JP2022119367A - Data processing device - Google Patents

Abstract

An object of the present invention is to prevent an external device from erroneously recognizing a data length.
A communication control unit (181) for extracting content data contained in received packet data received from an external device and transmitting the extracted content data to a conversion device; An acquisition unit 182 that acquires data, a counting unit 183 that counts the data length of the post-conversion data acquired by the acquisition unit 182, and return packet data including the post-conversion data, which indicates the data length of the return packet data. A generation unit 184 that generates return packet data including length information, and an output unit 185 that outputs the return packet data generated by the generation unit 184 to an external device.
[Selection drawing] Fig. 2

Description

The present invention relates to a data processing device that transmits and receives packet data.

Conventionally, there is known a technique of transferring data including a data length identifier indicating data length from a transmission device to a client device (for example, see Patent Document 1).

JP-A-2001-144778

A data processing device that converts data received from an external device by transferring it to a conversion device and transfers the converted data to the external device also has a header that indicates the data length.

However, if the data length changes when the conversion device converts the data, if the header included in the data received from the external device is used as it is, the external device misidentifies the data length. There was a problem.

SUMMARY OF THE INVENTION It is an object of the present invention to provide a data processing apparatus that can prevent an external device from erroneously recognizing the data length.

A data processing apparatus according to a first aspect of the present invention includes a communication control unit for extracting content data contained in received packet data received from an external device and transmitting the extracted content data to a conversion device; an acquisition unit for acquiring post-conversion data after being converted by the conversion device; a counting unit for counting the data length of the post-conversion data acquired by the acquisition unit; and return packet data containing the post-conversion data. a generation unit for generating return packet data including data length information indicating the data length of the return packet data; and an output unit for outputting the return packet data generated by the generation unit to the external device.

The counting unit may count the data length of the post-conversion data acquired by the acquiring unit from the conversion device for each byte. The acquisition unit may acquire the post-conversion data after the content data is converted by the conversion device by encrypting the content data.

ADVANTAGE OF THE INVENTION According to this invention, it is effective in suppressing erroneous recognition of data length by an external device.

It is a figure which shows the outline|summary of the data conversion system of embodiment. It is a figure which shows the structure of a data processor. 4 shows how data is transmitted and received by a communication control unit. FIG. 10 is a sequence diagram showing a procedure of data conversion processing by the data conversion system;

<First Embodiment>
[Overview of data conversion system]
FIG. 1 is a diagram showing an overview of a data conversion system S of this embodiment. A data conversion system S includes a data processing device 100 , an external device 200 and a conversion device 300 . The data processing device 100 is, for example, a computer. The data processing device 100 is connected to an external device 200 and a conversion device 300 . The data processing device 100 relays data transmission/reception between the external device 200 and the conversion device 300 .

The external device 200 and conversion device 300 are, for example, computers. The conversion device 300 converts data received from the external device 200 via the data processing device 100 using a predetermined method. For example, conversion device 300 encrypts the received data.

The data processing device 100 receives received packet data from the external device 200 ((1) in FIG. 1). The data processing device 100 extracts content data included in the received packet data. The data processing device 100 transmits the extracted content data to the conversion device 300 ((2) in FIG. 1). The conversion device 300 converts the received content data to generate post-conversion data. The data processing device 100 acquires post-conversion data from the conversion device 300 ((3) in FIG. 1). The data processing device 100 counts the data length of the acquired post-conversion data. The data processing device 100 generates return packet data including post-conversion data. The data processing device 100 calculates the data length of the return packet data based on the counted data length of the post-conversion data.

The data processing device 100 includes data length information indicating the data length of the return packet data in the header of the return packet data. The data processing device 100 outputs the generated return packet data to the external device 200 ((4) in FIG. 1). In this way, when the data length of the return packet data is different from the data length of the original received packet data, the data processing device 100 sets the data length of the original received packet data to the data length of the return packet data. erroneous recognition can be suppressed.

[Configuration of conversion device]
FIG. 2 is a diagram showing the configuration of the data processing device 100. As shown in FIG. The data processing device 100 includes a communication section 11 , a network adapter 12 , a signal conversion circuit 13 , a signal conversion circuit 14 , a connector 15 , a connector 16 , a storage section 17 and a control section 18 .

The communication unit 11 is a communication interface that communicates with the external device 200 via a network such as a LAN (Local Area Network). The communication unit 11 may communicate with a plurality of external devices 200 . In the example of FIG. 2 , the communication section 11 communicates with the external device 200 via the network adapter 12 . The network adapter 12 is, for example, a LAN adapter.

A signal conversion circuit 13 converts a single-ended signal into a differential signal. A single-ended signal is a signal whose high level and low level are determined by the voltage level of the signal. A differential signal is a signal whose high level and low level are determined by the potential difference between two signals. The signal conversion circuit 13 extracts data input to a transmission buffer (not shown) by the control unit 18 by a FIFO (First In, First Out) method, and converts a single-ended signal corresponding to the extracted data into a differential signal. The signal conversion circuit 13 transmits the converted differential signal to the conversion device 300 via the connector 15 .

Signal conversion circuit 14 receives differential signals from conversion device 300 via connector 16 . For example, the signal conversion circuit 14 receives the differential signal from the conversion device 300 byte by byte. The signal conversion circuit 14 inputs an interrupt signal to the control unit 18 each time it receives one byte of the differential signal. The signal conversion circuit 14 converts the received differential signal into a single-ended signal. The signal conversion circuit 14 inputs data indicated by the converted single-ended signal to a reception buffer (not shown). Signal cables are connected to the connectors 15 and 16 . For example, the connectors 15 and 16 are connected with signal cables of a differential signaling system.

The storage unit 17 is a storage medium such as ROM (Read Only Memory) and RAM (Random Access Memory). The storage unit 17 stores programs executed by the control unit 18 . The control unit 18 is, for example, a CPU (Central Processing Unit). Also, the control unit 18 may be an FPGA (field-programmable gate array). The control unit 18 functions as a communication control unit 181 , an acquisition unit 182 , a counting unit 183 , a generation unit 184 and an output unit 185 by executing programs stored in the storage unit 17 .

The communication control unit 181 communicates with the external device 200 via the communication unit 11 and network adapter 12 . The communication control unit 181 communicates with the conversion device 300 via the signal conversion circuit 13 and connector 15 .

The communication control unit 181 receives received packet data from the external device 200 . The received packet data is IP packet data for TCP/IP communication, for example. The communication control unit 181 extracts content data included in the received packet data. The communication control unit 181 transmits the extracted content data to the conversion device 300 . In the example of FIG. 2 , the communication control unit 181 transmits the content data to the conversion device 300 by inputting the content data into the transmission buffer that stores the data to be transmitted to the conversion device 300 .

3A and 3B show how data is transmitted and received by the data processing device 100. FIG. 3A shows how the communication control unit 181 transmits the content data included in the received packet data to the conversion device 300. FIG. FIG. 3B shows how the generator 184 generates return packet data.

The left side of FIG. 3A shows received packet data received by the communication control unit 181 from the external device 200 . The received packet data includes a header portion, a data portion and an end portion. The header portion includes, for example, data length information indicating the data length of received packet data. The end portion contains an end code indicating where the data portion ends. The communication control unit 181 extracts content data contained in the data portion of the received packet data, as shown in the center of FIG. 3(a). The communication control unit 181 transmits the extracted content data to the conversion device 300 . The content data transmitted from the communication control unit 181 to the conversion device 300 is converted by the conversion device 300 (right side of FIG. 3(a)).

The acquisition unit 182 acquires post-conversion data after the content data has been converted by the conversion device 300 . The acquisition unit 182 acquires post-conversion data for each byte. In the example of this specification, the acquisition unit 182 acquires post-conversion data after conversion by the conversion device 300 by encrypting the content data. It is assumed that the acquisition unit 182 acquires post-conversion data that the signal conversion circuit 14 has input to the reception buffer. The acquiring unit 182 outputs the acquired post-conversion data to the counting unit 183 and the generating unit 184 .

The counting unit 183 counts the data length of the post-conversion data acquired by the acquiring unit 182 . More specifically, the counting unit 183 counts the data length of the post-conversion data acquired by the acquiring unit 182 for each byte. More specifically, the counting unit 183 counts the data length of the post-conversion data by counting the number of bytes of the post-conversion data stored in the reception buffer. An interrupt signal may be input from the signal conversion circuit 14 to the counting unit 183 each time the obtaining unit 182 obtains 1 byte of post-conversion data converted from a differential signal to a single-ended signal in the signal conversion circuit 14 . . The counting unit 183 may count the data length of the post-conversion data by counting the number of times the interrupt signal is input. The counting unit 183 notifies the generation unit 184 of the counted data length of the post-conversion data.

[Generation of return packet data]
The generation unit 184 generates return packet data including post-conversion data. The returned packet data is, for example, IP packet data for TCP/IP communication. The generation unit 184 includes data length information indicating the data length of the return packet data in the return packet data.

The left side of FIG. 3B shows an example of return packet data generated by the generator 184 . Return packet data includes a header portion, a data portion and an end portion. The generating unit 184 calculates the data length of the return packet data based on the data length of the post-conversion data counted by the counting unit 183 . The generation unit 184 generates the header portion of the return packet data by duplicating the header portion of the received packet data acquired by the acquisition unit 182 . The generation unit 184 deletes the original data length information indicating the data length of the received packet data from the returned packet data, and includes new data length information indicating the calculated data length of the returned packet data in the header portion.

The generation unit 184 stores the post-conversion data acquired by the acquisition unit 182 (the center of FIG. 3B) in the data portion of the return packet data. The generation unit 184 generates the end portion of the return packet data by duplicating the end portion of the received packet data.

The output unit 185 communicates with the external device 200 via the communication unit 11 and network adapter 12 . The output unit 185 outputs the return packet data generated by the generation unit to the external device 200 .

[Data Conversion Processing Procedure by Data Conversion System]
FIG. 4 is a sequence diagram showing the procedure of data conversion by the data conversion system S. As shown in FIG. The processing procedure in FIG. 4 starts, for example, when the external device 200 receives an administrator's operation instructing transmission of packet data to the data processing device 100 .

First, the communication control unit 181 of the data processing device 100 receives received packet data from the external device 200 . The communication control unit 181 extracts content data from the data portion of the received packet data. The communication control unit 181 transmits the extracted content data to the conversion device 300 . The conversion device 300 converts the received content data to generate post-conversion data (S11). The acquisition unit 182 of the data processing device 100 acquires post-conversion data from the conversion device 300 . The counting unit 183 counts the data length of the converted data acquired by the acquiring unit 182 (S12).

The generator 184 generates return packet data including the post-conversion data (S13). The generation unit 184 includes data length information indicating the data length of the return packet data in the return packet data. The output unit 185 outputs the return packet data generated by the generation unit 184 to the external device 200 .

[Effects of the data processing device of the first embodiment]
The generation unit 184 includes data length information indicating the data length of the return packet data in the return packet data. In this way, the generator 184 prevents the external device 200 from mistaking the data length of the received packet data as the data length of the returned packet data when the data length changes when the conversion device 300 converts the content data. Recognition can be restrained.

When the administrator tests whether the data processing apparatus 100 according to the first embodiment correctly creates the data length information of the return packet data, the case where the amount of decrease in the data length of the received packet data is the maximum value, It suffices to test three cases: a case in which the amount of increase in the data length of the received packet data is the maximum value, and a case in which the amount of increase or decrease in the data length of the received packet data is smaller than the maximum value. Therefore, the data processor 100 can make the workload of the administrator who tests the data processor 100 relatively small.

<Second embodiment>
In the first embodiment, an example in which the counting unit 183 of the data processing device 100 counts the data length of post-conversion data has been described. On the other hand, in the second embodiment, an example in which the external device 200 estimates the data length of post-conversion data before conversion will be described.

The amount of increase or decrease in data length during data conversion by the conversion device 300 is determined by the types and number of various commands included in the data portion of the received packet data. In the storage unit (not shown) of the external device 200, the conversion device 300 converts a combination of a plurality of commands that may be included as the content data of the received packet data, and the content data including these combinations. An increase/decrease table is stored that associates the amount of increase or decrease with which the data length of the content data changes.

The external device 200 identifies all commands included in the content data of the received packet data before transmission to the data processing device 100 . The external device 200 refers to the increase/decrease table stored in the storage unit, and specifies the amount of increase or decrease in the data length associated with the combination of commands matching the specified combination of commands in the increase/decrease table.

The external device 200 generates post-conversion data length information indicating the amount of increase or decrease in the identified data length. The external device 200 includes the pre-conversion data length information indicating the data length of the reception packet data and the generated post-conversion data length information in the header portion of the reception packet data.

After the conversion device 300 converts the content data of the received packet data, the generation unit 184 of the data processing device 100 duplicates the header section including the pre-conversion data length information and the post-conversion data length information to generate the return packet data. Generate the header part of In this way, the external device 200 can grasp the data length of the return packet data by referring to both the pre-conversion data length information and the post-conversion data length information included in the header of the return packet data. .

Although the present invention has been described above using the embodiments, the technical scope of the present invention is not limited to the scope described in the above embodiments, and various modifications and changes are possible within the scope of the gist thereof. be. For example, all or part of the device can be functionally or physically distributed and integrated in arbitrary units. In addition, new embodiments resulting from arbitrary combinations of multiple embodiments are also included in the embodiments of the present invention. The effect of the new embodiment caused by the combination has the effect of the original embodiment.

11 communication unit 12 network adapter 13 signal conversion circuit 14 signal conversion circuit 15 connector 16 connector 17 storage unit 18 control unit 100 data processing device 181 communication control unit 182 acquisition unit 183 counting unit 184 generation unit 185 output unit 200 external device 300 conversion device

Claims (3)

a communication control unit for extracting content data contained in received packet data received from an external device and transmitting the extracted content data to the conversion device;
an acquisition unit that acquires post-conversion data after the content data has been converted by the conversion device;
a counting unit that counts the data length of the post-conversion data acquired by the acquiring unit;
a generator for generating return packet data including the post-conversion data, the return packet data including data length information indicating the data length of the return packet data;
an output unit that outputs the return packet data generated by the generation unit to the external device;
A data processing device comprising: The counting unit counts the data length of the post-conversion data acquired by the acquisition unit from the conversion device for each byte,
2. A data processing apparatus according to claim 1. The acquisition unit acquires the post-conversion data after the content data is converted by the conversion device by encrypting it.
3. A data processing apparatus according to claim 1 or 2.

Images