JP2004120031A - Identification method - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To enhance a security level in an identification method applied to unlocking/locking of automobile doors. <P>SOLUTION: A key 40 reads an ID code IDCD and random numbers CD0 to CD3 from a fixed value memory 11 and summating an overlap prohibit data OVLP_0 and a random number RND 1 newly creates overlap prohibit data OVLP. Then a random number generator 15 generates authentication purpose random number data RND2 and encrypting the identification purpose random number data RND2 on the basis of the ID code IDCD and the random numbers CD0 to CD3 creates encrypted data CRND2. Then the ID code IDCD, the overlap prohibit data OVLP, the identification purpose random number data RND2, and the encrypted data CRND2 are transmitted to a lock 50. The lock 50 investigates the ID code, the overlap prohibit data, and the random number data on the basis of them and performs authentication only when every investigation indicates normality. <P>COPYRIGHT: (C)2004,JPO

Description

[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention relates to an authentication method suitable for application when unlocking / locking various doors such as an automobile door and a safe door, and when concluding a sales contract through a network.
[0002]
[Prior art]
As this type of authentication method, a one-time password method that can prevent unauthorized acts by “spoofing” of a third party is attracting attention (for example, see Patent Documents 1 and 2).
[0003]
[Patent Document 1] JP-A-2001-352324
[Patent Document 2] JP-A-11-316740
[0004]
[Problems to be solved by the invention]
However, this has the following disadvantages.
[0005]
First, in the method disclosed in Patent Document 1, a counter value which is a parameter at the time of generating a password is advanced based on a random number value within an allowable range, and the authentication side generates and compares the number of passwords within the allowable range. However, there is a problem that many password generation / comparison operations are required.
[0006]
On the other hand, the method disclosed in Patent Document 2 has a disadvantage that time data must be added to the password, so that it can be used only in a device having a clock function.
[0007]
In view of such circumstances, an object of the present invention is to provide an authentication method capable of increasing a security level without the above-described inconvenience.
[0008]
[Means for Solving the Problems]
First, the invention according to claim 1 of the present invention is characterized in that, when performing authentication processing by data communication between a device to be authenticated (10, 40) and an authentication device (20, 50), A fixed value memory (11) and a random number generator (15) are incorporated, and the ID code (IDCD) and the random number (CD0 to CD3) of the device to be authenticated are stored in the fixed value memory in a readable manner. The apparatus reads out the ID code and the random number from the fixed value memory, adds and subtracts the duplication prohibition data (OVLP_0) and the random number (RND1), newly generates duplication prohibition data (OVLP), and uses the random number generator for authentication. Generating random number data (RND2); encrypting the authentication random number data based on the ID code and the random number to generate encrypted data (CRND2); An ID code, duplication prohibition data, authentication random number data, and encrypted data are transmitted to the authentication device, and the authentication device receives the ID code, duplication prohibition data, authentication random number data, and encryption data. The verification is performed on the ID code, the duplication prohibition data and the random number data, and the authentication is performed only when all the verifications are normal. Here, examples of combinations of the device to be authenticated and the authentication device include an authentication code generation device (10) and an authentication server (20), and a key (40) and a lock (50).
[0009]
Further, the invention according to claim 2 of the present invention is characterized in that, when performing authentication processing by data communication between a plurality of devices to be authenticated (10, 40) and the authentication device (20, 50), A fixed value memory (11) and a random number generator (15) are incorporated in the authentication device, and the ID code (IDCD) and the random number (CD0 to CD3) of the device to be authenticated are readably stored in the fixed value memories, respectively. An ID code table (31) in which an ID code corresponding to each of the devices to be authenticated is readably stored is incorporated in the authentication device, and the duplication-inhibited data (OVLP) corresponding to each of the devices to be authenticated is readable. The stored duplication prohibition data table (32) is incorporated in the authentication device, and one of the devices to be authenticated stores an ID code from its fixed value memory. And the random number are read out, the duplication prohibition data (OVLP_0) and the random number (RND1) are added and subtracted to generate new duplication prohibition data (OVLP), and the random number generator generates random number data for authentication (RND2). The random number data for authentication is encrypted based on the ID code and the random number to generate encrypted data (CRND2), and the ID code, the duplication prohibition data, the random number data for authentication, and the encrypted data are transmitted to the authentication device. In response to this, the authentication device verifies the ID code, the duplication prohibition data, and the random number data based on the ID code, the duplication prohibition data, the authentication random number data, and the encrypted data, and all verifications are normal. It is configured to perform authentication only in the case.
[0010]
By adopting these configurations, the ID code is incorporated when encrypting the random number data for authentication in the device to be authenticated. At the time of verification, a triple security check is performed. If at least one of the three types of verification does not pass, the authentication fails.
[0011]
It should be noted that reference numerals in parentheses are for convenience showing corresponding elements in the drawings, and therefore, the present invention is not limited to the description in the drawings. This is the same for the column of “Claims”.
[0012]
BEST MODE FOR CARRYING OUT THE INVENTION
Hereinafter, some embodiments of the authentication method according to the present invention will be described. The method of data encryption / decryption is as shown in FIG.
[0013]
That is, regarding data encryption, the encryption random number generation unit 31 uses a first common key composed of random numbers CD0 to CD3 of predetermined bits (for example, 64 bits) that can be fixed or changed as necessary and predetermined bits. A cryptographic random number RND that cannot be predicted and calculated is generated based on the KEY and the second common key CNT, and the encryption / decryption processing unit 32 generates the cryptographic random number RND and the first common key KEY and the second common key KEY. Based on the key CNT, the source block data BS is encrypted to generate encrypted block data BCS that cannot be predicted and calculated, and the control data generation unit 33 uses the random numbers CD0 to CD3, the first common key KEY, and the second common key KEY. Based on the key CNT, various types of control data used by the encryption random number generation unit 31 and the encryption processing unit 32 are generated.
[0014]
On the other hand, for data decryption, the encryption random number generation unit 31 uses a first common key composed of random numbers CD0 to CD3 of predetermined bits (for example, 64 bits) that can be fixed or changed as necessary and predetermined bits. A cryptographic random number RND that cannot be predicted and calculated is generated based on the KEY and the second common key CNT, and the encryption / decryption processing unit 32 generates the cryptographic random number RND and the first common key KEY and the second common key KEY. Based on the key CNT, the encrypted block data RBCS from the encryption generation device is decrypted to generate block data RBS, and the control data generation unit 33 generates the random numbers CD0 to CD3, the first common key KEY, and the second common key CNT. Based on this, various control data used by the encryption random number generation unit 31 and the encryption processing unit 32 are generated.
[0015]
<First embodiment>
FIG. 2 is a block diagram showing a first embodiment of the authentication method according to the present invention,
FIG. 3 is a flowchart showing an authentication processing program in the authentication system shown in FIG. 2, wherein (a) is a part executed by an authentication code generation device on the authentication side, and (b) is an authentication server on the authentication side. Part to be executed,
FIG. 4 is a diagram showing two examples of an overflow countermeasure in the duplication prohibition processing.
[0016]
As shown in FIG. 2, the authentication system includes a terminal device 2 such as a personal computer connected to a communication network 1 such as the Internet, an authentication code generation device 10 capable of transmitting data to the terminal device 2, and a communication network. 1 and an authentication server 20 connected to the authentication server 1.
[0017]
The authentication code generation device 10 includes a nonvolatile fixed value memory 11, a nonvolatile data memory 12, an adder 13, a random number generator 15, an encryptor 16, and an OTP output unit 17. Stores a predetermined bit (for example, 64 bits) ID code IDCD and four random numbers CD0 to CD3 in a readable manner, and stores in the data memory 12 a predetermined bit (for example, 64 bits) of duplication inhibition data OVLP. Are stored in a readable and writable manner. Here, the random numbers CD0 to CD3 may be fixed, or may be one or more random numbers that can be changed as needed.
[0018]
The authentication server 20 includes a nonvolatile fixed value memory 21, a nonvolatile data memory 22, a first comparator 23, a second comparator 24, a third comparator 25, an encryptor 26, an OTP input unit 27, a verification unit. 28, and a result output unit 29. The fixed value memory 21 stores an ID code IDCD of predetermined bits (for example, 64 bits) and four random numbers CD0 to CD3 in a readable manner, and a data memory. In the area 22, duplication prohibition data OVLP of a predetermined bit (for example, 64 bits) is stored in a readable and writable manner. The ID code IDCD and the random numbers CD0 to CD3 are the same as the ID code IDCD and the random numbers CD0 to CD3 stored in the fixed value memory 11 of the authentication code generation device 10.
[0019]
Since the authentication system has the above-described configuration, when executing the authentication process by the data communication between the authentication code generation device 10 and the authentication server 20, the authentication code generation program PRG1 and the authentication program PRG2 shown in FIG. The following procedure is performed based on the
[0020]
That is, first, in the authentication code generation device 10, the duplication prohibition data OVLP_0 is read from the data memory 12 (step S1 of the authentication code generation program PRG1), and the random number generator 15 generates a random number RND1 of a predetermined bit (for example, 8 bits). Then, the duplication prohibition data OVLP_0 and the random number RND1 are added by the adder 13 to newly generate the duplication prohibition data OVLP (step S3 of the authentication code generation program PRG1). Then, the duplication-inhibited data OVLP is input to the OTP output unit, input to the encryptor as the second encryption key CNT, and further input to the memory 2 for overwriting so that it can be used as the next duplication-inhibited data OVLP. .
[0021]
When the duplication prohibition data OVLP is obtained by adding the random number RND1, the duplication prohibition data OVLP may overflow to the plus side. In this case, as shown in FIG. By moving to the side (for example, when the duplication prohibition data OVLP is 64 bits, OVLP-FFF to FFFh), an overflow of the duplication prohibition data OVLP can be dealt with.
[0022]
On the other hand, the ID code IDCD is read from the fixed value memory 11, and the ID code IDCD is input to the OTP output unit 17 and also to the encryptor 16 as the first encryption key KEY. Further, four random numbers CD0 to CD3 are read from the fixed value memory 11 and input to the encryptor 16 (step S4 of the authentication code generation program PRG1). In addition, random number data RND2 for authentication of predetermined bits (for example, 8 bits) is generated by the random number generator 15, and the random number data RND2 for authentication is input to the OTP output unit 17, and the encryption unit 16 generates the encryption block data BS. (Step S5 of the authentication code generation program PRG1). Then, the block data BS is encrypted using the first encryption key KEY, the second encryption key CNT, and the random numbers CD0 to CD3, and the encrypted data CRND2 is input to the OTP output unit 17 (authentication code generation program PRG1). Step S6).
[0023]
After that, the ID code IDCD, the duplication prohibition data OVLP, the random number data for authentication RND2 and the encrypted data CRND2 are converted from parallel data to serial data by the OTP output unit 17, and then the authentication server via the network 1 via the terminal device 2. 20 (step S7 of the authentication code generation program PRG1).
[0024]
In this way, when the ID code IDCD, the duplication prohibition data OVLP, the random number data for authentication RND2 and the encrypted data CRND2 are transferred from the authentication code generation device 10 to the authentication server 20 in the form of serial data, the authentication server 20 After the serial data is received by the OTP input unit 27 and converted into the original parallel data (step S1 of the authentication program PRG2), three types of verification are performed as described below.
[0025]
First, in order to verify the ID code, the ID code IDCD is read from the OTP input unit 27 and input to the second comparator 24, and the ID code IDCD is read from the fixed value memory 21 and input to the second comparator 24. (Step S2 of the authentication program PRG2), and the two are compared to determine whether they match (Step S3 of the authentication program PRG2). As a result, when they match, it is determined that the data is normal, and the comparison data MATCH is input to the verification unit 28. When they do not match, it is determined that the data is not normal, and the authentication process is stopped.
[0026]
In addition, in order to verify the duplication prohibited data, the duplication prohibited data OVLP is read from the OTP input unit 27 and input to the first comparator 23, and the previous duplication prohibited data OVLP_1 is read from the data memory 22 and the first comparator 23 (step S4 of the authentication program PRG2), and a comparison is made to determine whether the former is greater than the latter (step S5 of the authentication program PRG2). As a result, when the former is larger than the latter, it is determined that the data is normal and the comparison data OVLAP is input to the verification unit 28. When the former is not larger than the latter, it is determined that the data is not normal and the authentication process is stopped. .
[0027]
Further, in order to verify the random number data, the authentication random number data RND2, the ID code IDCD, and the duplication prohibition data OVLP are read from the OTP input unit 27, and the encryption block data BS, the first encryption key KEY, and the second encryption key are respectively read. After inputting the four random numbers CD0 to CD3 from the fixed value memory 21 as the key CNT and inputting them to the encryptor 26, the encryption block data BS is transmitted to the first encryption key KEY and the second encryption key CNT. The encryption is performed using the encryption key CNT and the random numbers CD0 to CD3, and the encrypted data CRND2L is input to the third comparator 25 (step S6 of the authentication program PRG2). On the other hand, the encrypted data CRND2 is read from the OTP input unit 27 and input to the third comparator 25. Then, the two are compared to determine whether or not they match (step S7 of the authentication program PRG2). If they match, it is determined that they are normal, and the comparison data ATTES is input to the verification unit 28, If the two do not match, it is determined that it is not normal and the authentication process is stopped.
[0028]
When the verification unit 28 receives these three types of comparison data MATCH, OVLAP, and ATTES, it determines that the verification is normal in all verifications, overwrites the current duplication prohibition data OVLP in the data memory 22, and writes the result. The verification data is output to the output unit 29 (step S8 of the authentication program PRG2), and upon receiving the verification data, the result output unit 29 executes a predetermined process (step S9 of the authentication program PRG2). Here, the authentication processing ends.
[0029]
As described above, since the ID code IDCD is also incorporated when the block data BS is encrypted by the authentication code generation device 10, even if the other embedded data, that is, the second encryption key CNT and the random numbers CD0 to CD3 are the same, the encrypted data is encrypted. CRND2 will be different. In addition, when the verification is performed by the authentication server 20, a triple security check is performed. If at least one of the three types of verification does not pass, the authentication fails. As a result, unauthorized decryption by a third party becomes difficult, and the security level is improved.
[0030]
Moreover, unlike the conventional one-time password method in which the counter value which is a parameter at the time of password generation is advanced based on a random value within an allowable range, there is no problem that a large number of password generation / comparison operations are required, and Unlike a conventional one-time password method in which time data is added to a password, it can be used even in a device without a clock function.
[0031]
<Second embodiment>
In the first embodiment described above, when the authentication server 20 verifies the random number data, the encryption data CRND2L obtained by encrypting the authentication random number data RND2 from the OTP input unit 27 by the encryptor 26 and the OTP input The case where the encrypted data CRND2 from the unit 27 is compared with the third comparator 25 has been described, but as shown in FIG. 5, a decryptor 30 is provided in the authentication server 20 instead of the encryptor 26, and the OTP The encrypted data CRND2 from the input unit 27 may be decrypted by the decoder 30, and the decrypted data may be compared with the random number data for authentication RND2 from the OTP input unit 27.
[0032]
<Third embodiment>
In the above-described first embodiment, a case has been described where the calculation method of adding the random number RND1 to the duplication prohibition data OVLP_0 by the adder 13 is used to newly calculate the duplication prohibition data OVLP in the authentication code generation device 10. As shown in FIG. 6, a subtractor 14 is provided in the authentication code generation device 10 instead of the adder 13, and when the duplication inhibition data OVLP is newly calculated, the subtractor 14 generates a random number RND1 from the duplication inhibition data OVLP_0. You can also pull it. In this case, when the authentication server 20 verifies the duplication prohibition data, when the duplication prohibition data OVLP read from the OTP input unit 27 is compared with the previous duplication prohibition data OVLP_1 read from the data memory 22, the former is the latter. It is determined whether the former is smaller than the latter. If the former is smaller than the latter, it is determined that it is normal and the comparison data OVLAP is input to the verification unit 28. If the former is not smaller than the latter, it is determined that it is not normal. Authentication process is stopped.
[0033]
Similarly, in the above-described second embodiment, the duplication inhibition data OVLP can be newly calculated by subtraction instead of addition.
[0034]
In addition, when the duplication prohibition data OVLP is obtained by subtraction of the random number RND1, the duplication prohibition data OVLP may overflow to the minus side. In this case, as shown in FIG. By moving to the side (for example, when the duplication inhibition data OVLP is 64 bits, OVLP + FFF to FFFh), it is possible to cope with the overflow of the duplication inhibition data OVLP.
[0035]
<Fourth embodiment>
In the above-described first to third embodiments, the case where one authentication code generation device 10 and one authentication server 20 correspond one-to-one has been described. One authentication server 20 is associated with many-to-one, one authentication code generation device 10 is associated with a plurality of authentication servers 20 on a one-to-many basis, and a plurality of authentication code generation devices 10 are associated with one authentication server 20. It is also possible to associate a plurality of authentication servers 20 in many-to-many correspondence.
[0036]
Hereinafter, as a fourth embodiment, a case will be described in which a plurality of authentication code generation devices 10 correspond to one authentication server 20 in a many-to-one correspondence, but in other cases (one-to-many, many-to-many). The same applies to ()).
FIG. 7 is a block diagram showing a fourth embodiment of the authentication method according to the present invention,
FIG. 8 is a flowchart showing an authentication processing program in the authentication system shown in FIG. 7, wherein (a) is a part executed by the authentication code generation device on the authentication side, and (b) is an authentication server on the authentication side. This is the part that is executed.
[0037]
As shown in FIG. 7, this authentication system transmits a plurality of (three in FIG. 7) personal computers and other terminal devices 2 connected to a communication network 1 such as the Internet, and transmits data to these terminal devices 2. It comprises the same number (three in FIG. 7) of authentication code generation devices 10 as possible and an authentication server 20 connected to the communication network 1.
[0038]
Each authentication code generation device 10 includes a nonvolatile fixed value memory 11, a nonvolatile data memory 12, an adder 13, a random number generator 15, an encryptor 16, and an OTP output unit 17. 11 stores an ID code IDCD of a predetermined bit (for example, 64 bits) and four random numbers CD0 to CD3 in a readable manner, and a data memory 12 of a predetermined bit (for example, 64 bits) The OVLP is stored readable and writable. Here, the random numbers CD0 to CD3 may be fixed, or may be one or more random numbers that can be changed as needed.
[0039]
The authentication server 20 includes a nonvolatile fixed value memory 21, an ID code table 31, a duplication prohibition data table 32, a first comparator 23, a second comparator 24, a third comparator 25, an encryptor 26, and an OTP input unit. 27, a verification unit 28, a result output unit 29, and a search control unit 34. The fixed value memory 21 stores four random numbers CD0 to CD3 in a readable manner. Further, an ID code IDCD of a predetermined bit (for example, 64 bits) is stored in the ID code table 31 so as to be readable in a form corresponding to all the authentication code generation devices 10. (For example, 64 bits) duplication prohibition data OVLP is stored in such a manner as to be readable and writable in a form compatible with all the authentication code generation devices 10. The ID code IDCD and the random numbers CD0 to CD3 are the same as the ID code IDCD and the random numbers CD0 to CD3 stored in the fixed value memory 11 of each authentication code generation device 10.
[0040]
Since the authentication system has the above-described configuration, the authentication code generation program PRG3 and the authentication code generation program PRG3 shown in FIG. The following procedure is performed based on the program PRG4.
[0041]
First, in the authentication code generation device 10, the duplication prohibition data OVLP_0 is read from the data memory 12 (step S1 of the authentication code generation program PRG3), and a random number RND1 of a predetermined bit (for example, 8 bits) is generated by the random number generator 15. Then, the duplication prohibition data OVLP_0 and the random number RND1 are added by the adder 13 to newly generate the duplication prohibition data OVLP (step S3 of the authentication code generation program PRG3). Then, the duplication-inhibited data OVLP is input to the OTP output unit, input to the encryptor as the second encryption key CNT, and further input to the memory 2 for overwriting so that it can be used as the next duplication-inhibited data OVLP. .
[0042]
When the duplication prohibition data OVLP is obtained by adding the random number RND1, the duplication prohibition data OVLP may overflow to the plus side. In this case, as shown in FIG. By moving to the side (for example, when the duplication prohibition data OVLP is 64 bits, OVLP-FFF to FFFh), an overflow of the duplication prohibition data OVLP can be dealt with.
[0043]
On the other hand, the ID code IDCD is read from the fixed value memory 11, and the ID code IDCD is input to the OTP output unit 17 and also to the encryptor 16 as the first encryption key KEY. Further, four random numbers CD0 to CD3 are read from the fixed value memory 11 and input to the encryptor 16 (step S4 of the authentication code generation program PRG3). In addition, random number data RND2 for authentication of predetermined bits (for example, 8 bits) is generated by the random number generator 15, and the random number data RND2 for authentication is input to the OTP output unit 17, and the encryption unit 16 generates the encryption block data BS. (Step S5 of the authentication code generation program PRG3). Then, the block data BS is encrypted using the first encryption key KEY, the second encryption key CNT, and the random numbers CD0 to CD3, and the encrypted data CRND2 is input to the OTP output unit 17 (authentication code generation program PRG3). Step S6).
[0044]
After that, the ID code IDCD, the duplication prohibition data OVLP, the random number data for authentication RND2 and the encrypted data CRND2 are converted from parallel data to serial data by the OTP output unit 17, and then the authentication server via the network 1 via the terminal device 2. 20 (step S7 of the authentication code generation program PRG3).
[0045]
In this way, when the ID code IDCD, the duplication prohibition data OVLP, the random number data for authentication RND2 and the encrypted data CRND2 are transferred from the authentication code generation device 10 to the authentication server 20 in the form of serial data, the authentication server 20 After the serial data is received by the OTP input unit 27 and converted into the original parallel data (step S1 of the authentication program PRG4), three types of verification are performed as described below.
[0046]
First, in order to verify the ID code, the ID code IDCD is read from the OTP input unit 27 and input to the second comparator 24. On the other hand, the search control unit 34 performs an inquiry of the ID code IDCD until the number of searches reaches a predetermined maximum value. That is, after initializing the search address (step S3 of the authentication program PRG4), the ID code IDCD at the address obtained by adding "1" to the search address is read from the ID code table 31 and input to the second comparator 24 ( Step S4 of the authentication program PRG4). Then, the two are compared to determine whether they match (step S5 of the authentication program PRG4). If they match, it is determined to be normal and the comparison data MATCH is input to the verification unit 28. If they do not match, it is determined whether or not the number of searches has reached the maximum value (step S6 of the authentication program PRG4). If the number of searches has not reached the maximum value, "1" is set to the search address. After the addition, the comparison of the ID code IDCD is performed in the same manner. If the number of searches reaches the maximum value, it is determined that the search is not normal and the authentication process is stopped.
[0047]
In addition, in order to verify the duplication prohibition data, the duplication prohibition data OVLP_1 is read from the OTP input unit 27 and input to the first comparator 23, and the previous duplication prohibition data OVLP_1 corresponding to the search address whose ID code IDCD matches. Is read from the duplication prohibition data table 32 and input to the first comparator 23 (step S7 of the authentication program PRG4), and the two are compared to determine whether the former is greater than the latter (step S8 of the authentication program PRG4). . As a result, when the former is larger than the latter, it is determined that the data is normal and the comparison data OVLAP is input to the verification unit 28. When the former is not larger than the latter, it is determined that the data is not normal and the authentication process is stopped. .
[0048]
Further, in order to verify the random number data, the authentication random number data RND2, the ID code IDCD, and the duplication prohibition data OVLP are read from the OTP input unit 27, and the encryption block data BS, the first encryption key KEY, and the second encryption key are respectively read. After inputting the random number CD0 to CD3 from the fixed value memory 21 as the key CNT and reading the four random numbers CD0 to CD3 into the encryptor 26 (step S2 of the authentication program PRG4), the encryption block data BS is transmitted to the The first encryption key KEY, the second encryption key CNT, and the random numbers CD0 to CD3 are used for encryption, and the encrypted data CRND2L is input to the third comparator 25 (step S9 of the authentication program PRG4). On the other hand, the encrypted data CRND2 is read from the OTP input unit 27 and input to the third comparator 25. Then, the two are compared to determine whether or not they match (Step S10 of the authentication program PRG4). If they match, it is determined that they are normal, and the comparison data ATTES is input to the verification unit 28, If the two do not match, it is determined that it is not normal and the authentication process is stopped.
[0049]
When the verification unit 28 receives these three types of comparison data MATCH, OVLAP, and ATTES, it determines that the verification is normal in all verifications, and overwrites the current duplication prohibition data OVLP on the duplication prohibition data table 32. The verification data is output to the result output unit 29 (step S11 of the authentication program PRG4). Upon receiving the verification data, the result output unit 29 executes a predetermined process (step S12 of the authentication program PRG4). Here, the authentication processing ends.
[0050]
As described above, since the ID code IDCD is also incorporated when the block data BS is encrypted by the authentication code generation device 10, even if the other embedded data, that is, the second encryption key CNT and the random numbers CD0 to CD3 are the same, the encrypted data is encrypted. CRND2 will be different. In addition, when the verification is performed by the authentication server 20, a triple security check is performed. If at least one of the three types of verification does not pass, the authentication fails. As a result, unauthorized decryption by a third party becomes difficult, and the security level is improved.
[0051]
Moreover, unlike the conventional one-time password method in which the counter value which is a parameter at the time of password generation is advanced based on a random value within an allowable range, there is no problem that a large number of password generation / comparison operations are required, and Unlike a conventional one-time password method in which time data is added to a password, it can be used even in a device without a clock function.
[0052]
<Fifth embodiment>
In each of the above-described embodiments, the case has been described where the authentication code generation device 10 is employed as the device to be authenticated and the authentication server 20 is employed as the authentication device. It is also possible. Hereinafter, as a fifth embodiment, a case will be described in which a key is adopted as a device to be authenticated and a lock is adopted as an authentication device.
FIG. 9 is a block diagram showing a fifth embodiment of the authentication method according to the present invention,
10 is a flowchart showing an authentication processing program in the authentication system shown in FIG. 9, wherein (a) is a part executed by a key to be authenticated, and (b) is a part executed by a lock to be authenticated. It is.
[0053]
As shown in FIG. 9, the authentication system includes a lock 50 and a key 40 capable of transmitting data to the lock 50 by infrared communication or the like.
[0054]
The key 40 includes a nonvolatile fixed value memory 11, a nonvolatile data memory 12, an adder 13, a random number generator 15, an encryptor 16, and a transmitting unit 19. An ID code IDCD (for example, 64 bits) and four random numbers CD0 to CD3 are stored in a readable manner, and a predetermined bit (for example, 64 bits) duplication-inhibited data OVLP is readable and writable in the data memory 12. Is stored in Here, the random numbers CD0 to CD3 may be fixed, or may be one or more random numbers that can be changed as needed.
[0055]
The lock 50 is composed of a nonvolatile fixed value memory 21, a nonvolatile data memory 22, a first comparator 23, a second comparator 24, a third comparator 25, an encryptor 26, a receiving unit 33, a verification unit 28, The fixed value memory 21 stores an ID code IDCD of predetermined bits (for example, 64 bits) and four random numbers CD0 to CD3 in a readable manner. Indicates a predetermined bit (for example, 64 bits) of duplication prohibition data OVLP that is readable and writable. The ID code IDCD and the random numbers CD0 to CD3 are the same as the ID code IDCD and the random numbers CD0 to CD3 stored in the fixed value memory 11 of the key 40.
[0056]
Since the authentication system has the above-described configuration, when performing the authentication process by data communication between the key 40 and the lock 50, the following process is performed based on the authentication code generation program PRG5 and the authentication program PRG6 shown in FIG. Is performed in the following procedure.
[0057]
That is, first, in the key 40, the duplication prohibition data OVLP_0 is read from the data memory 12 (step S1 of the authentication code generation program PRG5), and a random number RND1 of a predetermined bit (for example, 8 bits) is generated by the random number generator 15 (authentication). The duplication prohibition data OVLP_0 and the random number RND1 are added by the adder 13 to newly generate the duplication prohibition data OVLP (step S3 of the authentication code generation program PRG5). Then, this duplication-inhibited data OVLP is input to the transmission unit 19, and is also input to the encryptor 16 as the second encryption key CNT, and is further input to the data memory 12 so as to be used as the next duplication-inhibited data OVLP. Write.
[0058]
When the duplication prohibition data OVLP is obtained by adding the random number RND1, the duplication prohibition data OVLP may overflow to the plus side. In this case, as shown in FIG. By moving to the side (for example, when the duplication prohibition data OVLP is 64 bits, OVLP-FFF to FFFh), an overflow of the duplication prohibition data OVLP can be dealt with.
[0059]
On the other hand, the ID code IDCD is read from the fixed value memory 11, and the ID code IDCD is input to the transmission unit 19 and also to the encryptor 16 as the first encryption key KEY. Further, four random numbers CD0 to CD3 are read from the fixed value memory 11 and input to the encryptor 16 (step S4 of the authentication code generation program PRG5). In addition, random number data RND2 for authentication of predetermined bits (for example, 8 bits) is generated by the random number generator 15, and the random number data RND2 for authentication is input to the transmission unit 19, and is also transmitted to the encryptor 16 as block data BS for encryption. Input (Step S5 of the authentication code generation program PRG5). Then, the block data BS is encrypted using the first encryption key KEY, the second encryption key CNT, and the random numbers CD0 to CD3, and the encrypted data CRND2 is input to the transmission unit 19 (the authentication code generation program PRG5). Step S6).
[0060]
After that, the transmission unit 19 converts the ID code IDCD, the duplication prohibition data OVLP, the authentication random number data RND2 and the encrypted data CRND2 from parallel data to serial data, and then transfers them to the lock 50 (step of the authentication code generation program PRG5). S7).
[0061]
In this way, when the ID code IDCD, the duplication prohibition data OVLP, the random number data for authentication RND2 and the encrypted data CRND2 are transferred from the key 40 to the lock 50 in the form of serial data, the lock 50 receives the serial data. After being received by the unit 33 and converted into the original parallel data (step S1 of the authentication program PRG6), three types of verification are performed as described below.
[0062]
First, in order to verify the ID code, the ID code IDCD is read from the receiving unit 33 and input to the second comparator 24, and the ID code IDCD is read from the fixed value memory 21 and input to the second comparator 24 ( Step S2 of the authentication program PRG6, the two are compared to determine whether they match (step S3 of the authentication program PRG6). As a result, when they match, it is determined that the data is normal, and the comparison data MATCH is input to the verification unit 28. When they do not match, it is determined that the data is not normal, and the authentication process is stopped.
[0063]
Further, in order to verify the duplication-prohibited data, the duplication-prohibition data OVLP is read from the receiving unit 33 and input to the first comparator 23, and the previous duplication-prohibition data OVLP_1 is read from the data memory 22 to read the first comparator 23 (Step S4 of the authentication program PRG6), and a comparison is made to determine whether the former is greater than the latter (Step S5 of the authentication program PRG6). As a result, when the former is larger than the latter, it is determined that the data is normal and the comparison data OVLAP is input to the verification unit 28. When the former is not larger than the latter, it is determined that the data is not normal and the authentication process is stopped. .
[0064]
Further, in order to verify the random number data, the authentication random number data RND2, the ID code IDCD, and the duplication prohibition data OVLP are read from the receiving unit 33, and the encryption block data BS, the first encryption key KEY, and the second encryption key are respectively read. After inputting the random numbers CD0 to CD3 from the fixed-value memory 21 as the CNT and inputting the random numbers CD0 to CD3 from the fixed value memory 21 to the encryptor 26, the encryption block data BS is transmitted to the first encryption key KEY and the second encryption key. It encrypts using the use key CNT and the random numbers CD0 to CD3, and inputs the encrypted data CRND2L to the third comparator 25 (step S6 of the authentication program PRG6). On the other hand, the encrypted data CRND2 is read from the receiving unit 33 and input to the third comparator 25. Then, the two are compared to determine whether or not they match (step S7 of the authentication program PRG6). If they match, it is determined that they are normal, and the comparison data ATTES is input to the verification unit 28, If the two do not match, it is determined that it is not normal and the authentication process is stopped.
[0065]
When the verification unit 28 receives these three types of comparison data MATCH, OVLAP, and ATTES, it determines that the verification is normal in all verifications, overwrites the current duplication prohibition data OVLP in the data memory 22, and opens and closes the data. The verification data is output to the control unit 35 (step S8 of the authentication program PRG6), and in response to the verification data, the opening / closing control unit 35 executes a predetermined process (for example, unlocking of an automobile door) (the authentication program PRG6 is executed). Step S9). Here, the authentication processing ends.
[0066]
As described above, when the block data BS is encrypted with the key 40, the ID code IDCD is also incorporated. Therefore, even if the other embedded data, that is, the second encryption key CNT and the random numbers CD0 to CD3 are the same, the encrypted data CRND2 is different. Will be. When performing verification with the lock 50, a triple security check is performed. If at least one of the three types of verification does not pass, the authentication fails. As a result, unauthorized decryption by a third party becomes difficult, and the security level is improved.
[0067]
Moreover, unlike the conventional one-time password method in which the counter value which is a parameter at the time of password generation is advanced based on a random value within an allowable range, there is no problem that a large number of password generation / comparison operations are required, and Unlike a conventional one-time password method in which time data is added to a password, it can be used even in a device without a clock function.
[0068]
<Sixth embodiment>
In the fifth embodiment described above, when verifying the random number data with the lock 50, the encryption data CRND2L obtained by encrypting the authentication random number data RND2 from the receiving unit 33 with the encryptor 26, In the above description, the third comparator 25 compares the encrypted data CRND2 with the encrypted data CRND2. However, the decryptor 30 is provided in the lock 50 instead of the encryptor 26 as shown in FIG. The encrypted data CRND2 may be decrypted by the decryptor 30 and compared with the random number data for authentication RND2 from the receiving unit 33.
[0069]
<Seventh embodiment>
In the fifth embodiment described above, a case has been described in which a calculation method of adding a random number RND1 to the duplication prohibition data OVLP_0 by the adder 13 to newly calculate the duplication prohibition data OVLP with the key 40 is described. As shown in (1), a subtractor 14 may be provided in the key 40 instead of the adder 13, and the subtractor 14 may subtract the random number RND1 from the duplication prohibition data OVLP_0 when newly calculating the duplication prohibition data OVLP. Absent. In this case, when verifying the duplication-inhibited data with the lock 50, when comparing the duplication-inhibited data OVLP read from the receiving unit 33 with the previous duplication-inhibited data OVLP_1 read from the data memory 22, the former is smaller than the latter. If the former is smaller than the latter, it is determined that it is normal and the comparison data OVLAP is input to the verification unit 28. If the former is not smaller than the latter, it is determined that it is not normal and the authentication is performed. Processing will be stopped.
[0070]
Similarly, in the above-described sixth embodiment, the duplication inhibition data OVLP can be newly calculated by subtraction instead of addition.
[0071]
In addition, when the duplication prohibition data OVLP is obtained by subtraction of the random number RND1, the duplication prohibition data OVLP may overflow to the minus side. In this case, as shown in FIG. By moving to the side (for example, when the duplication inhibition data OVLP is 64 bits, OVLP + FFF to FFFh), it is possible to cope with the overflow of the duplication inhibition data OVLP.
[0072]
<Eighth embodiment>
In the above-described fifth to seventh embodiments, a case has been described where one key 40 and one lock 50 correspond one-to-one, but a plurality of keys 40 and one lock 50 are Many-to-one correspondence, one key 40 and a plurality of locks 50 are made one-to-many correspondence, and a plurality of keys 40 and a plurality of locks 50 are made many-to-many correspondence. It is also possible.
[0073]
Hereinafter, as the eighth embodiment, a case will be described in which a plurality of keys 40 and one lock 50 correspond in many-to-one correspondence. However, the same applies to other cases (one-to-many, many-to-many). It is.
FIG. 13 is a block diagram showing an eighth embodiment of the authentication method according to the present invention,
14 is a flowchart showing an authentication processing program in the authentication system shown in FIG. 13, wherein (a) is a part executed by a key to be authenticated, and (b) is a part executed by a lock to be authenticated. It is.
[0074]
As shown in FIG. 13, this authentication system includes a lock 50 and a plurality (three in FIG. 13) of keys 40 capable of transmitting data to the lock 50 by infrared communication or the like.
[0075]
Each key 40 includes a non-volatile fixed value memory 11, a non-volatile data memory 12, an adder 13, a random number generator 15, an encryptor 16, and a transmission unit 19. A bit (for example, 64 bits) ID code IDCD and four random numbers CD0 to CD3 are stored in a readable manner, and a predetermined bit (for example, 64 bits) duplication-inhibited data OVLP is read and written in the data memory 12. It is stored freely. Here, the random numbers CD0 to CD3 may be fixed, or may be one or more random numbers that can be changed as needed.
[0076]
The lock 50 includes a nonvolatile fixed value memory 21, an ID code table 31, a duplication prohibition data table 32, a first comparator 23, a second comparator 24, a third comparator 25, an encryptor 26, a receiving unit 33, The fixed value memory 21 includes a verification unit 28, an opening / closing control unit 35, and a search control unit 34. The fixed value memory 21 stores four random numbers CD0 to CD3. Further, an ID code IDCD of a predetermined bit (for example, 64 bits) is stored in the ID code table 31 so as to be readable in a form corresponding to all the keys 40, and a predetermined bit (for example, 64 bits) is stored in the duplication prohibition data table 32. (64 bits) duplication prohibition data OVLP is stored readable and writable in a form corresponding to all keys 40. The ID code IDCD and the random numbers CD0 to CD3 are the same as the ID code IDCD and the random numbers CD0 to CD3 stored in the fixed value memory 11 of each key 40.
[0077]
Since the authentication system has the above-described configuration, the authentication process based on the authentication code generation program PRG7 and the authentication program PRG8 shown in FIG. The following procedure is performed.
[0078]
First, with the key 40, the duplication prohibition data OVLP_0 is read from the data memory 12 (step S1 of the authentication code generation program PRG7), and a random number RND1 of a predetermined bit (for example, 8 bits) is generated by the random number generator 15 (authentication). Step S2 of the code generation program PRG7), the duplication prohibition data OVLP_0 and the random number RND1 are added by the adder 13 to newly generate duplication prohibition data OVLP (step S3 of the authentication code generation program PRG7). Then, this duplication-inhibited data OVLP is input to the transmission unit 19, and is also input to the encryptor 16 as the second encryption key CNT, and is further input to the data memory 12 so as to be used as the next duplication-inhibited data OVLP. Write.
[0079]
When the duplication prohibition data OVLP is obtained by adding the random number RND1, the duplication prohibition data OVLP may overflow to the plus side. In this case, as shown in FIG. By moving to the side (for example, when the duplication prohibition data OVLP is 64 bits, OVLP-FFF to FFFh), an overflow of the duplication prohibition data OVLP can be dealt with.
[0080]
On the other hand, the ID code IDCD is read from the fixed value memory 11, and the ID code IDCD is input to the transmission unit 19 and also to the encryptor 16 as the first encryption key KEY. Further, four random numbers CD0 to CD3 are read from the fixed value memory 11 and input to the encryptor 16 (step S4 of the authentication code generation program PRG7). In addition, random number data RND2 for authentication of predetermined bits (for example, 8 bits) is generated by the random number generator 15, and the random number data RND2 for authentication is input to the transmission unit 19, and is also transmitted to the encryptor 16 as block data BS for encryption. Input (Step S5 of the authentication code generation program PRG7). Then, the block data BS is encrypted using the first encryption key KEY, the second encryption key CNT, and the random numbers CD0 to CD3, and the encrypted data CRND2 is input to the transmission unit 19 (the authentication code generation program PRG7). Step S6).
[0081]
Thereafter, the transmitting unit 19 converts the ID code IDCD, the duplication prohibition data OVLP, the authentication random number data RND2, and the encrypted data CRND2 from parallel data to serial data, and then transfers them to the lock 50 (step of the authentication code generation program PRG7). S7).
[0082]
In this way, when the ID code IDCD, the duplication prohibition data OVLP, the random number data for authentication RND2 and the encrypted data CRND2 are transferred from the key 40 to the lock 50 in the form of serial data, the lock 50 receives the serial data. After being received by the unit 33 and converted into the original parallel data (step S1 of the authentication program PRG8), three types of verification are performed as described below.
[0083]
First, in order to verify the ID code, the ID code IDCD is read from the receiving unit 33 and input to the second comparator 24. On the other hand, the search control unit 34 performs an inquiry of the ID code IDCD until the number of searches reaches a predetermined maximum value. That is, after initializing the search address (step S3 of the authentication program PRG8), the ID code IDCD at the address obtained by adding “1” to the search address is read from the ID code table 31 and input to the second comparator 24 ( Step S4 of the authentication program PRG8). Then, the two are compared to determine whether or not they match (step S5 of the authentication program PRG8). If they match, it is determined to be normal and the comparison data MATCH is input to the verification unit 28. If they do not match, it is determined whether or not the number of searches has reached the maximum value (step S6 of the authentication program PRG8). If the number of searches has not reached the maximum value, "1" is set to the search address. After the addition, the ID code IDCD is compared in the same manner. If the number of searches reaches the maximum value, it is determined that the search is not normal and the authentication process is stopped.
[0084]
Further, in order to verify the duplication-prohibited data, the duplication-prohibition data OVLP is read from the receiving unit 33 and input to the first comparator 23, and the previous duplication-prohibition data OVLP_1 corresponding to the search address whose ID code IDCD matches is read. The data is read from the duplication prohibition data table 32 and input to the first comparator 23 (step S7 of the authentication program PRG8), and the two are compared to determine whether the former is greater than the latter (step S8 of the authentication program PRG8). As a result, when the former is larger than the latter, it is determined that the data is normal and the comparison data OVLAP is input to the verification unit 28. When the former is not larger than the latter, it is determined that the data is not normal and the authentication process is stopped. .
[0085]
Further, in order to verify the random number data, the authentication random number data RND2, the ID code IDCD, and the duplication prohibition data OVLP are read from the receiving unit 33, and the encryption block data BS, the first encryption key KEY, and the second encryption key are respectively read. After inputting the random numbers CD0 to CD3 from the fixed value memory 21 as the CNT and inputting them to the encryptor 26 (step S2 of the authentication program PRG8), the encryption block data BS is stored in the first value. The encryption is performed using the encryption key KEY, the second encryption key CNT, and the random numbers CD0 to CD3, and the encrypted data CRND2L is input to the third comparator 25 (step S9 of the authentication program PRG8). On the other hand, the encrypted data CRND2 is read from the receiving unit 33 and input to the third comparator 25. Then, the two are compared to determine whether or not they match (step S10 of the authentication program PRG8). If they match, it is determined that they are normal and the comparison data ATTES is input to the verification unit 28, If the two do not match, it is determined that it is not normal and the authentication process is stopped.
[0086]
When the verification unit 28 receives these three types of comparison data MATCH, OVLAP, and ATTES, it determines that the verification is normal in all verifications, and overwrites the current duplication prohibition data OVLP on the duplication prohibition data table 32. The verification data is output to the opening / closing control unit 35 (step S11 of the authentication program PRG8), and upon receiving the verification data, the opening / closing control unit 35 executes a predetermined process (step S12 of the authentication program PRG8). Here, the authentication processing ends.
[0087]
As described above, when the block data BS is encrypted with the key 40, the ID code IDCD is also incorporated. Therefore, even if the other embedded data, that is, the second encryption key CNT and the random numbers CD0 to CD3 are the same, the encrypted data CRND2 is different. Will be. When performing verification with the lock 50, a triple security check is performed. If at least one of the three types of verification does not pass, the authentication fails. As a result, unauthorized decryption by a third party becomes difficult, and the security level is improved.
[0088]
Moreover, unlike the conventional one-time password method in which the counter value which is a parameter at the time of password generation is advanced based on a random value within an allowable range, there is no problem that a large number of password generation / comparison operations are required, and Unlike a conventional one-time password method in which time data is added to a password, it can be used even in a device without a clock function.
[0089]
【The invention's effect】
As described above, according to the first and second aspects of the present invention, the ID code is incorporated when the authentication random number data is encrypted by the device to be authenticated. In addition to the difference in the encrypted data, a triple security check is performed at the time of verification by the authentication device. If at least one of the three types of verification does not pass, the authentication fails. It is possible to provide an authentication method capable of increasing the security level without inconvenience associated with the one-time password method.
[Brief description of the drawings]
FIG. 1 is a block diagram showing a procedure of encryption / decryption.
FIG. 2 is a block diagram showing a first embodiment of an authentication method according to the present invention.
3 is a flowchart showing an authentication processing program in the authentication system shown in FIG. 2, wherein (a) is a part executed by an authentication code generation device on the authentication side, and (b) is an authentication server on the authentication side; This is the part that is executed.
FIG. 4 is a diagram illustrating two examples of an overflow countermeasure method in the duplication prohibition processing.
FIG. 5 is a block diagram showing a second embodiment of the authentication method according to the present invention.
FIG. 6 is a block diagram showing a third embodiment of the authentication method according to the present invention.
FIG. 7 is a block diagram showing a fourth embodiment of the authentication method according to the present invention.
8 is a flowchart showing an authentication processing program in the authentication system shown in FIG. 7, in which (a) is a part executed by an authentication code generation device on the authenticated side, and (b) is an authentication server on the authenticated side; This is the part that is executed.
FIG. 9 is a block diagram showing a fifth embodiment of the authentication method according to the present invention.
10 is a flowchart showing an authentication processing program in the authentication system shown in FIG. 9, wherein (a) is a part executed by a key to be authenticated, and (b) is executed by a lock to be authenticated. Part.
FIG. 11 is a block diagram showing a sixth embodiment of the authentication method according to the present invention.
FIG. 12 is a block diagram showing a seventh embodiment of the authentication method according to the present invention.
FIG. 13 is a block diagram showing an eighth embodiment of the authentication method according to the present invention.
14 is a flowchart showing an authentication processing program in the authentication system shown in FIG. 13, wherein (a) is a part executed by a key to be authenticated, and (b) is a part executed by a lock to be authenticated. Part.
[Explanation of symbols]
10 Authentication code generation device (device to be authenticated)
11: Fixed value memory
15 Random number generator
20 Authentication server (authentication device)
31 ID code table
32: Duplicate prohibition data table
40 key (device to be authenticated)
50: Lock (authentication device)
IDCD ... ID code
CD0-CD3: random numbers
OVLP_0, OVLP... Duplicate prohibited data
RND2: Random number data for authentication
CRND2: Encrypted data

Claims (2)

When performing the authentication process by data communication between the device to be authenticated (10, 40) and the authentication device (20, 50),
A fixed value memory (11) and a random number generator (15) are incorporated in the device to be authenticated,
An ID code (IDCD) and a random number (CD0 to CD3) of the device to be authenticated are readably stored in the fixed value memory,
The device to be authenticated reads out an ID code and a random number from the fixed value memory, adds and subtracts the duplication prohibition data (OVLP_0) and the random number (RND1) to newly generate duplication prohibition data (OVLP), Generates random number data for authentication (RND2), and encrypts the random number data for authentication based on the ID code and the random number to generate encrypted data (CRND2). Transmitting random number data and encrypted data to the authentication device,
In response to this, the authentication device verifies the ID code, the duplication prohibition data, and the random number data based on the ID code, the duplication prohibition data, the authentication random number data, and the encrypted data, and when all verifications are normal. An authentication method characterized in that authentication is performed only for a user. When performing authentication processing by data communication between the plurality of devices to be authenticated (10, 40) and the authentication devices (20, 50),
A fixed value memory (11) and a random number generator (15) are incorporated in each of the devices to be authenticated,
An ID code (IDCD) and a random number (CD0 to CD3) of the device to be authenticated are readably stored in the fixed value memories, respectively.
An ID code table (31) in which an ID code corresponding to each of the devices to be authenticated is readably stored is incorporated in the authentication device, and duplication prohibition data (OVLP) corresponding to each of the devices to be authenticated is readably stored. The duplication prohibition data table (32) obtained is incorporated in the authentication device,
One of the devices to be authenticated reads an ID code and a random number from the fixed value memory, adds and subtracts the duplication prohibition data (OVLP_0) and the random number (RND1) to newly generate duplication prohibition data (OVLP), A random number generator generates random number data for authentication (RND2), and encrypts the random number data for authentication based on the ID code and the random number to generate encrypted data (CRND2). Transmitting authentication random number data and encrypted data to the authentication device,
In response to this, the authentication device verifies the ID code, the duplication prohibition data, and the random number data based on the ID code, the duplication prohibition data, the authentication random number data, and the encrypted data, and when all verifications are normal. An authentication method characterized in that authentication is performed only for a user.

Images