Encryption system and method based on LFSR and hyperchaotic system

Abstract

The invention relates to the technical field of information encryption and signal processing, and discloses an encryption system and method based on an LFSR and a hyperchaotic system, and the system comprises an LFSR module, a control module, and a hyperchaotic system module. Wherein the LFSR module is used for generating a pseudorandom sequence as an initial condition and a possible interference value of the hyperchaotic system module; the control module is used for controlling the output of the LFSR module and determining whether to perform external interference on the hyperchaotic system module; the hyperchaotic system module receives the initial condition generated by the LFSR module, operates to generate an encryption factor, and can receive external interference according to an instruction of the control module. According to the encryption system and method based on the LFSR and the hyperchaotic system, different types of non-repeated encryption factors can be quickly generated. And the hyperchaotic system can be interfered at any time in the encryption factor generation process, so that the randomness of the encryption factor is further improved. Therefore, the current encryption requirement on information security is met.

Description

Technical Field

[0001] The present invention relates to the technical field of information encryption and signal processing, and in particular to an encryption system and method based on LFSR and hyperchaotic system. Background Art

[0002] At present, the main method used at home and abroad to design analog circuits to generate chaotic signals is to use discrete components. However, since the parameters of analog circuit components are affected by environmental factors such as temperature and aging, and the chaotic system is extremely sensitive to the initial value, the effect of using analog circuits to realize chaotic systems is very limited.

[0003] However, digital circuits do not have device temperature and aging problems, and device parameters will not affect the results. The implementation effect is more ideal than that of analog circuits. Therefore, using digital circuits to implement chaotic systems has become the mainstream at this stage.

[0004] At present, chaotic systems have been realized by digital circuits, but due to the complexity of the dynamic characteristics of hyperchaotic systems, the digital circuit design of hyperchaotic systems has rarely been reported. Now, with the increasing requirements for information security, the encryption method based on the existing chaotic circuit can no longer meet the requirements. Summary of the invention

[0005] In view of the deficiencies in the prior art, the present invention proposes an encryption system and method based on LFSR and hyperchaotic system to solve the above technical problems.

[0006] Firstly, an encryption system based on LFSR and hyperchaotic system is provided, including:

[0007] LFSR module, control module and hyperchaotic system module;

[0008] Among them, the LFSR module is used to generate a pseudo-random sequence as the initial condition and possible interference value of the hyperchaotic system module;

[0009] The control module is used to control the output of the LFSR module and decide whether to perform external interference on the hyperchaotic system module;

[0010] The hyperchaotic system module receives the initial conditions generated by the LFSR module, runs to generate encryption factors, and can receive external interference according to the instructions of the control module.

[0011] Furthermore, the circuit structure of the LFSR module is based on a mathematical characteristic polynomial, including:

[0012] G(X)=g m X m +g m-1 X m-1 +g m-2 X m-2+…+g2X2+g10X+g0;

[0013] Where gm to g0 are coefficients, X is the variable, and m is the highest-order exponent of the polynomial.

[0014] Furthermore, the LFSR module is 32 bits, and each new value generated is a state.

[0015] Furthermore, the high-order 16-bit data output by the LFSR module is used as the initial condition value and interference value of the hyperchaotic system module.

[0016] Furthermore, the hyperchaotic system module is implemented using a modified Euler algorithm.

[0017] Furthermore, the control module controls whether to select the random data generated by the LFSR module as the interference value of the hyperchaotic system module through the input signal in_o.

[0018] Furthermore, the control module also controls whether to use external data as the initial condition value, interference value and encryption key of the hyperchaotic system module through input signals d and en;

[0019] If external data is not selected as the encryption key, the encryption key automatically generated by the system will be used and output.

[0020] In a second aspect, an encryption method based on LFSR and hyperchaotic system is provided, characterized in that the encryption system based on LFSR and hyperchaotic system described in any one of the above includes the following steps:

[0021] Control the LFSR module to generate a pseudo-random sequence through the control module;

[0022] The high 16-bit data output by the LFSR module is used as the initial condition of the hyperchaotic system module;

[0023] The hyperchaotic system module operates according to the initial conditions and generates encryption factors;

[0024] According to the needs, the control module decides whether to conduct external interference to the hyperchaotic system module;

[0025] Output the encryption factor and the corresponding encryption key.

[0026] Furthermore, it also includes receiving external input signals through the control module to determine whether to use external data as initial conditions, interference values ​​and encryption keys of the hyperchaotic system module.

[0027] The invention adopting the above technical solution has the following advantages:

[0028] The present invention aims to realize an encryption system and method based on LFSR and hyperchaotic system, which has the characteristics of both and can quickly generate different types of non-repetitive encryption factors.

[0029] In addition, the hyperchaotic system can be disturbed at any time during the process of generating encryption factors to further improve the randomness of the encryption factors, thereby solving the current encryption needs for information security. BRIEF DESCRIPTION OF THE DRAWINGS

[0030] In order to more clearly illustrate the specific implementation of the present invention, the following will briefly introduce the drawings required for use in the specific implementation. In all the drawings, each element or part is not necessarily drawn according to the actual scale.

[0031] Figure 1 The circuit structure diagram of the LFSR module in the encryption system based on the LFSR and hyperchaotic system of the present invention;

[0032] Figure 2 The actual circuit structure diagram of the LFSR module in the encryption system based on the LFSR and hyperchaotic system of the present invention;

[0033] Figure 3 The actual circuit structure diagram of the hyperchaotic system module in the encryption system based on LFSR and hyperchaotic system of the present invention;

[0034] Figure 4 It is an actual circuit structure diagram of the control module in the encryption system based on LFSR and hyperchaotic system of the present invention;

[0035] Figure 5 This is a simulation diagram of the encryption system and method based on LFSR and hyperchaotic system of the present invention, in which in_o is not controlled and input signals d and en are not selected for control;

[0036] Figure 6 It is a graphical display of the encryption system and method based on LFSR and hyperchaotic system of the present invention, in which in_o is not controlled and input signals d and en are not selected for control;

[0037] Figure 7 The present invention is based on the LFSR and hyperchaotic system encryption system and method to control the simulation of in_o Figure 1 ;

[0038] Figure 8 A drawing showing the control of in_o in the encryption system and method based on LFSR and hyperchaotic system of the present invention;

[0039] Fig. 9 The present invention is based on the LFSR and hyperchaotic system encryption system and method to control the simulation of in_o Figure 2 ;

[0040] Fig.10 The second drawing shows the control of in_o in the encryption system and method based on LFSR and hyperchaotic system of the present invention;

[0041] Fig.11 The present invention is based on the encryption system and method of LFSR and hyperchaotic system, which does not control in_o but is controlled by input signals d and en. Figure 3 ;

[0042] Fig.12 The present invention is based on the encryption system and method of LFSR and hyperchaotic system, which does not control in_o but is controlled by input signals d and en. Figure 4 ;

[0043] Fig.13 The third drawing shows that in_o is not controlled but controlled by input signals d and en in the encryption system and method based on LFSR and hyperchaotic system of the present invention;

[0044] Fig.14 FIG4 is a drawing showing the encryption system and method based on LFSR and hyperchaotic system of the present invention, in which in_o is not controlled but controlled by input signals d and en. DETAILED DESCRIPTION

[0045] The following embodiments of the technical solution of the present invention are described in detail in conjunction with the accompanying drawings. The following embodiments are only used to more clearly illustrate the technical solution of the present invention, and are therefore only used as examples, and cannot be used to limit the protection scope of the present invention.

[0046] It should be noted that, unless otherwise specified, the technical terms or scientific terms used in this application should be the common meanings understood by technicians in the field to which the present invention belongs. The terms "first", "second", etc. in the specification and claims of the embodiments of the present disclosure and the above-mentioned drawings are used to distinguish similar objects, and are not necessarily used to describe a specific order or sequence. It should be understood that the data used in this way can be interchanged where appropriate, so as to implement the embodiments of the present disclosure described here. In addition, the terms "including" and "having" and any of their variations are intended to cover non-exclusive inclusions. Unless otherwise specified, the term "multiple" means two or more. In the embodiments of the present disclosure, the character " / " indicates that the objects before and after are in an "or" relationship. For example, A / B means: A or B. The term "and / or" is a description of the association relationship of objects, indicating that there can be three relationships. For example, A and / or B means: A or B, or, A and B. The term "corresponding" can refer to an association relationship or a binding relationship, and A and B correspondingly refer to an association relationship or a binding relationship between A and B.

[0047] like Figure 1 to Figure 14 As shown, the encryption system based on LFSR and hyperchaotic system of the present invention comprises:

[0048] LFSR module, control module and hyperchaotic system module;

[0049] Among them, the LFSR module is used to generate a pseudo-random sequence as the initial condition and possible interference value of the hyperchaotic system module;

[0050] The control module is used to control the output of the LFSR module and decide whether to perform external interference on the hyperchaotic system module;

[0051] The hyperchaotic system module receives the initial conditions generated by the LFSR module, runs to generate encryption factors, and can receive external interference according to the instructions of the control module.

[0052] Specifically, the present invention aims to realize an encryption system and method based on LFSR and hyperchaotic system, which has the characteristics of both and can quickly generate different types of non-repetitive encryption factors.

[0053] In addition, the hyperchaotic system can be disturbed at any time during the process of generating encryption factors to further improve the randomness of the encryption factors, thereby solving the current encryption needs for information security.

[0054] Through the control module, the LFSR module is controlled to generate the data required by the initial conditions of the hyperchaotic system module. After stable operation, the encryption factor will be generated for output, and the hyperchaotic system can be interfered with again through the control module.

[0055] In some embodiments, the circuit structure of the LFSR module is based on a mathematical characteristic polynomial, including:

[0056] G(X)=g m X m +g m-1 X m-1 +g m-2 X m-2 +…+g2X2+g10X+g0;

[0057] Among them, g m g0 is the coefficient, X is the variable, and m is the highest order index of the polynomial.

[0058] In some embodiments, the LFSR module is 32 bits and each new value generated is a state.

[0059] In some embodiments, the high-order 16-bit data output by the LFSR module is used as the initial condition value and interference value of the hyperchaotic system module.

[0060] Specifically, the implementation of LFSR in hardware is relatively simple and efficient. It only requires a small number of logic gates and triggers to achieve long-period pseudo-random sequence generation. This feature makes LFSR a very useful technology in digital circuit design. However, due to its relative simplicity, it is more predictable and encrypted information can be easily cracked.

[0061] In practical applications, the realization of chaotic systems is limited by computational precision. Limited precision may lead to the degradation of chaotic behavior, making the system state predictable after long simulations.

[0062] Therefore, in order to avoid these two shortcomings as much as possible, we can use the sensitivity of the initial conditions of the chaotic system and its sensitivity to external interference. We use LFSR to generate the initial condition value and decide whether to interfere with the system according to the control module to enhance the corresponding randomness.

[0063] In the present invention, 32 bits are selected for LFSR. If each new value generated by LFSR is a state, then there are 2 32 -1 state. If a state lasts for 1 second, it will take about 136.71 years for a repeated state to appear, further reducing the possibility of prediction.

[0064] Among them, the high 16 bits of data are output as the initial condition value and interference value of the hyperchaotic system.

[0065] In some embodiments, the hyperchaotic system module is implemented using a modified Euler algorithm.

[0066] Specifically, the improved Euler algorithm is selected in the present invention to build the digital circuit of the hyperchaotic system, because in secure communication, there is a contradiction between the realization accuracy and confidentiality of the chaotic system.

[0067] High-precision implementation may increase the complexity and cost of the system, while low-precision implementation may reduce the confidentiality of the system. In this way, a relatively satisfactory accuracy value can be obtained without increasing the complexity of the system as much as possible.

[0068] Chaotic system is a completely deterministic set of three-order autonomous ordinary differential equations proposed by American meteorologist Lorenz when studying atmospheric motion by simplifying the convection model and retaining only three variables. It is called the Lorenz system, and its equation form is as follows:

[0069]

[0070] Among them, the three parameters are: a is the Prandtl number, c is the Rayleigh number, and b is the direction ratio.

[0071] Adding a nonlinear equation w = -yz + rw to the Lorenz system, we can get a hyperchaotic system based on the Lorenz system, which is expressed as follows:

[0072]

[0073] The new parameter r introduced is the driving quantity, which determines the change of w.

[0074] In summary, the design of hyperchaotic system based on Lorenz system can be further explained as four parts: A controls the different characteristics of the system, B controls the dissipation rate of the system, C affects the nonlinear behavior of the system, and D represents the external driving term. These correspond to the four expressions of hyperchaotic system theory.

[0075] A:X=a(yx)+w B:y=cx-y-xz C:z=xy-bz B:w=-yz+rw

[0076] In some embodiments, the control module controls whether to select the random data generated by the LFSR module as the interference value of the hyperchaotic system module through the input signal in_o.

[0077] In some embodiments, the control module also controls whether to use external data as the initial condition value, interference value and encryption key of the hyperchaotic system module through input signals d and en;

[0078] If external data is not selected as the encryption key, the encryption key automatically generated by the system will be used and output.

[0079] Specifically, the LFSR is controlled to generate random 16-bit data as the initial condition value and interference value of the hyperchaotic system, and the output is used as the encryption key. In_o is used to control whether the data is selected as the interference value of the hyperchaotic system.

[0080] And the input d and en can be used to control whether to use external data as the initial condition value and interference value of the hyperchaotic system, that is, the encryption key, to further improve the flexibility of the system.

[0081] In some embodiments, the system is designed using FPGA technology, which effectively combines hardware design with algorithms and has the general advantages of FPGA platform technology, thereby making the development and design of the encryption system very convenient and conducive to subsequent updates and iterations.

[0082] In some other embodiments, an encryption method based on LFSR and hyperchaotic system is provided, wherein the encryption system based on LFSR and hyperchaotic system according to any one of the above items comprises the following steps:

[0083] Step S01, controlling the LFSR module to generate a pseudo-random sequence through the control module;

[0084] Step S02: using the high 16-bit data output by the LFSR module as the initial condition of the hyperchaotic system module;

[0085] Step S03, the hyperchaotic system module operates according to the initial conditions and generates encryption factors;

[0086] Step S04: as required, the control module determines whether to perform external interference on the hyperchaotic system module;

[0087] Step S05: output the encryption factor and the corresponding encryption key.

[0088] In some embodiments, it also includes receiving an external input signal through a control module to determine whether to use external data as the initial conditions, interference values ​​and encryption keys of the hyperchaotic system module.

[0089] like Figures 5 to 14 As shown in the figure, according to the simulation results, not controlling in_o is to interfere with the hyperchaotic system, which has good hyperchaotic properties;

[0090] Controlling in_o is to interfere with the hyperchaotic system. The duration and frequency of the interference have a great impact on the final result.

[0091] Compared with the traditional method, the present invention can greatly improve the security required for information encryption, and at the same time, the interference data of the external input hyperchaotic system can be regarded as a part of the encryption key, thereby improving the flexibility of the overall system.

[0092] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit it. Although the present invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the aforementioned embodiments, or replace some or all of the technical features therein by equivalents. These modifications or replacements do not deviate the essence of the corresponding technical solutions from the scope of the technical solutions of the embodiments of the present invention, and they should all be included in the scope of the claims and specification of the present invention.

Claims

1. An encryption system based on LFSR and hyperchaotic system, characterized in that: include: LFSR module, control module and hyperchaotic system module; Among them, the LFSR module is used to generate a pseudo-random sequence as the initial condition and possible interference value of the hyperchaotic system module; The control module is used to control the output of the LFSR module and decide whether to perform external interference on the hyperchaotic system module; The hyperchaotic system module receives the initial conditions generated by the LFSR module, runs to generate encryption factors, and can receive external interference according to the instructions of the control module.

2. The encryption system based on LFSR and hyperchaotic system according to claim 1, characterized in that: The circuit structure of the LFSR module is based on the mathematical characteristic polynomial, including: G(X)=g m X m +g m-1 X m-1 +g m-2 X m-2 +…+g2X2+g10X+g0; Where gm to g0 are coefficients, X is the variable, and m is the highest-order exponent of the polynomial.

3. The encryption system based on LFSR and hyperchaotic system according to claim 1, characterized in that: The LFSR module is 32 bits, and each new value generated is a state.

4. The encryption system based on LFSR and hyperchaotic system according to claim 3, characterized in that: The high-order 16-bit data output by the LFSR module is used as the initial condition value and interference value of the hyperchaotic system module.

5. The encryption system based on LFSR and hyperchaotic system according to claim 4, characterized in that: The hyperchaotic system module is implemented using a modified Euler algorithm.

6. The encryption system based on LFSR and hyperchaotic system according to claim 1, characterized in that: The control module controls whether to select the random data generated by the LFSR module as the interference value of the hyperchaotic system module through the input signal in_o.

7. The encryption system based on LFSR and hyperchaotic system according to claim 6, characterized in that: The control module also controls whether to use external data as the initial condition value, interference value and encryption key of the hyperchaotic system module through input signals d and en; If external data is not selected as the encryption key, the encryption key automatically generated by the system will be used and output.

8. The encryption method based on LFSR and hyperchaotic system is characterized by: The encryption system based on LFSR and hyperchaotic system according to any one of claims 1 to 7 comprises the following steps: Control the LFSR module to generate a pseudo-random sequence through the control module; The high 16-bit data output by the LFSR module is used as the initial condition of the hyperchaotic system module; The hyperchaotic system module operates according to the initial conditions and generates encryption factors; According to the needs, the control module decides whether to conduct external interference to the hyperchaotic system module; Output the encryption factor and the corresponding encryption key.

9. The encryption method based on LFSR and hyperchaotic system according to claim 8, characterized in that: The method also includes receiving external input signals through a control module and determining whether to use external data as initial conditions, interference values ​​and encryption keys of a hyperchaotic system module.

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