Financial user digital file encryption management system and method based on blockchain

Abstract

The present invention discloses a blockchain-based financial user digital file encryption management system and method, relating to the field of financial management technology. The encryption management system includes an exchange end, an on-chain encryption module, and a user contract module. The exchange end is used to extract the user's digital file information and store the user's financial assets. The on-chain encryption module is used to encrypt, split and distribute the user's digital file information using blockchain technology. The user contract module is used to set a smart contract that sends information to an inheritance address at a specified time, and the user reads the information through a private key. The exchange end includes a file entry module, an information sending module, and an account login module. The account login module is electrically connected to the file entry module and the information sending module. The present invention has the characteristic of solving the problem of legal inheritance.

Description

Technical Field

[0001] The present invention relates to the field of financial management technology, and in particular to a blockchain-based financial user digital file encryption management system and method. Background Art

[0002] Many users deposit large amounts of financial assets in exchanges, holding them in the form of stocks, futures or securities, but are unable to tell their families how they liquidate these assets because they are afraid that their family members will take the assets away without permission. However, in the event of a sudden death, it will be difficult for their family members to claim the financial assets they deserve from the exchange based on their inheritance rights without knowing the password, and the assets may be embezzled by the exchange.

[0003] While blockchain and its associated smart contract technology have gained traction in the financial sector due to their decentralized and tamper-proof nature, the legal inheritance of financial assets on exchanges has yet to be addressed using blockchain technology. Therefore, it is crucial to design a blockchain-based encrypted digital file management system and method for financial users to address this issue. Summary of the Invention

[0004] The purpose of the present invention is to provide a blockchain-based financial user digital file encryption management system and method to solve the problems raised in the above background technology.

[0005] In order to solve the above technical problems, the present invention provides the following technical solutions: a blockchain-based financial user digital file encryption management system, including an exchange end, an on-chain encryption module, and a user contract module. The exchange end is used to extract the user's digital file information and store the user's financial assets. The on-chain encryption module is used to use blockchain technology to encrypt, split and distribute the user's digital file information. The user contract module is used to set a smart contract that sends information to an inherited address at a specified time, and the user reads the information through a private key.

[0006] According to the above technical solution, the exchange end includes a file entry module, an information sending module, and an account login module. The account login module is electrically connected to the file entry module and the information sending module. The file entry module is used to enter the user's exchange account privacy information, and the information sending module is used to send the account privacy information to the blockchain. The account login module is used for users to log in to their exchange accounts and grant permissions to enter information and send information to the blockchain.

[0007] The on-chain encryption module includes an information encryption module, an information sharding module, an address management module, a distributed storage module, and a private key generation module. The information encryption module is electrically connected to the information sharding module, which is electrically connected to the address management module, which is electrically connected to the distributed storage module. The information encryption module encrypts user account privacy information, including exchange keys and asset certificates. The information sharding module shards the encrypted information into several copies to ensure that the leakage of a single address will not lead to the exposure of complete information. The address management module generates and manages multiple storage addresses controlled by the user. The distributed storage module is used to disperse the encrypted information to multiple storage addresses on the blockchain. The private key generation module is used to generate a private key for each storage address for the user to decrypt and obtain information read permission for the user to retain.

[0008] The user contract module includes a time setting module, a condition trigger module, a shard information transfer module, and an information reading module. The time setting module is electrically connected to the condition trigger module, the shard information transfer module is electrically connected to the address management module, and the information reading module is electrically connected to the private key generation module. The time setting module is used for the user to set the transfer time and the judgment time for not logging in. The condition trigger module is used to detect and determine whether the set time for shard information transfer has been reached, and send a final confirmation notification to the user. The shard information transfer module is used to transfer the shards in the storage address group to the inheritance address in sequence, decrypt and reorganize them into complete information. The information reading module is used to verify the user's authority to read the information in the inheritance address through the private key, and display the information to the user.

[0009] The blockchain-based method for encrypting and managing digital files of financial users includes the following steps:

[0010] S1. The user enters their account privacy information, such as keys and asset certificates, on the exchange side, obtains permissions through the account login module, and encrypts the information before sending it to the chain;

[0011] S2. The information is divided into multiple shards and distributed to multiple blockchain addresses. The information is written and stored separately through the distributed storage module. A unique private key is generated for each address for the user to keep, and an inheritance address is generated.

[0012] S3. The user sets two parameters: the future time point for asset transfer and the period for determining if the user has not logged in for a long period of time. The system continuously monitors whether the user has logged in within the set period and whether the set transfer time has been reached. Once the conditions are met, the system triggers the shard transfer logic, sequentially extracting shard data from multiple storage addresses and transferring it to the inheritance address, where it is merged and decrypted into complete account privacy information.

[0013] S4. Complete identity authentication through the retained inherited address private key, access and read the reorganized account information, and then obtain the user's asset control authority in the exchange.

[0014] According to the above technical solution, in S1, the specific steps of encrypting the information and sending it to the chain are:

[0015] S1-1. After a user logs in to an exchange account and grants permission, the exchange uses the AES-256-GCM symmetric encryption algorithm to generate a 256-bit AES key for the user's account privacy information. The AES key is then used to encapsulate and encrypt the account privacy information. The generated encryption result contains an encrypted information package consisting of the encrypted account privacy information, an initialization vector, and an integrity check tag. The encrypted information package is then stored locally on the exchange.

[0016] S1-2. The exchange uses an asymmetric encryption algorithm to generate an asymmetric key pair for the user locally, consisting of a public key and a private key. The private key is kept by the user. The Diffie-Hellman key exchange protocol is used to generate a shared key in conjunction with the public key. The shared key is used to encrypt and encapsulate the AES key, which is then uploaded to a specific blockchain address generated by hashing the public key.

[0017] S1-3. Users can exchange keys with the system's public key through their private key to calculate the same shared key, that is, decrypt the AES key through the private key, further decrypt the account's encrypted information package, access and modify the content in the encrypted information package, and update the exchange account's privacy information in real time.

[0018] According to the above technical solution, in S2, the information is written and stored respectively through the distributed storage module as follows:

[0019] S2-1, split the shared key into several fragments, denoted as ,in is the shard number. The more shards there are, the stronger the confidentiality of the shared key will be, but the cost of storage and reading will be greater. The specific calculation formula is: ,in is the user's asset amount, The on-chain gas fees required for storage, is the asset amount weight coefficient, is the gas fee weight coefficient on the chain;

[0020] S2-2. Based on the key pair consisting of the user's public key and private key, a series of sub-private keys and sub-addresses are generated according to the HD wallet path standard. The shared key information in each shard is sent to each sub-address in the prescribed order. The number of sub-private keys and sub-addresses is t+1. The user can read the shared key information in each sub-address through the sub-private key. The remaining sub-address that does not store the shared key information and its corresponding sub-private key are given to the user's family for safekeeping. This sub-address is the inherited address.

[0021] According to the above technical solution, in S3, the system triggers the shard transfer logic as follows:

[0022] S3-1. The user sets two time parameters, one of which is the future time point of asset transfer , and the second is the non-login period threshold Each time a user logs in, the off-chain monitoring engine will detect it, record the timestamp, and update the last activity time variable. , by continuously updating the current time ,like ,as well as , then it is judged that the transfer condition is met;

[0023] S3-2. The system freezes the data structure on the original storage sub-address to prevent simultaneous access or tampering. At the same time, it activates the receiving channel of the inherited address, transmits the shared key information of each sub-address to the inherited address in the set order, and merges the data of each shard.

[0024] According to the above technical solution, in S4, the specific method for completing identity authentication with the private key is:

[0025] After receiving the information at the inherited address, the user's family accesses the shared key through the inherited address, decrypts the AES key that was initially encapsulated and stored, and then logs in to the exchange end. By entering the AES key, they further decrypt the account privacy information in the encrypted information package, log in to the user's account by reading the account privacy information, and realize control over the financial assets in the account.

[0026] According to the above technical solution, in S1, if the assets deposited by the user on the exchange are encrypted assets that can be stored at an on-chain address, then the privacy information of the account is the private key corresponding to the user's encrypted asset at the exchange's on-chain address. When it is determined that the transfer condition in S3-1 is met, the system unlocks the private key corresponding to the on-chain address and directly transfers the encrypted assets stored by the user at the on-chain address to the inherited address.

[0027] Compared with the existing technology, the beneficial effects achieved by the present invention are as follows: the present invention encrypts the user's account privacy information in the exchange and stores it in multiple addresses on the blockchain. The combination order and the private key of the address are only known to the user himself, and an inheritance address is generated for family members to hold. The user sets a transfer time through the smart contract. When the transfer time arrives or when the user has not logged in for a long time, all addresses will transfer the account privacy information in order to the inheritance address. Family members can obtain the user's account privacy information by reading the information on the inheritance address with the private key and can take away the financial assets in the account. In this way, family members cannot take away the assets privately before the specified time, and can provide property protection for family members in the event of a sudden death due to an accident. BRIEF DESCRIPTION OF THE DRAWINGS

[0028] The accompanying drawings are used to provide a further understanding of the present invention and constitute a part of the specification. Together with the embodiments of the present invention, they are used to explain the present invention and do not constitute a limitation of the present invention. In the accompanying drawings:

[0029] Figure 1 It is a structural diagram of the encryption management system of the present invention. DETAILED DESCRIPTION

[0030] The following will clearly and completely describe the technical solutions in the embodiments of the present invention in conjunction with the accompanying drawings. Obviously, the described embodiments are only 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 making creative efforts are within the scope of protection of the present invention.

[0031] See also Figure 1 The present invention provides a technical solution: a blockchain-based financial user digital file encryption management system, including an exchange end, an on-chain encryption module, and a user contract module. The exchange end is used to extract the user's digital file information and store the user's financial assets. The on-chain encryption module is used to encrypt, split and distribute the user's digital file information using blockchain technology. The user contract module is used to set a smart contract that sends information to an inherited address at a specified time, and the user can read the information through a private key.

[0032] The exchange side includes a file entry module, an information sending module, and an account login module. The account login module is electrically connected to the file entry module and the information sending module. The file entry module is used to enter the user's exchange account privacy information. The information sending module is used to send the account privacy information to the blockchain. The account login module is used for users to log in to their exchange accounts and grant permissions to enter information and send information to the blockchain.

[0033] The on-chain encryption module includes an information encryption module, an information sharding module, an address management module, a distributed storage module, and a private key generation module. The information encryption module is electrically connected to the information sharding module, which is electrically connected to the address management module, which is electrically connected to the distributed storage module. The information encryption module encrypts user account privacy information, including exchange keys and asset certificates. The information sharding module shards the encrypted information into several copies to ensure that the leakage of a single address will not lead to the exposure of complete information. The address management module generates and manages multiple storage addresses controlled by the user. The distributed storage module is used to disperse the encrypted information to multiple storage addresses on the blockchain. The private key generation module is used to generate a private key for each storage address for the user to decrypt and obtain information reading permissions for retention;

[0034] The user contract module includes a time setting module, a condition trigger module, a shard information transfer module, and an information reading module. The time setting module is electrically connected to the condition trigger module, the shard information transfer module is electrically connected to the address management module, and the information reading module is electrically connected to the private key generation module. The time setting module is used by the user to set the transfer time and the judgment time for not logging in. The condition trigger module is used to detect and determine whether the set time for shard information transfer has been reached and send a final confirmation notification to the user. The shard information transfer module is used to transfer the shards in the storage address group to the inheritance address in sequence, decrypt and reassemble them into complete information. The information reading module is used to verify the user's permission to read the information in the inheritance address through the private key, and display the information to the user.

[0035] The blockchain-based method for encrypting and managing digital files of financial users includes the following steps:

[0036] S1. The user enters their account privacy information, such as keys and asset certificates, on the exchange side, obtains permissions through the account login module, and encrypts the information before sending it to the chain;

[0037] S2. The information is divided into multiple shards and distributed to multiple blockchain addresses. The information is written and stored separately through the distributed storage module. A unique private key is generated for each address for the user to keep, and an inheritance address is generated.

[0038] S3. The user sets two parameters: the future time point for asset transfer and the period for determining if the user has not logged in for a long period of time. The system continuously monitors whether the user has logged in within the set period and whether the set transfer time has been reached. Once the conditions are met, the system triggers the shard transfer logic, sequentially extracting shard data from multiple storage addresses and transferring it to the inheritance address, where it is merged and decrypted into complete account privacy information.

[0039] S4. Complete identity authentication through the inherited address private key, access and read the reorganized account information, and then obtain the user's asset control authority on the exchange;

[0040] In S1, the specific steps for encrypting information and sending it to the chain are:

[0041] S1-1. After a user logs in to an exchange account and grants permission, the exchange uses the AES-256-GCM symmetric encryption algorithm to generate a 256-bit AES key for the user's account privacy information. The AES key is then used to encapsulate and encrypt the account privacy information. The generated encryption result contains an encrypted information package consisting of the encrypted account privacy information, an initialization vector, and an integrity check tag. The encrypted information package is then stored locally on the exchange. The encrypted information package is always stored locally on the exchange and does not involve on-chain storage. This can maximize the protection of the user's private data from being leaked. Even if all on-chain addresses are made public, attackers still cannot obtain the user's original private data.

[0042] S1-2. The exchange uses an asymmetric encryption algorithm to generate an asymmetric key pair for the user locally, including a public key and a private key. The private key is kept by the user himself, and the Diffie-Hellman key exchange protocol is used to jointly generate a shared key with the public key. The shared key is used to encrypt and encapsulate the AES key, and the shared key is uploaded to a specific blockchain address generated by the public key hash. A combination of symmetric and asymmetric encryption is used. Even if an attacker obtains the shared key sharding information on the chain, he cannot reverse engineer the original AES key. He must then have the correct private key to decrypt it, which increases the difficulty of cracking. The blockchain (decentralized) and the exchange system (centralized) assume different encryption responsibilities, reducing the risk of single point failure.

[0043] S1-3. Users can exchange keys with the system's public key through private keys to calculate the same shared key, that is, decrypt the AES key through the private key, further decrypt the account's encrypted information package, access and modify the content of the encrypted information package, and update the exchange account's privacy information in real time; through the shared key, users can use their own private key to modify the account privacy data in the encrypted information package in real time, without having to go through lengthy reverse cracking steps to modify it, thereby improving the efficiency of information updating.

[0044] In S2, the information is written and stored through the distributed storage module as follows:

[0045] S2-1, split the shared key into several fragments, denoted as ,in is the shard number. The more shards there are, the stronger the confidentiality of the shared key will be, but the cost of storage and reading will be greater. The specific calculation formula is: ,in is the user's asset amount, The on-chain gas fees required for storage, is the asset amount weight coefficient, is the gas fee weight coefficient on the chain;

[0046] S2-2, based on the key pair consisting of the user's public key and private key, generate a series of sub-private keys and sub-addresses according to the HD wallet path standard, and send the shared key information in each shard to each sub-address in the prescribed order. The number of sub-private keys and sub-addresses is , users can read the shared key information in each sub-address through the sub-private key, and give the remaining sub-address that does not store the shared key information and its corresponding sub-private key to the user's family for safekeeping. This sub-address is the inherited address; each shard exists only in an independent sub-address and is independent of each other. Even if an attacker breaks into a sub-address, he cannot restore the complete key, which significantly enhances the anti-cracking ability.

[0047] In S3, the system triggers the shard transfer logic as follows:

[0048] S3-1. The user sets two time parameters, one of which is the future time point of asset transfer , and the second is the non-login period threshold Each time a user logs in, the off-chain monitoring engine will detect it, record the timestamp, and update the last activity time variable. , by continuously updating the current time ,like ,as well as , then it is judged that the transfer condition is met;

[0049] S3-2. The system freezes the data structure on the original storage sub-address to prevent simultaneous access or tampering, and at the same time activates the receiving channel of the inherited address, transmits the shared key information of each sub-address to the inherited address in the set order, and merges the data of each shard; the original sub-address is frozen when triggered and the inherited address is activated, effectively preventing replay attacks, double-spending attacks or malicious interference in the transfer process of on-chain data.

[0050] In S4, the specific method for private key to complete identity authentication is:

[0051] After receiving the information at the inherited address, the user's family accesses the shared key through the inherited address, decrypts the AES key that was initially encapsulated and stored, and then logs into the exchange. By entering the AES key, they further decrypt the account privacy information in the encrypted information package and log into the user's account by reading the account privacy information, thus achieving control over the financial assets in the account.

[0052] In S1, if the assets deposited by the user on the exchange are crypto assets that can be stored at an on-chain address, the user's account privacy information is the private key corresponding to the user's crypto asset at the exchange's on-chain address. When the transfer conditions in S3-1 are met, the system unlocks the private key corresponding to the on-chain address and directly transfers the user's crypto assets stored at the on-chain address to the inheritance address. When the financial asset is a crypto asset, asset inheritance occurs entirely on-chain, without the need for off-chain data reorganization or user interaction, in line with the automation principles of smart contracts.

[0053] This invention encrypts the user's account privacy information in the exchange and stores it in multiple addresses on the blockchain. The order of combination and the private key of the addresses are known only to the user himself, and an inheritance address is generated for family members to hold. The user sets a transfer time through the smart contract. When the transfer time arrives or when the user has not logged in for a long time, all addresses will transfer the account privacy information in sequence to the inheritance address. Family members can read the information on the inheritance address with the private key to obtain the user's account privacy information and take away the financial assets in the account. This method prevents family members from taking assets privately before the specified time, and can provide property protection for family members in the event of a sudden death due to an accident.

[0054] It should be noted that, in this document, relational terms such as first and second, etc., are used only to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply any actual relationship or order between these entities or operations. Moreover, the terms "comprises," "comprising," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or apparatus that includes a list of elements includes not only those elements but also other elements not explicitly listed, or elements inherent to such process, method, article, or apparatus.

[0055] Finally, it should be noted that the above descriptions are merely preferred embodiments of the present invention and are not intended to limit the present invention. Although the present invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art will be able to modify the technical solutions described in the aforementioned embodiments or substitute equivalents for some of the technical features. Any modifications, equivalent substitutions, and improvements made within the spirit and principles of the present invention shall be included within the scope of protection of the present invention.

Claims

1. A blockchain-based encrypted digital file management system for financial users, characterized by: The encryption management system includes an exchange terminal, an on-chain encryption module, and a user contract module; the exchange terminal is used to extract the user's digital archive information and store the user's financial assets; The on-chain encryption module is used to encrypt, split and distribute the user's digital archival information using blockchain technology; The exchange terminal includes a file entry module, an information sending module, and an account login module; the account login module is electrically connected to the file entry module and the information sending module; the file entry module is used to enter the user's exchange account private information; the information sending module is used to send the account private information to the blockchain; the account login module is used to log in to the user's exchange account and grant the user the authority to enter information and the authority to send information to the blockchain; The on-chain encryption module includes an information encryption module, an information sharding module, an address management module, a distributed storage module, and a private key generation module; the information encryption module is electrically connected to the information sharding module, which is in turn electrically connected to the address management module; the address management module is electrically connected to the distributed storage module, the information encryption module encrypts user account privacy information, including exchange keys and asset certificates, and the information sharding module shards the encrypted information into several copies to ensure that the leakage of a single address does not lead to the exposure of complete information, the address management module generates and manages multiple storage addresses controlled by the user, the distributed storage module is used to disperse the encrypted information to multiple storage addresses on the blockchain, and the private key generation module is used to generate a private key for each storage address for the user to decrypt and obtain information read permissions for retention by the user; The user contract module includes a time setting module, a condition trigger module, a shard information transfer module, and an information reading module; the time setting module is electrically connected to the condition trigger module, the shard information transfer module is electrically connected to the address management module, and the information reading module is electrically connected to the private key generation module; the time setting module is used for the user to set the transfer time and the judgment time for not logging in, the condition trigger module is used to detect and determine whether the set time for shard information transfer has been reached, and send a final confirmation notification to the user, the shard information transfer module is used to transfer the shards in the storage address group to the inheritance address in sequence, decrypt and reorganize them into complete information, and the information reading module is used to verify the user's family's authority to read the information in the inheritance address through the private key corresponding to the inheritance address, and display the information to the user's family.

2. A blockchain-based method for encrypting and managing digital files of financial users, characterized by: The following steps are involved: S1. The user enters their account privacy information, such as keys and asset certificates, on the exchange side, obtains permissions through the account login module, and encrypts the information before sending it to the chain; S2. The information is divided into multiple shards and distributed to multiple blockchain addresses. The information is written and stored separately through the distributed storage module. A unique private key is generated for each address for the user to keep, and an inheritance address is generated. S3. The user sets two parameters: the future time point for asset transfer and the period for determining if the user has not logged in for a long period of time. The system continuously monitors whether the user has logged in within the set period and whether the set transfer time has been reached. Once the conditions are met, the system triggers the shard transfer logic, sequentially extracting shard data from multiple storage addresses and transferring it to the inheritance address, where it is merged and decrypted into complete account privacy information. S4. The user's family completes identity authentication through the inherited address private key, accesses and reads the reorganized account information, and then obtains asset control rights in the exchange.

3. The blockchain-based financial user digital file encryption management method according to claim 2 is characterized by: In S1, the specific steps of encrypting the information and sending it to the chain are: S1-1. After a user logs in to an exchange account and grants permission, the exchange uses the AES-256-GCM symmetric encryption algorithm to generate a 256-bit AES key for the user's account privacy information. The AES key is then used to encapsulate and encrypt the account privacy information. The generated encryption result contains an encrypted information package consisting of the encrypted account privacy information, an initialization vector, and an integrity check tag. The encrypted information package is then stored locally on the exchange. S1-2. The exchange uses an asymmetric encryption algorithm to generate an asymmetric key pair for the user locally, consisting of a public key and a private key. The private key is kept by the user. The Diffie-Hellman key exchange protocol is used to generate a shared key in conjunction with the public key. The shared key is used to encrypt and encapsulate the AES key, which is then uploaded to a specific blockchain address generated by hashing the public key. S1-3. Users can exchange keys with the system's public key through their private key to calculate the same shared key, that is, decrypt the AES key through the private key, further decrypt the account's encrypted information package, access and modify the content in the encrypted information package, and update the exchange account's privacy information in real time.

4. The blockchain-based financial user digital file encryption management method according to claim 3 is characterized by: In S2, the information is written and stored respectively through the distributed storage module as follows: S2-1, split the shared key into several fragments, denoted as ,in is the shard number. The more shards there are, the stronger the confidentiality of the shared key will be, but the cost of storage and reading will be greater. The specific calculation formula is: ,in is the user's asset amount, The on-chain gas fees required for storage, is the asset amount weight coefficient, is the gas fee weight coefficient on the chain; S2-2, based on the key pair consisting of the user's public key and private key, generate a series of sub-private keys and sub-addresses according to the HD wallet path standard, and send the shared key information in each shard to each sub-address in the prescribed order. The number of sub-private keys and sub-addresses is , the user can read the shared key information in each sub-address through the sub-private key, and give the remaining sub-address that does not store the shared key information and its corresponding sub-private key to the user's family for safekeeping. This sub-address is the inherited address.

5. The blockchain-based financial user digital file encryption management method according to claim 4 is characterized by: In S3, the system triggers the shard transfer logic as follows: S3-1. The user sets two time parameters, one of which is the future time point of asset transfer , and the second is the non-login period threshold Each time a user logs in, the off-chain monitoring engine will detect it, record the timestamp, and update the last activity time variable. , by continuously updating the current time ,like ,as well as , then it is judged that the transfer condition is met; S3-2. The system freezes the data structure on the original storage sub-address to prevent simultaneous access or tampering. At the same time, it activates the receiving channel of the inherited address, transmits the shared key information of each sub-address to the inherited address in the set order, and merges the data of each shard.

6. The blockchain-based financial user digital file encryption management method according to claim 5 is characterized by: In S4, the specific method for completing identity authentication with a private key is: After receiving the information at the inherited address, the user's family accesses the shared key through the inherited address, decrypts the AES key that was initially encapsulated and stored, and then logs in to the exchange end. By entering the AES key, they further decrypt the account privacy information in the encrypted information package, log in to the user's account by reading the account privacy information, and realize control over the financial assets in the account.

7. The blockchain-based financial user digital file encryption management method according to claim 6 is characterized by: In S1, if the assets deposited by the user on the exchange are encrypted assets that can be stored at an on-chain address, then the privacy information of the account is the private key corresponding to the user's encrypted asset at the exchange's on-chain address. When it is determined that the transfer condition in S3-1 is met, the system unlocks the private key corresponding to the on-chain address and directly transfers the encrypted assets stored by the user at the on-chain address to the inherited address.

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