KR20230092233A - Did-based signature method and system using bbs+ signature - Google Patents

Abstract

The present invention relates to a DID-based signature method using a BBS+ signature. The DID-based signature method using a BBS+ signature comprises: a step in which an owner system provides a common value for a BBS+ signature to an issuer system; a step in which the issuer system generates a first BBS+ signature associated with the issuer system using the provided common value; a step in which the owner system transmits a DID-based VC issuance request to the issuer system; a step in which the issuer system creates a VC associated with the owner system in response to the issuance request; a step in which the issuer system associates the first BBS+ signature with the created VC; and a step in which the issuer system provides the VC associated with the first BBS+ signature to the owner system. According to the present invention, VP creation and signature verification can be effectively simplified.

Description

DID-based signature method and system using BBS+ signature {DID-BASED SIGNATURE METHOD AND SYSTEM USING BBS+ SIGNATURE}

The present invention relates to a DID-based signature method and system using BBS+ signatures, and more specifically, to a DID-based signature method and system using BBS+ signatures that perform zero-knowledge proofs, set signatures, etc. through BBS+ signatures.

Decentralized identifiers (DIDs) may represent an electronic identification system built on the basis of blockchain technology or an identifier used in the system. For example, when using DID, a user can distribute and store identity information on personal devices such as smartphones and tablets rather than on a central server, thereby directly managing the ownership of their identity.

In general, when such a DID is used, various signature and verification technologies may be used to verify whether the issuer is legitimately issued and to prove the owner's identity. However, if the signature is repeatedly performed for each verifiable credential whenever identity verification is required, the time required for signing and verification may significantly increase. In addition, when the verification is completed, the identity information may be disclosed to the verifier, and thus there is a risk of leakage of the identity information.

The present invention provides a DID-based signature method using a BBS+ signature, a computer program stored in a computer readable medium, a computer readable medium and a system (device) in which the computer program is stored to solve the above problems.

The present invention can be implemented in a variety of ways, including methods, systems (devices), computer programs stored on computer readable media or computer readable media on which computer programs are stored.

According to an embodiment of the present invention, a DID-based signature method using a BBS+ signature includes steps in which an owner system provides a common value for a BBS+ signature to an issuer system; Generating a first BBS+ signature, the owner system sending a DID-based VC issuance request to the issuer system, in response to receiving the issuance request, the issuer system creating a VC associated with the owner system, the issuer system associating this first BBS+ signature with the created VC and the issuer system providing the VC associated with the first BBS+ signature to the owner system.

According to one embodiment of the present invention, in response to the owner system receiving the VC associated with the first BBS+ signature, obtaining a public key associated with the issuer system from a blockchain network and the owner system publishing the obtained issuer system associated public key. and performing signature verification on the first BBS+ signature using the key.

According to one embodiment of the present invention, the steps of the verifier system sending a VP submission request to the owner system, the owner system generating a second BBS+ signature associated with the owner system, and the owner system generating each claim included in the VC. determining whether to publish the VP associated with the owner system, the owner system associating the second BBS+ signature with the generated VP, and the owner system providing the VP associated with the second BBS+ signature to the verifier system. more includes

According to one embodiment of the present invention, obtaining a public key associated with an owner system and a public key associated with an issuer system from a blockchain network in response to the verifier system receiving the VP associated with the second BBS+ signature and the verifier Further comprising the system performing signature verification on the first BBS+ signature and the second BBS+ signature using the obtained public key associated with the owner system and the public key associated with the issuer system.

According to one embodiment of the present invention, the VC includes a plurality of VCs. The step of determining, by the owner system, whether to disclose each claim included in the VC and creating a VP associated with the owner system, wherein the owner system combines the plurality of VCs and determines whether each claim included in the plurality of VCs is disclosed. determining and creating a VP associated with the owner system.

According to one embodiment of the present invention, further comprising the owner system sending a nonce value request to a verifier system, and in response to receiving the nonce value request, the verifier system generating a nonce value. The step of the verifier system sending the VP submission request to the owner system includes the verifier system sending the VP submission request including the generated nonce value to the owner system.

A computer program stored in a computer readable recording medium is provided to execute the above-described method according to an embodiment of the present invention on a computer.

A DID-based signature system using a BBS+ signature according to an embodiment of the present invention includes at least one processor configured to execute at least one computer-readable program included in a memory. The at least one program causes the owner system to provide a common value for the BBS+ signature to the issuer system, the issuer system to use the provided common value to generate a first BBS+ signature associated with the issuer system, and the owner system to issue a DID to the issuer system. In response to sending the based VC issuance request and receiving the issuance request, the issuer system creates a VC associated with the owner system, the issuer system associates a first BBS+ signature with the created VC, and the issuer system associates the first BBS+ signature with the created VC. Contains instructions for providing the VC associated with the BBS+ signature to the owner system.

According to one embodiment of the present invention, at least one program obtains a public key associated with an issuer system from a blockchain network in response to the owner system receiving the VC associated with the first BBS+ signature, and the owner system obtains the VC associated with the first BBS+ signature. Further comprising instructions for performing signature verification on the first BBS+ signature using the public key associated with the issuer system.

According to one embodiment of the invention, at least one program causes the verifier system to send a VP submission request to the owner system, the owner system to generate a second BBS+ signature associated with the owner system, and the owner system to include in the VC. determine whether to disclose each claimed claim, create a VP associated with the owner system, the owner system associates a second BBS+ signature with the generated VP, and the owner system provides the VP associated with the second BBS+ signature to the verifier system It contains more commands to do this.

According to one embodiment of the present invention, at least one program, in response to the verifier system receiving the VP associated with the second BBS+ signature, obtains from the blockchain network a public key associated with the owner system and a public key associated with the issuer system. obtain and cause the verifier system to perform signature verification on the first BBS+ signature and the second BBS+ signature using the obtained public key associated with the owner system and the public key associated with the issuer system.

According to one embodiment of the present invention, the VC includes a plurality of VCs. The at least one program further includes instructions for causing the owner system to combine the plurality of VCs, determine whether to disclose each claim included in the plurality of VCs, and create a VP associated with the owner system.

According to one embodiment of the present invention, the at least one program sends a request for a nonce value from an owner system to a verifier system, and in response to receiving the request for a nonce value, the verifier system generates and verifies a nonce value. It further includes instructions for causing the child system to send a VP submit request containing the generated nonce value to the owner system.

In various embodiments of the present invention, by additionally using the BBS+ signature, unlike the existing VC provision method, set signature, zero-knowledge proof, etc. can be performed faster and more efficiently than other signature methods.

In various embodiments of the present invention, the owner system generates an integrated VP by selecting only necessary information from claims included in a plurality of VCs and performs BBS+ signature, thereby effectively simplifying the process of VP generation and signature verification.

In various embodiments of the present invention, verification of a DID document associated with an arbitrary system can be simply performed through encryption and decryption of a nonce value.

The effects of the present invention are not limited to the effects mentioned above, and other effects not mentioned are clear to those skilled in the art (referred to as "ordinary technicians") from the description of the claims. will be understandable.

BRIEF DESCRIPTION OF THE DRAWINGS Embodiments of the present invention will be described with reference to the accompanying drawings described below, wherein like reference numbers indicate like elements, but are not limited thereto.
1 is a diagram illustrating an example in which an issuer system, an owner system, and a verifier system perform a DID-based signature using a BBS+ signature according to an embodiment of the present invention.
2 is a diagram illustrating an example in which an integrated VP is provided according to an embodiment of the present invention.
3 is an exemplary flowchart illustrating a process in which DID verification is performed between an issuer system, an owner system, a verifier system, and a blockchain network according to an embodiment of the present invention.
4 is an exemplary flowchart illustrating a process in which VC issuance and BBS+ signature verification are performed between an issuer system, an owner system, a verifier system, and a blockchain network according to an embodiment of the present invention.
5 is an exemplary flow diagram illustrating a process in which VP creation and BBS+ signature verification are performed between an owner system, a verifier system, and a blockchain network according to an embodiment of the present invention.
6 is an exemplary flow diagram illustrating a process in which integrated VP creation and BBS+ signature verification are performed between an owner system, a verifier system, and a blockchain network according to an embodiment of the present invention.
7 is a flowchart illustrating an example of a DID-based signature method using a BBS+ signature according to an embodiment of the present invention.
8 is a flowchart illustrating an example of a method for generating and verifying a VP using a BBS+ signature according to an embodiment of the present invention.

Hereinafter, specific details for the implementation of the present invention will be described in detail with reference to the accompanying drawings. However, in the following description, if there is a risk of unnecessarily obscuring the gist of the present invention, detailed descriptions of well-known functions or configurations will be omitted.

In the accompanying drawings, identical or corresponding elements are given the same reference numerals. In addition, in the description of the following embodiments, overlapping descriptions of the same or corresponding components may be omitted. However, omission of a description of a component does not intend that such a component is not included in an embodiment.

Advantages and features of the disclosed embodiments, and methods of achieving them, will become apparent with reference to the following embodiments in conjunction with the accompanying drawings. However, the present invention is not limited to the embodiments disclosed below and can be implemented in various different forms, only these embodiments make the present invention complete and the scope of the invention to those skilled in the art. It is provided only for complete information.

Terms used in this specification will be briefly described, and the disclosed embodiments will be described in detail. The terms used in this specification have been selected from general terms that are currently widely used as much as possible while considering the functions in the present invention, but these may vary depending on the intention or precedent of a person skilled in the related field, the emergence of new technologies, and the like. In addition, in a specific case, there is also a term arbitrarily selected by the applicant, and in this case, the meaning will be described in detail in the description of the invention. Therefore, the term used in the present invention should be defined based on the meaning of the term and the overall content of the present invention, not simply the name of the term.

Expressions in the singular number in this specification include plural expressions unless the context clearly dictates that they are singular. Also, plural expressions include singular expressions unless the context clearly specifies that they are plural. When it is said that a certain part includes a certain component in the entire specification, this means that it may further include other components without excluding other components unless otherwise stated.

In the present invention, the terms "comprise", "comprising" and the like may indicate that features, steps, operations, elements and/or components are present, but may be used when such terms include one or more other functions, It is not excluded that steps, actions, elements, components, and/or combinations thereof may be added.

In the present invention, when a specific element is referred to as being “coupled”, “combined”, “connected”, or “reactive” to any other element, the specific element is directly bonded to, combined with, and/or other elements. or may be linked or reacted, but is not limited thereto. For example, one or more intermediate components may exist between certain components and other components. Also, in the present invention, “and/or” may include each of one or more items listed or a combination of at least a part of one or more items.

In the present invention, terms such as "first" and "second" are used to distinguish a specific component from other components, and the aforementioned components are not limited by these terms. For example, the “first” element may have the same or similar shape as the “second” element.

In the present invention, a "BBS+ signature" may be a digital signature that supports multiple message signatures to create a single signature. That is, when using the BBS+ signature, one additional signature can be generated for multiple pre-signed messages, and when using the signature generated in this way, the identity information by verification can be proven without being disclosed, so zero-knowledge proof (ZKP, Zero-Knowledge Proof) may be performed.

In the present invention, “Verifiable Credential (VC)” may refer to a set of data and/or information representing evidence of identity or qualification, and may be a set of verifiable data issued by an issuer system. . In addition, claims included in the VC may refer to evidence of each identity or qualification included in the data set, for example, in the case of a resident registration card, an individual's name, resident registration number, address, etc. are included in the VC may be each claim.

In the present invention, "Verifiable Presentation (VP)" is a set of data and/or information that a holder system provides to a verifier system to prove its identity or qualifications, which is the issuer system. may be a set of data created by and provably owned by the owner system.

In the present invention, "DID (Decentralized Identifier)" is a global unique identifier that does not require a registrar such as a centralized server by registering in a distributed storage using distributed ledger technology or other distributed network technology. can refer to

In the present invention, the "issuer system" may be a system of an institution that issues a verifiable credential (VC) for a specific user, and the "verifier system" verifies the owner's identity through a verifiable presentation (VP). It may be a system of an institution that provides a specific service to a verified owner after verification. Also, the "owner system" may be an owner's system that directly manages its own identity. The issuer system, owner system and/or verifier system may further have public and private keys associated with the DID as well as public and private keys associated with the BBS+ signature.

1 is a diagram illustrating an example in which the issuer system 110, the owner system 120, and the verifier system 130 perform a DID-based signature using a BBS+ signature according to an embodiment of the present invention. According to an embodiment, a decentralized identifier (DID) may refer to a technique of distributing and managing personal information to individual user terminals (eg, smart phones, tablets, etc.) rather than a central server. As shown, the issuer system 110, the owner system 120, and the verifier system 130 communicate with each other and can send and receive data and/or information necessary to perform DID-based signing using BBS+ signatures. .

In general, for use of DID, owner system 120 may send a DID-based VC issuance request to issuer system 110 . In this case, in response to receiving the issue request, the issuer system 110 may create a VC associated with the owner system 120 and issue the VC to the owner system 120 . Here, VC may include information about the DID of the owner system 120. Then, when the identity of the owner associated with the owner system 120 is required, the verifier system 130 transmits a VP submission request to the owner system 120 and obtains the VP associated with the owner system 120. can In this case, the verifier system 130 may verify the identity of the owner associated with the owner system 120 by performing verification on the obtained VP.

According to an embodiment, when generating and issuing a VC, the issuer system 110 may sign the issuance of the VC with a private key of the issuer system 110 and store it in the storage 140 (eg, a blockchain network). . In this case, the issuer system 110 may store the corresponding private key and the public key constituting the key pair in the storage 140 . Then, when verification of the VC issuance is performed, the verifier system 130 etc. decrypts the VC issuance fact using the public key of the issuer system 110 stored in the storage 140, so that the corresponding VC The issuer system 110 may determine whether or not it has been legitimately issued.

According to one embodiment, when generating and providing a VP, the owner system 120 may sign the VP with a private key of the owner system 120 and provide it to the verifier system 130 . In this case, the owner system 120 may store the corresponding private key and the public key constituting the key pair in the storage 140 . Then, when verifying the VP, the verifier system 130 uses the public key of the owner system 120 stored in the storage 140 to decrypt the corresponding VP, and thus the owner system 120 associated with the corresponding VP. ) is the rightful owner.

According to one embodiment, a BBS+ signature may additionally be used in the general identity verification process described above. For example, when signature verification is performed in the above-described identity verification process, the entire signature and contents associated with the message may be disclosed. However, when BBS+ signature is additionally used, zero-knowledge proof that proves integrity without disclosing the transmitted message (content) can be quickly and simply performed. That is, when using BBS+ signatures, the owner can selectively publish each of the signed messages.

,

)을 제공할 수 있다. 이 경우, 소유자 시스템(120)은 제공된 공통 값을 이용하여 BBS+ 서명을 생성하고, 생성된 BBS+ 서명을 VC와 연관시킬 수 있다. 예를 들어, BBS+ 서명은 페어링하기 쉬운(paring-friendly) 타원 곡선을 사용하여 생성될 수 있다. BBS+ 서명을 위해, 동일한 소수 p의 순환 그룹

과

가 정의될 수 있으며, 공통 값은

및

로부터 획득된 값일 수 있다. 또한,

및

로부터 결정되는 쌍선형 맵(bilinear map)이 다음의 수학식 1과 같이 정의될 수 있다.According to one embodiment, owner system 120 communicates with issuer system 110 a common value for BBS+ signatures (e.g.,

,

) can be provided. In this case, the owner system 120 may use the provided common value to generate a BBS+ signature and associate the generated BBS+ signature with the VC. For example, BBS+ signatures can be created using paring-friendly elliptic curves. For BBS+ signatures, cyclic groups of equal prime p

class

can be defined, and common values are

and

It may be a value obtained from also,

and

A bilinear map determined from may be defined as in Equation 1 below.

는 동일한 소수 P의 또 다른 순환 그룹이며, e는 쌍선형 맵일 수 있다. 이러한 쌍선형 맵은 다항식 시간 계산이 가능한 맵일 수 있으며, 다음의 수학식 2에 의해 요소 값

를 생성할 수 있다.here,

is another cyclic group of the same prime P, and e can be a bilinear map. Such a bilinear map may be a map capable of polynomial time calculation, and element values are obtained by Equation 2 below.

can create

,

및

는 각각 순환 그룹

,

및

에 의해 정의된 값일 수 있다.here,

,

and

are each cyclic group

,

and

It can be a value defined by

가 주어졌을 때, BBS+ 서명은

와 같이 L+2 개의 변수를 갖는 키(예: 공개키)를 생성할 수 있다. 구체적으로, 다음의 수학식 3과 같이 순환 그룹

으로부터 L+1 개의 랜덤 값이 생성될 수 있다.According to one embodiment, a key may be generated for BBS+ signing. For example, L messages

Given that, the BBS+ signature is

A key (e.g., public key) having L+2 variables can be generated. Specifically, as shown in Equation 3 below, the cyclic group

L+1 random values may be generated from

In this case, the private key (x) for the BBS+ signature may be determined as a random value as in Equation 4 below, and the w value for generating the public key may be calculated as in Equation 5 below.

)은 다음의 수학식 6과 같이 정의될 수 있다.As described above, after the public and private keys for the BBS+ signature are generated, the BBS+ signature can be generated. For example, the BBS+ signature (

) may be defined as in Equation 6 below.

Here, e and s are random values and can be generated by Equation 7 below, and the value A can be calculated by Equation 8 below.

According to one embodiment, issuer system 110 may generate a VC and then associate the BBS+ signature generated as described above with the corresponding VC and provide it to owner system 120, and owner system 120 may provide the BBS+ signature. Various services can be provided using VC related to .

In FIG. 1 , it is shown that one issuer system 110 and one verifier system 130 exist, but it is not limited thereto, and a plurality of issuer systems and/or a plurality of verifier systems may exist. With this configuration, unlike the existing VC provision method, by additionally using the BBS+ signature, set signature, zero-knowledge proof, etc. can be performed faster and more efficiently than other signature methods.

2 is a diagram illustrating an example in which an integrated VP 230 is provided according to an embodiment of the present invention. As shown, the owner system 120 may receive the first VC 210 from the first issuer system 110_1 and the second VC 220 from the second issuer system 110_2. As described above, owner system 120 provides common values for BBS+ signatures to first issuer system 110_1 and second issuer system 110_2, and first VC 210 and 210 associated with each BBS+ signature. A second VC 220 may be provided.

According to one embodiment, the owner system 120 combines at least some of the claims included in the first VC 210 and at least some of the claims included in the second VC 220 to create an integrated VP 230. can That is, the owner system 120 may generate the integrated VP 230 by selecting only information necessary for using a specific service from the plurality of VCs 210 and 220 . In this case, the owner system 120 may provide the created unified VP 230 to the verifier system 130 to prove its identity and use the specific service associated with the verifier system 130 .

According to one embodiment, owner system 120 may generate a BBS+ signature associated with the owner system. For example, owner system 120 may generate a BBS+ signature using the equations discussed above in FIG. 1 or the like. Additionally, the owner system 120 may combine the generated BBS+ signature with the aggregating VP 230 and provide it to the verifier system 130 . Here, consolidated VP 230 may include a BBS+ signature associated with issuer system 110 (e.g., a first BBS+ signature) and a BBS+ signature associated with owner system 120 (e.g., a second BBS+ signature).

According to one embodiment, the verifier system 130 may perform signature verification for the unified VP 230 . For example, verifier system 130 may perform signature verification for a first BBS+ signature using a public key associated with issuer system 110 (the public key associated with the first BBS+ signature). . Additionally, verifier system 130 may perform signature verification on the second BBS+ signature using the public key associated with owner system 120 (the public key associated with the second BBS+ signature). Signature verification may be performed by Equation 9 below.

For example, signature verification may be performed based on whether the left and right sides of Equation 9 are the same. That is, when the left side and the right side of Equation 9 are the same for each BBS+ signature, it can be determined that each BBS+ signature is verified. In this way, when identity verification is completed through signature verification, the owner system 120 may use a service associated with the verifier system 130 .

In FIG. 2, the owner system 120 is shown as combining at least a portion of the two VCs 210 and 220 to create an integrated VP 230, but is not limited thereto. Corresponding VPs may be separately generated and provided to the verifier system 130 . In addition, although it is shown that there are two issuer systems 110_1 and 110_2 in FIG. 2, the present invention is not limited thereto, and any number of issuer systems may exist. With this configuration, the owner system 120 selects only necessary information from among the claims included in the plurality of VCs 210 and 220 to generate the integrated VP 230 and performs the BBS+ signature, thereby generating the VP and verifying the signature. can be effectively simplified.

3 is an exemplary flow diagram illustrating a process in which DID verification is performed between the issuer system 110, the owner system 120, the verifier system 130 and the blockchain network 140 according to an embodiment of the present invention. . As shown, the issuer system 110, the owner system 120, the verifier system 130, and the blockchain network 140 may exchange data and/or information necessary for DID verification.

According to one embodiment, the issuer system 110 may generate a key pair associated with the issuer system 110 (a public key and a private key associated with the DID) and a DID (312). Owner system 120 may also generate a key pair and DID associated with owner system 120 ( 314 ). Similarly, verifier system 130 may generate a key pair and DID associated with verifier system 130 (316).

DID documents associated with the DID created in this way may be stored and managed in the blockchain network 140 (318). Here, the DID document may be a document including information about a public key related to the DID, standards for using the DID, and the like. DID exchange and verification may then be performed using the DID documents stored on the blockchain network 140 (322, 324). For example, when the owner system 120 obtains the DID of the issuer system 110, the DID document associated with the corresponding DID is extracted from the blockchain network 140 and then decrypted using a public key to verify the DID. can be performed.

According to one embodiment, the owner system 120 or the like performing the DID verification may receive the DID from the issuer system 110 and/or the verifier system 130 . In this case, the owner system 120 may request and obtain a DID document corresponding to the corresponding DID from the blockchain network 140 using the provided DID. Owner system 120 may then generate an arbitrary nonce value based on the obtained DID document. Here, the nonce value may be any random value associated with the DID document. The owner system 120 encrypts the generated nonce value based on an arbitrary algorithm and transfers it to the issuer system 110 and/or the verifier system 130, and the issuer system 110 and/or the verifier system A decrypted nonce value may be delivered from (130). In this case, the owner system 120 may complete verification of the DID document by comparing the received decrypted nonce value with the nonce value generated by the owner system 120 .

In FIG. 3 , it is detailed that the owner system 120 verifies the DID document of the issuer system 110 and/or the verifier system 130 , but is not limited thereto. For example, the issuer system 110 and/or the verifier system 130 may perform DID document verification of other systems through the same process as described above. With this configuration, verification of a DID document associated with an arbitrary system can be easily performed through encryption and decryption of a nonce value.

4 shows a process in which VC issuance and BBS+ signature verification are performed between the issuer system 110, the owner system 120, the verifier system 130 and the blockchain network 140 according to an embodiment of the present invention. It is an exemplary flow chart. As shown, issuer system 110, owner system 120, verifier system 130, and blockchain network 140 may send and receive data and/or information necessary for VC issuance and BBS+ signature verification.

According to one embodiment, owner system 120 may provide common values 412 and 414 for BBS+ signatures to issuer system 110 and/or verifier system 130 . In addition, the owner system 120 may transmit a DID-based VC issuance request 416 to the issuer system 110 . In this case, the issuer system 110 may use the provided common value 412 to generate a first BBS+ signature associated with the issuer system 110 and a VC associated with the owner system 120 (418). For example, a first BBS key pair may be generated based on the common value 412, and a first BBS+ signature may be generated based on the first BBS key pair. Additionally, issuer system 110 may associate the first BBS+ signature with the created VC. The issuer system 110 may then store the public key 422 associated with the first BBS+ signature on the blockchain network 140 .

According to one embodiment, issuer system 110 may provide VC and public key storage address 424 to owner system 120 . Here, the VC may be signed with the private key of the issuer system 110 and provided to the owner system 120 . In this case, the owner system 120 may perform VC signature verification using the public key associated with the issuer system 110 (426). For example, owner system 120 may perform VC signature verification using the public key of issuer system 110 included in the provided VC.

According to one embodiment, owner system 120 may obtain public key 428 associated with the first BBS+ signature from blockchain network 140 . Owner system 120 may then use the obtained public key 428 to perform a first BBS+ signature verification associated with VC (432). In this case, BBS+ signature verification may be performed by the same process as described above in FIG. 1 .

5 is an exemplary flow diagram illustrating a process in which VP creation and BBS+ signature verification are performed between the owner system 120, the verifier system 130, and the blockchain network 140 according to one embodiment of the present invention. As shown, owner system 120, verifier system 130, and blockchain network 140 may send and receive data and/or information necessary for VP creation and BBS+ signature verification.

According to one embodiment, owner system 120 may send a nonce value request 512 to verifier system 130 . In response to receiving nonce value request 512 , verifier system 130 may generate a nonce value. The verifier system 130 may then send a VP submission request 514 containing the generated nonce value to the owner system 120 . Here, the nonce value may be a random value calculated by an arbitrary algorithm.

Upon receiving VP Submit Request 514, owner system 120 may use the nonce value, common value, etc. included in VP Submit Request 514 to generate a second BBS+ signature and VP (516). For example, owner system 120 may create a VP associated with owner system 120 by determining whether to disclose each claim included in one or more VCs. That is, the owner system 120 may generate a VP by selecting only some of various identity information included in the VC. Owner system 120 can then associate the generated second BBS+ signature with the generated VP. In this case, the owner system 120 may store the public key 518 associated with the second BBS+ signature on the blockchain network 140 .

According to one embodiment, the owner system 130 may provide the verifier system 130 with the VP and public key storage address 522 associated with the second BBS+ signature. Here, the VP may be signed with the private key of the owner system 120 and provided to the verifier system 130. In this case, the verifier system 130 may perform VP signature verification using the public key associated with the owner system 120 (524). For example, verifier system 130 may perform VP signature verification using the public key of owner system 120 included in the provided VP.

According to one embodiment, verifier system 130 may obtain public key 526 associated with the second BBS+ signature from blockchain network 140 . Then, the verifier system 130 may perform a second BBS+ signature verification associated with the VP using the obtained public key 526 (528). Additionally, verifier system 130 may obtain from blockchain network 140 a public key associated with the first BBS+ signature (the BBS+ signature associated with the issuer system). Then, verifier system 130 may use the obtained public key to perform first BBS+ signature verification associated with the VP. In this case, BBS+ signature verification may be performed by the same process as described above in FIG. 1 .

6 is an exemplary flow diagram illustrating a process in which integrated VP creation and BBS+ signature verification are performed between the owner system 120, the verifier system 130, and the blockchain network 140 according to one embodiment of the present invention. As shown, the owner system 120, the verifier system 130, and the blockchain network 140 may send and receive data and/or information necessary for generating an aggregated VP and verifying the BBS+ signature.

Similar to what was described above in FIG. 5 , owner system 120 may send a nonce value request 612 to verifier system 130 . In response to receiving nonce value request 612 , verifier system 130 may generate a nonce value. The verifier system 130 may then send a VP submission request 614 containing the generated nonce value to the owner system 120 . Here, the nonce value may be a random value calculated by an arbitrary algorithm.

Upon receiving VP Submit Request 614, owner system 120 may use the nonce value, common values, etc. included in VP Submit Request 614 to generate 616 a second BBS+ signature and unified VP. . For example, owner system 120 may determine whether to disclose the plurality of VCs and each claim included in the plurality of VCs to create an aggregated VP associated with owner system 120 . That is, the owner system 120 may create an integrated VP by selecting only some of various identity information included in a plurality of VCs. Owner system 120 can then associate the generated second BBS+ signature with the created combined VP. In this case, the owner system 120 may store the public key 618 associated with the second BBS+ signature on the blockchain network 140 .

According to one embodiment, the owner system 130 may provide the verifier system 130 with the joint VP and public key storage address 622 associated with the second BBS+ signature. Here, the unified VP may be signed with the private key of the owner system 120 and provided to the verifier system 130 . In this case, the verifier system 130 may perform integrated VP signature verification using the public key associated with the owner system 120 (624). For example, the verifier system 130 may perform integrated VP signature verification using the public key of the owner system 120 included in the provided integrated VP.

According to one embodiment, verifier system 130 may obtain public key 626 associated with the second BBS+ signature from blockchain network 140 . Then, the verifier system 130 may use the obtained public key 626 to perform a second BBS+ signature verification associated with the unified VP (628). Additionally, verifier system 130 may obtain from blockchain network 140 a public key associated with the first BBS+ signature (the BBS+ signature associated with the issuer system). Then, verifier system 130 may use the obtained public key to perform first BBS+ signature verification associated with the combined VP. In this case, BBS+ signature verification may be performed by the same process as described above in FIG. 1 . With this configuration, when a plurality of VCs exist, one integrated VP can be created without creating a separate VP corresponding to each VC, and thus the efficiency of VP creation and signature is effectively reduced. can be increased

7 is a flowchart illustrating an example of a DID-based signature method 700 using a BBS+ signature according to an embodiment of the present invention. The DID-based signature method 700 using the BBS+ signature may be performed by at least one processor (eg, at least one processor of an issuer system, an owner system, and a verifier system). The DID-based signature method 700 using the BBS+ signature may be initiated by the owner system providing a common value for the BBS+ signature to the issuer system (S710). In this case, the issuer system may generate a first BBS+ signature associated with the issuer system using the provided common value (S720).

According to an embodiment, the owner system may transmit a DID-based VC issuance request to the issuer system (S730). In response to receiving the issue request, the issuer system may create a VC associated with the owner system (S740). For example, the created VC may include any identity information associated with the owner's system.

According to one embodiment, the issuer system may associate the first BBS+ signature with the generated VC (S750). In addition, the issuer system may provide the VC associated with the first BBS+ signature to the owner system (S760). In this case, the owner system obtains a public key associated with the issuer system from the blockchain network in response to receiving the VC associated with the first BBS+ signature, and uses the obtained public key associated with the issuer system to obtain information about the first BBS+ signature. You can perform signature verification.

8 is a flow diagram illustrating an example of a VP generation and verification method 800 using a BBS+ signature according to an embodiment of the present invention. The method 800 for generating and verifying a VP using a BBS+ signature may be performed by at least one processor (eg, at least one processor of an issuer system, an owner system, and a verifier system). The VP generation and verification method 800 using the BBS+ signature may be initiated by the verifier system sending a VP submission request to the owner system (S810). For example, the owner system could send a request for a nonce value to the verifier system. In this case, in response to receiving the nonce value request, the verifier system may generate a nonce value and send a VP submission request containing the generated nonce value to the owner system.

The owner system may generate a second BBS+ signature associated with the owner system (S820). In addition, the owner system may determine whether to disclose each claim included in the VC and create a VP associated with the owner system (S830). In this case, the owner system may combine a plurality of VCs, determine whether to disclose each claim included in the plurality of VCs, and create a VP associated with the owner system.

The owner system may associate the second BBS+ signature with the created VP (S840). Additionally, the owner system may provide the VP associated with the second BBS+ signature to the verifier system (S850). In this case, the verifier system may obtain the public key associated with the owner system and the public key associated with the issuer system from the blockchain network in response to receiving the VP associated with the second BBS+ signature. Then, the verifier system may perform signature verification for the first BBS+ signature and the second BBS+ signature using the obtained public key associated with the owner system and the public key associated with the issuer system.

The above-described methods and/or various embodiments may be realized with digital electronic circuits, computer hardware, firmware, software, and/or combinations thereof. Various embodiments of the present invention may be performed by a data processing device, eg, one or more programmable processors and/or one or more computing devices, or as a computer readable recording medium and/or a computer program stored on a computer readable recording medium. can be implemented The above-described computer programs may be written in any form of programming language, including compiled or interpreted languages, and may be distributed in any form, such as a stand-alone program, module, or subroutine. A computer program may be distributed over one computing device, multiple computing devices connected through the same network, and/or distributed over multiple computing devices connected through multiple different networks.

The methods and/or various embodiments described above may be performed by one or more processors configured to execute one or more computer programs that process, store, and/or manage any function, function, or the like, by operating on input data or generating output data. can be performed by For example, the method and/or various embodiments of the present invention may be performed by a special purpose logic circuit such as a Field Programmable Gate Array (FPGA) or an Application Specific Integrated Circuit (ASIC), and the method and/or various embodiments of the present invention may be performed. Apparatus and/or systems for performing the embodiments may be implemented as special purpose logic circuits such as FPGAs or ASICs.

The one or more processors executing the computer program may include a general purpose or special purpose microprocessor and/or one or more processors of any kind of digital computing device. The processor may receive instructions and/or data from each of the read-only memory and the random access memory, or receive instructions and/or data from the read-only memory and the random access memory. In the present invention, components of a computing device performing methods and/or embodiments may include one or more processors for executing instructions, and one or more memory devices for storing instructions and/or data.

According to one embodiment, a computing device may exchange data with one or more mass storage devices for storing data. For example, a computing device may receive/receive data from and transfer data to a magnetic or optical disc. A computer-readable storage medium suitable for storing instructions and/or data associated with a computer program includes semiconductor memory devices such as Erasable Programmable Read-Only Memory (EPROM), Electrically Erasable PROM (EEPROM), and flash memory devices. Any type of non-volatile memory may be included, but is not limited thereto. For example, computer readable storage media may include magnetic disks such as internal hard disks or removable disks, magneto-optical disks, CD-ROM and DVD-ROM disks.

To provide interaction with a user, a computing device includes a display device (eg, a cathode ray tube (CRT), a liquid crystal display (LCD), etc.) It may include a pointing device (eg, a keyboard, mouse, trackball, etc.) capable of providing input and/or commands to, but is not limited thereto. That is, the computing device may further include any other type of device for providing interaction with a user. For example, a computing device may provide any form of sensory feedback to a user for interaction with the user, including visual feedback, auditory feedback, and/or tactile feedback. In this regard, the user may provide input to the computing device through various gestures such as visual, voice, and motion.

In the present invention, various embodiments may be implemented in a computing system including a back-end component (eg, a data server), a middleware component (eg, an application server), and/or a front-end component. In this case, the components may be interconnected by any form or medium of digital data communication, such as a communication network. For example, the communication network may include a local area network (LAN), a wide area network (WAN), and the like.

A computing device based on the example embodiments described herein may be implemented using hardware and/or software configured to interact with a user, including a user device, user interface (UI) device, user terminal, or client device. can For example, the computing device may include a portable computing device such as a laptop computer. Additionally or alternatively, the computing device may include personal digital assistants (PDAs), tablet PCs, game consoles, wearable devices, internet of things (IoT) devices, virtual reality (VR) devices, AR (augmented reality) device, etc. may be included, but is not limited thereto. A computing device may further include other types of devices configured to interact with a user. Further, the computing device may include a portable communication device (eg, a mobile phone, smart phone, wireless cellular phone, etc.) suitable for wireless communication over a network, such as a mobile communication network. A computing device communicates wirelessly with a network server using wireless communication technologies and/or protocols such as radio frequency (RF), microwave frequency (MWF) and/or infrared ray frequency (IRF). It can be configured to communicate with.

The various embodiments herein, including specific structural and functional details, are exemplary. Accordingly, embodiments of the present invention are not limited to those described above and may be implemented in various other forms. In addition, terms used in the present invention are for describing some embodiments and are not construed as limiting the embodiments. For example, the singular and the above may be construed to include the plural as well, unless the context clearly dictates otherwise.

In the present invention, unless defined otherwise, all terms used in this specification, including technical or scientific terms, have the same meaning as commonly understood by a person of ordinary skill in the art to which such concept belongs. . In addition, terms commonly used, such as terms defined in a dictionary, should be interpreted as having a meaning consistent with the meaning in the context of the related technology.

Although the present invention has been described in relation to some embodiments in this specification, various modifications and changes can be made without departing from the scope of the present invention that can be understood by those skilled in the art. Moreover, such modifications and variations are intended to fall within the scope of the claims appended hereto.

110: issuer system
120: owner system
130: validator system
140: storage

Claims (13)

As a DID (Decentralized Identity) based signature method using BBS+ signature,
the holder system providing a common value for the BBS+ signature to the issuer system;
generating, by the issuer system, a first BBS+ signature associated with the issuer system using the provided common value;
transmitting, by the owner system, a request for issuing a DID-based Verifiable Credential (VC) to the issuer system;
in response to receiving the issuance request, the issuer system creating a VC associated with the owner system;
the issuer system associating the first BBS+ signature with the generated VC; and
the issuer system providing the owner system with a VC associated with the first BBS+ signature;
DID-based signature method using BBS + signature including.
According to claim 1,
obtaining a public key associated with the issuer system from a blockchain network in response to the owner system receiving the VC associated with the first BBS+ signature; and
the owner system performing signature verification on the first BBS+ signature using the obtained public key associated with the issuer system;
DID-based signature method using BBS + signature further comprising.
According to claim 2,
Transmitting, by a verifier system, a Verifiable Presentation (VP) submission request to the owner system;
generating, by the owner system, a second BBS+ signature associated with the owner system;
generating, by the owner system, a VP associated with the owner system by determining whether to disclose each claim included in the VC;
the owner system associating the second BBS+ signature with the created VP; and
the owner system providing the verifier system with a VP associated with the second BBS+ signature;
DID-based signature method using BBS + signature further comprising.
According to claim 3,
obtaining from a blockchain network a public key associated with the owner system and a public key associated with the issuer system in response to the verifier system receiving the VP associated with the second BBS+ signature; and
performing, by the verifier system, signature verification on the first BBS+ signature and the second BBS+ signature using the obtained public key associated with the owner system and the public key associated with the issuer system;
DID-based signature method using BBS + signature further comprising.
According to claim 3,
The VC includes a plurality of VCs,
The step of determining whether the owner system discloses each claim included in the VC and creating a VP associated with the owner system,
generating, by the owner system, a VP associated with the owner system by combining the plurality of VCs and determining whether to disclose each claim included in the plurality of VCs;
DID-based signature method using BBS + signature including.
According to claim 3,
the owner system sending a nonce value request to the verifier system; and
in response to receiving the nonce value request, the verifier system generating a nonce value;
Including more,
The step of the verifier system sending a VP submission request to the owner system,
sending, by the verifier system, a VP submission request including the generated nonce value to the owner system;
DID-based signature method using BBS + signature including.
A computer program stored in a computer-readable recording medium to execute the method according to any one of claims 1 to 6 on a computer.
As a DID-based signature system using BBS+ signature,
at least one processor configured to execute at least one computer readable program contained in the memory;
including,
The at least one program,
the owner system provides common values for BBS+ signatures to the issuer system;
the issuer system generates a first BBS+ signature associated with the issuer system using the provided common value;
The owner system transmits a DID-based VC issuance request to the issuer system,
in response to receiving the issuance request, the issuer system creates a VC associated with the owner system;
the issuer system associates the first BBS+ signature with the generated VC;
A DID-based signature system using BBS+ signatures comprising instructions for causing the issuer system to provide the owner system with a VC associated with the first BBS+ signature.
According to claim 8,
The at least one program,
obtain a public key associated with the issuer system from a blockchain network in response to the owner system receiving a VC associated with the first BBS+ signature;
The DID-based signature system using BBS+ signatures further comprising instructions for causing the owner system to perform signature verification on the first BBS+ signature using the obtained public key associated with the issuer system.
According to claim 9,
The at least one program,
The validator system sends a VP submission request to the owner system;
the owner system generates a second BBS+ signature associated with the owner system;
the owner system determines whether to disclose each claim included in the VC to create a VP associated with the owner system;
the owner system associates the second BBS+ signature with the created VP;
The DID-based signature system using BBS+ signatures further comprising instructions for causing the owner system to provide the verifier system with a VP associated with the second BBS+ signature.
According to claim 10,
The at least one program,
obtain a public key associated with the owner system and a public key associated with the issuer system from a blockchain network in response to the verifier system receiving the VP associated with the second BBS+ signature;
further comprising instructions for causing the verifier system to perform signature verification on the first BBS+ signature and the second BBS+ signature using the obtained public key associated with the owner system and the public key associated with the issuer system DID-based signature system using BBS+ signature.
According to claim 10,
The VC includes a plurality of VCs,
The at least one program,
DID-based using a BBS+ signature further comprising instructions for allowing the owner system to combine the plurality of VCs, determine whether to disclose each claim included in the plurality of VCs, and generate a VP associated with the owner system 's signature system.
According to claim 10,
The at least one program,
the owner system sends a nonce value request to the verifier system;
In response to receiving the nonce value request, the verifier system generates a nonce value;
The DID-based signature system using BBS+ signatures further comprising instructions for causing the verifier system to send a VP submission request containing the generated nonce value to the owner system.

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