WO2018201797A1

WO2018201797A1 - Block chain-based distributed storage

Info

Publication number: WO2018201797A1
Application number: PCT/CN2018/078515
Authority: WO
Inventors: 程司雷
Original assignee: 上海点融信息科技有限责任公司
Priority date: 2017-05-03
Filing date: 2018-03-09
Publication date: 2018-11-08
Also published as: CN107273410A; CN107273410B

Abstract

Disclosed is a block chain-based distributed storage method. The method comprises: obtaining a file which needs to be stored; and generating a hash value and an index of the hash value for the file. The method also comprises: recording the hash value in a block chain network; and storing the file in a distributed network, wherein the file is located on the basis of the hash value in the distributed network. Therefore, tampering proofing and the distributed storage of the file can be realized through combining a block chain and a distributed file system, thereby solving the problem of the limited capacity of block chain nodes, and effectively ensuring the authenticity and the availability of the stored file.

Description

Blockchain-based distributed storage

Technical field

Embodiments of the present disclosure generally relate to the field of file storage technology, and more particularly to a blockchain based distributed storage method and apparatus.

Background technique

A blockchain is a decentralized storage and computational technique that generates persistent, unmodifiable records by superimposing encrypted blocks of data in chronological order and stores them in nodes of the blockchain network. This allows a reliable database to be maintained collectively in a decentralized manner. Each data block contains system data for a certain period of time, and a data fingerprint is generated to verify the validity of its information and to link to the next database block. Therefore, the blockchain has technical advantages in data tamper resistance, transparency, and decentralization.

Typically, Internet intermediaries use third-party digital signature companies to guarantee the authenticity of documents, such as electronic contracts. For example, parties involved in an electronic contract sign an electronic contract and then store the electronic contract in a storage device of a third-party digital signing company to ensure the authenticity (no tampering) and availability (backup) of the electronic contract. In the event of a dispute, a true and usable electronic contract can be obtained from a digitally signed company to ensure the legal validity of the electronic contract. In the process, it takes some time for a third-party digital signing company to obtain an electronic contract and pay for some certification and archiving fees.

Summary of the invention

In view of this, embodiments of the present disclosure propose a blockchain-based distributed storage method and apparatus. The embodiment of the present disclosure can realize the tamper-proof and distributed storage of files by combining the blockchain and the distributed file system, thereby solving the problem that the capacity of the blockchain node is limited, and effectively ensuring the stored files. Authenticity and usability.

According to a first aspect of the present disclosure, a blockchain-based distributed storage method is provided. The method includes obtaining a file to be stored and generating an index of the hash value and the hash value for the file. The method also includes recording the hash value in the blockchain network and storing the file in a distributed network, wherein the file is located based on the hash value in the distributed network.

According to a second aspect of the present disclosure, an electronic device is provided. The electronic device includes a processor and a memory coupled to the processor and storing instructions. The instructions, when executed by the processor, cause the electronic device to: obtain a file to be stored; generate an index for the hash value and the hash value of the file; record the hash value in the blockchain network; And storing the files in a distributed network where files are located based on hash values in the distributed network.

According to a third aspect of the present disclosure, an embodiment of the present disclosure further provides a computer readable storage medium. The computer readable storage medium has computer readable program instructions stored thereon. These computer-executable instructions, when executed in a device, cause the device to perform the methods or processes described in accordance with various embodiments of the present disclosure.

DRAWINGS

The features, advantages and other aspects of the various embodiments of the present disclosure will become more apparent from the aspects In the figure:

Figure 1 illustrates a schematic diagram of an architecture of a conventional blockchain network;

2 illustrates a flow diagram of a blockchain-based distributed storage method in accordance with an embodiment of the present disclosure;

3 illustrates a schematic diagram of an architecture of a blockchain-based distributed network, in accordance with one embodiment of the present disclosure;

4 illustrates a schematic diagram of an architecture of a blockchain-based distributed network, in accordance with another embodiment of the present disclosure;

FIG. 5 illustrates a schematic diagram of an architecture of a blockchain-based distributed network in accordance with yet another embodiment of the present disclosure; FIG.

6 illustrates a flow diagram of a method of obtaining a file from a blockchain-based distributed network, in accordance with an embodiment of the present disclosure;

FIG. 7 illustrates a schematic block diagram of an apparatus that can be used to implement embodiments of the present disclosure.

detailed description

Various exemplary embodiments of the present disclosure are described in detail below with reference to the drawings. The flowchart and block diagrams in the Figures illustrate the architecture, functionality and operation of possible implementations of methods and systems in accordance with various embodiments of the present disclosure. It should be noted that each block of the flowchart or block diagram may represent a module, a program segment, or a portion of code, which may include one or more for implementing various embodiments. Executable instructions for the specified logical functions. It should also be noted that in some alternative implementations, the functions noted in the blocks may also occur in a different order than that illustrated in the drawings. For example, two blocks shown in succession may in fact be executed substantially in parallel, or they can sometimes be executed in the reverse order, depending upon the functionality involved. It should also be noted that each block of the flowcharts and/or block diagrams, and combinations of blocks in the flowcharts and/or block diagrams can be implemented using a dedicated hardware-based system that performs the specified functions or operations. Or can be implemented using a combination of dedicated hardware and computer instructions.

The terms "including", "comprising", and the like, as used herein, are understood to mean an open term, that is, "including/including, but not limited to," meaning that other items may also be included. In the present disclosure, the term "based on" is "based at least in part on"; the term "one embodiment" means "at least one embodiment"; the term "another embodiment" means "at least one additional embodiment."

It is to be understood that the exemplary embodiments are given by way of example only, and are not intended to limit the scope of the invention.

Traditionally, the third-party digital signature company to ensure the authenticity of the electronic contract is less efficient, and the parties to the contract need to go to the digital signature company for forensics, and the process of obtaining evidence is cumbersome. In addition, some certification and archiving fees must be paid to the digital signature company. One improvement to the traditional contractual preservation approach is the use of blockchains to store electronic contracts. Since the electronic contract can be stored directly in the blockchain network, the method of using the blockchain facilitates rights protection, while increasing the transparency of storage and reducing costs.

However, blockchain technology uses multipoint mirroring, where data blocks are stored on each node in the blockchain network. In addition, the data of the blockchain full node is already very large, and the capacity of each node is limited, so that the summary information of the file (for example, electronic contract) can only be saved in the blockchain network, and the original file cannot be saved. Since the original file is not stored in the blockchain network, once the data is accidentally invalidated or physically deleted, the electronic contract cannot be recovered. Therefore, the blockchain technology can only be used to verify whether the electronic contract has been tampered with, but cannot guarantee the electronic contract. Availability.

Embodiments of the present disclosure provide a blockchain-based distributed storage method and apparatus. Embodiments of the present disclosure store a hash of a file in a blockchain network by combining a blockchain and a distributed file system, while dispersingly storing individual file blocks of the original file in a distributed network. Therefore, embodiments of the present disclosure can solve the problem of limited capacity of blockchain nodes, and can implement tamper-proof and distributed storage of files, thereby effectively ensuring the authenticity and usability of stored files. Exemplary methods and apparatus of embodiments of the present disclosure are described below with reference to the drawings.

FIG. 1 illustrates a schematic diagram of an architecture 100 of a conventional blockchain network. As shown in FIG. 1, architecture 100 includes

blockchain nodes

111, 112, 113, 114, 115, and 116. These blockchain nodes can synchronize data over the network, for example, the summary information of the electronic contract can be synchronized in the blockchain network. Due to the decentralization and transparency of the blockchain network, original and real electronic contract summary information can be obtained from the blockchain network as needed. However, the traditional blockchain network does not preserve the original files of the electronic contract for capacity reasons, and thus cannot guarantee the availability of the original files.

FIG. 2 illustrates a flow diagram of a blockchain based distributed storage method 200, in accordance with an embodiment of the present disclosure. It should be understood that the method 200 can be performed, for example, by the node 313 described below with respect to FIG. 3, the node 413 depicted in FIG. 4, the node 513 depicted in FIG. 5, or the device 700 of the FIG.

At 202, a file to be stored is obtained. In some embodiments, the file may be an electronic contract associated with a plurality of users, wherein each user may obtain a key (eg, a digital certificate) issued by the certificate authority through offline identity review, the key may be used for the electronic The contract is signed. For example, for an electronic contract involving two parties, one party can create an electronic contract and sign the electronic contract, and then submit the electronic contract to the blockchain network. The blockchain network then sends a request to sign the electronic contract to the other party, and when the other party completes the signature, the signature of the electronic contract and the signature status are modified in real time and stored in the blockchain network. Alternatively, the file can also be an electronic protocol, an email, a chat material, and the like.

At 204, an index is generated for the hash and hash values of the file. Those skilled in the art will appreciate that any existing or future developed hash generation method can be used to generate a hash value for a file as long as the generated hash value is capable of distinguishing between different files. In addition, an index for the hash (also known as a transaction hash) is generated and the index is provided to the user for subsequent queries.

At 206, the hash value is recorded in the blockchain network. For example, using the characteristics of decentralization and transparency of the blockchain, the generated hash value is stored in the blockchain network, which is used to identify the original file. In some embodiments, a blockchain smart contract can be used to store the hash value of a file and its corresponding signature state.

At 208, the file is stored in a distributed network where the file is located based on a hash value in the distributed network. In some embodiments, the distributed network is a point-to-point protocol based InterPlanetary File System (IPFS) network, and the IPFS distributed network maintains a distributed hash table. IPFS uses a content-based address instead of the traditional domain-based approach. When a new file is added to an IPFS distributed network, the hash of the file is used as an index into the IPFS distributed network. If there are any modifications to the file, its corresponding hash value will change. The file is safer and more reliable because it uses the hash of the file to find the file.

Compared with the blockchain network, each node in the IPFS distributed network only stores a part of data. In the IPFS distributed network, the files are divided into multiple file blocks and distributed in each node for storage and backup, making the file more difficult to be attacked. Or have been tampered with. It should be understood that while embodiments of the present disclosure have primarily described embodiments of the present disclosure with an IPFS distributed network as an example, other distributed networks that locate files based on hash values are also feasible.

In some embodiments, the file can be completed in multiple nodes stored in the IPFS. Alternatively, the file may also be sliced into a plurality of file blocks, and then the plurality of file blocks may be distributedly stored in a plurality of nodes in the IPFS distributed network. To ensure data backup and redundancy, each file block is stored in at least two of the plurality of nodes.

Therefore, according to the method 200 of the embodiment of the present disclosure, the hash value of the file to be preserved is stored in the blockchain network, and the original file is stored in the distributed network, thereby ensuring the authenticity of the file. It also guarantees the availability of files, and makes up for the shortcomings of blockchain nodes with limited capacity and linear expansion of storage space. In addition, when it is necessary to check documents (such as electronic contracts), the parties to the electronic contract can obtain electronic contracts from the distributed network based on the blockchain after being authenticated.

FIG. 3 illustrates a schematic diagram of an architecture 300 of a blockchain-based distributed network, in accordance with one embodiment of the present disclosure. As shown in FIG. 3, architecture 300 includes a blockchain network 310 and an IPFS distributed network 320, wherein blockchain network 310 includes

blockchain nodes

311, 312, 313, 314, 315, and 316, while IPFS distributed network 320 Distributed

nodes

321, 322, 323, 324, and 325 are included. Moreover, as shown in FIG. 3, architecture 300 can also include

computing devices

330 and 340. In some embodiments, the supervisory authority can dock the blockchain network to become a node in the blockchain network. For example, the device of the supervisory department can be the blockchain node 311, and then all the data in the blockchain network can be obtained. To perform regulatory duties. The blockchain network supports node automatic data synchronization, that is, any node in the blockchain network can obtain a complete data backup on the blockchain.

Each of the blockchain nodes 311-316 and the distributed nodes 321-325 can be a computing device, which can be a server or user device (eg, a mobile device such as a smartphone, tablet, laptop, etc., or fixed) Devices, such as desktop computers). Those skilled in the art will appreciate that although some of the nodes in the blockchain network 310 and the IPFS distributed network 320 are shown in FIG. 3, other nodes may be included.

In some embodiments, the block chain nodes 311-316 in the blockchain network 310 synchronize data blocks through the network, while the nodes 321-325 in the IPFS distributed network 320 implement distributed file storage over the network, blocks. The chain network 310 and the IPFS distributed network 320 are also connected through a network. The network can be any wired and/or wireless network. Alternatively, the network may include, but is not limited to, the Internet, a wide area network, a metropolitan area network, a local area network, a virtual private network (VPN) network, a wireless communication network, and the like.

In one embodiment, computing device 330 submits the electronic contract to blockchain node 313, which then generates a hash value for the electronic contract and its index from blockchain node 313, storing the hash value in distributed network 310. And providing an index to computing device 330. Computing device 340 can then sign the electronic contract and store the signed signature status in blockchain network 310. Next, blockchain node 313 can send the file to IPFS distributed network 320 for distributed storage. For example, a file can be divided into multiple file blocks and stored in a distributed manner in the IPFS distributed network 320, where files can be looked up by hash values. Since the hash value of the file is stored in the blockchain network 310, it can be verified that the file has not been tampered with, and further, since the file is distributedly stored in the IPFS distributed network 320, since the file is usually not lost, The availability of the file can be guaranteed.

4 illustrates a schematic diagram of an architecture 400 of a blockchain-based distributed network, in accordance with another embodiment of the present disclosure. As shown in FIG. 4, architecture 400 includes a blockchain network 410 and an IPFS distributed network 420, wherein blockchain network 410 includes

blockchain nodes

411, 412, 413, 414, 415, and 416, while IPFS distributed network 420 Distributed

nodes

421, 422, 423, 424, 425, 413, and 414 are included.

The difference from the architecture 300 depicted in FIG. 3 is that the blockchain network 310 and the IPFS distributed network 320 in FIG. 3 are completely separate, with no duplication between nodes; and the blockchain network 410 in FIG. There is a partial overlap with the IPFS distributed network 420, that is, some nodes act as both blockchain nodes and distributed nodes, such as

nodes

413, 414. For example, blockchain programs and distributed storage programs are run concurrently on

nodes

413 and 414 such that

nodes

413 and 414 store both the hash value of the file and the file block of the file.

FIG. 5 illustrates a schematic diagram of an architecture 500 of a blockchain-based distributed network, in accordance with yet another embodiment of the present disclosure. As shown in FIG. 5, the architecture 500 includes a network 510, and the network 510 acts both as a blockchain network and as an IPFS distributed network, that is, the blockchain network and the IPFS distributed network completely overlap, wherein the network 510 includes

nodes

511, 512, 513, 514, 515, 516. As shown in FIG. 5, each of the nodes 511-516 is both a blockchain node and a distributed node, and each node simultaneously runs a blockchain program and a distributed storage program, so that all nodes store files. Greek value, and each node only stores a portion of the file block in the file.

According to the architectures 300-500 of the embodiments of the present disclosure, tamper resistance, loss prevention, and secure backup storage of files can be achieved. In addition, any participant or supervisory authority may join the blockchain network as a member node for notarization and supervision.

FIG. 6 illustrates a flow diagram of a method 600 of obtaining a file from a blockchain-based distributed network, in accordance with an embodiment of the present disclosure. It should be understood that the method 200 can be performed, for example, by the node 313 described above with respect to FIG. 3, the node 413 depicted in FIG. 4, the node 513 depicted in FIG. 5, and the apparatus 700 described below with reference to FIG.

At 602, a hash value is obtained from the blockchain network based on the index, for example, the blockchain node 313 looks up the hash value in the blockchain network 310 based on the index received from the computing device 330, and then uses the hash value The distributed hash table in the IPFS distributed network 320 is queried. At 604, it is determined whether the hash value exists in the distributed hash table, for example, using the hash value to query all records in the distributed hash table, and when identical, the hash value exists in the distributed hash table. . If so, the file is obtained from the IPFS distributed network 320 by the hash value at 606. This file is true and reliable because it is a file obtained from unmodified hash values in the blockchain network. At 608, the signature status of the file can be verified from the blockchain network, for example, verifying that the electronic contract has been signed by computing

devices

330 and 340. If the hash value does not exist in the distributed hash table, then at 610 the file is indicated to be modified in the distributed network. Because IPFS distributed networks have backup and redundancy mechanisms, files in IPFS distributed networks are usually not corrupted or modified. According to an embodiment of the present disclosure, since the hash value of the file is not modified in the blockchain network, the file obtained from the IPFS distributed network is also the original file that has not been tampered with.

Therefore, the embodiment of the present disclosure can solve the problem of limited capacity of the blockchain node by combining the blockchain and the distributed file system, and can implement tamper-proof and distributed storage of the file, thereby effectively ensuring the stored The authenticity and usability of the document. In addition, compared with the traditional third-party signature authentication method, the embodiment of the present disclosure has a simple forensic process and a short cycle, and effectively improves the forensic efficiency of the electronic contract.

In some embodiments, new user equipment can be used to access the blockchain network and the IPFS distributed network. For example, the metadata of the file (eg, a hash value) is obtained from the blockchain network based on the index, and then the original file is obtained from the IPFS distributed network based on the hash value. Alternatively or additionally, the user equipment constructs local data blocks locally each time it is queried, making it part of the blockchain network node, thereby better ensuring decentralized storage of data.

It should be understood that devices in accordance with embodiments of the present disclosure may be implemented in a variety of manners. For example, in some embodiments, the device can be implemented in hardware, software, or a combination of software and hardware. The hardware portion can be implemented using dedicated logic; the software portion can be stored in memory and executed by a suitable instruction execution system, such as a microprocessor or dedicated design hardware. One of ordinary skill in the art will appreciate that the methods and systems described above can be implemented using computer-executable instructions and/or embodied in processor control code, such as in a programmable memory such as a magnetic disk, an optical disk carrier medium, or a read only memory. Such code is provided on a data carrier such as an optical or electronic signal carrier. The apparatus and apparatus of embodiments of the present disclosure may be implemented not only by hardware such as very large scale integrated circuits or gate arrays, semiconductors such as logic chips, transistors, etc., or programmable hardware devices such as field programmable gate arrays, programmable logic devices, and the like. The circuit implementation can also be implemented by, for example, software executed by various types of processors, or by a combination of the above hardware circuits and software.

FIG. 7 illustrates a schematic block diagram of an electronic device 700 that can be used to implement embodiments of the present disclosure. It should be understood that electronic device 700 can be implemented as any of the nodes described in Figures 3-5, or electronic device 700 can be implemented as any of any of the nodes described in Figures 3-5. As shown in FIG. 7, device 700 includes a central processing unit (CPU) 701 (eg, a processor) that can be loaded into random access memory from computer program instructions stored in read only memory (ROM) 702 or from storage unit 708 ( Computer program instructions in RAM) 703 to perform various appropriate actions and processes. In the RAM 703, various programs and data required for the operation of the device 700 can also be stored. The CPU 701, the ROM 702, and the RAM 703 are connected to each other through a bus 704. An input/output (I/O) interface 705 is also coupled to bus 704.

A plurality of components in device 700 are coupled to I/O interface 705, including: input unit 706, such as a keyboard, mouse, etc.; output unit 707, such as various types of displays, speakers, etc.; storage unit 708, such as a magnetic disk, optical disk, etc. And a communication unit 709 such as a network card, a modem, a wireless communication transceiver, and the like. Communication unit 709 allows device 700 to exchange information/data with other devices over a computer network such as the Internet and/or various telecommunication networks.

The various methods described above, such as

method

200 or 600, may be performed by processing unit 701. For example, in some embodiments,

methods

200 and 600 can be implemented as a computer software program that is tangibly embodied in a machine readable medium, such as storage unit 708. In some embodiments, some or all of the computer program may be loaded and/or installed onto device 700 via ROM 702 and/or communication unit 709. When a computer program is loaded into RAM 703 and executed by CPU 701, one or more of the acts or steps of

methods

200 and 600 described above may be performed.

The computer program product can include a computer readable storage medium having computer readable program instructions for performing various aspects of the present disclosure. The computer readable storage medium can be a tangible device that can hold and store the instructions used by the instruction execution device. The computer readable storage medium can be, for example, but not limited to, an electrical storage device, a magnetic storage device, an optical storage device, an electromagnetic storage device, a semiconductor storage device, or any suitable combination of the foregoing. More specific examples (non-exhaustive list) of computer readable storage media include: portable computer disks, hard disks, random access memory (RAM), read only memory (ROM), erasable programmable read only memory (EPROM) Or flash memory), static random access memory (SRAM), portable compact disk read only memory (CD-ROM), digital versatile disk (DVD), memory stick, floppy disk, mechanical encoding device, for example, with instructions stored thereon A raised structure in the hole card or groove, and any suitable combination of the above. A computer readable storage medium as used herein is not to be interpreted as a transient signal itself, such as a radio wave or other freely propagating electromagnetic wave, an electromagnetic wave propagating through a waveguide or other transmission medium (eg, a light pulse through a fiber optic cable), or through a wire The electrical signal transmitted.

The computer readable program instructions described herein can be downloaded to a respective computing/processing device from a computer readable storage medium or downloaded to an external computer or external storage device over a network, such as the Internet, a local area network, a wide area network, and/or a wireless network. The network may include copper transmission cables, fiber optic transmissions, wireless transmissions, routers, firewalls, switches, gateway computers, and/or edge servers. A network adapter card or network interface in each computing/processing device receives computer readable program instructions from the network and forwards the computer readable program instructions for storage in a computer readable storage medium in each computing/processing device .

Computer program instructions for performing the operations of the present disclosure may be assembly instructions, instruction set architecture (ISA) instructions, machine instructions, machine related instructions, microcode, firmware instructions, state setting data, or in one or more programming languages. Source code or object code written in any combination, including an object oriented programming language - such as C++, and conventional procedural programming languages - such as the "C" language or similar programming language. The computer readable program instructions can execute entirely on the user's computer, partly on the user's computer, as a stand-alone software package, partly on the user's computer, partly on the remote computer, or entirely on the remote computer or server. carried out. In the case of a remote computer, the remote computer can be connected to the user's computer via any kind of network, including a local area network (LAN) or wide area network (WAN), or can be connected to an external computer (eg, using an Internet service provider to access the Internet) connection). In some embodiments, the customized electronic circuit, such as a programmable logic circuit, a field programmable gate array (FPGA), or a programmable logic array (PLA), can be customized by utilizing state information of computer readable program instructions. Computer readable program instructions are executed to implement various aspects of the present disclosure.

It should be noted that although several modules or sub-modules of the device are mentioned in the above detailed description, such division is merely exemplary and not mandatory. Indeed, in accordance with embodiments of the present disclosure, the features and functions of the two or more modules described above may be embodied in one module. Conversely, the features and functions of one of the modules described above may be further divided into multiple modules.

The above is only an alternative embodiment of the embodiments of the present disclosure, and is not intended to limit the embodiments of the present disclosure, and various modifications and changes can be made to the embodiments of the present disclosure. Any modifications, equivalent substitutions, improvements, etc. within the spirit and scope of the embodiments of the present disclosure are intended to be included within the scope of the embodiments of the present disclosure.

Although the embodiments of the present disclosure have been described with reference to the specific embodiments thereof, it is understood that the embodiments of the present disclosure are not limited to the specific embodiments disclosed. The various embodiments of the present disclosure are intended to cover various modifications and equivalents. The scope of the following claims is to be accorded

Claims

A distributed storage method based on blockchain, comprising:

Obtain the file to be stored;

Generating an index for the hash value of the file and the hash value;

Recording the hash value in a blockchain network;

The file is stored in a distributed network, the file being located in the distributed network based on the hash value.
The method of claim 1 wherein said distributed network is a Point-to-Point Protocol based Interstellar File System (IPFS) network and said distributed network maintains a distributed hash table.
The method of claim 2 wherein storing the file in a distributed network comprises:

Dividing the file into multiple file blocks;

A plurality of file blocks are stored in a plurality of nodes in the distributed network, wherein each of the plurality of file blocks is stored in at least two of the plurality of nodes.
The method of claim 2 further comprising:

Obtaining the hash value from the blockchain network based on the index;

The file is obtained from the distributed network based on the hash value.
The method of claim 4 wherein obtaining the file from the distributed network based on the hash value comprises:

Determining whether the hash value is present in the distributed hash table;

The file is obtained from the distributed network in response to determining that the hash value is present in the distributed hash table.
A method according to claim 1 or 2, wherein said file is an electronic contract associated with a plurality of users, and each of said plurality of users is capable of performing said electronic contract using a respective signature key The signature, as well as the files in which it is to be stored, include:

Obtaining the electronic contract from one of the plurality of users, the electronic contract being generated using a signature key of the one user;

A request to sign the electronic contract is sent to other ones of the plurality of users.
The method of claim 6 further comprising:

Receiving a signature for the electronic contract from other ones of the plurality of users;

Modifying the contract signature status of the electronic contract;

The modified contract signature status is stored in the blockchain network.
The method of claim 1 or 2, wherein the file is at least one of an electronic contract, an electronic agreement, an email, or a chat material.
An electronic device, including

processor;

A memory coupled to the processor and storing instructions that, when executed by the processor, cause the device to perform the following actions:

Obtain the file to be stored;

Generating an index for the hash value of the file and the hash value;

Recording the hash value in a blockchain network;

The file is stored in a distributed network, the file being located in the distributed network based on the hash value.
The apparatus of claim 9, wherein the distributed network is a Point-to-Point Protocol-based Interstellar File System (IPFS) network, and the distributed network maintains a distributed hash table.
The device of claim 10 wherein storing the file in a distributed network comprises:

Dividing the file into multiple file blocks;

A plurality of file blocks are stored in a plurality of nodes in the distributed network, wherein each of the plurality of file blocks is stored in at least two of the plurality of nodes.
The device of claim 10, the action further comprising:

Obtaining the hash value from the blockchain network based on the index;

The file is obtained from the distributed network based on the hash value.
The device of claim 12, wherein obtaining the file from the distributed network based on the hash value comprises:

Determining whether the hash value is present in the distributed hash table;

The file is obtained from the distributed network in response to determining that the hash value is present in the distributed hash table.
The apparatus according to claim 9 or 10, wherein said file is an electronic contract associated with a plurality of users, and each of said plurality of users is capable of performing said electronic contract using a respective signature key The signature, as well as the files in which it is to be stored, include:

Obtaining the electronic contract from one of the plurality of users, the electronic contract being generated using a signature key of the one user;

A request to sign the electronic contract is sent to other ones of the plurality of users.
The device of claim 14, the action further comprising:

Receiving a signature for the electronic contract from other ones of the plurality of users;

Modifying the contract signature status of the electronic contract;

The modified contract signature status is stored in the blockchain network.
The device according to claim 9 or 10, wherein the file is at least one of an electronic contract, an electronic agreement, an email, or a chat material.
A computer readable storage medium comprising computer executable instructions that, when executed in a device, cause the device to perform the method of any of claims 1-8.