CN111026583B - Backup and recovery methods and computer-readable storage media for multiple private keys in blockchain wallets - Google Patents

Abstract

The application relates to a backup and recovery method of multi-private key of a block chain wallet, wherein the backup method comprises the following steps: generating a character string of the multi-private key of the blockchain wallet; encrypting the character string through the biological characteristic value to obtain private key backup information; and generating the ciphertext picture by using the private key backup information by adopting an image steganography technology. The application also discloses a method for recovering the multi-private key of the blockchain wallet and two computer readable storage media. The application can enhance the safety without purchasing additional equipment.

Description

Backup and recovery methods and computer-readable storage media for multiple private keys in blockchain wallets

Technical field

The present invention relates to the field of blockchain technology, and in particular to a method for backing up and restoring multiple private keys of a blockchain wallet.

Background technique

With the rapid development of blockchain technology, blockchain wallet, as a private key management tool, can save multiple private keys. However, these private keys are at risk of being lost when device power outages, natural disasters, hacker attacks, etc. occur.

Regarding the backup of blockchain wallet private keys, one of the common ways is to back up on the client. In the existing invention patent "CN201811542521 Blockchain account key backup and recovery method, device, terminal and system", the inventor proposes a solution for backing up the user's blockchain wallet key in an external device, a key backup device It can be various external storage devices such as U disk, mobile hard disk, read-only memory, optical disk, etc.

Another way to back up blockchain wallet private keys is server-side backup. "CN201710630879.1 A method, device and system for protecting blockchain private keys" hides the user's private key in the field in the header of the original transaction block, obtains the transaction block with hidden information, and converts the transaction with hidden information The block is linked on the blockchain, obtains the user's extraction instructions, and extracts the private key from the transaction block on the blockchain according to the extraction instructions.

However, the inventor of the present invention found that the above-mentioned first solution requires the user to purchase additional equipment as a backup and storage carrier for the key, which increases the implementation cost of the solution; the second solution saves the backup private key file in the cloud, making it difficult for hackers to After breaking into the cloud or being able to crack the private key file, you can obtain all the private key files stored in the cloud, which has a high hidden risk.

Contents of the invention

The technical problem to be solved by the present invention is to provide a method for backing up and restoring multiple private keys of a blockchain wallet, which can enhance security without purchasing additional equipment.

The technical solution adopted by the present invention to solve the technical problem is to provide a method for backing up multiple private keys of a blockchain wallet, which includes the following steps:

(A) Generate a string of multiple private keys for the blockchain wallet;

(B) Encrypt the string using biometric values to obtain private key backup information;

(C) Use image steganography technology to generate ciphertext images from private key backup information.

When the step (A) generates the ciphertext of multiple private keys in the blockchain wallet, all the private keys in the user's blockchain wallet are spliced together and a string is generated; the string includes the private key indicator bit length definition code , private key indication bit and private key splicing bit; the length definition code of the private key indication bit is located in the first 10 digits of the generated string and is generated according to the length of the private key indication bit; the private key indication bit is composed of each The end position of the private key is composed of the end position of its description information; the private key splicing bit is the backup private key and its description information, which are spliced in the order of export.

The step (B) is specifically: obtain the user's biometric information and save it; extract the biometric data and generate a key K based on the biometric data; use the key K to generate the multi-private key of the blockchain wallet in plain text format. Encrypt the string to obtain the private key backup information.

The specific steps (C) are: convert the private key backup information into binary numbers; randomly obtain a picture for steganographic information; read the information of each layer of the RGB layer of the picture, and then convert the private key backup information to The binary digits replace the last digit of each layer of information in the RGB layer of the image in turn to obtain the ciphertext image and save it.

The technical solution adopted by the present invention to solve the technical problem is to provide a method for recovering multiple private keys of a blockchain wallet, which includes the following steps:

(a) According to the user's request, use image steganography technology to restore the private key backup information of the blockchain wallet;

(b) Use biometric values to decrypt the private key backup information;

(c) Restore the multi-private key information of the blockchain wallet.

The specific step (a) is: reading the information of each layer of the RGB layer of the picture in binary form, and arranging it in the original order of the ciphertext pictures to obtain the private key backup information of the blockchain wallet.

The specific step (b) is: comparing the user's biometric information with the pre-stored biometric information, if they match, retrieve the corresponding key K, and use the key K to decrypt the private key backup information.

The specific step (c) is: locating the position of the private key indication bit according to the length definition code of the private key indication bit, and then determining the position of each private key and its description information according to the private key indication bit and extracting the corresponding string, Finally, the recovery information of the blockchain wallet private key is generated.

The technical solution adopted by the present invention to solve the technical problem is to provide a computer-readable storage medium that stores a backup program for the multiple private keys of the blockchain wallet, and the multiple private keys of the blockchain wallet are stored in the computer-readable storage medium. When the key backup program is executed by the processor, the above-mentioned backup method of multiple private keys of the blockchain wallet is implemented.

The technical solution adopted by the present invention to solve the technical problem is to provide a computer-readable storage medium, which stores a recovery program for multiple private keys of a blockchain wallet, and the multiple private keys of the blockchain wallet are stored in the computer-readable storage medium. When the key recovery program is executed by the processor, the above-mentioned blockchain wallet multi-private key recovery method is implemented.

beneficial effects

Due to the adoption of the above technical solution, the present invention has the following advantages and positive effects compared with the existing technology: the present invention encrypts the user's multiple private keys biometrically and provides them to the user in the form of pictures for local backup; This method can back up multiple private keys of the user's wallet at one time, and perform encryption and decryption of ciphertext based on the user's biometric characteristics, which enhances the security of backup and recovery. After the private key is encrypted, the ciphertext is saved by the user himself. Compared with saving in Cloud solutions are more private.

Description of the drawings

Figure 1 is a flow chart of the backup and recovery of multiple private keys of the blockchain wallet in the present invention;

Figure 2 is a schematic diagram of private key splicing rules in the first embodiment of the present invention;

Figure 3 is a flow chart of using biometric information for encryption in the first embodiment of the present invention;

Figure 4 is a diagram of the least significant bit replacement process in the first embodiment of the present invention;

Figure 5 is a flow chart of using biometric information for decryption in the second embodiment of the present invention;

Figure 6 is a flow chart of private key information recovery in the second embodiment of the present invention.

Detailed ways

The present invention will be further described below in conjunction with specific embodiments. It should be understood that these examples are only used to illustrate the invention and are not intended to limit the scope of the invention. In addition, it should be understood that after reading the teachings of the present invention, those skilled in the art can make various changes or modifications to the present invention, and these equivalent forms also fall within the scope defined by the appended claims of this application.

The first embodiment of the present invention relates to a method for backing up multiple private keys in a blockchain wallet, as shown in Figure 1, which includes the following steps:

Step 1: Generate wallet multi-private keys.

After a user initiates a private key backup request, the wallet to be backed up may contain multiple private keys belonging to different blockchains, and the lengths of the private keys may be different. Therefore, during backup, the server will splice all the private keys in the user's wallet. And generate a string, as shown in Figure 2. The string includes three parts: the private key indication bit length definition code, the private key indication bit and the private key splicing bit. The specific splicing rules are as follows:

1. Private key indicator bit length definition code: Since this implementation can back up multiple blockchain wallet private keys, the length of the spliced string is uncertain. In order to be able to identify the "" in the string during the private key recovery process The specific position of the "Private Key Indicator Bit". The first 10 digits of the string generate a "Private Key Indicator Bit Length Definition Code" based on the length of the "Private Key Indicator Bit". Its storage format is decimal. The remaining digits are * is filled in.

2. Private key indicator bit: In order to locate the location and description information of each private key stored in the string, the second part of the string is the "private key indicator bit", which consists of the end position of each private key and the description information. It consists of the end position, in which the starting position of the first private key can be calculated based on the length definition code of the private key indication bit. All private key indication bits are expressed in hexadecimal form and separated by "#". The indication bits of each two private keys are separated by "/";

3. Private key splicing bit: In the third part of the string, string splice the backed up private key and its description information in the order of export.

Step 2: Encrypt the ciphertext through biometric values.

Since the generated private key string is stored in clear text, in order to ensure the security of the backup file, this implementation uses biometric values to encrypt the private key string. The user's encryption and decryption of the private key backup file are based on fingerprint authentication. The encryption process is shown in Figure 3, and the details are as follows:

1. After the user initiates a private key backup request, the user enters his biometric information through the fingerprint authentication device, uploads it and saves it on the server;

2. Extract fingerprint feature data such as breakpoints and bifurcation points of the fingerprint ridge, and generate the AES256 key K through the hash value (256 bits) after SHA256;

3. Use key K to encrypt the private key string A in plain text format;

4. After the encryption is completed, ciphertext C is generated, which is the private key backup information.

Step 3: Generate ciphertext image.

In order to enhance the confidentiality of the private key backup file, this implementation uses LSB least significant bit image steganography technology to steganography the backup information of the private key into the image file. The specific steps are as follows:

1. Binary conversion private key backup information

Since RGB images are generally composed of the three primary colors of RGB (red, green and blue), each color occupies 8 bits and is composed of binary numbers. This implementation method converts the private key backup information into binary numbers.

2. Capture images used for steganography

After the server completes AES encryption of the private key backup information, it will randomly grab a picture for steganographic information from the Internet. This implementation method will first read the length of the binary-converted private key backup information to ensure that the captured image is enough to accommodate the ciphertext writing requirement.

3. Least significant bit replacement

Read the information of each layer of RGB layer of the picture captured on the Internet, and then replace the last bit (LSB) of each layer of information of the RGB layer of the picture with the binary number of the private key backup information. The process is shown in Figure 4. . After the replacement is completed, the server generates a picture that is almost indistinguishable to the naked eye, in which the backup information of the private key is hidden, and the user is reminded to save it to a designated place.

The second embodiment of the present invention relates to a method for recovering multiple private keys of a blockchain wallet. As shown in Figure 1, it includes the following steps:

Step 4: Initiate a wallet private key recovery request.

The user initiates a key recovery request on the local wallet client, uploads the ciphertext image to the server, and collects the user's fingerprint information through a fingerprint collector.

Step 5: Restore the wallet private key backup information.

The server reads each layer of information in the RGB layer of the picture in binary form and arranges it in the original order of the picture; since the backup information of the private key is hidden in the LSB layer of the picture, R and G are extracted , the last bit (LSB) of each layer of B, and splice the information in order to obtain the backup information of the private key.

Step 6: Decrypt the ciphertext using biometric values.

The biometric decryption process is shown in Figure 5, and the details are as follows:

1. Compare the fingerprint information collected this time with the fingerprint information pre-stored on the server side. If they match, retrieve the corresponding key K on the server side;

2. Use key K to decrypt the private key backup information;

3. Obtain the plaintext of the private key.

Step 7: Recover wallet private key information.

The decrypted private key backup information contains multiple private keys of the user's blockchain wallet account. Therefore, in order to ultimately restore the backup file to each independent private key, the string file needs to be interpreted.

As shown in Figure 6, when the server interprets the private key backup string file, it first locates the position of the private key indication bit according to the length definition code of the private key indication bit. Then the location of each private key and its description information is determined according to the private key indication bit and the corresponding string is extracted, and finally the recovery information of the wallet private key is generated.

It is not difficult to find that the present invention encrypts the user's multiple private keys with biometric features and provides them to the user for local backup in the form of pictures. This method can back up multiple private keys of the user's wallet at one time, and performs encryption based on the user's biometric features. Encryption and decryption of ciphertext enhances the security of backup and recovery. After encrypting the private key, the ciphertext is saved by the user himself, which is more confidential than the solution stored in the cloud.

The third embodiment of the present invention relates to a computer-readable storage medium that stores a backup program for multiple private keys of a blockchain wallet, and the backup program for multiple private keys of a blockchain wallet is processed When the server is executed, the backup method of multiple private keys of the blockchain wallet of the first embodiment is implemented.

The fourth embodiment of the present invention also relates to a computer-readable storage medium that stores a recovery program for multiple private keys of a blockchain wallet. The recovery program for multiple private keys of a blockchain wallet is When the processor executes, the method for recovering multiple private keys of the blockchain wallet of the second embodiment is implemented.

Claims (4)

1. A method for backing up multiple private keys in a blockchain wallet, which is characterized by including the following steps: (A) Generate a string of multiple private keys in the blockchain wallet; when generating the ciphertext of the multiple private keys in the blockchain wallet, splice all the private keys in the user's blockchain wallet and generate a string; the characters The string includes a private key indicator bit length definition code, a private key indicator bit and a private key splicing bit; the private key indicator bit length definition code is located 10 digits before the beginning of the generated string and is generated based on the length of the private key indicator bit. ; The private key indication bit is composed of the end position of each private key and the end position of its description information; the private key splicing bit is the backup private key and its description information that are spliced in the order of export; (B) Encrypt the string through the biometric value to obtain the private key backup information; specifically: obtain the user's biometric information and save it; extract the biometric data, and generate the key K based on the biometric data; Use key K to encrypt the string of multiple private keys of the blockchain wallet in plain text format to obtain the private key backup information; (C) Use image steganography technology to generate a ciphertext image from the private key backup information; specifically: convert the private key backup information into binary numbers; randomly obtain a picture for steganographic information; read the RGB layer of the picture For each layer of information, the last digit of each layer of information in the RGB layer of the image is replaced with the binary number of the private key backup information in order to obtain the ciphertext image and save it. 2. A method for recovering multiple private keys in a blockchain wallet, which is characterized by including the following steps: (a) According to the user's request, use image steganography technology to restore the private key backup information of the blockchain wallet; specifically: read each layer of information in the RGB layer of the image in binary form, and follow the original order of the ciphertext image. Arrange to obtain the private key backup information of the blockchain wallet; (b) Use the biometric value to decrypt the private key backup information; specifically: compare the user's biometric information with the pre-stored biometric information, and if they match, retrieve the corresponding key K and use the key K Decrypt the private key backup information; (c) Restore the multi-private key information of the blockchain wallet; specifically: locate the position of the private key indication bit according to the length definition code of the private key indication bit, and then determine the location of each private key and its description information based on the private key indication bit. And extract the corresponding string, and finally generate the recovery information of the blockchain wallet private key. 3. A computer-readable storage medium, characterized in that the computer-readable storage medium stores a backup program for multiple private keys of a blockchain wallet, and the backup program for multiple private keys of a blockchain wallet is executed by a processor. When realizing the backup method of multiple private keys of a blockchain wallet as claimed in claim 1. 4. A computer-readable storage medium, characterized in that the computer-readable storage medium stores a recovery program for multiple private keys of a blockchain wallet, and the recovery program for multiple private keys of a blockchain wallet is executed by a processor. When realizing the method for recovering multiple private keys of a blockchain wallet as claimed in claim 2.