WO2019090988A1 - 一种基于动态规则的密码学属性基访问控制方法与系统 - Google Patents

一种基于动态规则的密码学属性基访问控制方法与系统 Download PDF

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WO2019090988A1
WO2019090988A1 PCT/CN2018/074646 CN2018074646W WO2019090988A1 WO 2019090988 A1 WO2019090988 A1 WO 2019090988A1 CN 2018074646 W CN2018074646 W CN 2018074646W WO 2019090988 A1 WO2019090988 A1 WO 2019090988A1
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policy
attribute
token
cryptographic
access
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PCT/CN2018/074646
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English (en)
French (fr)
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朱岩
于汝云
尹昊
秦瑶
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北京科技大学
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Priority to US16/759,917 priority Critical patent/US11425171B2/en
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    • 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
    • H04L63/20—Network architectures or network communication protocols for network security for managing network security; network security policies in general
    • 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
    • H04L63/0407—Network architectures or network communication protocols for network security for providing a confidential data exchange among entities communicating through data packet networks wherein the identity of one or more communicating identities is hidden
    • 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
    • H04L63/06—Network architectures or network communication protocols for network security for supporting key management in a packet data network
    • 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
    • H04L63/08—Network architectures or network communication protocols for network security for authentication of entities
    • H04L63/0807—Network architectures or network communication protocols for network security for authentication of entities using tickets, e.g. Kerberos
    • 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
    • H04L63/10—Network architectures or network communication protocols for network security for controlling access to devices or network resources
    • 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
    • H04L9/088—Usage controlling of secret information, e.g. techniques for restricting cryptographic keys to pre-authorized uses, different access levels, validity of crypto-period, different key- or password length, or different strong and weak cryptographic algorithms
    • 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
    • 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
    • H04L9/3263—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 involving certificates, e.g. public key certificate [PKC] or attribute certificate [AC]; Public key infrastructure [PKI] arrangements
    • H04L9/3268—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 involving certificates, e.g. public key certificate [PKC] or attribute certificate [AC]; Public key infrastructure [PKI] arrangements using certificate validation, registration, distribution or revocation, e.g. certificate revocation list [CRL]
    • 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
    • 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
    • H04L63/045—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 wherein the sending and receiving network entities apply hybrid encryption, i.e. combination of symmetric and asymmetric encryption

Definitions

  • the invention mainly belongs to the field of information technology, and particularly relates to a cryptographic attribute based access control method and system based on dynamic rules.
  • the method and system support policy scalable and cryptographic access to dynamic acquisition of attributes, suitable for large-scale organizations or information systems, and can be applied to environments such as cloud computing, grid computing, distributed computing, and the like.
  • Access control is one of the core technologies to ensure the security of information systems. Its mission is to ensure that digital assets are not illegally used. It usually refers to different authorized accesses of the subject itself or its resources according to certain control policies or permissions.
  • Attribute-based Access Control uses the attributes of related entities (such as subject, object, action, environment, etc.) (representing a certain nature and relationship of things) as the basis of authorization to achieve access control, providing more flexible, dynamic, fine-grained authorization control. Can adapt well to this open network environment.
  • Attribute-based access control is a fine-grained, multi-factor access control method based on access policies. It consists of four entities, which use S, O, A, E to represent the set of attributes of the subject, object, action, and environment; each attribute set includes several attributes, each of which can be assigned one or more attribute values. Attributes can be divided into static attributes and dynamic attributes. Environment attributes are usually a kind of dynamic attributes different from subject, object and action, such as access time, location, device, historical information, etc. Dynamic, time-varying features.
  • the attribute-based access control defines the authorization relationship between the entities through the access control policy (referred to as the access control policy, Policy).
  • the policy consists of a series of rules (Rules) to constrain whether the subject S is in the environment E. Allows access to object O with action A.
  • the access control policy is determined based on the attribute values of the subject, the object, the action, and the environment, thereby determining whether the requester's request is authorized.
  • the diversity of attributes, the dynamics, and the flexibility of the access control strategy make ABAC flexible and scalable. At the same time, secure anonymous access is possible because there is no need to make policy decisions against the requester's real name. This is very important in an open environment.
  • the attribute-based access control model includes the following basic functional modules, which are described as follows:
  • PAP Policy Administration Point
  • PIP Policy Information Point
  • PDP Policy Enforcement Point
  • PDP Policy Decision Point
  • Attribute-based Encryption (ABE) technology combines access policy with ciphertext, attribute assignment and user key. Users can decrypt ciphertext if and only if the attributes in the user's private key satisfy the ciphertext access. Strategy. However, in this ABE, the access policy is fixed in the ciphertext and cannot be changed, so it is not scalable. Secondly, the attribute assignment and the key combination are fixed and cannot be dynamic.
  • the invention proposes a cryptographic attribute-based access control method and system based on dynamic rules, and is an attribute-based access control method and system using cryptography.
  • the protected object is stored in an encrypted form, which means that the object is placed in an open, insecure environment and is not unauthorized access, but only meets the policy requirements of the attribute-based access control. Access can be authorized to decrypt the object, which ensures that data in an insecure environment can be authorized to access according to security policies.
  • the method and system of the present invention can support a complete attribute-based access control model, and can support rule-based, scalable cryptographic access policy generation, and support dynamic cryptographic attribute acquisition.
  • the method and system make the authorized access process of the subject to the object efficient, dynamic and secure, and also ensure the consistency and integrity of the access control rules in the system.
  • a cryptographic attribute-based access control system based on dynamic rules, in which protected objects are stored in an encrypted form, and only accesses satisfying the access policy requirements in the attribute-based access control can be authorized to decrypt the object, wherein, access Authorization is based on the security token Token, which ensures that data in an insecure environment can be authorized to access according to security policies. It also supports policy extensibility and dynamic acquisition of attributes.
  • system includes three storage modules and one sensing module:
  • Policy storage module PSM used to store access policies
  • Attribute storage module ASM used to store attributes of entities in the system and attribute assignments
  • Object storage module OSM used to store the encrypted object
  • Environment Awareness Module EPM used to obtain environment attributes and attribute assignments in real time and dynamically;
  • the system also includes four execution units, as follows:
  • the policy generation unit PGU selects an access policy from the policy storage module PSM, generates a cryptographic representation CP of the access policy, and the cryptographic representation CP of the access policy is a cryptographic strategy, and the cryptography is performed.
  • the policy is provided to the policy decision unit PDU;
  • a token generating unit TGU acquires an attribute assignment of a specific attribute from the attribute storage module ASM and the environment aware module EPM, and completes a cryptographic representation of the attribute assignment, that is, a security attribute token. AttToken, finally providing the security attribute token AttToken to the policy decision unit PDU;
  • Policy decision unit PDU the policy decision unit PDU obtains the cryptographic policy from the policy generation unit PGU, obtains the security attribute token AttToken from the token generation unit TGU, and cryptographically The strategy performs cryptographic determination, and finally provides the determination result information, that is, the security decryption token DecToken, to the resource decryption unit RDU;
  • Resource decryption unit RDU the resource decryption unit RDU decrypts the resource according to the security decryption token DecToken returned by the policy determination unit PDU, that is, if and only if the policy determination unit PDU determines to pass, the resource
  • the decryption unit RDU can decrypt and recover the encrypted resource.
  • the system adopts an attribute-based access control model ABAC, including: an entity attribute set, an access policy, and an authorization process:
  • Entity attribute set The entity includes four attribute entities: subject, object, action, environment, and uses (S, O, A, E) to represent the attribute set of the four entities, and the policy center P for managing the security policy. ;
  • Authorization process is to obtain attribute values v 1 , v 2 ,..., v n ⁇ x 1 ,x 2 ,...,x n from each entity and match the specified access policy, ie to P(v 1 , v 2 ,...,v n ) The process of making a valuation and determining whether the access is authorized.
  • the access policy is composed of one or more rules having the same grammatical structure as the access policy and combined into a policy by Boolean logic;
  • the rules can be represented by a Boolean function whose input is an attribute variable
  • Boolean functions are constructed by Boolean logic acting on a number of predicates, each predicate being a logical decision formed by an operator acting on an attribute variable; wherein the Boolean logic includes AND, OR, and NOT; Symbols include equal, greater than, less than, belong to, not belong to, include.
  • the security attribute token AttToken and the security decryption token DecToken belong to a security token Token
  • the security token Token is a temporary, unforgeable, publicly verifiable digital certificate, which can be verified by cryptography. Method to prove its validity, the access authorization in the system is based on the security token Token;
  • the security attribute token AttToken is a cryptographic certificate of attribute assignment, that is, includes non-tamperable attributes and attribute value information, and also includes time-varying parameter information to ensure unforgeability and instantaneous validity of the token;
  • the time varying parameter information includes a random number, a count value, and a time stamp;
  • the security decryption token DecToken is a cryptographic certificate for decrypting a secret, and includes secret information and variable parameter information for decrypting a decryption key required for a specific resource.
  • the object is stored in an encrypted form, and the encryption algorithm may be any symmetric encryption algorithm and asymmetric encryption algorithm;
  • the distributed authorization is implemented by using the security attribute token instead of the decryption key, and the token is publicly verifiable;
  • security attribute token is dynamically obtained, and the same subject may have the same access to the same object in different environments, and the policy determination result may be different;
  • the cryptographic policy in the policy generating unit is dynamically generated, allowing the cryptographic policy to be changed in real time and affecting the access authorization result;
  • Whether the resource can be decrypted is determined by the policy determining unit. If and only if the determination is passed, the resource can be decrypted, and the subject can access the object; specifically, the resource decrypting unit RDU decrypts and restores the encrypted resource by using the secondary decryption. Form: If and only if the policy decision unit PDU decides to pass, the resource decryption unit RDU first decrypts the session key ek using the secure decryption token DecToken, and then decrypts the resource with the session key ek.
  • the system can implement policy scalability and attribute assignment dynamics, and the policy scalability guarantee rules can be added, modified or revoked according to requirements, and the change can immediately access the (encrypted) resources in the system.
  • Authorization has an impact; attribute assignment dynamics ensures that the system can get the current attributes of the entity in real time.
  • a cryptographic attribute based access control method based on dynamic rules the method adopting the system, and the method comprises:
  • Resource encryption process the object is stored in the object storage module OSM in an encrypted form, and all attribute information of the object is recorded in the attribute storage module ASM;
  • the subject requests access: a certain entity issues an access request to the encrypted object, the resource decryption unit RDU receives the request, and invokes the policy decision unit PDU to perform cryptographic determination on the request;
  • the policy decision unit PDU After receiving the information of the resource decryption unit RDU, the policy decision unit PDU issues a policy query request to the policy generation unit PGU, and issues a query request for each entity attribute to the token generation unit TGU. And performing a cryptographic determination on the access request of the subject according to the cryptographic policy returned by the policy generating unit PGU and the security attribute token AttToken returned by the token generating unit TGU, and sending the security decryption token DecToken of the determination result.
  • the resource decryption unit RDU After receiving the information of the resource decryption unit RDU, the policy decision unit PDU issues a policy query request to the policy generation unit PGU, and issues a query request for each entity attribute to the token generation unit TGU. And performing a cryptographic determination on the access request of the subject according to the cryptographic policy returned by the policy generating unit PGU and the security attribute token AttToken returned by the token generating unit TGU, and sending the security decryption token DecToken of the determination result.
  • Resource decryption processing The resource decryption unit RDU decrypts the encrypted resource according to the security decryption token DecToken returned by the policy determination unit PDU, and finally accesses the decrypted resource in a manner requested by the entity.
  • the cryptographic determination of the access request of the subject specifically refers to performing cryptographic determination using the security attribute token AttToken and the cryptographic policy CP, and outputting one for resources.
  • the decrypted secure decryption token DecToken if the access policy decision contained in the cryptographic policy is passed, the outputted DecToken is used as the secret information for recovering the key of the encrypted resource; otherwise, the output is an invalid random number.
  • the cryptographic attribute-based access control method and system are based on an attribute-based access control model, and the feature is that a cryptographic technique is introduced on the basis of the following:
  • PGU Policy Generation Unit
  • PAP Policy Management Point
  • TGU The token generation unit
  • PIP policy information point
  • the Policy Decision Unit is built on the Policy Decision Point (PDP), which is responsible for cryptographically determining the collected security attribute token and the cryptographic policy, and transmitting the determination result to the resource decryption unit.
  • PDP Policy Decision Point
  • the Resource Decryption Unit is built on a Policy Execution Point (PEP) for acquiring an encrypted object according to the access request of the subject, and calling the Policy Decision Unit PDU to perform an authorization decision, and receiving the decision from the policy determination unit. As a result, if the determination is passed, the decryption of the resource is performed and the corresponding access action is performed.
  • PEP Policy Execution Point
  • a method for constructing a cryptographic attribute based access control model employing the system, the method comprising:
  • System initialization call the system initialization Setup algorithm to generate the public key pk T and private key sk T of each entity, where T represents the entity name, the entity includes: the main body S, the object O, the action A, the environment E and the policy center P;
  • Resource Encryption Calling the Object Encryption Encrypt algorithm is used to encrypt the object, realizing the key escrow of the session key ek for encrypting the object on the policy center P; that is, applying the encryption algorithm to encrypt the object, the key For the session key ek, then encrypt the session key ek with the public key pk P of the policy center P; the resource encryption phase is used to implement the object storage module OSM;
  • Policy generation the policy selection is performed according to the current access request, and then the policy generation PolicyGen algorithm is invoked, and the cryptographic representation CP of the policy is generated by the entity public key pk T and the policy center P private key sk P ; the policy generation The stage is used to implement a build strategy generation unit PGU;
  • Token generation In the token generation phase, each entity obtains the attribute assignment attr in real time, and then calls the token to generate the TokenGen algorithm to generate a security token corresponding to the attribute assignment attr, that is, the security attribute token AttToken; the token generation phase is used for Implementing a build token generating unit TGU;
  • the policy decision unit PDU performs cryptographic determination based on the cryptographic policy CP and the security token AttToken of the attribute involved in the cryptographic policy, and outputs a secure decryption token DecToken for resource decryption;
  • the verification phase is used to implement the policy decision unit PD;
  • the system initializes the Setup algorithm by: specifying a specified security strength, generating a public key pk P and a private key sk P of the policy center P , and any entity T in ⁇ S, O, A, E ⁇ Public key pk T and private key sk T ;
  • the object encryption Encrypt algorithm is specifically: a public key pk P of a given policy center is generated, and a ciphertext C ek encrypted by the session key ek is generated, and the session key ek can be used to decrypt the encrypted resource;
  • the token generation TokenGen algorithm is specifically: a private key sk T of the given entity T, an attribute value attr, and a time-varying parameter t, generating a security token of the attribute attr, that is, a security attribute token AttToken;
  • the policy generation PolicyGen algorithm is specifically: giving the public key pk T of each entity T in ⁇ S, O, A, E ⁇ , the private key sk P of the policy center, the access policy ⁇ , the current time t, and the session key The ciphertext C ek , the cryptographic representation CP that generates the strategy ;;
  • the object decryption Decrypt algorithm is specifically: a ciphertext C ek of a given session key, a ciphertext CP of a policy ,, and a set of security attribute tokens AttToken corresponding to the attribute assignment, if and only if the attribute assignment satisfies the policy ,, The session key ek is recovered.
  • the dynamic rule-based cryptographic attribute-based access control method and system provided by the present invention has been separated from the traditional encryption system framework, and is a brand-new attribute base access supporting cryptography.
  • the control method and system can meet higher security requirements, have policy scalability and attribute assignment dynamics, and specific features include:
  • Each entity in the system dynamically issues attribute tokens according to functions
  • the access authorization is based on a dynamic security token (Token) instead of a user key
  • the attribute token is a cryptographically assigned attribute, that is, contains non-tamperable attribute value information, and also includes time-varying parameters. Such information ensures the unforgeability and instantaneous validity of the token.
  • the cryptographic attribute-based access control model of the present invention employs a large number of cryptographic techniques, including authorization hosting, object encryption, security tokens, and homomorphism. Passwords, hierarchical secret sharing, predicate encryption, and policy security decisions.
  • the cryptographic system constructed by the invention has the provable security and can have the semantic security under the selective plaintext attack when the enemy obtains a large number of tokens.
  • the cryptographic attribute-based access control method and system in the present invention supports policy scalability and dynamic acquisition of attribute tokens, and is a cryptographic solution of the existing ABAC system.
  • the solution can be widely used not only for sensitive data distribution in untrusted and open environments, rule-based authorization services, but also for secure sharing of private data between different security domains, such as grid computing, cloud computing, blockchain systems, Complex information systems such as social computing and mobile computing; can also be used to build an access control platform in a dynamic environment, which is the basic technology to ensure the security of all aspects of the system.
  • the cryptographic representation of the attribute is implemented using the security token; at the same time, the cryptographic representation of the policy is implemented using the promise of the policy; finally, the attribute-based password
  • the cryptographic representation of the learning representation and strategy represents the cryptographic decision to implement the access policy.
  • 1 is a structural block diagram of a cryptographic attribute based access control system based on dynamic rules
  • FIG. 2 is a flowchart of a cryptographic attribute based access control method based on dynamic rules
  • Embodiment 3 is an access control tree in Embodiment 3.
  • G 1 , G 2 and G T be multiplicative cyclic groups of three orders of prime p, element g is the generator of group G 1 , element h is the generator of G 2 ; then there is bilinear mapping And has the following properties:
  • a dynamic rule-based cryptographic attribute-based access control method includes four entity attribute sets, corresponding access policies, and an authorization process. For example, they will also be used in subsequent embodiments. :
  • the set of subject attributes S including: name and occupation, expressed as S 1 , S 2 .
  • the object attribute collection O including: file name and file type, expressed as O 1 , O 2 .
  • the action attribute set A includes: browsing and rewriting operations, denoted as A 1 , A 2 .
  • the set of environment attributes E including: time, expressed as E 1 .
  • This system consists of the following two rules:
  • Rule 1 The content of the rule is “Doctor can read the ward record at any time”, which is expressed as
  • Rule 2 The content of the rule is “The nurse can read the ward record on the working day”, which is expressed as
  • the access policy for “patient records” in hospitals is “doctors can read ward records at any time or nurses can read ward records on working days”, which is expressed as
  • the authorization process of the access policy is the process of attribute assignment and the process of Boolean logic determination. For example, there are two subjects in the system, doctor Zhang San and nurse Li Si.
  • the access control system based on the cryptographic attribute includes an encryption scheme, and an implementation of the scheme is as follows:
  • System initialization algorithm input is bilinear mapping system
  • the output is the public and private key pair of the policy center and each entity.
  • the session key ek encrypted for the object and the ciphertext C O that restores the key is the session key ek encrypted for the object and the ciphertext C O that restores the key.
  • the object is encrypted using the session key ek in any encryption method.
  • PolicyGen Policy generation algorithm
  • TokenGen The private key sk T and its attribute att input as the entity T ⁇ are output as the security token AttToken of the attribute att.
  • Resource decryption algorithm input as policy ⁇ and its ciphertext C P , all attribute token sets ⁇ AttToken ⁇ obtained from each entity, ciphertext C O of session key, output as session key ek .
  • the construction method is correct.
  • the authorization of the subject access resource is completed by calculating the following equation to restore the session key ek:
  • Step 3 of the ObjectDec algorithm
  • the specific calculation process of equation (7) is as follows:
  • the cryptographic scheme satisfies the following security properties:
  • the security token is used as the credential of the attribute. It is unforgeable under the time-varying parameter selection. That is, the attacker cannot forge a new valid token when obtaining a large number of valid tokens.
  • the cryptographic representation of the policy is related to the policy, and cannot be tampered once generated; and the cryptographic representation is bound to the request ciphertext and cannot be transferred to other ciphertexts; in addition, the cryptographic representation has Time-sensitive, can avoid replay attacks;
  • the decryption token is one secret at a time, and the valid token is indistinguishable from the random number, making the token unforgeable.
  • the session key has semantic security, ie the session key is indistinguishable from the random binary string.
  • This example takes the access policy in example 1 as an example to give a conversion process for generating a cryptographic representation of the policy.
  • This embodiment is also a detailed description of steps 2), 4) in the policy generation algorithm (PolicyGen), and step 2) in the resource decryption algorithm (ObjectDec).
  • An access strategy is composed of one or more predicates. As mentioned earlier, in a medical diagnostic recording system, the doctor “Zhang San” on Monday had to read the ward record. At this time, the access policy was set to “The doctor can read the ward record at any time or the nurse can read the ward record on the working day. ", the strategy can be formalized as:
  • Such access policies can be formalized as
  • the policy is visually represented as an access policy tree, as shown in Figure 3, where the root node t is the secret selected by the policy center P, see step 1) in PolicyGen, leaf nodes t 11 , t 121 , t 122 , t 2 , t 3 are the secrets of the predicates P 1 , P 2 , P 3 , P 4 and P 5 respectively, and s 1 , s 2 , s 3 , s 4 , s 5 are respectively P 1 , P 2 , P 3 , P 4 and P 5 selected random numbers, non-leaf nodes represent the "and" and "or" relationship between its child nodes.
  • the secret generation matrix M and the function ⁇ are generated by accessing the policy tree, see step 2) in PolicyGen. According to the markup on each attribute, a matrix M is constructed as follows:
  • M k denote the kth row of the matrix M
  • the dynamic rule-based cryptographic attribute-based access control method and system based on the invention has been separated from the traditional encryption system framework, and is a brand-new attribute-based access control method and system supporting cryptography, which can meet higher security.
  • Policy scalability and attribute assignment dynamics specific features include: no key or user private key, but use temporary attribute token for dynamic authorization; the owner uses the "system public key" to host access authorization;
  • the access control policy is dynamically generated by the search rule set and cryptographically; each entity in the system dynamically issues the attribute token according to the function; the access authorization and decryption of the encrypted data are obtained through the matching of the attribute token and the cryptographic access control.
  • the proposed system can be widely applied to sensitive data distribution in untrusted, open environments, rule-based authorization services, and secure sharing of private data between different security domains.

Abstract

本发明主要属于信息技术领域，具体涉及一种基于动态规则的密码学属性基访问控制方法与系统。在所述系统中受保护的客体以加密形式存储，只有满足属性基访问控制中访问策略要求的访问才能获得授权而解密客体，能够保证在不安全环境下的数据能够按照安全策略被授权访问，同时也支持策略可扩展与属性的动态获取。本发明所述基于动态规则的密码属性基访问控制方法与系统已经脱离传统的加密系统框架，是一种全新的支持密码学判定的属性基访问控制模型、方法和系统，可实现更加安全、多样、动态、灵活的访问授权，适用于大规模组织或信息系统，可以应用到诸如云计算、网格计算、分布式计算等环境。

Description

一种基于动态规则的密码学属性基访问控制方法与系统 技术领域
本发明主要属于信息技术领域，具体涉及一种基于动态规则的密码学属性基访问控制方法与系统。该方法和系统支持策略可扩展与属性动态获取的密码学访问，适用于大规模组织或信息系统，可以应用到诸如云计算、网格计算、分布式计算等环境。
背景技术
访问控制是保障信息系统安全的核心技术之一，它的任务是保证数字资产不被非法使用，通常指主体依据某些控制策略或权限对客体本身或是其资源进行的不同授权访问。
近年来，随着网络应用多样性、系统规模等的持续增长，一种被称为属性基访问控制(Attribute-based Access Control，ABAC)的新型访问控制技术被提出。它是利用相关实体(如主体、客体、动作、环境等)的属性(表示事物的某一性质与关系)作为授权的基础来实现访问控制，提供了更加灵活、动态、细粒度的授权控制，能够很好地适应这种开放的网络环境。
属性基访问控制是一种基于访问策略的细粒度、多因素访问控制方法。它包括四个实体，分别用S,O,A,E表示主体、客体、动作、环境的属性集合；每个属性集合包括若干属性，每个属性可被指定一个或多个属性值。属性可分为静态属性与动态属性两类，其中，环境属性通常是一类不同于主体、客体和动作的动态属性，如：访问时间、地点、设备、历史信息等，它的属性值获取具有动态、时变的特性。
属性基访问控制通过访问控制策略(简称访控策略，Policy)定义实体之间的授权关系，具体而言就，就是通过一系列规则(Rule)组成的策略来约束在环境E下主体S是否被允许以动作A访问对象O。进而，基于主体、客体、动作以及环境具有的属性值对访控策略进行判定，从而确定请求者的请求是否授权。属性的多样性、动态性、 以及访控策略的灵活性，使得ABAC具有足够的灵活性和可扩展性，同时，由于无需针对请求者的真实姓名进行策略判定，使得安全的匿名访问成为可能，这在开放环境下是十分重要的。
基于属性的访问控制模型包括以下基本功能模块，具体描述如下:
(1)策略管理点(Policy Administration Point,PAP)：负责创建访问策略，并对其进行有效的管理；
(2)策略信息点(Policy Information Point,PIP)：负责属性信息与实体的绑定，以及属性的创建与管理分发；
(3)策略执行点(Policy Enforcement Point,PEP)：负责处理访问请求，并执行由PDP返回的判定结果；
(4)策略判定点(Policy Decision Point,PDP)：负责对PEP发过来的访问请求进行策略判定。
随着网络共享与开放性的增强，信息系统的防护边界日益模糊乃至完全消失，建立在明确防御边界基础上的属性基访问控制方法已不能适应这种开放环境。
现有的ABAC模型都是非密码学化的，无论是访问策略的表示，实体属性赋值的表示，还是访问策略的判定都是非密码学化的，在没有可信(或安全)运行实体的开放环境下，这些非密码学表示都有可能被敌手攻击而被篡改和伪造，显然并不能保证访问判决正确性要求，也不能满足实时数据共享系统高安全强度的要求。因此，ABAC访问控制模型中属性赋值、策略、判定的密码学化是现有技术不能够解决的难点。
属性基加密(Attribute-based Encryption,ABE)技术的访问策略和密文相结合、属性赋值和用户密钥相结合，用户可以解密密文当且仅当用户私钥中的属性满足密文中的访问策略。但在这种ABE中，访问策略都是固定在密文中的、不可变更的，因此不具有可扩展性； 其次，属性赋值与密钥结合是固定不变的，不能持动态属性。
发明内容
针对上述技术问题，发明提出一种基于动态规则的密码学属性基访问控制方法与系统，是一种采用密码技术的属性基访问控制方法与系统。在该方法与系统中，受保护的客体被以加密形式存储，这意味着该客体被放置于开放、不安全环境下也不会被非授权访问，而只有满足属性基访问控制中策略要求的访问才能获得授权而解密客体，这就保证了在不安全环境下的数据能够按照安全策略被授权访问。
并且本发明所述方法与系统能够支持完整的属性基访问控制模型，并能够支持基于规则的、可扩展的密码化访问策略生成，以及支持动态的密码化属性获取。所述方法与系统使得主体对客体的授权访问过程高效、动态且安全，同时也保证了系统内访控规则的一致性和完整性。
本发明是通过以下技术方案实现的：
一种基于动态规则的密码学属性基访问控制系统，在所述系统中受保护的客体以加密形式存储，只有满足属性基访问控制中访问策略要求的访问才能获得授权而解密客体，其中，访问授权是建立在安全令牌Token基础上，能够保证在不安全环境下的数据能够按照安全策略被授权访问，同时也支持策略可扩展与属性的动态获取。
进一步地，所述系统包括三个存储模块和一个感知模块：
策略存储模块PSM：用于存储访问策略；
属性存储模块ASM：用于存储系统内各实体的属性以及属性赋值；
客体存储模块OSM：用于存储加密后的客体；
环境感知模块EPM：用于实时、动态地获取环境属性以及属性赋值；
所述系统还包括四个执行单元，具体如下：
策略生成单元PGU：该策略生成单元PGU从所述策略存储模块PSM中选取访问策略，生成访问策略的密码学表示CP，该访问策略的密码学表示CP即密码学化策略，将该密码学化策略提供给策略判定单元PDU；
令牌生成单元TGU：该令牌生成单元TGU从所述属性存储模块ASM和所述环境感知模块EPM中获取特定属性的属性赋值，并完成对该属性赋值的密码学表示，即安全属性令牌AttToken，最终将该安全属性令牌AttToken提供给策略判定单元PDU；
策略判定单元PDU：该策略判定单元PDU分别从所述策略生成单元PGU获得所述密码学化策略，从所述令牌生成单元TGU获得所述安全属性令牌AttToken，并对所述密码学化策略进行密码学判定，最后将判定结果信息，即安全解密令牌DecToken，提供给资源解密单元RDU；
资源解密单元RDU：该资源解密单元RDU根据所述策略判定单元PDU返回的所述安全解密令牌DecToken对资源进行解密，即，当且仅当所述策略判定单元PDU判定通过的情况下，资源解密单元RDU才能解密并恢复被加密资源。
进一步地，所述系统采用属性基访问控制模型ABAC，包括：实体属性集、访问策略和授权过程：
实体属性集：实体包括四个属性实体：主体、客体、动作、环境，并分别用(S,O,A,E)表示这四个实体的属性集合，以及策略中心P，用于管理安全策略；
访问策略：是指实体之间的授权关系，由若干规则构成，能将其转化布尔函数的形式，即，采用布尔函数F(x 1,x 2,…,x n)＝{True,False}描述所述实体属性集X∈{S,O,A,E}中的任意属性变量
Figure PCTCN2018074646-appb-000001
与访问许可True与拒绝False之间的逻辑关系；
授权过程：是从各个实体中获取属性值v 1,v 2,…,v n→x 1,x 2,…,x n， 并与已规定的访问策略相匹配，即对P(v 1,v 2,…,v n)进行估值并对访问是否授权进行判定的过程。
进一步地，所述访问策略由一个或者多个规则构成，所述规则具有与所述访问策略相同的语法结构，并通过布尔逻辑组合为策略；所述规则能够由属性变量为输入的布尔函数表示，布尔函数是通过作用在若干谓词上的布尔逻辑构成，每个谓词是一个作用在属性变量上的操作符构成的逻辑判定；其中，所述布尔逻辑包括与、或、非逻辑；所述操作符包括等于、大于、小于、属于、不属于、包含。
进一步地，所述安全属性令牌AttToken和所述安全解密令牌DecToken均属于安全令牌Token，所述安全令牌Token为临时性、不可伪造、公开可验证的数字证书，能够通过密码学验证方法来证明其有效性，所述系统中的访问授权建立在所述安全令牌Token基础上的；
其中，所述安全属性令牌AttToken：是属性赋值的密码化证书，即包含不可篡改的属性与属性值信息，也包括时变参数信息，保证令牌的不可伪造性和瞬时有效性；其中，所述时变参数信息包括随机数、计数值、时间戳；
所述安全解密令牌DecToken：是解密秘密的密码化证书，包含解密特定资源所需要的解密密钥的秘密信息及时变参数信息。
进一步地，客体是以加密形式存放，加密算法可以是任何对称加密算法与非对称加密算法；
进一步地，利用安全属性令牌代替了解密密钥，实现了分布式授权，且该令牌是公开可验证的；
进一步地，安全属性令牌是动态获取的，同一主体对同一客体在不同环境下的相同访问，策略判定结果可能不同；
进一步地，所述策略生成单元中的密码学化策略是动态生成的，允许实时改变密码学化策略并影响访问授权结果；
资源能否被解密是由所述策略判定单元确定的，当且仅当判定通过，资源才能被解密，主体才能访问客体；具体地，资源解密单元RDU解密并恢复被加密资源采用“二次解密”的形式：当且仅当策略判定单元PDU判定通过的情况下，资源解密单元RDU首先利用安全解密令牌DecToken解密出会话密钥ek，再用该会话密钥ek对资源进行解密。
进一步地，所述系统能够实现策略可扩展性与属性赋值动态性，策略可扩展性保证规则可以按照需求进行添加、修改或撤销，且这种改变可立刻对系统内(已加密)资源的访问授权产生影响；属性赋值动态性保证系统能够实时地获取到实体的当前属性。
一种基于动态规则的密码学属性基访问控制方法，所述方法采用所述系统，所述方法包括：
1)资源加密过程：客体以加密的形式存放在客体存储模块OSM中，并在属性存储模块ASM中记录该客体所具有的全部属性信息；
2)主体请求访问：某一主体发出对加密客体的访问请求，资源解密单元RDU接收请求，并调用策略判定单元PDU对该请求进行密码学判定；
3)访问授权判定：接收到所述资源解密单元RDU的信息之后，所述策略判定单元PDU分别向策略生成单元PGU发出策略查询请求，以及向令牌生成单元TGU发出各实体属性的查询请求，并根据所述策略生成单元PGU返回的密码学化策略以及所述令牌生成单元TGU返回的安全属性令牌AttToken对主体的访问请求进行密码学判定，并将判定结果的安全解密令牌DecToken发送回所述资源解密单元RDU；
4)资源解密处理：所述资源解密单元RDU根据所述策略判定单元PDU返回的所述安全解密令牌DecToken对加密资源进行解密，最后将解密后的资源以主体请求的方式予以访问。
进一步地，在访问授权判定过程中，所述对主体的访问请求进行密码学判定具体是指使用所述安全属性令牌AttToken与所述密码学化策略CP进行密码学判定，输出一个用于资源解密的安全解密令牌DecToken；如果所述密码学化策略所含的访问策略判定通过，输出的DecToken被用做恢复被加密资源的密钥的秘密信息，否则，输出的是一个无效随机数。
进一步地，所述密码学属性基访问控制方法及系统以属性基访问控制模型为基础，特征是在其基础上引入了密码技术，具体如下：
1)策略生成单元(PGU)构建在策略管理点(PAP)之上，该单元不仅负责策略的管理，而且用于实现策略的密码学化表示；
2)令牌生成单元(TGU)构建在策略信息点(PIP)之上，该单元不仅负责策略信息的收集，还包括生成属性对应的、公开可验证的安全令牌，包括策略中所涉及的所有实体属性，包括主体属性、客体属性、动作属性以及环境条件；
3)策略判定单元(PDU)构建在策略判定点(PDP)之上，该单元负责对收集到的安全属性令牌以及密码学化的策略进行密码学判定，并将判定结果发送给资源解密单元RDU；
4)资源解密单元(RDU)构建在策略执行点(PEP)之上，该单元用于根据主体的访问请求获取加密客体，并调用策略判定单元PDU进行授权判决，并接收来自策略判定单元的判定结果，如果判定通过，进行资源的解密并执行相应的访问动作。
一种密码学属性基访问控制模型的构造方法，所述方法采用所述系统，所述方法包括：
1)系统初始化：调用系统初始化Setup算法生成各个实体的公钥pk T和私钥sk T，其中，T表示实体名称，实体包括：主体S、客体O、动作A、环境E以及策略中心P；
2)资源加密：调用客体加密Encrypt算法用于对所述客体加密， 实现对用于加密客体的会话密钥ek在策略中心P上的密钥托管；即应用加密算法对客体进行加密，密钥为会话密钥ek，然后用策略中心P的公钥pk P对会话密钥ek进行加密；该资源加密阶段用于实现客体存储模块OSM；
3)策略生成：根据当前的访问请求进行策略Π的选择，再调用策略生成PolicyGen算法，通过实体公钥pk T与策略中心P私钥sk P共同生成策略Π的密码学表示CP；该策略生成阶段用于实现构建策略生成单元PGU；
4)令牌生成：该令牌生成阶段各实体实时获取属性赋值attr，再调用令牌生成TokenGen算法生成属性赋值attr对应的安全令牌，即安全属性令牌AttToken；该令牌生成阶段用于实现构建令牌生成单元TGU；
5)资源解密：该资源解密阶段将客体解密Decrypt算法分为二个步骤：
(1)策略验证：策略判定单元PDU根据密码学化策略CP和该密码学化策略中所涉及属性的安全令牌AttToken进行密码学判定，输出用于资源解密的安全解密令牌DecToken；该策略验证阶段用于实现策略判定单元PD；
(2)密钥恢复：如果所述安全解密令牌DecToken是有效的，那么恢复出会话密钥ek，并使用所述会话密钥ek解密加密客体并执行相应的动作；反之，无法恢复会话密钥ek，当前访问被拒绝；该密钥恢复阶段用于实现资源解密单元RDU。
进一步地，所述系统初始化Setup算法具体为：给定一个指定安全强度，生成策略中心P的公钥pk P和私钥sk P，以及在{S,O,A,E}中的任意实体T的公钥pk T和私钥sk T；
所述客体加密Encrypt算法具体为：给定策略中心的公钥pk P，生成会话密钥ek加密后的密文C ek，该会话密钥ek能够用于解密加 密的资源；
所述令牌生成TokenGen算法具体为：给定实体T的私钥sk T，属性值attr，以及时变参数t,生成属性attr的安全令牌，即安全属性令牌AttToken；
所述策略生成PolicyGen算法具体为：给定{S,O,A,E}中各实体T的公钥pk T，策略中心的私钥sk P，访问策略Π，当前时间t，以及会话密钥的密文C ek，生成策略Π的密码学表示CP；
所述客体解密Decrypt算法具体为：给定会话密钥的密文C ek，策略Π的密文CP，以及属性赋值对应的安全属性令牌AttToken集合，当且仅当属性赋值满足策略Π时，恢复出会话密钥ek。
本发明的有益技术效果：
(1)与现有的ABE技术相比较，本发明所提供的基于动态规则的密码属性基访问控制方法与系统已经脱离传统的加密系统框架，是一种全新的支持密码学判定的属性基访问控制方法及系统，能满足更高的安全性要求，具有策略可扩展性和属性赋值动态性，具体特点包括：
1)不存在密钥或用户私钥，而使用动态安全令牌(Token)进行动态授权；
2)资源拥有者通过“系统公钥”(被称为策略中心公钥)将访问授权进行托管；
3)由规则集合动态生成访控策略并进行密码学化；
4)每个系统内实体根据职能动态地进行属性令牌发放；
5)通过属性令牌与密码化访控策略的匹配获得对加密数据的访问授权并解密。
(2)在本发明中，访问授权是基于动态安全令牌(Token)而非用户 密钥，属性令牌是对属性赋值的密码化，即包含不可篡改的属性值信息，也包括时变参数等信息，保证令牌的不可伪造性和瞬时有效性。
(3)为了将密码学技术应用于现有的属性基访问控制模型，本发明的密码学属性基访问控制模型中采用了大量密码学技术，包括授权托管、客体加密、安全令牌、同态密码、层次秘密共享、谓词加密、以及策略安全判定等。通过上述技术的综合运用，本发明所构造密码系统具有可证明安全性，能够在敌手获得大量令牌情况下具有选择明文攻击下的语义安全性。
(4)本发明中的密码学化属性基访问控制方法及系统，支持策略可扩展和属性令牌的动态获取，是已有ABAC系统的密码学解决方案。该方案不仅可被广泛应用于不可信、开放环境下的敏感数据分发、基于规则的授权服务，以及不同安全域之间的隐私数据安全共享，比如网格计算、云计算、区块链系统、社会计算、移动计算等复杂信息系统；还可用于构建动态环境下的访控平台，是保证系统各环节安全的基本技术。
总之，在本发明所提密码学属性基访问控制方法与系统中，使用安全令牌实现了属性的密码学表示；同时，利用策略的承诺实现了策略的密码学表示；最后，基于属性的密码学表示和策略的密码学表示实现访问策略的密码学判定。本发明为实现更为精细的、实时的、安全的、大规模的隐私数据共享成为可能。
附图说明
图1是基于动态规则的密码学属性基访问控制系统结构框图；
图2是基于动态规则的密码学属性基访问控制方法的流程图；
图3是实施例3中的访问控制树。
具体实施方式
为了使本发明的目的、技术方案及优点更加清楚明白，以下结合附图及实施例，对本发明进行进一步详细描述。应当理解，此处所描述的具体实施例仅仅用于解释本发明，并不用于限定本发明。
相反，本发明涵盖任何由权利要求定义的在本发明的精髓和范围上做的替代、修改、等效方法以及方案。进一步，为了使公众对本发明有更好的了解，在下文对本发明的细节描述中，详尽描述了一些特定的细节部分。对本领域技术人员来说没有这些细节部分的描述也可以完全理解本发明。
在实施例中，将采用常见的双线性对(Bilinear Pairing)进行构造，具体定义如下：
令G 1,G 2和G T是三个阶为素数p的乘法循环群，元素g是群G 1的生成元，元素h是G 2的生成元；那么就有双线性映射
Figure PCTCN2018074646-appb-000002
且具有以下性质：
1)双线性：对任意的a,b属于
Figure PCTCN2018074646-appb-000003
使得e(g a,h b)＝e(g,h) ab；
2)非退化性：e(g,h)≠1；
3)可计算性：存在多项式时间内算法可快速计算e(g,h)。
令该双线性映射系统表示为
Figure PCTCN2018074646-appb-000004
实施例1
一种基于动态规则的密码学属性基访问控制方法，本实施例中，所述方法包括四个实体属性集合、相应的访问策略以及授权过程，具体实施例如下，它们也将用于后续实施例：
主体属性集合S，包括：姓名和职业，表示为S 1,S 2。姓名以字符串表示，如包含两名成员{"ZhangSan","LiSi"}，将其形式化命名为S 1:＝{s 11,s 12}。职业包括两个属性值{Doctor,Nurse}，将其形式化命名为S 2:＝{s 21,s 22}。
客体属性集合O，包括：文件名和文件类型，表示为O 1,O 2。文件名是字符串，形式化表示为O 1:＝{0,1} n。文件类型包括“病房记录” 与“患者档案”两个属性值{WardRecord,PatientArchive}，将其形式化命名为O 2＝{o 21,o 22}。
动作属性集合A，包括：浏览和改写操作，表示为A 1,A 2。浏览操作有两个属性值{Read,Retrieval}，将其形式化命名为A 1:＝{a 11,a 12}；改写操作有两个属性值{Write,Append}，将其形式化命名为A 2＝{a 21,a 22}。
环境属性集合E，包括：时间，表示为E 1。时间有两个属性值{Weekday,Weekend}分别表示工作日和双休日，形式化命名为E 1＝{e 11,e 12}。
此系统中包含以下两条规则构成：
规则一：规则内容为“医生可以在任何时间读病房记录”，形式化表示为
Figure PCTCN2018074646-appb-000005
规则二：规则内容为“护士可以在工作日读病房记录”,形式化表示为
Figure PCTCN2018074646-appb-000006
根据上述规则，对于医院中“病房记录”的访问策略为“医生可以在任何时间读病房记录或者护士可以在工作日读病房记录”，形式化表示为
Figure PCTCN2018074646-appb-000007
该访问策略的授权过程就是属性赋值的带入和布尔逻辑判定过程，例如，系统中有两个主体，医生张三和护士李四。
如果张三在工作日申请读病房记录，他的属性赋值集合为(S 1,S 2,O 2,A 1,E 1)←(s 11,s 21,o 21,a 11,e 11)，带入到∏，则返回True，允许授权；
相反，李四在双休日申请访问病房记录，他的属性赋值集合为(S 1,S 2,O 2,A 1,E 1)←(s 12,s 22,o 21,a 11,e 12)，带入到∏，则返回False，拒绝授 权。
实施例2
基于所述密码学属性基访问控制系统包含一个加密方案，该方案的一个实施例如下：
1.系统初始化算法(Setup)：输入为双线性映射系统
Figure PCTCN2018074646-appb-000008
输出为策略中心和各实体的公私密钥对。
1)在G 1,G 2群上分别随机选择生成元g和h；
2)在
Figure PCTCN2018074646-appb-000009
域随机选取秘密指数α，计算g α；
3)输出策略中心P的公/私密钥对为pk P＝(g,h,g α)和sk P＝(α)；
4)对于实体集合Ω＝{S,O,A,E}中的每个实体T∈Ω，在
Figure PCTCN2018074646-appb-000010
域随机选取秘密指数β T，计算
Figure PCTCN2018074646-appb-000011
5)输出实体T的公/私密钥对为
Figure PCTCN2018074646-appb-000012
和sk T＝(β T)对
Figure PCTCN2018074646-appb-000013
2.客体加密算法(ObjectEnc)：输入为策略中心P的公钥pk p，输出
为客体加密的会话密钥ek和恢复该密钥的密文C O。
1)在
Figure PCTCN2018074646-appb-000014
域随机选取秘密指数w；
2)随机选择会话密钥ek∈{0,1} |p|；
3)计算g w和
Figure PCTCN2018074646-appb-000015
4)生成密文
Figure PCTCN2018074646-appb-000016
5)在任何加密方法中利用会话密钥ek对客体加密。
3.策略生成算法(PolicyGen)：输入为访问策略∏、密文C O、以及策略中心P的私钥sk p，输出为策略∏的密文C P。
1)在
Figure PCTCN2018074646-appb-000017
域随机选取秘密指数t，计算
Figure PCTCN2018074646-appb-000018
2)按照实施例3中办法将访问策略∏转化为(M,π)，其中，M为l×n秘密生成矩阵，l为策略中逻辑判定项的数目；
3)在
Figure PCTCN2018074646-appb-000019
域中随机选择n-1个秘密y i，并设定v＝(t,y 2,...,y n) T，其中，i的取值为2到n；
4)计算λ k＝M k·v，其中，M k为秘密生成矩阵M的第k行，k的取值为1到l；
5)对于k＝1到l，在
Figure PCTCN2018074646-appb-000020
域随机选取r k，获取当前时间τ，并计算p k＝(p k1,p k2)，其中，
Figure PCTCN2018074646-appb-000021
6)输出策略的密文
Figure PCTCN2018074646-appb-000022
4.令牌生成算法(TokenGen)：输入为实体T∈Ω的私钥sk T及其属性att，输出为属性att的安全令牌AttToken。
1)计算属性att的哈希值H(att)；
2)获取时变参数τ(与策略生成中时间保持一致)；
3)计算并输出属性att的安全令牌为
Figure PCTCN2018074646-appb-000023
5.资源解密算法(ObjectDec)：输入为策略∏及其密文C P，从各实体中获取的所有属性令牌集合{AttToken}，会话密钥的密文C O，输出为会话密钥ek。
1)对于k＝1到l，对相同属性att下的策略密文p k＝(p k1,p k2)与安全属性令牌AttToken计算
Figure PCTCN2018074646-appb-000024
2)根据矩阵M和I＝{i:π(i)∈U}，按照实施例3中办法计算常数集合
Figure PCTCN2018074646-appb-000025
得到安全解密令牌
Figure PCTCN2018074646-appb-000026
3)通过计算下面等式恢复ek：
Figure PCTCN2018074646-appb-000027
4)利用恢复的会话密钥ek对资源进行解密。
方案的正确性说明：
所述构造方法是正确的，对于满足访问策略的会话，通过计算以 下等式恢复会话密钥ek来完成对主体访问资源的授权：
ObjectDec算法步骤1)中式(5)具体计算过程如下：
Figure PCTCN2018074646-appb-000028
ObjectDec算法步骤2)中式(6)具体计算过程如下：
Figure PCTCN2018074646-appb-000029
ObjectDec算法步骤3)中式(7)具体计算过程如下：
Figure PCTCN2018074646-appb-000030
方案的安全性说明：
所述密码学方案满足如下安全性质：
1.安全令牌作为属性的凭证，在选择时变参数下是存在性不可伪造的，也就是，攻击者在获得大量有效令牌情况下，依然无法伪造出新的有效令牌；
2.策略的密码学表示是与策略∏相关的，一旦生成后不可篡改；且该密码学表示是与请求密文绑定的，不能将其转移到其它密文；此外，该密码学表示具有时效性的，可以避免重放攻击；
3.解密令牌是一次一密的，有效令牌与随机数不可区分，使得该令牌具有不可伪造性。
4.会话密钥具有语义安全性，即会话密钥与随机二进制串不可区分。
实施例3
本实例以实例1中的访问策略∏为例，给出生成策略∏的密码学 表示的转化过程。该实施例也是对策略生成算法(PolicyGen)中步骤2)，4)，资源解密算法(ObjectDec)中步骤2)的详细说明。
访问策略∏是由一个或者多个谓词构成的。如前所述，在一个医疗诊断记录系统中，周一医生“张三”要读取病房记录，此时访问策略设定为“医生可以在任何时间读病房记录或者护士可以在工作日读病房记录”，该策略可形式化表示为：
∏:＝(S 2＝s 21∧O 2＝o 21∧A 1＝a 11)∨(S 2＝s 22∧O 2＝o 21∧A 1＝a 11∧E 1＝e 11)  (11)
将此访问策略形式化描述为下述访问矩阵：
Figure PCTCN2018074646-appb-000031
其中P 1…P 5分别表示谓词S 2＝s 21、S 2＝s 22、E 1＝e 11、O 2＝o 21以及A 1＝a 11。这样访问策略可以形式化表示为
(P 1∧P 4∧P 5)∨(P 2∧P 3∧P 4∧P 5)＝(P 1∨(P 2∧P 3))∧P 4∧P 5     (13)
令函数π表示由A中i列到P i的映射，即π(i)＝P i。此外，该策略存在两个授权集合，分别为U 1＝{P 1,P 4,P 5}和U 2＝{P 2,P 3,P 4,P 5}。
将该策略形象地表示为一棵访问策略树，如图3所示，其中，根节点t为策略中心P选择的秘密，见PolicyGen中步骤1)，叶子节点t 11,t 121,t 122,t 2,t 3分别为谓词P 1，P 2，P 3，P 4及P 5各自拥有的秘密，s 1,s 2,s 3,s 4,s 5分别为P 1，P 2，P 3，P 4及P 5选取的随机数，非叶子节点表示它的子节点之间的“与”和“或”关系。下一步，通过访问策略树生成秘密生成矩阵M和函数π，见PolicyGen中步骤2)。根据每个属性上的标记，矩阵M一种构造如下所示：
Figure PCTCN2018074646-appb-000032
在这个例子中，如PolicyGen中步骤3)设定v＝(t,y 2,...,y n) T，根据计算可得M·v＝(t 11,t 121,t 122,t 2,t 3) T。令M k表示矩阵M的第k行，那么λ k＝M k·v是P k的秘密，见PolicyGen中步骤4)，即
(λ 1,λ 2,λ 3,λ 4,λ 5) T＝(t 11,t 121,t 122,t 2,t 3) T      (15)
对于解密算法，因为U 1＝{P 1,P 4,P 5}是一个授权集合，令I＝{i:π(i)∈U 1}＝{1,4,5}，为计算得到常数集合
Figure PCTCN2018074646-appb-000033
即常量ω 1，ω 4和ω 5，令
ω 1M 1+ω 4M 4+ω 5M 5＝(1 0 0 0)         (16)
带入M 1，M 4和M 5，可以得到
Figure PCTCN2018074646-appb-000034
通过计算可得到常量ω 1，ω 4和ω 5：
Figure PCTCN2018074646-appb-000035
因为
Figure PCTCN2018074646-appb-000036
和v＝(t,y 2,...,y n) T，通过下式恢复共享秘密t：
Figure PCTCN2018074646-appb-000037
随后计算
Figure PCTCN2018074646-appb-000038
利用
Figure PCTCN2018074646-appb-000039
恢复会话密钥ek。最后，医生“张三”就可以利用恢复出的会话密钥ek解密病房记录并读取其中的相关内容。
本发明所推荐基于动态规则的密码学属性基访问控制方法与系统已经脱离传统的加密系统框架，是一种全新的支持密码学判定的属性基访问控制方法和系统，能满足更高的安全性要求：策略可扩展性和属性赋值动态性，具体特点包括：不存在密钥或用户私钥，而使用临时性属性令牌进行动态授权；所有者通过“系统公钥”将访问授权进行托管；通过查找规则集动态生成访控策略并进行密码化；每个系统内实体根据职能动态地进行属性令牌发放；通过属性令牌与密码化访问控制的匹配获得对加密数据的访问授权并解密。所提系统可被广泛应用于不可信、开放环境下的敏感数据分发、基于规则的授权服务，以及不同安全域之间的隐私数据安全共享。

Claims (10)

  1. 一种基于动态规则的密码学属性基访问控制系统，其特征在于，在所述系统中受保护的客体以加密形式存储，只有满足属性基访问控制中访问策略要求的访问才能获得授权而解密客体，其中，访问授权是建立在安全令牌Token基础上，能够保证在不安全环境下的数据能够按照访问策略被授权访问，同时也支持策略可扩展与属性的动态获取。
  2. 根据权利要求1所述一种基于动态规则的密码学属性基访问控制系统，其特征在于，
    所述系统包括三个存储模块和一个感知模块：
    策略存储模块PSM：用于存储访问策略；
    属性存储模块ASM：用于存储系统内各实体的属性以及属性赋值；
    客体存储模块OSM：用于存储加密后的客体；
    环境感知模块EPM：用于实时、动态地获取环境属性以及属性赋值；
    所述系统还包括四个执行单元，具体如下：
    策略生成单元PGU：该策略生成单元PGU从所述策略存储模块PSM中选取访问策略，生成访问策略的密码学表示CP，即密码学化策略，将该密码学化策略提供给策略判定单元PDU；
    令牌生成单元TGU：该令牌生成单元TGU从所述属性存储模块ASM和所述环境感知模块EPM中获取特定属性的属性赋值，并完成对该属性赋值的密码学表示，即安全属性令牌AttToken，最终将该安全属性令牌AttToken提供给策略判定单元PDU；
    策略判定单元PDU：该策略判定单元PDU分别从所述策略生成单元PGU获得所述密码学化策略，从所述令牌生成单元TGU获得所述安全属性令牌AttToken，并对所述密码学化策略进行密码学判定，最后将判定结果信息，即安全解密令牌DecToken，提供给资源解密 单元RDU；
    资源解密单元RDU：该资源解密单元RDU根据所述策略判定单元PDU返回的所述安全解密令牌DecToken对资源进行解密，即，当且仅当所述策略判定单元PDU判定通过的情况下，资源解密单元RDU才能解密并恢复被加密资源。
  3. 根据权利要求1所述一种基于动态规则的密码学属性基访问控制系统，其特征在于，所述系统采用属性基访问控制模型ABAC，包括：实体属性集、访问策略和授权过程：
    实体属性集：实体包括四个属性实体：主体、客体、动作、环境，并分别用S,O,A,E表示这四个实体的属性集合；还包括策略中心P，用于管理安全策略；
    访问策略：是指实体之间的授权关系，由若干规则构成，能将访问策略转化布尔函数的形式，即，采用布尔函数F(x 1,x 2,…,x n)＝{True,False}描述所述实体属性集X∈{S,O,A,E}中的任意属性变量x i∈X与访问许可True与拒绝False之间的逻辑关系；
    授权过程：是从各个实体中获取属性值v 1,v 2,…,v n→x 1,x 2,…,x n，并与已规定的访问策略相匹配，即对P(v 1,v 2,…,v n)进行估值并对访问是否授权进行判定的过程。
  4. 根据权利要求3所述一种基于动态规则的密码学属性基访问控制系统，其特征在于，所述访问策略由一个或者多个规则构成，所述规则具有与所述访问策略相同的语法结构，并通过布尔逻辑组合为策略；所述规则能够由属性变量为输入的布尔函数表示，布尔函数是通过作用在若干谓词上的布尔逻辑构成，每个谓词是一个作用在属性变量上的操作符构成的逻辑判定；其中，所述布尔逻辑包括与、或、非逻辑；所述操作符包括等于、大于、小于、属于、不属于、包含。
  5. 根据权利要求2所述基于动态规则的密码学属性基访问控制系 统，其特征在于，所述安全属性令牌AttToken和所述安全解密令牌DecToken均属于安全令牌Token，所述安全令牌Token为临时性、不可伪造、公开可验证的数字证书，能够通过密码学验证方法来证明其有效性，所述系统中的访问授权建立在所述安全令牌Token基础上的；
    其中，所述安全属性令牌Token：是属性赋值的密码化证书，即包含不可篡改的属性与属性值信息，也包括时变参数信息，保证令牌的不可伪造性和瞬时有效性；其中，所述时变参数信息包括随机数、计数值、时间戳；
    所述安全解密令牌DecToken：是解密秘密的密码化证书，包含解密特定资源所需要的解密密钥的秘密信息及时变参数信息。
  6. 根据权利要求1所述基于动态规则的密码学属性基访问控制系统，其特征在于，
    客体是以加密形式存放，加密算法可以是任何对称加密算法与非对称加密算法；
    利用安全属性令牌代替了解密密钥，实现了分布式授权，且该安全属性令牌是公开可验证的；
    所述安全属性令牌是动态获取的，同一主体对同一客体在不同环境下的相同访问，策略判定结果可能不同；
    所述策略生成单元中的密码学化策略是动态生成的，允许实时改变密码学化策略并影响访问授权结果；
    资源能否被解密是由所述策略判定单元确定的，当且仅当判定通过，资源才能被解密，主体才能访问客体。
  7. 一种基于动态规则的密码学属性基访问控制方法，所述方法采用权利要求1-6任一项所述系统，其特征在于，所述方法包括：
    1)资源加密过程：客体以加密的形式存放在客体存储模块OSM中，并在属性存储模块ASM中记录该客体所具有的全部属性信息；
    2)主体请求访问：某一主体发出对加密客体的访问请求，资源解密单元RDU接收请求，并调用策略判定单元PDU对该请求进行密码学判定；
    3)访问授权判定：接收到所述资源解密单元RDU的信息之后，所述策略判定单元PDU分别向策略生成单元PGU发出策略查询请求，以及向令牌生成单元TGU发出各实体属性的查询请求，并根据所述策略生成单元PGU返回的密码学化策略以及所述令牌生成单元TGU返回的安全属性令牌AttToken对主体的访问请求进行密码学判定，并将判定结果及安全解密令牌DecToken发送回所述资源解密单元RDU；
    4)资源解密处理：所述资源解密单元RDU根据所述策略判定单元PDU返回的所述安全解密令牌DecToken对加密资源进行解密，最后将解密后的资源以主体请求的方式予以访问。
  8. 根据权利要求7所述基于动态规则的密码学属性基访问控制方法，其特征在于，在访问授权判定过程中，所述对主体的访问请求进行密码学判定具体是指使用所述安全属性令牌AttToken与所述密码学化策略CP进行密码学判定，输出一个用于资源解密的安全解密令牌DecToken；如果所述密码学化策略所含的访问策略判定通过，输出的DecToken被用做恢复被加密资源的密钥的秘密信息，否则，输出的是一个无效随机数。
  9. 一种密码学属性基访问控制模型的构造方法，所述方法采用权利要求1-6任一项所述系统，其特征在于，所述方法包括：
    1)系统初始化：调用系统初始化Setup算法生成各个实体的公钥pk T和私钥sk T，其中，T表示实体名称，实体包括：主体S、客体O、动作A、环境E以及策略中心P；
    2)资源加密：调用客体加密Encrypt算法用于对所述客体加密，实现对用于加密客体的会话密钥ek在策略中心P上的密钥托 管；即应用加密算法对客体进行加密，密钥为会话密钥ek，然后用策略中心P的公钥pk P对会话密钥ek进行加密；该资源加密阶段用于实现客体存储模块OSM；
    3)策略生成：根据当前的访问请求进行策略Π的选择，再调用策略生成PolicyGen算法，通过实体公钥pk T与策略中心P私钥sk P共同生成策略Π的密码学表示CP；该策略生成阶段用于实现策略生成单元PGU；
    4)令牌生成：该令牌生成阶段各实体实时获取属性赋值attr，再调用令牌生成TokenGen算法生成属性赋值attr对应的安全令牌，即安全属性令牌AttToken；该令牌生成阶段用于实现令牌生成单元TGU；
    5)资源解密：该资源解密阶段将客体解密Decrypt算法分为二个步骤：
    (1)策略验证：策略判定单元PDU根据密码学化策略CP和该密码学化策略中所涉及属性的安全属性令牌AttToken进行密码学判定，输出用于资源解密的安全解密令牌DecToken；该策略验证阶段用于实现策略判定单元PDU；
    (2)密钥恢复：如果所述安全解密令牌DecToken是有效的，那么恢复出会话密钥ek，并使用所述会话密钥ek解密加密客体并执行相应的动作；反之，无法恢复会话密钥ek，当前访问被拒绝；该密钥恢复阶段用于实现资源解密单元RDU。
  10. 根据权利要求9所述一种密码学属性基访问控制模型的构造方法，其特征在于，
    所述系统初始化Setup算法具体为：给定一个指定安全强度，生成策略中心P的公钥pk P和私钥sk P，以及在{S,O,A,E}中的任意实体T的公钥pk T和私钥sk T；
    所述客体加密Encrypt算法具体为：给定策略中心的公钥pk P， 生成会话密钥ek加密后的密文C ek，该会话密钥ek能够用于解密加密的资源；
    所述令牌生成TokenGen算法具体为：给定实体T的私钥sk T，属性值attr，以及时变参数t,生成属性attr的安全令牌，即安全属性令牌AttToken；
    所述策略生成PolicyGen算法具体为：给定{S,O,A,E}中各实体T的公钥pk T，策略中心的私钥sk P，访问策略Π，当前时间t，以及会话密钥的密文C ek，生成策略Π的密码学表示CP；
    所述客体解密Decrypt算法具体为：给定会话密钥的密文C ek，策略Π的密文CP，以及属性赋值对应的安全属性令牌AttToken集合，当且仅当属性赋值满足策略Π时，恢复出会话密钥ek。
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Cited By (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN111970106A (zh) * 2020-08-19 2020-11-20 北京邮电大学 一种格上支持全同态的短密文属性基加密方法及系统
CN113704795A (zh) * 2021-09-02 2021-11-26 杭州戎戍网络安全技术有限公司 一种基于标签属性的多域访问控制形式化建模方法
CN113904818A (zh) * 2021-09-27 2022-01-07 九江学院 一种支持密文共享和汇聚的轻量级细粒度访问控制方法
CN115567247A (zh) * 2022-08-31 2023-01-03 西安电子科技大学 一种去中心化的多权威隐私保护数据访问控制方法及系统

Families Citing this family (27)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN112425115B (zh) * 2018-04-26 2024-04-16 塞克罗斯股份有限公司 匿名系统中的多因素访问控制方法
CN108647523B (zh) * 2018-04-28 2020-01-17 华南理工大学 一种基于区块链的电子证明系统及存证、文件恢复方法
US10839069B2 (en) * 2018-07-10 2020-11-17 Microsoft Technology Licensing, Llc Protecting artificial intelligence models using virtual secure mode
US11310041B2 (en) * 2019-04-05 2022-04-19 Arizona Board Of Regents On Behalf Of Arizona State University Method and apparatus for achieving fine-grained access control with discretionary user revocation over cloud data
CN110474893B (zh) * 2019-07-30 2021-10-08 同济大学 一种异构跨信任域密态数据安全分享方法及系统
US11539517B2 (en) * 2019-09-09 2022-12-27 Cisco Technology, Inc. Private association of customer information across subscribers
CN110784316B (zh) * 2019-10-29 2023-04-07 安徽大学 一种基于策略隐藏的自适应策略更新快速属性加密方法
CN110890961B (zh) * 2019-12-11 2023-02-03 赣南师范大学 一种新型安全高效的多授权属性基密钥协商协议
CN111400750B (zh) * 2020-03-11 2023-05-30 北京天琴合创技术有限公司 基于访问过程判定的可信度量方法和装置
US11223487B2 (en) * 2020-03-19 2022-01-11 Jinan University Method and system for secure blockchain-based vehicular digital forensics
CN111669386B (zh) * 2020-05-29 2021-06-04 武汉理工大学 一种基于令牌且支持客体属性的访问控制方法及装置
CN112711767B (zh) * 2021-01-13 2023-12-22 湖南大学 一种可验证且隐私保护的支持向量机分类方法
CN117063174A (zh) * 2021-02-10 2023-11-14 V-Key公司 用于通过基于app的身份的app间相互信任的安全模块及方法
CN113507359A (zh) * 2021-06-18 2021-10-15 泰安北航科技园信息科技有限公司 基于区块链的数字版权多权限属性加密管理系统
CN113987465B (zh) * 2021-08-18 2022-05-17 齐鲁工业大学 一种海量异构物联网设备的通用精准访问控制系统及方法
CN113949541B (zh) * 2021-09-30 2022-10-11 南京航空航天大学 一种基于属性策略的dds安全通信中间件设计方法
CN114268482A (zh) * 2021-12-15 2022-04-01 北京工业大学 一种基于属性布隆过滤器的快速策略检索方法
CN114257446B (zh) * 2021-12-20 2023-05-23 湖北工业大学 基于可搜索加密的数据访问控制方法、计算机设备
CN114513533B (zh) * 2021-12-24 2023-06-27 北京理工大学 一种分类分级健身健康大数据共享系统及方法
CN115001730B (zh) * 2022-03-02 2023-09-05 上海交通大学 分布式场景下基于角色属性的访问控制系统及方法
CN114567500A (zh) * 2022-03-04 2022-05-31 南京联成科技发展股份有限公司 一种集中管控中心传输数据的加密方法
CN114978578B (zh) * 2022-04-06 2023-09-19 中债金科信息技术有限公司 基于属性密钥派生的数据越权访问控制方法及装置
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CN114745114B (zh) * 2022-04-25 2022-11-08 四川凝思软件有限公司 基于口令派生的密钥协商方法、装置、设备及介质
CN115051839B (zh) * 2022-05-25 2024-01-09 东南大学 一种基于kp-abe的dds访问控制和加解密系统及方法
US20240121081A1 (en) * 2022-10-10 2024-04-11 Microsoft Technology Licensing, Llc Access control using mediated location, attribute, policy, and purpose verification
CN116052832B (zh) * 2023-04-03 2023-06-30 青岛市妇女儿童医院（青岛市妇幼保健院、青岛市残疾儿童医疗康复中心、青岛市新生儿疾病筛查中心） 一种基于医疗信息的防篡改传输方法

Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN103327002A (zh) * 2013-03-06 2013-09-25 西安电子科技大学 基于属性的云存储访问控制系统
CN104901942A (zh) * 2015-03-10 2015-09-09 重庆邮电大学 一种基于属性加密的分布式访问控制方法
CN106059763A (zh) * 2016-07-29 2016-10-26 南京邮电大学 云环境下属性基多机构层次化密文策略权重加密方法
US20170126687A1 (en) * 2014-09-05 2017-05-04 Axiomatics Ab Provisioning system-level permissions using attribute-based access control policies

Family Cites Families (9)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
GB2523331A (en) * 2014-02-20 2015-08-26 Ibm Attribute-based access control
CN104683362B (zh) * 2015-03-27 2017-05-17 合肥工业大学 一种细粒度隐私安全的访问控制系统及其访问控制方法
CN105245554B (zh) * 2015-11-24 2018-04-10 无锡江南计算技术研究所 一种云环境下的动态属性访问控制方法
US10235176B2 (en) * 2015-12-17 2019-03-19 The Charles Stark Draper Laboratory, Inc. Techniques for metadata processing
US10936713B2 (en) * 2015-12-17 2021-03-02 The Charles Stark Draper Laboratory, Inc. Techniques for metadata processing
CN105635135B (zh) * 2015-12-28 2019-01-25 北京科技大学 一种基于属性集及关系谓词的加密系统及访问控制方法
US10523437B2 (en) * 2016-01-27 2019-12-31 Lg Electronics Inc. System and method for authentication of things
CN105991278B (zh) * 2016-07-11 2019-06-28 河北省科学院应用数学研究所 一种基于cp-abe的密文访问控制方法
SG11202007272QA (en) * 2018-02-02 2020-08-28 Charles Stark Draper Laboratory Inc Systems and methods for policy execution processing

Patent Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN103327002A (zh) * 2013-03-06 2013-09-25 西安电子科技大学 基于属性的云存储访问控制系统
US20170126687A1 (en) * 2014-09-05 2017-05-04 Axiomatics Ab Provisioning system-level permissions using attribute-based access control policies
CN104901942A (zh) * 2015-03-10 2015-09-09 重庆邮电大学 一种基于属性加密的分布式访问控制方法
CN106059763A (zh) * 2016-07-29 2016-10-26 南京邮电大学 云环境下属性基多机构层次化密文策略权重加密方法

Cited By (8)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN111970106A (zh) * 2020-08-19 2020-11-20 北京邮电大学 一种格上支持全同态的短密文属性基加密方法及系统
CN111970106B (zh) * 2020-08-19 2021-11-05 北京邮电大学 一种格上支持全同态的短密文属性基加密方法及系统
CN113704795A (zh) * 2021-09-02 2021-11-26 杭州戎戍网络安全技术有限公司 一种基于标签属性的多域访问控制形式化建模方法
CN113704795B (zh) * 2021-09-02 2024-02-06 杭州戎戍网络安全技术有限公司 一种基于标签属性的多域访问控制形式化建模方法
CN113904818A (zh) * 2021-09-27 2022-01-07 九江学院 一种支持密文共享和汇聚的轻量级细粒度访问控制方法
CN113904818B (zh) * 2021-09-27 2023-04-18 九江学院 一种支持密文共享和汇聚的轻量级细粒度访问控制方法
CN115567247A (zh) * 2022-08-31 2023-01-03 西安电子科技大学 一种去中心化的多权威隐私保护数据访问控制方法及系统
CN115567247B (zh) * 2022-08-31 2024-03-19 西安电子科技大学 一种去中心化的多权威隐私保护数据访问控制方法及系统

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