A reversible information hiding method and system based on shared domain encryption

Abstract

The present application discloses a shared domain reversible information hiding method and system based on re-encryption, which relates to the field of information hiding technology. The method includes encrypting a plaintext carrier according to an encryption key and a secret sharing encryption algorithm to obtain a number of preliminary ciphertext carriers; encrypting the several preliminary ciphertext carriers according to the encryption key and the secret sharing encryption algorithm to obtain a number of final ciphertext carriers; wherein the determination process of each of the final ciphertext carriers is as follows: selecting a second preset number of preliminary ciphertext carriers, encrypting the second preset number of preliminary ciphertext carriers according to the encryption key and the secret sharing encryption algorithm to obtain a final ciphertext carrier; finally, sending the several final ciphertext carriers to several information hiding parties. The present application can reduce the difficulty of embedding ciphertext carrier data and realize the dynamic adjustment of ciphertext carrier generation.

Description

Technical Field

[0001] The present application relates to the field of information hiding technology, and in particular to a method and system for reversible information hiding in a shared domain based on re-encryption. Background Art

[0002] Reversible information hiding in the ciphertext domain first encrypts the plaintext carrier into a ciphertext carrier and sends it to a single information hiding party for data embedding. The data is then embedded into the ciphertext carrier to generate a secret ciphertext carrier. Finally, the embedded data is extracted from the secret ciphertext carrier and the original plaintext carrier is recovered. Reversible information hiding in the ciphertext domain is primarily used for carrier tamper detection and integrity verification.

[0003] In order to improve the recoverability of plaintext carriers, shared domain reversible information hiding technology has been proposed. It first encrypts the plaintext carrier into multiple ciphertext carriers and sends them to multiple different information hiding parties for data embedding. Then, the multiple data are independently embedded into the multiple ciphertext carriers to generate corresponding encrypted ciphertext carriers. Finally, the receiver selects any sufficient number of encrypted ciphertext carriers from the information hiding party to extract the embedded data and restore the original plaintext carrier. Shared domain reversible information hiding technology can ensure that even if some information hiding parties are attacked and cannot provide encrypted ciphertext carriers, the receiver can still obtain the encrypted ciphertext carriers from the information hiding parties that have not been attacked to achieve data extraction and plaintext carrier recovery. However, shared domain reversible information hiding technology still has the following disadvantages: the ciphertext carriers are difficult to use directly for data embedding, and the generation of ciphertext carriers cannot be dynamically adjusted. Summary of the Invention

[0004] The purpose of this application is to provide a shared domain reversible information hiding method and system based on re-encryption, which can reduce the difficulty of embedding ciphertext carrier data and realize dynamic adjustment of ciphertext carrier generation.

[0005] To achieve the above objectives, this application provides the following solutions:

[0006] In a first aspect, the present application provides a shared domain reversible information hiding method based on re-encryption, comprising:

[0007] Get the plaintext carrier.

[0008] The plaintext carrier is encrypted according to the encryption key and the secret sharing encryption algorithm to obtain a plurality of preliminary ciphertext carriers; wherein a first preset number of the preliminary ciphertext carriers are used to restore the plaintext carrier; the number of the first preset number of the preliminary ciphertext carriers is greater than or equal to 2 and less than or equal to the number of the preliminary ciphertext carriers.

[0009] According to the encryption key and the secret sharing encryption algorithm, several copies of the preliminary ciphertext carriers are encrypted to obtain several copies of the final ciphertext carriers; wherein the number of copies of the final ciphertext carriers is the same as the number of copies of the preliminary ciphertext carriers; the determination process of each copy of the final ciphertext carrier is: selecting the preliminary ciphertext carriers of a second preset number, and encrypting the preliminary ciphertext carriers of the second preset number according to the encryption key and the secret sharing encryption algorithm to obtain the final ciphertext carrier; the number of the second preset number of copies is less than the number of the first preset number of copies.

[0010] Several copies of the final ciphertext carrier are sent to several information hiding parties; the number of the information hiding parties is the same as the number of copies of the final ciphertext carrier; each of the information hiding parties is used to embed data into a copy of the final ciphertext carrier to obtain a secret ciphertext carrier, and send the secret ciphertext carrier to a receiving party; the receiving party is used to extract data and recover the carrier based on a third preset number of secret ciphertext carriers to obtain the embedded data and the plaintext carrier; the number of the third preset number of copies is equal to the number of the first preset number of copies minus the number of the second preset number of copies plus 1.

[0011] In a second aspect, the present application provides another shared domain reversible information hiding method based on re-encryption, including:

[0012] The encryption party obtains the plaintext carrier.

[0013] The encryption party encrypts the plaintext carrier according to the encryption key and the secret sharing encryption algorithm to obtain a plurality of preliminary ciphertext carriers; wherein, a first preset number of the preliminary ciphertext carriers are used to restore the plaintext carrier; the number of the first preset number of copies is greater than or equal to 2 and less than or equal to the number of the preliminary ciphertext carriers.

[0014] The encryption party encrypts several copies of the preliminary ciphertext carriers according to the encryption key and the secret sharing encryption algorithm to obtain several copies of the final ciphertext carriers; wherein the number of copies of the final ciphertext carriers is the same as the number of copies of the preliminary ciphertext carriers; the determination process of each copy of the final ciphertext carrier is: selecting the preliminary ciphertext carriers of a second preset number, and encrypting the preliminary ciphertext carriers of the second preset number according to the encryption key and the secret sharing encryption algorithm to obtain the final ciphertext carrier; the number of the second preset number of copies is less than the number of the first preset number of copies.

[0015] The encryption party sends several copies of the final ciphertext carrier to several information hiding parties; the number of the information hiding parties is the same as the number of copies of the final ciphertext carrier.

[0016] Each of the information hiding parties embeds data into a copy of the final ciphertext carrier to obtain a secret-containing ciphertext carrier, and sends the secret-containing ciphertext carrier to a receiving party.

[0017] The receiver extracts data and recovers the encrypted carrier based on the third preset number of encrypted ciphertext carriers to obtain the embedded data and the plaintext carrier; the number of the third preset number of copies is equal to the number of the first preset number of copies minus the number of the second preset number of copies plus 1.

[0018] In a third aspect, the present application provides a shared domain reversible information hiding system based on re-encryption, comprising:

[0019] Encryption parties are used to:

[0020] Get the plaintext carrier.

[0021] The plaintext carrier is encrypted according to the encryption key and the secret sharing encryption algorithm to obtain a plurality of preliminary ciphertext carriers; wherein a first preset number of the preliminary ciphertext carriers are used to restore the plaintext carrier; the number of the first preset number of the preliminary ciphertext carriers is greater than or equal to 2 and less than or equal to the number of the preliminary ciphertext carriers.

[0022] According to the encryption key and the secret sharing encryption algorithm, several copies of the preliminary ciphertext carriers are encrypted to obtain several copies of the final ciphertext carriers; wherein the number of copies of the final ciphertext carriers is the same as the number of copies of the preliminary ciphertext carriers; the determination process of each copy of the final ciphertext carrier is: selecting the preliminary ciphertext carriers of a second preset number, and encrypting the preliminary ciphertext carriers of the second preset number according to the encryption key and the secret sharing encryption algorithm to obtain the final ciphertext carrier; the number of the second preset number of copies is less than the number of the first preset number of copies.

[0023] Sending a plurality of copies of the final ciphertext carrier to a plurality of information hiding parties; the number of the information hiding parties is the same as the number of copies of the final ciphertext carrier.

[0024] Each of the information hiding parties is used to embed data into a copy of the final ciphertext carrier to obtain a secret-containing ciphertext carrier, and send the secret-containing ciphertext carrier to a receiving party.

[0025] The receiver is used to extract data and recover the carrier based on the encrypted ciphertext carrier of the third preset number to obtain the embedded data and the plaintext carrier; the number of the third preset number of copies is equal to the number of the first preset number of copies minus the number of the second preset number of copies plus 1.

[0026] According to the specific embodiments provided in this application, this application has the following technical effects:

[0027] The present application provides a shared domain reversible information hiding method and system based on re-encryption. First, a plaintext carrier is encrypted according to an encryption key and a secret sharing encryption algorithm to obtain several preliminary ciphertext carriers; then, the several preliminary ciphertext carriers are encrypted according to the encryption key and the secret sharing encryption algorithm to obtain several final ciphertext carriers; wherein, the determination process of each of the final ciphertext carriers is: a second preset number of preliminary ciphertext carriers are selected, and the second preset number of preliminary ciphertext carriers are encrypted according to the encryption key and the secret sharing encryption algorithm to obtain a final ciphertext carrier; finally, the several final ciphertext carriers are sent to several information hiding parties. The present application uses the above-mentioned technical solution of double encryption (i.e., re-encryption) to ensure that each information hiding party receives a final ciphertext carrier containing a second preset number of preliminary ciphertext carrier information. Compared with the prior art method of using one-time encryption, each information hiding party receives a ciphertext carrier containing only one ciphertext carrier information. The present application can effectively reduce the difficulty for the information hiding party to embed data into the ciphertext carrier; moreover, in the present application, the value of the second preset number can be adjusted as needed during the generation process of the ciphertext carrier to balance the difficulty of data embedding and the amount of data in each final ciphertext carrier. BRIEF DESCRIPTION OF THE DRAWINGS

[0028] In order to more clearly illustrate the embodiments of the present application or the technical solutions in the prior art, the following briefly introduces the drawings required for use in the embodiments. Obviously, the drawings described below are only some embodiments of the present application. For ordinary technicians in this field, other drawings can be obtained based on these drawings without creative work.

[0029] Figure 1 A flowchart of a re-encryption-based shared domain reversible information hiding method provided in one embodiment of the present application;

[0030] Figure 2 A schematic diagram of a re-encryption-based shared domain reversible information hiding system provided in one embodiment of the present application;

[0031] Figure 3 A schematic diagram of a reversible information hiding model in a shared domain based on re-encryption provided in one embodiment of the present application;

[0032] Figure 4 A schematic diagram of the structure of a computer device provided in one embodiment of the present application. DETAILED DESCRIPTION

[0033] The following will be combined with the drawings in the embodiments of this application to clearly and completely describe the technical solutions in the embodiments of this application. Obviously, the embodiments described are only part of the embodiments of this application, not all of the embodiments. Based on the embodiments in this application, all other embodiments obtained by ordinary technicians in this field without making creative efforts are within the scope of protection of this application.

[0034] Currently, shared domain reversible information hiding has the following shortcomings:

[0035] (1) Ciphertext carriers are difficult to use directly for data embedding. The process of encrypting plaintext carriers into ciphertext carriers using a secure encryption algorithm destroys the correlation of the carriers, that is, the correlation of the plaintext carriers is dispersed into different ciphertext carriers; and the generated ciphertext carriers are held by different information hiding parties, that is, the ciphertext carriers cannot be used to embed data by performing ciphertext operations, which makes it difficult for the information hiding party to directly embed data into the ciphertext carrier.

[0036] (2) The generation of ciphertext carriers cannot be adjusted dynamically. The generation of ciphertext carriers is determined by the encryption algorithm and the plaintext carrier. When a specific encryption algorithm is used to encrypt the plaintext carrier, the generated ciphertext carrier is also determined, which in turn determines the dependency between information hiding and the ciphertext carrier.

[0037] In order to make the above-mentioned purposes, features and advantages of the present application more obvious and easy to understand, the present application is further described in detail below with reference to the accompanying drawings and specific implementation methods.

[0038] In an exemplary embodiment, Figure 1 As shown, the present application provides a shared domain reversible information hiding method based on re-encryption, comprising the following steps:

[0039] Step S101: Obtain a plaintext carrier.

[0040] Step S102: Encrypt the plaintext carrier according to the encryption key and the secret sharing encryption algorithm (hereinafter referred to as the secret sharing algorithm) to obtain a plurality of preliminary ciphertext carriers (hereinafter also referred to as ciphertext carriers); wherein, a first preset number of the preliminary ciphertext carriers are used to restore the plaintext carrier; the number of the first preset number of the preliminary ciphertext carriers is greater than or equal to 2 and less than or equal to the number of the preliminary ciphertext carriers.

[0041] Step S103: Encrypt several copies of the preliminary ciphertext carriers according to the encryption key and the secret sharing encryption algorithm to obtain several copies of the final ciphertext carriers; wherein the number of copies of the final ciphertext carriers is the same as the number of copies of the preliminary ciphertext carriers; the determination process of each copy of the final ciphertext carrier is: select the preliminary ciphertext carriers of a second preset number, and encrypt the preliminary ciphertext carriers of the second preset number according to the encryption key and the secret sharing encryption algorithm to obtain the final ciphertext carrier; the number of the second preset number of copies is less than the number of the first preset number of copies.

[0042] Step S102 and step S103 together constitute a re-encryption technology (re-encryption for short), also known as a double secret sharing re-encryption technology.

[0043] Step S104: Send several copies of the final ciphertext carrier to several information hiding parties; the number of the information hiding parties is the same as the number of copies of the final ciphertext carrier; each of the information hiding parties is used to embed data into a copy of the final ciphertext carrier to obtain a secret ciphertext carrier, and send the secret ciphertext carrier to a receiving party; the receiving party is used to extract data and recover the carrier according to a third preset number of secret ciphertext carriers to obtain the embedded data and the plaintext carrier; the number of the third preset number of copies is equal to the number of the first preset number of copies minus the number of the second preset number of copies plus 1.

[0044] As an optional implementation, the process of determining each final ciphertext carrier is as follows:

[0045] The final ciphertext carrier is determined using the following mathematical model:

[0046] ;

[0047] in, Indicates the The final ciphertext carrier; represents the secret sharing encryption algorithm; Represents the encryption key; A preliminary ciphertext carrier representing a second predetermined number of copies; Indicates the A preliminary ciphertext carrier; ; Indicates modulus; Indicates the second preset number of copies; Indicates the number of copies of the final ciphertext carrier, which is also the number of copies of the preliminary ciphertext carrier.

[0048] In this embodiment, in terms of data embedding into a copy of the final ciphertext carrier, the operations performed by the information hiding party specifically include:

[0049] According to the hidden key and the embedded data, the final ciphertext carrier is embedded with data using a ciphertext operation embedding algorithm to obtain the secret-containing ciphertext carrier.

[0050] Furthermore, in extracting data from the third preset number of ciphertext carriers to obtain embedded data, the operations performed by the recipient specifically include:

[0051] According to the hidden key, a ciphertext operation extraction algorithm is used to extract data from each of the encrypted ciphertext carriers to obtain the embedded data corresponding to each of the encrypted ciphertext carriers.

[0052] In this embodiment, in terms of recovering the plaintext carriers from the third preset number of ciphertext carriers, the operations performed by the receiver specifically include:

[0053] According to the decryption key and the secret sharing decryption algorithm, a decryption operation is performed on the third preset number of the secret-containing ciphertext carriers to obtain the fourth preset number of the preliminary ciphertext carriers; the fourth preset number is greater than or equal to the first preset number; wherein, in the fourth preset number of preliminary ciphertext carriers, each preliminary ciphertext carrier is different from other preliminary ciphertext carriers.

[0054] A first preset number of the preliminary ciphertext carriers are selected from a fourth preset number of the preliminary ciphertext carriers.

[0055] According to the decryption key and the secret sharing decryption algorithm, a decryption operation is performed on the first preset number of preliminary ciphertext carriers to obtain the plaintext carriers.

[0056] That is, the receiver recovers the plaintext carrier through the above-mentioned double secret sharing decryption technology.

[0057] As an optional implementation, the secret sharing encryption algorithm includes a Shamir threshold secret sharing encryption algorithm and a secret sharing encryption algorithm based on the Chinese remainder theorem.

[0058] Furthermore, when the secret sharing encryption algorithm is the Shamir threshold secret sharing encryption algorithm, the secret sharing decryption algorithm is the Lagrange polynomial interpolation algorithm. When the secret sharing encryption algorithm is the secret sharing encryption algorithm based on the Chinese remainder theorem, the secret sharing decryption algorithm is the congruence equation solution algorithm.

[0059] In another exemplary embodiment of the present application, another shared domain reversible information hiding method based on re-encryption is provided, comprising the following steps:

[0060] Step S201: The encryption party obtains the plaintext carrier.

[0061] Step S202: The encryption party encrypts the plaintext carrier according to the encryption key and the secret sharing encryption algorithm to obtain a number of preliminary ciphertext carriers; wherein, a first preset number of the preliminary ciphertext carriers are used to restore the plaintext carrier; the number of the first preset number of copies is greater than or equal to 2 and less than or equal to the number of the preliminary ciphertext carriers.

[0062] Step S203: The encrypting party encrypts several copies of the preliminary ciphertext carriers according to the encryption key and the secret sharing encryption algorithm to obtain several copies of the final ciphertext carriers; wherein the number of the final ciphertext carriers is the same as the number of the preliminary ciphertext carriers; the determination process of each of the final ciphertext carriers is: selecting the preliminary ciphertext carriers of a second preset number, and encrypting the preliminary ciphertext carriers of the second preset number according to the encryption key and the secret sharing encryption algorithm to obtain the final ciphertext carrier; the number of the second preset number of copies is less than the number of the first preset number of copies.

[0063] Step S204: the encryption party sends several copies of the final ciphertext carrier to several information hiding parties; the number of the information hiding parties is the same as the number of copies of the final ciphertext carrier.

[0064] Step S205: Each of the information hiding parties embeds data into a copy of the final ciphertext carrier to obtain a secret-containing ciphertext carrier, and sends the secret-containing ciphertext carrier to a receiving party.

[0065] Step S206: The receiver extracts data and recovers the encrypted carrier according to the third preset number of encrypted ciphertext carriers to obtain the embedded data and the plaintext carrier; the number of the third preset number of copies is equal to the number of the first preset number of copies minus the number of the second preset number of copies plus 1.

[0066] Based on the same inventive concept, the embodiments of the present application also provide a re-encrypted shared domain reversible information hiding system for implementing the re-encrypted shared domain reversible information hiding method mentioned above. The implementation solution provided by this system is similar to the implementation solution described in the above method. Therefore, the specific limitations of one or more embodiments of the re-encrypted shared domain reversible information hiding system provided below can be found in the limitations of the re-encrypted shared domain reversible information hiding method mentioned above, and will not be repeated here.

[0067] In an exemplary embodiment, Figure 2 As shown, a shared domain reversible information hiding system based on re-encryption is provided, comprising:

[0068] The encryption method M1 is used to:

[0069] Get the plaintext carrier.

[0070] The plaintext carrier is encrypted according to the encryption key and the secret sharing encryption algorithm to obtain a plurality of preliminary ciphertext carriers; wherein a first preset number of the preliminary ciphertext carriers are used to restore the plaintext carrier; the number of the first preset number of the preliminary ciphertext carriers is greater than or equal to 2 and less than or equal to the number of the preliminary ciphertext carriers.

[0071] According to the encryption key and the secret sharing encryption algorithm, several copies of the preliminary ciphertext carriers are encrypted to obtain several copies of the final ciphertext carriers; wherein the number of copies of the final ciphertext carriers is the same as the number of copies of the preliminary ciphertext carriers; the determination process of each copy of the final ciphertext carrier is: selecting the preliminary ciphertext carriers of a second preset number, and encrypting the preliminary ciphertext carriers of the second preset number according to the encryption key and the secret sharing encryption algorithm to obtain the final ciphertext carrier; the number of the second preset number of copies is less than the number of the first preset number of copies.

[0072] Send several copies of the final ciphertext carrier to several information hiding parties M2; the number of the information hiding parties is the same as the number of copies of the final ciphertext carrier.

[0073] Each of the information hiding parties M2 is configured to perform data embedding on a copy of the final ciphertext carrier to obtain a secret-containing ciphertext carrier, and send the secret-containing ciphertext carrier to a receiving party M3.

[0074] The receiver M3 is used to extract data and recover the carrier based on the encrypted ciphertext carrier of the third preset number to obtain the embedded data and the plaintext carrier; the number of the third preset number of copies is equal to the number of the first preset number of copies minus the number of the second preset number of copies plus 1.

[0075] In another exemplary embodiment, the encryption party is the owner of the plaintext carrier (hereinafter referred to as the owner). In this embodiment, the shared domain reversible information hiding system based on re-encryption is also referred to as a shared domain reversible information hiding model based on re-encryption. That is, the model consists of carrier encryption, data embedding, data extraction, and carrier recovery, which are performed by the owner, information hiding party, and receiver respectively. Figure 3 .

[0076] In the carrier encryption process, all parties use the double secret sharing re-encryption technology based on the encryption key to encrypt the plaintext carrier into multiple final ciphertext carriers. The generated multiple final ciphertext carriers are sent to multiple different information hiding parties for data embedding. Specifically, all parties first use the secret sharing algorithm to encrypt the plaintext carrier into A ciphertext carrier, where A ciphertext carrier can restore the plaintext carrier. , the mathematical expression of the secret sharing encryption process is as follows:

[0077] ;

[0078] in, To use encryption keys Secret sharing algorithm, For generated The secret sharing algorithm here can be selected from Shamir threshold secret sharing algorithm, secret sharing algorithm based on Chinese remainder theorem, etc. Then select A secure number of ciphertext carriers are used as input and encrypted again using the secret sharing algorithm to generate The final ciphertext carrier. Ciphertext carrier , its secret sharing encryption process can be found in the previous embodiment. The final ciphertext carrier is sent to Different information hiding methods are used for data embedding.

[0079] In the data embedding process, each information hiding party embeds the data into the final ciphertext carrier according to the hidden key to generate a secret ciphertext carrier (to achieve data embedding), and authorizes part of the secret ciphertext carrier to the receiver for data extraction and carrier recovery. Final ciphertext carrier The data is For the final ciphertext carrier , the mathematical expression of data embedding is as follows:

[0080] ;

[0081] in, Indicates the A hidden key, represents the ciphertext operation embedding algorithm using a hidden key, Indicates the generated A ciphertext carrier.

[0082] During the data extraction and carrier recovery process, the receiver selects a sufficient number of ciphertext carriers to perform data extraction and carrier recovery. On the one hand, the receiver uses the hidden key and ciphertext operations to extract the embedded data; on the other hand, the receiver uses the decryption key and double secret sharing to decrypt and recover the plaintext carrier.

[0083] During data extraction and carrier recovery, the receiver needs to use any The plaintext carrier can only be restored by copying the ciphertext carrier. Since each ciphertext carrier contains The information of the ciphertext carrier can be selected by The encrypted ciphertext carrier is used to recover the plaintext carrier and extract the data embedded in it. The encrypted ciphertext carrier is For data extraction, the receiver uses the ciphertext extraction algorithm to extract the embedded data from the ciphertext carrier. Its mathematical expression is as follows:

[0084] ;

[0085] in, Indicates the use of hidden keys The ciphertext operation extraction algorithm, For the extracted data, For carrier recovery, the receiver first performs secret shared decryption on the encrypted ciphertext carrier to obtain the ciphertext carrier, which is mathematically expressed as follows:

[0086] ;

[0087] in, Indicates the use of decryption key Secret sharing decryption algorithm, Generated for decryption Second, the receiver decrypts the generated Perform secret shared decryption on the ciphertext carrier to recover the plaintext carrier , its mathematical expression is as follows:

[0088] .

[0089] If the Shamir threshold secret sharing algorithm is used to encrypt the plaintext carrier during the carrier encryption process, then the corresponding secret sharing decryption algorithm is Lagrange polynomial interpolation; if the secret sharing algorithm based on the Chinese remainder theorem is used to encrypt the plaintext carrier during the carrier encryption process, then the corresponding secret sharing decryption algorithm is to solve the congruence equation.

[0090] To facilitate understanding of the above process, the following example further illustrates it:

[0091] For plaintext carriers , after the first encryption, we get 10 (i.e. ) copies of (preliminary) ciphertext carriers; among them, any 5 (i.e. ) ciphertext carriers can be used to recover the plaintext carrier. In the second encryption, each final ciphertext carrier is based on any 3 (i.e. ) ciphertext carriers are generated; for example, the first final ciphertext carrier is generated based on the 1st to 3rd ciphertext carriers, the second final ciphertext carrier is generated based on the 2nd to 4th ciphertext carriers, ..., the tenth final ciphertext carrier is generated based on the 10th-2nd (i.e., the 10th, 1st, and 2nd) ciphertext carriers.

[0092] Each information hiding party embeds data into a final ciphertext carrier to obtain a corresponding secret-containing ciphertext carrier; for example, the first information hiding party embeds data into the first final ciphertext carrier to obtain the first secret-containing ciphertext carrier, the second information hiding party embeds data into the second final ciphertext carrier to obtain the second secret-containing ciphertext carrier, ..., the tenth information hiding party embeds data into the tenth final ciphertext carrier to obtain the tenth secret-containing ciphertext carrier.

[0093] The receiver can be based on any 3 (i.e. ) encrypted ciphertext carriers to extract data or recover the carriers; for example, for the 1st to 3rd encrypted ciphertext carriers, on the one hand, data is extracted respectively to obtain the corresponding data; on the other hand, decryption is performed based on the decryption key and the 1st to 3rd encrypted ciphertext carriers to obtain the 1st to 5th ciphertext carriers, and then the plaintext carriers are recovered based on the 1st to 5th ciphertext carriers Of course, if it is other situations, such as for the 1st, 3rd, and 5th ciphertext carriers, we can get the 1st to 7th ciphertext carriers, and then choose any 5 ciphertext carriers from the 1st to 7th ciphertext carriers to restore the plaintext carrier. .

[0094] This application has the following beneficial effects:

[0095] (1) The ciphertext carrier is easy to embed data. Under the condition of ensuring security, the final ciphertext carrier generated by each double secret sharing encryption is sent to a single information hiding party, that is, each information hiding party can independently perform ciphertext operations on the corresponding final ciphertext carrier, which makes it easy for each information hiding party to embed data into the ciphertext carrier. For each information hiding party, the more plaintext carrier information its ciphertext carrier for data embedding (corresponding to the final ciphertext carrier of this application) contains, the easier it is to embed data. In this application, during the second encryption, each final ciphertext carrier obtained is based on It is generated by a ciphertext carrier, so it contains more plaintext carrier information, which can effectively reduce the difficulty of data embedding.

[0096] (2) Adaptive ciphertext carrier control. In the double secret sharing encryption process, the generation of the final ciphertext carrier is adaptively controlled by dynamically adjusting the input parameters. That is, by selecting A secure number of ciphertext carriers are used as input and encrypted again using the secret sharing algorithm to generate The final ciphertext carrier. The input parameter refers to A secure number of ciphertext carriers, where Can be adjusted dynamically to select different parameters will produce different final ciphertext carriers. However, The larger the value of , the larger the amount of data in each final ciphertext carrier.

[0097] It can also be understood as follows: the ciphertext carrier in the existing method is determined by the input (plaintext carrier) and the encryption algorithm; the re-encryption technology used in this method changes the input, that is, the plaintext carrier becomes The number of secure ciphertext carriers can be adjusted dynamically, so the final ciphertext carrier output will also change.

[0098] In an exemplary embodiment, a computer device is provided. The computer device may be a server or a terminal. The internal structure diagram thereof may be as follows: Figure 4 As shown. The computer device includes a processor, a memory, an input / output interface (Input / Output, abbreviated as I / O) and a communication interface. The processor, memory and input / output interface are connected through a system bus, and the communication interface is connected to the system bus through the input / output interface. The processor of the computer device is used to provide computing and control capabilities. The memory of the computer device includes a non-volatile storage medium and an internal memory. The non-volatile storage medium stores an operating system, a computer program and a database. The internal memory provides an environment for the operation of the operating system and computer program in the non-volatile storage medium. The database of the computer device is used to store plaintext carrier data. The input / output interface of the computer device is used to exchange information between the processor and an external device. The communication interface of the computer device is used to communicate with an external terminal through a network connection. When the computer program is executed by the processor, a shared domain reversible information hiding method based on re-encryption is implemented.

[0099] Those skilled in the art will understand that Figure 4 The structure shown in the figure is merely a block diagram of a portion of the structure related to the solution of the present application and does not constitute a limitation on the computer device to which the solution of the present application is applied. A specific computer device may include more or fewer components than shown in the figure, or combine certain components, or have a different component arrangement. In an exemplary embodiment, a computer device is provided, including a memory and a processor. The memory stores a computer program, and the processor implements the steps of the above-mentioned method embodiments when executing the computer program.

[0100] In an exemplary embodiment, a computer-readable storage medium is provided, storing a computer program. When the computer program is executed by a processor, a re-encryption-based shared domain reversible information hiding method is implemented.

[0101] In an exemplary embodiment, a computer program product is provided, including a computer program. When the computer program is executed by a processor, a shared domain reversible information hiding method based on re-encryption is implemented.

[0102] It should be noted that the user information (including but not limited to user device information, user personal information, etc.) and data (including but not limited to data used for analysis, stored data, displayed data, etc.) involved in this application are all information and data authorized by the user or fully authorized by all parties, and the collection, use and processing of relevant data must comply with relevant regulations.

[0103] Those skilled in the art will appreciate that all or part of the processes in the above-mentioned embodiments can be implemented by instructing the relevant hardware through a computer program. The computer program can be stored in a non-volatile computer-readable storage medium. When the computer program is executed, it can include the processes of the above-mentioned embodiments. In particular, any reference to memory, database, or other media used in the embodiments provided in this application can include at least one of non-volatile and volatile memory. Non-volatile memory can include read-only memory (ROM), magnetic tape, floppy disk, flash memory, optical memory, high-density embedded non-volatile memory, resistive random access memory (ReRAM), magnetic random access memory (MRAM), ferroelectric random access memory (FRAM), phase change memory (PCM), graphene memory, etc. Volatile memory can include random access memory (RAM) or external cache memory, etc. By way of illustration and not limitation, RAM may be in various forms, such as static random access memory (SRAM) or dynamic random access memory (DRAM).

[0104] The databases involved in the various embodiments provided herein may include at least one of a relational database and a non-relational database. Non-relational databases may include, but are not limited to, distributed databases based on blockchains. The processors involved in the various embodiments provided herein may include, but are not limited to, general-purpose processors, central processing units, graphics processing units, digital signal processors, programmable logic units, data processing logic units based on quantum computing, and the like.

[0105] The technical features of the above embodiments can be combined arbitrarily. To make the description concise, not all possible combinations of the technical features in the above embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.

[0106] This document uses specific examples to illustrate the principles and implementation methods of this application. The description of the above examples is only intended to help understand the method and core concept of this application. At the same time, for those skilled in the art, based on the concept of this application, there may be changes in the specific implementation methods and application scope. In summary, the content of this specification should not be understood as limiting this application.

Claims

1. A re-encryption-based shared domain reversible information hiding method, characterized in that: The re-encryption-based shared domain reversible information hiding method includes: Obtaining plaintext carrier; Encrypting the plaintext carrier according to an encryption key and a secret sharing encryption algorithm to obtain a plurality of preliminary ciphertext carriers; wherein a first predetermined number of the preliminary ciphertext carriers are used to restore the plaintext carrier; the first predetermined number of the preliminary ciphertext carriers is greater than or equal to 2 and less than or equal to the number of the preliminary ciphertext carriers; Encrypting a plurality of the preliminary ciphertext carriers according to the encryption key and the secret sharing encryption algorithm to obtain a plurality of final ciphertext carriers; wherein the number of the final ciphertext carriers is the same as the number of the preliminary ciphertext carriers; and determining each of the final ciphertext carriers by selecting a second preset number of the preliminary ciphertext carriers and encrypting the second preset number of the preliminary ciphertext carriers according to the encryption key and the secret sharing encryption algorithm to obtain the final ciphertext carrier; the second preset number of the copies being less than the first preset number of the copies; Several copies of the final ciphertext carrier are sent to several information hiding parties; the number of the information hiding parties is the same as the number of copies of the final ciphertext carrier; each of the information hiding parties is used to embed data into a copy of the final ciphertext carrier to obtain a secret ciphertext carrier, and send the secret ciphertext carrier to a receiving party; the receiving party is used to extract data and recover the carrier based on a third preset number of secret ciphertext carriers to obtain the embedded data and the plaintext carrier; the number of the third preset number of copies is equal to the number of the first preset number of copies minus the number of the second preset number of copies plus 1.

2. The re-encryption-based shared domain reversible information hiding method according to claim 1, characterized in that: The process of determining each final ciphertext carrier is as follows: The final ciphertext carrier is determined using the following mathematical model: ； in, Indicates the The final ciphertext carrier; represents the secret sharing encryption algorithm; Represents the encryption key; A preliminary ciphertext carrier representing a second predetermined number of copies; Indicates the A preliminary ciphertext carrier; Indicates the A preliminary ciphertext carrier; Indicates the A preliminary ciphertext carrier; Indicates the A preliminary ciphertext carrier; ; Indicates modulus; Indicates the second preset number of copies; Indicates the number of copies of the final ciphertext carrier.

3. The re-encryption-based shared domain reversible information hiding method according to claim 1, characterized in that: In terms of data embedding into a copy of the final ciphertext carrier, the operations performed by the information hiding party specifically include: According to the hidden key and the embedded data, the final ciphertext carrier is embedded with data using a ciphertext operation embedding algorithm to obtain the secret-containing ciphertext carrier.

4. The re-encryption-based shared domain reversible information hiding method according to claim 3, characterized in that: In terms of extracting data from the third preset number of ciphertext carriers to obtain embedded data, the operations performed by the receiving party specifically include: According to the hidden key, a ciphertext operation extraction algorithm is used to extract data from each of the encrypted ciphertext carriers to obtain the embedded data corresponding to each of the encrypted ciphertext carriers.

5. The re-encryption-based shared domain reversible information hiding method according to claim 1, characterized in that: In terms of recovering the plaintext carriers from the encrypted ciphertext carriers of the third preset number, the operations performed by the receiving party specifically include: performing a decryption operation on a third preset number of the secret-containing ciphertext carriers according to a decryption key and a secret sharing decryption algorithm to obtain a fourth preset number of the preliminary ciphertext carriers; the fourth preset number of the preliminary ciphertext carriers being greater than or equal to the first preset number of the preliminary ciphertext carriers; Selecting a first preset number of the preliminary ciphertext carriers from a fourth preset number of the preliminary ciphertext carriers; According to the decryption key and the secret sharing decryption algorithm, a decryption operation is performed on the first preset number of preliminary ciphertext carriers to obtain the plaintext carriers.

6. The re-encryption-based shared domain reversible information hiding method according to claim 5, characterized in that: The secret sharing encryption algorithm includes the Shamir threshold secret sharing encryption algorithm and the secret sharing encryption algorithm based on the Chinese remainder theorem.

7. The re-encryption-based shared domain reversible information hiding method according to claim 6, characterized in that: When the secret sharing encryption algorithm is the Shamir threshold secret sharing encryption algorithm, the secret sharing decryption algorithm is the Lagrange polynomial interpolation algorithm.

8. The re-encryption-based shared domain reversible information hiding method according to claim 6, characterized in that: When the secret sharing encryption algorithm is a secret sharing encryption algorithm based on the Chinese remainder theorem, the secret sharing decryption algorithm is an algorithm for solving congruence equations.

9. A re-encryption-based shared domain reversible information hiding method, characterized in that: The re-encryption-based shared domain reversible information hiding method includes: The encryption party obtains the plaintext carrier; The encryption party encrypts the plaintext carrier according to the encryption key and the secret sharing encryption algorithm to obtain a plurality of preliminary ciphertext carriers; wherein a first preset number of the preliminary ciphertext carriers are used to restore the plaintext carrier; the number of the first preset number of the copies is greater than or equal to 2 and less than or equal to the number of the preliminary ciphertext carriers; The encryption party encrypts the plurality of preliminary ciphertext carriers according to the encryption key and the secret sharing encryption algorithm to obtain a plurality of final ciphertext carriers; wherein the number of the final ciphertext carriers is the same as the number of the preliminary ciphertext carriers; and each final ciphertext carrier is determined by selecting a second preset number of preliminary ciphertext carriers and encrypting the second preset number of preliminary ciphertext carriers according to the encryption key and the secret sharing encryption algorithm to obtain the final ciphertext carrier; the second preset number of copies is less than the first preset number of copies; The encryption party sends a plurality of copies of the final ciphertext carrier to a plurality of information hiding parties; the number of the information hiding parties is the same as the number of copies of the final ciphertext carrier; Each of the information hiding parties embeds data into a copy of the final ciphertext carrier to obtain a ciphertext carrier containing secrets, and sends the ciphertext carrier containing secrets to a receiving party; The receiver extracts data and recovers the encrypted carrier based on the third preset number of encrypted ciphertext carriers to obtain the embedded data and the plaintext carrier; the number of the third preset number of copies is equal to the number of the first preset number of copies minus the number of the second preset number of copies plus 1.

10. A re-encryption-based shared domain reversible information hiding system, characterized in that: The re-encryption-based shared domain reversible information hiding system includes: Encryption parties are used to: Obtaining the plaintext carrier; Encrypting the plaintext carrier according to an encryption key and a secret sharing encryption algorithm to obtain a plurality of preliminary ciphertext carriers; wherein a first predetermined number of the preliminary ciphertext carriers are used to restore the plaintext carrier; the first predetermined number of the preliminary ciphertext carriers is greater than or equal to 2 and less than or equal to the number of the preliminary ciphertext carriers; Encrypting a plurality of the preliminary ciphertext carriers according to the encryption key and the secret sharing encryption algorithm to obtain a plurality of final ciphertext carriers; wherein the number of the final ciphertext carriers is the same as the number of the preliminary ciphertext carriers; and determining each of the final ciphertext carriers by selecting a second preset number of the preliminary ciphertext carriers and encrypting the second preset number of the preliminary ciphertext carriers according to the encryption key and the secret sharing encryption algorithm to obtain the final ciphertext carrier; the second preset number of the copies being less than the first preset number of the copies; Sending a plurality of copies of the final ciphertext carrier to a plurality of information hiding parties; the number of the information hiding parties is the same as the number of copies of the final ciphertext carrier; Each of the information hiding parties is configured to embed data into a copy of the final ciphertext carrier to obtain a ciphertext carrier containing secrets, and send the ciphertext carrier containing secrets to a receiving party; The receiver is used to extract data and recover the carrier based on the encrypted ciphertext carrier of the third preset number to obtain the embedded data and the plaintext carrier; the number of the third preset number of copies is equal to the number of the first preset number of copies minus the number of the second preset number of copies plus 1.

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