User location information sharing method and system

Abstract

The present invention provides a method and system for sharing user location information, including: sending a location information request to a certificate issuing authority, receiving a temporary session key sent by the certificate issuing authority after verifying the location information request; using the temporary session key to encrypt an anonymous area based on a chaotic algorithm output to obtain encrypted location information, and sending the encrypted location information to a receiving user; after the receiving user verifies and decrypts the encrypted location information through the certificate issuing authority and a location service provider, the receiving user obtains the shared location information. The present invention introduces chaos into the anonymization of user location data to achieve P2P location sharing in a mobile social network, thereby reducing communication overhead, reducing system architecture costs, and taking into account both the availability of data in location anonymity and location sharing schemes and the efficiency of the system.

Description

Technical Field

[0001] The present invention relates to the field of network security technology, and in particular to a method and system for sharing user location information. Background Art

[0002] Mobile Social Networks (MSNs) are complex networks that have the characteristics of both traditional online social networks (OSNs) and location-based social networks (LBSNs). With the rapid development of mobile social networks, location-based services (LBS) have also gained greater development, greatly facilitating users' lives. While users enjoy the many conveniences brought by these applications, their privacy protection is also subject to major security threats.

[0003] There are three common ways of location information leakage: 1) Location servers leak users' location privacy. When users seek location services from location service providers, they must first send their own locations and needs to the location server, and then the location server provides corresponding services to users. At this time, the location server contains information such as the user's location and shared content. Once an attacker obtains the user's location information by attacking the server, it will cause immeasurable losses; 2) Users actively share their location and leak their location privacy. Users can directly share their location information on social media such as Moments, QQ Space or Weibo, which may lead to the leakage of users' location privacy. Attackers can indirectly use certain location service applications to infer users' real locations and movement trajectories. For example, WeChat Sports or other applications that support searching for nearby friends may be maliciously used by attackers to infer users' real locations; 3) Location trajectory data leaks user privacy. Attackers obtain personal sensitive information such as personal hobbies, behavioral habits, lifestyle, etc. by mining and analyzing historical trajectory data. They may also combine information such as payment records or social networks to infer user identities. The goal of location privacy protection is to prevent others from obtaining the user's past or present location or trajectory information without the user's knowledge. The specific goals can be expressed as: 1) increase the uncertainty of the user's identity, hide the user's identity or encrypt the user's identity so that the attacker cannot determine the user's identity; 2) increase the uncertainty of the location, hide the location information or encrypt the location information so that the attacker cannot determine the user's specific location; 3) eliminate the association between the user's identity and location so that the attacker cannot associate the user with the location he visits. There are two privacy concepts in mobile social networks: weak location privacy and strong location privacy. The former means that the attacker can infer that the user is in a privacy area, but cannot determine its exact location. The solution is generally based on location perturbation, spatial anonymity and spatial transformation; the latter means that the attacker cannot infer the user's specific location at all. The solution is often combined with encryption technology. In order to deal with the threats faced by users' location privacy, the common location privacy protection mechanisms currently available are mainly divided into the following three categories: (1) k-anonymity-based schemes; (2) obfuscation-based schemes; (3) differential privacy-based schemes.

[0004] The above scheme has the following problems: Most typical location privacy protection algorithms are based on a centralized architecture and achieve anonymity by introducing a single trusted third party (STTP), that is, an anonymous server. Although the introduction of a trusted third party anonymous server has greatly facilitated the realization of location privacy protection to some extent, its existence also poses the following threats: 1) STTP records the accurate location information of all users and becomes an attractive target for attackers. Once an attacker successfully breaks into the STTP server, the attacker will be able to access all user information processed by the server; 2) All queries submitted by the user end must pass through the STTP server, which not only increases the communication overhead, but also makes the server a central failure point, forming a performance bottleneck; 3) In reality, it is difficult to find a completely trustworthy entity.

[0005] In summary, existing privacy protection mechanisms usually require adding complex algorithms to the original system to process user identity and location data. Although this approach improves the protection of user location privacy, it reduces data availability and system efficiency. Summary of the invention

[0006] The present invention provides a user location information sharing method and system, which are used to solve the defects in the prior art that complex algorithms need to be added when sharing user information, and data availability and system efficiency are easily reduced.

[0007] In a first aspect, the present invention provides a method for sharing user location information, comprising:

[0008] Sending a location information request to a certificate issuing authority, and receiving a temporary session key sent by the certificate issuing authority after verifying the location information request;

[0009] Using the temporary session key to encrypt the anonymous area output based on the chaotic algorithm to obtain encrypted location information, and sending the encrypted location information to a receiving user;

[0010] After the receiving user verifies and decrypts the encrypted location information through the certificate issuing authority and the location service provider, the receiving user obtains the shared location information.

[0011] According to a user location information sharing method provided by the present invention, the sending of a location information request to a certificate issuing authority and the receiving of a temporary session key sent by the certificate issuing authority after verifying the location information request include:

[0012] After the certificate issuing authority verifies the association relationship between the shared user and the receiving user, the temporary session key issued by the certificate issuing authority is received.

[0013] According to a user location information sharing method provided by the present invention, the anonymous area output based on the chaotic algorithm is encrypted using the temporary session key to obtain encrypted location information, and the encrypted location information is sent to a receiving user, including:

[0014] Determine a position accuracy value, a user position coordinate, and a chaotic random coefficient, wherein the position accuracy value is within a preset accuracy interval, and the chaotic random coefficient is within a preset chaotic region;

[0015] Acquire the initial value of the user position coordinates, and determine a chaotic function based on the position accuracy value and the user position coordinates;

[0016] Substitute the initial value of the user position coordinate into the chaotic function, iterate 2k steps, and obtain 2k position values;

[0017] Determine the user position coordinate value based on the positive determination coefficient, the negative determination coefficient and the 2k position values;

[0018] Based on the query radius and the user location coordinate value, a query area is generated, and location values ​​located in the query area are screened out from the 2k location values. If the number of the screened out location values ​​is less than k, iterate again for k steps until the number of the screened out location values ​​is at least k.

[0019] Divide the query area into n×n cells, calculate the historical query probability of each cell according to the historical query times of the cell, sort the filtered position values ​​in descending order based on the historical query probability, and determine the top k-1 position values;

[0020] The top k-1 position values ​​and the user position coordinate value are combined using a k-anonymity algorithm to generate the anonymous area;

[0021] Determine the query request content, use the temporary session key to encrypt the anonymous area, the query request content, the query radius, the chaotic random coefficient and the location accuracy value to obtain the encrypted location information, and send the encrypted location information to the receiving user.

[0022] In a second aspect, the present invention provides a method for sharing user location information, comprising:

[0023] The user to be shared sends a location information request to the certificate issuing authority, and receives a temporary session key sent by the certificate issuing authority after verifying the location information request;

[0024] Receiving encrypted location information obtained by the shared user using the temporary session key to encrypt the anonymous area output based on the chaotic algorithm;

[0025] After the encrypted location information is verified and decrypted by the certificate issuing authority and the location service provider, the shared location information is obtained.

[0026] According to a user location information sharing method provided by the present invention, after the encrypted location information is verified and decrypted by the certificate issuing authority and the location service provider, the shared location information is obtained, including:

[0027] Decrypting the encrypted location information using the temporary session key to obtain decrypted location information, and acquiring the initial location of the shared user based on the decrypted location information;

[0028] Sending a pseudonym registration request to the certificate issuing authority, and receiving the pseudonym, certificate, certificate term and key returned by the certificate issuing authority;

[0029] Encrypting the pseudonym, the certificate, the certificate period and the key using the public key of the location service provider to obtain query request information, and sending the query request information to the location service provider;

[0030] The location service provider uses a private key to decrypt the query request information, and verifies the validity of the pseudonym through the certificate issuing authority. If valid, the certificate issuing authority sends the key to the location service provider;

[0031] The location service provider obtains the location point of interest information in the service database based on the anonymous area, the query request content and the query radius, and symmetrically encrypts the location point of interest information using the key to obtain the encrypted location point of interest information;

[0032] The encrypted location point of interest information is received, and the shared location information is obtained based on the encrypted location point of interest information.

[0033] According to a user location information sharing method provided by the present invention, the obtaining the initial location of the shared user based on the decrypted location information comprises:

[0034] Based on the chaotic random coefficient, the position accuracy value and the k value in the decrypted position information, calculating the position set after nk iterations when each position in the anonymous area is used as an initial value, where n is greater than 1;

[0035] If all positions within the anonymous area belong to the position set, the initial value is determined to be the initial position of the sharing user.

[0036] In a third aspect, the present invention further provides a user location information sharing system, comprising:

[0037] A sending module, used to send a location information request to a certificate issuing authority, and receive a temporary session key sent by the certificate issuing authority after verifying the location information request;

[0038] An encryption module, used to encrypt the anonymous area output based on the chaotic algorithm using the temporary session key to obtain encrypted position information, and send the encrypted position information to a receiving user;

[0039] The acquisition module is used for the receiving user to obtain the shared location information after the receiving user verifies and decrypts the encrypted location information through the certificate issuing authority and the location service provider.

[0040] In a fourth aspect, the present invention further provides a user location information sharing system, comprising:

[0041] A first receiving module, configured to send a location information request to a certificate issuing authority by a user to be shared, and receive a temporary session key sent by the certificate issuing authority after verifying the location information request;

[0042] A second receiving module is used to receive encrypted location information obtained by the shared user using the temporary session key to encrypt the anonymous area output based on the chaotic algorithm;

[0043] The processing module is used to obtain the shared location information after verifying and decrypting the encrypted location information through the certificate issuing authority and the location service provider.

[0044] In a fifth aspect, the present invention further provides an electronic device, comprising a memory, a processor, and a computer program stored in the memory and executable on the processor, wherein when the processor executes the program, the method for sharing user location information as described in any one of the above is implemented.

[0045] In a sixth aspect, the present invention further provides a non-transitory computer-readable storage medium having a computer program stored thereon, which, when executed by a processor, implements any of the user location information sharing methods described above.

[0046] In a seventh aspect, the present invention further provides a computer program product, comprising a computer program, which, when executed by a processor, implements any of the user location information sharing methods described above.

[0047] The user location information sharing method and system provided by the present invention realize P2P location sharing in mobile social networks by introducing chaos into the anonymization of user location data, thereby reducing communication overhead, lowering system architecture cost, and taking into account the availability of data in location anonymity and location sharing solutions as well as the efficiency of the system. BRIEF DESCRIPTION OF THE DRAWINGS

[0048] In order to more clearly illustrate the technical solutions in the present invention or the prior art, the following briefly introduces the drawings required for use in the embodiments or the description of the prior art. Obviously, the drawings described below are some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0049] Figure 1 This is one of the flow charts of the user location information sharing method provided by the present invention;

[0050] Figure 2 This is a diagram of the user anonymity solution architecture provided by the present invention;

[0051] Figure 3 It is a diagram of the architecture of the P2P location sharing solution provided by the present invention;

[0052] Figure 4 It is a principle diagram of the user location information protection method provided by the present invention;

[0053] Figure 5 This is the second flow chart of the user location information sharing method provided by the present invention;

[0054] Figure 6 It is one of the structural schematic diagrams of the user location information sharing system provided by the present invention;

[0055] Figure 7 This is the second structural diagram of the user location information sharing system provided by the present invention;

[0056] Figure 8 It is a structural schematic diagram of the electronic device provided by the present invention. DETAILED DESCRIPTION

[0057] In order to make the purpose, technical solution and advantages of the present invention clearer, the technical solution of the present invention will be clearly and completely described below in conjunction with the drawings of the present invention. Obviously, the described embodiments are part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0058] In view of the defects in the prior art, the present invention proposes a user location information sharing method, which will utilize the characteristics of the chaotic system to achieve anonymity, avoid the introduction of a third-party anonymous server, and further realize P2P location sharing in mobile social networks, thereby improving data availability and system efficiency.

[0059] Figure 1 is one of the flow charts of the user location information sharing method provided by the present invention, and the corresponding execution subject is the sharing user, such as Figure 1 As shown, including:

[0060] Step 101, sending a location information request to a certificate issuing authority, and receiving a temporary session key sent by the certificate issuing authority after verifying the location information request;

[0061] Step 102, using the temporary session key to encrypt the anonymous area output based on the chaos algorithm to obtain encrypted location information, and sending the encrypted location information to a receiving user;

[0062] Step 103: After the receiving user verifies and decrypts the encrypted location information through the certificate issuing authority and the location service provider, the receiving user obtains the shared location information.

[0063] It should be noted that the anonymity scheme in the present invention is based on a P2P architecture design without the participation of a third party. Figure 2 As shown in Figure 1, the model mainly includes two entities: the mobile user terminal User and the location service provider LSP. There is no anonymous server involved, and the anonymous operation is realized by the user terminal calculation. By adopting this architecture, the security risk of third-party servers leaking user privacy information is eliminated, and the performance bottleneck caused by single point failure in the TTP architecture is also avoided.

[0064] Mobile User Terminal User / Client: A user can be an operating device with wireless communication, computing and storage capabilities, but more importantly, with positioning capabilities. In the model of the present invention, the user terminal performs various functions such as calculation, location prediction, selection of virtual locations, caching and refinement of query results.

[0065] Location Service Provider LSP: LSP is an online location service solution provider, such as Twitter, Foursquare or Google Maps, which operates some LBS servers with location service related resources to provide comprehensive location-based services to mobile users. In the model of the present invention, LSP is considered to be an honest but curious entity, which may also leak sensitive user information.

[0066] Another example Figure 3 As shown, in Figure 2 On this basis, a certificate issuing authority CA is added to form a P2P location sharing solution.

[0067] Certificate Authority CA: This entity is completely trusted and its main function is to register different users and LSPs. In our model, CA can also issue pseudonyms and corresponding certificates and keys to users.

[0068] In summary, in this model, the certificate issuing authority CA and the user User are considered to be fully trusted entities. In addition, it is assumed that the two communication channels between CA and User and between CA and LSP are secure. At the same time, existing security authentication technologies such as two-factor authentication and multi-factor authentication can be used to ensure that users and LSPs authenticate themselves at CA.

[0069] Specifically, the shared user, which can generally be understood as a sender, sends a location information request to the certificate issuing authority, and the shared user and the receiving user jointly receive a temporary session key sent by the certificate issuing authority after verifying the location information request;

[0070] After the shared user calculates the anonymous area using the chaos algorithm, the anonymous area is encrypted using the temporary session key and the encrypted location information is sent to the receiving user;

[0071] After the receiving user has been authenticated and encrypted by the certificate issuing authority and the location service provider, the receiving user obtains the shared location information sent by the location service provider to the shared user.

[0072] The present invention introduces chaos into the anonymization of user location data to achieve P2P location sharing in mobile social networks, thereby reducing communication overhead, lowering system architecture costs, and taking into account both location anonymity and data availability in location sharing solutions and system efficiency.

[0073] Based on the above embodiment, step 101 includes:

[0074] After the certificate issuing authority verifies the association relationship between the shared user and the receiving user, the temporary session key issued by the certificate issuing authority is received.

[0075] Specifically, when the shared user sends a request to the certificate issuing authority CA, the CA will verify the friendship between the shared user and the receiving user. After the verification is passed, the temporary session key SK is sent to the shared user and the receiving user. AB .

[0076] The present invention verifies the authority of both sharing parties through a certificate issuing agency and adopts a unified temporary session key to facilitate subsequent unified decryption and encryption operations on the location information.

[0077] Based on the above embodiment, step 102 includes:

[0078] Determine a position accuracy value, a user position coordinate, and a chaotic random coefficient, wherein the position accuracy value is within a preset accuracy interval, and the chaotic random coefficient is within a preset chaotic region;

[0079] Acquire the initial value of the user position coordinates, and determine a chaotic function based on the position accuracy value and the user position coordinates;

[0080] Substitute the initial value of the user position coordinate into the chaotic function, iterate 2k steps, and obtain 2k position values;

[0081] Determine the user position coordinate value based on the positive determination coefficient, the negative determination coefficient and the 2k position values;

[0082] Based on the query radius and the user location coordinate value, a query area is generated, and location values ​​located in the query area are screened out from the 2k location values. If the number of the screened out location values ​​is less than k, iterate again for k steps until the number of the screened out location values ​​is at least k.

[0083] Divide the query area into n×n cells, calculate the historical query probability of each cell according to the historical query times of the cell, sort the filtered position values ​​in descending order based on the historical query probability, and determine the top k-1 position values;

[0084] The top k-1 position values ​​and the user position coordinate value are combined using a k-anonymity algorithm to generate the anonymous area;

[0085] Determine the query request content, use the temporary session key to encrypt the anonymous area, the query request content, the query radius, the chaotic random coefficient and the location accuracy value to obtain the encrypted location information, and send the encrypted location information to the receiving user.

[0086] Specifically, any shared user u i Customize the location precision value m (m∈[0,3]) according to privacy requirements, and the user location coordinates (x i ,y i ), x i and i Respectively represent the longitude and latitude of the user's location. For example, according to the API provided by Amap, we can know that the location of a park is (117.149437, 39.010107). At the same time, the chaotic random coefficient λ is selected. The chaotic behavior of the function depends entirely on λ. In order to make the function run in the most chaotic area, λ is defined between 3.99 and 4. The user randomly selects a number between 3.99-4 as the value of λ.

[0087] It should be noted that a chaotic system refers to a system in which there are seemingly random irregular movements in a deterministic system, and its behavior is uncertain, non-repeatable, and unpredictable. This is the chaotic phenomenon. The logistic map is currently the most widely used type of nonlinear dynamic discrete chaotic map system. The chaotic function of this map is:

[0088] x(n+1)=λx(n)(1-x(n))

[0089] Among them, the parameters λ∈(0,4], x(n)∈(0,1), when 3.5699<λ≤4, the system is in a chaotic state.

[0090] Furthermore, 2k positions are generated according to the above chaotic function, and according to the user u i The position (x i ,y i ), calculate the initial value x of the user's position coordinates i (0),y i (0), then:

[0091]

[0092] And respectively x i (0),y i (0) is substituted into the chaotic function as the initial value, and iterates for 2k steps to obtain (x i (1),y i (1)),(x i (2),y i (2)),...,(xi(2k),y i (2k)).

[0093] According to the obtained iteration value, 2k positions are found, and the coordinates of the nth position are (Lx i (n), Ly i (n)), the calculation process is as follows:

[0094]

[0095] Among them, c x and c y Is the positive and negative determination coefficient, if x i is a positive number, then c x =1, if x i If c is negative, x =-1.

[0096] The user terminal Client determines its location (x i ,y i) and query radius R, generate a region Reg with radius R, and select the position located in Reg from the calculated 2k positions. If the number of selected positions is less than k, iterate k steps again and repeat this process until at least k positions are selected.

[0097] Then, position selection is performed. Assuming that Reg is divided into n×n cells, the historical query probability of each cell can be calculated according to the number of historical queries in the cell. The positions selected in the previous step are sorted in descending order according to the historical query probability corresponding to each position, and the first k-1 positions are selected. These k-1 positions and the user position (x i ,y i ) forms a Region and sends it to the location service provider LSP to achieve k-anonymity.

[0098] Shared users (i.e. Figure 4 Alice in the above anonymity scheme forms a A ,y A ) includes an anonymous region Region of k locations, to the receiving user (i.e. Figure 4 Bob in sends {Region,Q,R,λ,m} and uses SK AB Encryption. Among them, Q is the query request content finally sent to LSP, R is the query radius, λ is the randomly generated chaos coefficient, and m is the location accuracy customized by Alice.

[0099] The present invention adopts a chaos-based anonymity algorithm to obtain the anonymous area of ​​shared users, and realizes P2P location sharing by using chaos. The proposed lightweight location anonymity and P2P location sharing scheme based on chaos can better utilize the chaos characteristics to realize k-anonymity and is applied to P2P location sharing, thereby improving the data availability and system efficiency of anonymity and location sharing schemes in mobile social networks.

[0100] Figure 5 This is the second flow chart of the user location information sharing method provided by the present invention, and the corresponding execution subject is the receiving user, such as Figure 5 As shown, including:

[0101] Step 201, the user to be shared sends a location information request to a certificate issuing authority, and receives a temporary session key sent by the certificate issuing authority after verifying the location information request;

[0102] Step 202, receiving encrypted location information obtained by the shared user using the temporary session key to encrypt the anonymous area output based on the chaotic algorithm;

[0103] Step 203: After the encrypted location information is verified and decrypted by the certificate issuing authority and the location service provider, the shared location information is obtained.

[0104] Specifically, the shared user, which can generally be understood as a sender, sends a location information request to the certificate issuing authority, and the shared user and the receiving user jointly receive a temporary session key sent by the certificate issuing authority after verifying the location information request;

[0105] After the shared user calculates the anonymous area using the chaos algorithm, the anonymous area is encrypted using the temporary session key and the encrypted location information is sent to the receiving user;

[0106] After the receiving user has been authenticated and encrypted by the certificate issuing authority and the location service provider, the receiving user obtains the shared location information sent by the location service provider to the shared user.

[0107] The present invention introduces chaos into the anonymization of user location data to achieve P2P location sharing in mobile social networks, thereby reducing communication overhead, lowering system architecture costs, and taking into account both location anonymity and data availability in location sharing solutions and system efficiency.

[0108] Based on the above embodiment, step 203 includes:

[0109] Decrypting the encrypted location information using the temporary session key to obtain decrypted location information, and acquiring the initial location of the shared user based on the decrypted location information;

[0110] Sending a pseudonym registration request to the certificate issuing authority, and receiving the pseudonym, certificate, certificate term and key returned by the certificate issuing authority;

[0111] Encrypting the pseudonym, the certificate, the certificate period and the key using the public key of the location service provider to obtain query request information, and sending the query request information to the location service provider;

[0112] The location service provider uses a private key to decrypt the query request information, and verifies the validity of the pseudonym through the certificate issuing authority. If valid, the certificate issuing authority sends the key to the location service provider;

[0113] The location service provider obtains the location point of interest information in the service database based on the anonymous area, the query request content and the query radius, and symmetrically encrypts the location point of interest information using the key to obtain the encrypted location point of interest information;

[0114] The encrypted location point of interest information is received, and the shared location information is obtained based on the encrypted location point of interest information.

[0115] Wherein, obtaining the initial location of the shared user based on the decrypted location information includes:

[0116] Based on the chaotic random coefficient, the position accuracy value and the k value in the decrypted position information, calculating the position set after nk iterations when each position in the anonymous area is used as an initial value, where n is greater than 1;

[0117] If all positions within the anonymous area belong to the position set, the initial value is determined to be the initial position of the sharing user.

[0118] Specifically, when Bob receives the message sent by Alice, he uses SK AB Decrypt and get {Region, Q, R, λ, m}. According to λ, m and k, calculate each position in the Region as the initial value. Iterate nk (where n is an integer > 1) times to get the set R of positions. If all the positions in the Region belong to R, then the initial position is the position where Alice is located.

[0119] Bob sends a request to the CA to register a pseudonym. Then he encrypts the information with the LSP's public key and sends it to the LSP.

[0120] Upon receiving the query request message MSG B2S After that, LSP uses its own private key SK S Decryption is performed and the validity of the user pseudonym is verified by the CA. If valid, the CA sends the user key to the LSP.

[0121] LSP queries the POIs in the service database based on the anonymous region Region, request content Q and query radius R, and then uses the user key Symmetrically encrypt these POIs and get Finally, LSP sends the result to Bob.

[0122] The present invention performs multiple authentications on the shared location information through the certificate issuing authority and the location service provider, thereby effectively ensuring the privacy protection of the shared location information and enhancing the data availability.

[0123] The user location information sharing system provided by the present invention is described below. The user location information sharing system described below and the user location information sharing method described above can be referenced to each other.

[0124] Figure 6is one of the structural diagrams of the user location information sharing system provided by the present invention, such as Figure 6 As shown, it includes: a sending module 61, an encryption module 62 and an acquisition module 63, wherein:

[0125] The sending module 61 is used to send a location information request to a certificate issuing authority, and receive a temporary session key sent by the certificate issuing authority after verifying the location information request; the encryption module 62 is used to use the temporary session key to encrypt the anonymous area based on the output of the chaos algorithm to obtain encrypted location information, and send the encrypted location information to the receiving user; the acquisition module 63 is used for the receiving user to obtain the shared location information after the receiving user verifies and decrypts the encrypted location information through the certificate issuing authority and the location service provider.

[0126] The present invention introduces chaos into the anonymization of user location data to achieve P2P location sharing in mobile social networks, thereby reducing communication overhead, lowering system architecture costs, and taking into account both location anonymity and data availability in location sharing solutions and system efficiency.

[0127] Figure 7 This is the second structural diagram of the user location information sharing system provided by the present invention. Figure 7 As shown, it includes: a first receiving module 71, a second receiving module 72 and a processing module 73, wherein:

[0128] The first receiving module 71 is used for the shared user to send a location information request to the certificate issuing authority, and receive the temporary session key sent by the certificate issuing authority after verifying the location information request; the second receiving module 72 is used to receive the encrypted location information obtained by the shared user after encrypting the anonymous area output based on the chaotic algorithm using the temporary session key; the processing module 73 is used to obtain the shared location information after verifying and decrypting the encrypted location information through the certificate issuing authority and the location service provider.

[0129] The present invention introduces chaos into the anonymization of user location data to achieve P2P location sharing in mobile social networks, thereby reducing communication overhead, lowering system architecture costs, and taking into account both location anonymity and data availability in location sharing solutions and system efficiency.

[0130] Figure 8 An example of a physical structure diagram of an electronic device is shown in FIG. Figure 8As shown, the electronic device may include: a processor 810, a communication interface 820, a memory 830 and a communication bus 840, wherein the processor 810, the communication interface 820 and the memory 830 complete mutual communication through the communication bus 840. The processor 810 may call the logic instructions in the memory 830 to execute the user location information sharing method, which includes: sending a location information request to a certificate issuing authority, receiving a temporary session key sent by the certificate issuing authority after verifying the location information request; using the temporary session key to encrypt the anonymous area output based on the chaos algorithm to obtain encrypted location information, and sending the encrypted location information to the receiving user; after the receiving user verifies and decrypts the encrypted location information through the certificate issuing authority and the location service provider, the receiving user obtains the shared location information.

[0131] In addition, the logic instructions in the above-mentioned memory 830 can be implemented in the form of a software functional unit and can be stored in a computer-readable storage medium when it is sold or used as an independent product. Based on such an understanding, the technical solution of the present invention, in essence, or the part that contributes to the prior art or the part of the technical solution, can be embodied in the form of a software product, and the computer software product is stored in a storage medium, including a number of instructions for a computer device (which can be a personal computer, a server, or a network device, etc.) to perform all or part of the steps of the method described in each embodiment of the present invention. The aforementioned storage medium includes: U disk, mobile hard disk, read-only memory (ROM, Read-Only Memory), random access memory (RAM, Random Access Memory), disk or optical disk and other media that can store program codes.

[0132] On the other hand, the present invention also provides a computer program product, which includes a computer program. The computer program can be stored on a non-transitory computer-readable storage medium. When the computer program is executed by a processor, the computer can execute the user location information sharing method provided by the above methods, which method includes: sending a location information request to a certificate issuing authority, receiving a temporary session key sent by the certificate issuing authority after verifying the location information request; using the temporary session key to encrypt an anonymous area output based on a chaotic algorithm to obtain encrypted location information, and sending the encrypted location information to a receiving user; after the receiving user verifies and decrypts the encrypted location information through the certificate issuing authority and the location service provider, the receiving user obtains the shared location information.

[0133] On the other hand, the present invention also provides a non-transitory computer-readable storage medium having a computer program stored thereon. When the computer program is executed by a processor, it is implemented to execute the user location information sharing method provided by the above-mentioned methods, the method comprising: sending a location information request to a certificate issuing authority, receiving a temporary session key sent by the certificate issuing authority after verifying the location information request; using the temporary session key to encrypt an anonymous area output based on a chaotic algorithm to obtain encrypted location information, and sending the encrypted location information to a receiving user; after the receiving user verifies and decrypts the encrypted location information through the certificate issuing authority and the location service provider, the receiving user obtains the shared location information.

[0134] The device embodiments described above are merely illustrative, wherein the units described as separate components may or may not be physically separated, and the components displayed as units may or may not be physical units, that is, they may be located in one place, or they may be distributed on multiple network units. Some or all of the modules may be selected according to actual needs to achieve the purpose of the scheme of this embodiment. Ordinary technicians in this field can understand and implement it without paying creative labor.

[0135] Through the description of the above implementation methods, those skilled in the art can clearly understand that each implementation method can be implemented by means of software plus a necessary general hardware platform, and of course, it can also be implemented by hardware. Based on this understanding, the above technical solution is essentially or the part that contributes to the prior art can be embodied in the form of a software product, and the computer software product can be stored in a computer-readable storage medium, such as ROM / RAM, a disk, an optical disk, etc., including a number of instructions for a computer device (which can be a personal computer, a server, or a network device, etc.) to execute the methods described in each embodiment or some parts of the embodiments.

[0136] 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 make equivalent replacements for some of the technical features therein. However, these modifications or replacements do not deviate the essence of the corresponding technical solutions from the spirit and scope of the technical solutions of the embodiments of the present invention.

Claims

1. A method for sharing user location information, characterized in that: include: Sending a location information request to a certificate issuing authority, and receiving a temporary session key sent by the certificate issuing authority after verifying the location information request; Using the temporary session key to encrypt the anonymous area output based on the chaotic algorithm to obtain encrypted location information, and sending the encrypted location information to a receiving user; After the receiving user verifies and decrypts the encrypted location information through the certificate issuing authority and the location service provider, the receiving user obtains the shared location information; The anonymous region based on the output of the chaos algorithm is obtained in the following way: Determine a position accuracy value, a user position coordinate, and a chaotic random coefficient, wherein the position accuracy value is within a preset accuracy interval, and the chaotic random coefficient is within a preset chaotic region; Acquire the initial value of the user position coordinates, and determine a chaotic function based on the position accuracy value and the user position coordinates; Substitute the initial value of the user position coordinate into the chaotic function, iterate 2k steps, and obtain 2k position values; Determine the user position coordinate value based on the positive determination coefficient, the negative determination coefficient and the 2k position values; Based on the query radius and the user location coordinate value, a query area is generated, and location values ​​located in the query area are screened out from the 2k location values. If the number of the screened out location values ​​is less than k, iterate again for k steps until the number of the screened out location values ​​is at least k. Divide the query area into n×n cells, calculate the historical query probability of each cell according to the historical query times of the cell, sort the filtered position values ​​in descending order based on the historical query probability, and determine the top k-1 position values; The top k-1 position values ​​and the user position coordinate value are combined using a k-anonymity algorithm to generate the anonymous area.

2. The user location information sharing method according to claim 1, characterized in that: The sending of the location information request to the certificate issuing authority and receiving the temporary session key sent by the certificate issuing authority after verifying the location information request comprises: After the certificate issuing authority verifies the association relationship between the shared user and the receiving user, the temporary session key issued by the certificate issuing authority is received.

3. The user location information sharing method according to claim 1, characterized in that: The method of encrypting the anonymous area outputted by the chaotic algorithm using the temporary session key to obtain encrypted location information and sending the encrypted location information to a receiving user comprises: Determine the query request content, use the temporary session key to encrypt the anonymous area, the query request content, the query radius, the chaotic random coefficient and the location accuracy value to obtain the encrypted location information, and send the encrypted location information to the receiving user.

4. A method for sharing user location information, characterized in that: include: After the shared user sends a location information request to the certificate issuing authority, the receiving user receives a temporary session key sent by the certificate issuing authority after verifying the location information request; The receiving user receives the encrypted location information obtained by the sharing user using the temporary session key to encrypt the anonymous area output based on the chaotic algorithm; After verifying and decrypting the encrypted location information through the certificate issuing authority and the location service provider, the shared location information is obtained; The anonymous region based on the output of the chaos algorithm is obtained in the following way: Determine a position accuracy value, a user position coordinate, and a chaotic random coefficient, wherein the position accuracy value is within a preset accuracy interval, and the chaotic random coefficient is within a preset chaotic region; Acquire the initial value of the user position coordinates, and determine a chaotic function based on the position accuracy value and the user position coordinates; Substitute the initial value of the user position coordinate into the chaotic function, iterate 2k steps, and obtain 2k position values; Determine the user position coordinate value based on the positive determination coefficient, the negative determination coefficient and the 2k position values; Based on the query radius and the user location coordinate value, a query area is generated, and location values ​​located in the query area are screened out from the 2k location values. If the number of the screened out location values ​​is less than k, iterate again for k steps until the number of the screened out location values ​​is at least k. Divide the query area into n×n cells, calculate the historical query probability of each cell according to the historical query times of the cell, sort the filtered position values ​​in descending order based on the historical query probability, and determine the top k-1 position values; The top k-1 position values ​​and the user position coordinate value are combined using a k-anonymity algorithm to generate the anonymous area.

5. The user location information sharing method according to claim 4, characterized in that: After the encrypted location information is verified and decrypted by the certificate issuing authority and the location service provider, the shared location information is obtained, including: Decrypting the encrypted location information using the temporary session key to obtain decrypted location information, and acquiring the initial location of the shared user based on the decrypted location information; Sending a pseudonym registration request to the certificate issuing authority, and receiving the pseudonym, certificate, certificate term and key returned by the certificate issuing authority; Encrypting the pseudonym, the certificate, the certificate period and the key using the public key of the location service provider to obtain query request information, and sending the query request information to the location service provider; The location service provider uses a private key to decrypt the query request information, and verifies the validity of the pseudonym through the certificate issuing authority. If valid, the certificate issuing authority sends the key to the location service provider; The location service provider obtains the location point of interest information in the service database based on the anonymous area, the query request content and the query radius, and symmetrically encrypts the location point of interest information using the key to obtain the encrypted location point of interest information; The encrypted location point of interest information is received, and the shared location information is obtained based on the encrypted location point of interest information.

6. The user location information sharing method according to claim 5, characterized in that: The obtaining the initial location of the shared user based on the decrypted location information includes: Based on the chaotic random coefficient, the position accuracy value and the k value in the decrypted position information, calculating the position set after nk iterations when each position in the anonymous area is used as an initial value, where n is greater than 1; If all positions within the anonymous area belong to the position set, the initial value is determined to be the initial position of the sharing user.

7. A user location information sharing system, characterized in that: include: A sending module, used to send a location information request to a certificate issuing authority, and receive a temporary session key sent by the certificate issuing authority after verifying the location information request; An encryption module, used to encrypt the anonymous area output based on the chaotic algorithm using the temporary session key to obtain encrypted position information, and send the encrypted position information to a receiving user; An acquisition module, configured to allow the receiving user to acquire the shared location information after the receiving user verifies and decrypts the encrypted location information through the certificate issuing authority and the location service provider; The sending module, the encryption module and the acquisition module cooperate with each other to execute the user location information sharing method as described in any one of claims 1 to 3.

8. A user location information sharing system, characterized in that: include: A first receiving module, configured to send a location information request to a certificate issuing authority by a user to be shared, and receive a temporary session key sent by the certificate issuing authority after verifying the location information request; A second receiving module is used to receive encrypted location information obtained by the shared user using the temporary session key to encrypt the anonymous area output based on the chaotic algorithm; A processing module, configured to obtain the shared location information after verifying and decrypting the encrypted location information through the certificate issuing authority and the location service provider; The first receiving module, the second receiving module and the processing module cooperate with each other to execute the user location information sharing method as described in any one of claims 4 to 6.

9. An electronic device comprising a memory, a processor, and a computer program stored in the memory and executable on the processor, wherein: When the processor executes the program, the user location information sharing method according to any one of claims 1 to 6 is implemented.

10. A non-transitory computer-readable storage medium having a computer program stored thereon, characterized in that: When the computer program is executed by a processor, the user location information sharing method according to any one of claims 1 to 6 is implemented.

Images