WO2020140626A1

WO2020140626A1 - Salt-based data possession verification method and terminal device

Info

Publication number: WO2020140626A1
Application number: PCT/CN2019/118156
Authority: WO
Inventors: 雷琼; 郑映锋
Original assignee: 平安科技（深圳）有限公司
Priority date: 2019-01-04
Filing date: 2019-11-13
Publication date: 2020-07-09
Also published as: CN109639436A

Abstract

The present application is applicable to the technical field of computer applications, and provides a salt-based data possession verification method, a terminal device, and a computer non-volatile readable storage medium. The method comprises: by randomly generating a salt, generating a first data abstract according to the salt and source data stored in the local; then sending the salt to a target node storing the source data; calculating by the target node according to the data and salt stored in the target node so as to obtain a second data abstract; finally, comparing the first data abstract and the second data abstract, and determining whether data stored in the target node is complete according to a comparison result. Salt degree of the original data and the storage data is increased and abstracts thereof are extracted, and salts randomly generated by a system are different, so that data abstracts are random at a certain degree, and a storage node cannot retain the data abstract of the original data. Therefore, the reliability of data integrity verification is ensured, and the security and integrity of data stored by a peer-to-peer network (P2P) node are improved.

Description

Salt value-based data possession verification method and terminal equipment

This application requires the priority of the Chinese patent application submitted to the China Patent Office on January 4, 2019, with the application number 201910008653.7 and the invention titled "Data Holdability Verification Method and Terminal Equipment Based on Salt Value." The reference is incorporated in this application.

Technical field

The present application belongs to the field of computer application technology, and particularly relates to a salt value-based data possession verification method, terminal device, and computer non-volatile readable storage medium.

Background technique

When the amount of data faced by the storage service of the cloud platform is getting larger and larger, and the required storage cost is getting higher and higher, in the prior art, the entire data file is stored separately in different In the node, but P2P has untrustworthy characteristics, how to verify that the P2P storage point honestly stores your data, some existing practices are handled by using full-text content HASH and other methods. However, in this way, in the application process, the node that stores the data can modify or delete the stored data after saving the data summary, so that when the data is all verified for data possession, the saved data can be directly The abstract is sent to the terminal of the data owner for verification, and the verification process of the data owner is deceived by forging the data summary, and the reliability of data integrity verification cannot be guaranteed.

technical problem

In view of this, the embodiments of the present application provide a salt value-based data possession verification method, terminal device, and computer non-volatile readable storage medium, to solve the problem of integrity of stored data in verification fragments in the prior art The problem of low reliability during sex.

Technical solution

The first aspect of the embodiments of the present application provides a salt value-based data possession verification method, including:

Randomly generate a salt value, and generate a first data summary based on the salt value and the source data held by the data owner;

Sending the salt value to a target node; the target node is a node that stores the source data;

Receiving a second data summary sent by the target node; the second data summary is generated by the target node according to the salt value and currently stored data corresponding to the source data;

Comparing the first data summary with the second data summary, and verifying whether the stored data stored by the target node is complete according to the comparison result.

A second aspect of an embodiment of the present application provides a terminal device, including a memory, a processor, and computer-readable instructions stored in the memory and executable on the processor, and the processor executes the computer The following steps are realized when the instructions are readable:

A third aspect of the embodiments of the present application provides a terminal device, including:

A first summary unit for randomly generating a salt value, and generating a first data summary according to the salt value and the source data held by the data owner;

A sending unit, configured to send the salt value to a target node; the target node is a node that stores the source data;

A second summary unit, configured to receive a second data summary sent by the target node; the second data summary is generated by the target node according to the salt value and currently stored data corresponding to the source data;

The verification unit is configured to compare the first data digest with the second data digest, and verify whether the stored data stored by the target node is complete according to the comparison result.

A fourth aspect of the embodiments of the present application provides a computer nonvolatile readable storage medium. The computer storage medium stores computer readable instructions. The computer readable instructions include program instructions. When the processor executes, the processor is caused to execute the method of the first aspect.

Beneficial effect

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

In the embodiment of the present application, a salt value is randomly generated, a first data summary is generated according to the salt value and the source data stored locally, and then the salt value is sent to the target node storing the source data, and the target node according to the stored data and The second data summary obtained by calculating the salt value, and finally comparing the first data summary with the second data summary, and determining whether the data stored by the target node is complete according to the comparison result, by adding salinity to the original data and the stored data And perform data summary. Due to the different salt values randomly generated by the system, the data summary is also accompanied by a certain degree of randomness, and the storage node cannot retain the data summary of the original data, ensuring the reliability of data integrity verification and improving P2P The security and integrity of the data stored by the nodes.

BRIEF DESCRIPTION

In order to more clearly explain the technical solutions in the embodiments of the present application, the following will briefly introduce the drawings used in the embodiments or the description of the prior art. Obviously, the drawings in the following description are only for the application In some embodiments, for those of ordinary skill in the art, without paying creative labor, other drawings may be obtained based on these drawings.

FIG. 1 is a flowchart of a salt value-based data possession verification method provided in Embodiment 1 of the present application;

FIG. 2 is a flowchart of a salt value-based data possession verification method provided by Embodiment 2 of the present application;

3 is a schematic diagram of a terminal device provided in Embodiment 3 of this application;

4 is a schematic diagram of a terminal device provided in Embodiment 4 of the present application.

Embodiments of the invention

In the following description, for the purpose of illustration rather than limitation, specific details such as specific system structures and technologies are proposed to thoroughly understand the embodiments of the present application. However, those skilled in the art should understand that the present application can also be implemented in other embodiments without these specific details. In other cases, detailed descriptions of well-known systems, devices, circuits, and methods are omitted to avoid unnecessary details hindering the description of the present application.

In order to explain the technical solutions described in the present application, the following will be described with specific embodiments.

Referring to FIG. 1, FIG. 1 is a flowchart of a salt value-based data possession verification method provided in Embodiment 1 of the present application. In this embodiment, the execution subject of the data possession verification method based on the salt value is a terminal. Terminals include but are not limited to mobile terminals such as smart phones, tablet computers, and wearable devices, and may also be desktop computers. As shown in the figure, the salt value-based data possession verification method may include the following steps:

S101: Randomly generate a salt value, and generate a first data summary according to the salt value and the source data held by the data owner.

For traditional distributed systems, it is nothing more than to build some servers in different areas, and then store data on these servers. It solves some of the problems of centralized storage, but there are also problems such as the server becoming the bottleneck and the inconvenience of access due to bandwidth. Therefore, P2P distributed storage came into being. Peer-to-peer (Peer to Peer, P2P) distributed storage is to let customers also become servers. When storing data, it also provides space for others to store. This is a good solution to the bottleneck caused by the lack of servers, and it can be improved in speed. But it also brings a lot of problems, such as data stability, consistency, security, privacy and anti-attack will be affected more or less. This embodiment is mainly directed to the problem of data integrity, because in many cases, we store data with a large amount of data in a P2P node, and the node cannot guarantee the security, privacy and integrity of the data, but is complete Sex is a more important data attribute than privacy. If integrity is threatened, our data processing system will not have a complete and safe data operation foundation, and P2P nodes are vulnerable to attacks or storage and processing. In the event of a failure, the integrity of the data in the P2P node currently storing the source data needs to be detected in a timely manner. By adding the salinity value to the data in the P2P node, it is verified whether the data stored in the current node is the same as the source data, and whether the original data is completely stored. In this scheme, the source data is used to represent the initial data, that is, the standard data for data storage. These data are stored in the local server, used to compare these data with the data stored in the P2P node, and verify the P2P node. Data integrity.

In this embodiment, the data owner is used to represent the owner and user of the source data. The data owner can process the data and send the data, but because of the large amount of source data, the data owner will All data is sent to other storage nodes. Therefore, in this solution, the storage node is the node used to store the source data of all the data winners.

In the process of generating the first data summary, a salt value is randomly generated first. In cryptography, salt refers to inserting a specific string at any fixed position of the password to let the hashed result and the original password be scattered. The results do not match, this process is called adding salt. Normally, when a field is hashed, for example, the MD5 algorithm, a hash value is generated, and the hashed value is generally unable to obtain the original field through a specific algorithm. But in some cases, such as a large rainbow table, by searching the MD5 value in the table, it is possible to find the real field content corresponding to the hash value in a very short time. The hashed value after salting can greatly reduce the risk of password leakage caused by the theft of user data. Even though the original content corresponding to the hashed value is found through the rainbow table, but because of the salting, The inserted character string disturbs the real password, which greatly reduces the probability of obtaining the real password.

The implementation process of salting is usually to add specific characters at specific positions of the field that needs to be hashed, to disrupt the original string, and to change the hash result generated by it. For example, the source data owned by the data owner is: x7faqgjw. After MD5 hashing, the result is 455e0e5c2bc109deae749e7ce0cdd397. However, due to insufficient number of source data bits in the data owner, the hash result of short data is easily cracked by the rainbow table. Therefore, add a specific string at the end of the source data owned by the data owner: x7faqgjwabcdefghijklmnopqrstuvwxyz. In summary, the number of source data digits after salt addition is longer, and the result of hashing has also changed: 4a1690d5eb6c126ef68606dda68c2f79.

In actual use, the source data owned by the data owner can also be fixed and salted by inserting a specific number of digits, in reverse order, or by multiple methods, making the hash result less likely to be cracked or the original data. And can prevent the storage node from saving and denying the summary of the source data.

S102: Send the salt value to a target node; the target node is a node that stores the source data.

After generating the first data summary, the salt value is sent to the target node. In this embodiment, the target node is a node that stores source data.

It should be noted that, in this embodiment, there may be one storage node storing source data, or at least two storage nodes. When there are multiple storage nodes, the average amount of data may be calculated according to the size of the source data. The storage node stores the same amount of data, or it can be stored according to the data block or directory in the source data. Therefore, when there are at least two target nodes that store source data, the same salt value can be sent to each target node. This can ensure the efficiency of data integrity verification, but it cannot guarantee that the target nodes can communicate with each other. In the case of, other nodes will also obtain the same salt value, and then generate or compile the same data digest as the first data digest based on the modified stored data, and submit it to the data owner's expiration behavior.

In order to ensure the security and reliability of the source data stored in multiple target nodes, we can also randomly generate a different salt value each time when verifying the integrity of the stored data of each target node, and Different data summaries are generated based on these different salt values, and the integrity of the stored data stored by different target nodes is verified according to the different data summaries to ensure the security and privacy of the verification process.

S103: Receive a second data summary sent by the target node; the second data summary is generated by the target node according to the salt value and currently stored data corresponding to the source data.

After receiving the salt value sent by the terminal of the data owner, the target node generates a second data summary based on the current stored data corresponding to the source data and the received salt value, and sends the data summary to the data owner for processing terminal.

Specifically, in the process of generating the second data summary, the target node may first add the salt value to the stored storage data to obtain the target data, and then generate the data summary according to the target data. The way to generate the data digest can be through the message digest algorithm. The main feature is that the encryption process does not require a key, and the encrypted data cannot be decrypted. Only the input of the same plaintext data through the same message digest algorithm can get the same ciphertext. . The message digest algorithm has no key management and distribution problems and is suitable for use on distributed networks. Because the workload of encryption calculation is quite huge, the previous algorithm is usually only used for encryption when the amount of data is limited. For example, the password of the computer is encrypted with an irreversible encryption algorithm.

S104: Compare the first data summary with the second data summary, and verify whether the stored data stored by the target node is complete according to the comparison result.

After generating the first data summary and the second data summary, the first data summary and the second data summary are compared to obtain a comparison result, and the stored data stored in the target node is verified based on the comparison result.

Specifically, in the process of comparing the first data digest and the second data digest, if the first data digest and the second data digest are the same, it is determined that the storage data currently stored by the target node is complete; If the second data summary is different, it is determined that the storage data currently stored by the target node is incomplete or tampered.

In the above solution, a salt value is randomly generated, and a first data summary is generated based on the salt value and the source data held by the data owner; the salt value is sent to a target node; the target node stores the source A node of data; receiving a second data summary sent by the target node; the second data summary is generated by the target node according to the salt value and currently stored data corresponding to the source data; the first The data summary is compared with the second data summary, and based on the comparison result, it is verified whether the stored data stored by the target node is complete. By adding salinity to the original data and stored data and performing data summarization, the reliability of data integrity verification is ensured, and the security and integrity of the stored data of P2P nodes are improved.

Referring to FIG. 2, FIG. 2 is a flowchart of a salt value-based data possession verification method provided in Embodiment 2 of the present application. In this embodiment, the execution subject of the data possession verification method based on the salt value is a terminal. Terminals include but are not limited to mobile terminals such as smart phones, tablet computers, and wearable devices, and may also be desktop computers. As shown in the figure, the salt value-based data possession verification method may include the following steps:

S201: Generate a salt value randomly according to the hash function algorithm.

The salinity value in this scheme is randomly generated by the system, and only the system knows it. In this way, even if two nodes store the same data, because the system generates different salinity values for them, their hash values are also different. Even if a hacker can find a user with a specific password through his own password and the hash value generated by himself, this chance is too small. When generating salt values, if the salt value is too short, the attacker can construct a lookup table containing all possible salt values. Exemplarily, if a salt value contains only 3 American Standard Code for Information Interchange (ASCII) characters, there are 95*95*95=857375 possibilities. This looks a lot, but if only 1MB of the most common password is included for each salt lookup table, then only a total of 837GB of storage space is required. Similarly, the username should not be used as a salt value. Although user names are unique in a website, they are predictable and are often used repeatedly in other services. An attacker can build a lookup table for common usernames and then attack the hash of the username salt.

In this embodiment, in order to prevent an attacker from constructing a lookup table containing all possible salt values, the salt value must be sufficiently long. The salt value is a randomly generated set of strings, which can include random upper and lower case letters, numbers, and characters. The number of digits can be different according to requirements. Preferably, a salt value equal to the string output by the hash function can be used. For example, the output of the Secure Hash Algorithm (SHA) is a string of 256 bits, then the salt value should also be at least 32 random byte.

S202: Combine the salt value with the source data held by the data owner to obtain target data.

Some storage node databases manage user IDs and passwords. Passwords exist in encrypted form such as MD5, but sometimes the database may be leaked and the data digest is obtained by the attacker. If the password corresponding to this data digest is a weak password, the hacker You can use this hash function HASH brute force cracking to obtain the IDs and passwords of other users and destroy the confidentiality of the data. By adding salt value, that is, salinization, this attack method can be well prevented. The salt value is a set of random character strings. The hash algorithm is inserted after the password is inserted, so that even if the password is the same, the data digest generated after inserting different salt values is also different. Due to the irreversibility of MD5, I want to reverse Cracking MD5 is also very time-consuming.

In order to strengthen the security of MD5, a new algorithm is added to add salt value. The salt value is a randomly generated set of character strings, which can include random upper and lower case letters, numbers, and characters. Similarly, the final ciphertext produced using different salting values is different. We can get the target data by combining the salt value with the source data held by the data owner. Among them, the specific combination method can be to add the salt value to the front or back of the source data, or to disassemble the salt value to obtain a piece of data, and add these data to the source data randomly. Get the target data.

S203: Generate a first data summary according to the target data.

After determining the target data composed of the salt value and the source data held by the data owner, a first data summary is generated according to the target data.

Further, step S203 may specifically include steps S2031 to S2033:

S2031: Convert the target data into a bit string.

In the data digest algorithm, the message is generally treated as a bit string. The smallest unit is called a bit, 8 bits form a byte, and two bytes form a word. Exemplarily, the string "abc" is converted into a bit string of 01100001 01100010 01100011, and the string converted into a hexadecimal string is 0x616263. Because the data digest algorithm only accepts bits as input, the target data must be converted to a bit string before calculation. Exemplary, for example, to generate a message digest for the character string "abc", ‘a’=97, ‘b’=98, ‘c’=99, first converted to a 24-bit character string: 01100001 01100010 01100011.

S2032: Perform bit complement processing on the bit string to obtain a string with a preset number of digits, and add a character representing the length of the bit string to the string with a preset number of digits to obtain a target character string.

After the message is filled, the length of the message is added at the end, and the length of the original message is added to the back of the message that has been filled. Specifies the use of 128-bit data to represent the length of the original message. In this way, the length of the processed message becomes a multiple of 1024.

In the data digest algorithm, the message must be complemented so that the remainder after the modulus is modulo 512 is 448, that is, the remainder after the complemented message length is divided by 512 is 448. When complementing the message, first add a 1 to the back, and if it does not meet the requirements, then add 0 until the modulus remainder of 512 is 448. This means that at least one bit is filled, and the original message digits are 512n+447, at most 512 bits, and the original message digits are 512n+448.

Exemplarily, taking the previous "abc" as an example to show the process of bit complementation: the original information is 01100001 01100010 01100011; the first step of complementing, first fill one 1: 01100001 01100010 01100011 1; what can be determined is that if a byte is used to represent a character, after complementing 1, the condition will definitely not be met, and the supplement needs to continue. In the second step of padding, zeros are added until the total length modulo 512 is 448. Here, 423 0s are filled to make the total length 448; the data after the padding is converted to hexadecimal. As can be seen from the hexadecimal data, we can also directly use the hexadecimal method to fill in bits. We first fill in 80 to see if the length meets the 64 and the result is 56. If it is not satisfied, continue to fill in 0. You can get a string of preset digits.

After obtaining the character string of the preset number of digits, add a character representing the length of the character string to the character string of the preset number of digits to obtain the target character string. In this step, the original message, that is, the length of the binary digits before the complement operation is appended to the already complemented message. A 64-bit data is usually used to represent the length of the original message. If the message length is not greater than 2^64, then the first word is 0. Then, the entire message is split into 512-bit data blocks M1, M2, ..., Mi, ..., Mn, and each data block Mi (1≤i≤n) is processed separately to obtain a message digest.

S2033: Process the target character string according to a digest function to obtain the first data digest.

The data digest algorithm of this solution includes 80 64-bit constants, K0, K1, K2, ..., K79, where these constants are obtained by cube the first 80 prime numbers and take the first 64 of the fractional part Bit, used to eliminate the statistical law in the data during subsequent message digest calculation. Using 6 logic functions, each function operates on 64-bit integers x, y, z, and produces 64-bit data as the result output after calculation.

When the message is calculated, the initialization operation needs to be performed first. Among them, the eight 64-bit data is used as the algorithm initialization vector, which is the original input of the digest calculation, and is marked as H ₀ , H ₁ , H ₂ , ..., H ₇ . Nine 64-bit spaces are used as intermediate variables during iteration, marked as A, B, C, D, E, F, G, H, I. Among them, the initial value of H ₀ , H ₁ , H ₂ , ..., H ₇ is a fixed value, and the value is the first 8 prime numbers whose squared fractional part is converted into the first 64 bits of binary. The 512-bit plaintext is divided into 16 32-bit long packets, denoted as M ₀ , M ₁ , M ₂ , ..., M ₁₀ ..., M ₁₅ , and the packet is expanded to become 80 32-bit data blocks. Assign values to buffers A, B, C, D, E, F, G, H, let A=H ₀ , B=H ₁ , C=H ₂ , D=H ₃ , E=H ₄ , F=H ₅ , G=H ₆ , I=H ₇ , and then iteratively calculate Wt (0≤t≤79) obtained by the expansion operation to obtain. After that, let H ₀ , H ₁ , H ₂ , ..., H _{7 be added} to At, Bt, Ct, Dt, Et, Ft, Gt, It respectively, and the result is stored in H ₀ , H ₁ , H ₂ , ..., In H ₇ , the calculation of the following 1024-bit message is used until the calculation of the last message block is completed, and the final 512-bit data result is the message digest calculated from the original message.

In the integrity verification of the stored data of P2P nodes with salinity value, the role of salinity value is very important. The system randomly generates a salinity value for the storage node and combines it with the data stored by the storage node, so that The storage data is highly random. Even if the storage node provides a data summary of the original data, the data summary generated by the storage node based on the storage data and the salinity value is also different due to the difference in the salinity value randomly generated by the system. In this way, the data holder can verify the integrity of the data stored by the storage node through the randomly generated salinity value, and improve the reliability of the verification process and verification results.

S204: Send the salt value to a target node; the target node is a node that stores the source data.

In this embodiment, S204 is implemented in exactly the same way as S102 in the embodiment corresponding to FIG. 1. For details, reference may be made to the relevant description of S102 in the embodiment corresponding to FIG. 1, and details are not described herein again.

S205: Receive a second data summary sent by the target node; the second data summary is generated by the target node according to the salt value and currently stored data corresponding to the source data.

In this solution, corresponding to the challenger, the P2P node that stores the source data is the target node, that is, the challenger. The challenger can detect the completeness of the data stored by the challenger at any time by sending the same salinity value to the target node. After receiving the salinity value, the target node according to the stored data and The second data summary calculated from the salinity value.

S206: Compare the first data summary with the second data summary, and verify whether the stored data stored by the target node is complete according to the comparison result.

After the first data summary and the second data summary are obtained, the two summaries are compared. If the two data summaries are the same, the data stored in the target node is determined to be complete. If the two data summaries are different, the target node is summarized. Of data is incomplete or has been tampered with. Further, when the first data summary and the second data summary are different, you can further directly view the data in the node, or you can directly replace the source data with the corresponding data in the node.

Further, if the first data digest is different from the second data digest, it is determined that the storage data currently stored by the target node is incomplete or tampered, and then may further include steps S2061 to S2062:

S2061: Obtain the currently stored storage data of the target node, and determine the reason for the change of the second data summary according to the storage data, and process the target node according to the cause of the change of the second data summary .

After comparing the first data digest and the second data digest, if the first data digest and the second data digest are different, it is determined that the storage data currently stored by the target node is incomplete or tampered. In this case, the storage data currently stored in the target node may be obtained, and the reason for the change in the second data summary may be determined according to the storage data. Among them, the reasons for the change may include, but are not limited to, malicious deletion or modification of the storage node, failure of the storage node, such as hard disk damage, downtime, etc.

According to the reason for the second data summary change of the target node, the target node is processed accordingly. Exemplarily, when the target node changes the second data summary through malicious deletion or modification, the data stored in the target node may be deleted, and the target node will not be enabled to store data in the future; if the target node is because If the change occurs in the second data summary caused by a hard disk damage or a downtime, after the operation of the target node returns to normal, the stored data may be sent to the target node again for storage.

S2062: Replace the stored data stored in the target node with the source data.

In parallel with step S2061, in step S2062, the source node can directly replace the currently stored storage data of the target node, continue to use the target node and the stored data stored in it, and can also add a series of security mechanisms, such as setting the target node The processing authority for the stored data prevents the target node from deleting or modifying the stored data, thereby ensuring the security and integrity of the stored data.

In the above solution, a salt value is randomly generated according to a hash function algorithm; the salt value is combined with the source data held by the data owner to obtain target data; and a first data summary is generated according to the target data. Randomly generate a salt value, and generate a first data summary based on the salt value and the source data held by the data owner; send the salt value to a target node; the target node is a node that stores the source data; Receiving a second data summary sent by the target node; the second data summary is generated by the target node according to the salt value and currently stored data corresponding to the source data; Compare the second data summary, and verify whether the stored data stored by the target node is complete according to the comparison result. By adding salinity to the original data and the stored data and performing a data summary, due to the different salt values randomly generated by the system, the data summary is also accompanied by a certain randomness, and the storage node cannot retain the data summary of the original data, ensuring the data The reliability of integrity verification improves the security and integrity of data stored by P2P nodes.

Referring to FIG. 3, FIG. 3 is a schematic diagram of a terminal device provided in Embodiment 3 of the present application. Each unit included in the terminal device is used to execute each step in the embodiments corresponding to FIG. 1 to FIG. 2. For details, please refer to the related descriptions in the corresponding embodiments of FIG. 1 to FIG. 2. For ease of explanation, only parts related to this embodiment are shown. The terminal device 300 of this embodiment includes:

The first summary unit 301 is configured to randomly generate a salt value, and generate a first data summary according to the salt value and the source data held by the data owner;

The sending unit 302 is configured to send the salt value to a target node; the target node is a node that stores the source data;

The second summary unit 303 is configured to receive a second data summary sent by the target node; the second data summary is generated by the target node according to the salt value and currently stored data corresponding to the source data;

The verification unit 304 is configured to compare the first data digest with the second data digest, and verify whether the stored data stored by the target node is complete according to the comparison result.

Further, the first summary unit 301 may include:

The salt value generating unit is used to randomly generate a salt value according to the hash function algorithm;

The data combining unit is used to combine the salt value with the source data held by the data owner to obtain target data;

The first summary generating unit is configured to generate a first data summary based on the target data.

Further, the first summary generating unit may include:

A character conversion unit for converting the target data into a bit string;

A bit complementing unit, used to perform bit complement processing on the bit character string to obtain a character string with a preset number of digits, and adding characters representing the length of the bit character string to the character string with a preset number of digits To get the target string;

The first generating unit is configured to process the target character string according to a summary function to obtain the first data summary.

Further, the verification unit 304 may include:

A comparison unit, configured to compare the first data summary with the second data summary;

A first determining unit, configured to determine that the stored data currently stored by the target node is complete if the first data digest and the second data digest are the same;

The second determining unit is configured to determine that the stored data currently stored by the target node is incomplete or tampered if the first data digest and the second data digest are different.

Further, the terminal device may include:

A processing unit, configured to obtain the stored data currently stored by the target node, and determine the cause of the change in the second data summary according to the stored data, and to the target according to the cause of the change in the second data summary Node for processing; or

A data replacement unit is used to replace the stored data stored in the target node with the source data.

4 is a schematic diagram of a terminal device provided in Embodiment 4 of the present application. As shown in FIG. 4, the terminal device 4 of this embodiment includes: a processor 40, a memory 41, and computer-readable instructions 42 stored in the memory 41 and executable on the processor 40. When the processor 40 executes the computer-readable instructions 42, the steps in the above embodiments of the salt value-based data possession verification method are implemented, for example, steps 101 to 104 shown in FIG. 1. Alternatively, when the processor 40 executes the computer-readable instructions 42, the functions of each module/unit in the foregoing device embodiments are realized, for example, the functions of the units 301 to 304 shown in FIG. 3.

Exemplarily, the computer-readable instructions 42 may be divided into one or more modules/units, the one or more modules/units are stored in the memory 41, and executed by the processor 40, To complete this application. The one or more modules/units may be a series of computer-readable instruction instruction segments capable of performing specific functions, and the instruction segments are used to describe the execution process of the computer-readable instructions 42 in the terminal device 4.

The terminal device 4 may be a computing device such as a desktop computer, a notebook, a palmtop computer and a cloud server. The terminal device may include, but is not limited to, the processor 40 and the memory 41. Those skilled in the art may understand that FIG. 4 is only an example of the terminal device 4 and does not constitute a limitation on the terminal device 4, and may include more or less components than the illustration, or a combination of certain components or different components. For example, the terminal device may further include an input and output device, a network access device, a bus, and the like.

The processor 40 may be a central processing unit (Central Processing Unit (CPU), can also be other general-purpose processors, digital signal processors (Digital Signal Processor, DSP), application-specific integrated circuits (Application Specific Integrated Circuit (ASIC), ready-made programmable gate array (Field-Programmable Gate Array, FPGA) or other programmable logic devices, discrete gates or transistor logic devices, discrete hardware components, etc. The general-purpose processor may be a microprocessor or the processor may be any conventional processor or the like.

The memory 41 may be an internal storage unit of the terminal device 4, such as a hard disk or a memory of the terminal device 4. The memory 41 may also be an external storage device of the terminal device 4, such as a plug-in hard disk equipped on the terminal device 4, a smart memory card (Smart Media Card, SMC), and a secure digital (SD) Cards, flash cards (Flash Card, FC), etc. Further, the memory 41 may include both an internal storage unit of the terminal device 4 and an external storage device. The memory 41 is used to store the computer-readable instructions and other programs and data required by the terminal device. The memory 41 can also be used to temporarily store data that has been or will be output.

Those skilled in the art can clearly understand that, for convenience and conciseness of description, only the above-mentioned division of each functional unit and module is used as an example for illustration. In practical applications, the above-mentioned functions may be allocated by different functional units, Module completion means that the internal structure of the device is divided into different functional units or modules to complete all or part of the functions described above. The functional units and modules in the embodiments may be integrated into one processing unit, or each unit may exist alone physically, or two or more units may be integrated into one unit. The above integrated unit may use hardware It can also be implemented in the form of software functional units. In addition, the specific names of the functional units and modules are only for the purpose of distinguishing each other, and are not intended to limit the protection scope of the present application. For the specific working processes of the units and modules in the above system, reference may be made to the corresponding processes in the foregoing method embodiments, which will not be repeated here.

In the above embodiments, the description of each embodiment has its own emphasis. For a part that is not detailed or recorded in an embodiment, you can refer to the related descriptions of other embodiments.

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 may be distributed on multiple network units. Some or all of the units may be selected according to actual needs to achieve the purpose of the solution of this embodiment.

If the integrated module/unit is implemented in the form of a software functional unit and sold or used as an independent product, it may be stored in a computer-readable storage medium. Based on this understanding, this application implements all or part of the processes in the methods of the above embodiments, and can also be completed by instructing relevant hardware through computer-readable instructions, which can be stored in a computer non-volatile Readable storage medium.

A person of ordinary skill in the art may understand that all or part of the process in the method of the foregoing embodiments may be completed by instructing relevant hardware through computer-readable instructions, and the computer-readable instructions may be stored in a computer non-volatile In a readable storage medium, when the computer-readable instructions are executed, they may include the processes of the foregoing method embodiments. Wherein, any reference to the memory, storage, database or other media used in the embodiments provided in this application may include non-volatile and/or volatile memory. Non-volatile memory may include read-only memory (ROM), programmable ROM (PROM), electrically programmable ROM (EPROM), electrically erasable programmable ROM (EEPROM), or flash memory. Volatile memory can include random access memory (RAM) or external cache memory. By way of illustration and not limitation, RAM is available in many forms, such as static RAM (SRAM), dynamic RAM (DRAM), synchronous DRAM (SDRAM), double data rate SDRAM (DDRSDRAM), enhanced SDRAM (ESDRAM), synchronous chain (Synchlink) DRAM (SLDRAM), memory bus (Rambus) direct RAM (RDRAM), direct memory bus dynamic RAM (DRDRAM), and memory bus dynamic RAM (RDRAM), etc.

The above-mentioned embodiments are only used to illustrate the technical solutions of the present application, not to limit them; although the present application has been described in detail with reference to the foregoing embodiments, those of ordinary skill in the art should understand that they can still implement the foregoing The technical solutions described in the examples are modified, or some of the technical features are equivalently replaced; and these modifications or replacements do not deviate from the spirit and scope of the technical solutions of the embodiments of the present application. Within the scope of protection of this application.

Claims

A method for verifying data possession based on salt value, which includes:

Randomly generate a salt value, and generate a first data summary based on the salt value and the source data held by the data owner;

Sending the salt value to a target node; the target node is a node that stores the source data;

Receiving a second data summary sent by the target node; the second data summary is generated by the target node according to the salt value and currently stored data corresponding to the source data;

Comparing the first data summary with the second data summary, and verifying whether the stored data stored by the target node is complete according to the comparison result.
The method for verifying data possession based on salt value according to claim 1, wherein the salt value is randomly generated, and the first data is generated according to the salt value and the source data held by the data owner Summary, including:

Randomly generate a salt value according to the hash function algorithm;

Combine the salt value with the source data held by the data owner to obtain the target data;

Generate a first data summary based on the target data.
The method for verifying data possession based on salt value according to claim 2, wherein the generating the first data summary according to the target data includes:

Convert the target data into a bit string;

Perform bit complement processing on the bit string to obtain a string with a preset number of digits, and add a character representing the length of the bit string to the string with a preset number of digits to obtain a target string;

The target character string is processed according to a digest function to obtain the first data digest.
The method for verifying data possession based on salt value according to any one of claims 1 to 3, wherein the first data summary is compared with the second data summary, and the comparison result is based on Verifying that the stored data stored by the target node is complete, including:

Compare the first data summary with the second data summary;

If the first data digest is the same as the second data digest, it is determined that the stored data currently stored by the target node is complete;

If the first data digest is different from the second data digest, it is determined that the stored data currently stored by the target node is incomplete or tampered.
The method for verifying data possession based on a salt value according to claim 4, wherein if the first data digest is different from the second data digest, it is determined that the target node currently stores After the stored data is incomplete or tampered, it also includes:

Acquiring stored data currently stored by the target node, and determining the reason for the change in the second data digest according to the stored data, and processing the target node according to the reason for the change in the second data digest; or

Replacing the stored data stored in the target node with the source data.
A terminal device, characterized in that it includes a memory and a processor, and the memory stores computer-readable instructions executable on the processor, wherein the processor executes the computer-readable instructions , The following steps are implemented:

Randomly generate a salt value, and generate a first data summary based on the salt value and the source data held by the data owner;

Sending the salt value to a target node; the target node is a node that stores the source data;

Receiving a second data summary sent by the target node; the second data summary is generated by the target node according to the salt value and currently stored data corresponding to the source data;

Comparing the first data summary with the second data summary, and verifying whether the stored data stored by the target node is complete according to the comparison result.
The terminal device according to claim 6, wherein the randomly generating a salt value, and generating the first data summary according to the salt value and the source data held by the data owner includes:

Randomly generate a salt value according to the hash function algorithm;

Combine the salt value with the source data held by the data owner to obtain the target data;

Generate a first data summary based on the target data.
The terminal device according to claim 7, wherein the generating the first data summary according to the target data includes:

Convert the target data into a bit string;

Perform bit complement processing on the bit string to obtain a string with a preset number of digits, and add a character representing the length of the bit string to the string with a preset number of digits to obtain a target string;

The target character string is processed according to a digest function to obtain the first data digest.
The terminal device according to any one of claims 6-8, wherein the first data summary is compared with the second data summary, and the stored result of the target node is verified according to the comparison result Whether the stored data is complete, including:

Compare the first data summary with the second data summary;

If the first data digest is the same as the second data digest, it is determined that the stored data currently stored by the target node is complete;

If the first data digest is different from the second data digest, it is determined that the stored data currently stored by the target node is incomplete or tampered.
The terminal device according to claim 9, wherein if the first data digest is different from the second data digest, it is determined that the stored data currently stored by the target node is incomplete or After tampering, it also includes:

Acquiring stored data currently stored by the target node, and determining the reason for the change in the second data digest according to the stored data, and processing the target node according to the reason for the change in the second data digest; or

Replacing the stored data stored in the target node with the source data.
A terminal device is characterized by comprising:

A first summary unit for randomly generating a salt value, and generating a first data summary according to the salt value and the source data held by the data owner;

A sending unit, configured to send the salt value to a target node; the target node is a node that stores the source data;

A second summary unit, configured to receive a second data summary sent by the target node; the second data summary is generated by the target node according to the salt value and currently stored data corresponding to the source data;

The verification unit is configured to compare the first data digest with the second data digest, and verify whether the stored data stored by the target node is complete according to the comparison result.
The terminal device according to claim 11, wherein the first summary unit comprises:

The salt value generating unit is used to randomly generate a salt value according to the hash function algorithm;

The data combining unit is used to combine the salt value with the source data held by the data owner to obtain target data;

The first summary generating unit is configured to generate a first data summary based on the target data.
The terminal device according to claim 12, wherein the first digest generating unit includes:

A character conversion unit for converting the target data into a bit string;

A bit complementing unit, used to perform bit complement processing on the bit character string to obtain a character string with a preset number of digits, and adding characters representing the length of the bit character string to the character string with a preset number of digits To get the target string;

The first generating unit is configured to process the target character string according to a summary function to obtain the first data summary.
The terminal device according to any one of claims 11 to 13, wherein the verification unit comprises:

A comparison unit, configured to compare the first data summary with the second data summary;

A first determining unit, configured to determine that the stored data currently stored by the target node is complete if the first data digest and the second data digest are the same;

The second determining unit is configured to determine that the stored data currently stored by the target node is incomplete or tampered if the first data digest and the second data digest are different.
The terminal device according to claim 14, further comprising:

A processing unit, configured to obtain the stored data currently stored by the target node, and determine the cause of the change in the second data summary according to the stored data, and to the target according to the cause of the change in the second data summary Node for processing; or

A data replacement unit is used to replace the stored data stored in the target node with the source data.
A computer non-volatile readable storage medium, the computer non-volatile readable storage medium stores computer readable instructions, characterized in that, when the computer readable instructions are executed by a processor, the following steps are implemented:

Randomly generate a salt value, and generate a first data summary based on the salt value and the source data held by the data owner;

Sending the salt value to a target node; the target node is a node that stores the source data;

Receiving a second data summary sent by the target node; the second data summary is generated by the target node according to the salt value and currently stored data corresponding to the source data;

Comparing the first data summary with the second data summary, and verifying whether the stored data stored by the target node is complete according to the comparison result.
The computer non-volatile storage medium according to claim 16, wherein the random generation of a salt value, and the first data summary is generated according to the salt value and the source data held by the data owner ,include:

Randomly generate a salt value according to the hash function algorithm;

Combine the salt value with the source data held by the data owner to obtain the target data;

Generate a first data summary based on the target data.
The computer non-volatile readable storage medium of claim 17, wherein the generating the first data summary according to the target data includes:

Convert the target data into a bit string;

Perform bit complement processing on the bit string to obtain a string with a preset number of digits, and add a character representing the length of the bit string to the string with a preset number of digits to obtain a target string;

The target character string is processed according to a digest function to obtain the first data digest.
The computer non-volatile storage medium according to any one of claims 16 to 18, wherein the first data summary and the second data summary are compared and verified according to the comparison result Whether the stored data stored by the target node is complete includes:

Compare the first data summary with the second data summary;

If the first data digest is the same as the second data digest, it is determined that the stored data currently stored by the target node is complete;

If the first data digest is different from the second data digest, it is determined that the stored data currently stored by the target node is incomplete or tampered.
The computer non-volatile storage medium according to claim 19, wherein if the first data digest is different from the second data digest, it is determined that the target node currently stores After the stored data is incomplete or tampered, it also includes:

Acquiring stored data currently stored by the target node, and determining the reason for the change in the second data digest according to the stored data, and processing the target node according to the reason for the change in the second data digest; or

Replacing the stored data stored in the target node with the source data.