KR20190059003A - Key distribution processing apparatus for processing the distribution of a session key in an encrypted manner for the electronic control units mounted in a vehicle and operating method thereof - Google Patents

Abstract

Disclosed are a key distribution processing apparatus for processing a distribution of a session key in an encrypted manner for electronic control units (ECUs) mounted in a vehicle and an operation method thereof. The present invention relates to the key distribution processing apparatus which distributes the session key for supporting the ECUs mounted in the vehicle to perform encrypted communication in an encryption method based on Lagrange interpolation method, thereby minimizing a chance of key exposure.

Description

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a key distribution processing apparatus for processing distribution of a session key in an encrypted manner for ECUs mounted in a vehicle and a method of operating the same. MOUNTED IN A VEHICLE AND OPERATING METHOD THEREOF}

The present invention relates to a key distribution processing device for processing distribution of a session key to ECUs (Electronic Control Units) mounted in a vehicle and an operation method thereof.

Recently, as various types of information are generated and circulated, important information is exposed to a third party due to hacking or transmission of information to a wrong path.

Particularly, in case that important information such as military information or personal information is not applied in the process of transmitting information, and if such important information is accidentally transmitted to a third party, a third party can easily access important information , Can cause great damage.

Recently, in order to prevent exposure of such important information, a technique of encrypting important information by using a predetermined encryption key and transmitting it to the other party has been introduced.

In a general data encryption scheme, when the data transmission side and the data reception side share the same secret key and the data transmission side encrypts and transmits the data with the secret key, a method in which the data reception side decrypts the data with the same secret key is used .

In addition, recently, a communication module is mounted on a vehicle, and research on a connected car capable of transmitting and receiving data with other vehicles or external traffic facilities through a network is continuing.

Since vehicles equipped with such a network function receive various data from outside, if data for disturbing the control system of the vehicle is transmitted artificially from the outside, a problem occurs in the control of the vehicle, which is a great threat to the driver have.

For example, by manipulating various sensors mounted on the vehicle from the outside or attacking the ECUs (Electronic Control Units) of the vehicle, the driver controls the vehicle in an undesired form, thereby causing a large traffic accident Can cause problems.

Therefore, it is necessary to study a security technique for preventing data from being exposed due to an external intrusion when ECUs which are mounted inside the vehicle and control various components existing in the vehicle exchange data with each other .

In the present invention, a session key for supporting the ECU (Electronic Control Units) mounted in a vehicle to perform encrypted communication in data communication is distributed to each ECU by an encryption method based on a Lagrange interpolation method, And to provide a key distribution processing apparatus and a method of operating the same that can minimize the possibility of key exposure that may occur during exchange.

A key distribution processing device for processing the distribution of a session key in an encrypted manner for ECUs (Electronic Control Units) mounted in a vehicle according to an embodiment of the present invention is a key distribution processing device for distributing a session key in an encrypted manner to n ), A key transmission request unit for requesting transmission of the master key data to the n ECUs when a distribution command of the session key to the n ECUs is received as the network is connected to the n ECUs, A master key data receiver for receiving the n master key data when n master key data are transmitted from the n ECUs as each master key data is generated, Dimensional coordinate generating unit for generating n two-dimensional coordinate values by applying the two-dimensional coordinate generating functions as input to the selected two-dimensional coordinate generating function, A basic two-dimensional coordinate value generator for randomly generating a formal session key K and generating a basic two-dimensional coordinate value corresponding to '(0, K)' based on the session key K, A polynomial generating unit for generating an n-th order polynomial using Lagrange interpolation based on the n 2-dimensional coordinate values, a polynomial generating unit for generating n-th polynomials by using Lagrange interpolation based on the n 2-dimensional coordinate values, Dimensional coordinate values that do not coincide with the n two-dimensional coordinate values by applying the values of the n two-dimensional coordinate values for each of the n ECUs, and for transmitting the n different two-dimensional coordinate values for each of the n ECUs Thereby completing the distribution of the session key K.

Further, an operation method of a key distribution processing apparatus for processing distribution of a session key in an encrypted manner to ECUs mounted in a vehicle according to an embodiment of the present invention is a method of operating a key distribution processing apparatus, ) Requesting transmission of master key data to the n ECUs when a distribution command of a session key for the n ECUs is received as the network is connected to the n ECUs, Receiving n master key data when n different master key data are transmitted from the n ECUs by generating different master key data, receiving each of the n master key data, Generating n two-dimensional coordinate values by inputting to the coordinate generation function as input, randomly generating a session key K to be distributed to the n ECUs, Generating a basic two-dimensional coordinate value corresponding to '(0, K)' based on the partial key K, using the Lagrangian interpolation method based on the basic two-dimensional coordinate value and the n two- Generating a polynomial by applying n different input values that are not included in the n two-dimensional coordinate values to the n-th polynomial, generating n different two-dimensional coordinate values that do not match the n two- , And completing the distribution of the session key K by transmitting all of the n different two-dimensional coordinate values for each of the n ECUs.

In the present invention, a session key for supporting the ECU (Electronic Control Units) mounted in a vehicle to perform encrypted communication in data communication is distributed to each ECU by an encryption method based on a Lagrange interpolation method, It is possible to provide a key distribution processing apparatus and an operation method thereof that can minimize the possibility of key exposure that may occur at the time of exchange.

1 is a diagram showing a structure of a key distribution processing apparatus for processing distribution of a session key in an encrypted manner for ECUs (Electronic Control Units) mounted in a vehicle according to an embodiment of the present invention.
2 is a flowchart showing an operation method of a key distribution processing apparatus for processing distribution of a session key in an encrypted manner for ECUs mounted in a vehicle according to an embodiment of the present invention.

Hereinafter, embodiments according to the present invention will be described in detail with reference to the accompanying drawings. It is to be understood that the description is not intended to limit the invention to the specific embodiments, but includes all modifications, equivalents, and alternatives falling within the spirit and scope of the invention. Like reference numerals in the drawings are used for similar elements and, unless otherwise defined, all terms used in the specification, including technical and scientific terms, are to be construed in a manner that is familiar to those skilled in the art. It has the same meaning as commonly understood by those who have it.

1 is a diagram showing a structure of a key distribution processing apparatus for processing distribution of a session key in an encrypted manner for ECUs (Electronic Control Units) mounted in a vehicle according to an embodiment of the present invention.

1, the key distribution processing apparatus 110 includes a key transmission request unit 111, a master key data receiving unit 112, a two-dimensional coordinate generating unit 113, a basic two-dimensional coordinate value generating unit 114, A polynomial expression generation unit 115, an additional coordinate generation unit 116, and a key distribution processing unit 117.

The key transmission request unit 111 is connected to the n ECUs 131, 132, 133, and 134 via the network with n (n is a natural number of 2 or more) ECUs 131, 132, 133, 134, the request for transmission of the master key data to the n ECUs 131, 132, 133, 134 is requested.

Here, the key distribution processing apparatus 110 according to the present invention is an apparatus that can be mounted inside the vehicle, and includes n ECUs (131, 132, 133, 134) Can be configured to be connected.

The session key is a key used in a communication session generated by the n ECUs 131, 132, 133, and 134 to send and receive data to each other. The session key includes n ECUs 131, 132, 133, and 134, the n ECUs 131, 132, 133, and 134 can encrypt and transmit data by using the corresponding session key.

When the transfer of the master key data is requested to the n ECUs 131, 132, 133 and 134, each of the n ECUs 131, 132, 133, and 134 responds to the transfer request of the master key data And stores the generated master key data in a memory built in each of the n ECUs 131, 132, 133, and 134, and then transmits the master key data to the key distribution processing apparatus 110. [

The master key data receiving unit 112 receives the master key data from the n ECUs 131, 132, 133 and 134 as n master ECUs 131, 132, 133, When the master key data is transmitted, the n master key data are received.

The two-dimensional coordinate generating unit 113 generates n two-dimensional coordinate values by applying each of the n master key data to the selected two-dimensional coordinate generating function as an input.

The basic two-dimensional coordinate value generation unit 114 randomly generates a session key K to be distributed to the n ECUs 131, 132, 133, and 134 and generates' (0, K) Dimensional coordinate values corresponding to the two-dimensional coordinate values.

The polynomial generating unit 115 generates an n-th degree polynomial based on the basic two-dimensional coordinate value and the n two-dimensional coordinate values using a Lagrange interpolation method.

Here, the Lagrangian interpolation means a technique for obtaining an n-th order polynomial over n + 1 coordinate values if n + 1 coordinate values are known, and n + 1 When it is assumed that coordinate values exist, the n-th degree polynomial f (x) according to the Lagrangian interpolation method can be generated by the following equation (2).

Here, the Lagrange polynomial L _i (x) can be calculated according to the following equation (3).

In this manner, the polynomial generation unit 115 generates n polynomial coordinate values generated by the two-dimensional coordinate generation unit 113 and polynomial polynomial polynomial by using '(0, K)' generated by the basic two-dimensional coordinate value generation unit 114 The n-th order polynomial can be generated using the Lagrangian interpolation method based on the basic two-dimensional coordinate values.

The additional coordinate generator 116 applies n different input values not included in the n two-dimensional coordinate values to the n-th polynomial, thereby generating n different two-dimensional coordinate values that do not coincide with the n two- Dimensional coordinate values.

In this regard, when the n-th order polynomial generated by the polynomial generating unit 115 is denoted by 'f (x)', the additional coordinate generating unit 116 generates the n 2 ' Axis coordinate values, and inputting another input value not included in the x-axis value of the dimensional coordinate values as the x-axis value in the n-th order polynomial f (x) Can be generated.

For example, when the n two-dimensional coordinate values are '(a, b), (c, d)', the additional coordinate generating unit 116 generates another coordinate value ' (e, g), (f, f) that do not match the n two-dimensional coordinate values' a, b, h) '. < / RTI >

When the n different two-dimensional coordinate values are generated, the key distribution processing unit 117 transmits all of the n different two-dimensional coordinate values to each of the n ECUs 131, 132, 133, and 134, Distribution of the key K is completed.

In this case, according to an embodiment of the present invention, each of the n ECUs 131, 132, 133, and 134 may store the selected two-dimensional coordinate generating function on the memory.

When the n different two-dimensional coordinate values are received from the key distribution processing unit 110, each of the n ECUs 131, 132, 133, and 134 outputs n ECUs 131, 132, 133, Dimensional coordinate generating function stored in the memory to generate a two-dimensional master coordinate value, and then generates the two-dimensional master coordinate value by using the n < th > The n-th order polynomial for key detection can be generated using Lagrange interpolation based on the two-dimensional master coordinate values generated by the n ECUs 131 and the two other two-dimensional coordinate values.

Each of the n ECUs 131, 132, 133, and 134 may then calculate the session key K and store it in the memory by applying '0' to the n-th polynomial for key detection as an input value .

For example, it is assumed that the master key data generated by ECU 1 131 among n ECUs 131, 132, 133, and 134 is 'master key data 1'. At this time, when the n different two-dimensional coordinate values are received from the key distribution processor 110, the ECU 1 (131) inputs the 'master key data 1' to the selected two- A master coordinate value 1 'can be generated.

Here, the 'master coordinate value 1' is one of the coordinate values used for generating the n-th polynomial in the polynomial generation unit 115, and is the n-dimensional coordinate value of the n received from the key distribution processing unit 110 The ECU 1 131 learns n + 1 coordinate values, which are conditions for generating the n-th order polynomial, since the first coordinate values are generated from the n-th order polynomial, By using the Lagrangian interpolation according to Equations 1, 2 and 3 based on n different two-dimensional coordinate values, the same polynomial as the n-th polynomial can be generated as the n-th polynomial for key detection.

When the ECU 1 (131) completes the generation of the n-th order polynomial for key detection, the ECU 1 (131) can calculate the session key K by applying '0' to the n-th polynomial for key detection as an input value. In this regard, since the key distribution processor 110 uses the basic two-dimensional coordinate value '(0, K)' to generate the n-th polynomial, the ECU 1 (131) The output value of 'K' can be obtained by inputting '0' as an input value to the n-th order polynomial for key detection after completion of generation of the key.

In this way, since the n ECUs 131, 132, 133, and 134 know the master key data that they have generated and store the selected two-dimensional coordinate generation function on the memory, 110), the master coordinate value is generated based on the master key data generated by each of the n-dimensional coordinate values, and then the master coordinate value is generated based on the master key data generated by each of the n-dimensional coordinate values, And by applying '0' to the n-th polynomial for key detection, the session key K can be calculated.

If the master key data generated by itself among the n ECUs 131, 132, 133 and 134 is lost or tampered, the corresponding ECU sends the n different two-dimensional It is impossible to generate the same n-degree polynomial as that of the n-th polynomial generated by the polynomial generation unit 115 because the master coordinate value can not be generated even if the coordinate value is received, Will not be distributed.

In this way, the n ECUs 131, 132, 133, and 134 can each generate and store the session key K in memory, so that when the session key K is stored in the memory, (131, 132, 133, 134) performs encryption of transmission data based on the session key K stored in the memory during data communication between the n ECUs 131, 132, 133, , And decrypts the received data, thereby performing secure communication.

According to an embodiment of the present invention, the two-dimensional coordinate generator 113 may generate n-dimensional coordinates through the master key data receiver 112 to enhance the security at the time of distributing the session key K Dummy data to be input as input together with each of the n master key data is randomly generated in the selected two-dimensional coordinate generating function when the n master key data is received from the master key data generating units (131, 132, 133, 134) Dimensional coordinate values, and generating the n two-dimensional coordinate values by applying each of the dummy data and the n master key data to the selected two-dimensional coordinate generation function as an input.

According to an embodiment of the present invention, the selected two-dimensional coordinate generating function may be a function calculated by the following equation (4).

는 상기 선정된 2차원 좌표 생성 함수로 n개의 ECU들(131, 132, 133, 134)로부터 상기 n개의 마스터 키 데이터들로 '(p, k)'의 형태를 갖는 데이터 쌍들이 수신되면, 2차원 좌표 생성부(113)는 상기 수학식 4에서 'R'로 표현된 더미 데이터를 랜덤하게 생성한 후 상기 n개의 마스터 키 데이터들 각각과 상기 더미 데이터 R을 상기 수학식 4의 상기 선정된 2차원 좌표 생성 함수에 입력으로 인가함으로써, '

'라고 하는 n개의 2차원 좌표 값들을 생성할 수 있다.In Equation (4)

When the data pairs having the form of '(p, k)' are received from the n ECUs 131, 132, 133, and 134 by the selected two-dimensional coordinate generating function with the n master key data, The dimensional coordinate generator 113 randomly generates dummy data represented by 'R' in Equation (4), and outputs each of the n master key data and the dummy data R to the selected 2 By applying as input to the dimensional coordinate generation function,

&Quot;,< / RTI >

'는 해시 함수, '

'은 두 데이터를 연속에서 나열하는 연접 기호이며, 'N'은 임의의 소수(prime number)이다. 이때, N은 랜덤하게 선택되는 소수이지만, 다항식 생성부(115)에서 생성되는 n차 다항식을 구성하는 계수를 제3자가 추측해서 맞출 확률을 낮추기 위해, 비교적 큰 값으로 선택되는 것이 바람직하다.here, '

'Is a hash function,'

'Is a concatenation symbol that lists two data in series, and' N 'is any prime number. At this time, N is a prime number to be selected randomly, but it is preferable to select a relatively large value in order to lower the probability that the third party guesses the third-order polynomial generated by the polynomial generation unit 115 and matches the probability.

When the two-dimensional coordinate generating unit 113 generates n two-dimensional coordinate values based on the selected two-dimensional coordinate generating function according to Equation (4), the basic two-dimensional coordinate generating unit 114 generates n Randomly generates a session key K to be distributed to the ECUs 131, 132, 133 and 134, generates basic two-dimensional coordinate values corresponding to '(0, K)' based on the session key K, The polynomial generating unit 115 may generate an n-th order polynomial using the Lagrangian interpolation according to Equations 1, 2, and 3 based on the basic two-dimensional coordinate value and the n two-dimensional coordinate values. Then, the additional coordinate generator 116 applies n different input values not included in the n two-dimensional coordinate values to the n-th polynomial, thereby generating n Two different two-dimensional coordinate values can be generated.

At this time, the key distribution processing unit 117 transmits all of the n different two-dimensional coordinate values to each of the n ECUs 131, 132, 133, and 134 and simultaneously transmits the dummy data, Distribution of K can be completed.

When the n different two-dimensional coordinate values and the dummy data are received from the key distribution processing unit 110, the n ECUs 131, 132, 133, and 134, respectively, The master key data generated by each of the n ECUs 131, 132, 133, and 134 and the dummy data received from the key distribution processing apparatus 110 are stored in the memory, As an input to generate the two-dimensional master coordinate value.

Then, each of the n ECUs 131, 132, 133, and 134 transmits the n different two-dimensional coordinate values and the n ECUs 131, 132, 133, and 134 received from the key distribution processing unit 110, Dimensional polynomial for key detection using Lagrange interpolation based on the generated two-dimensional master coordinate values, and applying '0' as an input value to the n-th order polynomial for key detection, And store it in the memory.

According to one embodiment of the present invention, the key distribution processing apparatus 110 includes an alternate key generation unit 118, an initialization unit 119, a two-dimensional coordinate reproducibility unit 120, a basic two-dimensional coordinate value reproducibility unit 121, A polynomial regenerating unit 122, an additional coordinate regenerating unit 123, and an alternative session key distribution processing unit 124. The polynomial regenerating unit 122,

If it is determined that the session key K is exposed to t (n is a natural number smaller than n) among the n ECUs 131, 132, 133, and 134, the substitute key generating unit 118 generates a session key K Since K is a key that is no longer usable, the dummy data and the session key K are discarded to issue a new session key to the ECUs other than the t ECUs, and the alternative dummy data and the alternative session key K K 'at random.

The initialization unit 119 initializes t master key data received from the t ECUs among the n master key data to random key data.

When the t master key data is initialized, the two-dimensional coordinate regenerator 120 generates the substitute dummy data and the n master key data (t master key data among the n master key data are random key data Are input to the selected two-dimensional coordinate generating function to regenerate n two-dimensional coordinate values.

The basic two-dimensional coordinate value regenerating unit 121 regenerates basic two-dimensional coordinate values corresponding to '(0, K') 'based on the substitute session key K'.

The polynomial regenerator 122 regenerates the n-th polynomial using Lagrangian interpolation based on the regenerated basic two-dimensional coordinate value and the regenerated n two-dimensional coordinate values.

The additional coordinate regenerating unit 123 applies n different input values that are not included in the regenerated n two-dimensional coordinate values to the regenerated n-th polynomial, thereby matching the regenerated n two-dimensional coordinate values And reproduces n different two-dimensional coordinate values that do not exist.

The alternative session key distribution processing unit 124 transmits all of the regenerated n different two-dimensional coordinate values to each of the n ECUs 131, 132, 133, and 134 and simultaneously transmits the alternative dummy data, The distribution of the alternative session key K 'is completed.

According to an embodiment of the present invention, each of the n ECUs 131, 132, 133 and 134 receives the regenerated n different two-dimensional coordinate values and the substitute dummy data from the key distribution processing apparatus 110 When received, the master key data generated by each of the n ECUs 131, 132, 133, and 134 and the substitute dummy data received from the key distribution processing apparatus 110 are stored in the memory The 2D master coordinate value can be regenerated by applying it as an input to the 2D coordinate generating function.

Each of the n ECUs 131, 132, 133, and 134 then receives the regenerated n other two-dimensional coordinate values received from the key distribution processing unit 110 and the n ECUs 131, 132, 133, 134) can regenerate the n-th order polynomial for key detection using Lagrangian interpolation based on the regenerated two-dimensional master coordinate values.

Thereafter, the n ECUs 131, 132, 133, 134 calculate the alternative session key K 'by applying' 0 'to the n-th polynomial for the regenerated key detection as an input value, Can be restored.

After the session key K is distributed to the n ECUs 131, 132, 133, and 134, the key distribution processing apparatus 110 according to the present invention transmits the session key K from the t ECUs , It issues a new alternative session key K 'to process the t ECUs so that they can no longer communicate in the communication session and only the remaining ECUs are allowed to communicate with the new session key, After initialization of the master key data received from the t ECUs to a random value, the master key data of the alternate session key K 'and the master key data of the n ECUs 131, 132, 133, Dimensional polynomial and regenerates n different two-dimensional coordinate values on the basis of the regenerated n-th polynomial, and transmits it again to the n ECUs 131, 132, 133, and 134.

At this time, the n ECUs 131, 132, 133, and 134 regenerate the n-th order polynomial for key detection based on the regenerated n different two-dimensional coordinate values and their master key data, The alternate session key K 'may be generated by applying' 0 'to the n-th polynomial as input. After the key distribution processing unit 110 initializes the master key data for the t ECUs to a random value The t ECUs of the n ECUs 131, 132, 133, and 134 attempt to regenerate the n-th order polynomial for key detection based on the master key data before being initialized in that the n-th polynomial is regenerated The key distribution processing apparatus 110 can not generate the n-degree polynomial for key detection identical to the regenerated n-degree polynomial and can not generate the alternative session key K '.

Therefore, the key distribution processing apparatus 110 according to the present invention issues a new session key only to the remaining ECUs except for the t ECUs out of the n ECUs 131, 132, 133, 134 in which the session key is exposed So that the remaining ECUs can perform secure communication with a new session key.

2 is a flowchart showing an operation method of a key distribution processing apparatus for processing distribution of a session key in an encrypted manner for ECUs mounted in a vehicle according to an embodiment of the present invention.

In step S210, when an instruction to distribute a session key to the n ECUs is given as n (n is a natural number equal to or greater than two) ECUs installed in the vehicle, the ECU is connected to the n ECUs And requests transmission of the master key data.

In step S220, when the n ECUs generate different master key data, when n master key data items different from each other are received from the n ECUs, the n master key data items are received.

In step S230, each of the n master key data is input to the selected two-dimensional coordinate generating function to generate n two-dimensional coordinate values.

In step S240, a session key K to be distributed to the n ECUs is randomly generated, and a basic two-dimensional coordinate value corresponding to '(0, K)' is generated based on the session key K.

In step S250, an n-th order polynomial is generated using Lagrange interpolation based on the basic two-dimensional coordinate value and the n two-dimensional coordinate values.

In step S260, n different two-dimensional coordinate values that do not coincide with the n two-dimensional coordinate values are applied to the n-th polynomial by applying n different input values not included in the n two- Lt; / RTI >

In step S270, distribution of the session key K is completed by transmitting all of the n different two-dimensional coordinate values for each of the n ECUs.

At this time, according to an embodiment of the present invention, each of the n ECUs stores the selected two-dimensional coordinate generation function on the memory, and when receiving a transfer request of the master key data from the key distribution processing device And transmits the master key data to the key distribution processing apparatus after receiving the n different two-dimensional coordinate values from the key distribution processing apparatus, Each master key data generated by each of the ECUs is input to the selected two-dimensional coordinate generating function stored in the memory to generate a two-dimensional master coordinate value, Based on the n different two-dimensional coordinate values and the two-dimensional master coordinate values generated by each of the n ECUs, using Lagrangian interpolation By applying a polynomial equation for generating the n-th key is detected, and "0" into the n-order polynomial for the key detected by the input value, it can be calculated by the session key K stored in the said memory.

According to an embodiment of the present invention, when the n master key data are received through step S220, the master key data is stored in the selected two-dimensional coordinate generating function, Dimensional coordinate values by randomly generating dummy data to be applied as input together and applying each of the dummy data and the n master key data to the selected two dimensional coordinate generation function as input have.

At this time, in step S270, distribution of the session key K can be completed by transmitting all of the n different two-dimensional coordinate values for each of the n ECUs and transmitting the dummy data together.

When each of the n ECUs receives the n different two-dimensional coordinate values and the dummy data from the key distribution processing device, each of the n ECUs receives the master key data generated by each of the n ECUs, Dimensional master coordinate value stored in the memory, and generates the two-dimensional master coordinate value by applying the input dummy data to the selected two-dimensional coordinate generation function stored in the memory.

In addition, according to an embodiment of the present invention, when the session key K is generated and stored on the memory, each of the n ECUs calculates a difference Encrypts the transmission data based on the session key K, and decrypts the received data.

In addition, according to an embodiment of the present invention, the operation method of the key distribution processing apparatus may be configured such that when it is determined that the session key K is exposed to t ECUs (t is a natural number smaller than n) among the n ECUs , Discarding the dummy data and the session key K, randomly generating substitute dummy data and an alternative session key K ', generating t master key data received from the t ECUs of the n master key data Initializing the t master key data with the random key data, and when the t master key data are initialized, the substitute dummy data and the n master key data (t master key data among the n master key data are random And initializing n 2-dimensional coordinate values by applying each input to the selected two-dimensional coordinate generating function, Based on the regenerated basic two-dimensional coordinate value and the regenerated n two-dimensional coordinate values, the basic two-dimensional coordinate value corresponding to '(0, K') ' Dimensional polynomial by regenerating an n-th polynomial using Lagrange interpolation, applying n different input values not included in the regenerated n 2-dimensional coordinate values to the regenerated n-th polynomial, Dimensional coordinate values that do not coincide with the dimensional coordinate values; and transmitting all of the regenerated n different two-dimensional coordinate values for each of the n ECUs and simultaneously transmitting the substitute dummy data together , And completing the distribution of the alternative session key K '.

According to an embodiment of the present invention, each of the n ECUs receives the regenerated n different two-dimensional coordinate values and the substitute dummy data from the key distribution processing device, Dimensional master coordinate value stored in the memory to generate the two-dimensional master coordinate value by applying each of the generated master key data and the substitute dummy data received from the key distribution processing apparatus to the selected two-dimensional coordinate generation function stored in the memory, Order n polynomial for key detection is regenerated using Lagrange interpolation based on the regenerated n other two-dimensional coordinate values received from the key distribution processing device and the two-dimensional master coordinate values regenerated by each of the n ECUs, By applying '0' as an input value to the regenerated n-degree polynomial for key detection, the substitute session key K 'is calculated, To be saved again.

The operation method of the key distribution processing apparatus according to the embodiment of the present invention has been described above with reference to FIG. Here, the operation method of the key distribution processing apparatus according to the embodiment of the present invention may correspond to the operation of the operation of the key distribution processing apparatus 110 described with reference to FIG. 1, so a detailed description thereof will be omitted .

A method of operating a key distribution processing apparatus according to an embodiment of the present invention may be implemented by a computer program stored in a storage medium for execution via a combination with a computer.

In addition, the operation method of the key distribution processing apparatus according to an embodiment of the present invention may be implemented in the form of a program command which can be executed through various computer means and recorded in a computer-readable medium. The computer-readable medium may include program instructions, data files, data structures, and the like, alone or in combination. The program instructions recorded on the medium may be those specially designed and constructed for the present invention or may be available to those skilled in the art of computer software. Examples of computer-readable media include magnetic media such as hard disks, floppy disks and magnetic tape; optical media such as CD-ROMs and DVDs; magnetic media such as floppy disks; Magneto-optical media, and hardware devices specifically configured to store and execute program instructions such as ROM, RAM, flash memory, and the like. Examples of program instructions include machine language code such as those produced by a compiler, as well as high-level language code that can be executed by a computer using an interpreter or the like.

As described above, the present invention has been described with reference to particular embodiments, such as specific elements, and specific embodiments and drawings. However, it should be understood that the present invention is not limited to the above- And various modifications and changes may be made thereto by those skilled in the art to which the present invention pertains.

Accordingly, the spirit of the present invention should not be construed as being limited to the embodiments described, and all of the equivalents or equivalents of the claims, as well as the following claims, belong to the scope of the present invention .

110: key distribution processing device
111: Key transmission request unit 112: Master key data reception unit
113: two-dimensional coordinate generating unit 114: basic two-dimensional coordinate generating unit
115: polynomial generating unit 116: additional coordinate generating unit
117: Key distribution processing unit 118: Alternative key generation unit
119: initialization unit 120: two-dimensional coordinate regeneration unit
121: basic two-dimensional coordinate value reproducibility part 122: polynomial regeneration part
123: additional coordinate reproduction unit 124: alternative session key distribution processing unit
131, 132, 133, 134: n ECUs

Claims (14)

A key distribution processing apparatus for processing distribution of a session key in an encrypted manner with respect to ECUs (Electronic Control Units) mounted in a vehicle,
(N is a natural number equal to or greater than two) ECUs installed in the vehicle, when a distribution command of the session key to the n ECUs is applied, the transmission of the master key data to the n ECUs A key transmission request unit for requesting a key transmission request;
A master key data receiving unit for receiving the n master key data when n master key data are transmitted from the n ECUs as each of the n ECUs generates different master key data;
A two-dimensional coordinate generator for generating n two-dimensional coordinate values by applying each of the n master key data to a selected two-dimensional coordinate generating function as an input;
A basic two-dimensional coordinate value generator for randomly generating a session key K to be distributed to the n ECUs and generating a basic two-dimensional coordinate value corresponding to '(0, K)' based on the session key K;
A polynomial generating unit for generating an n-th polynomial based on the basic two-dimensional coordinate value and the n two-dimensional coordinate values using Lagrange interpolation;
Dimensional coordinate values that do not coincide with the n two-dimensional coordinate values by applying n different input values that are not included in the n two-dimensional coordinate values to the n-th degree polynomial, Generating unit; And
A key distribution processing unit for completing distribution of the session key K by transmitting all of the n different two-dimensional coordinate values for each of the n ECUs,
The key distribution processing apparatus comprising: The method according to claim 1,
Each of the n ECUs
Dimensional master key data is stored in the memory, and when the master key data transmission request is received from the key distribution processing device, unique master key data is generated and stored in the memory, Transmits the key data to the key distribution processing apparatus,
When receiving the n different two-dimensional coordinate values from the key distribution processing device, inputting each master key data generated by each of the n ECUs to the selected two-dimensional coordinate generating function stored in the memory Dimensional master coordinate value, and generates a two-dimensional master coordinate value by using the Lagrangian interpolation method based on the n different two-dimensional coordinate values received from the key distribution processing device and the two-dimensional master coordinate value generated by each of the n ECUs Generates an n-th degree polynomial for key detection,
And applying '0' to the n-th order polynomial for key detection as an input value to calculate and store the session key K on the memory. 3. The method of claim 2,
The two-dimensional coordinate generator
When the n master key data is received through the master key data receiving unit, dummy data to be input together with each of the n master key data is randomly generated in the selected two-dimensional coordinate generating function Dimensional coordinate generating function to generate the n two-dimensional coordinate values by applying each of the dummy data and the n master key data to the selected two-dimensional coordinate generating function,
The key distribution processing unit
The distribution of the session key K is completed by transmitting all of the n different two-dimensional coordinate values for each of the n ECUs and transmitting the dummy data together,
Each of the n ECUs
When receiving the n different two-dimensional coordinate values and the dummy data from the key distribution processing device, the master key data generated by each of the n ECUs and the dummy data received from the key distribution processing device, Dimensional master coordinate value stored in the storage unit as an input to the selected two-dimensional coordinate generation function stored in the storage unit. 3. The method of claim 2,
Each of the n ECUs
When the session key K is generated and stored in the memory, encryption of transmission data is performed based on the session key K stored in the memory during data communication between the n ECUs, And decrypts the encrypted key. The method of claim 3,
If it is determined that the session key K is exposed to t (n is a natural number smaller than n) of the n ECUs, the dummy data and the session key K are discarded, and alternative dummy data and an alternative session key An alternative key generation unit for randomly generating K ';
An initialization unit for initializing t master key data received from the t ECUs among the n master key data to random key data;
When the t master key data are initialized, the replacement dummy data and the n master key data - t master key data among the n master key data are data initialized with random key data - A two-dimensional coordinate regenerator for regenerating n two-dimensional coordinate values as an input to the selected two-dimensional coordinate generating function;
A basic two-dimensional coordinate value regenerator for regenerating basic two-dimensional coordinate values corresponding to '(0, K') 'based on the alternative session key K';
A polynomial regenerator for regenerating an n-th polynomial using Lagrangian interpolation based on the regenerated basic two-dimensional coordinate value and the regenerated n two-dimensional coordinate values;
By applying n different input values that are not included in the regenerated n two-dimensional coordinate values to the regenerated n-th polynomial, n different two-dimensional coordinates that do not match the regenerated n two- An additional coordinate regenerator for regenerating the values; And
An alternative session key distribution processing unit for completing the distribution of the alternative session key K 'by transmitting all of the regenerated n different two-dimensional coordinate values for each of the n ECUs,
Further comprising: 6. The method of claim 5,
Each of the n ECUs
When the regenerated n different two-dimensional coordinate values and the substitute dummy data are received from the key distribution processing device, the master key data generated by each of the n ECUs and the substitute dummy data received from the key distribution processing device Dimensional coordinate generating function stored in the memory to generate a two-dimensional master coordinate value,
The n-dimensional polynomial for key detection is regenerated using Lagrange interpolation based on the regenerated n different two-dimensional coordinate values received from the key distribution processing device and the two-dimensional master coordinate values regenerated by each of the n ECUs ,
And applying '0' as an input value to the regenerated n-th order polynomial for detecting the key, thereby calculating the alternative session key K 'and restoring the alternative session key K' on the memory. A method of operating a key distribution processing apparatus for processing distribution of a session key in an encrypted manner with respect to ECUs (Electronic Control Units) mounted in a vehicle,
(N is a natural number equal to or greater than two) ECUs installed in the vehicle, when a distribution command of the session key to the n ECUs is applied, the transmission of the master key data to the n ECUs ;
Receiving n master key data when n master key data are transmitted from the n ECUs as each of the n ECUs generates different master key data;
Generating n two-dimensional coordinate values by applying each of the n master key data to a selected two-dimensional coordinate generation function as input;
Randomly generating a session key K to be distributed to the n ECUs, and generating a basic two-dimensional coordinate value corresponding to '(0, K)' based on the session key K;
Generating an n-th order polynomial using Lagrange interpolation based on the basic two-dimensional coordinate value and the n two-dimensional coordinate values;
Generating n different two-dimensional coordinate values that do not coincide with the n two-dimensional coordinate values by applying n different input values that are not included in the n two-dimensional coordinate values to the n-th polynomial; And
Completing the distribution of the session key K by transmitting all of the n different two-dimensional coordinate values for each of the n ECUs
To the key distribution processing apparatus. 8. The method of claim 7,
Each of the n ECUs
Dimensional master key data is stored in the memory, and when the master key data transmission request is received from the key distribution processing device, unique master key data is generated and stored in the memory, Transmits the key data to the key distribution processing apparatus,
When receiving the n different two-dimensional coordinate values from the key distribution processing device, inputting each master key data generated by each of the n ECUs to the selected two-dimensional coordinate generating function stored in the memory Dimensional master coordinate value, and generates a two-dimensional master coordinate value by using the Lagrangian interpolation method based on the n different two-dimensional coordinate values received from the key distribution processing device and the two-dimensional master coordinate value generated by each of the n ECUs Generates an n-th degree polynomial for key detection,
And applying '0' to the n-th order polynomial for key detection as an input value, the session key K is computed and stored in the memory. 9. The method of claim 8,
Wherein the generating the n two-dimensional coordinate values comprises:
Wherein when the n master key data is received through receiving the n master key data, dummy data to be input as input together with each of the n master key data is added to the selected two- Generating the n two-dimensional coordinate values by applying each of the dummy data and the n master key data to the selected two-dimensional coordinate generating function as an input,
The step of completing the distribution of the session key K
The distribution of the session key K is completed by transmitting all of the n different two-dimensional coordinate values for each of the n ECUs and transmitting the dummy data together,
Each of the n ECUs
When receiving the n different two-dimensional coordinate values and the dummy data from the key distribution processing device, the master key data generated by each of the n ECUs and the dummy data received from the key distribution processing device, Dimensional master coordinate value stored in the storage unit as an input to the selected two-dimensional coordinate generation function stored in the storage unit. 9. The method of claim 8,
Each of the n ECUs
When the session key K is generated and stored in the memory, encryption of transmission data is performed based on the session key K stored in the memory during data communication between the n ECUs, Wherein the key distribution processing unit performs the decryption on the key distribution processing apparatus. 10. The method of claim 9,
If it is determined that the session key K is exposed to t (n is a natural number smaller than n) of the n ECUs, the dummy data and the session key K are discarded, and the alternative dummy data and the alternative session key Randomly generating K ';
Initializing t master key data received from the t ECUs among the n master key data with random key data;
When the t master key data are initialized, the replacement dummy data and the n master key data - t master key data among the n master key data are data initialized with random key data - Applying the selected two-dimensional coordinate generation function as an input to regenerate n two-dimensional coordinate values;
Reproducing the basic two-dimensional coordinate value corresponding to '(0, K') 'based on the alternative session key K';
Regenerating an n-th order polynomial using Lagrangian interpolation based on the regenerated basic two-dimensional coordinate value and the regenerated n two-dimensional coordinate values;
By applying n different input values that are not included in the regenerated n two-dimensional coordinate values to the regenerated n-th polynomial, n different two-dimensional coordinates that do not match the regenerated n two- Regenerating the values; And
Completing the distribution of the alternate session key K 'by transmitting all of the regenerated n different two-dimensional coordinate values for each of the n ECUs and simultaneously transmitting the alternate dummy data
Further comprising the steps of: 12. The method of claim 11,
Each of the n ECUs
When the regenerated n different two-dimensional coordinate values and the substitute dummy data are received from the key distribution processing device, the master key data generated by each of the n ECUs and the substitute dummy data received from the key distribution processing device Dimensional coordinate generating function stored in the memory to generate a two-dimensional master coordinate value,
The n-dimensional polynomial for key detection is regenerated using Lagrange interpolation based on the regenerated n different two-dimensional coordinate values received from the key distribution processing device and the two-dimensional master coordinate values regenerated by each of the n ECUs ,
Calculating an alternative session key K 'by applying' 0 'as an input value to the regenerated n-degree polynomial for detecting the key, and restoring it on the memory. A computer-readable recording medium storing a program for causing a computer to perform the method according to any one of claims 7 to 12. 13. A computer program stored in a storage medium for executing the method of any one of claims 7 to 12 through a combination with a computer.

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