KR101924047B1 - Encryption method and apparatus using the same, decryption method and appratus using the same - Google Patents

Abstract

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an encryption method, and more particularly, to an encryption method capable of decrypting data without sharing an encryption key used for data encryption, and a transmitting apparatus, a decrypting method, and a receiving apparatus using the same.
In the encrypting method in the transmitting apparatus according to an embodiment of the present invention, the transmitting apparatus receives the data d, applies an encryption function E to the input data d, d), scrambling the data generated in the encrypted data E (d) and the encrypting step, and transmitting the scrambled data to a receiving device.

Description

BACKGROUND OF THE INVENTION 1. Field of the Invention [0001] The present invention relates to an encryption method, a transmitting apparatus, a decoding method, and a receiving apparatus using the same,

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an encryption method, and more particularly, to an encryption method capable of decrypting data without sharing an encryption key used for data encryption, and a transmitting apparatus, a decrypting method, and a receiving apparatus using the same.

The contents described in this section merely provide background information on the present embodiment and do not constitute the prior art.

Recently, as information such as various documents and data is digitized by computers, and as the Internet, e-mail, and digital storage media are developed, there is an opportunity to obtain desired data more quickly and easily.

However, because of the nature of these digital data, it is not only easy to create the same copy or modified version as the original, but also it is easy to distribute it. Therefore, illegal copying and distribution, There is a problem that can lead to weakening of competitiveness. In particular, as the construction of a LAN (local area network) or a KMS (Knowledge Management System) has progressed rapidly within the enterprise, the information and the data in the enterprise have been exchanged frequently. Therefore, The possibility of institutional information disclosure is increasing even more.

Therefore, the demand for security technology for data is rapidly increasing, and accordingly, various techniques for enhancing security of data are being developed.

It is generally known that the data security techniques to date transmit data to the receiving end after the data is encrypted using the encryption key, and the receiving end decrypts the data using the encryption key. In this case, the public key encryption method and the secret key encryption method can be classified according to whether the encryption key is disclosed or not, and various key management techniques are introduced.

However, in the case of the data security technique using the encryption key up to now, there is a problem that the encryption key used in the encryption is shared in advance or the rule for generating the encryption key is shared, so that there is a high possibility of being exposed to the outside due to illegal access .

Therefore, there is a need to develop a technology capable of encrypting and decrypting data without sharing the encryption key used in encrypting the data and without sharing the rules for generating the encryption key.

Korean Patent Publication No. 10-2002-0073810, published on September 28, 2002 (name: storage medium for content protection, recording and reproducing method and apparatus on the storage medium thereof)

It is an object of the present invention to provide an encryption method capable of decrypting data without sharing an encryption key used for data encryption, a transmitting apparatus using the same, a decrypting method using the same, and a receiving apparatus using the same. The purpose is to provide.

In addition, the transmitting apparatus of the present invention not only scrambles data but scrambles and transmits various values generated in the encryption procedure, and the receiving apparatus descrambles the received values, and then encrypts the encrypted data using the received values And a transmitting apparatus, a decoding method, and a receiving apparatus using the same.

However, the object of the present invention is not limited to the above-mentioned objects, and other objects not mentioned can be clearly understood from the following description.

According to another aspect of the present invention, there is provided an encryption method in a transmission apparatus, the method comprising: receiving data d from the transmission apparatus; Encrypting the data (d) by applying an encryption function (E) to the input data (d); Scrambling the encrypted data E (d) and data generated in the encrypting step; And transmitting the scrambled data to a receiving device.

The encrypting may include generating a random value z; Applying the generated random value z to a key derivation function (KDF) to generate an encryption key; And encrypting the data (d) using the generated encryption key and the encryption function (E).

In addition, the encrypting step may include generating a hash value H (d) for the data d; And encrypting the random value z using the hash value H (d) and the encryption function E.

The scrambling step may include a step of scrambling a value E _H (z) obtained by encrypting the encrypted data E (d), the hash value H (d) for the data d, Can be scrambled.

Further comprising constructing a plurality of sets including a cryptographic function (E), a hash function (H), and a key derivation function (KDF), said encrypting step and said scrambling step May be accomplished by selecting any one of the sets.

The method may further include sharing the plurality of sets with the receiving apparatus.

According to an aspect of the present invention, there is provided a transmission apparatus using an encryption method including: a data input unit receiving data d to be encrypted; An encryption processing unit for encrypting the data d by applying the encryption function E to the input data d; A scrambling unit scrambling the encrypted data E (d) and the data generated in the encrypting step; And a transmitter for transmitting the scrambled data to a receiving apparatus.

According to an aspect of the present invention, there is provided a computer-readable recording medium having recorded thereon a program for executing an encryption method, Encrypting the data (d) by applying an encryption function (E) to the input data (d); Scrambling the encrypted data E (d) and data generated in the encrypting step; And transmitting the scrambled data.

According to another aspect of the present invention, there is provided a decoding method in a receiving apparatus, comprising: receiving data scrambled from a transmitting apparatus by the receiving apparatus; Descrambling the scrambled data; Generating an encryption key using the random value (z) identified in the descrambled data; Decrypting the encrypted data E (d) in the descrambled data using the generated encryption key; And verifying the decrypted data (d).

The step of generating the encryption key may include extracting a hash value H (d) of the data d from the descrambled data, Identifying a random value z using a hash value H (d) of the data d; And generating the encryption key by applying the identified random value z to a key derivation function (KDF).

The verifying may further include applying the data d to a hash function H to generate a hash value H (d); And comparing the generated hash value H (d) with a hash value H (d) of the data d extracted from the decrambled data.

According to an aspect of the present invention, there is provided a receiving apparatus using an encryption method, the receiving apparatus including: a receiving unit for receiving scrambled data from a transmitting apparatus; A descrambling unit for descrambling the scrambled data; And generating an encryption key using the random value (z) identified in the descrambled data through the descrambling unit, and generating encrypted data E (d) from the descrambled data using the generated encryption key, And a decoding processing unit for decoding the decoded data d and verifying the decoded data d.

According to an aspect of the present invention, there is provided a computer-readable recording medium having recorded thereon a program for executing a decoding method, the method comprising: receiving scrambled data; Descrambling the scrambled data; Generating an encryption key using the random value (z) identified in the descrambled data; Decrypting the encrypted data E (d) in the descrambled data using the generated encryption key; And verifying the decrypted data (d).

According to the encrypting method of the present invention and the transmitting device, the decrypting method and the receiving device using the encrypting method of the present invention, data is encrypted through an encryption key generated based on a random value rather than a public key, Thereby solving the security problem.

In addition, according to the present invention, not only the data to be encrypted but also all the values generated in the encryption process are scrambled and transmitted to the receiving apparatus, so that a security problem that may be caused by data transmission and reception can be prevented, It can be done more efficiently.

In addition, various effects other than the above-described effects can be directly or implicitly disclosed in the detailed description according to the embodiment of the present invention to be described later.

1 is a schematic block diagram of an encryption system according to an embodiment of the present invention.
2 is a block diagram showing a main configuration of a transmitting apparatus according to an embodiment of the present invention.
3 is a block diagram showing more specifically the role of the encryption processing unit of the present invention.
4 is a block diagram illustrating a main configuration of a receiving apparatus according to an embodiment of the present invention.
5 is a flowchart illustrating an encryption method in a transmitting apparatus according to an embodiment of the present invention.
6 is an exemplary diagram illustrating an encryption method in a transmitting apparatus according to an embodiment of the present invention.
7 is a flowchart illustrating a decoding method in a receiving apparatus according to an embodiment of the present invention.

BRIEF DESCRIPTION OF THE DRAWINGS For a more complete understanding of the nature and advantages of the present invention, reference should be made to the following detailed description taken in conjunction with the accompanying drawings, in which:

In the following description and the accompanying drawings, detailed description of well-known functions or constructions that may obscure the subject matter of the present invention will be omitted. It should be noted that the same constituent elements are denoted by the same reference numerals as possible throughout the drawings.

The terms and words used in the following description and drawings are not to be construed in an ordinary sense or a dictionary, and the inventor can properly define his or her invention as a concept of a term to be described in the best way It should be construed as meaning and concept consistent with the technical idea of the present invention. Therefore, the embodiments described in the present specification and the configurations shown in the drawings are merely the most preferred embodiments of the present invention, and not all of the technical ideas of the present invention are described. Therefore, It is to be understood that equivalents and modifications are possible.

Also, terms including ordinal numbers such as first, second, etc. are used to describe various elements, and are used only for the purpose of distinguishing one element from another, Not used. For example, without departing from the scope of the present invention, the second component may be referred to as a first component, and similarly, the first component may also be referred to as a second component.

In addition, when referring to an element as being "connected" or "connected" to another element, it means that it can be connected or connected logically or physically. In other words, it is to be understood that although an element may be directly connected or connected to another element, there may be other elements in between, or indirectly connected or connected.

Also, the terminology used herein is for the purpose of describing particular embodiments only and is not intended to be limiting of the invention. The singular expressions include plural expressions unless the context clearly dictates otherwise. It is also to be understood that the terms such as " comprising " or " having ", as used herein, are intended to specify the presence of stated features, integers, It should be understood that the foregoing does not preclude the presence or addition of other features, numbers, steps, operations, elements, parts, or combinations thereof.

In addition, embodiments within the scope of the present invention include computer-readable media having computer-executable instructions or data structures stored on computer-readable media. Such computer-readable media can be any available media that is accessible by a general purpose or special purpose computer system. By way of example, and not limitation, such computer-readable media can comprise RAM, ROM, EPROM, CD-ROM or other optical disk storage, magnetic disk storage or other magnetic storage devices, or in the form of computer- But is not limited to, a physical storage medium such as any other medium that can be used to store or communicate certain program code means of the general purpose or special purpose computer system, .

In the following description and claims, " network " or " communication network " is defined as one or more data links that allow electronic data to be transmitted between computer systems and / or modules. When the information is transmitted or provided to a computer system via a network or other (wired, wireless, or a combination of wired or wireless) communication connection, the connection may be understood as a computer-readable medium. Computer readable instructions include, for example, instructions and data that cause a general purpose computer system or special purpose computer system to perform a particular function or group of functions. The computer executable instructions may be binary, intermediate format instructions, such as, for example, assembly language, or even source code.

Now, the main configuration of the encryption system according to the embodiment of the present invention will be described.

1 is a schematic block diagram of an encryption system according to an embodiment of the present invention.

Referring to FIG. 1, an encryption system 300 according to an embodiment of the present invention provides encryption and decryption methods between a transmitting apparatus 100 and a receiving apparatus 200.

The transmitting apparatus 100 and the receiving apparatus 200 according to the present invention are classified according to the transmission and reception of information. The transmitting apparatus 100 encrypts the data and transmits the encrypted data to the receiving apparatus 200, 200 receives and decrypts the encrypted data from the transmitting apparatus 100.

The transmitting apparatus 100 and the receiving apparatus 200 may be logically or physically connected to each other. In the case where the transmitting apparatus 100 and the receiving apparatus 200 are logically connected, for example, the transmitting apparatus 100 and the receiving apparatus 200 are implemented independently, And are connected to each other through an IP address or the like. At this time, the transmitting apparatus 100 and the receiving apparatus 200 may be devices applied to a server-client structure, a peer-to-peer structure, and the like. On the other hand, when the transmitting device 100 and the receiving device 200 are physically connected, they may be connected to each other via a USB cable, or each device may be implemented as a module and implemented in one device. In this case, it is possible to perform a process of encrypting, decrypting, and processing data transmitted and received through a path through which the transmitting apparatus 100 and the receiving apparatus 200 are physically connected.

The transmitting device 100 and the receiving device 200 of the present invention can also be used in a variety of forms such as a personal computer, a laptop computer, a handheld device, a multiprocessor system, a microprocessor-based or programmable consumer electronics, The present invention may be embodied in a network computing environment having various types of computer system configurations including computers, mainframe computers, mobile telephones, PDAs, pagers, and the like.

In addition, the transmitting apparatus 100 and the receiving apparatus 200 of the present invention can be applied to a mobile phone such as a smart phone, a tablet PC, a PDA (personal digital assistant), a portable multimedia player (PMP) Fixed terminals such as smart TVs, desktop computers, and the like can be used as well as terminals. In this case, when the encryption system 300 of the present invention is implemented in a server-client manner, any one of the transmitting apparatus 100 and the receiving apparatus 200 acts as a server, Can play a role. Also, when the encryption system 300 of the present invention is implemented in a peer-to-peer manner, the transmitting apparatus 100 and the receiving apparatus 200 may be implemented as any one of the mobile terminal and the fixed terminal described above.

In this case, when any one of the transmitting apparatus 100 and the receiving apparatus 200 of the present invention is implemented as a server, the server at this time has the same hardware configuration as a typical Web server or a network server can do. However, it may include a program module implemented through a language such as C, C ++, Java, Visual Basic, Visual C, or the like in software.

In addition, the transmitting apparatus 100 and the receiving apparatus 200 of the present invention can be connected through a wired / wireless network. The wired / wireless network may be connected to a mobile network including a wired / wireless access network (not shown) and a core network (not shown), and may include an external network such as an Internet network (not shown). The wired / wireless access network (not shown) constituting the mobile network is an access network that performs wired / wireless communication with the transmitting apparatus 100 and the receiving apparatus 200. The wired or wireless access network includes a base station (BS), a base transceiver station (BTS) , A NodeB, an eNodeB, and the like, and a base station controller such as a base station controller (BSC) and a radio network controller (RNC).

Alternatively, the digital signal processing unit and the radio signal processing unit integrally implemented in the base station may be divided into a digital unit (hereinafter referred to as DU) and a radio unit (hereinafter referred to as RU) A plurality of RUs (not shown) may be provided in each of the regions, and a plurality of RUs (not shown) may be connected to a centralized DU (not shown).

In addition, a core network (not shown) constituting a mobile network together with a wired / wireless access network (not shown) performs a role of connecting a wired / wireless access network (not shown) and an external network such as an Internet network (not shown).

As described above, the core network (not shown) is a network system that performs main functions for mobile communication services such as mobility control and switching between wired / wireless access networks (not shown). The core network includes circuit switching or packet switching packet switching, and manages and controls packet flow within the mobile network. The core network (not shown) manages inter-frequency mobility and plays a role for interworking with traffic in an access network (not shown) and a core network (not shown) and other networks such as the Internet It is possible. The core network (not shown) may further include a Mobile Switching Center (MSC), a Home Location Register (HLR), a Mobile Mobility Entity (MME), and a Home Subscriber Server (HSS). In addition, an Internet network (not shown) means a public network, that is, a public network, in which information is exchanged according to the TCP / IP protocol.

The encryption system 300 according to the embodiment of the present invention has been schematically described above.

Hereinafter, the main configuration and operation of the transmission apparatus 100 according to the embodiment of the present invention will be described with reference to FIG. 2 and FIG.

FIG. 2 is a block diagram showing a main configuration of a transmitting apparatus according to an embodiment of the present invention, and FIG. 3 is a block diagram showing more specifically the role of the encryption processing section of the present invention.

Referring to FIG. 2, a transmitting apparatus 100 of the present invention includes a data input unit 110, an encryption processing unit 120, a scrambling unit 130, a transmitting unit 140, and various information generated in an encryption process And a transmission storage unit 150 that manages and manages data.

First, the data input unit 110 receives data to be transmitted. The input data may be directly input according to an input of a user, or data transmitted from another device may be used. The data input unit 110 transmits the input data to the encryption processing unit 120.

The encryption processing unit 120 performs encryption for the input data. 3, the encryption processing unit 120 generates the random value z through the random value generating unit 121. [ Here, the random value z is a value randomly generated by the random value generator 120, not a value set according to a predetermined rule or function with the receiving apparatus 200. In this case, the random value z may be generated first based on the seed and generated based on the seed. For example, assuming that the seed value is the initial value, the random value generator 121 generates a random value z Can be generated. Here, the random value generator 121 may be configured by, for example, a linear feedback shift register (LFSR), but is not limited thereto.

The encryption key generating unit 122 applies the generated random value z to a key derivation function (KDF) to generate an encryption key. The key derivation function used by the transmission apparatus 100 of the present invention may be, for example, a block cipher-based key derivation function. The block cipher key derivation function is a function that the input value x composed of one block is extended to t blocks, and the input value of n bits can be expanded to the length of nt bits through the multi-block output function. As an example of such a block-based key derivation function, a counter mode, a feedback mode, a double-pipeline Iteration mode, and an Milenage mode can be applied. In particular, the encryption key generation unit 122 of the present invention generates an extended bit encryption key by applying the generated random value z to the input value x.

The encryption performing unit 123 encrypts the input data using the encryption key generated through the encryption key generating unit 122 to generate the encrypted data E (d). In the encryption process, data can be encrypted using a predetermined encryption function (E).

The encryption performing unit 123 of the present invention applies the input data d to the hash function H to generate a hash value H (d). The hash function (H) is an algorithm for mapping data of arbitrary length to fixed length data. The encrypted hash function has MD5 and SHA series, and the non-encrypted hash function is CRC32.

The encryption performing unit 123 of the present invention encrypts the random value z generated by the random value generating unit 121 using the generated hash value _H (z).

In the present invention, the random value (z), which is the seed value used for generating the encryption key, and the encryption key are not shared between the transmission apparatus 100 and the reception apparatus 200. Instead, the transmitting apparatus 100 and the receiving apparatus 200 may use the key derivation function used in the encryption process, the encryption function (E), the hash function The function H is shared in advance.

Therefore, when the transmitting apparatus 100 according to the present invention transmits the encrypted data E (d) to the receiving apparatus 200, the receiving apparatus 200 decrypts the encrypted data E (d) The hash value H (d) obtained by applying the data d to the hash function H together with the encrypted data E (d) and the hash value H (d) And transmits the value E _H (z) obtained by encrypting the random value z to the receiving apparatus 200 by applying the random number z.

At this time, the scrambling unit 130 of the present invention adds the data d to the hash function H together with the data E (d) encrypted by the encryption processing unit 120 in order to further enhance security And applies the hash value H (d) and the hash value H (d) to the encryption key to scramble the value E _H (z) obtained by encrypting the random value z. At this time, the scrambling unit 130 of the present invention performs a scrambling process of scrambling each value according to a predefined scramble pattern.

The transmitting unit 140 transmits the encrypted data E (d) through the scrambling unit 130, the hash value H (d) obtained by applying the data d to the hash function H, and the hash value H (d)) is applied as an encryption key and a value (E _H (z)) obtained by encrypting the random value z is different.

At this time, the scramble pattern is shared between the transmitting apparatus 100 and the receiving apparatus 200, and even if the data transmitted from the transmitting apparatus 100 to the receiving apparatus 200 is exposed to an arbitrary third party, It is difficult to extract desired information from the corresponding data.

Also, the encryption processing unit 120 of the present invention can solve the security problem due to the exposure of the encryption key primarily by encrypting the data through the encryption key generated based on the random value (z) rather than the public key scheme The scrambling unit 130 notifies the encrypted data E (d) and the data d to the hash function H instead of scrambling only the encrypted data E (d) generated in the encryption procedure, Scrambled value E _H (z) obtained by encrypting the random value z by applying the hash value H (d) and the hash value H (d) applied to the reception apparatus 200 as an encryption key, Thus, it is possible to prevent a security problem that may be caused by data transmission / reception, thereby further enhancing data security.

Meanwhile, the transmission storage unit 150 stores and manages various data generated in performing the encryption procedure in the transmission apparatus 100. For example, the transmission storage unit 150 of the present invention may store and manage the input data, the encryption function E, the hash function H, and the like necessary for encrypting the data.

In particular, the transmission storage unit 150 of the present invention stores and manages a set of functions for encryption including an encryption function E, a hash function H, and a key derivation function KDF as shown in Table 1 below. can do.

Set order Encryption function (E) Hash function (H) Key derivation function (KDF) Set1. E1 H3 KDF1 Set2. E2 H5 KDF4

The transmission storage unit 150 of the present invention can select and set any one of a plurality of sets of encryption function E, hash function H and key derivation function KDF The encryption processing unit 120 and the scrambling unit 130 can perform the encryption procedure using the encryption function E1, the hash function H3, and the key derivation function KDF1 set in the set of set functions, for example, Set1. Here, the set of functions for encryption must be shared with the receiving apparatus 200 in advance, and the same set of functions must be set in advance between the transmitting apparatus 100 and the receiving apparatus 200.

The main configuration and operation of the transmitting apparatus 100 according to the embodiment of the present invention have been described above.

Hereinafter, the main configuration and operation of the receiving apparatus 200 according to the embodiment of the present invention will be described.

4 is a block diagram illustrating a main configuration of a receiving apparatus according to an embodiment of the present invention.

1 and 4, a receiving apparatus 200 according to an embodiment of the present invention includes a receiving unit 210, a descrambling unit 220, a decoding processing unit 230, a data processing unit 240, 250).

More specifically, the receiving unit 210 receives the encrypted data E (d) transmitted from the transmitting apparatus 100, the hash value H (d) applied to the hash function H, (z) by applying the hash value H (d) and the hash value H (d) as an encryption key to the scrambled data for the value E _H (z).

The receiving unit 210 transmits the received data to the descrambling unit 220.

The descrambling unit 220 of the present invention performs descrambling to restore the received data to the original arrangement according to a predetermined scramble pattern shared with the transmission apparatus 100. [ The encrypted data E (d), the hash value H (d) applied to the hash function H and the hash value H (d) are decrypted a value encrypted random value (z) by applying a key (E _H (z)) is therefore restored to its original place, the group of encrypted data from the arrangement set (E (d)), the hash function to the data (d) ( H) can extract the hash value (H (d)) and the hash value (H (d) (value (E _H (z encrypts and z)))) by applying the encryption key, the random value is applied to each.

In addition, since the receiving apparatus 200 of the present invention does not know the encryption key used for encryption in the transmitting apparatus 100, the transmitting apparatus 100 first performs a process of generating an encryption key used for encryption in the transmitting apparatus 100 do.

To this end, the receiving apparatus 200 of the present invention extracts a hash value H (d) for the data d from the data descrambled first through the decoding processing unit 230. The decryption processing unit 230 of the present invention decrypts the value H (d) obtained by encrypting the random value z by applying the hash value H (d) extracted from the descrambled data with the extracted hash value _H (z)) can be decoded to confirm the random value z.

Thereafter, the decryption processing unit 230 of the present invention applies the extracted random value z to the key derivation function to generate an encryption key. Thereafter, the decryption processing unit 230 of the present invention can decrypt the encrypted data E (d) confirmed by descrambling using the generated encryption key. Accordingly, even if the encryption key is not transmitted or received, the original data to be transmitted by the transmission apparatus 100 can be confirmed.

Also, the decryption processing unit 230 of the present invention performs the verification procedure using the hash value H (d) generated by applying the data d to the predetermined hash function H. In other words, the hash value H (d) is generated by applying the confirmed data d to the predetermined hash function H to generate the hash value H And compares the hash value H (d) to verify whether or not the decoding process is normally performed.

When the data to be transmitted by the transmitting apparatus 100 is confirmed through the above process, the data processing unit 240 of the present invention can process the result. For example, the data processing unit 240 of the present invention may perform a specific function according to the confirmed data, or may transmit the function to a device for performing a function.

In addition, the reception storage unit 250 of the present invention stores and manages various information generated in the decoding process as described above. For example, it is possible to store and manage set information for encryption shared with the transmission apparatus 100, and to store and manage a scramble pattern for descrambling. Also, various information derived from the decryption procedure can be stored and managed.

The main configuration and operation of the transmitting apparatus 100 and the receiving apparatus 200 according to the embodiment of the present invention have been described above.

On the other hand, the memory mounted on each device of the present invention stores information in the device. In one implementation, the memory is a computer-readable medium. In one implementation, the memory may be a volatile memory unit, and in other embodiments, the memory may be a non-volatile memory unit. In one implementation, the storage device is a computer-readable medium. In various different implementations, the storage device may comprise, for example, a hard disk device, an optical disk device, or any other mass storage device.

Although the present specification and drawings describe exemplary device configurations, the functional operations and subject matter implementations described herein may be embodied in other types of digital electronic circuitry, or alternatively, of the structures disclosed herein and their structural equivalents May be embodied in computer software, firmware, or hardware, including, or in combination with, one or more of the foregoing. Implementations of the subject matter described herein may be embodied in one or more computer program products, i. E. One for computer program instructions encoded on a program storage medium of the type for < RTI ID = 0.0 & And can be implemented as a module as described above. The computer-readable medium can be a machine-readable storage device, a machine-readable storage substrate, a memory device, or a combination of one or more of the foregoing.

Hereinafter, an encryption method according to an embodiment of the present invention will be described.

FIG. 5 is a flowchart for explaining an encryption method in a transmitting apparatus according to an embodiment of the present invention, and FIG. 6 is an exemplary diagram illustrating an encryption method in a transmitting apparatus according to an embodiment of the present invention.

2 and 5, a transmitting apparatus 100 according to an embodiment of the present invention receives data to be transmitted through a data input unit 110 (S101). The input data may be directly input according to an input of a user, or data transmitted from another device may be used.

In order to perform encryption on the input data, the encryption processing unit 120 of the transmission apparatus 100 generates a random value z (S103). Here, the random value z is a value arbitrarily generated by the transmitting apparatus 100, not a value set in accordance with a rule or a function set beforehand with the receiving apparatus 200. In this case, the random value z may be generated first based on the seed and may be generated based on the seed. For example, if the random value generation unit 121 of the encryption processing unit 120 uses the seed value as the initial value, The value z can be generated. Here, the random value generator 121 may be configured by, for example, a linear feedback shift register (LFSR), but is not limited thereto.

The encryption processing unit 120 of the transmitting apparatus 100 of the present invention applies the generated random value z to a key derivation function (KDF) to generate an encryption key (S105). The key derivation function used by the transmission apparatus 100 of the present invention may be, for example, a block cipher-based key derivation function. The block cipher key derivation function is a function that the input value x composed of one block is extended to t blocks, and the input value of n bits can be expanded to the length of nt bits through the multi-block output function. As an example of such a block-based key derivation function, a counter mode, a feedback mode, a double-pipeline Iteration mode, and an Milenage mode can be applied. In particular, the encryption processing unit 120 of the transmitting apparatus 100 of the present invention generates an extended bit encryption key by applying the generated random value z to the input value x.

The encryption processing unit 120 of the transmission apparatus 100 of the present invention encrypts data input in step S101 using the generated encryption key to generate encrypted data E (d) ( S107). In the process of encryption, a predetermined encryption function (E) is used.

Thereafter, the encryption processing unit 120 of the transmission apparatus 100 of the present invention applies the input data d to the hash function H to generate a hash value H (d) (S109). The hash function (H) is an algorithm for mapping data of arbitrary length to fixed length data. The encrypted hash function has MD5 and SHA series, and the non-encrypted hash function is CRC32.

The encryption processing unit 120 of the transmitting apparatus 100 of the present invention encrypts the random value z generated in step S103 by using the hash value H (d) generated in step S109 as an encryption key, _H (z)) (S111).

In the present invention, the random value (z), which is the seed value used for generating the encryption key, and the encryption key are not shared between the transmission apparatus 100 and the reception apparatus 200. Instead, the transmitting apparatus 100 and the receiving apparatus 200 may transmit the key derivation function, the encryption function, the hash function (H ) In advance.

Therefore, when the transmitting apparatus 100 according to the present invention transmits the encrypted data E (d) to the receiving apparatus 200, the receiving apparatus 200 decrypts the encrypted data E (d) The hash value H (d) obtained by applying the data d to the hash function H together with the encrypted data E (d) and the hash value H (d) And transmits the value E _H (z) obtained by encrypting the random value z to the receiving apparatus 200 by applying the random number z.

In order to further enhance security, the transmitting apparatus 100 according to the present invention transmits a hash value H (d) obtained by applying the data d to the hash function H together with the encrypted data E (z) by applying the hash value H (d) and the hash value H (d) as an encryption key, and transmits the scrambled value E _H (z). That is, the scrambling unit 130 of the transmitting apparatus 100 according to the present invention transmits the encrypted data E (d), the hash value H (d) obtained by applying the data d to the hash function H, And receives the value E _H (z) obtained by encrypting the random value z by applying the hash value H (d) as an encryption key to perform scrambling (S113). Here, the scrambling unit 130 of the transmitting apparatus 100 of the present invention scrambles each value according to a scramble pattern defined in advance.

That is, as shown in FIG. 6, the key derivation function is applied to the generated random value z to generate an encryption key, and the encrypted data (d) is encrypted using the generated encryption key Generates a hash value H (d) through the hash function H, and outputs the random value z to the generated hash function H the value (H (d)) the value (E _H (z)) encrypted using the encryption key is generated.

Here, the encryption function E used for encrypting the data d and the encryption function E used for encrypting the random value z may use the same encryption function. For the sake of convenience of explanation, a random value z, respectively, but each of the indicated random values z means one random value z. Then, the scrambled data C is generated by scrambling the derived values through the above-described process.

Through this scrambling, the hash value H (d), which is the encrypted data E (d) on the transmission data, the hash value H (d) which applies the data d to the hash function H, Key, the value E _H (z) obtained by encrypting the random value z is different, and it becomes difficult to extract the specific information from the transmission data.

Thereafter, the transmitting unit 140 of the transmitting apparatus 100 of the present invention transmits the scrambled data to the receiving apparatus 200 (S115).

At this time, the scramble pattern is shared between the transmitting apparatus 100 and the receiving apparatus 200, and even if the data transmitted from the transmitting apparatus 100 to the receiving apparatus 200 is exposed to an arbitrary third party, It is difficult to extract desired information from the corresponding data.

In addition, the transmitting apparatus 100 of the present invention can solve the security problem due to the exposure of the encryption key by encrypting the data through the encryption key generated based on the random value (z) rather than the public key scheme (H (H)) applied to the hash function (H), instead of only scrambling the encrypted data E (d) generated in the encryption procedure, (z) is applied to the receiving apparatus 200 by scrambling the value E _H (z) obtained by encrypting the random value z by applying the hash value H (d) and the hash value H (d) It is possible to prevent a security problem that may occur according to the present invention, thereby further enhancing security of data.

In addition, the transmitting apparatus 100 according to the embodiment of the present invention includes the encryption function E used in steps S107 and S111, the hash function H used in step S109, the key derivation function KDF used in step S105, Is set in advance in advance as shown in <Table 1> described above. Then, the transmitting apparatus 100 of the present invention selects and sets any one of a plurality of sets composed of an encryption function E, a hash function H, and a key derivation function KDF, The encryption process E1, the hash function H3, and the key derivation function KDF1 are performed. Here, the set of functions for encryption must be shared with the receiving apparatus 200 in advance, and the same set of functions must be set in advance between the transmitting apparatus 100 and the receiving apparatus 200.

Hereinafter, a decoding method in the receiving apparatus 200 according to the embodiment of the present invention will be described.

7 is a flowchart illustrating a decoding method in a receiving apparatus according to an embodiment of the present invention.

4 and 7, the receiving unit 210 of the receiving apparatus 200 according to the embodiment of the present invention receives the scrambled data C transmitted by the transmitting apparatus 100, that is, the encrypted data E (d ) E (H (d)) obtained by encrypting the random value z by applying the hash value H (d) applied with the data d to the hash function H and the hash value _H (z)) (S201).

The descrambling unit 220 of the receiving apparatus 200 of the present invention performs descrambling to restore the received data to its original arrangement according to a predetermined scramble pattern previously shared with the transmitting apparatus 100 (S203).

The hash value H (d) and the hash value H (d), which are obtained by applying the decrypted data E (d), the data d to the hash function H, a value encrypted random value (z) by applying a key (E _H (z)) is therefore restored to its original place, the group of encrypted data from the arrangement set (E (d)), the hash function to the data (d) ( a hash value (H (d)) and the hash value (H (d)) (a value (E _H (z encrypt z))) random value by applying the encryption key is applied to H) can be extracted respectively.

In addition, since the receiving apparatus 200 of the present invention does not know the encryption key used for encryption in the transmitting apparatus 100, the transmitting apparatus 100 first performs a process of generating an encryption key used for encryption in the transmitting apparatus 100 do.

To this end, the receiving apparatus 200 of the present invention extracts a hash value H (d) obtained by applying the data d from the descrambled data to the hash function H through the decryption processing unit 230 (S205 ). The decryption processing unit 230 of the receiving apparatus 200 of the present invention applies the hash value H (d) extracted from the descrambled data with the extracted hash value H (d) to the random value z, (E _H (z)) by decrypting the random value z (S207).

The decryption processing unit 230 of the receiving apparatus 200 of the present invention applies the extracted random value z to the key derivation function to generate an encryption key (S209). Here, the process of generating the encryption key is performed in the same manner as in step S105 of FIG.

The decryption processing unit 230 of the receiving apparatus 200 of the present invention can decrypt the encrypted data E (d) confirmed by descrambling in step S203 using the generated encryption key (S211) . Accordingly, even if the encryption key is not transmitted or received, the original data to be transmitted by the transmission apparatus 100 can be confirmed.

The decryption processing unit 230 of the receiving apparatus 200 of the present invention performs the verification procedure using the hash value H (d) generated by applying the data d to the predetermined hash function H S213). In other words, the hash value H (d) is generated by applying the confirmed data d to the predetermined hash function H to generate the hash value H (d) 100), and verifies whether or not the decryption processing has been normally performed by comparing the hash value H (d).

If the data to be transmitted by the transmitting apparatus 100 is confirmed through the above process, the receiving apparatus 200 of the present invention can process the data (S215). For example, it can carry out a specific function according to the confirmed data or transmit it to a device for performing a function.

As described above, according to the encryption and decryption method according to the embodiment of the present invention, data is encrypted through an encryption key generated based on a random value rather than a public key, thereby solving the security problem due to the exposure of the encryption key .

In addition, according to the present invention, not only the data to be encrypted but also all the values generated in the encryption process are scrambled and transmitted to the receiving apparatus, so that a security problem that may be caused by data transmission and reception can be prevented, It can be done more efficiently.

The encryption and decryption method according to the embodiment of the present invention has been described above.

The encryption and decryption method of the present invention as described above may be provided in the form of a computer readable medium suitable for storing computer program instructions and data. A program recorded on a recording medium for implementing an encryption method according to an embodiment of the present invention includes the steps of receiving data d, applying an encryption function E to the input data d, , Encrypting the encrypted data E (d) and the data generated in the encrypting step, and transmitting the scrambled data.

According to another aspect of the present invention, there is provided a program recorded on a recording medium for implementing a decoding method, comprising: receiving scrambled data; descrambling the scrambled data; Decrypting the encrypted data (E (d)) from the descrambled data using the generated encryption key, and decrypting the decrypted data (d) using the generated encryption key Verification step, and the like.

At this time, the program recorded on the recording medium can be read and installed in the computer and executed, thereby executing the above-described functions.

In order to allow a computer to read a program recorded on a recording medium and to execute functions implemented by the program, the above-mentioned program may be stored in a computer-readable medium such as C, C ++, JAVA, machine language, and the like.

The code may include a function code related to a function or the like that defines the functions described above and may include an execution procedure related control code necessary for the processor of the computer to execute the functions described above according to a predetermined procedure. In addition, such code may further include memory reference related code as to what additional information or media needed to cause the processor of the computer to execute the aforementioned functions should be referenced at any location (address) of the internal or external memory of the computer . In addition, when a processor of a computer needs to communicate with any other computer or server that is remote to execute the above-described functions, the code may be stored in a memory of the computer using a communication module of the computer, It may further include a communication-related code such as how to communicate with another computer or a server, and what information or media should be transmitted or received during communication.

Such computer-readable media suitable for storing computer program instructions and data include, for example, magnetic media such as hard disks, floppy disks and magnetic tape, compact disk read only memory (CD-ROM) Optical media such as a DVD (Digital Video Disk), a magneto-optical medium such as a floppy disk, and a ROM (Read Only Memory), a RAM , Random Access Memory), flash memory, EPROM (Erasable Programmable ROM), and EEPROM (Electrically Erasable Programmable ROM). The processor and memory may be supplemented by, or incorporated in, special purpose logic circuits.

The computer readable recording medium may also be distributed over a networked computer system so that computer readable code can be stored and executed in a distributed manner. The functional program for implementing the present invention and the related code and code segment may be implemented by programmers in the technical field of the present invention in consideration of the system environment of the computer that reads the recording medium and executes the program, Or may be easily modified or modified by the user.

While the specification contains a number of specific implementation details, it should be understood that they are not to be construed as limitations on the scope of any invention or claim, but rather on the description of features that may be specific to a particular embodiment of a particular invention Should be understood. Certain features described herein in the context of separate embodiments may be implemented in combination in a single embodiment. Conversely, various features described in the context of a single embodiment may also be implemented in multiple embodiments, either individually or in any suitable subcombination. Further, although the features may operate in a particular combination and may be initially described as so claimed, one or more features from the claimed combination may in some cases be excluded from the combination, Or a variant of a subcombination.

Likewise, although the operations are depicted in the drawings in a particular order, it should be understood that such operations must be performed in that particular order or sequential order shown to achieve the desired result, or that all illustrated operations should be performed. In certain cases, multitasking and parallel processing may be advantageous. Also, the separation of the various system components of the above-described embodiments should not be understood as requiring such separation in all embodiments, and the described program components and systems will generally be integrated together into a single software product or packaged into multiple software products It should be understood.

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an encryption method, and more particularly, to an encryption method capable of decrypting data without sharing an encryption key used for data encryption, and a transmitting apparatus, a decrypting method, and a receiving apparatus using the same.

According to the present invention, not only the data to be encrypted but also all the values generated in the encryption process are scrambled and transmitted to the receiving device, thereby preventing a security problem that may be caused by data transmission and reception. Can contribute to the development of the security service industry.

In addition, since the present invention is not only possible to be marketed or operated, but also can be practically and practically carried out, it is industrially applicable.

100: transmitting apparatus 110: data input unit
120: Encryption processing unit 130: Scrambling unit
140: Transmission unit 150: Transmission storage unit
200: receiving apparatus 210: receiving section
220: descrambling unit 230: decryption processing unit
240: Data processing unit 250:
300: Encryption system

Claims (13)

An encryption method in a transmitting apparatus including a plurality of sets including an encryption function (E), a hash function (H), and a key derivation function (KDF)
When the transmitting apparatus
Receiving data (d);
Generating an encryption key by applying an arbitrary random value (z) to a key derivation function (KDF) of any one of the plurality of sets;
Encrypting the data (d) using the encryption function (E) constituting any one of the sets and the generated encryption key, and applying a hash function (H) constituting any one of the sets to the data (d) Generating a hash value H (d) and encrypting the random value z using the hash value H (d) and the encryption function E;
Scrambling a value E _H (z) obtained by encrypting the encrypted data E (d), the hash value H (d) for the data d, and the random value z; And
Transmitting the scrambled value to a receiving device;
And encrypting the encrypted data. delete delete delete delete The method according to claim 1,
Sharing the plurality of sets with the receiving apparatus;
Further comprising the step of: A transmission apparatus comprising a plurality of sets including an encryption function (E), a hash function (H), and a key derivation function (KDF)
The transmitting apparatus
A data input unit for receiving data d to be encrypted;
Generating an encryption key by applying an arbitrary random value z to a key derivation function KDF of any one of the plurality of sets and generating an encryption function E Encrypts the data d using the generated encryption key and applies a hash function H constituting any one of the sets to the data d to generate a hash value H An encryption processing unit for encrypting the random value z using the hash value H (d) and the encryption function E;
A scrambling unit for scrambling a value E _H (z) obtained by encrypting the encrypted data E (d), the hash value H (d) for the data d, and the random value z; And
A transmitter for transmitting the scrambled value to a receiver;
And the encryption method is used. Receiving data (d);
(Z) to a key derivation function (KDF) of any one of a plurality of sets including an encryption function (E), a hash function (H) and a key derivation function (KDF) Generating an encryption key;
(D) by using a cryptographic function (E) constituting a set and a generated encryption key, and applying a hash function (H) constituting any one of the sets to the data (d) Generating a hash value H (d) and encrypting the random value z using the hash value H (d) and the encryption function E; And
Scrambling a value E _H (z) obtained by encrypting the pre-encrypted data E (d), the hash value H (d) for the data d, and the random value z;
And encrypting the encrypted data with the encryption key. A decoding method in a receiving apparatus including a plurality of sets including an encryption function (E), a hash function (H), and a key derivation function (KDF)
The receiving device
Receiving scrambled data from a transmitting device;
Descrambling the scrambled data;
Extracting a hash value H (d) of the data d from the descrambled data and verifying the random value z using a hash value H (d) of the data d, Generating an encryption key by applying the identified random value z to a set of key derivation functions (KDF) of the plurality of sets;
Decrypting the encrypted data E (d) in the descrambled data using the generated encryption key; And
Generating the hash value H (d) by applying the data d to the set of hash functions H and generating the hash value H (d) Comparing the hash value H (d) of the received data d with the hash value H (d);
And decrypting the decrypted data. delete delete A receiving unit for receiving scrambled data from a transmitting apparatus;
A descrambling unit for descrambling the scrambled data; And
(D) of the data d from the descrambled data by using a hash value H (d) of the data d, and outputs the random value z as a hash value H (d) And generating an encryption key by applying the identified random value z to a set of key derivation functions (KDF) of a plurality of sets, and using the generated encryption key, Decrypting the encrypted data E (d) from the descrambled data and applying the data d to the set of hash functions H to generate a hash value H (d) A decoding processor for comparing and verifying the generated hash value H (d) with a hash value H (d) of the data d extracted from the descrambled data;
And decodes the received signal. Receiving scrambled data;
Descrambling the scrambled data;
Extracts a hash value H (d) of the data d from the scrambled data and confirms the random value z by using a hash value H (d) of the data d, The identified random value z is applied to a set of key derivation functions (KDF) of a plurality of sets including a cryptographic function E, a hash function H and a key derivation function KDF Generating an encryption key;
Decrypting the encrypted data E (d) in the descrambled data using the generated encryption key; And
Generating a hash value H (d) by applying the hash value H (d) to the set of hash functions H to generate a hash value H Comparing the hash value H (d) of the received data d with the hash value H (d);
And a decryption step of decrypting the decrypted encrypted data.

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