WO2023204678A1

WO2023204678A1 - Encryption system and method using media content file of sender or receiver

Info

Publication number: WO2023204678A1
Application number: PCT/KR2023/005488
Authority: WO
Inventors: 정희성
Original assignee: 주식회사 네오패드
Priority date: 2022-04-21
Filing date: 2023-04-21
Publication date: 2023-10-26
Also published as: KR102564618B1

Abstract

The present invention provides an encryption system and method that uses a media content file created and stored in a sender's or receiver's device as an encryption key for the sender's plaintext, an encryption key for common key distribution, and a decryption key for the media content file that is an encryption target of the sender and the receiver. The present invention provides an encryption system and method that not only addresses the key distribution problem and facilitates key generation and management on the basis of common key cryptography, but also guarantees information-theoretic security of a generated cipher. The present invention provides a more user-friendly encryption system and method by enabling a sender and a receiver to easily select plain text and encryption and decryption keys for an object to be encrypted on a smartphone or the like.

Description

Encryption system and method using media content files of sender or receiver

The present invention is an encryption system and method that can be installed on various information devices.

As the number of devices connected to the Internet increases exponentially, security issues regarding connected devices and the information and data exchanged between devices will become a serious technical challenge in the future. Encryption technology is also becoming more important in the new commerce market, that is, in the virtual space represented by the metaverse, the authenticity of commerce items, and item trading in NFT games.

Additionally, as numerous confidential data are stored on remote computer servers such as the cloud, protection technology for data on the network is becoming more important. The safety of data communication as described above depends on the encryption method of information transmitted and received over the network.

Current cryptographic communication technologies use complex formulas and guarantee the computational safety of cryptography based on the so-called computational complexity, which means that it takes a huge amount of time to solve these formulas. In addition, post-quantum cryptography and quantum key delivery methods are known as representative next-generation technologies.

Data related to background technology are as follows.

(Patent Document 1) 1. US 11,233,628 Equivocation augmentation dynamic secrecy system

(Patent Document 2) 2. US 11,177,959 Cryptography method and system for securing data via electronic transmission

(Patent Document 3) 3. US 11,176,624 Privacy-preserving smart metering

(Patent Document 4) 4. US 11,165,563 Symmetric key stream cipher cryptographic method and device

(Patent Document 5) 5. US 11,095,442 Generating unique cryptographic keys from a pool of random elements

(Patent Document 6) 6. US 10,873,448 Technique to generate symmetric encryption algorithms

(Patent Document 7) 7. US 10,348,704 Method for a dynamic perpetual encryption cryptosystem

(Patent Document 8) 8. US 10,263,785 Cryptography method and system for securing data via electronic transmission

(Patent Document 9) 9. US 10,069,805 Polymorphic one time pad matrix

(Patent Document 10) 10. US 9,032,208 Communication terminal, communication system, communication method and communication program

(Patent Document 11) 11. US 9,001,998 Data encryption and decryption method and apparatus

(Patent Document 12) 12. US 8,948,377 Encryption device, encryption system, encryption method, and encryption program

(Patent Document 13) 13. US 8,942,373 Data encryption and decryption method and apparatus

(Patent Document 14) 14. US 8,824,686 Cluster key synchronization

(Patent Document 15) 15. US 8,611,542 Peer to peer key synchronization

(Patent Document 16) 16. US 8,607,046 System and method for signing a message to provide one-time approval to a plurality of parties

(Patent Document 17) 17. US 8,401,186 Cloud storage data access method, apparatus and system based on OTP

(Patent Document 18) 18. US 8,249,255 System and method for securing communications between devices

(Patent Document 19) 19. US 7,971,234 Method and apparatus for offline cryptographic key establishment

(Patent Document 20) 20. US 7,945,075 Converting a digital image from color to gray-scale

The purpose of the present invention is to provide encryption technology that provides security in the exchange and transaction of valuable data in the above-mentioned technology demanding environment.

The present invention provides a new encryption system and method that has information theoretic security, is easy to use, is simple, and is economical.

The present invention provides an encryption system and method that uses a media content file created and stored in the sender's or receiver's device as a plaintext encryption key, a common key delivery key, and a decryption key for media content files that are subject to encryption by the sender and receiver.

The present invention provides a more user-friendly encryption system and method by enabling senders and receivers to easily and selectively select encryption targets, encryption, and decryption keys on smartphones, etc.

The present invention provides a common key-based encryption system and method that is fast and has low key sharing costs in devices such as smartphones.

An encryption system using a sender's or receiver's media content file according to an embodiment of the present invention, which aims to solve the above technical problems, consists of the following structure.

The present invention relates to an encryption system on a sender or receiver device connected to a network, wherein the sender or receiver device includes one or more of a smartphone, tablet, smart watch, PC, CCTV, GPS, and a sensor device, and the sender device is a sender. It is provided with a memory means that can store the plain text that is the object of encryption.

The plain text, which is the subject of the sender's encryption, includes means for including content files such as text files, photo image files, audio files, and video files.

It is provided with means for generating an encrypted text of the sender's plaintext using a content file provided by the receiver or the sender as an encryption key for the plaintext that is the subject of the sender's encryption.

The content file used as the encryption key of the sender or receiver includes at least one of a text file of character data, a photo, a graphic image, an audio and a video file.

The sender's plaintext ciphertext is provided with a means for generating the bit string of the sender's plaintext file and the bit string of the content file provided by the receiver or sender by exclusive ORing.

It is provided with means for transmitting the generated ciphertext of the sender's plaintext to the recipient's device.

The recipient who has received the ciphertext of the sender's plaintext is equipped with means to decrypt the ciphertext of the sender's plaintext into plaintext using a content file provided by the sender or the receiver.

In addition, when the content file provided by the sender is used as an encryption key to generate the encrypted text of the sender's plaintext, the recipient who receives the encrypted text of the sender's plaintext uses the content file stored in the recipient's device as a public key for common key delivery. Provide the means to use .

The content file of the public key for delivering the common key to the recipient includes means including at least one of a text file of character data, a photo, a graphic image, an audio, and a video file.

The receiver is provided with means for transmitting the content file of the receiver to the sender device as a public key for delivering the common key.

The sender is equipped with a means for encrypting the sender's plain text encryption key using the receiver's content file, which is the public key for common key delivery sent by the receiver, and the sender's plain text encryption key.

It is provided with means for transmitting the ciphertext of the sender's plaintext encryption key encrypted by the sender to the recipient's device.

The recipient, who has received the ciphertext of the sender's plaintext encryption key, is provided with means for decrypting it with the sender's plaintext encryption key using a content file that is the recipient's common key delivery public key.

It further includes means for decrypting the sender's plaintext ciphertext into the sender's plaintext using the sender's plaintext encryption key decrypted by the receiver.

In addition, the means for the sender to encrypt the sender's plain text encryption key using the receiver's content file, which is the public key for common key delivery sent by the receiver, and the sender's plain text encryption key, is the means of encrypting the content file, which is the public key for common key delivery. This is done by calculating the exclusive OR of the bit string and the bit string of the sender's plaintext encryption key file.

In addition, the means for the recipient who has received the ciphertext of the sender's plaintext encryption key to decrypt it with the sender's plaintext encryption key using a content file that is the public key for delivery of the receiver's common key is to decrypt the ciphertext file of the received sender's plaintext encryption key. This is done by calculating the bit string and the bit string of the recipient's common key delivery public key file by exclusive OR.

In addition, the encryption system on the sender or receiver device connected to the network transmits the generated plaintext ciphertext of the sender to the receiver's device, and the receiver converts the received plaintext ciphertext of the sender into the public key for delivery of the receiver's common key. Select the corresponding media content file, calculate the bit string of the sender's plaintext ciphertext and the bit string of the recipient's public encryption key file by exclusive OR to create a combined file of the sender's plaintext ciphertext and the receiver's common key delivery public key of the same length. Provide the means to create

The bit string of the combined file of the common key delivery public key having the same length as the sender's ciphertext generated by the above procedure is calculated by exclusive OR with the bit string of the sender's plaintext ciphertext, and the receiver has the same length as the sender's ciphertext. A means for generating a public key for common key delivery is provided.

The public key file for delivery of the receiver's common key, which is created with the length of the sender's encryption key, is calculated by exclusive OR with the sender's plaintext encryption key on the sender's device, and a means is provided for generating a new file.

The newly created file is transmitted by the sender from the sender's device to the recipient's device and includes means for becoming a file that delivers the sender's plaintext encryption key.

The recipient, who has received the file delivering the sender's plain text encryption key, calculates the bit string of the file delivering the sender's plain text encryption key and the bit string of the public key file for delivering the receiver's common key by exclusive OR, and It is provided with a means to obtain the encryption key of the plaintext.

The receiver further includes means for obtaining the sender's plaintext by calculating the bit string of the received plaintext ciphertext of the sender and the bit string of the sender's plaintext encryption key file by exclusive OR.

In the encryption system on the sender or receiver device connected to the network of the present invention, the sender or receiver device includes one or more of a smartphone, tablet, PC, CCTV, and a smart watch, and the sender or receiver device is an audio or video encrypted call. Additional means may be provided.

A means of enabling an audio or video encrypted call of the device is that the sender or receiver selects the call mode, and before starting the call, the sender or receiver transmits a plain text encryption key to the other party, and at the same time sends the other party's plain text encryption key file and A means for exchanging secret keys is provided.

The plain text encryption key file of the other party is a content file of the recipient and includes at least one of a text file of character data, a photo, a graphic image, an audio, and a video file.

The sender or receiver is equipped with a means to generate the plain text encryption key file and the encrypted text of the secret key in their device and transmit it to the device of each call party.

The sender or receiver who receives the public key of the other party or exchanges the plain text encryption key and secret key is provided with a means for transmitting the plain text encryption key file and the encrypted text of the private key to the other party. .

The sender or receiver, who has received the plaintext encryption key file and the secret key encrypted text of the other party to the call, is provided with means to initiate a call after decrypting the encrypted text of the private key.

A means is provided for calculating the bit string of the call data of the sender or receiver and the bit string of the plaintext encryption key file of the sender or receiver by exclusive OR, and transmitting the calculation result as encrypted call data to the communication counterpart.

The sender or receiver, who has mutually received the bit string of the transmitted encryption currency data, is equipped with a means to decrypt the other party's encryption data using a plain text encryption key file and secret key information on his or her device.

In addition, the means for enabling audio or video encrypted calls of the device is that the sender or receiver selects the call mode and exchanges the public key of the sender or receiver, the plaintext encryption key file, and the encrypted text of the private key with the other party before starting the call. Provide means of transmission.

The sender or receiver who has received the public key, plaintext encryption key file, and encrypted text of the private key decrypts the encrypted text of the private key on his/her device, checks the encryption start point of the plaintext encryption key file, and completes the call reception status. It is provided with a means of transmitting and notifying information to the device of each caller.

The sender or receiver confirms the reception waiting state of the other party, and the calling party sets the encryption start point of his/her plain text encryption key file, and then is provided with means to initiate the encryption call.

Calculating the bit string of the call data of the calling party and the bit string of the plaintext encryption key file of the sender or receiver by exclusive OR to generate a cryptocurrency file, and transmitting the generated cryptocurrency data to the other party through the call line. Have the means.

The sender or receiver, who has mutually received the bit string of encrypted call data transmitted through the call line, is equipped with means to decrypt the other party's call encrypted text using the plaintext encrypted text file and secret key information on his or her device.

A means for confirming the encryption start point of the plaintext encryption key file and transmitting the completion of the call reception status to each caller's device to notify the other party's device, and The means for setting the encryption start point includes means that can be executed automatically by a software program or manually by the sender or receiver.

The encryption method using the media content file of the sender or receiver of the present invention is an encryption method on a sender or receiver device connected to a network, wherein the sender or receiver device is a smartphone, tablet, smart watch, PC, CCTV, GPS, and It includes one or more sensor devices, and the sender device is capable of storing plain text that is the subject of the sender's encryption, and the plain text that is the subject of the sender's encryption includes content files such as text files, photo image files, audio files, and video files, An encrypted text of the sender's plaintext is generated using a content file provided by the receiver or sender as an encryption key for the plaintext that is the object of encryption of the sender, and the content file used as the encryption key of the sender or receiver is at least a text file of character data, a photo, It includes at least one of a graphic image, audio, and video file, wherein the sender's plaintext ciphertext is encrypted using the content file provided by the receiver or the sender, and the sender's plaintext ciphertext is a bit string of the sender's plaintext file. The bit string of the content file provided by the receiver or sender is calculated and generated by exclusive OR, and the generated ciphertext of the sender's plaintext is transmitted to the recipient's device. The receiver who receives the ciphertext of the sender's plaintext is the sender or receiver. This is done by decrypting the sender's plaintext ciphertext into plaintext using a content file provided by .

In addition, in the case where the content file provided by the sender is used as a plaintext encryption key to generate the sender's plaintext ciphertext, the recipient who receives the ciphertext of the sender's plaintext stores the content stored in the recipient's device as a public key for common key delivery. Using a file, the content of the public key for delivery of the common key of the recipient includes at least one of a text file of character data, a photo, a graphic image, an audio, and a video file, and the public key for delivery of the common key to the recipient The content file of the recipient is transmitted to the sender device, and the sender encrypts the plaintext encryption key of the sender using the content file of the recipient, which is the public key for common key delivery sent by the recipient, and the plaintext encryption key of the sender, The sender transmits the encrypted text of the sender's plaintext encryption key to the recipient's device, and the recipient who receives the encrypted text of the sender's plaintext encryption key uses the content file, which is the public key for delivery of the receiver's common key, to the sender's device. Decryption is performed using a plaintext encryption key, and a method of decrypting the sender's plaintext ciphertext into the sender's plaintext using the sender's plaintext encryption key decrypted by the receiver is further provided.

In addition, a method of encrypting the sender's plain text encryption key using the receiver's content file, which is the public key for common key delivery sent by the receiver, and the sender's plain text encryption key is a method of encrypting the file bit string of the sender's plain text encryption key and the receiver's common key delivery. It is performed by calculating exclusive OR with the bit string of the public key file.

In addition, a method in which the sender encrypts the sender's plaintext encryption key using the receiver's content file, which is the public key for common key delivery sent by the receiver, and the sender's plaintext encryption key, is a bit of the content file, which is the public key for common key delivery. This is done by calculating the exclusive OR of the string and the bit string of the sender's plaintext encryption key file.

In addition, the encryption method on the sender or receiver device connected to the network of the present invention transmits the generated plaintext ciphertext of the sender to the receiver's device, and the receiver uses the received plaintext ciphertext of the sender for delivery of the receiver's common key. Select the media content file corresponding to the public key and calculate the bit string of the sender's plaintext ciphertext and the bit string of the recipient's common key delivery public key file by exclusive OR to obtain the recipient's common key delivery of the same length as the sender's plaintext ciphertext. A combination file of the public key is generated, and the bit string of the combination file of the receiver's common key delivery public key of the same length as the sender's ciphertext generated by the above procedure is calculated by exclusive ORing with the bit string of the sender's plaintext ciphertext. A public key for delivery of the receiver's common key that is equal to the length of the sender's encryption key is generated, and the public key file for delivery of the receiver's common key generated as the length of the sender's encryption key is stored in the sender's device as the sender's plaintext encryption. A new file is generated by calculating the key by exclusive OR, and the newly created file is transmitted by the sender from the sender's device to the receiver's device and becomes a file delivering the sender's plaintext encryption key, and the newly created file is transmitted by the sender from the sender's device to the receiver's device. The recipient who has received the file delivering the plaintext encryption key calculates the bit string of the file delivering the sender's plaintext encryption key and the bit string of the public key file for delivering the receiver's common key by exclusive OR to obtain the sender's plaintext. The method further includes obtaining an encryption key, and the receiver obtains the sender's plaintext by calculating an exclusive OR of a bit string of the received plaintext ciphertext of the sender and a bit string of the sender's plaintext encryption key file. The method of encrypting the sender's plain text encryption key using the receiver's content file, which is the public key for common key delivery sent by It is performed by calculating the bit string of the file by exclusive OR, and the sender encrypts the sender's plain text encryption key using the receiver's content file, which is the public key for common key delivery sent by the receiver, and the sender's plain text encryption key. This is done by calculating the bit string of the recipient content file, which is the public key for the common key delivery, and the bit string of the sender's plaintext encryption key file by exclusive OR, and the recipient who has received the encrypted text of the sender's plaintext encryption key is the recipient's The method of decrypting with the sender's plaintext encryption key using a content file that is a public key for common key delivery is a bit string of the ciphertext file of the sender's plaintext encryption key received by the receiver and a bit string of the public key file for common key delivery of the recipient. is calculated by exclusive OR, and in the encryption method on the sender or receiver device connected to the network of the present invention, the sender or receiver device includes one or more of a smartphone, tablet, PC, CCTV, and a smart watch, and the sender Or, the recipient device further includes a method of enabling an audio or video encrypted call, and the method of enabling the audio or video encrypted call of the device is that the sender or the recipient selects the call mode, and before starting the call, the sender or the recipient communicates with the other party. You can transmit a plain text encryption key file to the other party and at the same time exchange the plain text encryption key file and secret key of the other party, and the plain text encryption key file of the other party is the recipient's content file, such as a text file, photo, or graphic of character data. It includes at least one of an image, audio, and video file, and the sender or receiver can generate the plaintext encryption key file and the encrypted text of the secret key on their device and transmit it to each communication partner's device, and the communication partner's The sender or receiver who receives the public key or exchanges the plaintext encryption key and the secret key may transmit their plaintext encryption key file and the encrypted text of the secret key to the communication counterpart, and the communication counterpart's plaintext encryption key The sender or receiver who has received the file and the secret key encrypted text can initiate a call after decrypting the encrypted text of the private key, and the bit string of the call data of the sender or receiver and the plaintext encryption key file of the sender or receiver By calculating the bit string by exclusive OR, the calculation result can be transmitted to the communication counterpart as cryptocurrency data, and the sender or receiver who mutually receives the bit string of the transmitted cryptocurrency data can use the other party's cryptocurrency data as their own. It is done in a way that can be decrypted using a plain text encryption key file and secret key information on the device.

A method of enabling an audio or video encrypted call with the device is that the sender or receiver selects the call mode and exchanges the public key of the sender or receiver, the plaintext encryption key file, and the encrypted text of the private key to the other party before starting the call. The call counterpart's plain text encryption key file is a content file of the recipient and includes at least one of text files, photos, graphic images, audio, and video files of character data, and the public key, plain text encryption key file, and secret. The sender or receiver who has received the ciphertext of the key decrypts the ciphertext of the secret key on his or her own device, confirms the encryption start point of the plaintext encryption key file, and transmits and notifies the completion of the call reception status to each caller's device. , the sender or receiver confirms the reception waiting state of the other party, and the calling party sets the encryption start point of his/her plain text encryption key file, and then initiates the encryption call, and the bit string of the call data of the calling party A method of generating a cryptocurrency file by calculating the bit string of the plaintext encryption key file of the sender or the receiver by exclusive OR, and transmitting the generated cryptocurrency data to the other party of communication through a call line, wherein the call line The sender or receiver, who has mutually received the bit string of encrypted currency data transmitted via The method of confirming the encryption start point and transmitting the completion of the call reception status to each call party's device and setting the encryption start point can be performed automatically by a software program or manually by the sender or receiver. It consists of an encryption method equipped with a method.

The present invention constitutes an encryption system and encryption method using the above-described means and methods.

First, the encryption of the present invention provides information-theoretic secure encryption. Unlike existing random number generators and pseudo-random number generators, the seed for generating the encryption key of the present invention uses the multimedia content files of users such as the sender and receiver, so the security of the password is guaranteed. The user's multimedia content file is sufficiently random, unpredictable, and unreproducible, so its safety is guaranteed in information theory.

In addition, the security of the encryption of the present invention can be proven using the Shannon formula.

Second, the encryption of the present invention is an economical and user-friendly encryption because it generates an encryption key and performs key management using a multimedia content file that can be produced in everyday life without the introduction of an expensive random number generator in small devices such as smartphones. Services can be provided.

Third, the encryption of the present invention can flexibly respond to various multimedia information and data exchanged in the encryption technology required for sensor networks, NFT services, metaverse, autonomous vehicles, drones, telemedicine, etc., which will be established in the service market in the future. Encryption technology can be provided.

fourth. The cryptography of the present invention can provide a cryptographic system and method that can be flexibly used in the future despite technological innovations such as the emergence of quantum computers.

Fifth, the encryption of the present invention, unlike existing encryption methods, can provide an encryption system and method that allows the user to easily use the plain text of the multimedia content to be encrypted and the encryption key generated multimedia content on his or her own device. .

Sixth, the encryption of the present invention is a common key encryption method, which has fast processing speed and easy key management by specifying the number of keys to manage.

Seventh, a new world standard common key encryption method, ‘Neopad encryption’ can be proposed.

Figures 1 (a) and (b) show the infrastructure structure and network environment to which the encryption system and method of the present invention are applied.

Figure 2 shows an album menu of a smartphone indicating storage of media content files of the present invention.

Figures 3 and 4 show photo images that can be used as keys in the present invention and pixel coordinates of the encryption start point for generating a secret key.

Figure 5 is an example of a text file that can be used as a key of the present invention and shows an example of the matrix value of the character position of the start point and the character code value unicode.

Figure 6 shows RGB data for pixels of a photo image file.

Figure 7 shows an example of a bit string and encryption start point information of an audio file.

Figure 8 shows an example of bit string and encryption start point information of a video file.

Figure 9 shows a processing flowchart of Embodiment 1 of the present invention.

Figure 10 illustrates the result of generating a sender plaintext encryption file in an embodiment of the present invention.

Figure 11 is a flowchart showing the processing of Example 2 of the present invention.

Figure 12 is a flowchart showing the processing of Embodiment 3 of the present invention.

Figure 13 is a flowchart showing the processing of Example 5 of the present invention.

In the IOT environment where wireless communication, represented by 5G and 6G, and high-speed Internet are connected, security issues in communication, storage, and management of related information or data are a technical field that is more emphasized. In other words, in an IOT environment where various home appliances, medical devices, office equipment, industrial machinery, autonomous vehicles, drones, web cameras, etc. are hyper-connected, security encryption technology for data or information exchanged on the network and production and distribution in new commerce environments such as NFT are used. Information protection technology, which protects information and data, including the original data, from illegal cyber attacks by eavesdroppers, is a very important technology field.

The definitions of terms in the present invention are as follows. Encryption of data or information refers to a technology to hide one's data or information from others. In other words, encryption is a technology that prevents unauthorized people from reading or viewing information.

In the present invention, a person or device that transmits or sends information from an information device is defined as a sender. A person or device that receives the transmitted or sent information is defined as a receiver. In addition, the transmitted information is collectively defined as a message. If you want to prevent others from reading your outgoing messages, you must encrypt them. The message before encryption is called plaintext, and the message after encryption is called ciphertext. The purpose of encrypting the plaintext using cryptography is to protect the confidentiality of the plaintext. In order to read the encrypted ciphertext, the ciphertext must be converted back to plaintext, and this is called decryption. The encryption procedure is called the 'encryption algorithm', and the decryption procedure is called the 'decryption algorithm', and these two algorithms are collectively called the 'encryption algorithm'. An encryption key is required to convert the plaintext into ciphertext, and a decryption key is required to convert the ciphertext into plaintext. The plaintext, ciphertext, and key are called the three elements of a password.

In the present invention, reference is made to the definition of general terms related to encryption, but related terms are defined more broadly. In the present invention, the sender or receiver is, for example, an avatar who exchanges information in the metaverse world, the original owner or seller of the NFT, and the receiver is defined as the same concept as the manager or purchaser of the original NFT. Also, just as the transmitted information is called a message, in the present invention, everything that is subject to encryption is defined as plaintext. That is, the plain text may include a text data file, a photo or graphic image file, an audio file, a video file, or a multimedia file combining these files. Additionally, the cipherfile in the present invention has the same meaning as the ciphertext.

In the present invention, the types of information devices of the sender or receiver include information devices such as smartphones, tablets, PCs, and smart watches, and various sensors or devices such as CCTV and GPS, and the data output from the devices is numerical, It includes multimedia data that is a mixture of text, audio, video, etc. All data output from the above device is defined as plain text subject to encryption. Therefore, in the present invention, plaintext is defined to include not only the plaintext of existing encryption objects, but also all kinds of data or information related to drones, autonomous vehicles, sensor networks, games, NFTs, and the metaverse. do.

In the present invention, a person or device that seeks to access other people's data or information passing on a network such as the Internet with malicious intent for the purpose of wiretapping, modifying, or stealing is called an eavesdropper.

The purpose of the present invention is to provide an encryption method that is superior to the existing encryption method. In order to explain that the encryption system and method of the present invention are different from known encryption techniques, the known encryption method will be described.

The well-known encryption methods include symmetric key/common key encryption, public-key encryption, hybrid encryption, elliptic curve, and post-quantum encryption. It is widely known. Each of the above encryption methods uses a different encryption algorithm. Each encryption algorithm essentially uses a key.

(1)Common key/symmetric key encryption

The symmetric key encryption method is also called symmetric key encryption. The characteristic of the common key encryption method is that the same key is used in the encryption algorithm and decryption algorithm. A classic common key encryption method is the mechanical encryption method invented by G.S. Vernam (US. Patent 1,310,719).

(a)Vernam encryption algorithm and one-time pad encryption

vernam's encryption algorithm uses a logical calculation called exclusive OR in the plaintext encryption and ciphertext decryption algorithms.

Exclusive OR is a bit calculation operator that has the following calculation results.

a b ab

0 0 1

0 1 0

1 0 0

1 1 1

The calculation of the exclusive OR will be explained by applying it to an actual encryption algorithm. For example, try encrypting and decrypting the plaintext m = ” with the encryption key k = aa bb cc dd ee (hexadecimal).

Bit calculation of natural language data requires converting character codes into binary numbers, so if you convert the plain text to binary, the data becomes longer, so for convenience, if you convert it to hexadecimal,

m' = 68 65 6c 6c 6f.

If we calculate the exclusive OR (denoted by m' and k),

c = m' k = c2 de a0 b1 81 and c becomes the ciphertext. This ciphertext c is sent to the recipient.

After receiving the ciphertext c, the receiver calculates the exclusive OR of c with k again. As a result of the calculation, m' can be obtained, where m' is the hexadecimal representation data of the plain text. By converting this to ASCCI code, the sender's plaintext can be recalculated.

m' = c k = 68 65 6c 6c 6f

m = "hello"

You can send an encrypted sentence like this. The key k (aa bb cc dd ee) is information shared in advance by both the sending and receiving sides and must have the same length as the plaintext.

A one-time pad is a one-time password. It is a password that is used once and discarded.

One-time pad ciphers, including the Bannum cipher, cannot be deciphered. In other words, even if an eavesdropper eavesdrops on the encrypted message c, he cannot obtain information about the message m.

This is because if the encryption key k is generated completely randomly, c=m=c k is also a completely random message, so information about m cannot be obtained from c.

One-time pad ciphers cannot be decrypted realistically because there are a large number of keys that need to be searched.

Also, if you decrypt for key retrieval, you may eventually find an encryption key that matches the plaintext, but you cannot determine whether the plaintext is real or not. In 1949, it was mathematically proven by Shannon that the one-time pad password was 'secure in information theory'.

Although one-time pads such as Bannum ciphers have the highest security, they are not practical due to the following problems.

The drawbacks of one-time pad ciphers are:

First, there is the issue of key delivery. Common key cryptography uses the same key for encryption and decryption. Therefore, the sender and receiver need to share an encryption key random number sequence k of the same length as the message being sent as a preliminary preparation. For example, if you encrypt and send 100 bits, you must share the random number sequence of the 100-bit encryption key and decryption key in advance.

This is a difficult task. How to share 'k'. This task is the key delivery problem of common key encryption.

Second, reuse of keys is prohibited. In one-time pad cryptography, each time a message is sent, the sender and receiver need a new, different common key random number sequence k. This is because if you continue to use the once shared k, the chances of it being decrypted through ciphertext interpretation increase.

Third, key generation and synchronization. One-time pad encryption requires a new encryption key equal to the length of the plaintext of the message every time the encryption message is changed, but it is not easy to generate a new encryption key. Additionally, the length of the message and the length of the encryption key must be the same. If even one bit is misaligned or different, subsequent decoding becomes impossible.

Fourth, key management. If a new key is needed every time a message is changed, the number of keys increases in proportion to the message, so the cost of generating and managing the key increases. In the case of common key encryption, if there are N senders and receivers, N(N-1)/2 keys are needed. In order to decrypt the ciphertext, the encryption key must be stored and managed. This is because the ciphertext cannot be decrypted if the key is not preserved.

As mentioned above, the one-time pad password is 'secure in information theory', but it is not practical due to operational problems. Therefore, a desirable new encryption technology is an encryption that is 'information theorically safe' and can reduce the above drawbacks, which is also the goal of the present invention.

(b) Stream cipher, block cipher

Common key ciphers include stream ciphers and block ciphers. Stream cipher is a general term for an algorithm that sequentially processes data according to the stream. Stream cipher is a common key cipher that processes in units of 1 bit or several bits. The processing speed is as fast as the Bannum cipher, which calculates the message plaintext and key sequentially by exclusive OR. The size of the secret key can be smaller than the plaintext size, and the encryption key uses a pseudorandom number generated from the secret key. In stream ciphers, the secret key should not be fixed. The secret key becomes the seed of the pseudorandom number generator, and the same pseudorandom number string is generated from the same secret key. Therefore, if the plaintext corresponding to the ciphertext is known, the pseudorandom number sequence is specified, making it dangerous to eavesdrop.

Block cipher is a common key encryption method that divides plaintext into blocks of certain units and encrypts them. This is an algorithm that always produces the same ciphertext when the block is encrypted with a secret key. There are several ways to encrypt every block, and each block is assigned an encryption mode. Representative block ciphers include DES (Data Encrytion Standard) and AES (Advanced Encrytion Standard). DES is an algorithm that encrypts 64-bit plaintext into 64-bit ciphertext using a 36-bit key. AES divides one block into 128 bits and selects key sizes of 128, 192, and 256 bits. AES encryption is initially set according to the selected secret key, and then encryption is performed by repeating a process called ground a certain number of times.

Although the above-mentioned common key encryption has a fast processing speed, the problem of key sharing is difficult. In other words, the sender and receiver must share the same common key, but it is difficult to share the common key in advance.

(c) Sharing of keys

-DH method

The first solution to the key sharing or key delivery problem, which is a difficult problem in common key cryptography, was proposed by Deffie and Hellman and is called the DH law. The outline of the DH Act is as follows.

The sender sends two prime numbers P and G (generator) to the receiver, prepares a random number A, and transmits the calculation result of G ^A mod P to the receiver. The receiver prepares a random number B, calculates G ^B mod P, and sends the result to the sender.

The sender calculates mod P by multiplying the calculation result sent by the receiver by A.

In other words, the key calculated by the sender = (G ^B mod P) ^A mod P, and this value becomes the sender's encryption key.

Meanwhile, the receiver also obtains the mod P value by multiplying the calculation result sent by the sender by B.

The key calculated by the recipient = (G ^A mod P) ^B mod P, and this value becomes the recipient's encryption key.

The calculation result value becomes the same value, resulting in sharing the same key.

-Quantum key delivery

The method of performing the key delivery using the properties of quantum is called quantum key distribution (QKD). QKD encrypts the plaintext with a common key and delivers the common key using QKD.

(2)Public key encryption

Another encryption method that solves the key sharing problem of public-key cryptography is public-key cryptography. Public key encryption, unlike common key encryption, is an encryption method that uses different keys for encryption and decryption. Public key cryptography consists of three algorithms: key generation, encryption, and decryption.

The representative method of public key encryption is RSA encryption, and its outline is as follows. E and N are public keys for encryption, and D and N are private keys for decryption.

Cipher text = (plain text) ^E mod N, N = pxq (p, q are prime numbers), L =lcm(p-1, q-1), gcd(E, L)= 1

plain text = cipher text ^D mod N, E x D mod L =1

The safety of RSA encryption is based on the theory that prime factorization of the product of large prime numbers (2048 bits) cannot be solved within a realistic time, even using current supercomputers.

It is known that the RSA password can be decrypted using Shor's algorithm if a quantum computer with an error correction function is developed. Shore's algorithm is known to be capable of high-speed factorization using a quantum computer using quantum Fourier transform. If prime factorization of 2048 bits is realized using Shore's algorithm, the RSA2048 cipher will be cracked and its effectiveness will disappear.

(3) Hybrid cryptography

The shortcomings of public key cryptography are that it is approximately 1000 to 10000 times slower in processing speed than symmetric cryptography [https://www.cryptopp.com/benchmarks.html], and is known to be vulnerable to man-in-the-moddle attacks. As a result, hybrid encryption was proposed as an alternative. An overview of hybrid ciphers is as follows. The message is first encrypted using high-speed symmetric encryption. When encrypting the message, the encryption key used is encrypted with the public key. Compared to the length of the message, symmetric encryption has a short key and is therefore fast. Hybrid cryptography uses pseudorandom number generator, symmetric cryptography, and public key cryptography techniques simultaneously.

(4) Elliptic curve cryptography

It refers to the overall encryption technology using a mathematical object called an elliptic curve. There are public key cryptography, key sharing, and signatures using elliptic curves. It is widely used because it has high safety due to its short key size.

The algorithm of elliptic curve cryptography is as follows.

Convert the plaintext m to a point on the elliptic curve E, set a random number r, public key pk, private key x, and reference point P, and then calculate c ₁ =rP. Using the public key pk, calculate c ₂ = M +rY(Y=xP) and generate c = ( c ₁ c ₂ ) as ciphertext.

Meanwhile, the decoding algorithm is as follows.

Decrypt the ciphertext into plaintext by calculating M = c ₂ - xc ₁ .

(5)Post quantum cryptography

Cryptography that is difficult to decipher even with a quantum computer is called post-quantum cryptography or quantum-resistant cryptography. Post-quantum cryptography refers to cryptography that is difficult to crack even with a quantum computer, and refers to cryptography that operates on current computers. Depending on the underlying mathematical problem, quantum-resistant cryptography includes lattice-based cryptography, code-based cryptography, multi-variate cryptography, isogeny-based cryptography, There are hash-based digital signatures, etc.

As mentioned above, it can be seen that the key tasks of encryption technology are the type of message plaintext, generation of encryption key, encryption algorithm, and key delivery for key sharing.

The present invention provides an encryption key generation, encryption algorithm, and key delivery system and method that are different from the existing encryption technology.

Figures 1 (a) and (b) illustrate an embodiment of a system and network environment in which the encryption technology of the present invention is implemented.

Figure 1 (a) shows an example of a network including a mobile cloud, and Figure 2b shows an example in which the present invention is utilized in a P2P network environment. However, the encryption method of the present invention is independent of the type of network. For example, any of the Internet, Bluetooth, WIFI, 5G, 6G wireless, quantum networks, etc. can be implemented. Additionally, the device on which the invention's password is executed can be any device that can be connected to a network, such as a smartphone, smart watch, CCTV, sensor device, tablet, or PC.

The present invention provides encryption technology for the plaintext that is the subject of the sender's encryption. As mentioned above, the plain text of the present invention refers to an object of encryption, such as a sender's text file, audio file, video file, or multimedia file combining the above data. The plaintext of the encryption target may include works combined with the NFT, that is, text, photos, graphics, pictures, audio, video, and multimedia files combining the data.

The method of generating the plain text may be any method as long as it can be digitized. For example, works of art manually created by humans, such as paintings and music, or photographs, graphics, audio, and video works created with digital devices, etc., can be digitized. Any object that requires a password can be plaintext, no matter how it was created. In addition, the plaintext is mainly produced, stored, and managed by the sender's and receiver's devices.

The encryption key of the present invention is generated as follows.

In the present invention, encryption key generation is directly related to random number generation.

In cryptography, random numbers are used to generate keys and authenticate messages in symmetric cryptography, and are mainly used to generate key pairs in public key cryptography and digital signatures. Since the key must not be known to eavesdroppers, random numbers are used to prevent the encryption key from being known. The properties of random numbers are classified as follows.

1) Randomness: Random without statistical bias

2) Unpredictability: The next sequence cannot be predicted from the past sequence. 3) Irreproducibility: The same sequence cannot be created. In other words, it is classified as having no choice but to keep the original in order to reproduce it.

How random the random number used to generate the encryption key is has a significant impact on determining the safety of the security system. We need pure random numbers that provide true randomness, not just the appearance of randomness. Currently known random number generators include: Random number generation by hardware includes thermal noise generated from the CPU, keystroke speed, mouse movement, etc., and pseudo-random number generation methods by software include 1) random method 2) linear pool method 3) method using one-way hash box 4) How to use a password 5) ANSI X9.1, etc. Also, through quantum random number generation, there are random numbers generated by extracting from the physical world of pure natural phenomena rather than from humans. Also called completely random number, natural random number, or pure random number. A quantum random number generator is a random number generator that relies on randomness that occurs in quantum mechanical phenomena such as radioactive decay, vibration, and observation of photon polarization.

Unlike the existing random number generation method, the present invention is an encryption technology that uses the sender's or receiver's media content file that is created, stored, and managed on the user's (sender/receiver's) smartphone or other device as a key. The present invention is an encryption technology that uses the sender's or receiver's multimedia content file as an encryption key for the plaintext written in the sender's multimedia.

The encryption key of the multimedia content file of the sender or receiver of the present invention is a key that guarantees security in information theory, and encryption and decryption are performed using this key.

Figure 2 is a photo image created by the sender or receiver stored in the 'album' folder of a smartphone that can be used as a random number generator for generating the encryption key of the present invention. The menu of the album folder consists of video, selfie, live photo, screen shot, etc. Videos, selfie photos, etc. stored in the album of the smartphone include multimedia content files, and these files are stored as binary data, and these binary data are also called bit strings.

A feature of the present invention is that the binary data of the user's media content file can be plaintext to be encrypted and can also be used as a 'key' for encrypting the plaintext.

The data stored in the smartphone of the sender or receiver will be described.

The image of the photo in FIG. 2 is stored in units called pixels. The photographic image is created using a camera. Therefore, the number of pixels in the generated photographic image varies depending on the resolution of the camera. For example, the resolution of the front and rear cameras of the Iphone 13 Pro is 12 million pixels each. This means that when one photo is taken with the above camera, a photo with 12 million pixels can be created. These generated photographic images are displayed on the smartphone's display. For the iPhone 13 Pro, the display resolution is 1170 x 2532 pixels for 6.1 inches, and 1284 x 2778 pixels for 6.7 inches. Photos taken with the smartphone are compressed and displayed on the display.

The photographic images in FIGS. 3 and 4 are in color. In the case of a color image, as shown in FIG. 6, one pixel of photo data is represented by three color data RGB (Red, Green, Blue). Each color data value has a value between 0-255 and represents the degree of the pixel's color Red, Green, and Blue. Each pixel can express 256x256x256 = 16, 777,216 colors by combining 8-bit basic color values. In other words, the color of one pixel is expressed using 24 bits, a combination of three colors. In addition, the color pixel can be expressed as a 32-bit data value per pixel by adding 8 bits of an alpha value indicating the transparency of the pixel. It can also indicate the location (X, Y) of a pixel on the display and can also search by specifying one pixel on the display. Therefore, you can search for the pixel color value of a specific point on the smartphone or find the location of a pixel on the display with a specific color value.

Therefore, for an image of 1024*1024 pixels, storage space takes about 24Mbits. Compression techniques are used to reduce the space required for storage. Popular compression techniques include JPEG (Joint Photographers Encoding Group), GIF (Graphic Interchange Format), and TIFF (Tag Image Format), which are standardized by ISO. Such photographic images can be used as keys in the present invention.

Figure 5 shows a text file that can be used as a random number for an encryption key in the present invention. Character data is expressed in unicode.

Figure 7 shows the creation process of a media content file consisting of audio such as voice and music that can be produced on the user's smartphone. It represents the process of digitizing audio analog data and converting it to binary data.

Audio data has an associated inherited time dependency. Audio is digitized, and the size of digital audio varies depending on the technology used. Digitized audio can be efficiently compressed to reduce storage media specifications.

The binary data of the audio file, which is the user's multimedia content created on the user's smartphone through the above process, can be used as the key of the present invention.

Figure 8 shows the creation of binary data for a multimedia video file in which audio and video are synthesized. This simple program displays the data of a video file, which is multimedia content compressed in MP3 or MP4 format. The video file is expressed as binary data, but because it is long, it is converted to hexadecimal data for convenience. From the binary data file of the video, specific audio and video image data, content of a specific time, and content of the video can be searched and specified.

Digitized video requires large storage space. In order to reduce storage space, it is necessary to apply compression techniques. MPEG (Motion Pictures Encoding Group) is a standard established by ISO for compression and video storage media. Standards MPEG 2, MPEG3, and MPEG4 provide ways to store audio along with compressed video.

The present invention can use the binary data of a video file, which is multimedia content produced on the user's smartphone, as a 'key' as described above.

The key using the binary data of the user's multimedia content file of the present invention has the following basic differences from the key generated by an existing random number generator.

First, the user's media content file as the random number generator of the present invention cannot be reproduced except by copying. This is because media files individually created by the sender or receiver cannot be the same. Each individual cannot produce content made from the same data, even at the same time and in the same space. Even if we assume that the same content is produced at the same time, location, and situation, the bit strings of data for the content produced by each individual cannot be the same. Just as the content produced by each individual can be distinguished by metadata such as producer, production date, location, target, etc., we can also know from experience that reproducible content can never be produced even if it looks the same on the outside. Text, images, etc. that have spatial properties, sounds, videos, or animations that have temporal properties, and multimedia data that is integrated and composed of these media data have complex spatial and temporal relationships depending on the characteristics of each component media. For example, even if you take a photo of the same subject, the same photo cannot be reproduced. Also, even if it is the same text message, the same person cannot produce the same content at the same time. It is also impossible for a third party to predict the multimedia content files produced by each sender or receiver. Furthermore, it is impossible to predict which media file was used as the encryption key for the plaintext of the media, and even if the encryption key is known, it is impossible to determine which media file was used for which plaintext. Using the multimedia content file of the present invention as described above as a random number generator satisfies the first condition of 'information security' of encryption described in the One Time Pad, that is, the basic requirement that the random number, which is the seed of the encryption key, be unreproducible. .

Second, the multimedia content file as a random number generator for generating an encryption key of the present invention has a data structure in the same format as the plaintext that is the sender's encryption target, so it is possible to selectively use various plaintexts and various keys in an optimal combination. In other words, user plain text varies depending on the type of expression media and its size also varies. The encryption key of the method of the present invention can flexibly respond to various requests for such plaintext.

As described above, the media content file as a random number generator for generating an encryption key of the present invention satisfies the information theoretic security requirement of encryption, which requires providing a key of the same length or more according to various lengths of the plaintext.

For example, existing true random number generators or pseudorandom number generators cannot respond flexibly to adjusting the length of the encryption key because they only produce output data of the same configuration. On the other hand, the media content file created by the user of the present invention may consist of several K bytes to tens of M bytes. For example, assuming that 1 line of text is 80 bytes and 1 page is 20 lines, one page is 1,600 bytes, or approximately 1.6KB. In the case of an image, a resolution of 620 * 560, a pixel size, and a frame with 24 bytes per pixel can be configured as 1MB. Therefore, a full motion video that requires 30 frames per second has a length of 50GB per 30 minutes. In the case of audio, 64KB of CD quality (44.1 KHz, 16-bit sampling) stereo is 1.4MB per second. . Therefore, if you save a 20-minute speech in voice-level sound quality, it will be about 9.2MB in length, and if you save a 5-minute classical piece in CD quality, it will be about 52MB in size. . Therefore, large-sized multimedia data has the advantage of being able to generate an encryption key that can flexibly respond to the length of the plaintext of various messages.

Third, the multimedia content file as a random number generator for generating an encryption key of the present invention can flexibly provide a one-time pad, which is a condition for the information theoretic security of an encryption key, that is, a key generation interface that can be used once and discarded without reusing the key.

Fourth, the multimedia content file as a random number generator for generating an encryption key of the present invention facilitates the processing and editing of information according to standard specifications in the digitization of multimedia data, making it easy to standardize the generation of keys and application of algorithms.

Fifth, the multimedia content file as a random number generator for generating an encryption key of the present invention enables interactive manipulation of the plaintext subject of encryption and the encryption key, thereby providing a more user-friendly and easy-to-use encryption system.

Sixth, the multimedia content file as a random number generator for generating encryption keys of the present invention is capable of compressing/restoring large amounts of information, preventing deterioration of information due to transmission or output, and is easy to use packet communication technology and allows information sharing through transmission and reception. easy

Seventh, the multimedia content file as a random number generator for generating an encryption key according to the present invention is safely stored in the file system or database of the sender or receiver device and can effectively respond to key information search, etc.

Eighth, the encryption algorithm using the key of the multimedia content file of the present invention enables encryption and decryption by exclusive OR calculation, like the one-time pad encryption of the common key encryption method, and has a fast processing speed.

Ninth, the generation of an encryption key using a multimedia content file of the present invention can use existing multimedia processing software and hardware as is, making it possible to provide an economical encryption system and method.

As described above, the technical feature of the present invention is that the encryption/decryption key is executed as a media content file.

As mentioned above, solving the key delivery problem in common key cryptography is the biggest challenge. The key delivery methods known so far in the common key cryptography include the DH method, public key method, high-brit method, elliptic curve method, post-quantum cryptography method, and quantum key delivery method, as described above.

The encryption method of the present invention can provide various methods for generating the encryption key and delivering the key.

In the present invention, the prerequisites for the technical configuration that must be provided between the sender and receiver of messages are explained. The sender and receiver always disclose the public key, and the public key method disclosed by the sender and receiver devices is a program and procedure that can provide known encryption methods such as RSA, elliptic curve, ElGamal, lattice, and quantum ( Assume that a protocol is in place.

In the present invention, the private key of the receiver or sender can be encrypted according to the public key method provided by the receiver or sender. That is, it is assumed that regardless of the encryption method of the public key provided by the receiver or sender, the private key of the receiver or sender can be encrypted or decrypted in a manner corresponding to the public key encryption of the receiver or sender. Decryption of the recipient's private key using another public key can also be processed according to the existing encryption/decryption formula.

Figure 9 shows a first embodiment of the present invention.

If the sender 91 wishes to encrypt and transmit his/her plaintext, the ciphertext of the plaintext to be transmitted must be created before transmission. The sender can write (90) the sender's plain text using his or her own device, for example, the keypad, microphone, camera, etc. of a smartphone, and store it in his or her own device.

The sender creates a plaintext file subject to encryption (92) and loads it into the main memory of the sender device.

The sender must select (93) a media content file for generating an encryption key that is stored and managed in the device used by the sender as the encryption key for encrypting the own plain text. The media content file for generating the selected and designated encryption key may be one of a text file, a photo, a graphic, an image file, an audio file, a video file, or a mixture of these media.

In order to encrypt the plaintext, the sender loads the sender's plaintext encryption key file into the main memory and then displays it on the screen of the device (94). The sender's plain text encryption key file refers to a media content file stored in the sender's device, and one of the stored media content files of the sender is selected and displayed on the screen of the sender's device (94).

Next, the sender touches and designates an encryption start point on the displayed encryption key file (95). The information on the point touched by the sender is character or numerical data with the location, time, and characteristic meaning of the point touched by the sender, or a specific bit, byte, or word among binary data constituting the sender's media content file. It may be unit data.

3, 4, and 5 are examples of text files displayed on the sender's smartphone and photo, audio, or video files of media content for generating an encryption key, and the sender enters the secret key on the photo image file displayed on the sender's device. This is an example of a screen where the sender selects the starting point of the 'key' by touching for the creation of .

For example, in the case of the photographic images of FIGS. 3 and 4, this refers to the binary data of the center point pixel of the point touched by the sender, that is, the position (X, Y) value of the pixel of the touch point.

In a text data file as shown in FIG. 5, touch point information refers to the position of a character or Unicode at a point designated by the sender by touch on the displayed text file for generating an encryption key. In addition, as shown in Figures 7 and 8, if the multimedia content for generating an encryption key displayed on the sender's device is an audio or video file, the location coordinates of the point touched by the sender in the audio or video file for generating the encryption key and the specific pixel Information value, the time from the display start point to the point of touch, for example, may be a specific time such as 1 minute and 30 seconds from the display start time, and may be specific character information or content information or meta of a specific audio video that can be searched at the touch point of the file It could be data.

As shown in FIGS. 3 and 4, information on the starting point designated and selected by the sender on the photo image file displayed (94) on the sender's device is stored in the memory of the sender's device. For example, the coordinate values (X, Y) of the starting point on the media file are stored in the memory of the sender device. The coordinate values (X, Y) of the sender's stored starting point are used as a secret key 96 for the sender's encryption.

The sender synchronizes the bit string of the loaded plaintext file 95 with the bit string of the encryption key file 98 set to the encryption start point designated by the sender, calculates exclusive OR, and stores the result in a file. The newly created file is the ciphertext (encryption file) 912 of the sender's plaintext.

In the present invention, when encrypting the sender's plaintext is to be performed, the encryption of the sender's plaintext is created by calculating the bit string of the sender's plaintext and the bit string of the media content file, which is the sender's encryption key, by exclusive OR (XOR).

That is, sender ciphertext = bit string of sender plaintext bit string of sender cipher key

In Figure 10, the first embodiment of the present invention described above will be described in more detail.

Assume that the sender's plaintext to be encrypted is composed of bit strings such as 1011.........1100......1010 (plaintext bit string). Since the bit string representation of plain text data as described above can digitize any media such as text, photos, graphic images, audio, and video, the above embodiment can be used to explain the general embodiment of the present invention.

The sender encrypts the sender's plaintext with the sender's encryption key file. The data bit string configuration of the sender's encryption key file is 1110...............0010 (touch point coordinates 123, 456).............1001 (the bits of the sender's encryption key). 10). If the encryption start points of the plain text and the encrypted file are each pixel coordinate (0, 0), calculating the bit string of the plain text and the bit string of the sender encryption key file by exclusive OR is 1001........ It becomes .0101............0100 (sender's ciphertext).

However, if the bit string position of the plaintext is set to (0, 0) and the start point of the sender's encryption key is selected as pixel coordinates (234, 123)… ..1001… Since it is shifted like 1110, if the bit string from the start pixel of the sender's plaintext and the bit string of the RGB value of the pixel at the coordinates corresponding to the receiver's secret key are calculated by exclusive OR, the result is 1001... .0101… It becomes 0100. The reason is that at the beginning of the sender's encryption file, (123 456) of the sender's encryption key file becomes the initial value (0, 0) for shift calculation, so the calculated value is 1001... .0101… It becomes 0100. The calculated value becomes the ciphertext of the sender's plaintext.

Additionally, the sender encrypts the sender's secret key (96) (913). That is, when the sender encrypts his plain text, he encrypts the starting point information of the encryption key file used with the public key provided by the receiver. If the sender's encryption key file is the photo image of Figure 3, the pixel coordinate value of the start point is (123,456), so the plaintext ciphertext, plaintext encryption key file, and secret key created by the sender of the pixel are the sender's secret key. It is stored in the device and transmitted to the recipient's device upon receiving the sender's transmission request.

The recipient's device includes a smart phone, tablet, PC, cloud server, or terminal device on a P2P network.

The encryption method 913 of the sender's private key can use an existing public key encryption method.

For example, if the pixel location of the point selected by the sender on the media content file corresponding to the sender's secret key is (123, 456), this coordinate value is encrypted as the secret key. The encryption method of the coordinate value is explained using RSA and elliptic curve encryption as follows. Assuming that the public key of the recipient's RSA encryption is (E, N) = (5, 323) and the private key (D, N) = (29, 323), the coordinate value (123, 456), which is the sender's private key, is The ciphertext is the ciphertext of the secret key = 123 ⁵ mod 323 = 225, 456 ⁵ mod 323 = 114.

In another embodiment, the sender's secret key coordinates (123, 345) are plaintext, and the receiver's password is the reference point P on the elliptic curve E: y ² = x ³ + x + 6 mod 11 (2, 7) Assume an elliptic curve encryption method with private key x = 7 and public key Y = xP. Also, assume that the result of converting the plain text into one coordinate on the elliptic curve is M = (10, 9). The recipient's public key becomes Y =xP=7(2, 7) =(7, 2) according to the formula. Also, according to the formula of elliptic curve cryptography, the ciphertext c ₁ =rP (assuming the generated random number is 3) =3(2, 7) = (8, 3) and c ₂ = M + rY = (10, 9) +3 (7, 2) = (10, 2), and if the sender's plaintext is encrypted with the sender's elliptic curve, the ciphertext c = (c ₁ , c ₂ ) becomes (8.3), (10, 2). .

Since other embodiments of the encryption method 913 for the secret key of the present invention are well-known techniques, description thereof will be omitted.

The receiver, having received the sender's plaintext encryption file, plaintext encryption key file, and secret key encryption file, decrypts the encryption file of the sender's private key. The decryption process of the sender's private key is performed using the recipient's private key according to a public key method provided by the recipient as a public key in advance. For example, according to a public key encryption method, the recipient It depends on the public key encryption method provided to you.

For example, it can be decrypted using a known method determined according to RSA, elliptic curve, post quantum cryptography, quantum key delivery (QKD), etc.

Using the decrypted secret key information of the sender, an encryption start point is specified in the sender's encryption key file, and a bit string of the sender's encryption key file with the specific start point as the encryption start point and a bit of the sender's plaintext ciphertext are used. Columns are calculated using exclusive OR. That is, the bit string of the plaintext ciphertext 912 and the bit string of the plaintext encryption encryption key file 914 are calculated by exclusive OR to obtain the plaintext 915.

Sender plaintext = Sender’s plaintext encryption file Sender’s plaintext encryption key file

The above equation will be described in detail. As in the embodiment of FIG. 10 above, decoding the sender's plaintext uses a bit string of the sender's plaintext ciphertext 1101.....0101......0100 (sender's plaintext ciphertext) and a bit string of the sender's encryption key file. It is achieved by calculating 0110........1001.......1110 by exclusive OR. As a result of the above calculation, the sender's plaintext 1011......1100......1010 (sender's plaintext bit string) is accurately obtained.

Figure 11 is a flowchart explaining the second embodiment of the present invention.

The receiver in FIG. 11 is a communication user who receives encrypted text from an unspecified number of senders. In order to receive encrypted text from an unspecified number of senders, the receiver creates and discloses the sender's plaintext 'encryption key file' on its own.

At this time, the receiver's private key is simultaneously generated and encrypted with the sender's public key, and then the ciphertext of the receiver's private key and the sender's plaintext encryption key file are publicly transmitted to the senders.

In the second embodiment of the present invention, the method of generating the recipient's encryption key is as follows.

First, the receiver receives a public key from the sender.

The recipient 110 generates an encryption key on the recipient's device for encryption of the sender's plain text in a communication environment with an unspecified number of or one-to-one senders and delivers it to the senders using his or her smartphone. One of the recipient's media content files is loaded into the main memory of the recipient device from the device's file folder or database to generate the sender's encryption key (111). At the same time, the media content file for generating the encryption key selected by the recipient is displayed on the recipient's device (112).

The recipient specifies the starting point of the encryption key, which indicates the generation point of the encryption key, on the media content file displayed on the recipient's display by touching (113). Information on the encryption key start point designated by the recipient becomes the recipient's secret key 114. The touch can be performed automatically by the system or manually by the recipient.

The technical significance of the media content file for the sender's declarative encryption key and the receiver's secret key is the same as the description in the first embodiment.

The receiver transmits the sender's plaintext encryption encryption key file 115 generated by the receiver as described above to the sender 116. At this time, the receiver's private key is encrypted with the public key provided by the sender and transmitted at the same time.

The sender, who has received the encryption key file for plain text encryption of the sender sent by the receiver, decrypts the encrypted text of the private key sent by the receiver with the sender's private key and decrypts the encryption key file sent by the receiver according to the information of the receiver's private key. Specifies the encryption start point in the encryption key file for the sender's plaintext encryption. Then, the bit string from the pixel position of the specific encryption start point and the bit string of the sender's plain text are calculated by exclusive OR (117). The calculation result becomes the ciphertext 118 of the sender's plaintext. The sender transmits the ciphertext of the encrypted plaintext as described above to the receiver (119). The receiver who receives the ciphertext decrypts the sender's ciphertext into plaintext using the receiver's encryption key and secret key information. That is, the sender's plaintext (1111) can be obtained by calculating (1110) exclusive OR of the bit string at the position indicated by the secret key information in the received ciphertext file and the receiver's cipherkey.

Sender plaintext = Sender plaintext ciphertext file Receiver plaintext encryption key file

In the first and second embodiments of the present invention, the message sender or receiver generates a plain text encryption key file and a secret key, respectively, and publicly or secretly transmits the plain text encryption key file and secret key to the receiver or sender, and the receiver Alternatively, the sender directly uses the received plaintext encryption key file and secret key of the sender or receiver to generate ciphertext/decrypted plaintext.

In the case of the first and second embodiments of the present invention, the common key delivery is a plaintext encryption key provided to the sender or receiver and is shared publicly.

Figure 12 shows a third embodiment of the present invention.

The third embodiment of the present invention can provide stronger encryption than the first and second embodiments by providing separate encryption key generation and encryption key delivery keys.

The encryption process of the third embodiment of the present invention is as follows.

That is, in the third embodiment of the present invention, when the sender uses the sender's plaintext encryption key as his or her media content file, the sender transmits only the plaintext ciphertext and the secret key encryption file to the receiver, and then sends the sender's plaintext encryption key to the receiver. The file transmits the sender's plain text encryption key file to the recipient using a public key file for common key delivery provided by the recipient. As a result, common key sharing is possible between the sender and receiver.

As shown in FIG. 12, the recipient 120, who has received the sender's plaintext ciphertext and secret key ciphertext, receives the sender's encryption key that generated the sender's plaintext ciphertext by using the A media content file is selected (121), loaded into main memory, and displayed on the screen of the device (122). The recipient designates the password start point by touching the displayed media content file (123). The information on the touch-designated file may be various types of information, such as the recipient's secret key 124, as described above.

The media content file selected by the recipient is a public key for receiving the sender's plaintext encryption key (public key for plaintext encryption key delivery), and the start point information on the touch-designated media file becomes the recipient's secret key.

The recipient's media content file is transmitted to the sender 127 along with the recipient's private key encrypted text 126 as a public key file 125 for receiving the sender's encryption key. The receiver's private key encrypted text 126 uses a public key encryption method known to the sender as described above. For example, if the recipient's private key information is pixel location information in the file, known public key encryption methods such as RSA and elliptic curve can be used as described above.

The sender 127, having received the recipient's public encryption key 115 and the encrypted text 126 of the private key, decrypts the encrypted text of the recipient's private key and obtains private key information.

The procedure for decrypting the encrypted text of the recipient's private key follows the decryption algorithm of a known encryption method as described above.

The sender encrypts the sender's plaintext encryption key using the receiver's private key obtained through decryption and the common key delivery public key file 128 sent by the receiver. The encryption sequence is as follows.

First, the sender calculates and specifies an encryption start point on the recipient's common key delivery public key file 128 using the decrypted information of the recipient's private key. For example, as described in the above embodiment, if the start point information is the coordinate value of a specific pixel in the public key file for common key delivery, the coordinate value is set as the pixel of the encryption start point. The set pixel is used as an encryption start point, and the bit string of the reset recipient's common key delivery public key file 128 and the bit string of the sender's encryption key file 129 are calculated by exclusive OR.

The file generated as a result of exclusive OR calculation as described above becomes the ciphertext 1210 of the sender's plaintext encryption key.

That is, the ciphertext file of the sender's plaintext encryption key = the file of the sender's plaintext encryption key. The plaintext encryption key file for recipient common key delivery.

The generated encrypted text of the sender's plaintext encryption key is transmitted back to the recipient device 1211.

The above procedure is the common key delivery method of the present invention. That is, the sender's plaintext encryption key is generated as encrypted text using the recipient's public encryption key and secret key sent by the receiver to the sender, and the generated encrypted text of the sender's plaintext encryption key is transmitted back to the receiver.

The receiver, who has received the ciphertext of the sender's plaintext encryption key, decrypts the ciphertext of the sender's encryption key. The decoding process is as follows.

The receiver calculates the bit string 1212 of the received ciphertext file of the sender's encryption key and the bit string of the public key file for common key delivery of the receiver by exclusive OR, and calculates the sender's plaintext encryption from the sender's encryption key ciphertext file. The key file can be decrypted (1213).

Sender's encryption key = Sender's encryption key ciphertext file Recipient's common key Public key file for delivery

Since the receiver has already provided the location of the decryption start point in the sender's ciphertext file, processing is possible easily.

Additionally, the receiver can decrypt the sender's original plaintext 1213 using the sender's plaintext encryption key file decrypted through the above calculation using the following calculation procedure. That is, the receiver synchronizes the obtained bit string from the starting point of the sender's plaintext ciphertext file with the bit string from the starting point of the sender's plaintext encryption key file and calculates it by exclusive OR.

That is, sender's plaintext = sender's plaintext encryption key file sender's plaintext ciphertext

The above process will be explained in detail using the above example.

In the embodiment of using the above photo image file, a portion of the bit string of the recipient's common key delivery public key file is 1110............1101(789, 987). ....................0001 (recipient public key).

That is, the location of the encryption start pixel in the recipient's plaintext encryption key file is (789, 987), and a part of the RGB value of the pixel at this location is '1101'.

The bit string of the sender's ciphertext is 0011............0011......................0110. Therefore, the sender's plaintext encryption key can be obtained by calculating the bit string of the receiver's common key delivery public key file and the bit string of the sender's ciphertext by exclusive OR. That is, 0011............0011............................0110 (ciphertext file of sender's encryption key) 1101............... 0001............................1110 (recipient public key) = 1110............0010............................ It becomes 1000 (sender encryption key).

The above calculation result means that the sender's plaintext encryption key was delivered with the receiver's common key delivery public key and the common key was shared.

As described above, since the sender's encryption key has been decrypted in the receiver's device, the receiver can decrypt the sender's plaintext from the sender's plaintext ciphertext sent by the sender using the decrypted sender's encryption key file.

In other words, decryption (1213) of the sender's plaintext is possible with the following calculation.

The above equation will be described in detail. As in the above embodiment, the decryption of the sender's plaintext is performed using the bit string of the sender's plaintext ciphertext 0100...1110......0011 (the sender's plaintext ciphertext) and the bit string 1110 of the sender's encryption key file. ......0010.......1000 is calculated as exclusive OR. As a result of the above calculation, the sender's plaintext 1010......1100......1011 (sender's plaintext bit string) is accurately obtained.

As described above, the present invention can decrypt the sender's encrypted text by receiving the sender's encryption key through the receiver's common key delivery public key.

The third embodiment of the present invention can be modified as follows. This is referred to as the fourth embodiment of the present invention.

That is, before the sender sends the ciphertext of the sender's plaintext, the sender first transmits the sender's plaintext encryption key and secret key ciphertext to the receiver, and then the sender sends the ciphertext of the plaintext and the ciphertext of the encryption key to the recipient who received the ciphertext of the plaintext in advance. Common key is generated using the public key and private key for delivery. And the sender's plaintext ciphertext, the sender's secret key ciphertext, and the sender's ciphertext ciphertext are simultaneously transmitted to the recipient device.

The difference between the third embodiment of the present invention and the fourth embodiment is that the timing of transmitting the receiver's public key and private key for common key delivery to the sender is different, and the algorithm accompanying the encryption system and method of the present invention is It's the same thing.

That is, the third embodiment is a method in which the receiver transmits the public key and private key ciphertext for common key delivery to the sender after the receiver receives the ciphertext of the sender's plaintext, and the fourth embodiment of the modification is This is a method of receiving the recipient's common key key delivery public key and private key ciphertext from the recipient in advance before transmitting the ciphertext of the plaintext to the recipient. This difference is whether the delivery of the common key is performed simultaneously with the sender's ciphertext or whether the sender's ciphertext is first transmitted to the receiver and then the receiver's public key and private key ciphertext for delivery of the common key are received from the receiver. This is only a matter related to the delivery time of the common key, and there is no difference in the meaning and effect of the encryption technology of the present invention.

Figure 13 is a processing flowchart of the fifth embodiment of the present invention.

In the fifth embodiment of the present invention, the following procedures are added to the configuration of the third and fourth embodiments of the present invention. When the generated plaintext ciphertext of the sender 120 is transmitted to the recipient's device (121), the receiver 122 converts the received plaintext ciphertext of the sender into media content corresponding to the recipient's common key delivery public key. A file is selected, and a new file is created by calculating the exclusive OR of the bit string of the sender's plaintext ciphertext and the bit string of the recipient's public encryption key file (123).

That is, the sender's plaintext ciphertext and the receiver's common key delivery public key file = a combined file of the sender's plaintext ciphertext and the receiver's common key delivery public key of the same length.

This is an embodiment in which the above procedure is added. By adding the above procedure, unlike the third and fourth embodiments, the recipient's common key delivery public key 123, which has the same length as the sender's plaintext or ciphertext, can be calculated in advance and provided to the sender. .

The reason is that in the above-mentioned problem of the present invention, the condition that the length of the plain text and the length of the encryption key are the same, that is, the key condition is satisfied. That is, in order to encrypt the sender's plaintext, a file with an encryption key at least equal to or longer than the length of the plaintext is required.

The plain text encryption in the present invention is provided on the premise of an encryption key file having the same length or more. For the received encrypted text of the sender, select a media content file that is the public key for delivery of the receiver's common key, calculate it by exclusive OR, and obtain a public key for delivery of the receiver's common key that is equal to or longer than the length of the sender's encryption key. You can find it.

If the combined file of the receiver's common key delivery public key of the same length as the sender's ciphertext generated by the above procedure is calculated by exclusive ORing the bit string of the sender's ciphertext, the receiver's common key equal to the length of the sender's ciphertext is calculated by exclusive OR. You can obtain the public key for key delivery (124). That is, a combined file of the sender's ciphertext and the recipient's common key and delivery public key of the same length. Sender's ciphertext = Receiver's common key and delivery public key.

The calculation can be performed on the recipient device or by transmitting a combined file of the recipient public key of the same length as the sender ciphertext to the sender device 125. This is because the ciphertext of the sender's plaintext is already stored in the recipient's device or the sender's device. In the latter case, a combined file of the sender's ciphertext and the receiver's common key delivery public key of the same length is transmitted to the sender. The sender performs, on the sender's device, an exclusive OR calculation (126) of the bit string of the combined file of the receiver's common key delivery public key of the same length as the received sender's ciphertext and the bit string of the sender's plaintext ciphertext. Calculation As a result, obtain the public key for delivery of the receiver's common key generated with the length of the sender's encryption key.

The public key file for delivery of the recipient's common key, which is created as described above, is created with the length of the sender's encryption key and is subjected to an exclusive OR calculation (127) with the sender's plaintext encryption key on the sender's device to create a new file. The newly created file is transmitted to the recipient's device by the sender. The newly created file transmitted to the recipient device becomes an encryption file 128 that delivers the sender's plaintext encryption key.

The receiver 129, which has received the encryption file delivering the sender's plain text encryption key, performs an exclusive OR of the bit string of the file delivering the sender's plain text encryption key and the bit string of the public key file for delivering the receiver's common key. By calculating, the encryption key of the sender's plaintext can be obtained (1210). in other words

A file that delivers the sender's plaintext encryption key. A public key file that delivers the receiver's common key. = A file that delivers the sender's plaintext encryption key.

Again, the receiver calculates the bit string of the received plaintext ciphertext of the sender and the bit string of the sender's plaintext encryption key file by exclusive OR to obtain the sender's plaintext (1211).

Sender plaintext ciphertext Sender plaintext ciphertext key file = Sender plaintext

The process of the present invention as described above can provide a flexible encryption system and method based on common key encryption and using various common key delivery procedures.

The following describes a sixth embodiment of the encryption system and method of the present invention.

The password of the present invention can also be used in online call mode.

That is, the sender or receiver can make an audio or video call using a smart phone, etc. The encryption system and method of the present invention can be installed and used in the call mode. That is, the sender or receiver selects the call mode, and before starting the call, the sender or receiver transmits a public key to the other party, and at the same time requests and exchanges the other party's plaintext encryption key file and secret key.

The request may be made only with the public key transmission signal. The sender or receiver who has received the transmission or request generates the plaintext encryption key file and the encrypted text of the secret key on their device and transmits them to each communication counterpart's device for exchange. The procedure for generating the sender's or receiver's plaintext encryption key file or secret key encrypted text is the same as that of the first, second, third and fourth embodiments of the present invention. The sender or receiver who receives the public key of the communication counterpart or requests the plain text encryption key and secret key exchanges their plain text encryption key file and the encrypted text of the private key with the sender or receiver. The sender or receiver, who has received the plaintext encryption key file and the secret key encrypted text, decrypts the encrypted text of the private key, sets an encryption start point on the plaintext encryption key file, and waits to receive a call from the communication partner. Upon confirming that the other party to the call is in a waiting state, the other party touches the encryption start point of his or her plain text encryption key file and then starts the call. An exclusive OR calculation is started between the bit string of the call data and the bit string of the plaintext encryption key file, and the calculation result is transmitted to the communication counterpart via a call line. The sender or receiver, who mutually receives the bit string of the call ciphertext file transmitted through the call line, decrypts the other party's call ciphertext using the public ciphertext file and secret key data on their own device. The ciphertext generation or decryption process using the plaintext encryption key, secret key, and plaintext encryption key file is the same as the above-described description. Therefore, detailed explanation is omitted.

The following is the seventh embodiment of the present invention.

That is, the sender or receiver selects the call mode, and before starting the call, the sender or receiver transmits the public key of the sender or receiver, the plaintext encryption key file, and the encrypted text of the private key to the other party. The sender or receiver who has received the known public key, the public plaintext encryption key file, and the encrypted text of the private key decrypts the encrypted text of the private key on his/her device, sets the encryption start point of the public plaintext encryption key file, and makes a call. The reception status completion is sent to each caller's device and exchanged. Through the above procedure, the sender or receiver can make an encrypted call.

The procedure for generating the plaintext encryption key or the secret key encryption text is the same as that of the first, second, third, and fourth embodiments of the present invention. Upon confirming that the other party to the call is in a waiting state, the other party touches the encryption start point of his or her public plaintext encryption key file and then starts the call. The bit string of the call data of the calling party and the bit string of the public plaintext encryption key file are calculated by exclusive OR, and the result is transmitted to the communication counterpart via the call line. The sender or receiver, who mutually receives the bit string of the call ciphertext file transmitted through the call line, decrypts the other party's call ciphertext using the plaintext ciphertext file and secret key data on their own device. The ciphertext generation or decryption process using the plaintext encryption key, secret key, and plaintext encryption key file is the same as the technical content of the embodiment of the present invention described above. Therefore, detailed explanation is omitted. The call line refers to a device where a call device is connected to a wired or wireless network. Additionally, call data refers to data generated through conversations between the other party on the call.

In general, the amount of data generated from a 10-minute mobile phone call is known to be 1.2 million bytes. The encryption key file of the present invention makes it possible to encrypt the entire 10 minutes of call data using the photo data file of FIG. 3 or FIG. 4.

As with the above embodiments of the present invention, it can be seen that the common key encryption method and key delivery method for key sharing of the present invention are different from the existing encryption method.

The embodiment of the present invention uses an encryption key file for plaintext encryption created by the sender or receiver, and the encryption key file is disclosed to the communication partner. Therefore, the encryption key file is disclosed to eavesdroppers as is. Nevertheless, as explained below, the encryption of the present invention is information-theoretically secure.

The advantages of the encryption system and method of the present invention are as follows.

First, the encryption of the present invention is information-theoretically secure.

Information theoretic safety and computational security are widely known for evaluating the safety of cryptographic keys.

The above information-theoretic security means unconditionally secure and theoretically unbreakable, and was mathematically proven by C.E Shannon in 1949 while evaluating the safety of one-time pad encryption, and is currently It is an established theory.

Shannon's mathematical theory of information theoretic safety is as follows.

Here, M, K, and C are called random variables of the plaintext, key, and ciphertext, respectively. At this time, when the following equation holds for any ciphertext c and any plaintext m, the cipher is said to satisfy information theoretic safety (complete safety, unconditional integrity).

Pr(M = m | C =c) =Pr(M= m)

The meaning of the above equation means that if the “probability distribution of M after the eavesdropper eavesdrops on the ciphertext” does not change from the probability distribution of the original M, then no information has been leaked from the ciphertext.

When interpreted by contrasting the above equation with the encryption method of the present invention, the sender's plaintext m of the present invention is selected by the sender according to probability.

In addition, the key k of the present invention is used by randomly selecting an encryption start point from any media content file of the sender or receiver. As mentioned above, the plaintext and key selection of the present invention are completely independent of each other and have no relationship whatsoever. In other words, the ciphertext of the present invention is simply determined automatically from the plaintext and key.

For example, if the 'key' of the present invention is a photo image as shown in Figure 3 among the media content files, the photo image composed of the pixel information is a one-time 'true random number generator', and the coordinates of one pixel on the photo image are a one-time use. Since it corresponds to a secret key, even if the ciphertext according to the present invention is intercepted, the photo image is one of many photos held by the sender or receiver, and the pixel in the photo is the 6.1-inch display of the iPhone 13, 1170x 2532 = 2,862,440 It's just one of them. Therefore, the probability of the secret key is 1/ 2,862,440. Also, the probability of which pixel will be selected among them is equal to 1/2,862,440 for all pixels. Therefore, the probability of plaintext is equally 1/2,862,440. 'In conclusion, the encryption of the present invention has information theoretic security defined by Shannon above.

There is another interpretation of information-theoretic safety. The key of the present invention is randomly selected from the media content file of the sender or receiver and has no prior or post-conditions. Additionally, touch points selected on the media content file are also random. For example, since the touch pixel in the photo image file in the above figure is one of 2,862,440 pixels, the touch point, which is the secret key, can be found someday by performing pattern matching on all pixels using a brute-force attack. You can. In other words, the brute-force attack is a method of executing decryption using all keys in order and then determining whether the obtained plaintext is correct. However, the total number of plaintexts decrypted in the process is as many as the number of pixels, including the sender's secret key. Therefore, the key of the present invention cannot determine whether the plaintext obtained as a result of sequentially decoding all pixels as a key is the original correct plaintext. Cryptography with these cryptographic characteristics is called information theoretic security.

Second, the key of the present invention is basically a one-time one-time pad. The key of the present invention, like the one-time pad above, satisfies the conditions of an encryption with information theoretic security, that is, the one-time use condition of the encryption key. The 'key' in the present invention uses two types: a media content file of the sender or receiver and a secret key that specifies the starting point of encryption on the file.

Although the present invention is in the category of common key encryption, there is little burden in generating and managing the key. As mentioned above, another disadvantage of the common key encryption is that key management becomes more difficult as the number of communication partners increases.

In general, in the case of the common key encryption, when the number of communication participants is N, the number of keys N(N-1)/2 is required. For example, in the case of common key encryption, if there are 10 communication participants, 10(10-1)/2 = 45 keys are needed. In the case of common key encryption, the number of keys increases as the number of communication users increases, making it difficult to create and manage keys.

In the case of the present invention, although it is an encryption of the same category as a common key encryption, there is less burden in generating and managing the key. That is, since the key generation of the present invention is based on the media content file of the recipient or sender and the touch point information on the content file, the number of key generation can be adjusted using the characteristics of the data of the media content file, and the number of keys can be synthesized. Management is also easy. For example, when using a photo image as shown in Figure 3 above as an encryption key, 2,862,440 secret keys can be generated from one photo image file. That is, in the present invention, a one-time key refers to one media file or one touch point pixel on the media file. Therefore, if one content file is selected as the encryption key, for the 6.1-inch display of the iPhone 13, the number of pixels is 1170x2532 = 2,862,440, so in practice, for the security of the key, from about 10,000 to one secret key can be generated and used without duplication. On top of that, the media content files are divided by week, date, time, communication partner, plain text media, etc., and a plurality of files are created, and a small number of secret keys are assigned to the files and used alternately to make the keys meaningful. It is manageable. As a result, the encryption key of the present invention can implement the encryption system and method by generating less than 2N keys, as in the case of a public key.

The encrypted communication of the present invention may be 1 to N or 1 to 1 for the sender to the receiver. In a 1-to-N communication environment, the receiver can simultaneously disclose the public key and private key of the same receiver to N senders. In addition, if one-to-one individual communication is performed, the public and private keys of different recipients can be publicly provided individually. In the communication environment of the embodiment of the present invention as described above, the 'number of keys' for creation and management of the sender or receiver varies. A password that can meet such technical requirements is the password of the present invention. The technical significance of the technical configuration of the present invention can be said to be a feature that fundamentally differs from the existing encryption method.

The evaluation of the computational security of the present invention's encryption is as follows. Media content files used in the encryption of the present invention may be text files, photo image files, audio files, video files, or a mixture of these media. In the present invention, the things that the eavesdropper can eavesdrop on include the sender's plaintext ciphertext, the sender's encryption key ciphertext file, the recipient's public plaintext encryption key file, and the sender's or receiver's public key file. In the files that can be eavesdropped, an eavesdropper cannot know which media file was used in the eavesdropped file except for the plaintext encryption key file that is public to the recipient. Only the file bit string is visible, and the information structure of the bit string is different depending on the media. In other words, the standard format for each is different: character code for a text file, RGB data for a color photo image, audio compressed data for an audio file, and video compressed data for a video. For the above reasons, it is a computationally difficult problem to determine the file format of the media using only the bit string of the eavesdroppable file.

Meanwhile, it is known that the encryption processing time of the common key encryption key delivery method of the present invention is about 1,000 to 10,000 times faster than other existing methods. In addition, in the key delivery method of the present invention, the encryption of the starting point private key of the encryption key file using the public key method is simple and is much simpler than the key sharing method using the existing public key method.

As described above, the 'key' used for the media content file of the present invention is longer than any existing encryption key. Nevertheless, encryption processing is fast.

In particular, the technical significance of using the multimedia content file of the present invention as an encryption key lies in the fact that it is an encryption based on the information theoretic security of the one-time pad encryption and also has the safety of the amount of computation. The key of the present invention is a one-time password that is used once and discarded, and is easy to use and easy to generate. .

In addition to the above effects of the present invention, it is further summarized as follows.

First, the encryption of the present invention is secure in information theoretic terms. Unlike existing random number generators and pseudo-random number generators, the seed for generating the encryption key of the present invention uses the multimedia content files of users such as the sender and receiver, so the security of the password is guaranteed. The user's multimedia content file has sufficient randomness and cannot be predicted, so the fact that it cannot be reproduced guarantees safety in information theory. The security of the encryption of the present invention can be proven by the following Shannon formula.

Second, the encryption of the present invention is an economical and user-friendly encryption because it generates an encryption key and performs encryption using a multimedia content file that can be produced in everyday life without introducing an expensive random number generator in small devices such as smartphones. Services can be provided.

Third, the present invention is an encryption technology that can flexibly respond to various multimedia information and data exchanged in the encryption technology required in sensor networks, NFT services, metaverse, autonomous vehicles, drones, remote medicine, etc., which will be established in the service market in the future. technology can be provided.

fourth. In the future, we can provide a cryptographic system that can be flexibly used in the face of technological innovations such as the emergence of quantum computers.

Fifth, unlike existing encryption methods, it is possible to provide an encryption system that allows users to easily use the plaintext of the multimedia content to be encrypted and the multimedia content to generate an encryption key on their own device.

Sixth, the present invention is a common key encryption method, which has fast processing speed, small number of keys to manage, and easy key management.

From the above-described content, it can be seen that various changes and modifications can be made by those skilled in the art without departing from the technical idea of the present invention.

For example, a stronger password of the present invention can be generated by combining embodiments of the present invention.

The above combined embodiments are described below.

In order to encrypt the plaintext, the sender generates a plaintext ciphertext using the plaintext encryption key and his/her media content file, and generates a second encryption key to re-encrypt the plaintext encryption key to re-encrypt the plaintext encryption key. It's a method. The second encryption key becomes a key for delivering the plaintext encryption key. When the plaintext ciphertext and secret key ciphertext generated in the above combination embodiment, and the Besson ciphertext and secret key ciphertext encrypted with the plaintext cipherkey are transmitted to the recipient, the recipient who has received the four ciphertexts of the sender sends his/her common key for delivery. The public key is transmitted to the sender. The second encryption key used to encrypt the sender's plain text encryption key is encrypted using the recipient's common key delivery public key and transmitted to the recipient. The receiver decrypts the sender's plain text encryption key from an encryption file in which the sender's second encryption key is encrypted with the receiver's common key delivery public key, and then uses the decrypted plain text encryption key file of the sender to The sender's plaintext ciphertext can be decrypted into the sender's plaintext. Generation of each ciphertext and decryption of the plaintext can be performed by the method described in the above embodiment.

Claims

In an encryption system on a network-connected sender or receiver device,

The sender or receiver device includes one or more of a smartphone, tablet, smartwatch, PC, CCTV, GPS, and sensor device, and the sender device includes a memory means capable of storing the plain text that is the subject of the sender's encryption,

means wherein the plaintext subject to encryption by the sender includes one or more content files of character text files, photo image files, audio files, and video files;

For the plain text that is the subject of encryption of the sender, the content file provided by the receiver or sender is used as an encryption key for encrypting the sender's plain text, and the content file of the sender or receiver used as the encryption key is a text file of character data, a photo, means for generating a ciphertext of the sender's plaintext, including at least one of a graphic image, audio, or video file;

It includes means for decrypting the ciphertext of the sender's plaintext on the recipient's device,

The means for generating the ciphertext of the sender's plaintext is,

(a) An encryption key for encrypting the sender's plaintext means generating an encrypted text of the sender's plaintext using the content file provided by the sender and a secret key set by the sender on the sender's content file, or

(b) means for generating an encrypted text of the sender's plaintext using the content file provided by the recipient and a secret key set by the recipient on the recipient's content file; or

(c) An encryption key for encrypting the sender's plaintext means generating an encrypted text of the sender's plaintext using a content file provided by the sender and a secret key set by the receiver on the sender's content file, or

(d) an encryption key for encrypting the sender's plaintext, means for generating an encrypted text of the sender's plaintext using the content file provided by the recipient and a secret key set by the sender on the recipient's content file,

A password system comprising one or more of the following.
According to claim 1,

(a) An encryption key for encrypting the sender's plaintext means generating an encrypted text of the sender's plaintext using the content file provided by the sender and a secret key set by the sender on the content file provided by the sender. silver,

The sender, who transmits the ciphertext of the sender's plaintext, uses a content file stored in the sender's device as an encryption key used to encrypt the sender's plaintext, and the sender uses a content file stored in the sender's device to encrypt the sender's plaintext. A means for the sender to provide and use a secret key containing the encryption start point information set by touch to the receiver,

An encryption key for encrypting the sender plaintext provided by the sender includes at least one of media content files such as text files, photo files, graphic image files, audio files, and video files of character data,

The encryption start point information designated by the sender by touching the media content file stored in the sender device is displayed on the screen of the sender device, and then the sender touches and sets the encryption start point on the displayed content file. , a means of using the bit string of the start point set by the sender on the content file as the start point information of the encryption key for encrypting the sender's plain text,

Means for using a content file provided by the sender as an encryption key for encrypting the sender's plain text and using encryption key start point information set by a touch on the content file by the sender as a secret key for encrypting the sender's plain text;

The information on the encryption start point touched and set by the sender includes one or more of pixel coordinates, color value, specific time, character code, and numerical data of the point touched by the sender on the content file provided by the sender. Means containing one or more of data in units of specific bits, bytes, or words among the binary data constituting the media content file provided by the sender;

The means for generating the ciphertext of the sender's plaintext is a means for the sender to sequentially calculate and generate the ciphertext of the sender's plaintext by exclusive ORing the bit string of the sender's plaintext and the bit string of the encryption start point touched by the sender on the content file provided by the sender. ,

Means for transmitting the generated ciphertext of the sender's plaintext, a content file that is an encryption key for encrypting the sender's plaintext, and a secret key for encrypting the sender's plaintext to the recipient's device;

A password system characterized by having a.
According to claim 1,

(b) The encryption key for encrypting the sender's plaintext is a means for generating the encrypted text of the sender's plaintext using the content file provided by the recipient and the secret key set by the recipient on the recipient's content file. ,

The receiver provides a content file stored in the recipient's device as an encryption key used to encrypt the sender's plaintext to the sender, and the receiver provides the content file used to encrypt the sender's plaintext provided by the receiver. A means for the recipient to provide and use a secret key containing the encryption start point information set by touch to the sender,

An encryption key for encrypting the sender's plaintext provided by the receiver includes at least one of media content files such as text files, photo files, graphic image files, audio files, and video files of character data,

The encryption start point information of the sender's plain text set by the receiver is touched, and after displaying the media content file stored in the receiver device on the screen of the receiver device, the receiver starts encryption on the displayed content file. A means of touching and setting a point and using the bit string of the start point touched and set by the receiver on the content file as start point information of an encryption key for encrypting the sender's plain text,

Means for using the recipient's content file as an encryption key for the sender's plaintext and using the encryption key start point information set by the recipient's touch on the content file provided by the recipient as a secret key for encryption of the sender's plaintext,

The encryption start point information set by the receiver by touching on the content file includes one or more of pixel coordinates, color value, specific time, character code, and numerical data of the point touched by the sender on the content file, or the recipient Means containing one or more of data in specific bit, byte, or word units among the binary data that constitutes the provided media content file;

The means for generating the ciphertext of the sender's plaintext is a means for sequentially calculating and generating the ciphertext of the sender's plaintext by exclusive ORing the bit string of the sender's plaintext and the bit string of the encryption start point touched by the receiver on the content file provided by the receiver.

Means for the recipient to transmit a content file provided by the recipient and a secret key containing encryption start point information set by a touch on the content file provided by the recipient to the sender's device,

A password system characterized by having a.
According to claim 1,

(c) An encryption key for encrypting the sender's plaintext means generating an encrypted text of the sender's plaintext using the content file provided by the sender and a secret key set by the receiver on the sender's content file, or

(d) The encryption key for encrypting the sender's plaintext is a means for generating an encrypted text of the sender's plaintext using the content file provided by the recipient and a secret key set by the sender on the recipient's content file,

An encryption key used by the sender or receiver to encrypt the sender's plaintext.

Or, a content file stored in the recipient's device is provided to the sender or recipient, and encryption start point information set by the sender or recipient is touched on the content file used to encrypt the sender's plain text provided by the sender or receiver. A means for the sender or receiver to provide and use the specified secret key to the sender,

An encryption key for encrypting the sender plaintext provided by the sender or receiver includes at least one of media content files such as text files, photo files, graphic image files, audio files, and video files of character data,

The encryption start point information of the sender's plain text set by the sender or the receiver by touching the media content file stored in the sender or receiver device is displayed on the screen of the sender or receiver device, and then the displayed content Means that the sender or receiver touches and sets an encryption start point on a file and uses the bit string of the start point touched and set on the content file by the sender or receiver as start point information of an encryption key for encrypting the sender's plain text,

The content file of the sender or receiver is used as an encryption key for the sender's plain text, and the encryption key start point information set by the sender or the receiver by touching on the content file provided by the sender or receiver is used as a secret key for encryption of the sender's plain text. means of doing,

The encryption start point information set by the sender or the receiver by touching on the content file includes one or more of pixel coordinates, color value, specific time, character code, and numerical data of the point touched by the sender on the content file. Means containing one or more of data in units of specific bits, bytes, or words among the binary data constituting the media content file provided by the sender or receiver;

The means for generating the ciphertext of the sender's plaintext is generated by sequentially calculating the exclusive OR of the bit string of the sender's plaintext and the bit string of the encryption start point touched by the sender or receiver on the content file provided by the sender or receiver. means of doing,

The sender or receiver transmits a content file provided by the sender or receiver and a secret key containing encryption start point information set by a touch by the sender or receiver on the content file provided by the sender or receiver to the sender's device. method,

A password system characterized by having a.
According to claim 1,

The ciphertext of the sender's plaintext generated by the means for generating the ciphertext of the sender's plaintext is transmitted by the sender to the recipient's device, and the receiver stores the received ciphertext of the sender's plaintext in the recipient's information device. A means for selecting a content file and calculating the bit string of the received plaintext ciphertext of the sender and the bit string of the content file selected by the receiver by exclusive OR to generate a content file with the same length as the ciphertext of the sender's plaintext.

A password system comprising:
According to claim 1,

An encryption system, wherein the means for generating the ciphertext of the sender's plaintext further includes means for generating the ciphertext of the voice or video plaintext of the sender or the receiver.
According to claim 6,

A means for generating an encrypted text of the voice or video plaintext of the sender or receiver,

Means for the sender or the receiver to exchange the encryption key and secret key for encryption of the voice or video plain text with each other before starting a call,

An encryption key for encrypting the voice or video plaintext of the sender or receiver is a content file provided by the sender or receiver and includes at least one of text files, photo files, graphic image files, audio and video files of text data. ,

A password system comprising:
According to claim 6,

The means for generating an encrypted text of the sender's or receiver's voice or video plaintext,

The sender or receiver, who has exchanged the encryption key and secret key of the sender or receiver, uses the secret key on his or her own device to confirm an encryption start point for encryption of the voice or video plain text of the sender or receiver,

The bit string of the voice or video plaintext of the sender and the receiver and the bit string of the encryption key of the sender or receiver are calculated by exclusive OR to generate ciphertext of the voice or video plaintext of the sender or receiver, and the generated ciphertext is sent to the sender or receiver. A means of transmission to the recipient.
According to claim 8,

An encryption system, characterized in that the means for checking the encryption start point of the plain text encryption key file includes means that can be executed automatically by a software program or manually by the sender or receiver.
In the encryption method on a network-connected sender or receiver device,

The sender or receiver device includes one or more of a smartphone, tablet, smartwatch, PC, CCTV, GPS, and sensor device, and the sender device has a memory capable of storing the plaintext that is the target of the sender's encryption,

The plaintext subject to encryption by the sender includes one or more content files of text text files, photo image files, audio files, and video files,

For the plain text that is the subject of encryption of the sender, the content file provided by the receiver or sender is used as an encryption key for encrypting the sender's plain text, and the content file of the sender or receiver used as the encryption key is a text file of character data, a photo, Generate a ciphertext of the sender's plaintext containing at least one of a graphic image, an audio, or a video file,

It includes a method of decrypting the ciphertext of the sender's plaintext on the recipient's device, and the method of generating the ciphertext of the sender's plaintext

(a) The encryption key for encrypting the sender's plaintext is a method of generating the encrypted text of the sender's plaintext using the content file provided by the sender and the secret key set by the sender on the sender's content file, or

(b) A method of generating an encrypted text of the sender's plaintext using the content file provided by the receiver and a secret key set by the receiver on the receiver's content file, or

(c) An encryption key for encrypting the sender's plaintext is a method of generating an encrypted text of the sender's plaintext using a content file provided by the sender and a secret key set by the receiver on the sender's content file, or

(d) a method of generating an encrypted text of the sender's plaintext using an encryption key for encrypting the sender's plaintext and a secret key set by the sender on the content file provided by the receiver and the receiver's content file;

An encryption method comprising one or more of the following.
According to claim 10,

(a) A method of generating an encrypted text of the sender's plaintext using an encryption key for encrypting the sender's plaintext and a secret key set by the sender on the content file provided by the sender and the content file provided by the sender. silver,

The sender, who transmits the ciphertext of the sender's plaintext, uses a content file stored in the sender's device as an encryption key used to encrypt the sender's plaintext, and the sender uses a content file stored in the sender's device to encrypt the sender's plaintext. The sender provides the receiver with a secret key containing the encryption start point information set by touch, and uses it.

The encryption key for encrypting the sender plaintext provided by the sender includes at least one of media content files such as text files, photo files, graphic image files, audio files, and video files of character data,

The encryption start point information designated by the sender by touching the media content file stored in the sender device is displayed on the screen of the sender device, and then the sender touches and sets the encryption start point on the displayed content file. , The bit string of the start point set by the sender on the content file is used as the start point information of the encryption key for encrypting the sender's plain text,

Using the content file provided by the sender as an encryption key for encrypting the sender's plaintext, and using the encryption key start point information set by the sender by touching on the content file as a secret key for encrypting the sender's plaintext,

The information on the encryption start point touched and set by the sender includes one or more of pixel coordinates, color value, specific time, character code, and numerical data of the point touched by the sender on the content file provided by the sender. It contains one or more of the data in units of specific bits, bytes, or words among the binary data that constitutes the media content file provided by the sender,

The means for generating the ciphertext of the sender's plaintext is generated by the sender sequentially calculating an exclusive OR of a bit string of the sender's plaintext and a bit string of an encryption start point touched by the sender on a content file provided by the sender,

An encryption method wherein the sender transmits the generated ciphertext of the sender's plaintext, a content file that is an encryption key for encrypting the sender's plaintext, and a secret key for encrypting the sender's plaintext to the recipient's device.
According to claim 10,

(b) The encryption key for encrypting the sender's plaintext is a method of generating the encrypted text of the sender's plaintext using the content file provided by the recipient and the secret key set by the recipient on the recipient's content file.

The receiver provides a content file stored in the receiver's device as an encryption key used to encrypt the sender's plaintext to the sender, and the receiver provides the content file used to encrypt the sender's plaintext provided by the receiver. The receiver provides the sender with a secret key containing the encryption start point information set by touch, and uses it.

The encryption key for encrypting the sender's plaintext provided by the receiver includes at least one of media content files such as text files, photo files, graphic image files, audio files, and video files of character data,

The encryption start point information of the sender's plain text set by the receiver is touched, and after displaying the media content file stored in the receiver device on the screen of the receiver device, the receiver starts encryption on the displayed content file. The point is set by touch and the bit string of the start point set by the receiver on the content file is used as the start point information of the encryption key for encrypting the sender's plain text,

Using the recipient's content file as an encryption key for the sender's plaintext and using the encryption key start point information set by the recipient by touching on the content file provided by the recipient as a secret key for encryption of the sender's plaintext,

The encryption start point information set by the receiver by touching on the content file includes one or more of pixel coordinates, color value, specific time, character code, and numerical data of the point touched by the sender on the content file, or the recipient Among the binary data that constitutes the provided media content file, it contains one or more data in units of specific bits, bytes, or words,

The means for generating the ciphertext of the sender's plaintext sequentially calculates and generates the ciphertext of the sender's plaintext by exclusive ORing the bit string of the sender's plaintext and the bit string of the encryption start point touched by the receiver on the content file provided by the receiver,

The recipient transmits a content file provided by the recipient and a secret key containing encryption start point information touched by the recipient on the content file provided by the recipient to the sender's device.

An encryption method comprising:
According to claim 10,

The ciphertext of the sender's plaintext generated by the method of generating the ciphertext of the sender's plaintext is transmitted by the sender to the recipient's device, and the receiver stores the received ciphertext of the sender's plaintext in the recipient's information device. A method of selecting a content file and calculating the bit string of the received plaintext ciphertext of the sender and the bit string of the content file selected by the receiver by exclusive OR to generate a content file with the same length as the ciphertext of the sender's plaintext.

A cryptographic method comprising:
According to claim 10,

The method of generating an ciphertext of the sender's plaintext further includes a method of generating an ciphertext of the voice or video plaintext of the sender or the receiver.
According to claim 14,

A method of generating an encrypted text of the voice or video plaintext of the sender or receiver,

The sender or receiver may exchange the encryption key and secret key for encryption of the voice or video plain text with each other before starting the call,

The encryption key for encrypting the voice or video plaintext of the sender or receiver is a content file provided by the sender or receiver and includes at least one of text files, photo files, graphic image files, audio and video files of text data. Characterized encryption method.
According to claim 14,

The method for generating ciphertext of the sender or receiver voice or video plaintext is,

The sender or receiver, who has exchanged the encryption key and secret key of the sender or receiver, uses the secret key on his/her device to confirm the encryption start point for encryption of the sender's or receiver's voice or video plain text,

The bit string of the voice or video plaintext of the sender or receiver and the bit string of the encryption key of the sender or receiver are calculated by exclusive OR to generate ciphertext of the voice or video plaintext of the sender or receiver, and the generated ciphertext is sent to the sender or receiver. A cryptographic method characterized by transmission to a recipient.
According to claim 16,

An encryption method, characterized in that the method of checking the encryption start point of the plaintext encryption key file includes a method that can be executed automatically by a software program or manually by the sender or receiver.