CN112732776B - Secure approximate pattern matching method and system and electronic equipment - Google Patents

Abstract

The present disclosure provides a secure approximate pattern matching method, system and electronic device, there are a first terminal holding a pattern character string, a length of the text character string and a threshold value and a second terminal holding the text character string, the length of the pattern character string and the threshold value, the first terminal and the second terminal execute a secure approximate pattern matching algorithm, if a hamming distance between a certain sub-character string of the text character string and the pattern character string is less than the threshold value, the first terminal outputs a position of the sub-character string in the text character string; according to the method and the device, the user with the mode information can obtain the position of the mode in the database, the database can not know the mode information of the user through the disappearing transmission algorithm and the Boolean type threshold privacy set intersection algorithm, the user can not know other data information in the database, and the mode matching is carried out while the safety of the data is guaranteed.

Description

A secure approximate pattern matching method, system and electronic device

technical field

The present disclosure relates to the technical field of pattern matching, and in particular, to a method, system and electronic device for secure approximate pattern matching.

Background technique

The statements in this section merely provide background related to the present disclosure and do not necessarily constitute prior art.

Approximate pattern matching is widely used. For example, in the face recognition system, when the light, position or expression is different, the feature data of the user's facial image extracted by the system is also different. When the feature templates in the database are matched, the identity information corresponding to the facial image needs to be judged according to the similarity between the two, rather than whether the two are the same.

However, the inventor found that the user's facial data and the feature templates in the database belong to private data, and both parties usually do not want to disclose their private data to avoid revealing their private information.

SUMMARY OF THE INVENTION

In order to solve the deficiencies of the prior art, the present disclosure provides a method, system and electronic device for secure approximate pattern matching. Users who hold pattern information can obtain the location where their pattern appears in the database. In the privacy set intersection algorithm, the database side cannot know the user's pattern information, and the user cannot know other data information in the database, which ensures the security of their respective data while performing pattern matching.

In order to achieve the above object, the present disclosure adopts the following technical solutions:

A first aspect of the present disclosure provides a secure approximate pattern matching method.

A secure approximate pattern matching method applied to a first terminal holding a pattern string, the length of a text string and a threshold, comprising the following steps:

The first terminal executes a secure approximate pattern matching algorithm with the second terminal that holds the text string, the length of the pattern string and the threshold. If the Hamming distance between a substring of the text string and the pattern string is less than the threshold, the first A terminal outputs the position of this substring within the text string.

A second aspect of the present disclosure provides an electronic device.

An electronic device, comprising a first terminal holding a pattern string, the length of the text string and a threshold, the first terminal communicating with a second terminal holding the text string, the length of the pattern string and the threshold;

The first terminal and the second terminal execute a secure approximate pattern matching algorithm. If the Hamming distance between a certain substring of the text string and the pattern string is less than the threshold, the first terminal outputs the substring in the text string. s position.

A third aspect of the present disclosure provides a secure approximate pattern matching method.

A secure approximate pattern matching method, applied to a second terminal holding a text string, a pattern string length and a threshold, comprising the following steps:

The second terminal performs a secure approximate pattern matching algorithm with the first terminal holding the pattern string, the length of the text string and the threshold, if the Hamming distance between a certain substring of the text string and the pattern string is less than the threshold, Causes the first terminal to output the position of this substring within the text string.

A fourth aspect of the present disclosure provides an electronic device.

An electronic device, comprising a second terminal holding a text string, a pattern string length and a threshold, the second terminal communicating with a first terminal holding the pattern string, the length of the text string and the threshold;

The first terminal and the second terminal execute a secure approximate pattern matching algorithm. If the Hamming distance between a certain substring of the text string and the pattern string is less than the threshold, the first terminal outputs the text string of the substring. in the location.

A fifth aspect of the present disclosure provides a secure approximate pattern matching method.

A method for secure approximate pattern matching, having a first terminal holding a pattern string, the length of the text string and a threshold, and a second terminal holding the text string, the length of the pattern string and the threshold, comprising the following steps:

The first terminal and the second terminal execute a secure approximate pattern matching algorithm. If the Hamming distance between a certain substring of the text string and the pattern string is less than the threshold, the first terminal outputs the substring in the text string. s position.

A sixth aspect of the present disclosure provides a secure approximate pattern matching system.

A secure approximate pattern matching system, comprising a first terminal holding a pattern string, the length of the text string and a threshold, and a second terminal holding the text string, the length of the pattern string and the threshold, the first terminal and the second terminal Terminal communication:

The first terminal and the second terminal execute a secure approximate pattern matching algorithm. If the Hamming distance between a certain substring of the text string and the pattern string is less than the threshold, the first terminal outputs the substring in the text string. s position.

Compared with the prior art, the beneficial effects of the present disclosure are:

1. With the method, electronic device or system described in the present disclosure, the user who holds the pattern information can obtain the position where the pattern appears in the database, and the database party cannot know the location of the pattern in the database through the blind transmission algorithm and the Boolean type threshold privacy set intersection algorithm. The user's pattern information, the user cannot know other data information in the database, and ensures the security of their respective data while performing pattern matching.

2. The method, electronic device or system described in the present disclosure enables the participant who holds the pattern information to obtain the position where the pattern appears in the text, but the participant who holds the text cannot obtain any relevant information about the pattern. Other relevant information about the text is not available to parties with patterns.

Description of drawings

The accompanying drawings that constitute a part of the present disclosure are used to provide further understanding of the present disclosure, and the exemplary embodiments of the present disclosure and their descriptions are used to explain the present disclosure and do not constitute an improper limitation of the present disclosure.

FIG. 1 is a schematic flowchart of the secure approximate pattern matching method provided in Embodiment 1 of the present disclosure.

Detailed ways

The present disclosure will be further described below with reference to the accompanying drawings and embodiments.

It should be noted that the following detailed description is exemplary and intended to provide further explanation of the present disclosure. Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this disclosure belongs.

It should be noted that the terminology used herein is for the purpose of describing specific embodiments only, and is not intended to limit the exemplary embodiments according to the present disclosure. As used herein, unless the context clearly dictates otherwise, the singular is intended to include the plural as well, furthermore, it is to be understood that when the terms "comprising" and/or "including" are used in this specification, it indicates that There are features, steps, operations, devices, components and/or combinations thereof.

The embodiments of this disclosure and features of the embodiments may be combined with each other without conflict.

Example 1:

As shown in FIG. 1 , Embodiment 1 of the present disclosure provides a secure approximate pattern matching method, which is applied to a first terminal (ie P ₁ );

The input of the participant P ₀ (ie the second terminal) is the text string t∈{0,1} ⁿ , the length m of the pattern string and the threshold τ, and the input of the participant P ₁ is the pattern string p∈{0, 1} ^m , the length n of the text string and the threshold τ;

After the execution of the safe approximate pattern matching algorithm, if the Hamming distance between the ith substring of t and p is less than τ, then P ₁ outputs position i, which is formally described as follows:

Input: The input of P ₀ is (t, m, τ), and the input of P ₁ is (p, n, τ).

Output: P ₁ outputs i if the Hamming distance between the ith substring of t and p is less than τ.

Initialization: Set the security parameter as λ, set the global parameter p, p is a prime number, and its binary length |p|>λ.

Safe approximate pattern matching algorithm, as follows:

其中

P₀根据文本字符串t的每一个长度为m的子字符串选择相应的随机数，得到文本集合

其中i＝1,…,n-m+1；(1) P ₀ randomly selects m pairs of random numbers, which are

in

P ₀ selects the corresponding random number according to each substring of length m of the text string t, and obtains the text set

where i=1,...,n-m+1;

P₁的输入为p_j，算法执行结束后，P₁得到模式集合

( ₂ ) For each j _{= 1} , .

The input of P ₁ is p _j , after the execution of the algorithm, P ₁ gets the pattern set

(3) For each _{i = 1} , _. , the input of P ₁ is (S,m,m-τ). After the algorithm is executed, P ₁ obtains the output set b _i ∈{0,1} ^n-m+1 .

(4) If bi = 1, P ₁ outputs _i .

Boolean type threshold privacy set intersection algorithm, as follows:

In the Boolean threshold privacy set intersection algorithm, C and S are sets, |C| and |S| are the lengths of sets C and S, respectively, t is the threshold, and the input of the participant P ₀ is (C, |S| ,t), the input of the participant P ₁ is (S,|C|,t). After the algorithm runs, if |C∩S|≥t, P ₁ outputs 1, otherwise P ₁ outputs 0. The specific description is as follows:

Input: The input of P ₀ is (C, |S|, T), and the input of P ₁ is (S, |C|, t).

Output: If |C∩S|≥t, P ₁ outputs 1, otherwise P ₁ outputs 0.

Initialization: Set the security parameter to λ and set the global parameter p. p is a prime number whose binary length |p|>λ.

1) P ₀ publishes the public additive homomorphic encryption public key pk ₁ , then P ₀ and P ₁ execute the private set intersection cardinality algorithm, and P ₁ obtains Enc(pk ₁ ,|C∩S|).

2) P ₁ selects a random number r∈{0,…,p-1}, and performs additive homomorphic calculation to obtain Enc(pk ₁ ,|C∩S|+r)=Enc(pk ₁ ,|C∩S|) ·Enc(pk ₁ ,r);

P ₁ selects random numbers r′∈{0,…,p-1} and R∈{0,…,p-1}, and prepares a root as r+t,r+t+1,…,r+min( |C|, |S|) polynomial p(·), then calculate polynomial p′(·)=r′·p(·)+R, the coefficients of polynomial p′(·) are a ₀ , a ₁ ,… ,a _{min(|C|,|S|+1} ;

P ₁ encrypts the coefficients of the polynomial p'(·) with the additive homomorphic encryption public key pk ₂ , and the encrypted coefficients are

Enc(pk ₂ ,a ₀ ),Enc(pk ₂ ,a ₁ ),…,Enc(pk ₂ ,a _{min(|C|,|S|+1} );

P ₁ sends the encryption coefficient of the polynomial p'(·) and Enc(pk ₁ , |C∩S|+r) to P ₀ .

3) P ₀ decrypts the received ciphertext to get |C∩S|+r, then use the point |C∩S|+r to calculate the polynomial p′(·) at a loss, and record the result as Enc(pk ₂ ,R '),available:

P ₀ selects a random number r"∈{0,...,p-1}, and performs additive homomorphic calculation to obtain Enc(pk ₁ ,R′+r")=Enc(pk ₁ ,R′)·Enc(pk ₁ , r" ₎ , and then send it to P1 to request its decryption.

4) P ₁ decrypts Enc(pk ₁ , R'+r") and sends the result R'+r" to P ₀ , and P ₀ obtains R' through calculation.

5) P ₀ and P ₁ execute the privacy equality test algorithm, where P ₀ inputs R′, P ₁ inputs R, and after the algorithm is executed, P ₁ outputs 0 or 1.

In this embodiment, the dazed transmission algorithm is specifically as follows:

算法中，发送方S输入2个消息(x₀,x₁)，接收方R输入一个选择信息σ∈{0,1}，双方执行算法后，R输出x_σ；除此之外，不泄露任何额外信息。The oblivious transfer (OT) algorithm is a two-party algorithm. The two parties are the sender S and the receiver R respectively.

In the algorithm, the sender S inputs 2 messages (x ₀ , x ₁ ), the receiver R inputs a selection information σ∈{0,1}, after both parties execute the algorithm, R outputs x _σ ; in addition, no leakage any additional information.

In this embodiment, the privacy equality test is as follows:

The private equality test (PEQT) algorithm is a two-party algorithm, and the two parties are the sender S and the receiver R respectively. The input of the sender S is x ₀ , and the input of the receiver R is x ₁ . After both parties execute the algorithm, if x ₀ =x ₁ , R outputs 1, otherwise R outputs 0. Other than that, no additional information is disclosed.

In this embodiment, the encryption privacy set intersection cardinality is as follows:

The encrypted private set intersection-cardinality (ePSI-CA) algorithm is a two-party algorithm, and the two parties are P ₀ and P ₁ respectively. C and S are sets, |C| and |S| are the lengths of sets C and S, respectively, (pk ₁ , sk ₁ ) and (pk ₂ , sk ₂ ) are the additive homomorphic encryption keys of P ₀ and P ₁ right. The input of P ₀ is (C,|S|,pk ₁ ,sk ₁ ), and the input of P ₁ is (S,|C|,pk ₁ ,pk ₂ ,sk ₂ ), after the two parties execute the agreement, P ₁ outputs encryption The number of subsequent intersection elements Enc(pk ₁ ,|C∩S|).

Example 2:

Embodiment 2 of the present disclosure provides an electronic device, including a first terminal holding a pattern string, the length of the text string and a threshold, the first terminal and a second terminal holding the text string, the length of the pattern string and the threshold terminal communication;

The first terminal and the second terminal execute a secure approximate pattern matching algorithm. If the Hamming distance between a certain substring of the text string and the pattern string is less than the threshold, the first terminal outputs the substring in the text string. s position.

The specific working method of the device is the same as the method provided in Embodiment 1, and will not be repeated here.

Example 3:

Embodiment 3 of the present disclosure provides a secure approximate pattern matching method, which is applied to a second terminal holding a text string, a pattern string length, and a threshold, including the following steps:

The second terminal performs a secure approximate pattern matching algorithm with the first terminal holding the pattern string, the length of the text string and the threshold, if the Hamming distance between a certain substring of the text string and the pattern string is less than the threshold, Causes the first terminal to output the position of this substring within the text string.

The detailed method is the same as that provided in Embodiment 1, and will not be repeated here.

Example 4:

Embodiment 4 of the present disclosure provides an electronic device, including a second terminal that holds a text string, the length of the pattern string, and a threshold, the second terminal and a first terminal that holds the pattern string, the length of the text string, and the threshold terminal communication;

The first terminal and the second terminal execute a secure approximate pattern matching algorithm. If the Hamming distance between a certain substring of the text string and the pattern string is less than the threshold, the first terminal outputs the text string of the substring. in the location.

The specific working method of the device is the same as the method provided in Embodiment 1, and will not be repeated here.

Example 5:

Embodiment 5 of the present disclosure provides a secure approximate pattern matching method. There are a first terminal holding a pattern string, the length of the text string, and a threshold, and a second terminal holding the text string, the length of the pattern string, and a threshold. , including the following steps:

The first terminal and the second terminal execute a secure approximate pattern matching algorithm. If the Hamming distance between a certain substring of the text string and the pattern string is less than the threshold, the first terminal outputs the substring in the text string. s position.

The detailed method is the same as that provided in Embodiment 1, and will not be repeated here.

Example 6:

Embodiment 6 of the present disclosure provides a secure approximate pattern matching system, including a first terminal holding a pattern string, the length of the text string, and a threshold, and a second terminal holding the text string, the length of the pattern string, and a threshold , the first terminal communicates with the second terminal:

The first terminal and the second terminal execute a secure approximate pattern matching algorithm. If the Hamming distance between a certain substring of the text string and the pattern string is less than the threshold, the first terminal outputs the substring in the text string. s position.

The working method of the system is the same as the method provided in Embodiment 1, and details are not repeated here.

As will be appreciated by one skilled in the art, embodiments of the present disclosure may be provided as a method, system, or computer program product. Accordingly, the present disclosure may take the form of a hardware embodiment, a software embodiment, or an embodiment combining software and hardware aspects. Furthermore, the present disclosure may take the form of a computer program product embodied on one or more computer-usable storage media having computer-usable program code embodied therein, including but not limited to disk storage, optical storage, and the like.

The present disclosure is described with reference to flowchart illustrations and/or block diagrams of methods, apparatus (systems), and computer program products according to embodiments of the disclosure. It will be understood that each flow and/or block in the flowchart illustrations and/or block diagrams, and combinations of flows and/or blocks in the flowchart illustrations and/or block diagrams, can be implemented by computer program instructions. These computer program instructions may be provided to the processor of a general purpose computer, special purpose computer, embedded processor or other programmable data processing device to produce a machine such that the instructions executed by the processor of the computer or other programmable data processing device produce Means for implementing the functions specified in a flow or flow of a flowchart and/or a block or blocks of a block diagram.

These computer program instructions may also be stored in a computer-readable memory capable of directing a computer or other programmable data processing apparatus to function in a particular manner, such that the instructions stored in the computer-readable memory result in an article of manufacture comprising instruction means, the instructions The apparatus implements the functions specified in the flow or flow of the flowcharts and/or the block or blocks of the block diagrams.

These computer program instructions can also be loaded on a computer or other programmable data processing device to cause a series of operational steps to be performed on the computer or other programmable device to produce a computer-implemented process such that The instructions provide steps for implementing the functions specified in the flow or blocks of the flowcharts and/or the block or blocks of the block diagrams.

Those of ordinary skill in the art can understand that all or part of the processes in the methods of the above embodiments can be implemented by instructing relevant hardware through a computer program, and the program can be stored in a computer-readable storage medium. During execution, the processes of the embodiments of the above-mentioned methods may be included. The storage medium may be a magnetic disk, an optical disk, a read-only memory (Read-Only Memory, ROM), or a random access memory (Random Access Memory, RAM) or the like.

The above descriptions are only preferred embodiments of the present disclosure, and are not intended to limit the present disclosure. For those skilled in the art, the present disclosure may have various modifications and changes. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present disclosure shall be included within the protection scope of the present disclosure.

Claims (6)

1. a safe approximate pattern matching method, is characterized in that: be applied to the first terminal that holds the length of pattern string, text string and threshold, comprises the following steps: The first terminal executes a secure approximate pattern matching algorithm with the second terminal that holds the text string, the length of the pattern string and the threshold. If the Hamming distance between a substring of the text string and the pattern string is less than the threshold, the first A terminal outputs the position of the substring within the text string; Safe approximate pattern matching algorithms, including: The second terminal randomly selects m pairs of random numbers, which are

The second terminal selects a corresponding random number according to each substring of length m of the text string t, and obtains a text set

where i=1,...,n-m+1; For each j=1,...,m, the first terminal and the second terminal perform a 2-to-1 blind transmission algorithm, and the input of the second terminal is

The input of the first terminal is p _j . After the algorithm is executed, the first terminal obtains the pattern set

For each _i =1, . The input of the terminal is S,m,m-τ, after the algorithm is executed, the first terminal obtains the output set b _i ∈{0,1} ^n-m+1 ; If b _i =1, the first terminal outputs i; Boolean threshold privacy set intersection algorithm, including: The second terminal publishes the public additive homomorphic encryption public key pk ₁ , then the first terminal and the second terminal execute the private set intersection radix algorithm, and the first terminal obtains Enc(pk ₁ ,|C∩S|); The first terminal selects a random number r∈{0,...,p-1} and performs additive homomorphic calculation to obtain Enc(pk ₁ ,|C∩S|+r)=Enc(pk ₁ ,|C∩S|)· Enc(pk ₁ ,r); The first terminal selects random numbers r′∈{0,…,p-1} and R∈{0,…,p-1}, and prepares a root of r+t,r+t+1,…,r+min (|C|,|S|) polynomial p(·), then calculate polynomial p′(·)=r′·p(·)+R, the coefficients of polynomial p′(·) are a ₀ ,a ₁ , …,a _{min(|C|,|S|) +1} ; The first terminal uses the additive homomorphic encryption public key pk ₂ to encrypt the coefficients of the polynomial p'(·), and the encrypted coefficients are obtained as Enc(pk ₂ , a ₀ ), Enc(pk ₂ , a ₁ ), ... ,Enc(pk ₂ ,a _{min(|C|,|S|)+1} ); The first terminal sends the encryption coefficient of the polynomial p'(·) and Enc(pk ₁ , |C∩S|+r) to the second terminal; The second terminal decrypts the received ciphertext to obtain |C∩S|+r, then uses the point |C∩S|+r to calculate the polynomial p′(·) at a loss, and denote the obtained result as Enc(pk ₂ ,R′ ),get:

The second terminal selects a random number r"∈{0,...,p-1} and performs additive homomorphic calculation to obtain Enc(pk ₁ ,R'+r")=Enc(pk ₁ ,R')·Enc(pk ₁ ,r"), and then send it to the first terminal to request its decryption; The first terminal decrypts Enc(pk ₁ , R'+r") and sends the result R'+r" to the second terminal, and the second terminal obtains R' through calculation; The first terminal and the second terminal execute the privacy equality test algorithm, wherein the second terminal inputs R', the first terminal inputs R, and after the algorithm execution ends, the first terminal outputs 0 or 1; where m is the length of the pattern string; n is the length of the text string; τ is the threshold given in the secure approximate pattern matching algorithm; C is the set held by the first terminal; S is the set held by the second terminal; let The security parameter is λ, and the global parameter p is set, where p is a prime number, and its binary length |p|>λ; |C| is the number of elements in the set C; |S| is the number of elements in the set S; t is a Boolean type Thresholds given in the privacy set intersection algorithm. 2. An electronic device, characterized in that: comprising a first terminal holding a pattern string, the length of a text string and a threshold, the first terminal and a second terminal holding a text string, the length of the pattern string and the threshold communication; The first terminal and the second terminal execute a secure approximate pattern matching algorithm. If the Hamming distance between a certain substring of the text string and the pattern string is less than the threshold, the first terminal outputs the substring in the text string. s position; Safe approximate pattern matching algorithms, including: The second terminal randomly selects m pairs of random numbers, which are

The second terminal selects a corresponding random number according to each substring of length m of the text string t, and obtains a text set

where i=1,...,n-m+1; For each j=1,...,m, the first terminal and the second terminal perform a 2-to-1 blind transmission algorithm, and the input of the second terminal is

The input of the first terminal is p _j . After the algorithm is executed, the first terminal obtains the pattern set

For each _i =1, . The input of the terminal is S,m,m-τ, after the algorithm is executed, the first terminal obtains the output set b _i ∈{0,1} ^n-m+1 ; If b _i =1, the first terminal outputs i; Boolean threshold privacy set intersection algorithm, including: The second terminal publishes the public additive homomorphic encryption public key pk ₁ , then the first terminal and the second terminal execute the private set intersection radix algorithm, and the first terminal obtains Enc(pk ₁ ,|C∩S|); The first terminal selects a random number r∈{0,...,p-1} and performs additive homomorphic calculation to obtain Enc(pk ₁ ,|C∩S|+r)=Enc(pk ₁ ,|C∩S|)· Enc(pk ₁ ,r); The first terminal selects random numbers r′∈{0,…,p-1} and R∈{0,…,p-1}, and prepares a root of r+t,r+t+1,…,r+min (|C|,|S|) polynomial p(·), then calculate polynomial p′(·)=r′·p(·)+R, the coefficients of polynomial p′(·) are a ₀ , a ₁ , …,a _{min(|C|,|S|)+1} ; The first terminal uses the additive homomorphic encryption public key pk ₂ to encrypt the coefficients of the polynomial p'(·), and the encrypted coefficients are obtained as Enc(pk ₂ , a ₀ ), Enc(pk ₂ , a ₁ ), ... ,Enc(pk ₂ ,a _{min(|C|,|S|)+1} ); The first terminal sends the encryption coefficient of the polynomial p'(·) and Enc(pk ₁ , |C∩S|+r) to the second terminal; The second terminal decrypts the received ciphertext to obtain |C∩S|+r, then uses the point |C∩S|+r to calculate the polynomial p′(·) at a loss, and denote the obtained result as Enc(pk ₂ ,R′ ),get:

The second terminal selects a random number r"∈{0,...,p-1} and performs additive homomorphic calculation to obtain Enc(pk ₁ ,R'+r")=Enc(pk ₁ ,R')·Enc(pk ₁ ,r"), and then send it to the first terminal to request its decryption; The first terminal decrypts Enc(pk ₁ , R'+r") and sends the result R'+r" to the second terminal, and the second terminal obtains R' through calculation; The first terminal and the second terminal execute the privacy equality test algorithm, wherein the second terminal inputs R', the first terminal inputs R, and after the algorithm execution ends, the first terminal outputs 0 or 1; where m is the length of the pattern string; n is the length of the text string; τ is the threshold given in the secure approximate pattern matching algorithm; C is the set held by the first terminal; S is the set held by the second terminal; let The security parameter is λ, and the global parameter p is set, where p is a prime number, and its binary length |p|>λ; |C| is the number of elements in the set C; |S| is the number of elements in the set S; t is a Boolean type Thresholds given in the privacy set intersection algorithm. 3. A safe approximate pattern matching method, characterized in that: being applied to a second terminal holding a text string, a pattern string length and a threshold, comprising the following steps: The second terminal performs a secure approximate pattern matching algorithm with the first terminal holding the pattern string, the length of the text string and the threshold, if the Hamming distance between a certain substring of the text string and the pattern string is less than the threshold, Causes the first terminal to output the position of the substring in the text string; Safe approximate pattern matching algorithms, including: The second terminal randomly selects m pairs of random numbers, which are

The second terminal selects a corresponding random number according to each substring of length m of the text string t, and obtains a text set

where i=1,...,n-m+1; For each j=1,...,m, the first terminal and the second terminal perform a 2-to-1 blind transmission algorithm, and the input of the second terminal is

The input of the first terminal is p _j . After the algorithm is executed, the first terminal obtains the pattern set

For each _i =1, . The input of the terminal is S,m,m-τ, after the algorithm is executed, the first terminal obtains the output set b _i ∈{0,1} ^n-m+1 ; If b _i =1, the first terminal outputs i; Boolean threshold privacy set intersection algorithm, including: The second terminal publishes the public additive homomorphic encryption public key pk ₁ , then the first terminal and the second terminal execute the private set intersection radix algorithm, and the first terminal obtains Enc(pk ₁ ,|C∩S|); The first terminal selects a random number r∈{0,...,p-1} and performs additive homomorphic calculation to obtain Enc(pk ₁ ,|C∩S|+r)=Enc(pk ₁ ,|C∩S|)· Enc(pk ₁ ,r); The first terminal selects random numbers r′∈{0,…,p-1} and R∈{0,…,p-1}, and prepares a root of r+t,r+t+1,…,r+min (|C|,|S|) polynomial p(·), then calculate polynomial p′(·)=r′·p(·)+R, the coefficients of polynomial p′(·) are a ₀ , a ₁ , …,a _{min(|C|,|S|)+1} ; The first terminal uses the additive homomorphic encryption public key pk ₂ to encrypt the coefficients of the polynomial p'(·), and the encrypted coefficients are obtained as Enc(pk ₂ , a ₀ ), Enc(pk ₂ , a ₁ ), ... ,Enc(pk ₂ ,a _{min(|C|,|S|)+1} ); The first terminal sends the encryption coefficient of the polynomial p'(·) and Enc(pk ₁ , |C∩S|+r) to the second terminal; The second terminal decrypts the received ciphertext to obtain |C∩S|+r, then uses the point |C∩S|+r to calculate the polynomial p′(·) at a loss, and denote the obtained result as Enc(pk ₂ ,R′ ),get:

The second terminal selects a random number r"∈{0,...,p-1} and performs additive homomorphic calculation to obtain Enc(pk ₁ ,R'+r")=Enc(pk ₁ ,R')·Enc(pk ₁ ,r"), and then send it to the first terminal to request its decryption; The first terminal decrypts Enc(pk ₁ , R'+r") and sends the result R'+r" to the second terminal, and the second terminal obtains R' through calculation; The first terminal and the second terminal execute the privacy equality test algorithm, wherein the second terminal inputs R', the first terminal inputs R, and after the algorithm execution ends, the first terminal outputs 0 or 1; where m is the length of the pattern string; n is the length of the text string; τ is the threshold given in the secure approximate pattern matching algorithm; C is the set held by the first terminal; S is the set held by the second terminal; let The security parameter is λ, and the global parameter p is set, where p is a prime number, and its binary length |p|>λ; |C| is the number of elements in the set C; |S| is the number of elements in the set S; t is a Boolean type Thresholds given in the privacy set intersection algorithm. 4. An electronic device, characterized in that: comprising a second terminal holding a text string, the length of the pattern string and a threshold, the second terminal and the first terminal holding the pattern string, the length of the text string and the threshold communication; The first terminal and the second terminal execute a secure approximate pattern matching algorithm. If the Hamming distance between a certain substring of the text string and the pattern string is less than the threshold, the first terminal outputs the text string of the substring. position in; Safe approximate pattern matching algorithms, including: The second terminal randomly selects m pairs of random numbers, which are

The second terminal selects a corresponding random number according to each substring of length m of the text string t, and obtains a text set

where i=1,...,n-m+1; For each j=1,...,m, the first terminal and the second terminal perform a 2-to-1 blind transmission algorithm, and the input of the second terminal is

The input of the first terminal is p _j . After the algorithm is executed, the first terminal obtains the pattern set

For each _i =1, . The input of the terminal is S,m,m-τ, after the algorithm is executed, the first terminal obtains the output set b _i ∈{0,1} ^n-m+1 ; If b _i =1, the first terminal outputs i; Boolean threshold privacy set intersection algorithm, including: The second terminal publishes the public additive homomorphic encryption public key pk ₁ , then the first terminal and the second terminal execute the private set intersection radix algorithm, and the first terminal obtains Enc(pk ₁ ,|C∩S|); The first terminal selects a random number r∈{0,...,p-1} and performs additive homomorphic calculation to obtain Enc(pk ₁ ,|C∩S|+r)=Enc(pk ₁ ,|C∩S|)· Enc(pk ₁ ,r); The first terminal selects random numbers r′∈{0,…,p-1} and R∈{0,…,p-1}, and prepares a root of r+t,r+t+1,…,r+min (|C|,|S|) polynomial p(·), then calculate polynomial p′(·)=r′·p(·)+R, the coefficients of polynomial p′(·) are a ₀ , a ₁ , …,a _{min(|C|,|S|) +1} ; The first terminal uses the additive homomorphic encryption public key pk ₂ to encrypt the coefficients of the polynomial p'(·), and the encrypted coefficients are obtained as Enc(pk ₂ , a ₀ ), Enc(pk ₂ , a ₁ ), ... ,Enc(pk ₂ ,a _{min(|C|,|S|)+1} ); The first terminal sends the encryption coefficient of the polynomial p'(·) and Enc(pk ₁ , |C∩S|+r) to the second terminal; The second terminal decrypts the received ciphertext to obtain |C∩S|+r, then uses the point |C∩S|+r to calculate the polynomial p′(·) at a loss, and denote the obtained result as Enc(pk ₂ ,R′ ),get:

The second terminal selects a random number r"∈{0,...,p-1} and performs additive homomorphic calculation to obtain Enc(pk ₁ ,R'+r")=Enc(pk ₁ ,R')·Enc(pk ₁ ,r"), and then send it to the first terminal to request its decryption; The first terminal decrypts Enc(pk ₁ , R'+r") and sends the result R'+r" to the second terminal, and the second terminal obtains R' through calculation; The first terminal and the second terminal execute the privacy equality test algorithm, wherein the second terminal inputs R', the first terminal inputs R, and after the algorithm execution ends, the first terminal outputs 0 or 1; where m is the length of the pattern string; n is the length of the text string; τ is the threshold given in the secure approximate pattern matching algorithm; C is the set held by the first terminal; S is the set held by the second terminal; let The security parameter is λ, and the global parameter p is set, where p is a prime number, and its binary length |p|>λ; |C| is the number of elements in the set C; |S| is the number of elements in the set S; t is a Boolean type Thresholds given in the privacy set intersection algorithm. 5. A method for safe approximate pattern matching, characterized in that: there is a first terminal holding a pattern string, the length of the text string and a threshold and a second terminal holding the text string, the length of the pattern string and the threshold, Include the following steps: The first terminal and the second terminal execute a secure approximate pattern matching algorithm. If the Hamming distance between a certain substring of the text string and the pattern string is less than the threshold, the first terminal outputs the substring in the text string. s position; Safe approximate pattern matching algorithms, including: The second terminal randomly selects m pairs of random numbers, which are

The second terminal selects a corresponding random number according to each substring of length m of the text string t, and obtains a text set

where i=1,...,n-m+1; For each j=1,...,m, the first terminal and the second terminal perform a 2-to-1 blind transmission algorithm, and the input of the second terminal is

The input of the first terminal is p _j . After the algorithm is executed, the first terminal obtains the pattern set

For each _i =1, . The input of the terminal is S,m,m-τ, after the algorithm is executed, the first terminal obtains the output set b _i ∈{0,1} ^n-m+1 ; If b _i =1, the first terminal outputs i; Boolean threshold privacy set intersection algorithm, including: The second terminal publishes the public additive homomorphic encryption public key pk ₁ , then the first terminal and the second terminal execute the private set intersection radix algorithm, and the first terminal obtains Enc(pk ₁ ,|C∩S|); The first terminal selects a random number r∈{0,...,p-1} and performs additive homomorphic calculation to obtain Enc(pk ₁ ,|C∩S|+r)=Enc(pk ₁ ,|C∩S|)· Enc(pk ₁ ,r); The first terminal selects random numbers r′∈{0,…,p-1} and R∈{0,…,p-1}, and prepares a root of r+t,r+t+1,…,r+min (|C|,|S|) polynomial p(·), then calculate polynomial p′(·)=r′·p(·)+R, the coefficients of polynomial p′(·) are a ₀ , a ₁ , …,a _{min(|C|,|S|)+1} ; The first terminal uses the additive homomorphic encryption public key pk ₂ to encrypt the coefficients of the polynomial p'(·), and the encrypted coefficients are obtained as Enc(pk ₂ , a ₀ ), Enc(pk ₂ , a ₁ ), ... ,Enc(pk ₂ ,a _{min(|C|,|S|)+1} ); The first terminal sends the encryption coefficient of the polynomial p'(·) and Enc(pk ₁ , |C∩S|+r) to the second terminal; The second terminal decrypts the received ciphertext to obtain |C∩S|+r, then uses the point |C∩S|+r to calculate the polynomial p′(·) at a loss, and denote the obtained result as Enc(pk ₂ ,R′ ),get:

The second terminal selects a random number r"∈{0,...,p-1} and performs additive homomorphic calculation to obtain Enc(pk ₁ ,R'+r")=Enc(pk ₁ ,R')·Enc(pk ₁ ,r"), and then send it to the first terminal to request its decryption; The first terminal decrypts Enc(pk ₁ , R'+r") and sends the result R'+r" to the second terminal, and the second terminal obtains R' through calculation; The first terminal and the second terminal execute the privacy equality test algorithm, wherein the second terminal inputs R', the first terminal inputs R, and after the algorithm execution ends, the first terminal outputs 0 or 1; where m is the length of the pattern string; n is the length of the text string; τ is the threshold given in the secure approximate pattern matching algorithm; C is the set held by the first terminal; S is the set held by the second terminal; let The security parameter is λ, and the global parameter p is set, where p is a prime number, and its binary length |p|>λ; |C| is the number of elements in the set C; |S| is the number of elements in the set S; t is a Boolean type Thresholds given in the privacy set intersection algorithm. 6. A safe approximate pattern matching system, characterized in that: comprising a first terminal holding a pattern string, the length of the text string and a threshold, and a second terminal holding the text string, the length of the pattern string and the threshold, The first terminal communicates with the second terminal: The first terminal and the second terminal execute a secure approximate pattern matching algorithm. If the Hamming distance between a certain substring of the text string and the pattern string is less than the threshold, the first terminal outputs the substring in the text string. s position; Safe approximate pattern matching algorithms, including: The second terminal randomly selects m pairs of random numbers, which are

The second terminal selects a corresponding random number according to each substring of length m of the text string t, and obtains a text set

where i=1,...,n-m+1; For each j=1,...,m, the first terminal and the second terminal perform a 2-to-1 blind transmission algorithm, and the input of the second terminal is

The input of the first terminal is p _j . After the algorithm is executed, the first terminal obtains the pattern set

For each _i =1, . The input of the terminal is S,m,m-τ, after the algorithm is executed, the first terminal obtains the output set b _i ∈{0,1} ^n-m+1 ; If b _i =1, the first terminal outputs i; Boolean threshold privacy set intersection algorithm, including: The second terminal publishes the public additive homomorphic encryption public key pk ₁ , then the first terminal and the second terminal execute the private set intersection radix algorithm, and the first terminal obtains Enc(pk ₁ ,|C∩S|); The first terminal selects a random number r∈{0,...,p-1}, and performs additive homomorphic calculation to obtain Enc(pk ₁ ,|C∩S|+r)=Enc(pk ₁ ,|C∩S|)· Enc(pk ₁ ,r); The first terminal selects random numbers r′∈{0,…,p-1} and R∈{0,…,p-1}, and prepares a root of r+t,r+t+1,…,r+min (|C|,|S|) polynomial p(·), then calculate polynomial p′(·)=r′·p(·)+R, the coefficients of polynomial p′(·) are a ₀ , a ₁ , …,a _{min(|C|,|S|) +1} ; The first terminal uses the additive homomorphic encryption public key pk ₂ to encrypt the coefficients of the polynomial p'(·), and the encrypted coefficients are obtained as Enc(pk ₂ , a ₀ ), Enc(pk ₂ , a ₁ ), ... ,Enc(pk ₂ ,a _{min(|C|,|S|)+1} ); The first terminal sends the encryption coefficient of the polynomial p'(·) and Enc(pk ₁ , |C∩S|+r) to the second terminal; The second terminal decrypts the received ciphertext to obtain |C∩S|+r, then uses the point |C∩S|+r to calculate the polynomial p′(·) at a loss, and denote the obtained result as Enc(pk ₂ ,R′ ),get:

The second terminal selects a random number r"∈{0,...,p-1} and performs additive homomorphic calculation to obtain Enc(pk ₁ ,R'+r")=Enc(pk ₁ ,R')·Enc(pk ₁ ,r"), and then send it to the first terminal to request its decryption; The first terminal decrypts Enc(pk ₁ , R'+r") and sends the result R'+r" to the second terminal, and the second terminal obtains R' through calculation; The first terminal and the second terminal execute the privacy equality test algorithm, wherein the second terminal inputs R', the first terminal inputs R, and after the algorithm execution ends, the first terminal outputs 0 or 1; where m is the length of the pattern string; n is the length of the text string; τ is the threshold given in the secure approximate pattern matching algorithm; C is the set held by the first terminal; S is the set held by the second terminal; let The security parameter is λ, and the global parameter p is set, where p is a prime number, and its binary length |p|>λ; |C| is the number of elements in the set C; |S| is the number of elements in the set S; t is a Boolean type Thresholds given in the privacy set intersection algorithm.

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