JP7080024B2 - Communication device - Google Patents

Description

The present invention relates to a communication device, and more particularly to a communication device that performs encrypted communication.

In encrypted communication, transmission data is generally encrypted. In the encryption process, a random number generation process for use in the encryption process, an encryption process using various algorithms, and a hash value calculation process for detecting falsification of transmitted data on the communication path are performed.

In addition, for encrypted communication, Hyper Text Transfer Protocol over TLS (FTPS) communication using Secure Sockets Layer (SSL) or Transport Layer Security (TLS) or File Transfer Protocol (FTPS) communication, File Transfer Protocol, File Trans There is SSH File Transfer Protocol (SFTP) communication, Security Copy (SCP) communication, Virtual Private Network (VPN) communication, and the like used. In addition, there are various VPNs according to the OSI layer model in the VPN, L2TP (Layer 2 Tunneling Protocol) or PPTP (Point-to-Point Tunneling Protocol) that performs encrypted communication processing in the second layer, and the third layer. There is an IPsec (Security Architecture for Internet Protocol) that performs encrypted communication processing, or an SSL VPN that performs encrypted communication processing in the fourth layer or higher.

In the above encryption processing, software (S / W) processing using a CPU (Central Processing Unit) is generally performed, but dedicated security processing hardware (H / W) is used to realize high-speed transfer. There is also a communication device equipped with an engine and performing H / W processing. For example, in Patent Document 1, an H / W processing function having a dedicated encryption / decryption processing engine and an encapsulation processing engine is implemented in a NIC (Network Interface Card), and high-speed transfer by SSL VPN is performed. I'm trying.

International Publication No. 2006/093021

As the cryptographic communication processing method of the gateway device having the conventional cryptographic communication function, the transfer speed is improved by using the generally used S / W processing or the H / W engine as in Patent Document 1. There is / W processing.

In the H / W processing of Patent Document 1, the speed reduction when a specific data size and a specific encryption algorithm or the like are combined is not taken into consideration. Further, the H / W engine of Patent Document 1 is customized for a specific encrypted communication such as IPsec, but there is a problem that the processing is slower than the processing of S / W alone depending on the combination of the data size and the encryption algorithm or the like. was there.

Therefore, the present invention has been made to solve the above-mentioned problems, and an object thereof is to be able to improve the transfer performance of encrypted communication.

The communication device according to one aspect of the present invention uses an encrypted communication processing unit that performs encrypted communication of data, an encryption process that encrypts the data as the encryption process of the data, and a random number used for encrypting the data. The security function unit includes a security function unit that performs a random number generation process for generating and a hash value calculation process for calculating a hash value for detecting falsification of the encrypted data, and the security function unit uses software. The encryption process, the random number generation process, and the hash value calculation process of the data are performed by using the software security function unit that performs the encryption process, the random number generation process, and the hash value calculation process of the data, and the hardware. A hardware security function unit that performs the encryption process, the random number generation process, and the hash value calculation process, respectively, and a function unit that performs the encryption process, the random number generation process, and the hash value calculation process. Is provided with a process switching unit for switching between the software security function unit and the hardware security function unit.

According to one aspect of the present invention, the transfer performance of encrypted communication can be improved.

It is a block diagram which shows schematic structure of the communication system which concerns on Embodiments 1 to 3. It is a block diagram which shows schematic structure of the gateway apparatus in Embodiment 1. FIG. It is a schematic diagram for demonstrating the data structure of the mapping table in Embodiment 1. FIG. It is a schematic diagram which shows an example of the mapping table in Embodiment 1. FIG. (A) and (B) are schematic views showing a hardware configuration example. It is a flowchart which shows the selection operation of S / W processing and H / W processing in Embodiment 1. It is a flowchart which shows the modification of the selection operation of S / W processing and H / W processing in Embodiment 1. FIG. FIG. 3 is a block diagram schematically showing a configuration of a gateway device according to a second embodiment. It is a schematic diagram for demonstrating the data structure of the compression table in Embodiment 2. It is a schematic diagram which shows an example of the compression table in Embodiment 2. It is a flowchart which shows the selection operation of presence / absence of data compression, and the selection operation of S / W processing and H / W processing in Embodiment 2. FIG. 3 is a block diagram schematically showing a configuration of a gateway device according to a third embodiment. It is a schematic diagram for demonstrating the data structure of the mapping table in Embodiment 3. FIG. It is a schematic diagram which shows an example of the mapping table in Embodiment 3. FIG. It is a flowchart which shows the selection operation of S / W processing and H / W processing in Embodiment 3. It is a block diagram which shows the 1st modification of the communication system which concerns on Embodiments 1 to 3. It is a block diagram which shows the 2nd modification of the communication system which concerns on Embodiments 1 to 3.

Embodiment 1.
FIG. 1 is a block diagram schematically showing the configuration of the communication system 100 according to the first embodiment.
The communication system 100 includes gateway devices 110A and 110B.
The first embodiment is an example in which the encrypted communication function is mounted on the gateway devices 110A and 110B corresponding to the edge of the network.

The gateway devices 110A and 110B are connected to the Internet 101 as a network, and form an encrypted communication tunnel 102 between the gateway devices 110A and 110B.
Here, since the gateway devices 110A and 110B are configured in the same manner, hereinafter, when it is not necessary to distinguish each of the gateway devices 110A and 110B, it is referred to as a gateway device 110.

In the communication system 100, the data transmitted from the subordinate terminal 103A is encrypted by the gateway device 110A, and the encrypted data is sent to the gateway device 110B. The gateway device 110B decodes the encrypted data, and the decoded data is sent to the subordinate terminal 103B.
Further, the data transmitted from the subordinate terminal 103B is encrypted by the gateway device 110B, and the encrypted data is sent to the gateway device 110A. The gateway device 110A decodes the encrypted data, and the decoded data is sent to the subordinate terminal 103A.
When it is not necessary to distinguish each of the subordinate terminals 103A and 103B, it is referred to as a subordinate terminal 103.

Cryptographic communication includes HTTPS communication or FTPS communication using SSL, SFTP communication or SCP communication using SSH, VPN communication, and the like. In addition, there are various VPNs according to the OSI layer model, L2TP or PPTP that performs encrypted communication processing in the second layer, IPsec that performs encrypted communication processing in the third layer, or encryption in the fourth layer or higher. There is an SSL VPN or the like that performs communication processing.

FIG. 2 is a block diagram schematically showing the configuration of the gateway device 110.
The gateway device 110 includes a network processing unit 111, a cryptographic communication processing unit 120, a security function unit 130, and a storage unit 140.
The network processing unit 111 functions as an interface with the Internet 101. For example, the network processing unit 111 receives an Ethernet frame or an IP packet. Here, Ethernet is a registered trademark.

The encrypted communication processing unit 120 performs encrypted communication of data. For example, the encrypted communication processing unit 120 performs an encrypted communication tunnel construction process and an encrypted communication process in order to perform encrypted communication on the Internet 101.
The cryptographic communication processing unit 120 includes a cryptographic communication tunnel construction processing unit 121, a cryptographic communication parameter storage unit 122, and a cryptographic communication processing unit 123.

The encrypted communication tunnel construction processing unit 121 performs an encrypted communication tunnel construction process for constructing an encrypted communication tunnel 102 with the encrypted communication processing unit 120 of the opposite gateway device 110 in order to perform encrypted communication. In the construction process of the encrypted communication tunnel 102, the encrypted communication tunnel construction processing unit 121 passes through the network processing unit 111 to the encrypted communication processing unit 120 of the opposite gateway device 110, and the encryption key and encryption used for the encrypted communication processing. Negotiation of parameters such as an encryption algorithm, a hash value calculation algorithm, an IP address of the gateway device 110, and a network address of a subordinate terminal 103 under the gateway device 110.
The cryptographic communication parameter storage unit 122 stores the parameters determined by negotiation by the cryptographic communication tunnel construction processing unit 121.

The encryption processing unit 123 performs encryption communication processing of the data to be transmitted by using the parameters determined by the negotiation by the encryption communication tunnel construction processing unit 121.
For example, the transmission target data including the data transmitted by another process unit (not shown) of the gateway device 110 and the received data received from the subordinate terminal 103 is subjected to encrypted communication processing from the network processing unit 111 to the encrypted communication processing unit 120. Passed. The other process unit is a Web server process unit that executes a Web server process, an FTP process unit that executes an FTP (File Transfer Protocol) process, and the like. After receiving the transmission target data, the encrypted communication processing unit 120 passes the transmission target data to the security function unit 130 together with the parameters stored in the encrypted communication parameter storage unit 122 in order to perform the encryption processing.

Then, the encryption processing unit 123 receives the encrypted transmission target data, which is the transmission target data encrypted by the security function unit 130, and encapsulates the data based on the parameters stored in the encrypted communication parameter storage unit 122. After adding the IP address information of the opposite gateway device 110, the processed data is passed to the network processing unit 111. The data passed to the network processing unit 111 is transmitted to the gateway device 110 at the opposite destination as transmission data.

The security function unit 130 performs encryption processing of the data to be transmitted.
The security function unit 130 includes a processing switching unit 131, an S / W security function unit 132, and an H / W security function unit 136.

The processing switching unit 131 switches the functional unit for performing data encryption processing between the S / W security function unit 132 and the H / W security function unit 136. For example, the processing switching unit 131 refers to the mapping table stored in the storage unit 140, and either the S / W security function unit 132 performs the encryption processing of the transmission target data passed from the encrypted communication processing unit 120. Alternatively, it is switched whether to be performed by the H / W security function unit 136.

The S / W security function unit 132 uses software to perform encryption processing of data to be transmitted, for example, random number generation processing, encryption processing, and hash value calculation processing.
For example, the S / W security function unit 132 includes an S / W random number generation unit 133, an S / W encryption processing unit 134, and an S / W hash value calculation unit 135.
The S / W random number generation unit 133 uses software to generate a random number used for encrypting the data to be transmitted.
The S / W encryption processing unit 134 uses software to encrypt the data to be transmitted. Here, the S / W encryption processing unit 134 corresponds to a plurality of encryption algorithms (a plurality of processing contents of the encryption processing).
The S / W hash value calculation unit 135 uses software to calculate a hash value for detecting falsification of encrypted data. Here, the S / W hash value calculation unit 135 corresponds to a plurality of hash value calculation algorithms (a plurality of processing contents of the hash value calculation process).

The H / W security function unit 136 uses hardware to perform encryption processing of data to be transmitted, for example, random number generation processing, encryption processing, and hash value calculation processing.
For example, the H / W security function unit 136 includes an H / W random number generation unit 137, an H / W encryption processing unit 138, and an H / W hash value calculation unit 139.
The H / W random number generation unit 137 uses hardware to generate a random number used for encrypting the data to be transmitted.
The H / W encryption processing unit 138 encrypts the data to be transmitted by using the hardware. Here, the H / W encryption processing unit 138 corresponds to a plurality of encryption algorithms.
The H / W hash value calculation unit 139 uses hardware to calculate a hash value for detecting falsification of encrypted data. Here, the H / W hash value calculation unit 139 corresponds to a plurality of hash value calculation algorithms.

The storage unit 140 stores a mapping table as switching information.
The mapping table is switching information indicating whether to select software or hardware for each combination of the processing content of the encryption process and the data size.

FIG. 3 is a schematic diagram for explaining the data structure of the mapping table.
As shown in FIG. 3, the mapping table 141 includes a plurality of algorithms (encryption processing) for performing encryption processing for each combination of random number generation processing, which is the processing content of encryption processing, and each of a plurality of data sizes. Each combination of each of the multiple processing contents) and each of the multiple data sizes, and each of the multiple algorithms for calculating the hash value (multiple processing secrets for calculating the hash value) and each of the multiple data sizes. Indicates whether to select software or hardware for each combination with.

Software based on the algorithm used for data size, random number generation processing, encryption processing, and hash value calculation in advance on the device that performs encrypted communication in order to switch between software and hardware. And by performing the processing using the hardware, the one having the shorter processing completion time is selected, and the selected one is stored in the mapping table 141 as shown in FIG.
For example, in the example shown in FIG. 3, the data size of the data to be transmitted is changed to 64 bytes, 128 bytes, 256 bytes, 512 bytes, 1024 bytes, ..., And the random number generation process for each data size. The S / W security function unit 132 was used in the encryption process using an encryption algorithm such as DES, 3DES, AES128, AES192 or AES256, and the hash calculation process using a hash value calculation algorithm such as MD5, SHA1 or SHA2. The throughput at the time of processing and at the time of processing using the H / W security function unit 136 are measured. Based on the measurement results, a mapping table is constructed by comparing which of the S / W security function unit 132 and the H / W security function unit 136 has the higher throughput performance and selecting the one with the higher throughput performance. ..

In addition, "S" in "S or H" in FIG. 3 indicates software (S / W security function unit 132), "H" indicates hardware (H / W security function unit 136), and "S". "or H" indicates that either software (S / W security function unit 132) or hardware (H / W security function unit 136) is selected.

FIG. 4 is a schematic diagram showing an example of a mapping table.
The mapping table 142 shown in FIG. 4 requires an overhead when passing the data to be transmitted to the H / W security function unit 136, and when the data size is small, the overhead occupies most of the processing time. An example is shown in which the processing performance of the W security function unit 132 is improved.

For example, in IPsec, which performs VPN communication and processes in the third layer of the OSI layer model, the IP packet received from the subordinate terminal 103 is encrypted and transferred. When AES256 is used as the encryption algorithm and SHA2 is used as the hash value calculation algorithm, if the data size of the first transfer data is 512 bytes, the S / W security function unit 132 is used in the random number generation process and encryption is performed. In the processing, the S / W security function unit 132 is used, and in the hash value calculation processing, the H / W security function unit 136 is used. When the data size of the second transfer data is 1024 bytes, the H / W security function unit 136 is used in all of the random number generation processing, the encryption processing, and the hash value calculation processing.

As described above, according to the mapping table, in the random number generation processing, which is the processing content of the encryption processing, switching is performed according to the data size of the transmission target data, and in the encryption processing, the data size and encryption of the transmission target data. Switching is performed according to the combination of the processing contents (algorithm) of the encryption process, and in the hash value calculation process, the switching is performed according to the combination of the data size of the data to be transmitted and the processing content (algorithm) of the hash value calculation process. ..

A part or all of the network processing unit 111, the encrypted communication tunnel construction processing unit 121, the encryption processing unit 123, the processing switching unit 131, and the H / W security function unit 136 described above may be, for example, FIG. 5A. As shown in, a processing circuit 10 such as a single circuit, a composite circuit, a programmed processor, a parallel programmed processor, an ASIC (Application Specific Integrated Circuits) or an FPGA (Field Programmable Gate Array) is used. Can be done.

Further, the S / W security function unit 132 is composed of, for example, as shown in FIG. 5B, a memory 11 and a processor 12 such as a CPU that executes a program stored in the memory 11. be able to. Such a program may be provided through a network, or may be recorded and provided on a recording medium. That is, such a program may be provided, for example, as a program product.

As shown in FIG. 5B, a part or all of the encrypted communication tunnel construction processing unit 121, the encryption processing unit 123, and the processing switching unit 131 shall be configured by the memory 11 and the processor 12. You can also.
Further, the encrypted communication parameter storage unit 122 can be configured by a volatile or non-volatile memory, and the storage unit 140 can be configured by a non-volatile memory.

Next, the operation will be described.
FIG. 6 is a flowchart showing a selection operation of S / W processing and H / W processing in the security function unit 130 of the first embodiment.

When the processing switching unit 131 of the security function unit 130 receives the transmission target data from the encrypted communication processing unit 120, the processing switching unit 131 refers to the mapping table stored in the storage unit 140 and performs random number generation processing from the data size of the transmission target data. Select whether to perform S / W processing or H / W processing (S10).
The data size of the transmission target data can be confirmed by referring to the header portion of the transmission target data. If the S / W process is selected, the process proceeds to step S11, and if the H / W process is selected, the process proceeds to step S12.
In step S11, the S / W random number generation unit 133 performs random number generation processing. In other words, random number generation processing using software is performed. Then, the process proceeds to step S13.
On the other hand, in step S12, the H / W random number generation unit 137 performs random number generation processing. In other words, random number generation processing using hardware is performed. Then, the process proceeds to step S13.

In step S13, the process switching unit 131 refers to the mapping table and performs S / W processing or H / W processing for the encryption processing based on the data size of the data to be transmitted and the encryption algorithm to be used. Choose whether to do it. The encryption algorithm to be used can be confirmed by referring to the parameters sent from the encrypted communication processing unit 120. If the S / W process is selected, the process proceeds to step S14, and if the H / W process is selected, the process proceeds to step S15.
In step S14, the S / W encryption processing unit 134 performs encryption processing. In other words, the encryption process using software is performed. Then, the process proceeds to step S16.
On the other hand, in step S15, the H / W encryption processing unit 138 performs encryption processing. In other words, the encryption process using hardware is performed. Then, the process proceeds to step S16.

In step S16, the processing switching unit 131 refers to the mapping table and performs S / W processing or H / W for the calculation of the hash value from the data size of the data to be transmitted and the hash value calculation algorithm to be used. Select whether to perform processing. The hash value calculation algorithm to be used can be confirmed by referring to the parameters sent from the cryptographic communication processing unit 120. If the S / W process is selected, the process proceeds to step S17, and if the H / W process is selected, the process proceeds to step S18.
In step S17, the S / W hash value calculation unit 135 performs the hash value calculation process. In other words, the hash value calculation process using software is performed.
On the other hand, in step S18, the H / W hash value calculation unit 139 performs the hash value calculation process. In other words, the hash value calculation process using hardware is performed.

The encrypted transmission target data that has been encrypted by the security function unit 130 is returned to the encrypted communication processing unit 120.

The encrypted transmission target data returned to the encrypted communication processing unit 120 is encapsulated in data and given IP address information of the opposite gateway device 110 based on the parameters stored in the encrypted communication parameter storage unit 122. After that, it is passed to the network processing unit 111 and transmitted as transmission data to the gateway device 110 at the opposite destination.

The gateway device 110 at the opposite destination, which has received the transmission data processed by encrypted communication, performs decryption processing and transfers the data to the subordinate terminal 103 or the gateway device 110 at the opposite destination.

As described above, according to the first embodiment, in the random number generation processing, the encryption processing, and the hash value calculation processing included in the encryption processing performed by the security function unit 130, according to each condition such as the algorithm and the data size, Since H / W processing and S / W processing can be switched, the processing method having the highest performance can be selected under each condition. Therefore, the performance of the device can be maximized when performing the encryption process.

As described above, the first embodiment is not limited to the gateway device 110 that supports both S / W processing and H / W processing for cryptographic processing. For example, due to the restrictions of the gateway device that performs processing, the gateway device that does not have the H / W security function unit 136 and can only perform S / W processing, or the gateway device that is fixed to H / W processing and cannot be switched. Also, the first embodiment can be applied. Such a case can be dealt with by setting all the mapping tables to S / W or H / W.

Alternatively, as shown in FIG. 7, by providing steps S20 and S24 in front of step S10 in FIG. 6, the entire mapping table can be confirmed and only H / W processing or S / W processing only. If is selected, the process can be simplified.
For example, when the entire mapping table selects only H / W processing in step S20, the processing switching unit 131 uses hardware for the H / W security function unit 136 in steps S21 to S23. Have the encryption process performed.
If only S / W processing is selected for the entire mapping table in step S24, the processing switching unit 131 uses software for the S / W security function unit 132 in steps S25 to S27. Let the process be performed.

Regarding the processing in steps S20 and S24, a flag indicating correspondence between S / W processing only, H / W processing only, or both is provided in the mapping table so that the processing switching unit 131 confirms the flag. You may do it.

In the first embodiment, the encrypted communication performed by the gateway device 110 is defined as VPN communication, and IPsec performed in the third layer of the OSI layer is described as an example, but other VPN encrypted communication may be similarly configured. can. For example, in L2TP or PPTP where VPN communication is performed and encrypted communication processing is performed in the second layer, Ethernet frames are targeted, and in SSL VPN or the like where encrypted communication processing is performed in the fourth layer or higher, data in the fourth layer or higher is targeted. The operation is the same except that.

Further, not only VPN communication but also HTTPS communication using SSL or encrypted communication of other protocols such as SFTP or SSH will operate in the same manner. In this case, the data to be transmitted is the data transmitted by another application. Become.

Embodiment 2.
In the first embodiment, the encryption process is branched into the H / W process and the S / W process, but in the second embodiment, the use and non-use of the data compression in the stage before the encryption process are also branched.

Generally, if the data to be transmitted is compressed and then encrypted, the amount of data is smaller and the throughput performance is improved. However, if the data to be transmitted is already compressed, the data to be transmitted is again compressed. Even with compression, the amount of data is often not so small. Therefore, in the second embodiment, the compression processing time is reduced by not performing the compression processing again for the transmission target data that has already been compressed.

As shown in FIG. 1, the communication system 200 according to the second embodiment includes gateway devices 210A and 210B.
The second embodiment is also an example in which the encrypted communication function is mounted on the gateway devices 210A and 210B, which are at the edge of the network.

The gateway devices 210A and 210B are connected to the Internet 101 as a network, and form an encrypted communication tunnel 102 between the gateway devices 210A and 210B.
Here, since the gateway devices 210A and 210B are configured in the same manner, hereinafter, when it is not necessary to distinguish each of the gateway devices 210A and 210B, it is referred to as a gateway device 210.

FIG. 8 is a block diagram schematically showing the configuration of the gateway device 210 according to the second embodiment.
The gateway device 210 includes a network processing unit 111, a cryptographic communication processing unit 120, a security function unit 230, and a storage unit 240.
The network processing unit 111 and the encrypted communication processing unit 120 of the gateway device 210 in the second embodiment are the same as those in the first embodiment.

The security function unit 230 performs compression processing and encryption processing of the data to be transmitted.
The security function unit 230 includes a processing switching unit 231, an S / W security function unit 132, an H / W security function unit 136, and a compression unit 250.
The S / W security function unit 132 and the H / W security function unit 136 of the security function unit 230 in the second embodiment are the same as those in the first embodiment.

The processing switching unit 231 performs the same processing as in the first embodiment, and also refers to the compression table stored in the storage unit 240 before selecting the encryption processing, and is passed from the encryption communication processing unit 120. Switch whether to perform compression processing of the data to be transmitted.
The compression unit 250 compresses the data to be transmitted according to the judgment of the processing switching unit 231.

The storage unit 240 stores a mapping table as switching information and a compression table as compression information.
The mapping table is the same as that of the first embodiment.

FIG. 9 is a schematic diagram for explaining the data structure of the compressed table.
As shown in FIG. 9, the compression table 243 is information indicating whether or not to compress the data for each type of data to be transmitted.
Here, "○" in "○ or ×" in FIG. 9 indicates that compression processing is performed, "×" indicates that compression processing is not performed, and "○ or ×" indicates that compression processing is performed. It indicates that either that or not performing the compression process is selected.

In creating a compressed table, for example, the data type is changed to text data, compressed image data, uncompressed image data, compressed video data, uncompressed video data, and so on. , For each data type, measure the throughput until the completion of encryption processing when data compression is used and when data compression is not used. Based on the measurement results, a compression table is constructed by comparing whether the throughput performance is higher when data compression is used or when data compression is not used, and by selecting a method with higher throughput performance.
For the encryption process here, a typical data size and algorithm may be used.

FIG. 10 is a schematic diagram showing an example of a compression table.
For example, in IPsec in which VPN communication is performed and processing is performed in the third layer of the OSI layer model, the IP packet received from the subordinate terminal 103 is encrypted and transferred. As shown in the compression table 244 of FIG. 10, when the first type of transfer data is text data, various encryption processes are performed after the data compression process. When the second type of transfer data is compressed video data, various encryption processes are performed without performing the data compression process.

Next, the operation will be described.
FIG. 11 is a flowchart showing a selection operation of presence / absence of data compression and a selection operation of S / W processing and H / W processing in the security function unit 230 of the second embodiment.

First, when the processing switching unit 231 of the security function unit 230 receives the transmission target data from the encrypted communication processing unit 120, the processing switching unit 231 refers to the compression table stored in the storage unit 240, and responds to the data content of the transmission target data. Then, whether or not to use data compression is selected (S30). If data compression is used, the process proceeds to step S31, and if data compression is not used, the process proceeds to step S10.

To determine whether or not to use data compression, the header portion in the data to be transmitted or the port number used for communication is confirmed.
Identification information of the data type is described in the header part in the transmission target data. For example, when the identification information of the JPEG image data is described in the header portion, the processing switching unit 231 determines that the image data is compressed. When the identification information of the MP4 video data is described in the header portion, the processing switching unit 231 determines that the video data has been compressed.
It should be noted that uncompressed data also exists in the video data, the image data, and the like. For example, a part of a BMP file or a TIFF file is uncompressed image data. Since it is possible to determine whether these are compressed or uncompressed based on the identification information of the header portion, the process switching unit 231 determines whether or not to perform the compression process based on these.

Further, since the port number used for communication is determined for each protocol, the processing switching unit 231 can determine the data type by checking the port number. For example, when the port number indicates a video streaming protocol such as Microsoft Media Server (MMS) or Real Time Streaming Protocol (RTSP), it corresponds to compressed video data. Specifically, since default port numbers are assigned such as 1755 for MMS and 554 for RSTP, the processing switching unit 231 determines whether or not to perform compression processing based on these.

Since the processes of steps S10 to S18 of FIG. 11 are the same as the processes of steps S10 to S18 of FIG. 6 in the first embodiment, detailed description thereof will be omitted.

As described above, according to the second embodiment, it is possible to switch whether or not to perform the compression process for each data type, so that it is possible to reduce the processing time loss due to the recompression of the already compressed data. Therefore, the transfer throughput can be improved.

The second embodiment is applicable not only to the gateway device 210 that supports compression processing as described above, but also to a gateway device that always performs compression processing or a gateway device that does not support compression processing. .. For example, in a gateway device that always performs data compression, all compression tables can be set to ○, and in a gateway device that does not support data compression, all compression tables can be set to ×.

Embodiment 3.
In the first and second embodiments, the processing on the transmitting side of the encrypted communication has been described, but in the third embodiment, the processing on the receiving side of the encrypted communication will be described.
As shown in FIG. 1, the communication system 300 according to the third embodiment includes gateway devices 310A and 310B.
The third embodiment is also an example in which the encrypted communication function is mounted on the gateway devices 310A and 310B corresponding to the edge of the network.

The gateway devices 310A and 310B are connected to the Internet 101 as a network, and form an encrypted communication tunnel 102 between the gateway devices 310A and 310B.
Here, since the gateway devices 310A and 310B are configured in the same manner, hereinafter, when it is not necessary to distinguish each of the gateway devices 310A and 310B, it is referred to as a gateway device 310.

FIG. 12 is a block diagram schematically showing the configuration of the gateway device 310.
The gateway device 310 includes a network processing unit 311, a cryptographic communication processing unit 320, a security function unit 330, and a storage unit 340.
The network processing unit 311 functions as an interface with the Internet 101. For example, the network processing unit 311 receives an Ethernet frame or an IP packet.

The encrypted communication processing unit 320 performs an encrypted communication tunnel construction process and an encrypted communication process in order to perform encrypted communication on the Internet 101.
The cryptographic communication processing unit 320 includes a cryptographic communication tunnel construction processing unit 121, a cryptographic communication parameter storage unit 122, and a decryption processing unit 324.
The cryptographic communication tunnel construction processing unit 121 and the cryptographic communication parameter storage unit 122 of the cryptographic communication processing unit 320 in the third embodiment are the same as those in the first embodiment.

The decryption processing unit 324 performs the encryption communication processing of the data to be decrypted by using the parameters determined by the negotiation by the encrypted communication tunnel construction processing unit 121.
For example, the decryption target data including the received data received from the Internet 101 is passed from the network processing unit 311 to the encrypted communication processing unit 320 in order to perform the encrypted communication processing. After receiving the data to be decrypted, the encryption communication processing unit 320 passes the data to be decrypted to the security function unit 330 together with the parameters stored in the encryption communication parameter storage unit 122 in order to perform the encryption processing.

Then, the decoding processing unit 324 receives the decrypted data decoded by the security function unit 330, performs processing according to the destination, and then sends the processed data to the destination as transmission data. For example, when the destination is the gateway device 310, the decoding processing unit 324 sends the decoded data from the network processing unit 311 to another process unit (not shown) of the gateway device 310. When the destination of the decrypted data is the subordinate terminal 103, the data is encapsulated, the IP address information of the subordinate terminal 103 to be the destination is added, and then the data is passed to the network processing unit 111 and the subordinate terminal. It is transmitted to 103 as transmission data.

The security function unit 330 performs encryption processing of the data to be transmitted.
The security function unit 330 includes a processing switching unit 331, an S / W security function unit 332, and an H / W security function unit 336.

The processing switching unit 331 refers to the mapping table stored in the storage unit 340, and the S / W security function unit 332 performs the encryption processing of the decryption target data passed from the encrypted communication processing unit 320, or the processing switching unit 331 performs the encryption processing. The H / W security function unit 336 switches whether to perform the operation.

The S / W security function unit 332 uses software to perform encryption processing of the data to be decrypted, for example, decryption processing and hash value calculation processing.
For example, the S / W security function unit 332 includes an S / W decoding processing unit 351 and an S / W hash value calculation unit 335.
The S / W decoding processing unit 351 decodes the data to be decoded by using software. Here, the S / W decoding processing unit 351 corresponds to a plurality of decoding algorithms (processing contents of the decoding process).
The S / W hash value calculation unit 335 uses software to calculate a hash value for detecting falsification of the data to be decoded. Here, the S / W hash value calculation unit 335 corresponds to a plurality of hash value calculation algorithms (process contents of the hash value calculation process).

The H / W security function unit 336 performs encryption processing of the data to be decrypted, for example, decryption processing and hash value calculation processing using hardware.
For example, the H / W security function unit 336 includes an H / W decoding processing unit 352 and an H / W hash value calculation unit 339.
The H / W decoding processing unit 352 decodes the data to be decoded by using the hardware. Here, the H / W decoding processing unit 352 corresponds to a plurality of decoding algorithms.
The H / W hash value calculation unit 339 uses hardware to calculate a hash value for detecting falsification of the data to be decoded. Here, the H / W hash value calculation unit 339 corresponds to a plurality of hash value calculation algorithms.

The storage unit 340 stores a mapping table as switching information.
The mapping table is information indicating whether to select software or hardware for each combination of the processing content of the encryption process and the data size.

FIG. 13 is a schematic diagram for explaining the data structure of the mapping table.
As shown in FIG. 13, the mapping table 345 is a combination of each of the plurality of algorithms for calculating the hash value (multiple processing contents for calculating the hash value) and each of the plurality of data sizes, and. It indicates whether to select software or hardware for each combination of each of the plurality of algorithms (multiple processing contents of the decoding process) for performing the decoding process and each of the plurality of data sizes.

In order to switch between software and hardware, software and hardware are based on the data size, the algorithm used for hash value calculation, and the algorithm used for encryption processing in advance on the device that performs encrypted communication. By performing the processing in each of the above, the one having the shorter processing completion time is selected, and the selected one is stored in the mapping table 345 as shown in FIG.
For example, in the example shown in FIG. 13, the data size of the data to be decoded is changed to 64 byte, 128 byte, 256 byte, 512 byte, 1024 byte, ..., And MD5, SHA1 or During processing using the S / W security function unit 332 in hash calculation processing using a hash value calculation algorithm such as SHA2 and decoding processing using a decoding algorithm such as DES, 3DES, AES128, AES192 or AES256. And, each throughput at the time of processing using the H / W security function unit 336 is measured. Based on the measurement results, a mapping table is constructed by comparing which of the S / W security function unit 332 and the H / W security function unit 336 has the higher throughput performance and selecting the one with the higher throughput performance. ..

In addition, "S" in "S or H" in FIG. 13 indicates software (S / W security function unit 332), "H" indicates hardware (H / W security function unit 336), and "S". "or H" indicates that either software (S / W security function unit 332) or hardware (H / W security function unit 336) is selected.

FIG. 14 is a schematic diagram showing an example of a mapping table.
The mapping table 346 shown in FIG. 14 requires an overhead when passing the data to be decoded to the H / W security function unit 336, and when the data size is small, the overhead occupies most of the processing time. An example is shown in which the processing performance of the W security function unit 332 is improved.

As described above, according to the mapping table, in the decoding process, switching is performed according to the combination of the data size of the data to be decoded and the processing content (algorithm) of the decoding process, and in the hash value calculation process, the decoding target is performed. Switching is performed according to the combination of the data size of the data and the processing content (algorithm) of the hash value calculation processing.

A part or all of the network processing unit 311, the encrypted communication tunnel construction processing unit 121, the decryption processing unit 324, the processing switching unit 331, and the H / W security function unit 336 described above may be, for example, FIG. 5A. As shown in, it can be composed of a single circuit, a composite circuit, a programmed processor, a parallel programmed processor, and a processing circuit 10 such as an ASIC or FPGA.

Further, the S / W security function unit 332 is composed of, for example, a memory 11 and a processor 12 such as a CPU that executes a program stored in the memory 11, as shown in FIG. 5 (B). be able to. Such a program may be provided through a network, or may be recorded and provided on a recording medium. That is, such a program may be provided, for example, as a program product.

As shown in FIG. 5B, a part or all of the encrypted communication tunnel construction processing unit 121, the decryption processing unit 324, and the processing switching unit 331 shall be configured by the memory 11 and the processor 12. You can also.
Further, the encrypted communication parameter storage unit 122 can be configured by a volatile or non-volatile memory, and the storage unit 340 can be configured by a non-volatile memory.

Next, the operation will be described.
FIG. 15 is a flowchart showing a selection operation of S / W processing and H / W processing in the security function unit 330 of the third embodiment.

When the processing switching unit 331 of the security function unit 330 receives the data to be decrypted from the encrypted communication processing unit 320, the processing switching unit 331 refers to the mapping table stored in the storage unit 340, and refers to the data size of the data to be transmitted and the hash value to be used. From the calculation algorithm, it is selected whether to perform S / W processing or H / W processing for the hash value calculation (S40). The hash value calculation algorithm to be used can be confirmed by referring to the parameters sent from the cryptographic communication processing unit 320. If the S / W process is selected, the process proceeds to step S41, and if the H / W process is selected, the process proceeds to step S42.
In step S41, the S / W hash value calculation unit 335 performs the hash value calculation process. In other words, the hash value calculation process using software is performed. Then, the process proceeds to step S43.
On the other hand, in step S42, the H / W hash value calculation unit 339 performs the hash value calculation process. In other words, the hash value calculation process using hardware is performed. Then, the process proceeds to step S43.

In step S43, the process switching unit 331 refers to the mapping table and performs S / W processing or H / W processing for the decoding process based on the data size of the data to be decoded and the decoding algorithm to be used. Choose whether to do it. The decryption algorithm to be used can be confirmed by referring to the parameters sent from the encrypted communication processing unit 320. If the S / W process is selected, the process proceeds to step S44, and if the H / W process is selected, the process proceeds to step S45.
In step S44, the S / W decoding processing unit 351 performs the decoding process. In other words, the decryption process using software is performed.
On the other hand, in step S45, the H / W decoding processing unit 352 performs the decoding process. In other words, the decryption process using hardware is performed.

The decrypted data that has been encrypted by the security function unit 330 is returned to the encrypted communication processing unit 320.

As described above, in the third embodiment, it is possible to maximize the performance of the device when performing the decoding process.

Since the data output in both the S / W processing and the H / W processing are the same in the first and second embodiments, the gateway device to which the encrypted communication is opposed has the function described in the third embodiment. You don't have to.

Further, the function of the gateway device 310 according to the third embodiment may be mounted on the gateway devices 110 and 210 according to the first or second embodiment. In such a case, it is possible to improve the efficiency of communication in both the transmitting side and the receiving side encryption processing.

As shown in FIG. 16, the first to third embodiments can be applied even when the subordinate terminal 403A under the gateway device 410A and the subordinate terminal 403B under the gateway device 410B perform encrypted communication. Is.
In such a case, the subordinate terminals 403A and 403B may include network processing units 111 and 311, cryptographic communication processing units 120 and 320, and security function units 130, 230 and 330.
The gateway devices 410A and 410B may be ordinary devices, unlike the gateway devices 110, 210 and 310 described above.

Further, the first to third embodiments can be applied even when the gateway devices 110A, 210A, 310A and the subordinate terminal 403B under the gateway device 410B perform encrypted communication, as shown in FIG. Is.
In such a case, the subordinate terminal 403B may include network processing units 111, 311 and cryptographic communication processing units 120 and 320, and security function units 130, 230 and 330.
The gateway device 410B may be a normal device, unlike the gateway devices 110, 210, and 310 described above.

That is, the first to third embodiments are not limited to the gateway devices 110, 210, and 310, and can be applied to communication devices that perform encrypted communication.

100,200,300 Communication system, 101 Internet, 102 Cryptographic communication tunnel, 103 Subordinate terminal, 110,210,310 Gateway device, 111,311 Network processing unit, 120,320 Cryptographic communication processing unit, 121 Cryptographic communication tunnel construction processing unit , 122 Cryptographic communication parameter storage unit, 123 Cryptographic processing unit, 324 Decryption processing unit, 130, 230, 330 Security function unit, 131,231,331 Processing switching unit, 132,332 S / W security function unit, 133 S / W Random number generation unit, 134 S / W encryption processing unit, 135,335 S / W hash value calculation unit, 136,336 H / W security function unit, 137 H / W random number generation unit, 138 H / W encryption processing unit , 139, 339 H / W hash value calculation unit, 140, 240, 340 storage unit, 250 compression unit, 351 S / W decryption processing unit, 352 H / W decryption processing unit.

Claims (9)

Cryptographic communication processing unit that performs encrypted communication of data and
As the data encryption process, an encryption process for encrypting the data, a random number generation process for generating a random number used for encrypting the data, and a hash value for detecting falsification of the encrypted data. Equipped with a security function unit that performs hash value calculation processing to calculate
The security function unit
A software security function unit that performs the encryption processing, the random number generation processing, and the hash value calculation processing of the data using software.
A hardware security function unit that performs the encryption processing, the random number generation processing, and the hash value calculation processing of the data using hardware.
For each of the encryption process, the random number generation process, and the hash value calculation process, the software security function unit and the function unit that causes each of the encryption process, the random number generation process, and the hash value calculation process are performed. A communication device characterized by having a processing switching unit for switching between hardware security function units. The processing switching unit causes the encryption processing to be performed between the software security function unit and the hardware security function unit according to the combination of the encryption processing algorithm and the data size of the data. Switching
The communication device according to claim 1. The processing switching unit switches between the software security function unit and the hardware security function unit to perform the random number generation process according to the data size of the data.
The communication device according to claim 1 or 2. The processing switching unit is a software security function unit and a hardware security function unit that causes the hash value calculation processing to be performed according to a combination of the hash value calculation processing algorithm and the data size of the data. Switching between
The communication device according to any one of claims 1 to 3. The security function unit further includes a compression unit that compresses the data.
The processing switching unit determines whether or not to compress the data according to the type of the data.
When the software security function unit or the hardware security function unit determines that the processing switching unit compresses the data, the software security function unit or the hardware security function unit performs the encryption processing on the data compressed by the compression unit. The communication device according to any one of claims 1 to 4, which is characterized. Cryptographic communication processing unit that performs encrypted communication of data and
As the data encryption process, a security function unit that performs a decryption process for decrypting the data and a hash value calculation process for calculating a hash value for detecting falsification of the decrypted data is provided.
The security function unit
A software security function unit that performs the decryption processing and the hash value calculation processing of the data using software.
A hardware security function unit that performs the decryption process and the hash value calculation process of the data using hardware.
For each of the decryption process and the hash value calculation process, a process of switching between the software security function unit and the hardware security function unit for performing each of the decryption process and the hash value calculation process. To have a switching unit
A communication device characterized by. The processing switching unit moves the functional unit for performing the decoding process between the software security function unit and the hardware security function unit according to the combination of the decoding processing algorithm and the data size of the data. Switching
The communication device according to claim 6. The processing switching unit is a software security function unit and a hardware security function unit that causes the hash value calculation processing to be performed according to a combination of the hash value calculation processing algorithm and the data size of the data. Switching between
The communication device according to claim 6 or 7. Further, a network processing unit that receives an Ethernet frame or an IP packet as the data is provided.
The encrypted communication processing unit performs VPN communication as the encrypted communication, and performs VPN communication.
The communication device according to any one of claims 1 to 8 , wherein the security function unit performs the encryption processing on the Ethernet frame or the IP packet.

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