KR102282855B1 - Authentication device including a plurality of puf chips - Google Patents

Abstract

Disclosed is an authentication device including a plurality of physical unclonable function (PUF) chips to reinforce security performance. According to the present invention, the authentication device comprises a plurality of PUF chips outputting different response data to the same challenge data. The authentication device selects at least one PUF chip from among the plurality of PUF chips according to an authentication information generation rule shared with a server and generates PUF authentication information by using response data at the time when the challenge data is input to the selected PUF chip. The PUF authentication information can used to extract an authentication result through comparison with server authentication information generated by the server according to the same authentication information generation rule as an authentication information generation rule used to generate the PUF authentication information.

Description

AUTHENTICATION DEVICE INCLUDING A PLURALITY OF PUF CHIPS

The present invention relates to an authentication device including a plurality of Physical Unclonable Function (PUF) chips that output different response data to the same challenge data, and an authentication method using the same.

Existing software-based security proceeds by storing the key in non-volatile memory (NVM), but the digital key stored in the NVM is vulnerable to security as the algorithm hacking speed using physical attacks accelerates. There are disadvantages. To overcome this, “Physical Unclonable Function (PUF)”, a kind of hardware-based security method that generates unique volatile digital keys, was devised.

PUF can generate random numbers by utilizing unpredictable and uncontrollable process deviations in hardware equipment. By using such random numbers for key generation and authentication, a simple hardware chip that cannot be duplicated can compensate for the shortcomings of the existing software security method. can provide a way to do it.

More specifically, the output output when a specific input signal called challenge data is put into the PUF chip, which is formed differently depending on the process deviation, is called response data, and the PUF secures this challenge-response data pair (CRP). It can be used in the authentication process. In this case, some or all of the CRPs that can be generated in the PUF chip may be referred to as a CRPs table.

At this time, since the PUF has one CRPs table per one PUF chip, there is a limit to the security performance that only the number of CRPs in a single CRPs table can be used as an authentication key. This may increase the risk of hacking.

The present invention provides an apparatus and method for improving the security performance limit of a limited number of CRPs by performing authentication using an authentication device composed of a plurality of PUF chips.

The present invention provides an apparatus and method for enhancing security performance by generating PUF authentication information according to an authentication information generation rule shared with a server with respect to response data for at least one PUF chip.

An authentication apparatus according to an embodiment of the present invention includes a plurality of PUF (Physical Unclonable Function) chips that output different response data to the same challenge data, and the authentication apparatus is shared with a server selects at least one PUF chip from among the plurality of PUF chips according to an authentication information generation rule, generates PUF authentication information using response data when challenge data is input to the selected PUF chip, and the PUF authentication The information may be used to derive an authentication result through comparison with server authentication information generated by the server according to the same authentication information generation rule as the authentication information generation rule used to generate the PUF authentication information.

When two or more PUF chips are selected from among the plurality of PUF chips according to the authentication information generation rule, the authentication device receives the challenge data from each other according to the output order of response data output when the challenge data is inputted to the selected PUF chips Other PUF authentication information may be generated.

An authentication apparatus according to an embodiment of the present invention includes a plurality of PUF (Physical Unclonable Function) chips that output different response data to the same challenge data, and the authentication apparatus is shared with a server At least one PUF chip is selected from among the plurality of PUF chips according to an authentication information generation rule, and PUF authentication information is generated using response data and random noise data when challenge data is input to the selected PUF chip. The PUF authentication information may be used to derive an authentication result through comparison with server authentication information generated by a server according to the same authentication information generation rule as the authentication information generation rule used to generate the PUF authentication information.

In the PUF authentication information, different PUF authentication information may be generated according to a type and number of the noise data and an output order of the response data and the noise data.

An authentication apparatus according to an embodiment of the present invention includes a plurality of PUF (Physical Unclonable Function) chips that output different response data to the same challenge data, and the authentication apparatus is shared with a server Selecting at least two PUF chips from among the plurality of PUF chips according to the authentication information generation rule, and generating PUF authentication information using the operation results of response data when challenge data is input to the selected PUF chips, , the PUF authentication information may be used to derive an authentication result through comparison with server authentication information generated by a server according to the same authentication information generation rule as the authentication information generation rule used to generate the PUF authentication information.

In the PUF authentication information, different PUF authentication information may be generated according to the number of the selected PUF chips, a type of operation between the selected PUF chips, and an operation order.

The authentication device generates PUF authentication information by adding arbitrary noise data to the operation result of the response data, and the PUF authentication information includes a type and number of the noise data, an operation result of the response data, and an output of the noise data. Different PUF authentication information may be generated according to the order.

An authentication device according to an embodiment of the present invention includes a plurality of PUF (Physical Unclonable Function) chips that output different response data to the same challenge data, and the authentication device includes a challenge- Receives the challenge-response data pair for non-authentication among the response data pairs (CRPs table), selects at least one PUF chip among the plurality of PUF chips, and according to the authentication information generation rule shared with the server, the selected PUF chip PUF authentication information is generated using response data when challenge data received together with the challenge-response data pair for non-authentication is input, and the PUF authentication information is an authentication information generation rule used to generate the PUF authentication information It can be used to derive an authentication result through comparison with the server authentication information generated by the server according to the same authentication information generation rule as .

The authentication apparatus may select a PUF chip that outputs the same challenge-response data as the received challenge-response data pair for non-authentication from among the plurality of PUF chips.

When two or more PUF chips are selected from among the plurality of PUF chips according to the challenge-response data pair for non-authentication, the authentication device outputs response data output when the challenge data is input to the selected PUF chips Different PUF authentication information may be generated according to the order.

The authentication device generates PUF authentication information by adding arbitrary noise data to the response data, and the PUF authentication information is different according to the type and number of the noise data and the output order of the response data and the noise data. Authentication information may be generated.

When two or more PUF chips are selected from among the plurality of PUF chips according to the challenge-response data pair for non-authentication, the authentication device calculates response data output when the challenge data is input to the selected PUF chips The PUF authentication information is generated using the result, and the PUF authentication information is generated according to the number and type of random noise data added to the operation result of the response data, the operation result of the response data, and the output order of the noise data. Different PUF authentication information may be generated.

The authentication device may share a rule list with the server, and may sequentially select and update different authentication information generation rules included in the rule list every predetermined period from a reference time.

The authentication device may select and update a predetermined authentication information generation rule for the corresponding time information based on the time information at which the authentication procedure is performed.

The authentication device shares a valid challenge list and a rule list with the server, and when the challenge information is not included in the valid challenge list, sequentially selects different authentication information generation rules included in the rule list can be updated.

The present invention can improve the security performance limit of the limited number of CRPs by performing authentication using an authentication device composed of a plurality of PUF chips.

The present invention can enhance security performance by generating PUF authentication information according to the authentication information generation rule shared with the server for response data to at least one PUF chip.

1 is a diagram illustrating an authentication system according to an embodiment of the present invention.
2 is a diagram illustrating a first example of an authentication method performed by an authentication system according to an embodiment of the present invention.
3 is a diagram illustrating a second example of an authentication method performed by an authentication system according to an embodiment of the present invention.
4 is a diagram illustrating a third example of an authentication method performed by an authentication system according to an embodiment of the present invention.
5 is a diagram illustrating a fourth example of an authentication method performed by an authentication system according to an embodiment of the present invention.
6 is a diagram illustrating a fifth example of an authentication method performed by an authentication system according to an embodiment of the present invention.
7 is a diagram illustrating a sixth example of an authentication method performed by an authentication system according to an embodiment of the present invention.

Hereinafter, embodiments of the present invention will be described in detail with reference to the accompanying drawings.

1 is a diagram illustrating an authentication system according to an embodiment of the present invention.

The authentication system 100 of the present invention may include a server 110 and an authentication device 120 . The authentication device 120 may include multiple PUF circuits including one or more PUF chips. For example, the authentication device 120 may include a plurality of PUF chips 121 to 124 as shown in FIG. 1 , and each of the plurality of PUF chips 121 to 124 has different unique responses to the same challenge data. data can be output.

The challenge-response data pairs for each of the plurality of PUF chips 121 to 124 may be referred to as a CRPs table, and the server 110 has a CRPs table for each of the plurality of PUF chips 121 to 124. can be saved At this time, the CRPs table stored in the server 110 may be composed of some or all of the CRPs that can be generated by the individual PUF chips 121 to 124 .

The authentication system 100 of the present invention improves the security performance limit of the limited number of CRPs in the authentication system through a single PUF chip by using the authentication device 120 composed of a plurality of PUF chips 121 to 124 as described above. can do. In addition, the authentication system 100 of the present invention outputs various responses to the same challenge data, so even if some CRPs are leaked, it may not be possible to utilize them or may be an authentication system with low probability of utilization. That is, in the authentication system 100 of the present invention, even if the authentication device 120 responds to the challenge data requested by an attacker other than the server 110 , the attacker utilizes the response in the authentication procedure with the server 110 . Security can be improved by preventing it or dramatically reducing the usability.

On the other hand, a process in which the authentication device 120 puts challenge data into an internal individual PUF chip and obtains response data is called a random number reading mode, and a PUF to be returned to the server 110 based on the response data generated from the individual PUF chip. It may be referred to as an authentication information generation mode in which authentication information is generated. In this case, the authentication device 120 may select one or two or more PUF chips to be used to generate the PUF authentication information, and perform a PUF combination or operation according to the authentication information generation rule based on the response data of the selected PUF chip. You can create authentication information.

At this time, the authentication information generation rule for generating the PUF authentication information is shared by the server 110 and the authentication device 120, and the server 110 generates the server authentication information and the authentication device through the authentication information generation rule. By comparing and analyzing the PUF authentication information received in 120 , it is possible to determine whether the authentication device 120 is authenticated.

Since the authentication device 120 can generate various response data for the same challenge data, even if the response data is leaked, if the authentication information generation rule is updated, the leaked response data cannot be recycled in the authentication procedure or the recyclability is low, so security sex can be strengthened.

In addition, when the operation result between the response data generated by the plurality of PUF chips is used as the PUF authentication information, since this is an operation result using a plurality of random numbers, even if the PUF authentication information is known, the response data of the PUF chips used for the operation cannot be extracted That is, even if an attacker other than the server 110 has information on the authentication information generation rule, since the CRPs table cannot be directly hacked, the security of authentication can be strengthened.

Meanwhile, the authentication information generation rule shared by the server 110 and the authentication device 120 may be updated according to a predetermined method.

(1) Fixed periodic type.

The server 110 and the authentication device 120 may share a reference time and a list of rules in advance. Thereafter, the server 110 and the authentication device 120 may sequentially select and update a plurality of authentication information generation rules included in the rule list every predetermined period from the reference time through their respective clocks.

(2) Time information type.

The server 110 and the authentication device 120 may share information on which rule to use in advance according to the rule list and time information. After that, based on the real-time information on which the authentication process is performed, it is possible to select and update an authentication information generation rule suitable for the corresponding time information. At this time, the time information is the time when the server 110 transmits the challenge data to the authentication device 120 or the time when the authentication device 120 receives the challenge data or the authentication device 120 sends the PUF authentication information to the server ( 110) may mean real-time information during the authentication process, such as the time transmitted.

(3) Effective challenge data confirmation type.

Theoretically, the number of available challenge data is the number of bits of challenge data, 2 to the N power of N. When the length of the CRPs table that the server 110 has is N or less, the number of valid challenge data may be a part of 2 to N power branches. The authentication device 120 shares the valid challenge data list and the rule list with the server 110 in advance, and when PUF authentication information for challenge data other than the valid challenge data is requested, a plurality of included in the rule list The authentication information generation rules can be sequentially selected and updated. On the other hand, when the PUF authentication information received from the authentication device is different from the server authentication information, the server 110 may update the authentication information generation rule.

2 is a diagram illustrating a first example of an authentication method performed by an authentication system according to an embodiment of the present invention.

Referring to FIG. 2 , the authentication apparatus 120 of the present invention may generate PUF authentication information using one PUF chip or one unit of response data according to an authentication information generation rule. Specifically, the authentication device 120 selects at least one PUF chip from among a plurality of PUF chips according to the authentication information generation rule shared with the server, and uses response data when challenge data is inputted to the selected PUF chip. You can create authentication information.

As an example, Table 1 below shows an update order of an authentication information generation rule and definitions of detailed rules. The definition of such an update order and detailed rules is not limited to Table 1 below, and various methods may be defined.

<Table 1>

First, at time (1), the server 110 may transmit the challenge data (C) "1" to the user terminal including the authentication device 120 composed of a plurality of PUF chips. Then, at time (2), the authentication device 120 selects PUF1 from among the plurality of PUF chips according to the authentication information generation rule 1, and the response data (R) when the challenge data “1” is input to PUF1. A" may be returned to the server 110 as PUF authentication information. At time (3), the server 110 generates "A" as the server authentication information, which is response data when the challenge data "1" is input to PUF1 according to the authentication information generation rule 1 in the same manner as the authentication device 120 . and by comparing it with PUF authentication information, it is possible to derive an authentication result indicating that authentication has been successful. Thereafter, the server 110 may terminate the authentication by transmitting the authentication result for the authentication success to the authentication device 120 .

If, as in time (4), the hacker transmits arbitrary challenge data to the authentication device 120 of the user terminal pretending to be the server 110, the authentication device 120 performs at time (5) and The PUF authentication information generated as response data corresponding to arbitrary challenge data is returned according to the authentication information generation rule shared with the server 110 and the method of updating it, and the hacker authenticates the PUF from the authentication device 120 . information can be collected. If this is repeated from time (6) to time (k+1), the hacker CRPs table can be collected as shown in FIG. 2 .

If, as in time (k+2), the server 110 transmits the challenge data “8” to the hacker pretending to be a user terminal, as in time (k+3), the hacker authenticates the previous user terminal In the hacker CRPs table collected through the device 120, response data "d" to the challenge data "8" may be returned as PUF authentication information. In this case, the response data "d" used by the hacker for authentication is response data collected according to the authentication information generation rule 4. That is, since the authentication information generation rule 1 is applied at time (k+4), the server 110 can generate "D", which is response data when the challenge data "8" is inputted to PUF1, as server authentication information, , since this is different from the PUF authentication information "d" received from the hacker, authentication may fail.

3 is a diagram illustrating a second example of an authentication method performed by an authentication system according to an embodiment of the present invention.

Referring to FIG. 3 , the authentication device 120 of the present invention may generate PUF authentication information using one PUF chip or one unit of response data according to an authentication information generation rule. Specifically, the authentication device 120 selects at least one PUF chip from among a plurality of PUF chips according to the authentication information generation rule shared with the server, and receives response data and random noise when challenge data is input to the selected PUF chip. (Noise) data may be used to generate PUF authentication information. In this case, the random noise data may be PUF response data according to the random challenge data or a random number generated through a separate random number generator. Alternatively, random noise data may be generated in various ways through a separate memory storing garbage data.

As an example, Table 2 below shows an update order of an authentication information generation rule and definitions of detailed rules. The definition of such an update order and detailed rules is not limited to Table 2 below, and various methods may be defined.

<Table 2>

First, at time (1), the server 110 may transmit the challenge data (C) "1" to the user terminal including the authentication device 120 composed of a plurality of PUF chips. Then, at time (2), the authentication device 120 selects PUF1 from among the plurality of PUF chips according to the authentication information generation rule 1, and the response data (R) when the challenge data “1” is input to PUF1. PUF authentication information in which A" and noise data N are output in order may be returned to the server 110 . At time (3), the server 110, in the same manner as the authentication device 120, receives “A”, which is response data when the challenge data “1” is input to PUF1, according to the authentication information generation rule 1, and the noise data in order By outputting it, it is generated as server authentication information, and by comparing it with PUF authentication information, it is possible to derive an authentication result indicating that authentication is successful. Thereafter, the server 110 may terminate the authentication by transmitting the authentication result for the authentication success to the authentication device 120 .

If, as in time (4), the hacker transmits arbitrary challenge data to the authentication device 120 of the user terminal pretending to be the server 110, the authentication device 120 performs at time (5) and The PUF authentication information generated as response data and noise data corresponding to random challenge data is returned according to the authentication information generation rule shared with the server 110 and the method of updating it, and the hacker receives the authentication information from the authentication device 120 . You can collect the corresponding PUF authentication information. If this is repeated from time (6) to time (k+1), the hacker CRPs table can be collected as shown in FIG. 3 .

If, as in time (k+2), the server 110 transmits the challenge data “8” to the hacker pretending to be a user terminal, as in time (k+3), the hacker authenticates the previous user terminal In the hacker CRPs table collected through the device 120, response data "N+R" to the challenge data "8" may be returned as PUF authentication information. At this time, the response data "N+R" used by the hacker for authentication is response data collected according to the authentication information generation rule M. That is, at time (k+4), since authentication information generation rule 1 is applied, the server 110 sequentially receives "D" and noise data "N", which are response data when challenge data "8" is input to PUF1. It can be output and generated as server authentication information (D+N), which is different from PUF authentication information "N+R" received from a hacker, so authentication may fail.

In this case, in the above example, PUF authentication information indicates a result of combining one response data and one noise data. However, in the PUF authentication information, different PUF authentication information may be generated according to (i) the type of noise data, (ii) the number, and (iii) the output order of the response data and the noise data.

More specifically, the noise data may be a combination of consecutive bits. Accordingly, different types of noise data may be output according to the number of consecutive bits or a difference in bit values for the corresponding number of bits.

Accordingly, the authentication apparatus 120 may select at least one or more noise data among these different types of noise data, and may generate more various PUF authentication information by changing the order in which the selected noise data and response data are output. can That is, the authentication device 120 can enhance the security of authentication by generating more various types of PUF authentication information according to (i) the type of noise data, (ii) the number, and (iii) the output order of response data and noise data. can

4 is a diagram illustrating a third example of an authentication method performed by an authentication system according to an embodiment of the present invention.

Referring to FIG. 4 , the authentication apparatus 120 of the present invention may generate PUF authentication information by combining response data for a plurality of PUF chips according to an authentication information generation rule. Specifically, the authentication device 120 selects at least two PUF chips from among the plurality of PUF chips according to the authentication information generation rule shared with the server, and uses response data when challenge data is input to the selected PUF chips. PUF authentication information may be generated.

As an example, Table 3 below shows an update order of an authentication information generation rule and definitions of detailed rules. The definition of such an update order and detailed rules is not limited to Table 3 below, and various methods may be defined.

<Table 3>

First, at time (1), the server 110 may transmit the challenge data (C) "1" to the user terminal including the authentication device 120 composed of a plurality of PUF chips. Then, at time (2), the authentication device 120 selects PUF1 and PUF2 from among the plurality of PUF chips according to the authentication information generation rule 1, and the response data when the challenge data "1" is inputted to PUF1 and PUF2 ( R), "A" and "a" may return the PUF authentication information output in order to the server 110 . At time (3), the server 110 responds to the response data “A” and “a” when the challenge data “1” is inputted to PUF1 and PUF2 according to the authentication information generation rule 1 in the same manner as the authentication device 120 . By sequentially outputting server authentication information, it is possible to derive an authentication result indicating that authentication is successful by generating server authentication information and comparing it with PUF authentication information. Thereafter, the server 110 may terminate the authentication by transmitting the authentication result for the authentication success to the authentication device 120 .

If, as in time (4), the hacker transmits arbitrary challenge data to the authentication device 120 of the user terminal pretending to be the server 110, the authentication device 120 performs at time (5) and The PUF authentication information generated as response data corresponding to arbitrary challenge data is returned according to the authentication information generation rule shared with the server 110 and the method of updating the same, and the hacker returns the PUF authentication information from the authentication device 120 You can collect authentication information. If this is repeated from time (6) to time (k+1), the hacker CRPs table can be collected as shown in FIG. 4 .

If, as in time (k+2), the server 110 transmits the challenge data “8” to the hacker pretending to be a user terminal, as in time (k+3), the hacker authenticates the previous user terminal In the hacker CRPs table collected through the device 120 , it is possible to reply “d+la”, which is response data to the challenge data “8”, as PUF authentication information. At this time, the response data "d+" used by the hacker for authentication is response data collected according to the authentication information generation rule M. That is, at time (k+4), since the authentication information generation rule 1 is applied, the server 110 sequentially returns "D" and "d", which are response data when the challenge data "8" is input to PUF1 and PUF2. By outputting it, it is possible to generate server authentication information (D+d), which is different from the PUF authentication information "d+ra" received from a hacker, so authentication may fail.

5 is a diagram illustrating a fourth example of an authentication method performed by an authentication system according to an embodiment of the present invention.

Referring to FIG. 5 , the authentication apparatus 120 of the present invention may generate PUF authentication information using response data for a plurality of PUF chips according to an authentication information generation rule. Specifically, the authentication device 120 selects two or more PUF chips from among a plurality of PUF chips according to the authentication information generation rule shared with the server, and receives response data and random data when challenge data is input to the selected PUF chips. PUF authentication information may be generated using noise data. In this case, the random noise data may be PUF response data according to the random challenge data or a random number generated through a separate random number generator. Alternatively, random noise data may be generated in various ways through a separate memory storing garbage data.

As an example, Table 4 below shows the update order of authentication information generation rules and definitions of detailed rules. The definition of such an update order and detailed rules is not limited to Table 4 below, and various methods may be defined.

<Table 4>

First, at time (1), the server 110 may transmit the challenge data (C) "1" to the user terminal including the authentication device 120 composed of a plurality of PUF chips. Then, at time (2), the authentication device 120 selects PUF1 and PUF2 from among the plurality of PUF chips according to the authentication information generation rule 1, and the response data when the challenge data "1" is inputted to PUF1 and PUF2 ( R), "A" and "a" may return the PUF authentication information output in order to the server 110 . At time (3), the server 110 responds to the response data “A” and “a” when the challenge data “1” is inputted to PUF1 and PUF2 according to the authentication information generation rule 1 in the same manner as the authentication device 120 . It is possible to derive an authentication result indicating that authentication is successful by outputting in order to generate the server authentication information and comparing it with the PUF authentication information. Thereafter, the server 110 may terminate the authentication by transmitting the authentication result for the authentication success to the authentication device 120 .

If, as in time (4), the hacker transmits arbitrary challenge data to the authentication device 120 of the user terminal pretending to be the server 110, the authentication device 120 performs at time (5) and The PUF authentication information generated as response data and noise data corresponding to random challenge data is returned according to the authentication information generation rule shared with the server 110 and the method of updating it, and the hacker receives the authentication information from the authentication device 120 . You can collect the corresponding PUF authentication information. If this is repeated from time (6) to time (k+1), the hacker CRPs table can be collected as shown in FIG. 5 .

If, as in time (k+2), the server 110 transmits the challenge data “8” to the hacker pretending to be a user terminal, as in time (k+3), the hacker authenticates the previous user terminal In the hacker CRPs table collected through the device 120, response data "N+R" to the challenge data "8" may be returned as PUF authentication information. At this time, the response data "N+R" used by the hacker for authentication is response data collected according to the authentication information generation rule M. That is, at time (k+4), since the authentication information generation rule 1 is applied, the server 110 sequentially returns "D" and "d", which are response data when the challenge data "8" is input to PUF1 and PUF2. It can be output to generate server authentication information (D+d), which is different from PUF authentication information "N+r" received from a hacker, so authentication may fail.

In this case, in the above example, PUF authentication information indicates a result of combining two response data or one response data and one noise data. However, PUF authentication information may generate different PUF authentication information according to (i) the number of response data, (ii) the type of noise data, (iii) the number, and (iv) the output order of the response data and the noise data. .

More specifically, the noise data may be a combination of consecutive bits. Accordingly, different types of noise data may be output according to the number of consecutive bits or a difference in bit values for the corresponding number of bits.

Accordingly, the authentication apparatus 120 may select at least one or more noise data among these different types of noise data, and may generate more various PUF authentication information by changing the order in which the selected noise data and response data are output. can That is, the authentication device 120 obtains more various types of PUF authentication information according to (i) the number of response data, (ii) the type of noise data, (iii) the number, and (iv) the output order of the response data and the noise data. By creating it, the security of authentication can be strengthened.

6 is a diagram illustrating a fifth example of an authentication method performed by an authentication system according to an embodiment of the present invention.

Referring to FIG. 6 , the authentication apparatus 120 of the present invention may generate PUF authentication information by using the operation result of response data for a plurality of PUF chips according to the authentication information generation rule. Specifically, the authentication device 120 selects at least two PUF chips from among the plurality of PUF chips according to the authentication information generation rule shared with the server, and provides various responses to response data when challenge data is input to the selected PUF chips. PUF authentication information can be generated by performing a type of operation.

As an example, Table 5 below shows the update order of authentication information generation rules and definitions of detailed rules. The definition of such an update order and detailed rules is not limited to Table 5 below, and various methods may be defined.

<Table 5>

First, at time (1), the server 110 may transmit the challenge data (C) "1" to the user terminal including the authentication device 120 composed of a plurality of PUF chips. Then, at time (2), the authentication device 120 selects PUF1 and PUF2 from among the plurality of PUF chips according to the authentication information generation rule 1, and the response data when the challenge data "1" is inputted to PUF1 and PUF2 ( The XOR operation result for "A" and "a", which is R), may be returned to the server 110 as PUF authentication information. At time (3), the server 110 responds to the response data “A” and “a” when the challenge data “1” is inputted to PUF1 and PUF2 according to the authentication information generation rule 1 in the same manner as the authentication device 120 . By generating the XOR operation result for the server authentication information and comparing it with the PUF authentication information, it is possible to derive the authentication result indicating that the authentication was successful. Thereafter, the server 110 may terminate the authentication by transmitting the authentication result for the authentication success to the authentication device 120 .

If, as in time (4), the hacker transmits arbitrary challenge data to the authentication device 120 of the user terminal pretending to be the server 110, the authentication device 120 performs at time (5) and Similarly, according to the authentication information generation rule shared with the server 110 and a method of updating it, the calculation result of response data corresponding to arbitrary challenge data is returned as PUF authentication information, and the hacker returns the PUF authentication information from the authentication device 120 . You can collect authentication information. By repeating this from time (6) to time (k+1), a table of hacker CRPs can be collected.

ㄹ"를 PUF 인증 정보로써 회신할 수 있다. 이때, 해커가 인증에 사용한 응답 데이터 "라

ㄹ"는 인증 정보 생성 규칙 M에 따라 수집된 응답 데이터이다. 즉, 시간 (k+4)에서는 인증 정보 생성 규칙 1이 적용되므로 서버(110)는 PUF1과 PUF2에 첼린지 데이터 "8"을 입력하였을 때의 응답 데이터인 "D"와 "d"의 XOR 연산 결과를 서버 인증 정보(D

d)로 생성할 수 있으며, 이는 해커로부터 수신된 PUF 인증 정보 "라

ㄹ"와 다르므로 인증은 실패할 수 있다.If, as in time (k+2), the server 110 transmits the challenge data “8” to the hacker pretending to be a user terminal, as in time (k+3), the hacker authenticates the previous user terminal In the hacker CRPs table collected through the device 120, the response data to the challenge data “8”

d" can be returned as PUF authentication information. At this time, the response data used by the hacker for authentication is

d" is the response data collected according to the authentication information generation rule M. That is, since the authentication information generation rule 1 is applied at time (k+4), the server 110 inputs the challenge data "8" to PUF1 and PUF2. The XOR operation result of "D" and "d", which is the response data when

d), which is the PUF authentication information received from a hacker.

d", so authentication may fail.

In this case, in the above example, the PUF authentication information indicates an XOR operation result for two response data. However, in the PUF authentication information, different PUF authentication information may be generated according to (i) the number of selected PUF chips, (ii) an operation type between the selected PUF chips, and (iii) an operation order.

More specifically, the PUF authentication information may be generated through a logical operation result on at least two pieces of response data, and for the logical operation, at least one of AND, OR, NOT, NAND, NOR, XOR, and XNOR may be selected.

Accordingly, the authentication apparatus 120 may select at least one or more logical operations from among these different types of logical operations, and may generate more various PUF authentication information by changing the operation order of response data to the selected logical operations. there is. That is, the authentication device 120 may enhance the security of authentication by generating different PUF authentication information according to (i) the number of selected PUF chips, (ii) an operation type between the selected PUF chips, and (iii) an operation order. .

7 is a diagram illustrating a sixth example of an authentication method performed by an authentication system according to an embodiment of the present invention.

Referring to FIG. 7 , the server 110 of the present invention owns the CRPs table of individual PUF chips constituting the authentication device 120 , but the CRPs table corresponds to the challenge-response data pair for authentication as shown in Table 6 below. It can be divided into Part 1 and Part 2 corresponding to the challenge-response data pair for non-authentication used for selection of the PUF chip.

<Table 6>

Specifically, when the server 110 transmits any challenge data in Part 1 to the authentication device 120 , the server 110 may transmit any challenge-response data pair (CRP) of Part 2 together. The authentication device 120 of the user terminal may select a PUF chip that matches the response data of the CRP transmitted in Part 2 by applying the challenge data of the CRP transmitted in Part 2 to individual PUF chips. Thereafter, the authentication apparatus 120 may generate PUF authentication information by inputting the challenge data transmitted in Part 1 to at least one or more selected PUF chips and using the output response data.

As an example, Table 7 below shows an update order of authentication information generation rules and definitions of detailed rules. The definition of such an update order and detailed rules is not limited to Table 7 below, and various methods may be defined.

<Table 7>

First, at time (1), the server 110 is a user terminal including the authentication device 120 composed of a plurality of PUF chips, and the challenge data (C) “1” of Part 1 and the CRP data “7” of Part 2 -A" can be combined to transmit. Then, at time (2), the authentication device 120 selects PUF3 from among the plurality of PUF chips based on the CRP data “7-ah” of Part 2, and inputs the challenge data “1” of Part 1 to PUF3. It is possible to return "a", which is the response data R at the time of doing this, to the server 110 as PUF authentication information. At time (3), the server 110 selects PUF3 in the same way as the authentication device 120, and receives "a", which is response data when the challenge data "1" is input to PUF3 according to the authentication information generation rule 1 By outputting it, it is generated as server authentication information, and by comparing it with PUF authentication information, it is possible to derive an authentication result indicating that authentication is successful. Thereafter, the server 110 may terminate the authentication by transmitting the authentication result for the authentication success to the authentication device 120 .

If, as in time (4), the hacker pretends to be the server 110 and transmits random challenge data “$$$” to the authentication device 120 of the user terminal ($$$: the hacker randomly sends If the value does not match the format or the CRP data of Part 2 is a random value that does not match the CRP of any PUF chip, the authentication device 120 determines that “$$$” is invalid challenge data. It can be judged as an attack from the outside. Then, the authentication device 120 returns any noise data as in time (5), and the hacker can collect the noise data from the authentication device 120 .

However, as in time (6), when the hacker transmits valid challenge data "4+(3-F)" to the authentication device 120, the authentication device 120 transmits authentication information as in time (7). PUF authentication information may be returned according to the generation rule. In this case, the authentication device 120 may update the authentication information generation rule when invalid challenge data is received more than a predetermined number of times. For example, when random challenge data “$$$” is received at time (k), the authentication device 120 may confirm that the existing authentication information generation rule 1 is changed to the authentication information generation rule 2. In this case, it can be identified that the rule has been updated through separate communication between the server 110 and the authentication device 120 . Repeating up to time (k+1), the hacker can collect the hacker CRPs table.

If, as at time (k+2), the server 110 transmits the challenge data "4+(3-F)" to a hacker pretending to be a user terminal, as at time (k+3), the hacker may return "B", which is response data to the challenge data "8", as PUF authentication information in the hacker CRPs table collected through the authentication device 120 of the previous user terminal. At this time, the response data "B" used by the hacker for authentication is response data collected according to the authentication information generation rule 1.

That is, since the authentication information generation rule 2 is applied at time (k+4), the server 110 uses “b”, which is response data when the challenge data “4+(3-F)” is input, as the server authentication information. can be generated, which is different from the PUF authentication information "B" received from the hacker, so authentication may fail.

Meanwhile, when the server 110 transmits the challenge data of Part 1 and the challenge-response data pair (CRP) of Part 2 to the authentication device 120 , additional noise data may be added and transmitted. In addition, the challenge-response data pair (CRP) of Part 2 may be used as data for directly or indirectly selecting at least one PUF chip among a plurality of PUF chips, and may be used in various ways, such as internal operation.

Meanwhile, the method according to the present invention is written as a program that can be executed on a computer and can be implemented in various recording media such as magnetic storage media, optical reading media, and digital storage media.

Implementations of the various techniques described herein may be implemented in digital electronic circuitry, or in computer hardware, firmware, software, or combinations thereof. Implementations may be implemented for processing by, or for controlling the operation of, a data processing device, eg, a programmable processor, computer, or number of computers, a computer program product, ie an information carrier, eg, a machine readable storage It may be embodied as a computer program tangibly embodied in an apparatus (computer readable medium) or a radio signal. A computer program, such as the computer program(s) described above, may be written in any form of programming language, including compiled or interpreted languages, as a standalone program or in a module, component, subroutine, or computing environment. It can be deployed in any form, including as other units suitable for use in A computer program may be deployed to be processed on one computer or multiple computers at one site or distributed across multiple sites and interconnected by a communications network.

Processors suitable for processing a computer program include, by way of example, both general and special purpose microprocessors, and any one or more processors of any kind of digital computer. Generally, a processor will receive instructions and data from either read-only memory or random access memory or both. Elements of a computer may include at least one processor that executes instructions and one or more memory devices that store instructions and data. In general, a computer may include one or more mass storage devices for storing data, for example magnetic, magneto-optical disks, or optical disks, receiving data from, sending data to, or both. may be combined to become Information carriers suitable for embodying computer program instructions and data are, for example, semiconductor memory devices, for example, magnetic media such as hard disks, floppy disks and magnetic tapes, Compact Disk Read Only Memory (CD-ROM). ), optical recording media such as DVD (Digital Video Disk), magneto-optical media such as optical disk, ROM (Read Only Memory), RAM (RAM) , Random Access Memory), flash memory, EPROM (Erasable Programmable ROM), EEPROM (Electrically Erasable Programmable ROM), and the like. Processors and memories may be supplemented by, or included in, special purpose logic circuitry.

In addition, the computer-readable medium may be any available medium that can be accessed by a computer, and may include both computer storage media and transmission media.

While this specification contains numerous specific implementation details, they should not be construed as limitations on the scope of any invention or claim, but rather as descriptions of features that may be specific to particular embodiments of particular inventions. should be understood Certain features that are described herein in the context of separate embodiments may be implemented in combination in a single embodiment. Conversely, various features that are described in the context of a single embodiment may also be implemented in multiple embodiments, either individually or in any suitable subcombination. Furthermore, although features operate in a particular combination and may be initially depicted as claimed as such, one or more features from a claimed combination may in some cases be excluded from the combination, the claimed combination being a sub-combination. or a variant of a sub-combination.

Likewise, although acts are depicted in the figures in a particular order, it should not be construed that all acts shown must be performed or that such acts must be performed in the specific order or sequential order shown in order to achieve desirable results. In certain cases, multitasking and parallel processing may be advantageous. Further, the separation of the various device components of the above-described embodiments should not be construed as requiring such separation in all embodiments, and the program components and devices described may generally be integrated together into a single software product or packaged into multiple software products. You have to understand that you can.

On the other hand, the embodiments of the present invention disclosed in the present specification and drawings are merely presented as specific examples to aid understanding, and are not intended to limit the scope of the present invention. It is apparent to those of ordinary skill in the art to which the present invention pertains that other modifications based on the technical spirit of the present invention can be implemented in addition to the embodiments disclosed herein.

100: authentication system
110 : server
120: authentication device
121~124: PUF chip

Claims (15)

In the authentication device,
It includes a plurality of PUF (Physical Unclonable Function) chips that output different response data to the same challenge data,
The authentication device is
Selecting at least one PUF chip from among the plurality of PUF chips according to an authentication information generation rule shared with the server, and generating PUF authentication information using response data when challenge data is input to the selected PUF chip,
The PUF authentication information is
An authentication device used to derive an authentication result through comparison with server authentication information generated by a server according to the same authentication information generation rule as the authentication information generation rule used to generate the PUF authentication information. According to claim 1,
The authentication device is
When two or more PUF chips are selected from among the plurality of PUF chips according to the authentication information generation rule, different PUF authentication information according to an output order of response data output when the challenge data is input to the selected PUF chips An authentication device that generates In the authentication device,
It includes a plurality of PUF (Physical Unclonable Function) chips that output different response data to the same challenge data,
The authentication device is
PUF authentication using response data and random noise data when at least one PUF chip is selected from among the plurality of PUF chips according to the authentication information generation rule shared with the server, and challenge data is input to the selected PUF chip create information,
The PUF authentication information is
An authentication device used to derive an authentication result through comparison with server authentication information generated by a server according to the same authentication information generation rule as the authentication information generation rule used to generate the PUF authentication information. 4. The method of claim 3,
The PUF authentication information is
An authentication apparatus for generating different PUF authentication information according to a type and number of the noise data and an output order of the response data and the noise data. In the authentication device,
It includes a plurality of PUF (Physical Unclonable Function) chips that output different response data to the same challenge data,
The authentication device is
At least two PUF chips are selected from among the plurality of PUF chips according to an authentication information generation rule shared with the server, and PUF authentication information is obtained using the calculation results of response data when challenge data is input to the selected PUF chips. creates,
The PUF authentication information is
An authentication device used to derive an authentication result through comparison with server authentication information generated by a server according to the same authentication information generation rule as the authentication information generation rule used to generate the PUF authentication information. 6. The method of claim 5,
The PUF authentication information is
An authentication apparatus for generating different PUF authentication information according to the number of the selected PUF chips, a type of operation between the selected PUF chips, and an operation order. 6. The method of claim 5
The authentication device is
generating PUF authentication information by adding arbitrary noise data to the operation result of the response data;
The PUF authentication information is
An authentication apparatus for generating different PUF authentication information according to a type and number of the noise data, an operation result of the response data, and an output order of the noise data. In the authentication device,
It includes a plurality of PUF (Physical Unclonable Function) chips that output different response data to the same challenge data,
The authentication device is
receiving a challenge-response data pair for non-authentication from among the challenge-response data pairs (CRPs table) and selecting at least one PUF chip from among the plurality of PUF chips;
According to the authentication information generation rule shared with the server, PUF authentication information is generated using response data when the challenge data received together with the challenge-response data pair for non-authentication is input to the selected PUF chip,
The PUF authentication information is
An authentication device used to derive an authentication result through comparison with server authentication information generated by the server according to an authentication information generation rule identical to an authentication information generation rule used to generate the PUF authentication information. 9. The method of claim 8,
The authentication device is
An authentication apparatus for selecting a PUF chip that outputs the same challenge-response data as the received challenge-response data pair for non-authentication from among the plurality of PUF chips. 9. The method of claim 8,
The authentication device is
When two or more PUF chips are selected from among the plurality of PUF chips according to the challenge-response data pair for non-authentication, response data output when the challenge data is input to the selected PUF chips are outputted to each other An authentication device that generates different PUF authentication information. 9. The method of claim 8
The authentication device is
adding random noise data to the response data to generate PUF authentication information;
The PUF authentication information is
An authentication apparatus for generating different PUF authentication information according to a type and number of the noise data and an output order of the response data and the noise data. 9. The method of claim 8,
The authentication device is
When two or more PUF chips are selected from among the plurality of PUF chips according to the challenge-response data pair for non-authentication, the operation result of response data output when the challenge data is input to the selected PUF chips is used. generate the PUF authentication information;
The PUF authentication information is
The authentication apparatus for generating different PUF authentication information according to the number and type of random noise data added to the operation result of the response data, the operation result of the response data, and an output order of the noise data. 9. The method of claim 8,
The authentication device is
An authentication device that shares a rule list with the server and sequentially selects and updates different authentication information generation rules included in the rule list every predetermined period from a reference time. 9. The method of claim 8,
The authentication device is
An authentication device that selects and updates a predetermined authentication information generation rule for the corresponding time information based on the time information at which the authentication procedure is performed. 9. The method of claim 8,
The authentication device is
An authentication device that shares a valid challenge list and a rule list with the server, and sequentially selects and updates different authentication information generation rules included in the rule list when the challenge information is not included in the valid challenge list .

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