JPS63103533A - Cryptographic communication processing system - Google Patents

Abstract

PURPOSE:To improve the reliability, maintenability and operability of the system and equipment by containing the function required for cryptographic communication processing into an IC card, and providing an IC card interface to a data input/output device so as to eliminate the need for an independent cryptographic communication equipment and a cryptographic key input device. CONSTITUTION:The function such as an arithmetic processing processor 22 and a key data logic circuit 23 required for cryptographic communication processing is mounted in an IC card 15 and constituted so as to be connected logically to a conventional terminal equipment and a communication control circuit 16 of a data input/ output device 11 via an IC card interface circuit 34. Thus, the cryptographic communication processing IC card 15 is inserted to a conventional data input/output device or terminal equipment or the like and cryptographic text communication with high reliability is attained through a simple operation. Moreover, the independency of the cryptographic communication processing function is assured by the IC card mounting an electronic circuit including a microcomputer and a memory or the like in such a way, the device is miniaturized and the weight is lightened, the portable and movable cryptographic text communication is attained and the reliability, operability and efficiency are improved.

Description

[Detailed Description of the Invention] [Industrial Field of Application] The present invention is applicable to security protection used for communication of data, messages, images, etc. in, for example, teletex, personal computer communication, office automation, and similar information communication systems. The present invention relates to a cryptographic communication processing system.

[Conventional technology]

Hitherto, encrypted communication processing systems have been put to practical use as a means for realizing confidentiality or privacy protection for data and messages exchanged between terminal devices and computers in information communication systems or networks.

In this case, an independent cryptographic communication device is installed between the data input/output device in the terminal and the line, and in the case of ciphertext mode, all the necessary communication processing is performed between the data input/output device and the logic circuit of the cryptographic communication device and the This depended on the control program.

Figure 3 shows, for example, the conventional encrypted communication processing system shown in 1 Co/Computer Security 1 (Kinda Kagakusha; published in 1981). FIG.

In the figure, 11 data input/output devices, 12 a line adapter device for making all line connections, 13 a cryptographic communication device installed between the data input/output device 11 and the line adapter device 12, and 14 a computer code. This is a cryptographic key manual device connected to the communication device 13. Further, 20 is a central processing unit as a communication control processor that controls communication of plaintext or ciphertext using a microprocessor, 21 is a storage circuit that stores communication control programs and data, and 22 is a central processing unit that processes plaintext to be transmitted by a certain algorithm. An arithmetic processing processor 23 that performs arithmetic processing when converting received ciphertext into plaintext; and 23 is a key data that becomes a parameter of a processing program for this arithmetic processing processor 22. 24 is a register for temporarily storing ciphertext or plaintext; 25 is a line interface circuit that connects the communication control circuit and the line adapter device 12 to exchange data; and 26 is a data input/output device. 11, 27u an internal bus serving as an information transmission path connecting the bus interface circuit 26 and each of the circuit devices, 28 and 29 a bypass for mode switching; Switch and key set mode switch, 3o is a key lock key, the cryptographic communication device 13
is composed of these.

Next, the operation will be explained. FIG. 4 is a flowchart showing the operation. First, the operation and device operation procedure when the encrypted communication device 13 is connected to the data input device 11 and ciphertext or plaintext is transmitted to the other party's data center through the line. 0 When the bypass switch 28 and the keyset mode switch 29 of the cryptographic communication device 13 are OFF, that is, when the bypass switch 28 and the keyset mode 0 switch 29 are closed with the P pole, the cryptographic mode is activated. It is. The operator who sends the cipher text is the bypass switch 2.
8 and key set mode switch 29 to the -P pole position (step 5T1), data input/output device 11
By setting the transmission key eON, the plaintext data stored in the buffer memory of the data input/output device 11 is transferred to the cryptographic communication device 13 (step 5T4). The transferred plaintext data is transferred to the arithmetic processing processor 22 which performs encryption and decryption processing based on the encryption key set in the key data logic circuit 23 and a certain encryption algorithm under the control of the central processing unit [20]. is converted to ciphertext by
Send the encrypted data to the line via the register 24 and the line interface circuit 25ft (step 5T)
5).

When the transmission of the encrypted data is completed (step 5T6),
The program of the central processing unit 20 performs termination processing and ends the ciphertext transmission operation (Stella: 7'5T7). The key data logic circuit 23 in the ciphertext transmission operation includes parameters for controlling ciphertext conversion by the cryptographic algorithm;
A removable memory that provides a "key" and allows the administrator to change the contents as needed? I have it.

Also, an arithmetic processing processor 2 that performs encryption and decryption processing.
2 is an algorithm that sequentially encodes and decrypts constituent units of plaintext using a cryptographic dictionary, fc9, and repeatedly performs substitution, arithmetic processing, and order control for each fixed length of plaintext. Read-only memory (read-only memory: R)
OM), and control/processing logic circuits. In this case, the contents of the cryptographic key and the cryptographic algorithm, and the processing operations will not be explained because they have no direct relation to non-invention.

Next, the operation and operating procedure of the device when transmitting plain text will be explained. Bypass switch 28 of cryptographic communication device 13
is ON, key set mode switch 29 is OFF
F, that is, bypass switch 28 is q
The plain text mode is when the key set mode switch 29 is closed at the P pole. In step ST1, the operator transmitting the plain text sets the bypass mode switch 28 and the key set mode switch 29 to the centipede position.
, 5T8), data input/output device ↑ Sae 11 transmission key eON
By setting the buffer of the data input/output device 11,
The plaintext data stored in the memory is transferred to the cryptographic communication device 13 (step ST11), bypassing its cryptographic communication function, and directly transmitted from the line interface circuit 25 to the line via the line adapter device 12 (step ST12). ).

In this case, data? Operators of mutual terminals communicating with each other need to set or switch the transmission/reception mode prior to data transmission by communicating with the data center or directly with the other party's terminal using other communication means. Transmission of plaintext data in the plaintext transmission mode is performed in this manner, and when the transmission is completed, the central processing unit 20 performs termination processing (step 5T14) and ends the plaintext transmission operation.

Next, the encryption key human input fi114f: encryption communication device 13
When the system is started, the encryption key f: is set in the data logic circuit 23, and its contents? The operation in the key set mode used when changing the key set mode and the operating procedure of the device will be explained.

The bypass fist switch 28 is closed to the q pole, the key set mode switch 29 is closed to the r pole on the key manual device 14 side (steps ST8 and ST15), and the key lock key 3 is closed.
0 e OFF (step 5T16). After turning the key lock key 30 t OFF, operate the connected key power device 14 to input the specified key (encryption, decryption key,
After setting the parameters (step ST17), the key manual device 14 is disconnected (step ST18), and the key lock key 30 is turned on (step ST19).

This key lock key 30 is normally operated and stored by a system administrator, and general operators cannot be involved.

[Problem that the invention seeks to solve]

Since the conventional cryptographic communication processing system is configured as described above, the arithmetic processing processor 22, key data logic circuit 23, and register 24, which are the main parts of the cryptographic communication processing function, control them and transfer data. Since the encrypted communication device 13 is configured to be mixedly integrated with common functional parts, the device becomes larger and it is necessary to install an encrypted communication device 13 independent of each data input/output device 11. However, not only is there a problem in terms of system reliability, maintenance, and cost, but there is also a need to switch the transmission mode.

When inputting or changing the encryption key, there are problems such as complicated manual operations and the possibility of erroneous operations. This invention was made to solve the above-mentioned problems, and aims to improve system reliability and maintainability, reduce costs, and realize plaintext and ciphertext communication with simple operations. The purpose is to obtain a cryptographic communication processing system that can perform

[Means for solving problems]

The encrypted communication processing system according to the present invention incorporates functions such as a key data logic circuit necessary for encrypted communication processing such as confidential data, an arithmetic processing processor for encryption and decryption, etc. into an IC card, and uses this IC card as an IC card. By inserting the IC card into a data input/output device, etc. having a Turf Ace, the IC card is driven and performs encryption and decryption communication processing, as well as key data in the IC card inserted directly using the keyboard of the data input device. It inputs and changes the encryption key into the logic circuit.

[Effect]

The cryptographic communication processing system according to the present invention eliminates the need for an independent cryptographic communication device or cryptographic key manual device by converting the functions necessary for cryptographic communication processing into an IC card and providing the data input/output device with an IC card interface. In addition to improving the reliability, maintainability, and operability of systems and equipment, this IC card also registers, verifies, and confirms data as the administrator's personal card, and records information such as when, what kind of data was sent and received, and where. You can also keep records, this I
The C-card also allows for portable and portable encrypted correspondence.

〔Example〕

An embodiment of the present invention will now be described with reference to the drawings. 1st
In the figure, 11, 12, 20 to 25 degrees, 27 and 30 correspond to the conventional ones with the same reference numerals as in FIG. 3, so detailed explanation will be omitted. In addition, 15 is an encrypted communication processing IC card (
16 and 17 are a communication control circuit and a main control circuit of the data input/output device 11 (hereinafter abbreviated as an IC card).

The IC card 15 includes an arithmetic processing processor 22, a key data logic circuit 23, a register 24, and certain encryption,
A storage circuit 31 is installed, which includes a read-only memory containing a program for executing a decoding algorithm, various data tables, a buffer memory, and the like. Further, the communication control circuit 16 of the data input/output device 11 includes a communication control processor 20, a memory circuit 21, and a line interface circuit 25, and the main control circuit 1T is a main control circuit of the data input/output device 11 with a microprocessor. It includes a processor 32 and a storage circuit 33 for storing control programs and data for the data input/output device 11, and a functional part 16 of the communication control circuit and a functional part 17 of the main control circuit.
Each circuit device is connected to an internal bus 27.

This data input/output device 11 further includes an IC card 15.
is connected to the communication control circuit 16, and a power supply is connected to the IC card 15.
The IC card interface circuit 34 has a mechanism and logic circuit for supplying clocks, control information, etc. and transmitting and receiving data, and each circuit device and I in the data input/output device 11.
It includes a clock circuit 35 that generates a clock to be supplied to the C card 15, and a display and keyboard mechanism section 36 having a key lock key 30, and each of these circuit devices is also connected to the internal bus 27.

Next, the operation will be explained. FIG. 2 is a flowchart showing the operation. First, the operation and operation in the case where the data input/output device 11 is connected to the line and the entire IC card 15 is used to transmit the encrypted text to the data center will be explained.

When the IC card 15 is inserted into the data input/output device 11 (step 5T20) and the key lock key 30 is ON (
Step ST22) is the ciphertext mode. An operator who wants to send a cipher text inserts an IC card into the device, sets it to send mode, and then turns on the send key of the data input/output device.
to start the communication control circuit 16 of the data input/output device 11.
A command is given to the storage circuit 21 to transfer the plaintext data to be transmitted to the storage circuit 21. Next, the communication control processor 20
The IC card 15 is activated through the C card interface circuit 34, and power, clock, and commands are supplied to the IC card 15, thereby activating the IC card 15 (step ST25).

Next, the arithmetic processing processor 22 in the IC card 15
For example, the arithmetic processing processor 22, key data logic circuit 23, register 24, and storage circuit 31 in the IC card 15 are activated, and if normal operation is possible, the communication control circuit 16 is activated.
'IC card RED' as the status information of the IC card 15.
Transfer Y' (step 5T26). Next, the arithmetic processing processor 22 of the IC card 15 uses the memory circuit 31 to
Registered personal code (operator management code,
number), encryption key, job code, and line interface circuit 25 in the communication control circuit 16.
, and the line adapter 12, the initial information is transmitted to the other party's terminal or data center (step 5T27).

At this time, the initial information is displayed on a liquid crystal display (not shown) on the IC card 15, so that the operator can confirm normal operation.

The other party's terminal or data center inspects and verifies the registered personal code, encryption key, job code, and other related codes, and then returns response confirmation information.

If the communication control circuit 16 in the terminal receives an affirmative response (step ST2.8), it reads out the previously stored plaintext data in the storage circuit 21 according to the program of the communication control processor 20, and reads out the plaintext data stored in the storage circuit 21 and sends it to the IC card interface 34.
The data is transferred to the IC card 15 via. IC card 15
On the side, the plaintext data is received in a register 24 and transferred to the arithmetic processing processor 22. The arithmetic processor 22 encrypts this plaintext based on the encryption key set in the key data logic circuit 23 and a certain algorithm. The encrypted ciphertext data is transferred to the register 24 again, and then transferred to the communication control circuit 16 via the IC card interface 34.

Next, the ciphertext data is sent to the line interface circuit 25.
is transmitted as encrypted data to the line side via (step 5T29). These encrypted data transmission operations are repeated in units of a certain data block, and when the transmission data or message is completed (step 5T30), the program of the communication control processor 20 performs termination processing to terminate the transmission operation (step ST32). ). Also, at this time, as part of the termination process, communication record data such as the sender/receiver of the communication, the type of communication, the date and time, etc. are recorded in the storage circuit 31 of the IC card (step 5T31). The details of the encryption key, the encryption and decryption algorithms, and the arithmetic processing operations related to the encrypted communication process are not directly related to the present invention, so their explanations will be omitted.

Next, the operations and operating procedures for setting the encryption key in the IC card 15 and changing its contents will be explained.

When the IC card 15 is inserted into the data input/output device 11 and the key lock key 30 is OFF (step ST33
) is the key set mode (step 5T34).

An operator or a key manager operates the keyboard of the display and keyboard mechanism section 36 and the communication control processor 20
, the IC card 1 through the IC interface circuit 34
A key set request is made to the arithmetic processing processor 22 of No. 5 (
Step 5T35).

The arithmetic processing processor 22 reads out the personal code and related information registered in the storage circuit 31, and as a result of the verification,
If the input data and the data match, the communication control processor 20
, and through the main control circuit 1T of the data input device 11 and the display section of the keyboard mechanism section 36, the operator or key manager is authorized to set the key (step 5T36). The operator or key manager sets the necessary keys to the key data logic circuit 23 of the engineering C card 15 (step 5T37) through the display and keyboard operation of the keyboard mechanism section 36, and then sets the key lock key 30.
1-ON, and the key set mode operation ends (step 5T38).

Also, if the IC card 15 is not inserted (step 5
T2G), plaintext mode processing is performed (step 5
T39-5T44).

Note that in this embodiment, the power supply to the IC card 15,
The clock shown here is supplied externally, but I
A system may also be used in which the C card 15 has a built-in solar cell or the like, thereby supplying power and clock internally.

Although not specifically mentioned in the above embodiment, even if the mechanical part of the IC card interface circuit 34 that connects the IC card 15 and the data input/output device 11 is of the terminal socket contact type, optical coupling by an optical card, electromagnetic coupling, etc. A non-contact method such as electromagnetic coupling using a method card may also be used, and either method can achieve the same purpose and effect.

〔Effect of the invention〕

As described above, according to the present invention, a cryptographic communication processing system is implemented in which the functions such as an arithmetic processing processor and a key data logic circuit required for cryptographic communication processing are mounted in an IC card, and are normally connected via an IC card interface circuit. Because it is configured to be logically connected to the communication control circuit of the terminal or data input/output device, when transmitting and receiving confidential data or messages using ciphertext communication that encrypts and decrypts them, it is possible to By inserting a cryptographic communication processing IC card with a cryptographic communication processing function into a normal data input/output device or terminal, highly reliable cryptographic communication can be performed with simple operations. , an IC card equipped with an electronic circuit including memory etc. ensures the independence of the encrypted communication processing function, making the device smaller and more quantifiable, making it possible to send encrypted text in a portable and portable manner. Switching between text mode and key set mode, data communication records, and cryptographic key management are facilitated, and the reliability, operability, and efficiency of cryptographic communication devices and systems are improved.

[Brief explanation of the drawing]

Fig. 1 is a block diagram showing an encrypted communication processing system according to an embodiment of the present invention, Fig. 2 is a flowchart showing its operation, Fig. 3 is a block diagram showing a conventional encrypted communication processing system, and Fig. 4 is its operation. It is a flowchart showing the operation. 11 is a data output device, 12 is a line adapter circuit, 1
5 is a cryptographic communication processing IC card, 16 is a communication control circuit, 1
7 is a main control circuit, 20 is a communication control processor, 22 is an arithmetic processing processor, 2'3 is a key data logic circuit, 25
is a line interface circuit, 27 is an internal bus (information transmission line), 34-digit IC card interface circuit, 36
is the display and keyboard mechanism section. In addition, in the figures, the same reference numerals indicate the same or equivalent parts. (2 others)

Claims (1)

[Claims] A communication control circuit that includes a communication control processor that controls communication of plaintext or ciphertext, a line interface circuit that is connected to a line adapter circuit and that exchanges transmitted and received data, a main control circuit, and an encrypted communication processing IC card to be described later. An IC card interface circuit that connects to the control circuit and supplies power, clock, and control information to the encrypted communication processing IC card to send and receive data, and a data input circuit that connects the display and keyboard mechanism section via an information transmission path. an output device, an arithmetic processing processor that performs arithmetic processing for converting plaintext to be transmitted into ciphertext using a certain algorithm, or conversely converting received ciphertext into plaintext; and processing for the arithmetic processing processor. The IC includes a key data logic circuit that provides key data serving as a program parameter, and is inserted into the data input/output device and is connected to the IC.
A cryptographic communication processing system comprising a cryptographic communication processing IC card connected to the communication control circuit by a card interface circuit.