CN113067702B - Identity-based encryption method supporting ciphertext equivalence test function - Google Patents

Identity-based encryption method supporting ciphertext equivalence test function Download PDF

Info

Publication number
CN113067702B
CN113067702B CN202110284847.7A CN202110284847A CN113067702B CN 113067702 B CN113067702 B CN 113067702B CN 202110284847 A CN202110284847 A CN 202110284847A CN 113067702 B CN113067702 B CN 113067702B
Authority
CN
China
Prior art keywords
user
ciphertext
representing
plaintext
private key
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Active
Application number
CN202110284847.7A
Other languages
Chinese (zh)
Other versions
CN113067702A (en
Inventor
王保仓
刘玉彬
段普
张本宇
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Xidian University
Original Assignee
Xidian University
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Xidian University filed Critical Xidian University
Priority to CN202110284847.7A priority Critical patent/CN113067702B/en
Publication of CN113067702A publication Critical patent/CN113067702A/en
Application granted granted Critical
Publication of CN113067702B publication Critical patent/CN113067702B/en
Active legal-status Critical Current
Anticipated expiration legal-status Critical

Links

Images

Classifications

    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04L—TRANSMISSION OF DIGITAL INFORMATION, e.g. TELEGRAPHIC COMMUNICATION
    • H04L9/00—Cryptographic mechanisms or cryptographic arrangements for secret or secure communications; Network security protocols
    • H04L9/32—Cryptographic mechanisms or cryptographic arrangements for secret or secure communications; Network security protocols including means for verifying the identity or authority of a user of the system or for message authentication, e.g. authorization, entity authentication, data integrity or data verification, non-repudiation, key authentication or verification of credentials
    • H04L9/3236—Cryptographic mechanisms or cryptographic arrangements for secret or secure communications; Network security protocols including means for verifying the identity or authority of a user of the system or for message authentication, e.g. authorization, entity authentication, data integrity or data verification, non-repudiation, key authentication or verification of credentials using cryptographic hash functions
    • H04L9/3242—Cryptographic mechanisms or cryptographic arrangements for secret or secure communications; Network security protocols including means for verifying the identity or authority of a user of the system or for message authentication, e.g. authorization, entity authentication, data integrity or data verification, non-repudiation, key authentication or verification of credentials using cryptographic hash functions involving keyed hash functions, e.g. message authentication codes [MACs], CBC-MAC or HMAC
    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04L—TRANSMISSION OF DIGITAL INFORMATION, e.g. TELEGRAPHIC COMMUNICATION
    • H04L63/00—Network architectures or network communication protocols for network security
    • H04L63/04—Network architectures or network communication protocols for network security for providing a confidential data exchange among entities communicating through data packet networks
    • H04L63/0428—Network architectures or network communication protocols for network security for providing a confidential data exchange among entities communicating through data packet networks wherein the data content is protected, e.g. by encrypting or encapsulating the payload
    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04L—TRANSMISSION OF DIGITAL INFORMATION, e.g. TELEGRAPHIC COMMUNICATION
    • H04L67/00—Network arrangements or protocols for supporting network services or applications
    • H04L67/01—Protocols
    • H04L67/10—Protocols in which an application is distributed across nodes in the network
    • H04L67/1097—Protocols in which an application is distributed across nodes in the network for distributed storage of data in networks, e.g. transport arrangements for network file system [NFS], storage area networks [SAN] or network attached storage [NAS]
    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04L—TRANSMISSION OF DIGITAL INFORMATION, e.g. TELEGRAPHIC COMMUNICATION
    • H04L9/00—Cryptographic mechanisms or cryptographic arrangements for secret or secure communications; Network security protocols
    • H04L9/06—Cryptographic mechanisms or cryptographic arrangements for secret or secure communications; Network security protocols the encryption apparatus using shift registers or memories for block-wise or stream coding, e.g. DES systems or RC4; Hash functions; Pseudorandom sequence generators
    • H04L9/0643—Hash functions, e.g. MD5, SHA, HMAC or f9 MAC
    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04L—TRANSMISSION OF DIGITAL INFORMATION, e.g. TELEGRAPHIC COMMUNICATION
    • H04L9/00—Cryptographic mechanisms or cryptographic arrangements for secret or secure communications; Network security protocols
    • H04L9/08—Key distribution or management, e.g. generation, sharing or updating, of cryptographic keys or passwords
    • H04L9/0816—Key establishment, i.e. cryptographic processes or cryptographic protocols whereby a shared secret becomes available to two or more parties, for subsequent use
    • H04L9/0838—Key agreement, i.e. key establishment technique in which a shared key is derived by parties as a function of information contributed by, or associated with, each of these
    • H04L9/0847—Key agreement, i.e. key establishment technique in which a shared key is derived by parties as a function of information contributed by, or associated with, each of these involving identity based encryption [IBE] schemes
    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04L—TRANSMISSION OF DIGITAL INFORMATION, e.g. TELEGRAPHIC COMMUNICATION
    • H04L9/00—Cryptographic mechanisms or cryptographic arrangements for secret or secure communications; Network security protocols
    • H04L9/08—Key distribution or management, e.g. generation, sharing or updating, of cryptographic keys or passwords
    • H04L9/0861—Generation of secret information including derivation or calculation of cryptographic keys or passwords
    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04L—TRANSMISSION OF DIGITAL INFORMATION, e.g. TELEGRAPHIC COMMUNICATION
    • H04L9/00—Cryptographic mechanisms or cryptographic arrangements for secret or secure communications; Network security protocols
    • H04L9/30—Public key, i.e. encryption algorithm being computationally infeasible to invert or user's encryption keys not requiring secrecy
    • H04L9/3066—Public key, i.e. encryption algorithm being computationally infeasible to invert or user's encryption keys not requiring secrecy involving algebraic varieties, e.g. elliptic or hyper-elliptic curves
    • H04L9/3073—Public key, i.e. encryption algorithm being computationally infeasible to invert or user's encryption keys not requiring secrecy involving algebraic varieties, e.g. elliptic or hyper-elliptic curves involving pairings, e.g. identity based encryption [IBE], bilinear mappings or bilinear pairings, e.g. Weil or Tate pairing

Landscapes

  • Engineering & Computer Science (AREA)
  • Computer Security & Cryptography (AREA)
  • Computer Networks & Wireless Communication (AREA)
  • Signal Processing (AREA)
  • Theoretical Computer Science (AREA)
  • Power Engineering (AREA)
  • Computing Systems (AREA)
  • Algebra (AREA)
  • Mathematical Physics (AREA)
  • Pure & Applied Mathematics (AREA)
  • Mathematical Optimization (AREA)
  • Mathematical Analysis (AREA)
  • General Physics & Mathematics (AREA)
  • Physics & Mathematics (AREA)
  • Computer Hardware Design (AREA)
  • General Engineering & Computer Science (AREA)
  • Storage Device Security (AREA)

Abstract

The invention discloses an identity base encryption method supporting an equivalence test function, which mainly solves the problem that the identity base encryption efficiency supporting the equivalence test function under a standard model in the prior art is low. The implementation scheme is as follows: the key generation center generates a master key according to the security parameters, and generates a private key and an authorization trapdoor of a user according to the master key and the public key; the user sends the authorization trapdoor to a designated server through a secret channel; a user encrypts a plaintext message and a hash value thereof in parallel; the decryptor inputs the ciphertext and the private key, and decrypts the ciphertext to obtain a plaintext; the server takes the authorized trapdoors and the ciphertext of the two users as input to perform equivalence test; and the server returns a test result to the user, if the test result is 1, the plaintext of the two users is equal, otherwise, the plaintext is not equal. Compared with an identity-based encryption scheme supporting an equivalent test function under a standard model, the identity-based encryption method is higher in computing efficiency and more outstanding in performance, and can be applied to cloud storage and dense data retrieval of big data.

Description

Identity-based encryption method supporting ciphertext equivalence test function
Technical Field
The invention belongs to the technical field of information security, and particularly relates to an identity-based encryption method supporting a ciphertext equivalence test function, which can be applied to cloud storage and ciphertext data retrieval of big data.
Background
As cloud computing technology is widely used, more and more private data is uploaded to the cloud server. However, there are still some careless mistakes in the protection of the privacy and data information of the user by the cloud server. In recent years, news in which private data stored in a cloud server by a user is leaked is frequently seen. For example, in 11 months in 2018, information announced by the luxury company that 5 hundred million tenants in a hotel wedding room under flag was leaked; in the same year and 12 months, 3 million unknown user data of the social platform are sold in the darknet, and the like. The leakage of the private data of the user may cause a great risk to the user. Accordingly, cryptographic techniques for achieving user privacy data protection in cloud computing environments are beginning to be widely studied. Generally, a user encrypts private data and uploads the encrypted data to a server, but data management in a ciphertext state in the server becomes a new problem, namely, the original characteristics and structure of the data are lost after encryption, so that various operations on a plaintext are difficult to perform on a ciphertext. For example, if a user wants to perform query operation on data in a ciphertext state, all data must be downloaded, decrypted and then queried, which greatly increases the calculation and transmission overhead and thus is very inefficient. To this end, a ciphertext equivalence test encryption technique is proposed to solve this problem.
The cipher text equivalence test encryption technology is used for solving the matching problem of different public key encryption data, namely a tester can judge whether two sections of cipher texts encrypted by different public keys contain the same message on the premise of not decrypting the cipher texts. The ciphertext equivalence testing technology has very wide application prospects, such as classification of encrypted data according to tags, filtering and archiving of e-mails, and matching and searching of patients with the same disease in an electronic medical system.
However, most of the existing identity-based encryption schemes supporting the ciphertext equivalence test function are provably safe under a random language prediction model. The random oracle model is an important concept of a provable security theory, and refers to a cryptography tool of using a random oracle in security certification of a cryptographic scheme. The random prediction machine is a hash function which determines, discloses and outputs random uniformity. In the implementation process of the scheme, only a real hash function can be used for replacing the random prediction machine, so that an adversary can possibly attack by using the defects of the real hash function. The proof model without the use of a random oracle is called the standard model. Under the standard model, the security of the scheme only depends on the standard properties of the hash function, such as collision resistance, and the adversary is limited only by time and computing power without other assumptions. A higher level of security can be demonstrated for a secure cryptographic scheme under the standard model.
Lee et al, in 2016, in the paper "Public Key Encryption with authentication Test in the Standard Model" (2016/1182,2016, cryptographic equivalent garment archive), disclose an identity based Encryption method supporting ciphertext equivalence Test functions under a Standard Model. Firstly, generating a master key according to security parameters, and then generating a private key for a user according to the master key and a user public key; encrypting the plaintext message by the user to obtain a ciphertext, and generating an authorization trapdoor according to the private key; and sending the authorized trapdoor to a designated server through a secret channel; and the server performs equivalence test on the ciphertext according to the authorization modes specified by different users and returns a test result to the user. The scheme has low efficiency and no practicability due to the application of the complex three-layer identity-based encryption and the strong one-time signature technology which can not be forged.
Disclosure of Invention
The invention aims to provide an identity base encryption method supporting the equivalence test function aiming at the defects of the prior art so as to improve the efficiency of identity base encryption supporting the equivalence test function under a standard model.
In order to achieve the purpose, the technical scheme adopted by the invention is as follows:
(1) initializing a system:
(1a) inputting a security parameter λ, and giving a bilinear map e:
Figure BDA0002980026300000021
let g be
Figure BDA0002980026300000022
Is given as e (g, g) is
Figure BDA0002980026300000023
A generator ofIn (1),
Figure BDA0002980026300000024
is a group of multiplication cycles of the order of a prime number p,
Figure BDA0002980026300000025
a multiplication loop group of order prime p;
(1b) the key generation center KGC selects two cryptographic hash functions H1:
Figure BDA0002980026300000026
H:
Figure BDA0002980026300000027
And is arranged at
Figure BDA0002980026300000028
Randomly selecting 5 different master key generation stage parameters alpha and beta1,β2,β3,β4Wherein, 0,1*Representing a bit string of arbitrary length,
Figure BDA0002980026300000029
represents the set 0,1, …, p-1;
(1c) and the key generation center calculates and outputs a system master key MSK and a system public parameter PP according to the selected hash function and the random parameter:
MSK＝(α,β1,β2,β3,β4)
Figure BDA00029800263000000210
wherein, g1＝gα,
Figure BDA00029800263000000211
(2) And (3) generating a user private key:
(2a) entering a user identity identifier
Figure BDA00029800263000000212
A system master key MSK and a system public parameter PP;
(2b) KGC is in
Figure BDA0002980026300000031
Randomly selecting 4 different user private key generation stage parameters r1,r2,r3,r4And calculates the user private key dID：
Figure BDA0002980026300000032
(3) Authorized trapdoor extraction:
user generated authorization trapdoor td ═ (d)7,d8) And sending the authorized trapdoor to a designated server through a secret channel;
(4) encryption:
(4a) inputting a plaintext message
Figure BDA0002980026300000033
A user identity identifier ID and a public parameter PP;
(4b) the user is at
Figure BDA0002980026300000034
And randomly selecting a parameter s, and calculating a ciphertext CT:
CT＝(C1,C2,C3,C4,C5)＝((g1g-ID)s,e(g,g)s,e(h3,g)s·m,e(h4,g)s·H(m),e(h1,g)se(h2,g)sw)
wherein w ═ H1(C1,C2,C3,C4)；
(4c) The user uploads the ciphertext CT to the cloud server;
(5) and (3) decryption:
(5a) inputting the ciphertext CT corresponding to the ID and the user private key dIDAnd system common parameters PP, solutionThe secret is calculated as w ═ H1(C1,C2,C3,C4)；
(5b) And (3) verification:
Figure BDA0002980026300000035
if true, two intermediate results are computed:
Figure BDA0002980026300000036
and
Figure BDA0002980026300000037
if H (m ') -H ', outputting correct plaintext m (═ m '), otherwise, failing to decrypt;
(6) and (3) testing:
(6a) let the plaintext message of user i be miUser j plaintext message is mjRespectively inputting ciphertext CT of user iiAuthorized trapdoor tdiAnd ciphertext CT of user jjAuthorized trapdoor tdj；
(6b) According to the ciphertext and the trapdoor given in the step (6a), the server calculates the hash value H (m) of the plaintext message of the user ii) And hash value H (m) of user j's plaintext messagej) And judging whether the two are equal:
if H (m)i)＝H(mj) If so, outputting 1 to indicate that the plaintext messages of the user i and the user j are equal, and establishing contact between the user i and the user j through the cloud server;
otherwise, outputting 0, indicating that the plaintext messages of the user i and the user j are not equal, and the cloud server re-executes the test algorithm to match other users with the plaintext messages equal to those of the respective users.
Compared with the prior art, the invention has the following advantages:
1) according to the invention, as the ciphertext is constructed by encrypting the plaintext and the hash value thereof in parallel, the cloud server obtains the hash values of the plaintext of two users by the calculation of the authorization trap door, and realizes the equivalent test function by judging whether the plaintext and the hash value are equal or not;
2) compared with the scheme of Lee and the like, the invention has the advantages that as fewer public parameters are selected, the key and the ciphertext size are shorter, and the communication overhead is reduced; secondly, the statistics of the operation times involved in the encryption algorithm, the decryption algorithm and the test algorithm in the invention shows that compared with the scheme of Lee et al, the calculation efficiencies of the encryption algorithm, the decryption algorithm and the test algorithm in the invention are respectively improved by 60%, 70% and 65%.
Drawings
FIG. 1 is a flow chart of an implementation of the present invention.
Detailed Description
Embodiments of the invention are described in further detail below with reference to the accompanying drawings:
referring to fig. 1, the identity-based encryption method supporting the ciphertext equivalence test function in this embodiment includes the following steps:
step 1, system initialization.
(1.1) inputting a security parameter lambda, and giving a bilinear mapping e:
Figure BDA0002980026300000041
let g be
Figure BDA0002980026300000042
Is given as e (g, g) is
Figure BDA0002980026300000043
A generator of (a), wherein,
Figure BDA0002980026300000044
is a group of multiplication cycles of the order of a prime number p,
Figure BDA0002980026300000045
a multiplication loop group of order prime p;
(1.2) selecting two cryptographic hash functions H by the key generation center KGC1:
Figure BDA0002980026300000046
H:
Figure BDA0002980026300000047
And is arranged at
Figure BDA0002980026300000048
Randomly selecting 5 different master key generation stage parameters alpha and beta1,β2,β3,β4Wherein, 0,1*Representing a bit string of arbitrary length,
Figure BDA0002980026300000049
represents the set 0,1, …, p-1;
(1.3) the key generation center calculates and outputs a system master key MSK and a system public parameter PP according to the selected hash function and the random parameter:
MSK＝(α,β1,β2,β3,β4)
Figure BDA0002980026300000051
wherein, g1＝gα,
Figure BDA0002980026300000052
And 2, generating a user private key.
(2.1) entering a user identity identifier
Figure BDA0002980026300000053
A system master key MSK and a system public parameter PP;
(2.2) KGC in
Figure BDA0002980026300000054
Randomly selecting 4 different user private key generation stage parameters r1,r2,r3,r4And calculates the user private key dID：
Figure BDA0002980026300000055
Wherein d is1To d8Represents 8 parts of the user's private key, namely:
d1＝r1，
Figure BDA0002980026300000056
d3＝r2，
Figure BDA0002980026300000057
d5＝r3，
Figure BDA0002980026300000058
d7＝r4，
Figure BDA0002980026300000059
and 3, authorizing trap door extraction.
Inputting a user private key dID＝(d1,d2,d3,d4,d5,d6,d7,d8) The user extracts the seventh and eighth parts from the private key as authorization trapdoors: td is (d)7,d8) And sends the authorization trapdoor td to the designated server through the secret channel.
And 4, encrypting the plaintext message by the user.
(4.1) input plaintext message
Figure BDA00029800263000000510
A user identity identifier ID and a public parameter PP;
(4.2) the user is at
Figure BDA00029800263000000511
And randomly selecting a parameter s, and calculating a ciphertext CT:
CT＝(C1,C2,C3,C4,C5)＝((g1g-ID)s,e(g,g)s,e(h3,g)s·m,e(h4,g)s·H(m),e(h1,g)se(h2,g)sw) Wherein, C1To C5Represents 5 parts of the ciphertext, namely:
C1＝(g1g-ID)s
C2＝e(g,g)s
C3＝e(h3,g)s·m
C4＝e(h4,g)s·H(m)
C5＝e(h1,g)se(h2,g)sw，w＝H1(C1,C2,C3,C4)；
and (4.3) uploading the ciphertext CT to a cloud server by the user.
And 5, the decryptor decrypts the ciphertext.
(5.1) inputting the ciphertext CT and the user private key dIDAnd system common parameters PP, the decryptor first calculates C1To C4Hash value of (2): w ═ H1(C1,C2,C3,C4)；
(5.2) verifying:
Figure BDA0002980026300000061
whether or not:
if so, two intermediate results are computed:
Figure BDA0002980026300000062
and
Figure BDA0002980026300000063
executing (5.3), otherwise, failing to decrypt;
(5.3) verifying whether H (m ') is true, if so, outputting correct plaintext m (═ m'), otherwise, failing to decrypt.
And 6, executing the equivalence test by the cloud server.
(6.1) let the plaintext message of user i be miUser j plaintext message is mjRespectively inputting ciphertext CT of user iiAuthorized trapdoor tdiAnd ciphertext CT of user jjAuthorized trapdoor tdjThese parameters are respectively expressed as follows:
CTi＝(C1,i,C2,i,C3,i,C4,i,C5,i)
CTj＝(C1,j,C2,j,C3,j,C4,j,C5,j)
tdi＝(d7,i,d8,i)
tdj＝(d7,j,d8,j)
wherein, CTiConsists of five parts, C1,i,C2,i,C3,i,C4,i,C5,iRespectively representing the first part to the fifth part of the user i ciphertext;
CTjconsists of five parts, C1,j,C2,j,C3,j,C4,j,C5,jRespectively representing the first part to the fifth part of the ciphertext of the user j;
tdiconsisting of two-part private keys of user i, d7,i,d8,iA seventh part and an eighth part respectively representing a private key of the user i;
tdjconsisting of two-part private keys of user j, d7,j,d8,jA seventh part and an eighth part respectively representing a private key of the user i;
(6.2) according to the ciphertext and the trapdoor given in (6.1), the server calculates the hash value H (m) of the plaintext message of the user ii) And hash value H (m) of user j's plaintext messagej)：
Figure BDA0002980026300000064
Figure BDA0002980026300000065
Wherein, C1,iRepresenting a first part of the ciphertext of user i, C2,iA second part, C, representing the ciphertext of user i4,iFourth part, d, representing user i's ciphertext7,iA seventh part, d, representing the private key of user i8,iAn eighth portion representing a private key of user i; c1,jRepresenting a first part, C, of the ciphertext of user j2,jRepresenting a second part, C, of the ciphertext of user j4,jFourth part, d, representing user j ciphertext7,jRepresenting a seventh part of the private key of user j, d8,jAn eighth portion representing a private key of user j;
(6.3) determination of H (m)i) And H (m)j) Whether the two are equal:
if H (m)i)＝H(mj) If so, outputting 1, indicating that the plaintext messages of the user i and the user j are equal, and establishing contact between the user i and the user j through the cloud server;
if H (m)i)≠H(mj) And outputting 0, namely that the plaintext messages of the user i and the user j are not equal, and re-executing the test algorithm by the cloud server to match other users with the plaintext messages equal to the users.
While the invention has been particularly shown and described with reference to exemplary embodiments thereof, it will be understood by those skilled in the art that various changes in form and details may be made therein without departing from the spirit and scope of the invention.

Claims (3)

1. An identity-based encryption method supporting ciphertext equivalence test function is characterized by comprising the following steps:
(1) initializing a system:
(1a) inputting security parameters, giving a bilinear map
Figure FDA0003415598590000011
Let g be
Figure FDA0003415598590000012
Is given as e (g, g) is
Figure FDA0003415598590000013
A generator of (a), wherein,
Figure FDA0003415598590000014
is a group of multiplication cycles of the order of a prime number p,
Figure FDA0003415598590000015
a multiplication loop group of order prime p;
(1b) the key generation center KGC selects two cryptographic hash functions
Figure FDA0003415598590000016
And is arranged at
Figure FDA0003415598590000017
Randomly selecting 5 different master key generation stage parameters alpha and beta1,β2,β3,β4Wherein, 0,1*Representing a bit string of arbitrary length,
Figure FDA0003415598590000018
represents the set 0,1, …, p-1;
(1c) and the key generation center calculates and outputs a system master key MSK and a system public parameter PP according to the selected hash function and the random parameter:
MSK＝(α,β1,β2,β3,β4)
Figure FDA0003415598590000019
wherein, g1＝gα,
Figure FDA00034155985900000110
(2) And (3) generating a user private key:
(2a) entering a user identityIdentifier
Figure FDA00034155985900000111
A system master key MSK and a system public parameter PP;
(2b) KGC is in
Figure FDA00034155985900000112
Randomly selecting 4 different user private key generation stage parameters r1,r2,r3,r4And calculates the user private key dID：
Figure FDA00034155985900000113
(3) Authorized trapdoor extraction:
user generated authorization trapdoor td ═ (d)7,d8) And sending the authorized trapdoor to a designated server through a secret channel;
(4) encryption:
(4a) inputting a plaintext message
Figure FDA00034155985900000114
A user identity identifier ID and a public parameter PP;
(4b) the user is at
Figure FDA0003415598590000021
And randomly selecting a parameter s, and calculating a ciphertext CT:
CT＝(C1,C2,C3,C4,C5)＝((g1g-ID)s,e(g,g)s,e(h3,g)s·m,e(h4,g)s·H(m),e(h1,g)se(h2,g)sw)，
wherein w ═ H1(C1,C2,C3,C4)；
(4c) The user uploads the ciphertext CT to the cloud server;
(5) and (3) decryption:
(5a) inputting the ciphertext CT corresponding to the ID and the user private key dIDAnd the system common parameter PP, the decryptor first calculates w ═ H1(C1,C2,C3,C4)；
(5b) And (3) verification:
Figure FDA0003415598590000022
if true, two intermediate results are computed:
Figure FDA0003415598590000023
and
Figure FDA0003415598590000024
if H (m ') -H ', outputting correct plaintext m (═ m '), otherwise, failing to decrypt;
(6) and (3) testing:
(6a) let the plaintext message of user i be miUser j plaintext message is mjRespectively inputting ciphertext CT of user iiAuthorized trapdoor tdiAnd ciphertext CT of user jjAuthorized trapdoor tdj；
(6b) According to the ciphertext and the trapdoor given in the step (6a), the server calculates the hash value H (m) of the plaintext message of the user ii) And hash value H (m) of user j's plaintext messagej) And judging whether the two are equal:
if H (m)i)＝H(mj) If so, outputting 1 to indicate that the plaintext messages of the user i and the user j are equal, and establishing contact between the user i and the user j through the cloud server;
otherwise, outputting 0, indicating that the plaintext messages of the user i and the user j are not equal, and the cloud server re-executes the test algorithm to match other users with the plaintext messages equal to those of the respective users.
2. The method according to claim 1, wherein the ciphertext CT of the user i input in (6a)iAuthorized trapdoor tdiAnd ciphertext CT of user jjAuthorized trapdoor tdjRespectively watchShown below:
CTi＝(C1,i,C2,i,C3,i,C4,i,C5,i)
CTj＝(C1,j,C2,j,C3,j,C4,j,C5,j)
tdi＝(d7,i,d8,i)
tdj＝(d7,j,d8,j)
wherein, CTiConsists of five parts, C1,i,C2,i,C3,i,C4,i,C5,iRespectively representing the first part to the fifth part of the user i ciphertext;
CTjconsists of five parts, C1,j,C2,j,C3,j,C4,j,C5,jRespectively representing the first part to the fifth part of the ciphertext of the user j;
tdiconsisting of two-part private keys of user i, d7,i,d8,iA seventh part and an eighth part respectively representing a private key of the user i;
tdjconsisting of two-part private keys of user j, d7,j,d8,jRepresenting a seventh portion and an eighth portion, respectively, of the private key of user j.
3. The method of claim 1, wherein the hash value of the plaintext message for user i, H (m), is calculated in (6b)i) And hash value H (m) of user j's plaintext messagej) The formula is as follows:
Figure FDA0003415598590000031
Figure FDA0003415598590000032
wherein, C1,iRepresenting a first part of the ciphertext of user i, C2,iA second part, C, representing the ciphertext of user i4,iFourth part, d, representing user i's ciphertext7,iA seventh part, d, representing the private key of user i8,iAn eighth portion representing a private key of user i; c1,jRepresenting a first part, C, of the ciphertext of user j2,jRepresenting a second part, C, of the ciphertext of user j4,jFourth part, d, representing user j ciphertext7,jRepresenting a seventh part of the private key of user j, d8,jRepresenting an eighth portion of the private key of user j.
CN202110284847.7A 2021-03-17 2021-03-17 Identity-based encryption method supporting ciphertext equivalence test function Active CN113067702B (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
CN202110284847.7A CN113067702B (en) 2021-03-17 2021-03-17 Identity-based encryption method supporting ciphertext equivalence test function

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
CN202110284847.7A CN113067702B (en) 2021-03-17 2021-03-17 Identity-based encryption method supporting ciphertext equivalence test function

Publications (2)

Publication Number Publication Date
CN113067702A CN113067702A (en) 2021-07-02
CN113067702B true CN113067702B (en) 2022-03-22

Family

ID=76560879

Family Applications (1)

Application Number Title Priority Date Filing Date
CN202110284847.7A Active CN113067702B (en) 2021-03-17 2021-03-17 Identity-based encryption method supporting ciphertext equivalence test function

Country Status (1)

Country Link
CN (1) CN113067702B (en)

Families Citing this family (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN113794554A (en) * 2021-07-30 2021-12-14 四川航天职业技术学院(四川航天高级技工学校) Fine-grained authorization equivalence testing method based on certificateless encryption
CN113992397B (en) * 2021-10-26 2022-10-21 电子科技大学 Efficient public key encryption method supporting differential equation test
CN114756011B (en) * 2022-05-27 2023-05-12 西安电子科技大学 Intelligent home anomaly detection method based on TV-PKEET
CN115473703B (en) * 2022-08-24 2024-04-12 华南农业大学 Authentication ciphertext equivalent test method, device, system and medium based on identity

Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
EP2972939A1 (en) * 2013-03-14 2016-01-20 Samsung Electronics Co., Ltd. Information delivery system with advertising mechanism and method of operation thereof
CN107734054A (en) * 2017-11-06 2018-02-23 福州大学 Encryption data searching system in safe cloud storage
CN109902501A (en) * 2019-03-19 2019-06-18 中国海洋大学 A kind of structuring encryption method and system carrying out equality test based on cloud service platform
CN110162998A (en) * 2019-04-29 2019-08-23 华南农业大学 Identity ciphering equivalence test method, device, system and medium based on user group

Family Cites Families (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN106549753B (en) * 2016-10-18 2019-07-09 电子科技大学 A kind of encryption method that the support ciphertext of identity-based compares
CN108737390B (en) * 2018-05-03 2020-05-15 华南农业大学 Authentication method and system for protecting user name privacy

Patent Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
EP2972939A1 (en) * 2013-03-14 2016-01-20 Samsung Electronics Co., Ltd. Information delivery system with advertising mechanism and method of operation thereof
CN107734054A (en) * 2017-11-06 2018-02-23 福州大学 Encryption data searching system in safe cloud storage
CN109902501A (en) * 2019-03-19 2019-06-18 中国海洋大学 A kind of structuring encryption method and system carrying out equality test based on cloud service platform
CN110162998A (en) * 2019-04-29 2019-08-23 华南农业大学 Identity ciphering equivalence test method, device, system and medium based on user group

Non-Patent Citations (3)

* Cited by examiner, † Cited by third party
Title
"Efficient and secure identity-based encryption scheme with equality";Libing Wu等;《Future Generation Computer Systems》;20170831;全文 *
"Efficient public key encryption with equality test in the standard model";Kai Zhang等;《Theoretical Computer Science》;20180824;全文 *
"Public key encryption with equality test in the standard model";Hyung Tae Lee等;《Information Sciences》;20200430;全文 *

Also Published As

Publication number Publication date
CN113067702A (en) 2021-07-02

Similar Documents

Publication Publication Date Title
CN113067702B (en) Identity-based encryption method supporting ciphertext equivalence test function
CN110213042B (en) Cloud data deduplication method based on certificate-free proxy re-encryption
KR101493212B1 (en) Method and system for id-based encryption and decryption
KR101685810B1 (en) System and method for key exchange based on authtication information
CN109543434B (en) Block chain information encryption method, decryption method, storage method and device
CN106130716A (en) Cipher key exchange system based on authentication information and method
CN109981265B (en) Identity-based ciphertext equivalence determination method without using bilinear pairings
CN110120873B (en) Frequent item set mining method based on cloud outsourcing transaction data
CN106549753A (en) The encipherment scheme that a kind of support ciphertext of identity-based compares
CN109873699A (en) A kind of voidable identity public key encryption method
US10484182B2 (en) Encrypted text verification system, method, and recording medium
CN109889332A (en) Equation testing encryption method based on certificate
CN112866227A (en) File authorization protection method and system
Zhang et al. Secdedup: Secure encrypted data deduplication with dynamic ownership updating
CN112804052B (en) User identity encryption method based on composite order group
CN112560075B (en) Lightweight searchable encryption method and device based on elliptic curve
CN107454059B (en) Search encryption method based on sequence cipher in cloud storage environment
Abo-Alian et al. Auditing-as-a-service for cloud storage
CN116346336B (en) Key distribution method based on multi-layer key generation center and related system
TSENG et al. Short Paper_
CN115473703B (en) Authentication ciphertext equivalent test method, device, system and medium based on identity
Salman et al. A homomorphic cloud framework for big data analytics based on elliptic curve cryptography
CN114760072B (en) Signature and signature verification method, device and storage medium
Shen et al. A multivariate public key encryption scheme with equality test
CN113656818B (en) Trusted-free third party cloud storage ciphertext deduplication method and system meeting semantic security

Legal Events

Date Code Title Description
PB01 Publication
PB01 Publication
SE01 Entry into force of request for substantive examination
SE01 Entry into force of request for substantive examination
GR01 Patent grant
GR01 Patent grant