CN113536358B - Private data safe storage method based on blockchain - Google Patents

Abstract

The invention relates to the technical field of big data, in particular to a private data safe storage method based on a blockchain, which comprises the steps of constructing a plurality of storage nodes, generating a plurality of copies for each data line, wherein the number of the copies is matched with the storage nodes, and the copies are associated with numbers; generating a confusion value for each field of the data line, wherein the confusion value falls into the value range of the field true value; randomly dispersing the true values of the data line fields into a plurality of copies for storage, and filling the fields which are not allocated to the true values with confusion values; distributing the plurality of copies to a plurality of storage nodes for storage; the field and the field allowed length of the data line form a data structure; the storage block has an area for storing a number; when the private data is taken out from the storage node, the private key signature number is used for sending the private data to the storage node, and after the storage node is verified, a copy corresponding to the number is provided. The invention has the following substantial effects: the real data value is hidden, and the safety of long-time data storage is effectively improved.

Description

A secure storage method for private data based on blockchain

Technical field

The invention relates to the field of big data technology, and in particular to a secure storage method for privacy data based on blockchain.

Background technique

With the development of information technology, enterprises generate a large amount of data involving production materials and privacy during the production process. While the industry has responded to the most nefarious forms of data theft, many computer systems remain vulnerable at some level. Companies of some sizes still fail to adequately protect these systems, leaving huge holes in data privacy. These environments leverage real data to test applications and house some of the enterprise's most confidential or sensitive information, such as trade secrets, intellectual property, business-critical information, business partner information, or customer information, much of which is used infrequently. But it needs to be stored for a long time. How to store these private data reliably for a long time has become an important research topic in the industry.

For example, Chinese patent CN112968859A, published on June 15, 2021, is an encrypted storage system for work privacy data, which includes a data input module, a data encryption module, a data transmission module and a data storage module. The data input module is used for identity verification. The user inputs the work privacy data and sends the work privacy data to the data encryption module; the data encryption module is used to encrypt the work privacy data using a symmetric encryption key to obtain the first encrypted data, and is used to use the data storage module The public key encrypts the symmetric encryption key to obtain the second encrypted data, and transmits the first encrypted data and the second encrypted data to the data transmission module; the data transmission module is used to send the first encrypted data and the second encrypted data to the data Storage module; the data storage module is used to receive and store the first encrypted data and the second encrypted data. Although its technical solution achieves encrypted storage and transmission of work privacy data. But it cannot solve the problem of leakage risk during storage.

Contents of the invention

The technical problem to be solved by this invention is: the current technical problem of low security of private data storage. A blockchain-based secure storage method for private data is proposed. This method can effectively improve the security of private data storage.

In order to solve the above technical problems, the technical solution adopted by the present invention is: a secure storage method for private data based on blockchain, constructing several storage nodes, assigning numbers to the data rows of the private data, and extracting the hash values of the data rows. Associated number storage; generate several copies for each data row, the number of copies matches the storage node, and the associated number of copies; generate an obfuscated value for each field of the data row, and the obfuscated value falls within the range of the true value of the field ; Randomly disperse the real values of the data row fields to several copies for storage, and fill in the fields that are not assigned real values with confusing values; assign several copies to several storage nodes for storage; the fields of the data rows and the allowed length of the fields are composed of Data structure, the storage node has several storage areas opened up for each data structure on its storage medium, each storage area opens up several storage blocks, the length of the storage block matches the maximum occupied space of the data structure; so The storage block has an area for storing numbers. When the storage node receives the copy, it extracts the data structure of the copy, finds the corresponding storage area, and stores the copy and number in the first blank storage block. If the storage area When the block is full, a new storage area is opened; when the private data is taken out from the storage node, the private key signature number is used to send it to the storage node. After verification, the storage node provides a copy corresponding to the number.

Preferably, the storage node establishes an exchange table for each storage area. The exchange table records several exchange pairs. The exchange pairs record two binary sequences. After the copy is stored, the copy and the above are checked in binary form. Whether there is an aligned swap pair in the copy stored in a storage block. If there is, the field where the swap pair is located is swapped. When requesting private data, the storage node finds the storage block according to the number and checks backward to see if there is an aligned swap. If there is a pair, the next storage block will be used as the basis, and backwards check again to see if there is an aligned swap pair, and only the field position where the swap pair exists will be checked to see if there is an aligned swap pair, until no aligned swap pair is found at the check position or the storage is reached. The last storage block in the area will be checked to make a backup of all storage blocks that have aligned swap pairs. Starting from the last storage block, restore the fields where the aligned swap pairs are located in order, and add the contents of the previous storage block of the copy corresponding to the number. to the backup, and then based on the content in the restored copy, check upward to see if there is a swap pair aligned with the previous storage block. If it exists, the corresponding fields will be swapped in the backup, and a copy will be obtained after the swap.

Preferably, the method of generating a confusion value for each field of the data row includes: generating a confusion value for each non-numeric field of the data row, the confusion value falling within the true value range of the field, and converting the data row into The real value of the field is randomly allocated to several copies for storage, and the fields in the copies that are not assigned real values are filled with confusion values; several addends and a confusion value are generated for each numeric field of the data row, and the positive value of the addend is The negative attribute is consistent with the real value. The number of addends is less than the number of storage nodes minus 3. The number of addends is a preset value. The real value of the numeric field and several addends are allocated to several copies respectively. , the copies that are not assigned values are filled with obfuscated values; several copies are allocated to several storage nodes for storage.

Preferably, the method of generating a confusion value for each field of the data row includes: generating a confusion value for each non-numeric field of the data row, the confusion value falling within the true value range of the field, and converting the data row into The real value of the field is randomly allocated to several copies for storage, and the fields in the copies that are not assigned real values are filled with obfuscated values; each numeric field of the data row is split into several addends, and the number of addends is Matching the number of storage nodes, several addends of the numeric field are allocated to several copies respectively; several copies are allocated to several storage nodes for storage.

As a preferred method, the method of splitting the numeric field into several addends includes: randomly generating several addends, the sum of the several addends is equal to the value of the numeric field, and the number of positive and negative numbers in the several addends is the same. ; The storage node changes the value of the addend in the period T1, so that the absolute value of the addend increases the prediction step; in the period T2, it obtains copies from several storage nodes and restores the data rows; the corresponding copies of the data rows are obtained from several storage nodes. Delete the storage node; regenerate obfuscated values for non-numeric fields, generate addends for numeric fields, and store them again.

Preferably, non-numeric fields with limited value ranges are enumerated, and a value comparison table is made. The value comparison table is an associated surrogate number for the non-numeric field values, and the value comparison table is stored; The value of is replaced with the substitution number in the value comparison table, and the non-numeric field is converted into a numeric field; several addends and several confusion values are generated for the converted non-numeric field, and the addends are different from each other. The confusion value is different from the addend. The sum of the addends and confusion values matches the number of storage nodes. The addends and confusion values all fall into the value range of the non-numeric field after conversion. Several addends and confusion values Values are assigned to several copies, and several copies are assigned to several storage nodes.

Preferably, non-numeric fields with limited value ranges are enumerated, and a value comparison table is made. The value comparison table is an associated surrogate number for the non-numeric field values, and the value comparison table is stored; The value of is replaced with the substitution number in the value comparison table, and the non-numeric field is converted into a numeric field; several addends are generated for the converted non-numeric field, and the number of several addends is related to the number of storage nodes. Matching, allocating several addends to several copies, and allocating several copies to several storage nodes.

The substantial effect of the present invention is: by decentrally storing data and adding confusion values, the real data values are hidden. Even if the data of some storage nodes is leaked, the real values and the ciphertext of the real values will not be lost. Even if all the data is stored If the data of the node is leaked, the real value cannot be obtained directly due to the confusion of the value, which effectively improves the security of long-term data storage; further hiding the stored data by using exchange pairs in storage improves the security of private data; By converting non-numeric fields into numeric types and splitting them for storage, the effect of hiding private data is achieved.

Description of the drawings

Figure 1 is a schematic flowchart of a method for securely storing private data in Embodiment 1.

Figure 2 is a schematic flowchart of a method for storing private data in a storage node according to Embodiment 1.

Figure 3 is a schematic flow chart of a method for generating confusion values in Embodiment 1.

Figure 4 is a schematic flowchart of a method for storing non-numeric fields in Embodiment 1.

Figure 5 is a schematic flowchart of the method for generating confusion values in Embodiment 2.

Figure 6 is a schematic flowchart of a numerical field storage method in Embodiment 2.

Figure 7 is a schematic flowchart of a non-numeric field storage method in Embodiment 2.

Detailed ways

The specific implementation manner of the present invention will be further described in detail below through specific examples and in conjunction with the accompanying drawings.

Example 1:

A secure storage method for private data based on blockchain, please refer to Figure 1, including the following steps:

Step A01) Construct several storage nodes, assign numbers to the data rows of the private data, extract the hash values of the data rows and store them in association with the numbers;

Step A02) Generate several copies for each data row, the number of copies matches the storage node, and the copy association number;

Step A03) Generate an obfuscated value for each field of the data row, and the obfuscated value falls within the range of the true value of the field;

Step A04) Randomly disperse the real values of the data row fields to several copies for storage, and fill in the fields that are not assigned real values with obfuscated values;

Step A05) Allocate several copies to several storage nodes for storage;

Step A06) The fields and allowed lengths of the data rows form a data structure. The storage node opens up several storage areas for each data structure on its storage medium. Each storage area opens up several storage blocks. The length of the storage block is related to the data. Match the maximum space occupied by the structure;

Step A07) The storage block has an area for storing numbers. When the storage node receives the copy, it extracts the data structure of the copy, finds the corresponding storage area, and stores the copy and number in the first blank storage block. If the storage area If the block is full, a new storage area will be opened;

Step A08) When retrieving private data from the storage node, use the private key signature number to send it to the storage node. After verification, the storage node provides a copy corresponding to the number.

When the storage node stores private data, please refer to Figure 2 and perform the following steps:

Step B01) The storage node establishes an exchange table for each storage area. The exchange table records several exchange pairs. The exchange pair records two binary sequences; for example, the binary sequence "101011" and the binary sequence "101110" are used as a pair of exchange pairs, such as The binary sequence "101010" and the binary sequence "000111" are used as a pair of swap pairs. If there are aligned swap pairs in two adjacent storage blocks, they will be swapped. The length of the swap pair is determined according to the length of the storage block, so that there are 2-3 aligned swap pairs between the storage block and the previous storage block.

Step B02) After storing the copy, check in binary form whether there is an aligned swap pair between the copy and the copy stored in the previous storage block;

Step B03) If it exists, exchange the field where the exchange pair is located;

Step B04) When requesting private data, the storage node finds the storage block according to the number and checks backward to see if there is an aligned swap pair;

Step B05) If it exists, use the next storage block as the basis to check backward again whether there is an aligned swap pair, and only check whether there is an aligned swap pair at the field position where the swap pair exists;

Step B06) Until an unaligned swap pair at the check position is found or the last storage block of the storage area is reached;

Step B07) Make a backup of all storage blocks that are checked to have aligned swap pairs;

Step B08) Starting from the last storage block, restore the fields where the aligned swap pairs are located in sequence;

Step B09) Add the contents of the previous storage block of the copy corresponding to the number to the backup, and then based on the contents of the restored copy, check upward whether there is an aligned swap pair with the previous storage block;

Step B10) If it exists, exchange the corresponding fields in the backup, and obtain a copy after the exchange. As shown in Table 1, a storage block in a certain storage area stores several copies. The aligned swap pairs in adjacent copies are shown in the table. The results after the swap are shown in Table 2. After the swap, the two The content stored in each storage block has been destroyed, causing private data to be hidden. Private data and the ciphertext of private data are effectively protected. Perform restorable damage to data to protect private data that is used infrequently.

Table 1 Numbers and copies stored in the storage area

serial number copy B36A55DE 101011 010…0 101010 100…1101010100111001 B36A55DF 101110 000…0 000111 010…0100 101011 110111 B36A55E0 101010100…0110111111…1001 101110 101010 … B36A56D7 101100100…0010000110…1100001100001111

Table 2 The results of the storage area after swapping

serial number copy B36A55DE 101110 010…0 000111 100…1101010100111001 B36A55DF 101011 000…0 101010 010…0100 101110 110111 B36A55E0 101010100…0110111111…1001 101011 101010 … B36A56D7 101100100…0010000110…1100001100001111

Before submitting private data to the storage node, please refer to Figure 3. The method of generating an obfuscated value for each field of the data row includes: Step C11) Generating an obfuscated value for each non-numeric field of the data row. Obfuscated value Falling within the range of the true value of the field; Step C12) Randomly allocate the true value of the data row field to several copies for storage, and fill in the confusion value for the fields in the copies that are not assigned true values; Step C13) For the data row Each numerical field generates several addends and a confusion value. The positive and negative attributes of the addend are consistent with the real value. The number of addends is less than the number of storage nodes minus 3. The number of addends is the preset value; step C14) The real value of the numeric field and several addends are allocated to several copies respectively, and the copies that are not assigned values are filled with confusion values; Step C15) Allocate several copies to several storage nodes for storage.

Before submitting private data to the storage node, for non-numeric data with limited values, such as ethnicity, occupation, city of residence, etc., please refer to Figure 4, including: Step E11) List non-numeric fields with limited value ranges, Create a value comparison table. The value comparison table is the substitution number associated with the value of the non-numeric field, and the value comparison table is stored. Step E12) Replace the value of the non-numeric field with the substitution number in the value comparison table. Convert non-numeric fields into numeric fields; Step E13) Generate several addends and several confusion values for the converted non-numeric fields; Step E14) The addends are different from each other, the confusion values are different from the addends, and the addends Match the number of obfuscation values and the number of storage nodes, and the addends and obfuscation values fall into the value range of the converted non-numeric fields; Step E15) Allocate several addends and obfuscation values to several copies respectively, Allocate several copies to several storage nodes. The addends are different from each other, and the obfuscation value is also different from the addend. However, there are at least two copies that store the obfuscation numbers. Therefore, when you obtain the addends stored by all storage nodes, you will find that there are several copies with the same value. These copies What is stored is the obfuscated value, and the values of the remaining copies are added to obtain the true value.

The beneficial technical effects of this embodiment are: by decentrally storing data and adding confusion values, the real data values are hidden. Even if the data of some storage nodes is leaked, the real values and the ciphertext of the real values will not be lost. Even if all If the data of the storage node is leaked, the real value cannot be obtained directly due to the confusion of the value, which effectively improves the security of long-term data storage; further hiding the stored data by using exchange pairs in storage improves the security of private data. ; By converting non-numeric fields into numeric fields and splitting them for storage, the effect of hiding private data is achieved.

Example 2:

A secure storage method for private data based on blockchain. Based on Embodiment 1, this embodiment proposes specific improvements to the method of splitting real values. Please refer to Figure 5. In this embodiment, the method of generating a confusing value for each field of the data row includes: step C21) generating a confusing value for each non-numeric field of the data row, and the confusing value falls into the true value of the field. Within the value range; Step C22) Randomly allocate the true values of the fields in the data row to several copies for storage, and fill in the confusion values for the fields in the copies that are not assigned true values; Step C23) For each numeric field of the data row Split into several addends, and the number of addends matches the number of storage nodes; Step C24) Allocate several addends of the numeric field to several copies; Step C25) Allocate several copies to several storages Node storage.

Please refer to Figure 6. The method of splitting a numeric field into several addends includes: Step D01) Randomly generate several addends. The sum of the several addends is equal to the value of the numeric field. The positive value among the several addends is The number of numbers and negative numbers is the same; Step D02) The storage node changes the value of the addend in period T1, so that the absolute value of the addend increases the prediction step; Step D03) Requests copies from several storage nodes in period T2, and restores the data rows ; Step D04) Delete the corresponding copies of the data rows from several storage nodes; Step D05) Regenerate confusion values for non-numeric fields, generate addends for numeric fields, and store again.

For the processing of non-numeric fields in this embodiment, please refer to Figure 7, which includes: Step E21) List non-numeric fields with limited value ranges, and create a value comparison table. The value comparison table is the value of the non-numeric fields. Associate the substitution number and store the value comparison table; Step E22) Replace the value of the non-numeric field with the substitution number in the value comparison table, and convert the non-numeric field into a numerical field; Step E23) For the converted The non-numeric field generates several addends, and the number of the several addends matches the number of storage nodes; Step E24) Allocate the several addends to several copies, and allocate the several copies to several storage nodes. This embodiment can further hide the true value of private data and improve the security of private data storage.

The above embodiment is only a preferred solution of the present invention and does not limit the present invention in any form. There are other variations and modifications without exceeding the technical solutions described in the claims.

Claims (4)

1. A secure storage method for private data based on blockchain, characterized by: Construct several storage nodes, assign numbers to the data rows of private data, and extract the hash values of the data rows and store them in association with the numbers; Generate several copies for each data row, the number of copies matches the storage node, and the copy association number; Generate an obfuscated value for each field of the data row, and the obfuscated value falls within the range of the true value of the field; The real values of the data row fields are randomly distributed to several copies for storage, and fields that are not assigned real values are filled with confusing values; Allocate several copies to several storage nodes for storage; The fields and allowed lengths of the data rows constitute a data structure. The storage node has several storage areas for each data structure on its storage medium. Each storage area has several storage blocks. The length of the storage block is equal to The maximum space occupied by the data structure matches; The storage block has an area for storing numbers. When the storage node receives a copy, it extracts the data structure of the copy, finds the corresponding storage area, and stores the copy and number in the first blank storage block. If the storage area If the storage block is full, a new storage area will be opened; When retrieving private data from the storage node, use the private key signature number to send it to the storage node. After verification, the storage node provides a copy corresponding to the number; The storage node establishes an exchange table for each storage area. The exchange table records several exchange pairs. The exchange pairs record two binary sequences. After the copy is stored, the copy and the previous storage block are checked in binary form. Whether there is an aligned swap pair in the internally stored copy. If there is, the field where the swap pair is located is swapped. When requesting private data, the storage node finds the storage block according to the number and checks backward to see if there is an aligned swap pair. If If there is, then the next storage block is used as the basis, and backwards check again to see if there is an aligned swap pair, and only the field position where the swap pair exists is checked to see if there is an aligned swap pair, until it is found that there is no aligned swap pair at the check position or the last one of the storage area is reached. For storage blocks, make a backup of all storage blocks that are checked to have aligned swap pairs. Starting from the last storage block, restore the fields where the aligned swap pairs are located in order, and add the contents of the previous storage block of the copy with the corresponding number to the backup. , and then based on the content in the restored copy, check upward to see if there is a swap pair aligned with the previous storage block. If it exists, the corresponding fields will be swapped in the backup, and the copy will be obtained after the swap; The method of generating a confusion value for each field of the data row includes: generating a confusion value for each non-numeric field of the data row, the confusion value falling within the range of the true value of the field, and converting the true value of the field of the data row into Values are randomly allocated to several replicas for storage, and fields in the replicas that are not assigned real values are filled with obfuscated values; Split each numeric field of the data row into several addends, the number of the addends matches the number of storage nodes, and allocate the several addends of the numeric field to several copies respectively; Allocate several copies to several storage nodes for storage; Methods of splitting a numeric field into several addends include: randomly generating several addends, the sum of the several addends is equal to the value of the numeric field, and the number of positive and negative numbers in the several addends is the same; The storage node changes the value of the addend in period T1, so that the absolute value of the addend increases by the prediction step; Retrieve copies from several storage nodes at cycle T2 and restore the data rows; Delete the copies corresponding to the data rows from several storage nodes; Regenerate obfuscated values for non-numeric fields, generate addends for numeric fields, and store them again. 2. A secure storage method for private data based on blockchain, characterized by: Construct several storage nodes, assign numbers to the data rows of private data, and extract the hash values of the data rows and store them in association with the numbers; Generate several copies for each data row, the number of copies matches the storage node, and the copy association number; Generate an obfuscated value for each field of the data row, and the obfuscated value falls within the range of the true value of the field; The real values of the data row fields are randomly distributed to several copies for storage, and fields that are not assigned real values are filled with confusing values; Allocate several copies to several storage nodes for storage; The fields and allowed lengths of the data rows constitute a data structure. The storage node has several storage areas for each data structure on its storage medium. Each storage area has several storage blocks. The length of the storage block is equal to The maximum space occupied by the data structure matches; The storage block has an area for storing numbers. When the storage node receives a copy, it extracts the data structure of the copy, finds the corresponding storage area, and stores the copy and number in the first blank storage block. If the storage area If the storage block is full, a new storage area will be opened; When retrieving private data from the storage node, use the private key signature number to send it to the storage node. After verification, the storage node provides a copy corresponding to the number; The storage node establishes an exchange table for each storage area. The exchange table records several exchange pairs. The exchange pairs record two binary sequences. After the copy is stored, the copy and the previous storage block are checked in binary form. Whether there is an aligned swap pair in the internally stored copy. If there is, the field where the swap pair is located is swapped. When requesting private data, the storage node finds the storage block according to the number and checks backward to see if there is an aligned swap pair. If If there is, then the next storage block is used as the basis, and backwards check again to see if there is an aligned swap pair, and only the field position where the swap pair exists is checked to see if there is an aligned swap pair, until it is found that there is no aligned swap pair at the check position or the last one of the storage area is reached. For storage blocks, make a backup of all storage blocks that are checked to have aligned swap pairs. Starting from the last storage block, restore the fields where the aligned swap pairs are located in order, and add the contents of the previous storage block of the copy with the corresponding number to the backup. , and then based on the content in the restored copy, check upward to see if there is a swap pair aligned with the previous storage block. If it exists, the corresponding fields will be swapped in the backup, and the copy will be obtained after the swap; The method of generating a confusion value for each field of the data row includes: generating a confusion value for each non-numeric field of the data row, the confusion value falling within the range of the true value of the field, and converting the true value of the field of the data row into Values are randomly allocated to several replicas for storage, and fields in the replicas that are not assigned real values are filled with obfuscated values; Generate several addends and a confusion value for each numerical field of the data row. The positive and negative attributes of the addends are consistent with the real values. The number of addends is less than the number of storage nodes minus 3. The number of addends is As a default value, the real value of the numeric field and several addends are assigned to several copies respectively, and the copies that are not assigned values are filled with confusing values; Allocate several copies to several storage nodes for storage. 3. A blockchain-based secure storage method for private data according to claim 2, characterized by enumerating non-numeric fields with limited value ranges and making a value comparison table, and the value comparison table is Non-numeric field values are associated with substitution numbers, and the value comparison table is stored; Replace the value of the non-numeric field with the substitution number in the value comparison table, and convert the non-numeric field into a numeric field; Generate several addends and several confusion values for the converted non-numeric fields. The addends are different from each other. The confusion values are different from the addends. The sum of the number of addends and confusion values matches the number of storage nodes. The addends are different from each other. Both numbers and confusion values fall within the value range of non-numeric fields after conversion. Several addends and confusion values are assigned to several copies respectively, and several copies are assigned to several storage nodes. 4. A secure storage method for privacy data based on blockchain according to claim 2, characterized by enumerating non-numeric fields with limited value ranges and making a value comparison table, and the value comparison table is Non-numeric field values are associated with substitution numbers, and the value comparison table is stored; Replace the value of the non-numeric field with the substitution number in the value comparison table, and convert the non-numeric field into a numeric field; Generate several addends for the converted non-numeric fields. The number of the several addends matches the number of storage nodes. The several addends are assigned to several copies respectively, and the several copies are assigned to several storage nodes.