001). ). The personal code is, for example, a code which is disclosed by a member number or the like assigned to each individual and has no special problem even if wiretapped. A secret code is a code known only to that individual. A user who wants to access the host computer 200 first inputs his / her personal code CODEA on the keyboard of the personal computer 400 connected to the terminal device 100 (S002). The personal code CODEA is composed of, for example, alphanumeric characters. The personal code CODEA input to the personal computer 400 is input to the terminal device 100, and the
Host computer 20 via communication line 300 via 117
It is transmitted to 0 (S003). The host computer 200 receives the personal code CODEA from the modem 227 and receives the received personal code.
The personal secret code CODEX corresponding to CODEA is read from the magnetic disk device 228 (S004). Secret code CODEX
Is composed of, for example, alphanumeric characters. At the same time, each time the personal code is received, the CPU 221 runs a random number generation program built in the ROM 223 to generate a random number (S005). This random number is, for example, 64 bits long. R1
And These generated random numbers R1 are temporarily stored in the RAM 224. Next, the CPU 221 encrypts the generated random number R1 using the secret code CODEX obtained based on the personal code CODEA (S006, S007).

The encryption method will be described below. Secret code CODEX
Corresponds to each alphanumeric character, for example, 8
It is converted into a binary number of bits to obtain a secret key XK. The secret code CODEX is configured in advance so that it becomes 64 bits when converted to the secret key XK. Next, the random number R1 is
Using XK, for example, the well-known DES (Date Encryption S
tandard), and is encrypted by the CPU 221 (S00
7).

The random number SR encrypted with the secret key XK is transmitted to the modem 227
Via the communication line 300 to the terminal device 100 (S008). The terminal device 100 receives the random number SR encrypted by the modem 117 and stores the random number SR in the RAM 114. The user who intends to access next inputs the same secret code CODEX ′ as the one registered in the magnetic disk device 228 from the keyboard of the personal computer 400 and known only to the user (S009). The input secret code CODEX ′ is transmitted to the terminal device 1 as described above.
In step S010, the terminal device 100 uses the secret key XK 'to decode the received encrypted random number SR to obtain a random number R1' (S011). ).
The decoding method is performed by, for example, the DES method as described above. Therefore, in the terminal device 100, a random number R1 'equivalent to the random number R1 generated by the host computer 200 can be obtained. Next, the terminal device 100 transmits the decrypted random number R1 ′ to the modem 11
7, and the host computer 200 via the communication line 300
(S012).

The host computer 200 receives the random number R1 decrypted by the modem 227, and compares the received random number R1 'with the random number R1 stored in the RAM 224. Here, these random numbers R1 and R
If 1 'matches, the host computer 200 becomes accessible to the terminal device 100 and sends an access permission signal to the terminal device 100. After that, the user
It becomes accessible.

In the qualification authentication system described above, the terminal device 10
Since the data transmitted from 0 through the communication line 300 is a public code CODEA or a random number R1 generated for each access, even if the data is eavesdropped on the communication line 300, the information is used. Even host computer
It is impossible to access 200. Also, the random number SR encrypted with the secret key XK transmitted from the host computer 200 to the terminal device 100 and the random number transmitted from the terminal device 100 to the host computer 200 on the communication line 300
Even if both R1's are eavesdropped, the former random number is encrypted by the DES method, so the cryptographic strength is guaranteed,
It is impossible to decrypt the encryption key using both.

In this embodiment, the case has been described where the user inputs the personal code CODEA and the secret code CODEX separately and independently, but these codes may be input collectively. In this case, the secret code CODEX may be temporarily stored in the RAM 114.

Next, as a second embodiment, using information peculiar to an individual, for example, a fingerprint, which has a higher degree of security, that is, even if a secret code is stolen by eavesdropping on operations, it cannot be accessed by a third party. Describe the credential authentication system. FIG. 5 is a block diagram showing the configuration of the second embodiment.

In the qualification authentication system shown in FIG. 5, a fingerprint input device 500 is connected to a terminal device 100 '. The configurations of the terminal device 100 ', the host computer 200', and the personal computer 400 'are the same as those of the first embodiment described with reference to FIG. 3, but their functions are different as described below.

Hereinafter, the functions and operations of the qualification authentication system according to the second embodiment of the present invention will be described based on the embodiments shown in FIGS.

An individual who has a qualification to access the host computer 200 'registers its secret code CODEX and fingerprint information F together with its own personal code CODEA in the magnetic disk device 228' of the host computer 200 'in advance. The personal code CODEA and the secret code CODEX are the same as in the first embodiment. For example, the fingerprint information F can be obtained from a “ridge pattern detecting device of ridge pattern (Japanese Patent Application No. 62-14) filed earlier by the present applicant.
No. 4012), the direction of the ridge pattern of the fingerprint is coded and stored.

Also in the second embodiment, the processing of steps S001 to S011 shown in the flowchart of FIG. 4 is performed.

In step S011, after the decoded random number R1 'is obtained,
The following processing is performed.

An individual who wants to access inputs his / her own fingerprint as fingerprint information from a fingerprint input device 500 including a CCD camera or the like. As described in detail in the aforementioned Japanese Patent Application No. 62-144012, the input fingerprint information is divided into, for example, 32 × 32 unit areas, and the ridge direction of the fingerprint is calculated for each unit area. , Are stored as direction codes. Next, the terminal device 10
0 'encrypts the fingerprint information by the DES method using the decrypted random number R1' as a secret key. The method will be described below.

The random number R1 'used as the secret key is 2 as described above.
It is 64 bits in hexadecimal. The fingerprint information has a 32 × 32 area, that is, 1024 directions and codes, and if the direction codes are 1 to 8, the one-way code is represented by 4 bits including address information, and is therefore represented by 4096 bits. Next, the fingerprint information is divided into 64 bits, and each is encrypted by the DES method using the random number R1 'as a secret key.

Then, the encrypted fingerprint information SF is transmitted to the host computer 200 'via the communication line 300. The host computer 200 'decodes the encrypted fingerprint information SF using the random number R1 stored in the RAM 224, and obtains the fingerprint information F. Next, the host computer 200 'reads the fingerprint information F corresponding to the personal code CODEA from the magnetic disk device 228', and compares it with the fingerprint information F obtained by decoding. Here, if the fingerprint information matches, the host computer 200 'determines that the user operating the terminal device 100' is a qualified person, and the user can access the terminal device 100 '. Then, an access permission signal is sent to the terminal device 100 '.

In the qualification authentication system described above, the communication line 30
Since the data transmitted via 0 is an encrypted personal information or information encrypted by a random number generated on the host side for each access, it is tentatively eavesdropped on the communication line 300 by a third party. Even so, it is impossible for a third party to illegally access the host computer using the information.

In the second embodiment, the host computer 200 'compares the fingerprint information encrypted with the random number sent from the terminal device 100' with the random number first, and then compares and compares the fingerprint information with the pre-registered fingerprint information. I did authentication,
First, the terminal device 100 'encrypts a random number with fingerprint information, and the host computer 200' preliminarily encrypts the magnetic disk device 228 '.
May be compared using random numbers decrypted with the fingerprint information registered in. In this case, the fingerprint information obtained by compressing the feature information is configured as 64 bits, and the random number is configured as 64 bits.

Furthermore, when the fingerprint information is finally compared and collated as in the second embodiment, a margin may be provided to some extent so that the user is authenticated when the probability that the fingerprint information matches is 60%, for example.

As described above, the example in which the fingerprint information is used for personal qualification authentication has been described in the second embodiment, but the fingerprint direction code may be used as the secret code in the first embodiment.

Further, in the above embodiment, the terminal device and the personal computer are provided independently and connected to each other. However, they may be integrated.

Further, in the above-described embodiment, the case where the terminal device and the host computer are used has been described. However, the terminal device stores the secret key search means, the encryption means, the random number generation means, and the secret code in the same manner as the host computer. A unit may be added to authenticate a qualification in communication between terminal devices.

〔The invention's effect〕

According to the present invention, when certifying the qualification of an individual who accesses an information transmitting / receiving system using a communication line, even if the communication information is eavesdropped on the communication line, illegal access by a third party is prevented. Can be prevented.

[Brief description of the drawings]

FIG. 1 is a basic configuration diagram of a qualification authentication system of the present invention, FIG. 2 is a configuration diagram of a qualification authentication system of a first embodiment of the present invention, FIG. 3 is an operation form diagram of the qualification authentication system of FIG. FIG. 4 is a flowchart of the qualification authentication system of FIG. 2, FIG. 5 is a configuration diagram of the qualification authentication system of the second embodiment of the present invention, and FIG. 6 is an operation form diagram of the qualification authentication system of FIG. ,. (Explanation of symbols) 10 first data communication device 11 personal code input device 12 secret key input device 13 decoding device 14 communication device 20 second Data communication device, 21 secret key search means, 22 random number generation means, 24 encryption means, 25 comparison comparison means, 26 communication means, 30 communication line, 100 terminal equipment , 200: Host computer, 300: Communication line, 400: Personal computer, 500: Fingerprint input device.

 ──────────────────────────────────────────────────続 き Continuation of the front page (56) References JP-A-2-44389 (JP, A) JP-A-63-248246 (JP, A) JP-A-62-118472 (JP, A) JP-A-63-118 273980 (JP, A) JP-A-1-161938 (JP, A) JP-A-63-223969 (JP, A)

Claims (3)

(57) [Claims] 1. Communication means (14) and communication means (26), respectively.
A first data communication device (10) and a second data communication device (14) and a communication device (26), which are connected via a communication line (30) and configured to be able to communicate with each other. The first data communication device comprises a personal code input means (11) for inputting a personal code (CODEA), a secret key input means (12) for inputting a secret key, and a decoding means. (13), wherein the second data communication device is a secret key search means (21) for extracting a pre-registered corresponding secret key (CODEX) corresponding to the personal code transmitted from the first data communication device. When,
Random number generating means (22) for generating a random number (R1) each time a personal code is received, encrypting means (24) for encrypting the random number with the secret key taken out, and comparing and collating means (25)
The decryption means decrypts the data (SR) encrypted by the encryption means with the secret key input by the secret key input means, and the comparison / matching means comprises the random number generation means The random number (R1) generated in (1) and the random number (R1 ′) decoded by the decoding means are compared and collated, and if they match, an access permission signal is sent to the first data communication device. Credential authentication system. 2. The secret key input from the secret key input means is a user's fingerprint. The secret key search means retrieves a corresponding pre-registered fingerprint secret key, and the encrypting means extracts the fingerprint secret key. 2. The qualification authentication system according to claim 1, wherein the data is encrypted by a key, and the decryption means decrypts the data encrypted by the encryption means based on the fingerprint secret key. 3. The personal code input means and the secret key input means are constituted by a common input means.
Or the qualification authentication system according to 2.