Revocation Capability Research Articles

Delegated Anonymous Credentials With Revocation Capability for IoT Service Chains (DANCIS)

This article deals with providing privacy-preserving access control in Internet of Things (IoT) systems. Here, a user/IoT device requests access to services provided by other IoT devices and multiple requests are combined to a request-specific service chain. An anonymous delegated credential-based system architecture is proposed, where the requester’s identity is not exposed to the services. The article presents the proposed architecture’s various components including the security aspects. Various options for implementing the architecture on resource-full and resource-constrained services are presented. A prototype of the proposed architecture is then implemented using Linux-based containers to emulate the services. Two representative systems, namely, a small-scale home automation system using a short service chain and a large-scale industrial automation system using a long service chain are considered. Timing measurements from the implementation are presented to demonstrate that the architecture is feasible and can be adapted for practical use in large-scale IoT systems.

Indirect Revocable KP-ABE With Revocation Undoing Resistance

Lately, many cloud-based applications proposed attribute-based encryption (ABE) as an all-in-one solution for achieving confidentiality and access control. Within this paradigm, data producers store the encrypted data on a semi-trusted cloud server, and users, holding decryption keys issued by a key authority, can decrypt data according to some access control policy. To be used in practical cases, any ABE scheme should implement a key revocation mechanism which assures that a compromised decryption key cannot be used anymore to decrypt data. Yu <italic xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">et al.</i> (2010) introduced an ABE scheme with revocation capabilities that enjoys several unique advantages, such as reactivity and efficiency. In the scheme, the cloud server is entitled to update keys and ciphertexts in order to achieve revocation. Unfortunately, the cloud server retains the power to undo the revocation of a key (revocation undoing attack) so endangering confidentiality. In this article, we propose a revocable ABE scheme that still ensures the advantages of Yu <italic xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">et al.</i> ’s scheme, but it also resists to the revocation undoing attack. We formally prove the security of our scheme and show through simulations that the user experiences a slightly higher computational cost with respect to Yu <italic xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">et al.</i> ’s scheme.

CrypSH: A Novel IoT Data Protection Scheme Based on BGN Cryptosystem

The Internet of Things (IoT) is an emerging paradigm and has penetrated deeply into our daily life. Due to the seamless connections of the IoT devices with the physical world through the Internet, the IoT applications use the cloud to store and provide ubiquitous access to collected data. Sharing of data with third party services and other users incurs potential risks and leads to unique security and privacy concerns, e.g., data breaches. Existing cryptographic solutions are inapt for resource-constrained IoT devices, because of their significant computational overhead. To address these concerns, we propose a data protection scheme to store the encrypted IoT data in a cloud, while still allowing query processing over the encrypted data. Our proposed scheme features a novel encrypted data sharing scheme based on Boneh-Goh-Nissim (BGN) cryptosystem, with revocation capabilities and <italic xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">in-situ</i> key updates. We perform exhaustive experiments on real datasets, to assess the feasibility of the proposed scheme on the resource constrained IoT devices. The results show the feasibility of our scheme, together with the ability to provide a high level of security. The results also show that our scheme significantly reduces the computation, storage and energy overheads than the best performed scheme in the state-of-the-art.

Securing Seaport Logistic Vehicles Using a Distributed Ledger-Based Credential Management System

Major maritime carriers are globally demanding improvements in the efficiency of port operations. Cargo carried by ships must be loaded and unloaded quickly with minimal stopover time in the port. This requirement mandates seaports to deploy cutting-edge technology to the port area so that logistic processes are increasingly efficient and reliable. In this scenario, the attack surface of such critical infrastructure is growing very rapidly and advanced security techniques must be deployed to enforce a high attack resilience. A Distributed Ledger-based Credential Management System exploiting a Distributed Ledger Technology (DLT) to enable transparent and real-time tracking of logistic vehicles and cargos within a terminal is presented in this paper. Based on a customization of Vehicular Ad-Hoc Network (VANET) security standards, the proposed scheme provides authentication, authorization, and revocation capabilities to promptly exclude misbehaving logistic vehicles from the system, while maintaining an immutable record of all the logistic vehicles' activity. The laboratory validation demonstrates that the delay of the devised scheme is not dependent on the quay area capacity, thus being applicable in seaports of any size. Furthermore, the effectiveness of the solution is demonstrated with the field trial results obtained with the EU Horizon 2020 COREALIS project testbed deployed in the Port of Livorno.

An Efficient Access Control Scheme With Outsourcing and Attribute Revocation for Fog-Enabled E-Health

Fog computing is increasingly popular partly due to its capability to minimize data transfer and latency requirements, for example by moving some of the computational operations away from the cloud servers and closer to the users. To achieve fine-grained access control in fog-enabled application scenarios to guarantee data security and user privacy, one could use ciphertext-policy attribute-based encryption (CP-ABE). However, the lack of an effective mechanism to carry out access right revocation in conventional CP-ABE schemes limits the deployment of such schemes in practice. Thus, we propose an efficient CP-ABE scheme with attribute revocation capability, designed to construct a fine-grained access control system in fog-enabled E-health (referred to as AC-FEH). In our AC-FEH system, fog nodes undertake data encryption and decryption operations; thus, computational costs for data owners and users are minimized. In comparison to several other competing access control schemes based on CP-ABE, our AC-FEH system reduces the computational costs associated with encryption and decryption. We also prove the selective security of the underlying CP-ABE scheme under the intractability assumption of the $q$ -parallel BDHE problem.

Lightweight attribute based encryption scheme for mobile cloud assisted cyber-physical systems

Protecting data in Cyber-Physical Systems (CPS) has been a longstanding challenge. The tradition Attribute Based Encryption (ABE) is known for its high computation load which creates a significant challenge for resource constrained mobile devices. In this paper, we propose a Lightweight Attribute Based Encryption Scheme (LABE) for mobile cloud-assisted CPS based on a proxy service architecture and a new ciphertext policy ABE. In particular, mobile devices will solely perform symmetric encryption by joining authentication and encryption proxy services encapsulated in RESTful. Encryption shall not need pairing and then ciphertext can be decrypted with one pairing. Security analysis shows that the proposed LABE is secure with fine grained access control and users revocation capability. The computation complexity shows that the proposed scheme imposes low overhead on mobile devices and performs very well in mobile cloud-assisted CPS.

User Revocation Mechanism for Service Oriented Wireless Adhoc Networks

Adhoc network is basically infrastructure less in nature and it is vulnerable to attacks. In such a network it is necessary to create the security autonomously without the involvement of centralized architecture. Address allocation, name resolution, services rendering, authentication and access control policies represent some of the functionalities that are supported by the Adhoc Networks. To solve the above issue, a novel security protocol is proposed for the Passionate network formation. Initial network formation done based on trust. For each newly added user authorization is performed using certificate generation. Authentication is carried out using certificate verification mechanism. Session key is used by all the nodes in the network, for the defended communication. Symmetric key encryption is used for data encryption. Asymmetric cryptography is used for session key encryption and signature generation. Session key updating is carried out based on expiration time. To revoke the attacker from participating in the network, User revocation mechanism is contributed to the proposed security protocol. Security is enhanced with revocation capabilities.

A New Revocation Method for Standard Model Group Signature

Membership revocation is practically necessary for group signature schemes. At present, most revocable group signature schemes are based on ROM model and many standard model group signature schemes do not support revocation. We present a novel and general revocation method for standard model group signature scheme based on length-reducing commitment and Groth-Sahai proof system, and demonstrate its usage by adding revocation capability to the Groth’s full secure group signature scheme. The new method supports two different kinds of linkability for members when signing.

Long-lived Self-healing Group Key Distribution Scheme in Wireless Sensor Networks

The self-healing group key distribution with revocation can deal with the session key distribution problem for secure group communication over an unreliable wireless network, with the capability of resistance to the packet loss and the collusion attack. However, since previous self-healing group key distribution schemes are restricted to m sessions, they will be reset frequently, which leads to large power and bandwidth consumption. In order to prolong the life span of the self-healing group key distribution schemes and save energy, we propose an efficient long-lived δ -self-healing group key distribution scheme with revocation and collusion resistance capabilities for wireless sensor networks in this paper. Our proposed scheme is capable of supporting infinite sessions by updating the personal secret of group members during each session and performing a partial revocation. Compared to previous schemes under same conditions, security and performance analysis results show that our proposed scheme not only resolves the lifetime extension problem, but also achieves better security performance with lower storage and communication costs.

Enhanced Privacy ID: A Direct Anonymous Attestation Scheme with Enhanced Revocation Capabilities

Direct Anonymous Attestation (DAA) is a scheme that enables the remote authentication of a Trusted Platform Module (TPM) while preserving the user's privacy. A TPM can prove to a remote party that it is a valid TPM without revealing its identity and without linkability. In the DAA scheme, a TPM can be revoked only if the DAA private key in the hardware has been extracted and published widely so that verifiers obtain the corrupted private key. If the unlinkability requirement is relaxed, a TPM suspected of being compromised can be revoked even if the private key is not known. However, with the full unlinkability requirement intact, if a TPM has been compromised but its private key has not been distributed to verifiers, the TPM cannot be revoked. Furthermore, a TPM cannot be revoked from the issuer, if the TPM is found to be compromised after the DAA issuing has occurred. In this paper, we present a new DAA scheme called Enhanced Privacy ID (EPID) scheme that addresses the above limitations. While still providing unlinkability, our scheme provides a method to revoke a TPM even if the TPM private key is unknown. This expanded revocation property makes the scheme useful for other applications such as for driver's license. Our EPID scheme is efficient and provably secure in the same security model as DAA, i.e., in the random oracle model under the strong RSA assumption and the decisional Diffie-Hellman assumption.

속성기반 암호화를 이용한 원격 헬스케어 모니터링 시스템

원격 헬스케어(e-Healthcare) 서비스에서 취급되는 의료정보는 개인의 프라이버시를 침해할 수 있으므로 암호화 등의 보안기술 도입이 필수적이다. 민감한 의료정보를 보호하기 위해서 접근 권한을 위임받은 사용자만 데이터에 접근 가능하며 또한, 위임된 접근 권한을 철회하는 기능이 필요하다. 이러한 요구사항에 근거하여 속성기반 암호화가 제안되었다. 본 논문에서는 안전한 원격 헬스케어 서비스를 위해서 의료데이터의 접근 권한에 대한 위임 및 철회기능을 수행할 수 있는 속성기반 암호화를 원격 헬스케어 모니터링 시스템에 적용한다. 그리고 속성기반 암호화를 이용하여 원격 헬스케어 모니터링 시스템을 구성한다. 마지막으로 시스템 이용에 장애가 될 수 있는 사용자간의 공모 공격에 대해서 분석한다. To ensure privacy of individual information in remote healthcare service, health data should be protected through a secure technology such as encryption scheme. Only user who delegated decryption right can access to sensitive health data and delegator needs capability for revocating access privilege. Recently, in ubiquitous environment, CP-ABTD(Ciphertext-Policy Attribute-Based Threshold Decryption with Flexible Delegation and Revocation of User Attributes) which extends CP-ABE(Ciphertext-Policy Attribute-Based Encryption) has been proposed for these requirements. In this paper, we construct remote healthcare monitoring system with delegation and revocation capability for attribute in CP-ABTD. Finally, we analyze collusion attack between users in our system.

A more efficient and secure ID-based remote mutual authentication with key agreement scheme for mobile devices on elliptic curve cryptosystem

Recently, Yang and Chang proposed an identity-based remote login scheme using elliptic curve cryptography for the users of mobile devices. We have analyzed the security aspects of the Yang and Chang's scheme and identified some security flaws. Also two improvements of the Yang and Chang's scheme have been proposed recently, however, it has been found that the schemes have similar security flaws as in the Yang and Chang's scheme. In order to remove the security pitfalls of the Yang and Chang and the subsequent schemes, we proposed an enhanced remote user mutual authentication scheme that uses elliptic curve cryptography and identity-based cryptosystem with three-way challenge-response handshake technique. It supports flawless mutual authentication of participants, agreement of session key and the leaked key revocation capability. In addition, the proposed scheme possesses low power consumption, low computation cost and better security attributes. As a result, the proposed scheme seems to be more practical and suitable for mobile users for secure Internet banking, online shopping, online voting, etc.

Attribute-Based Access Control with Efficient Revocation in Data Outsourcing Systems

Some of the most challenging issues in data outsourcing scenario are the enforcement of authorization policies and the support of policy updates. Ciphertext-policy attribute-based encryption is a promising cryptographic solution to these issues for enforcing access control policies defined by a data owner on outsourced data. However, the problem of applying the attribute-based encryption in an outsourced architecture introduces several challenges with regard to the attribute and user revocation. In this paper, we propose an access control mechanism using ciphertext-policy attribute-based encryption to enforce access control policies with efficient attribute and user revocation capability. The fine-grained access control can be achieved by dual encryption mechanism which takes advantage of the attribute-based encryption and selective group key distribution in each attribute group. We demonstrate how to apply the proposed mechanism to securely manage the outsourced data. The analysis results indicate that the proposed scheme is efficient and secure in the data outsourcing systems.

Enhanced privacy ID from bilinear pairing for hardware authentication and attestation

Enhanced privacy ID (EPID) is a cryptographic scheme that enables the remote authentication and attestation of a hardware device while preserving the privacy of the device. EPID can be seen as a direct anonymous attestation scheme with enhanced revocation capabilities. In EPID, a device can be revoked if the private key embedded in the hardware device has been extracted and published widely so that the revocation manager finds the corrupted private key. In addition, the revocation manager can revoke a device based on the signatures the device has created, if the private key of the device is not known. In this paper1, we introduce a new security notion of EPID including the formal definitions of anonymity and unforgeability. We also give a construction of an EPID scheme from bilinear pairing. Our EPID scheme is efficient and provably secure in the random oracle model under the strong Diffie-Hellman assumption and the decisional Diffie-Hellman assumption.

Self-healing key distribution scheme with long service time

Self-healing key distribution schemes for broadcast encryption are capable of recovering missed group keys and resisting a collusion attack of up to t revoked users. However, since previous schemes have been considered only m sessions, it does not suitable to support infinite sessions. In the paper, we propose an efficient δ-self healing key distribution scheme with revocation capability. The proposed scheme can support infinite sessions by updating the private key of users and supporting a partial revocation. The communication overhead of the proposed scheme is compared with several previous works.

Anti-collusive Self-healing Key Distribution Scheme with Revocation Capability

Anti-collusive Self-healing Key Distribution Scheme with Revocation Capability

A loss-tolerant group key management scheme with revocation capability for wireless sensor network

A new group key management scheme against the unreliable wireless communication channel and unsafe environment was proposed for wireless sensor network (WSN). In the proposed scheme, broadcast polynomial, generated over finite field Fq based on the secret sharing, was employed to revoke compromised sensor nodes. In order to tolerate key-update message loss, group session keys were generated as one-way hash chain sequence and distributed in advance. The analysis showes that the scheme has better performance in terms of the computation and communication overhead.

Group signatures with reduced bandwidth

Group signatures are generalised credential/member authentication schemes with wide applications. Membership revocation problem is a major issue of group signatures, and is often resolved through an additional protocol which would encumber the whole group signature both in computation and storage, as Camenisch et al. did to ACJT&apos;s group signature scheme (the first ever practical group signature based on RSA problem put forward by Ateniese et al. at Crypto&apos;00) by dynamic accumulator. Boneh et al. applied Camenisch et al.&apos;s dynamic accumulator based revocation reversely, resulted in short group signature. We formally define the method used by Boneh et al., named reversed dynamic accumulator in this paper, and apply it on some previous group signatures to obtain improved ones with revocation capability, reduced bandwidth (signature size) and less signature generation computations. We also address the problems unsolved in Boneh et al.&apos;s work, e.g. how to open a group signature since the current certificate may no longer be the one stored when it is firstly generated.

자가 치료 기능과 취소 능력을 가진 효율적인 그룹키 분배 기법

자가 치료 기능을 가진 그룹키 분배 기법은 신뢰성이 약한 네트워크 환경에서 특정 세션의 그룹키 정보를 수신하지 못한 사용자가 그룹 매니저와의 추가적인 통신 없이 스스로 세션키를 복구할 수 있도록 해주는 방식이다. 본 논문에서는 자가 치료 기능을 가진 새로운 그룹키 분배 기법을 제안한다. 여기에서 제안하는 방식은 취소 능력을 가지며, 사용자의 저장 메모리 관점에서 최적이고, 통신 복잡도 측면에서는 기존의 방법들 보다 효율적이다. 최근에 제안된 Blondo 등(13)과 Liu 등(14)의 방식에서 사용한 브로드캐스트 방법을 적절히 원용함으로써 메모리 정장소는 최적이고, 통신 복잡도 관점에서는 기존 두 방식들보다 약 2배정도 개선된 결과를 얻는다. 또한, 제안한 프로토콜이 t-차 순방향 및 역방향 기밀성을 만족한다는 사실을 증명하고, 단일 브로드캐스트 메시지를 통해서 그룹세션키를 복구할 수 있는 보다 효율적인 자가 치료 기능을 가진 그룹키 분배 기법도 가능함을 보인다. In the self-healing group key distribution scheme, users are capable of recovering lost group keys on their own without requesting additional transmission from the group manager, where there is no reliable network infrastructure. In this paper, we propose a new self-healing group key distribution scheme with revocation capability, which is optimal in terms of user memory storage and more efficient in terms of communication complexity than the previous results. We obtain a slightly improved result from (13) and (14) by using the new broadcasting method. In addition, we prove that our scheme has the properties of t-wise forward secrecy and t-wise backward secrecy, and extend this self-healing approach to the session key recovery scheme from a single broadcast message.

A Public-Key Traitor Tracing Scheme with Revocation Using Dynamic Shares

We proposed a new public-key traitor tracing scheme with revocation capability using dynamic shares and entity revocation techniques. Our scheme’s traitor tracing and revocation programs cohere tightly. The size of the enabling block of our scheme is independent of the number of receivers. Each receiver holds one decryption key only. The distinct feature of our scheme is that when traitors are found, we can revoke their private keys (up to some threshold z) without updating the private keys of other receivers. In particular, no revocation messages are broadcast and all receivers do nothing. Previously proposed revocation schemes need update existing keys and entail large amount of broadcast messages. Our traitor tracing algorithm works in a black-box way. It is conceptually simple and fully k-resilient, that is, it can find all traitors if the number of them is k or less. The encryption algorithm of our scheme is semantically secure assuming that the decisional Diffie-Hellman problem is hard.