JP2005094089A - Authentication apparatus, authentication target apparatus, authentication system, authentication method, authentication target method, program, and computer-readable recording medium recording the program - Google Patents

Abstract

PROBLEM TO BE SOLVED: To maintain a secure authentication function even when the authenticating side cannot have a function for generating a random number.
An input unit 111 for inputting first information and second information from an external device, and calculating the input first information to generate third information different from the first information. An adder 140; an encoder 130 that encrypts the calculated and generated third information using predetermined encryption key information to generate fourth information; and the external device generates the second information. The output unit 112 outputs the third information calculated and generated by the adder 140 to the external device, the second information input by the input unit 111, and the result generated by the encoder 130 A comparator 150 that determines whether or not the fourth information matches, and an authentication unit 180 that authenticates the external device when the comparator 150 determines that the fourth information matches. To do.
[Selection] Figure 1

Description

  The present invention relates to an authentication device, a device to be authenticated, an authentication system, an authentication method, a method to be authenticated, a program, or a computer-readable recording medium on which a program is recorded. In particular, the present invention relates to an authentication device and a device to be authenticated, which are used for embedded devices, home appliances, portable devices, and the like that are low in resources.

  As an authentication method using a challenge & (and) response method, a technique has been introduced in which a random number is generated on the authenticating side (server) and used for a challenge to the authenticated side (client) (non-patent literature). 1).

  Non-patent document 2 is introduced as a technique for generating random numbers on the authenticating side (VENDING MACHINE) (see non-patent document 2).

  Further, as a general technique for generating random numbers, means for generating random numbers within the device itself and withstanding analysis from the outside is disclosed (see Patent Document 1).

  In addition, a method is disclosed in which the security of authentication is improved by remembering the most recent exchange of random numbers and not using the used random number values (see Patent Document 2).

Also, a means for generating random numbers with a small amount of resources has been disclosed, and means for generating random numbers within the device itself is disclosed (see Patent Document 3).
JP 2000-242470 A JP 2001-177519 A JP-A-10-247140 Takumi Ohashi “User Authentication”, Makinouchi Lab “Internet Training” Web page, http: // www. db. is. kyushu-u. ac. jp / linkou / internet / b-8. ppt (13th page) “Security of electronic transactions using SHA-1”, http: // pdfserv. maxim-ic. com / arpf / AppNotes / AD0115J. pdf (2nd page, Fig. 1)

  However, when an authentication function is given to an existing device or when the authentication function must be realized with limited resources, the authenticating side may necessarily have a function for generating a random number. There was a problem that it might not be possible. For example, taking a battery used for a digital camera as an example, a battery as a so-called off-brand product with poor quality is produced by an off-brand manufacturer and is on the market. In order to eliminate this off-brand product, it is effective that the digital camera authenticates the battery. If the digital camera uses only the authenticated battery as the power source, this off-brand product can be eliminated. Here, when an authentication function is installed in a digital camera, it is inconvenient for a digital camera with limited resources to generate a random number in the digital camera on the authentication side as in Non-Patent Documents 1 and 2 above. It is. However, in the challenge-and-response authentication method, if the authentication side that outputs the challenge cannot output irregular challenge information, there is a risk that the malicious attacker (for example, the above-mentioned off-brand manufacturer) may overlook the response information. There was a problem that there was. If the challenge information and the corresponding response information are overlooked, it becomes a target of a so-called repeat attack.

  An object of the present invention is to maintain a safe authentication function even when the authenticating side cannot have a function of generating a random number.

  Another object of the present invention is to maintain a secure authentication function even when a challenge and response authentication method is used based on information from an authenticated side that may be a fake.

An authentication apparatus according to the present invention includes an input unit that inputs first information and second information from an external device;
A computing unit that computes the first information input by the input unit to generate third information different from the first information;
An encryption unit that encrypts the third information calculated and generated by the calculation unit using predetermined encryption key information, and generates fourth information;
An output unit for outputting the third information calculated and generated by the calculation unit to generate the second information by the external device to the external device;
A determination unit that determines whether the second information input by the input unit matches the fourth information generated as a result of encryption by the encryption unit;
And an authentication unit that authenticates the external device when the determination unit determines that they match.

The device to be authenticated according to the present invention is a device to be authenticated that receives authentication from the authentication device using a challenge and response method,
A random number generator for generating random numbers;
An output unit that outputs the random number generated by the random number generation unit to the authentication device as random number information;
An input unit for inputting challenge information based on the random number information from the authentication device;
An encryption unit that encrypts the challenge information input by the input unit using predetermined encryption key information to generate response information;
And an output unit that outputs response information generated as a result of encryption by the encryption unit to the authentication device in order to receive authentication by the authentication device.

The authentication device according to the present invention is an authentication device that performs mutual authentication with an external device using a challenge and response method,
A random number generator for generating random numbers;
An output unit that outputs the random number generated by the random number generation unit to the external device as random number information;
An input unit for inputting challenge information based on the random number information from the external device;
An encryption unit that encrypts the challenge information input by the input unit using predetermined encryption key information to generate response information;
An output unit for outputting response information generated as a result of encryption by the encryption unit to be authenticated by the external device to the authentication device;
The encryption unit generates authentication confirmation information used for authentication confirmation for authenticating the external device by encrypting the random number generated by the random number generation unit using predetermined encryption key information,
The input unit further inputs response information based on the random number information for authenticating the external device from the external device,
The authentication target device further includes a determination unit that determines whether or not the response information input by the input unit matches the authentication confirmation information generated as a result of encryption by the encryption unit;
And an authentication unit that authenticates the external device when the determination unit determines that they match.

The authentication device according to the present invention is an authentication device that performs mutual authentication with an external device using a challenge and response method,
An input unit for inputting a random number generated by an external device as first challenge information;
An encryption unit that encrypts a random number as first challenge information input by the input unit using predetermined encryption key information and generates first response information for receiving authentication from the external device;
An output unit that outputs the first response information generated as a result of encryption by the encryption unit to the external device;
A calculation unit that calculates a random number as the first challenge information input by the input unit and generates second challenge information different from the first challenge information;
An encryption unit that encrypts the second challenge information calculated and generated by the calculation unit using predetermined encryption key information to generate authentication confirmation information used for authentication confirmation for authenticating the external device; With
The output unit outputs the second challenge information calculated and generated by the calculation unit to generate second response information for the external device to receive authentication from the authentication device, and outputs the second challenge information to the external device.
The input unit inputs the second response information from the external device,
The authentication device further includes:
A determination unit that determines whether or not the second response information input by the input unit matches the authentication confirmation information generated as a result of encryption by the encryption unit;
And an authentication unit that authenticates the external device when the determination unit determines that they match.

The mutual authentication system according to the present invention is a mutual authentication system that performs mutual authentication between a first and a second communication device using a challenge and response method,
A capability determination unit that determines whether at least one of the first and second communication devices has the capability of generating a random number;
In the mutual authentication system, a random number generated by one communication device is transmitted from one of the first and second communication devices determined to have a capability of generating a random number by the capability determination unit to the other communication device. It is output as random number information, and mutual authentication is performed between the first and second communication devices based on the output random number information.

  According to the present invention, a safe authentication function can be maintained even when the authenticating side cannot have a function of generating a random number.

  According to the present invention, a secure authentication function can be maintained even when a random number is obtained from the authenticated side.

  According to the present invention, a secure authentication function can be maintained even when a challenge-response authentication method is used based on information from an authenticated side that may be a fake.

  According to the present invention, there is provided an authentication device that does not have a random number generation device that burdens resources, and that authenticates a device to be authenticated while maintaining a secure authentication function even when a challenge and response method is used. Can be provided.

  ADVANTAGE OF THE INVENTION According to this invention, even when a challenge & response system is used, the to-be-authenticated apparatus which receives a certification | authentication with a secure authentication function from an authentication apparatus can be provided.

  According to the present invention, even when a challenge and response method is used between devices having a random number generation function on one side, mutual authentication can be performed while maintaining a secure authentication function.

Embodiment 1 FIG.
First, in the general authentication methods of Non-Patent Documents 1 and 2 above, a random number is generated on the authenticating side, and this is sent as a challenge to the authenticated side. Then, the challenge is encrypted and the authentication side compares the result of the encryption process returned as a response from the authenticated side to determine whether the authenticated side is the correct device. In this case, since the challenge value differs for each authentication process, it is not affected by a so-called repeat attack caused by intercepting communication between devices.

  FIG. 1 is a diagram showing a configuration in the first embodiment.

  In FIG. 1, an authentication device 100 is a communication unit 110, an encoder 130 (an example of an encryption unit), an adder 140 (an example of an arithmetic unit and an arithmetic unit), and a comparator 150 (an example of a determination unit). ) And an authentication unit 180. The communication unit 110 includes an input unit 111 and an output unit 112. Other configurations are omitted.

  The device to be authenticated 200 includes a communication unit 210, an encoder 230 (an example of an encryption unit), and a random number generator 260 (an example of a random number generation unit). The communication unit 210 has an input unit 211 and an output unit 212. Other configurations are omitted.

  FIG. 2 is a flowchart showing an authentication procedure of each device in the first embodiment.

  As the random number generation process, the random number generator 260 (RNG in FIG. 2) of the authenticated apparatus 200 that receives authentication from the authentication apparatus 100 using the challenge and response method generates a random number.

  As a first output process from the authenticated device 200 side, the random number generated by the random number generator 260 is output to the authentication device 100 as random number information.

  As a first input process on the authentication device 100 side, the input unit 111 inputs random number information as an example of first information from the authenticated device 200 that is an external device for the authentication device 100. In other words, the first information has random value information generated irregularly. The random value information is generated in the authenticated device 200 that is an external device for the authentication device 100.

  As a calculation process on the authentication device 100 side, the adder 140 (calculation X in FIG. 2) is different from the first information by calculating random number information as an example of the first information input by the input unit 111. Challenge information as an example of the third information is generated. (In other words, the adder 140 converts the random number information as an example of the first information input by the input unit 111 into challenge information as an example of third information different from the first information.) Here, as an example, the adder 140 generates challenge information by adding (calculating) a predetermined value to the random number information. Here, the input unit 111 receives a plurality of pieces of first information, and the adder 140 uses the input unit 111 to input the plurality of first pieces of information even if the plurality of pieces of first information are the same information. Each time the first information is input, the third information is generated by calculating the first information of the plurality of first information. That is, the predetermined value added by the adder 140 in order to eliminate the interception of the same challenge value and the paired response value due to the input of the same value, which may be performed by a malicious user, will be described below. Thus, a different value is used for each authentication process.

  As an encryption process on the authentication device 100 side, the encoder 130 (ENC in FIG. 2) is an example of predetermined encryption key information, which is challenge information, which is an example of third information calculated and generated by the adder 140. Authentication confirmation information, which is an example of fourth information used for authentication confirmation for authenticating the device 200 to be authenticated, is encrypted by using a common key.

  As an output process on the authentication device 100 side, the output unit 112 includes a first output calculated and generated by the adder 140 so that the authenticated device 200 serving as the external device generates response information as an example of the second information. The challenge information, which is an example of the information 3, is output to the authenticated device 200 serving as the external device.

  As an input process on the authenticated device 200 side, the input unit 211 inputs challenge information as an example of third information calculated and generated by the adder 140 based on the random number information from the authentication device 100.

  As an encryption step on the authenticated device 200 side, the encoder 230 encrypts the challenge information input by the input unit 211 using the same common key as the authentication device 100 side, which is an example of predetermined encryption key information, and responds. Generate information.

  As a second output step on the authenticated device 200 side, the output unit 212 outputs response information generated as a result of encryption by the encoder 230 to the authentication device 100 in order to receive authentication by the authentication device 100. .

  As a second input process on the authentication device 100 side, the input unit 111 inputs response information as an example of second information from the authenticated device 200 serving as an external device.

  As a determination step on the authentication apparatus 100 side, the comparator 150 includes response information as an example of second information input by the input unit 111 and fourth information generated as a result of encryption by the encoder 130. It is determined by comparing whether or not the authentication confirmation information as an example matches.

  As an authentication process on the authentication device 100 side, the authentication unit 180 authenticates the device 200 to be authenticated, which is the external device, when the comparator 150 determines that they match.

  Then, when the device to be authenticated 200 is authenticated by the authentication device 100, each necessary process is performed with another configuration not shown. For example, when taking a digital camera and a battery used for the digital camera as an example, when the digital camera serving as the authentication device 100 authenticates the battery serving as the device to be authenticated 200, the digital camera supplies power from the subsequent battery. Receive. Alternatively, the digital camera supplies power from another power supply device (for example, an AC adapter) to the battery and charges the battery. The authentication device 100 and the device to be authenticated 200 are not limited to a digital camera and a battery used for the digital camera. For example, it is effective for an authentication device and a device to be authenticated, which are used for a built-in device, a household appliance, a portable device, and the like, which have small resources.

  As described above, in the first embodiment, the authenticating side cannot generate a random number due to resource restrictions or the like, and the authenticated side can generate a random number. In this case, the random number sent from the authenticated side is processed (calculated or converted) by the adder 140 as an example of the calculation unit or the conversion unit, and a challenge is generated. I will send it back. At this time, if the adder 140 performs processing that makes it possible to associate a random number and a challenge on a one-to-one basis, a malicious attacker can perform a repeat attack by intercepting authentication communication between legitimate devices. turn into. In other words, the same challenge is always used when the counterfeit device to be authenticated always gives the same value as the random number to the authenticator, and the random number used for correct authentication between the authorized devices and the corresponding challenge The response pair is used for the attack.

  Therefore, in the first embodiment, in the processing of the adder 140 as an example of the calculation unit or the conversion unit, even if the random numbers that are input to the authentication device are the same, the challenge value that is output is different every time. Is one of the features. For example, if the authenticating device has a timekeeping function, if the adder 140 performs processing such as simply adding the current time to a random number, for example, in seconds, the challenge always has a different value for the random number. Can be sent to the authenticated side, and repeat attacks can be eliminated. In general, in the challenge and response authentication method, the quality of random numbers is important. However, as long as the quality of a random number generator 260 (random number generator: RNG) on the authenticated side is satisfied, as in Embodiment 1. Even if there is no random number generator on the authentication side, there is no problem as an authentication system. As for the quality of the random number, for example, in 64-bit information, it can be said that the quality is high if a random number can be generated in the entire 64 bits. In other words, those that can generate random numbers in only a part of 64 bits have low quality. In addition, the quality of random numbers is also high if random numbers are not generated from a fixed calculation formula.

  The predetermined value added by the adder 140 is not limited to the time value, and may be a value that changes every moment of the authentication side device. Further, the calculation unit or the conversion unit is not limited to the adder 140, and a simple random number generator (the quality may be worse than the original random number) may be used. Here, as an example of a simple random number generator, for example, in a 64-bit information, a random number generator that can generate a random number only in a part of 64 bits (for example, 2 bits, 8 bits, etc.) may be used. Absent. It is not necessary to add a twist to the value input as a random number from the device to be authenticated and cause the device to be authenticated to predict the challenge value.

  Further, a time is used as a method (variation of arithmetic processing or conversion processing) added by the adder 140, and a challenge to be sent to the authenticated side is generated by adding this time information to a random number received from the authenticated side. In cases where the time information is physically attacked and fixed time data may be forced, the value changes by reading the time information more than once. After confirming that the challenge information is generated, the challenge information may be generated. This is not limited to the case of using time information, and such a check mechanism may be provided in order to use a constantly changing value.

  As described above, by using an adder with less resources or a simple random number generator on the authentication side compared to a highly reliable random number generator, it is safer even if a highly reliable random number generator is not installed. Authentication can be performed.

Embodiment 2. FIG.
In the first embodiment, the one-way authentication method is used. In the second embodiment, a case where mutual authentication is performed between devices will be described.

  FIG. 3 is a diagram showing a configuration in the second embodiment.

  In FIG. 3, the authentication apparatus 300 includes a communication unit 210, an encoder 230 (an example of an encryption unit), a random number generator 260 (an example of a random number generation unit), and a comparator 250 (an example of a determination unit). , An authentication unit 280 is provided. The communication unit 210 has an input unit 211 and an output unit 212. The authentication device 100 is the same as that in FIG. The authentication apparatus 300 further includes a comparator 250 and an authentication unit 280 with respect to the apparatus 200 to be authenticated in FIG. Other configurations are omitted.

  In the second embodiment, means (mutual authentication system) for performing mutual authentication between the authentication device 100 and the authentication device 300 using a challenge and response method will be described.

  FIG. 4 is a flowchart showing an authentication procedure of each device in the second embodiment.

  As a random number generation process on the authentication device 300 side, the random number generator 260 generates a random number.

  As a first output process on the authentication device 300 side, the output unit 212 outputs the random number generated by the random number generator 260 to the authentication device 100 as an external device as the authentication device 300 as first challenge information.

  As a first encryption step on the authentication device 300 side, the encoder 230 encrypts the random number generated by the random number generator 260 using predetermined encryption key information to authenticate the authentication device 100. Authentication confirmation information used for the purpose is generated.

  As a first input process on the authentication device 100 side, the input unit 111 inputs, as first challenge information, a random number generated by the authentication device 300 serving as an external device for the authentication device 100.

  As a first encryption step on the authentication device 100 side, the encoder 130 encrypts a random number as first challenge information input by the input unit 111 using predetermined encryption key information, and takes the authentication device 100 as the first encryption step. First response information for receiving authentication from the authentication device 300 as an external device is generated.

  As a first output process on the authentication device 100 side, the output unit 112 authenticates the first response information generated as a result of encryption by the encoder 130 from the authentication device 300 serving as an external device using the authentication device 100. In order to receive, it outputs to the said authentication apparatus 300.

  As a first input process on the authentication device 300 side, the input unit 211 includes a first based on the first challenge information for authenticating the authentication device 100 from the authentication device 100 serving as an external device as the authentication device 300. Enter response information.

  As a determination step on the authentication device 300 side, the comparator 250 determines whether or not the first response information input by the input unit 211 matches the authentication confirmation information generated as a result of encryption by the encoder 230. Judging.

  As an authentication process on the authentication device 300 side, when it is determined by the comparator 250 that they match, the authentication device 100 authenticates the authentication device 100 serving as an external device.

  As a calculation process on the authentication device 100 side, the adder 140 calculates a random number as the first challenge information input by the input unit 111 and generates second challenge information different from the first challenge information. .

  As a second encryption step on the authentication device 100 side, the encoder 130 encrypts the second challenge information calculated and generated by the adder 140 using predetermined encryption key information, and the authentication device 100 externally The authentication confirmation information used for the authentication confirmation for authenticating the authentication apparatus 300 as the apparatus is generated.

  As a second output process on the authentication device 100 side, the output unit 112 uses the adder 140 to generate second response information for the authentication device 300 to be authenticated by the authentication device 300 serving as an external device. The calculated and generated second challenge information is output to the authentication device 300.

  As a second input step on the authentication device 300 side, the input unit 211 receives a second challenge based on the first challenge information output by the output unit 212 from the authentication device 100 serving as an external device for the authentication device 300. Enter information.

  As a second encryption step on the authentication apparatus 300 side, the encoder 230 generates second response information by encrypting the second challenge information input by the input unit 211 using predetermined encryption key information. .

  As a second output process on the authentication device 300 side, the output unit 212 generates a second response generated as a result of being encrypted by the encoder 230 in order to be authenticated by the authentication device 100 serving as an external device. The information is output to the authentication device 100.

  As a second input process on the authentication device 100 side, the input unit 111 inputs the second response information from the external device.

  As a determination step on the authentication device 100 side, the comparator 150 determines whether or not the second response information input by the input unit 111 matches the authentication confirmation information generated as a result of being encrypted by the encoder 130. Judging.

  As an authentication process on the authentication device 100 side, the authentication unit 180 authenticates the authentication device 300 serving as an external device for the authentication device 100 when the comparator 150 determines that the two match.

  Then, when mutual authentication is performed between the authentication device 100 and the authentication device 300, each necessary process is performed by another configuration not shown. For example, when taking a digital camera and a battery used for the digital camera as an example, when mutual authentication is performed between the digital camera serving as the authentication device 100 and the battery serving as the authentication device 300, the digital camera starts from the subsequent battery. Receive the power supply. Alternatively, the digital camera supplies power from another power supply device (for example, an AC adapter) to the battery and charges the battery. The authentication device 100 and the authentication device 300 are not limited to a digital camera and a battery used for the digital camera. For example, it is effective for an authentication device used for a built-in device, a home appliance, a portable device, and the like having a small resource.

  In the second embodiment, when the first embodiment is extended to mutual authentication, the authentication device 300 (authenticated side in the first embodiment) authenticates the authentication device 100 (authenticated side in the first embodiment). The first response only generates a fixed response even if cryptographic processing is applied to a fixed random number value. This is because the authentication device 300 (the authenticated side in the first embodiment) is a legitimate device. There is no problem without the random value being fixed. Further, the authentication device 100 (authentication side in the first embodiment) performs a second challenge (random number generation from the device side that does not have a random number generator) by performing an operation by an adder 140 as an example of a calculation unit or a conversion unit. Since the challenge to the device side having the device does not correspond to the first random number one-to-one, it becomes possible to eliminate the repeat attack. The second embodiment is characterized in that processing is started from the side having an RNG (random number generator) when performing mutual authentication. In other words, the challenge and response value is generated based on random random numbers that are irregular.

  In the processing of the adder 140 as an example of the calculation unit or the conversion unit, the challenge value that is an output is different every time even if the random numbers that are input to the authentication device 100 are the same. This is the same as the first embodiment. A specific example method is the same as that of the first embodiment. It is important for the side outputting the challenge to make a twist so that the opponent (especially a malicious attacker) does not see the challenge value. In the second embodiment, the authentication device 300 uses the random number generator 260, and the authentication device 100 uses the adder 140 to perform a twisting process so that the opponent (especially a malicious attacker) does not see the challenge value. doing. In particular, in Embodiment 2, mutual authentication with higher security can be performed by starting processing from the authentication device 300 side that can generate a random number with high accuracy in the random number generator 260.

Embodiment 3 FIG.
In the third embodiment, when the mutual authentication method in the second embodiment is further expanded to perform mutual authentication between the first and second communication apparatuses using the challenge and response method, the first and second A means (mutual authentication system) for performing mutual authentication with higher security by determining which of the authentication apparatuses 100 and 300 as the communication apparatus to start processing from will be described.

  FIG. 5 is a diagram showing a configuration in the third embodiment.

  In FIG. 5, the authentication device 100 further includes a capability determination unit 170 as compared to FIG. 3. The authentication device 300 is the same as that shown in FIG. In FIG. 5, the capability determination unit 170 is provided on the authentication device 100 side, but may be provided on the authentication device 300 side. Or both may be provided.

  The capability determination unit 170 determines whether at least one of the first and second communication devices (here, the authentication devices 100 and 300) has the capability of generating a random number.

  The mutual authentication system according to the third embodiment is configured such that one communication device is transferred from one of the first and second communication devices determined by the capability determination unit 170 to have a capability of generating a random number to the other communication device. Is output as random number information, and mutual authentication is performed between the first and second communication devices based on the output random number information. In other words, the capability determination unit 170 communicates between the authentication devices 100 and 300 using the communication units 110 and 210, determines a device including a random number generator, and determines the determined device (the authentication device in FIG. 5). 300), each process in the second embodiment is started.

  As described above, it is possible to perform mutual authentication with higher security by checking the capability as a mutual authentication function in advance and starting processing from the device side that can generate a high-quality random number.

  In the above description, what has been described as “˜device”, “encoder”, or “˜unit” in the description of each embodiment can be configured partially or entirely by a computer-operable program. These programs can be created in C language, for example. Alternatively, HTML, SGML, or XML may be used.

  Further, in the above description, in the case where what has been described as “˜device”, “encoder”, or “˜unit” in the description of each embodiment is configured by a program that can be partially or entirely operated by a computer, the authentication device Although not shown, the authentication target device 200 includes a CPU (Central Processing Unit) that executes a program. The CPU is connected to a built-in or RAM (Random Access Memory) (which is an example of a storage device or a storage unit) via a bus, and is connected to a communication board capable of communicating with the outside. Further, it may be connected to a ROM (Read Only Memory) (which is an example of a storage device).

  The program group is built in the CPU. The program group is executed by a CPU, OS, and the like. The storage device stores the result of each process.

  When configured by a program, the program group stores a program to be executed by what has been described as “˜device”, “encoder”, or “˜unit” in the description of each embodiment.

  In addition, what has been described as “˜device”, “encoder”, or “˜unit” in the description of each embodiment may be realized by firmware stored in a ROM. Alternatively, it may be implemented by software, hardware, or a combination of software, hardware, and firmware.

  The program for implementing each of the above embodiments is based on other recording media such as a magnetic disk device, FD (Flexible Disk), optical disk, CD (Compact Disk), MD (Mini Disk), DVD (Digital Versatile Disk), etc. You may memorize | store using a recording device.

  Since such an implementation is adopted, there is an effect that safe authentication or mutual authentication can be performed. And it is applicable to uses, such as authentication and a to-be-authenticated apparatus, which are few resources as mentioned above, and are used for an embedded device, a household appliance, and a portable device.

2 is a diagram showing a configuration in the first embodiment. FIG. FIG. 3 is a flowchart showing an authentication procedure of each device in the first embodiment. FIG. 10 is a diagram showing a configuration in a second embodiment. FIG. 10 is a flowchart showing an authentication procedure of each device in the second embodiment. 10 is a diagram showing a configuration in a third embodiment. FIG.

Explanation of symbols

  100 authentication device, 110 communication unit, 111 input unit, 112 output unit, 130 encoder, 140 adder, 150 comparator, 170 capability determination unit, 180 authentication unit, 200 device to be authenticated, 210 communication unit, 211 input unit, 212 Output unit, 230 encoder, 250 comparator, 260 random number generator, 280 authentication unit, 300 authentication device.

Claims (17)

An input unit for inputting the first information and the second information from an external device;
A computing unit that computes the first information input by the input unit to generate third information different from the first information;
An encryption unit that encrypts the third information calculated and generated by the calculation unit using predetermined encryption key information, and generates fourth information;
An output unit for outputting the third information calculated and generated by the calculation unit to generate the second information by the external device to the external device;
A determination unit that determines whether the second information input by the input unit matches the fourth information generated as a result of encryption by the encryption unit;
An authentication device, comprising: an authentication unit that authenticates the external device when the determination unit determines that they match.   The authentication apparatus according to claim 1, wherein the first information includes random value information generated irregularly.   The authentication apparatus according to claim 2, wherein the random value information is generated in the external device. The input unit inputs a plurality of pieces of first information,
The arithmetic unit is configured to output the plurality of first information each time the first information of the plurality of first information is input by the input unit, even if the plurality of first information is the same information. The authentication apparatus according to claim 1, wherein different third information is generated by calculating each first information. The authentication device authenticates the external device by a challenge and response method,
The output unit outputs third information as challenge information to the external device,
The external device encrypts the third information output by the output unit using the predetermined encryption key information to generate the second information,
The authentication apparatus according to claim 1, wherein the input unit inputs the second information generated as a result of encryption by the external device as response information. An authenticated device that receives authentication from an authentication device using a challenge and response method,
A random number generator for generating random numbers;
An output unit that outputs the random number generated by the random number generation unit to the authentication device as random number information;
An input unit for inputting challenge information based on the random number information from the authentication device;
An encryption unit that encrypts the challenge information input by the input unit using predetermined encryption key information to generate response information;
An authentication target device comprising: an output unit that outputs response information generated as a result of encryption by the encryption unit to the authentication device in order to receive authentication by the authentication device. An authentication device that performs mutual authentication with an external device using a challenge and response method,
A random number generator for generating random numbers;
An output unit that outputs the random number generated by the random number generation unit to the external device as random number information;
An input unit for inputting challenge information based on the random number information from the external device;
An encryption unit that encrypts the challenge information input by the input unit using predetermined encryption key information to generate response information;
An output unit for outputting response information generated as a result of encryption by the encryption unit to be authenticated by the external device to the authentication device;
The encryption unit generates authentication confirmation information used for authentication confirmation for authenticating the external device by encrypting the random number generated by the random number generation unit using predetermined encryption key information,
The input unit further inputs response information based on the random number information for authenticating the external device from the external device,
The authentication target device further includes a determination unit that determines whether or not the response information input by the input unit matches the authentication confirmation information generated as a result of encryption by the encryption unit;
An authentication device, comprising: an authentication unit that authenticates the external device when the determination unit determines that they match. An authentication device that performs mutual authentication with an external device using a challenge and response method,
An input unit for inputting a random number generated by an external device as first challenge information;
An encryption unit that encrypts a random number as first challenge information input by the input unit using predetermined encryption key information and generates first response information for receiving authentication from the external device;
An output unit that outputs the first response information generated as a result of encryption by the encryption unit to the external device;
A calculation unit that calculates a random number as the first challenge information input by the input unit and generates second challenge information different from the first challenge information;
An encryption unit that encrypts the second challenge information calculated and generated by the calculation unit using predetermined encryption key information to generate authentication confirmation information used for authentication confirmation for authenticating the external device; With
The output unit outputs the second challenge information calculated and generated by the calculation unit to generate second response information for the external device to receive authentication from the authentication device, and outputs the second challenge information to the external device.
The input unit inputs the second response information from the external device,
The authentication device further includes:
A determination unit that determines whether or not the second response information input by the input unit matches the authentication confirmation information generated as a result of encryption by the encryption unit;
An authentication device, comprising: an authentication unit that authenticates the external device when the determination unit determines that they match. A mutual authentication system that performs mutual authentication between a first and a second communication device using a challenge and response method,
A capability determination unit that determines whether at least one of the first and second communication devices has the capability of generating a random number;
In the mutual authentication system, a random number generated by one communication device is transmitted from one of the first and second communication devices determined to have a capability of generating a random number by the capability determination unit to the other communication device. A mutual authentication system that outputs as random number information and performs mutual authentication between the first and second communication devices based on the output random number information. An input step of inputting the first information and the second information from an external device;
A calculation step of calculating the first information input by the input step to generate third information different from the first information;
An encryption step of generating fourth information by encrypting the third information calculated and generated by the calculation step using predetermined encryption key information;
An output step of outputting the third information calculated and generated by the calculation step in order for the external device to generate the second information to the external device;
A determination step of determining whether or not the second information input by the input step matches the fourth information generated as a result of encryption by the encryption step;
An authentication method comprising: an authentication step of authenticating the external device when it is determined to match by the determination step. An authenticated method for receiving authentication from an authentication device using a challenge and response method,
A random number generation step for generating a random number;
An output step of outputting the random number generated by the random number generation step to the authentication device as random number information;
An input step of inputting challenge information based on the random number information from the authentication device;
An encryption step of encrypting the challenge information input in the input step using predetermined encryption key information to generate response information;
An authentication method comprising: an output step of outputting response information generated as a result of encryption by the encryption step to the authentication device in order to receive authentication by the authentication device. An authentication method for performing mutual authentication with an external device using a challenge and response method,
A random number generation step for generating a random number;
A first output step of outputting the random number generated by the random number generation step to the external device as first challenge information;
A first encryption step for encrypting the random number generated by the random number generation step using predetermined encryption key information to generate authentication confirmation information used for authentication confirmation for authenticating the authentication device;
A first input step of inputting first response information based on the first challenge information for authenticating the external device from the external device;
A determination step of determining whether or not the first response information input in the first input step matches the authentication confirmation information generated as a result of being encrypted in the first encryption step;
An authentication step of authenticating the external device when it is determined to match by the determination step;
A second input step for inputting second challenge information based on the first challenge information output from the external device in the first output step;
A second encryption step of encrypting the second challenge information input in the second input step using predetermined encryption key information to generate second response information;
A second output step of outputting the second response information generated as a result of encryption by the second encryption step to the external device in order to receive authentication by the external device; Authentication method to use. An authentication method for performing mutual authentication with an external device using a challenge and response method,
A first input step of inputting a random number generated by an external device as first challenge information;
First response information for authenticating from the external device is generated by encrypting a random number as first challenge information input in the first input step using predetermined encryption key information. Encryption process;
A first output step of outputting the first response information generated as a result of encryption by the first encryption step to the external device in order to receive authentication from the external device;
A calculation step of calculating a random number as the first challenge information input in the first input step to generate second challenge information different from the first challenge information;
A second cipher for generating authentication confirmation information used for authentication confirmation for authenticating the external device by encrypting the second challenge information calculated and generated by the calculation step using predetermined encryption key information. Conversion process,
A second output step of outputting to the external device the second challenge information calculated and generated by the calculation step to generate second response information for the external device to receive authentication;
A second input step of inputting the second response information from the external device;
A determination step of determining whether or not the second response information input in the second input step matches the authentication confirmation information generated as a result of encryption in the second encryption step;
An authentication method comprising: an authentication step of authenticating the external device when it is determined to match by the determination step. An input process for inputting the first information and the second information from an external device;
A calculation process for calculating the first information input by the input process to generate third information different from the first information;
An encryption process for generating the fourth information by encrypting the third information calculated and generated by the calculation process using predetermined encryption key information;
An output process in which the external device outputs the third information calculated and generated by the calculation process to generate the second information to the external device;
A determination process for determining whether or not the second information input by the input process and the fourth information generated as a result of encryption by the encryption process match;
A program that causes a computer to execute an authentication process for authenticating the external device when it is determined to match by the determination process, or a computer-readable recording medium that records the program. A program for causing a computer to execute an authenticated process for authenticating from an authentication device using a challenge and response method, or a computer-readable recording medium storing the program,
A random number generation process for generating a random number;
An output process for outputting the random number generated by the random number generation process to the authentication device as random number information;
Input processing for inputting challenge information based on the random number information from the authentication device;
An encryption process for generating response information by encrypting the challenge information input by the input process using predetermined encryption key information;
A program for causing a computer to execute output processing for outputting response information generated as a result of encryption by the encryption processing to the authentication device in order to receive authentication by the authentication device, or a computer readable recording of the program recoding media. A program for causing a computer to execute an authentication process for performing mutual authentication with an external device using a challenge and response method, or a computer-readable recording medium on which the program is recorded,
A random number generation process for generating a random number;
A first output process for outputting the random number generated by the random number generation process to the external device as first challenge information;
A first encryption process for encrypting a random number generated by the random number generation process using predetermined encryption key information to generate authentication confirmation information used for authentication confirmation for authenticating the authentication device;
A first input process for inputting first response information based on the first challenge information for authenticating the external device from the external device;
A determination process for determining whether or not the first response information input by the first input process matches the authentication confirmation information generated as a result of being encrypted by the first encryption process;
An authentication process for authenticating the external device when it is determined to match by the determination process;
A second input process for inputting second challenge information based on the first challenge information output by the first output process from the external device;
A second encryption process for generating second response information by encrypting the second challenge information input by the second input process using predetermined encryption key information;
A program for causing a computer to execute a second output process for outputting the second response information generated as a result of encryption by the second encryption process to the external apparatus in order to receive authentication by the external apparatus, or A computer-readable recording medium on which the program is recorded. A program for causing a computer to execute an authentication process for performing mutual authentication with an external device using a challenge and response method, or a computer-readable recording medium on which the program is recorded,
A first input process for inputting a random number generated by an external device as first challenge information;
First response information for receiving authentication from the external device is generated by encrypting a random number as first challenge information input by the first input process using predetermined encryption key information. Encryption processing,
First output processing for outputting the first response information generated as a result of encryption by the first encryption processing to the external device in order to receive authentication from the external device;
A calculation process for calculating a random number as the first challenge information input by the first input process and generating second challenge information different from the first challenge information;
Second cipher for generating authentication confirmation information used for authentication confirmation for authenticating the external device by encrypting the second challenge information calculated and generated by the arithmetic processing using predetermined encryption key information Processing,
A second output process for outputting the second challenge information calculated and generated by the calculation process to generate second response information for the external apparatus to receive authentication, to the external apparatus;
A second input process for inputting the second response information from the external device;
A determination process for determining whether or not the second response information input by the second input process and the authentication confirmation information generated as a result of encryption by the second encryption process match;
A program that causes a computer to execute an authentication process for authenticating the external device when it is determined to match by the determination process, or a computer-readable recording medium that records the program.

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