Visible to the public Biblio

Found 452 results

Filters: Keyword is Encryption  [Clear All Filters]
2020-02-18
Das, Debayan, Nath, Mayukh, Chatterjee, Baibhab, Ghosh, Santosh, Sen, Shreyas.  2019.  S℡LAR: A Generic EM Side-Channel Attack Protection through Ground-Up Root-Cause Analysis. 2019 IEEE International Symposium on Hardware Oriented Security and Trust (HOST). :11–20.
The threat of side-channels is becoming increasingly prominent for resource-constrained internet-connected devices. While numerous power side-channel countermeasures have been proposed, a promising approach to protect the non-invasive electromagnetic side-channel attacks has been relatively scarce. Today's availability of high-resolution electromagnetic (EM) probes mandates the need for a low-overhead solution to protect EM side-channel analysis (SCA) attacks. This work, for the first time, performs a white-box analysis to root-cause the origin of the EM leakage from an integrated circuit. System-level EM simulations with Intel 32 nm CMOS technology interconnect stack, as an example, reveals that the EM leakage from metals above layer 8 can be detected by an external non-invasive attacker with the commercially available state-of-the-art EM probes. Equipped with this `white-box' understanding, this work proposes S℡LAR: Signature aTtenuation Embedded CRYPTO with Low-Level metAl Routing, which is a two-stage solution to eliminate the critical signal radiation from the higher-level metal layers. Firstly, we propose routing the entire cryptographic core within the local lower-level metal layers, whose leakage cannot be picked up by an external attacker. Then, the entire crypto IP is embedded within a Signature Attenuation Hardware (SAH) which in turn suppresses the critical encryption signature before it routes the current signature to the highly radiating top-level metal layers. System-level implementation of the S℡LAR hardware with local lower-level metal routing in TSMC 65 nm CMOS technology, with an AES-128 encryption engine (as an example cryptographic block) operating at 40 MHz, shows that the system remains secure against EM SCA attack even after 1M encryptions, with 67% energy efficiency and 1.23× area overhead compared to the unprotected AES.
Saha, Arunima, Srinivasan, Chungath.  2019.  White-Box Cryptography Based Data Encryption-Decryption Scheme for IoT Environment. 2019 5th International Conference on Advanced Computing Communication Systems (ICACCS). :637–641.
The economic progress of the Internet of Things (IoT) is phenomenal. Applications range from checking the alignment of some components during a manufacturing process, monitoring of transportation and pedestrian levels to enhance driving and walking path, remotely observing terminally ill patients by means of medical devices such as implanted devices and infusion pumps, and so on. To provide security, encrypting the data becomes an indispensable requirement, and symmetric encryptions algorithms are becoming a crucial implementation in the resource constrained environments. Typical symmetric encryption algorithms like Advanced Encryption Standard (AES) showcases an assumption that end points of communications are secured and that the encryption key being securely stored. However, devices might be physically unprotected, and attackers may have access to the memory while the data is still encrypted. It is essential to reserve the key in such a way that an attacker finds it hard to extract it. At present, techniques like White-Box cryptography has been utilized in these circumstances. But it has been reported that applying White-Box cryptography in IoT devices have resulted in other security issues like the adversary having access to the intermediate values, and the practical implementations leading to Code lifting attacks and differential attacks. In this paper, a solution is presented to overcome these problems by demonstrating the need of White-Box Cryptography to enhance the security by utilizing the cipher block chaining (CBC) mode.
2020-02-17
Meijer, Carlo, van Gastel, Bernard.  2019.  Self-Encrypting Deception: Weaknesses in the Encryption of Solid State Drives. 2019 IEEE Symposium on Security and Privacy (SP). :72–87.
We have analyzed the hardware full-disk encryption of several solid state drives (SSDs) by reverse engineering their firmware. These drives were produced by three manufacturers between 2014 and 2018, and are both internal models using the SATA and NVMe interfaces (in a M.2 or 2.5" traditional form factor) and external models using the USB interface. In theory, the security guarantees offered by hardware encryption are similar to or better than software implementations. In reality, we found that many models using hardware encryption have critical security weaknesses due to specification, design, and implementation issues. For many models, these security weaknesses allow for complete recovery of the data without knowledge of any secret (such as the password). BitLocker, the encryption software built into Microsoft Windows will rely exclusively on hardware full-disk encryption if the SSD advertises support for it. Thus, for these drives, data protected by BitLocker is also compromised. We conclude that, given the state of affairs affecting roughly 60% of the market, currently one should not rely solely on hardware encryption offered by SSDs and users should take additional measures to protect their data.
Jolfaei, Alireza, Kant, Krishna.  2019.  Privacy and Security of Connected Vehicles in Intelligent Transportation System. 2019 49th Annual IEEE/IFIP International Conference on Dependable Systems and Networks – Supplemental Volume (DSN-S). :9–10.
The paper considers data security and privacy issues in intelligent transportation systems which involve data streams coming out from individual vehicles to road side units. In this environment, there are issues in regards to the scalability of key management and computation limitations at the edge of the network. To address these issues, we suggest the formation of groups in the vehicular layer, where a group leader is assigned to communicate with group members and the road side unit. We propose a lightweight permutation mechanism for preserving the confidentiality and privacy of sensory data.
Alfaleh, Faleh, Alfehaid, Haitham, Alanzy, Mohammed, Elkhediri, Salim.  2019.  Wireless Sensor Networks Security: Case study. 2019 2nd International Conference on Computer Applications Information Security (ICCAIS). :1–4.
Wireless Sensor Networks (WSNs) are important and becoming more important as we integrate wireless sensor networks and the internet with different things, which has changed our life, and it is affected everywhere in our life like shopping, storage, live monitoring, smart home etc., called Internet of Things (IoT), as any use of the network physical devices that included in electronics, software, sensors, actuators, and connectivity which makes available these things to connect, collect and exchange data, and the most importantly thing is the accuracy of the data that has been collected in the Internet of Things, detecting sensor data with faulty readings is an important issue of secure communication and power consumption. So, requirement of energy-efficiency and integrity of information is mandatory.
2020-02-10
Byun, Jin Wook.  2019.  An efficient multi-factor authenticated key exchange with physically unclonable function. 2019 International Conference on Electronics, Information, and Communication (ICEIC). :1–4.
In this paper, we propose an efficient and secure physically unclonable function based multi-factor authenticated key exchange (PUF-MAKE). In a PUF-MAKE setting, we suppose two participants; a user and a server. The user keeps multi-factor authenticators and securely holds a PUF-embedded device while the server maintains PUF outputs for authentication. We first study on how to efficiently construct a PUF-MAKE protocol. The main difficulty comes from that it should establish a common key from both multi-factor authenticators and a PUF-embedded device. Our construction is the first secure PUF-MAKE protocol that just needs three communication flows.
Ruchkin, Vladimir, Fulin, Vladimir, Pikulin, Dmitry, Taganov, Aleksandr, Kolesenkov, Aleksandr, Ruchkina, Ekaterina.  2019.  Heterogenic Multi-Core System on Chip for Virtual Based Security. 2019 8th Mediterranean Conference on Embedded Computing (MECO). :1–5.
The paper describes the process of coding information in the heterogenic multi-core system on chip for virtual-based security designed For image processing, signal processing and neural networks emulation. The coding of information carried out in assembly language according to the GOST. This is an implementation of the GOST - a standard symmetric key block cipher has a 64-bit block size and 256-bit key size.
Ramu, Gandu, Mishra, Zeesha, Acharya, B..  2019.  Hardware implementation of Piccolo Encryption Algorithm for constrained RFID application. 2019 9th Annual Information Technology, Electromechanical Engineering and Microelectronics Conference (IEMECON). :85–89.
The deployment of smart devices in IoT applications are increasing with tremendous pace causing severe security concerns, as it trade most of private information. To counter that security issues in low resource applications, lightweight cryptographic algorithms have been introduced in recent past. In this paper we propose efficient hardware architecture of piccolo lightweight algorithm uses 64 bits block size with variable key size of length 80 and 128 bits. This paper introduces novel hardware architecture of piccolo-80, to supports high speed RFID security applications. Different design strategies are there to optimize the hardware metrics trade-off for particular application. The algorithm is implemented on different family of FPGAs with different devices to analyze the performance of design in 4 input LUTs and 6 input LUTs implementations. In addition, the results of hardware design are evaluated and compared with the most relevant lightweight block ciphers, shows the proposed architecture finds its utilization in terms of speed and area optimization from the hardware resources. The increment in throughput with optimized area of this architecture suggests that piccolo can applicable to implement for ultra-lightweight applications also.
Korzhik, Valery, Duy Cuong, Nguyen, Morales-Luna, Guillermo.  2019.  Cipher Modification Against Steganalysis Based on NIST Tests. 2019 24th Conference of Open Innovations Association (FRUCT). :179–186.

Part of our team proposed a new steganalytic method based on NIST tests at MMM-ACNS 2017 [1], and it was encouraged to investigate some cipher modifications to prevent such types of steganalysis. In the current paper, we propose one cipher modification based on decompression by arithmetic source compression coding. The experiment shows that the current proposed method allows to protect stegosystems against steganalysis based on NIST tests, while security of the encrypted embedded messages is kept. Protection of contemporary image steganography based on edge detection and modified LSB against NIST tests steganalysis is also presented.

2020-01-27
Takahashi, Ririka, Tanizawa, Yoshimichi, Dixon, Alexander.  2019.  A High-Speed Key Management Method for Quantum Key Distribution Network. 2019 Eleventh International Conference on Ubiquitous and Future Networks (ICUFN). :437–442.

Quantum Key Distribution (QKD) is a technique for sharing encryption keys between two adjacent nodes. It provides unconditional secure communication based on the laws of physics. From the viewpoint of network research, QKD is considered to be a component for providing secure communication in network systems. A QKD network enables each node to exchange encryption keys with arbitrary nodes. However previous research did not focus on the processing speed of the key management method essential for a QKD network. This paper focuses on the key management method assuming a high-speed QKD system for which we clarify the design, propose a high-speed method, and evaluate the throughput. The proposed method consists of four modules: (1) local key manager handling the keys generated by QKD, (2) one-time pad tunnel manager establishing the transparent encryption link, (3) global key manager generating the keys for application communication, and (4) web API providing keys to the application. The proposed method was implemented in software and evaluated by emulating QKD key generation and application key consumption. The evaluation result reveals that it is capable of handling the encryption keys at a speed of 414 Mb/s, 185 Mb/s, 85 Mb/s and 971 Mb/s, for local key manager, one-time pad tunnel manager, global key manager and web API, respectively. These are sufficient for integration with a high-speed QKD system. Furthermore, the method allows the high-speed QKD system consisting of two nodes to expand corresponding to the size of the QKD network without losing the speed advantage.

2020-01-21
Ferretti, Luca, Marchetti, Mirco, Colajanni, Michele.  2019.  Fog-Based Secure Communications for Low-Power IoT Devices. ACM Transactions on Internet Technology (TOIT). 19:27:1-27:21.
Designing secure, scalable, and resilient IoT networks is a challenging task because of resource-constrained devices and no guarantees of reliable network connectivity. Fog computing improves the resiliency of IoT, but its security model assumes that fog nodes are fully trusted. We relax this latter constraint by proposing a solution that guarantees confidentiality of messages exchanged through semi-honest fog nodes thanks to a lightweight proxy re-encryption scheme. We demonstrate the feasibility of the solution by applying it to IoT networks of low-power devices through experiments on microcontrollers and ARM-based architectures.
Vo, Tri Hoang, Fuhrmann, Woldemar, Fischer-Hellmann, Klaus-Peter, Furnell, Steven.  2019.  Efficient Privacy-Preserving User Identity with Purpose-Based Encryption. 2019 International Symposium on Networks, Computers and Communications (ISNCC). :1–8.
In recent years, users may store their Personal Identifiable Information (PII) in the Cloud environment so that Cloud services may access and use it on demand. When users do not store personal data in their local machines, but in the Cloud, they may be interested in questions such as where their data are, who access it except themselves. Even if Cloud services specify privacy policies, we cannot guarantee that they will follow their policies and will not transfer user data to another party. In the past 10 years, many efforts have been taken in protecting PII. They target certain issues but still have limitations. For instance, users require interacting with the services over the frontend, they do not protect identity propagation between intermediaries and against an untrusted host, or they require Cloud services to accept a new protocol. In this paper, we propose a broader approach that covers all the above issues. We prove that our solution is efficient: the implementation can be easily adapted to existing Identity Management systems and the performance is fast. Most importantly, our approach is compliant with the General Data Protection Regulation from the European Union.
Zhou, Yiwen, Shen, Qili, Dong, Mianxiong, Ota, Kaoru, Wu, Jun.  2019.  Chaos-Based Delay-Constrained Green Security Communications for Fog-Enabled Information-Centric Multimedia Network. 2019 IEEE 89th Vehicular Technology Conference (VTC2019-Spring). :1–6.
The Information-Centric Network possessing the content-centric features, is the innovative architecture of the next generation of network. Collaborating with fog computing characterized by its strong edge power, ICN will become the development trend of the future network. The emergence of Information-Centric Multimedia Network (ICMN) can meet the increasing demand for transmission of multimedia streams in the current Internet environment. The data transmission has become more delay-constrained and convenient because of the distributed storage, the separation between the location of information and terminals, and the strong cacheability of each node in ICN. However, at the same time, the security of the multimedia streams in the delivery process still requires further protection against wiretapping, interception or attacking. In this paper, we propose the delay-constrained green security communications for ICMN based on chaotic encryption and fog computing so as to transmit multimedia streams in a more secure and time-saving way. We adapt a chaotic cryptographic method to ICMN, implementing the encryption and decryption of multimedia streams. Meanwhile, the network edge capability to process the encryption and decryption is enhanced. Thanks to the fog computing, the strengthened transmission speed of the multimedia streams can fulfill the need for short latency. The work in the paper is of great significance to improve the green security communications of multimedia streams in ICMN.
Suksomboon, Kalika, Shen, Zhishu, Ueda, Kazuaki, Tagami, Atsushi.  2019.  C2P2: Content-Centric Privacy Platform for Privacy-Preserving Monitoring Services. 2019 IEEE 43rd Annual Computer Software and Applications Conference (COMPSAC). 1:252–261.
Motivated by ubiquitous surveillance cameras in a smart city, a monitoring service can be provided to citizens. However, the rise of privacy concerns may disrupt this advanced service. Yet, the existing cloud-based services have not clearly proven that they can preserve Wth-privacy in which the relationship of three types of information, i.e., who requests the service, what the target is and where the camera is, does not leak. We address this problem by proposing a content-centric privacy platform (C2P2) that enables the construction of a Wth-privacy-preserving monitoring service without cloud dependency. C2P2 uses an image classification model of a target serving as the key to access the monitoring service specific to the target. In C2P2, communication is based on information-centric networking (ICN) that enables privacy preservation to be centered on the content itself rather than relying on a centralized system. Moreover, to preserve the privacy of bystanders, C2P2 separates the sensitive information (e.g., human faces) from the non-sensitive information (e.g., image background), while the privacy-aware forwarding strategies in C2P2 enable data aggregation and prevent privacy leakage resulting from false positive of image recognition. We evaluate the privacy leakage of C2P2 compared to that of the cloud-based system. The privacy analysis shows that, compared to the cloud-based system, C2P2 achieves a lower privacy loss ratio while reducing the communication cost significantly.
2020-01-20
Thiemann, Benjamin, Feiten, Linus, Raiola, Pascal, Becker, Bernd, Sauer, Matthias.  2019.  On Integrating Lightweight Encryption in Reconfigurable Scan Networks. 2019 IEEE European Test Symposium (ETS). :1–6.

Reconfigurable Scan Networks (RSNs) are a powerful tool for testing and maintenance of embedded systems, since they allow for flexible access to on-chip instrumentation such as built-in self-test and debug modules. RSNs, however, can be also exploited by malicious users as a side-channel in order to gain information about sensitive data or intellectual property and to recover secret keys. Hence, implementing appropriate counter-measures to secure the access to and data integrity of embedded instrumentation is of high importance. In this paper we present a novel hardware and software combined approach to ensure data privacy in IEEE Std 1687 (IJTAG) RSNs. To do so, both a secure IJTAG compliant plug-and-play instrument wrapper and a versatile software toolchain are introduced. The wrapper demonstrates the necessary architectural adaptations required when using a lightweight stream cipher, whereas the software toolchain provides a seamless integration of the testing workflow with stream cipher. The applicability of the method is demonstrated by an FPGA-based implementation. We report on the performance of the developed instrument wrapper, which is empirically shown to have only a small impact on the workflow in terms of hardware overhead, operational costs and test time overhead.

Noura, Hassan, Couturier, Raphael, Pham, Congduc, Chehab, Ali.  2019.  Lightweight Stream Cipher Scheme for Resource-Constrained IoT Devices. 2019 International Conference on Wireless and Mobile Computing, Networking and Communications (WiMob). :1–8.

The Internet of Things (IoT) systems are vulnerable to many security threats that may have drastic impacts. Existing cryptographic solutions do not cater for the limitations of resource-constrained IoT devices, nor for real-time requirements of some IoT applications. Therefore, it is essential to design new efficient cipher schemes with low overhead in terms of delay and resource requirements. In this paper, we propose a lightweight stream cipher scheme, which is based, on one hand, on the dynamic key-dependent approach to achieve a high security level, and on the other hand, the scheme involves few simple operations to minimize the overhead. In our approach, cryptographic primitives change in a dynamic lightweight manner for each input block. Security and performance study as well as experimentation are performed to validate that the proposed cipher achieves a high level of efficiency and robustness, making it suitable for resource-constrained IoT devices.

Chawla, Nikhil, Singh, Arvind, Rahman, Nael Mizanur, Kar, Monodeep, Mukhopadhyay, Saibal.  2019.  Extracting Side-Channel Leakage from Round Unrolled Implementations of Lightweight Ciphers. 2019 IEEE International Symposium on Hardware Oriented Security and Trust (HOST). :31–40.

Energy efficiency and security is a critical requirement for computing at edge nodes. Unrolled architectures for lightweight cryptographic algorithms have been shown to be energy-efficient, providing higher performance while meeting resource constraints. Hardware implementations of unrolled datapaths have also been shown to be resistant to side channel analysis (SCA) attacks due to a reduction in signal-to-noise ratio (SNR) and an increased complexity in the leakage model. This paper demonstrates optimal leakage models and an improved CFA attack which makes it feasible to extract first-order side-channel leakages from combinational logic in the initial rounds of unrolled datapaths. Several leakage models, targeting initial rounds, are explored and 1-bit hamming weight (HW) based leakage model is shown to be an optimal choice. Additionally, multi-band narrow bandpass filtering techniques in conjunction with correlation frequency analysis (CFA) is demonstrated to improve SNR by up to 4×, attributed to the removal of the misalignment effect in combinational logics and signal isolation. The improved CFA attack is performed on side channel signatures acquired for 7-round unrolled SIMON datapaths, implemented on Sakura-G (XILINX spartan 6, 45nm) based FPGA platform and a 24× reduction in minimum-traces-to-disclose (MTD) for revealing 80% of the key bits is demonstrated with respect to conventional time domain correlation power analysis (CPA). Finally, the proposed method is successfully applied to a fully-unrolled datapath for PRINCE and a parallel round-based datapath for Advanced Encryption Standard (AES) algorithm to demonstrate its general applicability.

Khairullin, Ilias, Bobrov, Vladimir.  2019.  On Cryptographic Properties of Some Lightweight Algorithms and its Application to the Construction of S-Boxes. 2019 IEEE Conference of Russian Young Researchers in Electrical and Electronic Engineering (EIConRus). :1807–1810.

We consider some approaches to the construction of lightweight block ciphers and introduce the definitions for "index of strong nonlinearity" and "index of perfection". For PRESENT, MIDORI, SKINNY, CLEFIA, LILLIPUT mixing and nonlinear properties were evaluated. We obtain the exact values of the exponents for mixing matrices of round functions and the upper bounds for indexes of perfection and strong nonlinearity. It was determined by the experiment that each coordinate function of output block is nonlinear during 500 rounds. We propose the algorithmic realization of 16×16 S-box based on the modified additive generator with lightweight cipher SPECK as a modification which does not demand memory for storage huge substitution tables. The best value of the differential characteristic of such S-box is 18/216, the minimal nonlinearity degree of coordinate functions is equal to 15 and the minimal linear characteristic is 788/215.

Elaguech, Amira, Kchaou, Afef, El Hadj Youssef, Wajih, Ben Othman, Kamel, Machhout, Mohsen.  2019.  Performance evaluation of lightweight Block Ciphers in soft-core processor. 2019 19th International Conference on Sciences and Techniques of Automatic Control and Computer Engineering (STA). :101–105.

The Internet of Things (IoT) and RFID devices are essential parts of the new information technology generation. They are mostly characterized by their limited power and computing resources. In order to ensure their security under computing and power constraints, a number of lightweight cryptography algorithms has emerged. This paper outlines the performance analysis of six lightweight blocks crypto ciphers with different structures - LED, PRESENT, HIGHT, LBlock, PICCOLO and TWINE on a LEON3 open source processor. We have implemented these crypto ciphers on the FPGA board using the C language and the LEON3 processor. Analysis of these crypto ciphers is evaluated after considering various benchmark parameters like throughput, execution time, CPU performance, AHB bandwidth, Simulator performance, and speed. These metrics are tested with different key sizes provided by each crypto algorithm.

Sehrawat, Deepti, Gill, Nasib Singh, Devi, Munisha.  2019.  Comparative Analysis of Lightweight Block Ciphers in IoT-Enabled Smart Environment. 2019 6th International Conference on Signal Processing and Integrated Networks (SPIN). :915–920.

With the rapid technological growth in the present context, Internet of Things (IoT) has attracted the worldwide attention and has become pivotal technology in the smart computing environment of 21st century. IoT provides a virtual view of real-life things in resource-constrained environment where security and privacy are of prime concern. Lightweight cryptography provides security solutions in resource-constrained environment of IoT. Several software and hardware implementation of lightweight ciphers have been presented by different researchers in this area. This paper presents a comparative analysis of several lightweight cryptographic solutions along with their pros and cons, and their future scope. The comparative analysis may further help in proposing a 32-bit ultra-lightweight block cipher security model for IoT enabled applications in the smart environment.

Laaboudi, Younes, Olivereau, Alexis, Oualha, Nouha.  2019.  An Intrusion Detection and Response Scheme for CP-ABE-Encrypted IoT Networks. 2019 10th IFIP International Conference on New Technologies, Mobility and Security (NTMS). :1–5.

This paper introduces a new method of applying both an Intrusion Detection System (IDS) and an Intrusion Response System (IRS) to communications protected using Ciphertext-Policy Attribute-based Encryption (CP-ABE) in the context of the Internet of Things. This method leverages features specific to CP-ABE in order to improve the detection capabilities of the IDS and the response ability of the network. It also enables improved privacy towards the users through group encryption rather than one-to-one shared key encryption as the policies used in the CP-ABE can easily include the IDS as an authorized reader. More importantly, it enables different levels of detection and response to intrusions, which can be crucial when using anomaly-based detection engines.

Wang, Qihua, Lv, Gaoyan, Sun, Xiuling.  2019.  Distributed Access Control with Outsourced Computation in Fog Computing. 2019 Chinese Control And Decision Conference (CCDC). :2446–2450.

With the rapid development of Internet of things (IOT) and big data, the number of network terminal devices and big data transmission are increasing rapidly. Traditional cloud computing faces a great challenge in dealing with this massive amount of data. Fog computing which extends the computing at the edge of the network can provide computation and data storage. Attribute based-encryption can effectively achieve the fine-grained access control. However, the computational complexity of the encryption and decryption is growing linearly with the increase of the number of attributes. In order to reduce the computational cost and guarantee the confidentiality of data, distributed access control with outsourced computation in fog computing is proposed in this paper. In our proposed scheme, fog device takes most of computational cost in encryption and decryption phase. The computational cost of the receiver and sender can be reduced. Moreover, the private key of the user is generated by multi-authority which can enhance the security of data. The analysis of security and performance shows that our proposed scheme proves to be effective and secure.

Gollamudi, Anitha, Chong, Stephen, Arden, Owen.  2019.  Information Flow Control for Distributed Trusted Execution Environments. 2019 IEEE 32nd Computer Security Foundations Symposium (CSF). :304–30414.

Distributed applications cannot assume that their security policies will be enforced on untrusted hosts. Trusted execution environments (TEEs) combined with cryptographic mechanisms enable execution of known code on an untrusted host and the exchange of confidential and authenticated messages with it. TEEs do not, however, establish the trustworthiness of code executing in a TEE. Thus, developing secure applications using TEEs requires specialized expertise and careful auditing. This paper presents DFLATE, a core security calculus for distributed applications with TEEs. DFLATE offers high-level abstractions that reflect both the guarantees and limitations of the underlying security mechanisms they are based on. The accuracy of these abstractions is exhibited by asymmetry between confidentiality and integrity in our formal results: DFLATE enforces a strong form of noninterference for confidentiality, but only a weak form for integrity. This reflects the asymmetry of the security guarantees of a TEE: a malicious host cannot access secrets in the TEE or modify its contents, but they can suppress or manipulate the sequence of its inputs and outputs. Therefore DFLATE cannot protect against the suppression of high-integrity messages, but when these messages are delivered, their contents cannot have been influenced by an attacker.

Wang, Ti, Ma, Hui, Zhou, Yongbin, Zhang, Rui, Song, Zishuai.  2019.  Fully Accountable Data Sharing for Pay-As-You-Go Cloud Scenes. IEEE Transactions on Dependable and Secure Computing. :1–1.
Many enterprises and individuals prefer to outsource data to public cloud via various pricing approaches. One of the most widely-used approaches is the pay-as-you-go model, where the data owner hires public cloud to share data with data consumers, and only pays for the actually consumed services. To realize controllable and secure data sharing, ciphertext-policy attribute-based encryption (CP-ABE) is a suitable solution, which can provide fine-grained access control and encryption functionalities simultaneously. But there are some serious challenges when applying CP-ABE in pay-as-you-go. Firstly, the decryption cost in ABE is too heavy for data consumers. Secondly, ABE ciphertexts probably suffer distributed denial of services (DDoS) attacks, but there is no solution that can eliminate the security risk. At last, the data owner should audit resource consumption to guarantee the transparency of charge, while the existing method is inefficient. In this work, we propose a general construction named fully accountable ABE (FA-ABE), which simultaneously solves all the challenges by supporting all-sided accountability in the pay-as-you-go model. We formally define the security model and prove the security in the standard model. Also, we implement an instantiate construction with the self-developed library libabe. The experiment results indicate the efficiency and practicality of our construction.
2020-01-07
Rao, Deepthi, Kumar, D.V.N. Siva, Thilagam, P. Santhi.  2018.  An Efficient Multi-User Searchable Encryption Scheme without Query Transformation over Outsourced Encrypted Data. 2018 9th IFIP International Conference on New Technologies, Mobility and Security (NTMS). :1-4.

Searchable Encryption (SE) schemes provide security and privacy to the cloud data. The existing SE approaches enable multiple users to perform search operation by using various schemes like Broadcast Encryption (BE), Attribute-Based Encryption (ABE), etc. However, these schemes do not allow multiple users to perform the search operation over the encrypted data of multiple owners. Some SE schemes involve a Proxy Server (PS) that allow multiple users to perform the search operation. However, these approaches incur huge computational burden on PS due to the repeated encryption of the user queries for transformation purpose so as to ensure that users' query is searchable over the encrypted data of multiple owners. Hence, to eliminate this computational burden on PS, this paper proposes a secure proxy server approach that performs the search operation without transforming the user queries. This approach also returns the top-k relevant documents to the user queries by using Euclidean distance similarity approach. Based on the experimental study, this approach is efficient with respect to search time and accuracy.