KR200381459Y1 - Locking apparatus for using cipher algorithm - Google Patents

Abstract

The present invention relates to a locking device using a highly secure encryption algorithm such as a portable safe device such as a portable safe, a portable terminal device, and a fixed lock device such as a residence, a car, a fixed safe, and the like.

To this end, the present invention, a key that stores the encryption key generated by a predetermined encryption algorithm and the signal of the key, and if the received signal is a signal for unlocking the lock device by decrypting the encryption key When the received signal is a signal for key filling and key updating, a lock using a cryptographic algorithm including a key maker for generating a new encryption key is provided.

Description

LOCKING APPARATUS FOR USING CIPHER ALGORITHM}

The present invention relates to a lock device, and more particularly, to a lock device using a highly secure encryption algorithm such as a portable safe device such as a portable safe, a mobile terminal device, and a fixed lock device such as a residence, a car, a fixed safe, and the like. It is about.

In general, the door of a building, a safe or a car is locked with a mechanical lock, and unlocked with a key corresponding thereto.

However, these mechanical keys are easy to replicate and are highly likely to be used illegally, and the lock can also be easily unlocked by a person with some technical skills, so it is vulnerable to security.

Recently, in order to secure the shortcomings of the mechanical lock, a locking device using biometric identification means such as a fingerprint or an iris has been developed and proposed. However, the raw vegetable identification means also has the disadvantage that a huge cost to build equipment and equipment.

In addition, encryption algorithms using a linear feedback shift register (LFSR) are also widely used. However, LFSR has a disadvantage in that it is easily predictable (decryption) from an output sequence due to their linearity.

That is, for the LFSR of length L, the complete period of the key sequence is obtained from the successive L term of the sequence if the feedback polynomial is known, and from the 2L term if not known.

The present invention was devised to solve the above-mentioned problems, and randomly clocked the LFSR through a clock adjusting function, and then generated a key sequence bit output, thereby increasing the nonlinearity of the generated key to increase the correlation attack. It is an object of the present invention to provide a locking device using a cryptographic algorithm that makes it difficult to decrypt such a password.

In order to achieve the above object, according to an aspect of the present invention, a key storing an encryption key generated by a predetermined encryption algorithm; When the signal of the key is received and the received signal is a signal for unlocking, the encryption device is decrypted to release the lock, and if the received signal is a signal for key filling and key updating, a new encryption key. It provides a lock using a cryptographic algorithm comprising a key maker to generate a.

In addition, the predetermined encryption algorithm is characterized by generating a carry, memory and key sequence bit output after randomly clocking the LFSR through a clock adjustment function.

In addition, the predetermined encryption algorithm is characterized by having two mutually clocked LFSRs, a carry and a memory bit.

Also, the two LFSRs randomly control clocks of different LFSRs to generate an irregular clock in each register. The LFSR irregular clock on one side is randomly determined according to the contents of two specific taps of the other LFSR. It features.

The apparatus may further include a key reader that reads an encryption key stored in the key and transmits the encrypted key to the key maker.

The key maker may include a key generation unit for generating a key using the predetermined encryption algorithm, a key encryption unit for generating an encryption key through an exclusive logical OR of a key generated from the key generation unit and plain text, And a key decryption unit generating a plain text by repeating an exclusive logical OR twice using a key generated from the key generation unit, and a control unit which generates an encryption key or generates a plain text by controlling the key generation unit according to the received signal. It is characterized by.

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

The cryptographic algorithm according to the present invention is largely composed of a summation sequence key generation, an encryption and a decryption process. FIG. 1 is a block diagram illustrating a summation sequence key generation process in the encryption algorithm according to the present invention.

Referring to FIG. 1, a process of generating a sum sequence key, loading a key, and updating a key through clock control will be described.

1. The process of generating the sum sequence key

The encryption algorithm according to the present invention may be configured in the form of an LM sum sequence generator with r = 2 having two LFSRs and one bit memory (input) of c _j-1 and d _j-1 .

Here, two LFSRs are denoted by L _a and L _b , a carry bit is denoted by c, and a memory bit added to correspond to Meier attack and Dawson attack is denoted by d.

At j, a _j and b _j are the outputs of LFSR L _a and L _b (the 1-bit output of L _a is denoted as a _j , and the 1-bit output of L _b denoted as b _j ), output at time j z _j is _defined by f _z , carry state c _j is _defined by f _c , and memory state d _j is defined by f _d .

Here, the output function f _z outputs a key sequence bit z _j , the remaining bits are carry bits and stored in memory, and carry sequence c _j and d _j Is used as input to the combining function to generate the next bit.

Therefore, the output key sequence of the encryption algorithm is generated by combining the LFSR sequence with the carry and memory sequences.

In addition, the encryption algorithm has two mutually clock-controlled LFSRs and a carry and memory bits, and the lengths of the LFSRs are 127 bits and 129 bits, respectively. All the memory bits provide the cryptographic algorithm with 258 bits of internal status bits, which are filled in by the 128-bit key and the 128-bit initialization vector.

The return polynomials of L _a and L _b are respectively selected from the following equations (1) (2) of the primitive polynomials p _a (x) and p _b (x), and all bits of the LFSR are all zero state: Do not allow initialization to

Here, the random number is equal to the exponent value of x and the tap number of the LFSR, and Equation (1) and (2) indicate the number of taps to be fed back, and the number of taps is fed back to increase security. .

In addition, the carry function f _c , the output function f _z , and the memory function f _d are defined as follows.

Here, j-1 means a previous time clock and j means a current time clock.

In addition, equation (3) (4) (5) represents the full adder of the exclusive OR (XOR) value, for example, the input is a _j = 1, b _j = 1, c _j-1 = 1 With a value of, the output will have a binary 11 value of c _j = 1 and z _j = 1.

Thus, the output key sequence bits z _j , The carry bits c _j and the memory bits d _j take the same form as the LM sum sequence generator in structure, but the output sequence and the level of the performance are greatly improved.

2. Clock control

The cryptographic algorithm according to the present invention may be configured in the form of a sum sequence generator with the addition of a mutual clock adjustment structure.

In this way, the LFSR is supplied with an irregular clock, and the irregular clock of the LFSR is randomly determined by the contents of two specific taps of the remaining LFSR.

That is, in the cryptographic algorithm according to the present invention, two LFSRs randomly control the clocks of different LFSRs to generate an irregular clock in each register, and two taps are obtained from L _a to calculate a range of 1 to 4 values. , L _b is fed back by a random number of 1 to 4 clocks.

Similarly, we control the clock of L _a after obtaining a random value ranging from 1 to 4 from the two tap values of L _b .

As such, the number of irregular clocks supplied to one LFSR is obtained from the clock adjustment functions f _a or f _b generated in the remaining LFSRs, and the clock adjustment functions f _a and f _b are represented by Equations (6) and (7). Is defined as:

An example of an irregular clock supply through the clock adjustment functions f _a and f _b is as follows.

Clock adjustment value if general irregular value of from 1 to 4 come out is obtained from a particular tap, for example, the value from the two tabs (42, 85) of the L _a (1, 0) is f _a (L _a) = 2 * 1 + 0 * 1 + 1 = 3

In this way, if the value of two taps is (0, 0), it is 1 clock, if it is (0, 1), it is 2 clocks, if it is (1, 0) it is 3 clocks, and if it is (1, 1) 4 clocks are moved. Decryption is difficult because the value of the tap is unpredictable.

Since clock control moves the other LFSR by the number of clocks read from the two taps, if the value of the two taps 42 and 85 in L _a is (1, 0), L _b is moved by three clocks.

In addition, when the values of the two taps 43 and 86 at L _b are (0, 1), L _a is shifted by two clocks.

In this way, if one output is obtained after moving both LFSRs, a binary random value is obtained. Therefore, to obtain a 1024-bit random value, the process is repeated 1024 times.

Therefore, the clock adjustment functions f _a and f _b randomly clock the LFSR and then generate the carry, memory, and key sequence bit outputs, thereby increasing the password stealth and stability.

3. Key Loading and Key Updates

Key loading is used to initially give a secret key and get random output, and key update allows the key to be updated as needed.

That is, in a communication system, a synchronous error requires retransmission of the entire message (or remaining messages), and in the case of synchronous stream cipher, another key sequence should be used for safety.

For this purpose, key rekeying should be a method of resynchronizing the initial vector (iv) to be transmitted with the secret key (k) in plain text state, or another public method.

In the cryptographic algorithm according to the present invention, initial key loading and key update are performed as follows.

In the encryption algorithm according to the present invention, the initial state is filled from the key (k) and the initialization vector (iv, initial key), and the key expansion process for filling the internal state is performed because the internal state length is longer than the key length. Required.

In addition, both the key k and the initialization vector iv are 128 bits long, and the key and initialization vector fill the 256-bit internal state (the initial carry and memory are initialized to '0').

Here, the initial value may be regarded as a key as needed, or may be set as a fixed value forever. In the present invention, the initial value is regarded as a key and is set as a 128 bit key and a 256 bit key of a 128 bit initial value.

In addition, the encryption algorithm has two mutually clock controlled LFSRs (L _a , L _b ) and carry and memory bits, and the lengths of the LFSRs are 127 bits and 129 bits, respectively. All memory bits provide the cryptographic algorithm with 258 bits of internal status bits, which are filled in by the 128-bit key (k) and the 128-bit initialization vector (iv).

In addition, the initial setting process can be used for a key update, the process of generating the initial state of the key stream generator uses the generator itself twice, and the start state of the L _a is simply by a logical exclusive sum (XORing) L _a = (k iv) as mod 2 ¹²⁷

The 129-bit initial state for L _b is taken from the 128-bit key and shifted 1 bit to the left, including the internal 129-bit word.

The initial vector is then logically summed (XORing) with 0 and an internal 129-bit word, that is, L _b = (k << 1) (0 | iv). Once the key and initial vector are set, the cryptographic algorithm is run to generate a 258-bit long sequence of keys twice, and then the 258 bits are used to reinitialize the two LFSRs and carry bits as follows. That is, the first 127 bits set the initial state of L _a , the next 129 bits set the initial state of L _b , and the carry bits (c ₀ , d ₀ ) with the remaining 2 bits. At this time, any one LFSR should not be initialized to 0-vector.

This reinitialization shows that the best attack on the key renewal process is an exhaustive key-search attack because of the high security of the encryption algorithm.

2 is a block diagram illustrating an encryption process and a decryption process in an encryption algorithm according to the present invention.

As shown in FIG. 2, the key bit sequence (hereinafter, referred to as key) k and plaintext m generated through the key generator (inter-clock-controlled LM sum sequence generator) shown in FIG. Generate an encryption key C through eXclusive OR (C = E _k (m)).

In addition, the key k generated through the same key generation unit disposed at the transmitting and receiving end is repeated twice exclusively with the transmitting and receiving end (XOR (XOR)) so that the encrypted key is decrypted to obtain a plain text (m = D _k). (C)).

Here, the plain text may correspond to a signal for releasing the locking device.

Figure 3a is a functional block diagram showing the configuration of the locking device 100 using the encryption algorithm according to the present invention, Figure 3b is a functional block diagram showing the main configuration for the key maker 130.

As shown in FIG. 3A, the locking device 100 using the encryption algorithm according to the present invention includes a key 110, a key reader 120, a key maker 130, and a locking device 140.

Here, the key 110 is stored in the encryption key (k) generated by the encryption algorithm of the present invention, this key 110 is produced in a simple design and easy to carry in a variety of designs.

In addition, the key reader 120 recognizes the key 110, reads the password stored in the key 110 and transmits it to the key maker 130.

In addition, the key maker 130 decrypts the cipher of the key 110 read by the key reader 120 and outputs an unlocking signal to the locking device based on the decrypted result.

In addition, the key maker 130 generates an encryption key for key filling to generate a new encryption key on a key that is not input or a key update to update an existing encryption key, and transmits the encryption key to the key 110.

In addition, the locking device 140 may be implemented as a locking device of various types, such as mechanical or electronic in the form of a general door lock device.

Here, the connection standard of the key 110, the key reader 120, the key maker 130 may be applied to the RS-232C serial port method, USB port method and contact / contactless smart card method.

In addition, the key 110, and the key maker 130 may be composed of a small microprocessor for controlling the key lock and unlock through the encryption key and the memory of the EEPROM that stores the encryption key, the key reader is It may be configured as a memory of the stored EEPROM.

As shown in FIG. 3B, the key maker 130 is a control unit 131 that controls the key generation unit 132, the key encryption unit 133, the key decryption unit 134, and the key generation unit 132. It is composed.

Here, the controller 131 receives a signal transmitted through the key reader 132, and in the case of a signal for unlocking, releases the lock device through the key generator 132 and the key decoder 134. In the case of a signal for key update and key filling, an encryption key is generated through the key generator 132 and the key encryptor 133.

That is, when the user's key 110 is authenticated (if the user is authenticated as an encryption key user), since there is already the same key generated through the key generation unit 132 according to the encryption algorithm according to the present invention, the key is used. The decryption unit 134 releases the lock.

On the other hand, when a new encryption key needs to be generated as an authenticator (authenticated as an encryption key user) or a key update is necessary due to a synchronization error in a communication system, a new key is generated through the key generation unit 132, and By using the key encryption unit 133 to generate an encryption key.

The key generation unit 132 generates a key using an encryption algorithm according to the present invention shown in FIG.

The key encryptor 133 generates an encryption key through an exclusive logical OR of the key generated from the key generator 132 and the plain text (see FIG. 2).

The key decryption unit 133 generates the plain text by repeating the exclusive OR twice (XOR (XOR)) using the key generated from the key generation unit 132 (see FIG. 2).

Here, the plain text may correspond to a signal for releasing the locking device.

Accordingly, the key 110 encrypted and transmitted by the key encryption unit 133 of the key maker 130 and the key 110 decrypted by the key decryption unit 134 are compared to be recognized as an approved key and locked. The lock device 140 is released by outputting a release signal.

In addition, the key reader 120 and the key maker 130 may be integrally implemented. In this case, the key reader 110 may be implemented in the form of an embedded reader chip (SoC) for Bluetooth communication or RF wireless communication. .

4 is a perspective view showing the locking device 100 using an encryption algorithm according to the present invention.

As shown in FIG. 4, the key reader 120 is located outside the door 180 and the key maker 130 is located inside.

In addition, since the key maker 130 performs the function of generating the encryption key and filling the encryption key to the key 110 in which the encryption key is not input, the key maker 130 is provided as a separate protective case 150. Only authorized users who are covered and opened inside the door can generate the encryption key when the key is generated, filled, and lost, thereby recharging the remaining key to eliminate the risk of the lost key.

In addition, if the key is recognized through the key reader 120, if it is an authenticated key, the key is decrypted through the keymaker 130 to unlock the door to open the door, so only the authenticated user can access the door, thereby improving security. You can.

In addition, although the door lock device has been described, the present invention is not limited thereto and may be applied to various types of lock devices such as a portable safe device such as a portable safe and a portable terminal device and a fixed type lock device such as a residence, a car, and a fixed safe. .

As described above, the locking device using the encryption algorithm according to the present invention improves the degree of nonlinearity by improving the nonlinearity by controlling the clock of the LM sum sequence generator.

In addition, when n = 256, the period can be 2 ¹²⁸ or more and the linear complexity can be 2 ¹²⁸ or more, and it can be seen that the basic random test item satisfies well.

Through this, it can be applied to next generation mobile communication, satellite communication, or various network communication requiring high speed.

While a specific embodiment of the locking device using the encryption algorithm according to the present invention has been described above, this is for illustrative purposes, and those skilled in the art will appreciate that various modifications may be made without departing from the technical spirit of the present invention. It will be possible, which will belong to the scope of the present invention.

As described above, the locking device using the cryptographic algorithm according to the present invention randomly clocks the LFSR through a clock adjusting function, and then increases the nonlinearity of the generated key by generating a key sequence bit output. Security can be enhanced by making it difficult to decrypt.

In addition, the locking device using the encryption algorithm according to the present invention has a 128-bit key, a 128-bit initial vector, and an internal state of 258 bits, and can maintain a 128-bit degree of confidentiality.

Through this, the cycle will be ²¹²⁸ or more, it is possible to implement the linear complexity of ²¹²⁸ or more, in many mobile communication, satellite communication or the various network applications that require a high speed is possible.

1 is a block diagram showing a process of generating a sum sequence key in an encryption algorithm according to the present invention.

2 is a block diagram illustrating an encryption process and a decryption process in an encryption algorithm according to the present invention.

Figure 3a is a functional block diagram showing the configuration of the locking device using the encryption algorithm according to the present invention, Figure 3b is a functional block diagram showing the main configuration for the key maker.

4 is a perspective view showing a locking device using an encryption algorithm according to the present invention.

<Description of Major Symbols in Drawing>

110: key 120: key reader

130: key maker 131: control unit

132: key generation unit 133: key encryption unit

134: key decryption unit 140: locking device

150: protective case 180: door

Claims (6)

A key storing an encryption key generated by a predetermined encryption algorithm, When the signal of the key is received and the received signal is a signal for unlocking, the encryption device is decrypted to release the lock, and if the received signal is a signal for key filling and key updating, a new encryption key. A lock using a cryptographic algorithm, characterized in that it comprises a key maker for generating a. The method of claim 1, The predetermined encryption algorithm is a lock device using a cryptographic algorithm, characterized in that for randomly clocked the LFSR through a clock adjustment function, and generates a carry, memory and key sequence bit output. The method of claim 2, And the predetermined encryption algorithm comprises two mutually clock-controlled LFSRs, a carry and a memory bit. The method of claim 3, wherein The two LFSRs randomly control the clocks of different LFSRs to generate an irregular clock in each register. The LFSR irregular clock of one side is randomly determined according to the contents of two specific taps of the other LFSR. Locking device using cryptographic algorithm. The method of claim 1, And a key reader for reading the encryption key stored in the key and transmitting the encrypted key to the key maker. The method of claim 1, The key maker includes a key generation unit for generating a key using the predetermined encryption algorithm, a key encryption unit for generating an encryption key through an exclusive logical OR of a key generated from the key generation unit and plain text, and the key generation. And a key decryption unit generating a plaintext by repeating an exclusive logical OR twice using a key generated from the unit, and a controller configured to generate an encryption key or generate plaintext by controlling a key generation unit according to a received signal. Locking device using cryptographic algorithm.