Biblio

Network-on-Chip (NoC) is widely used as an efficient communication architecture in multi-core and many-core System-on-Chips (SoCs). However, the shared communication resources in NoCs, e.g., channels, buffers, and routers might be used to conduct attacks compromising the security of NoC-based SoCs. Almost all of the proposed encryption-based protection methods in the literature need to leave some parts of the packet unencrypted to allow the routers to process/forward packets accordingly. This uncovers the source/destination information of the packet to malicious routers, which can be used in various attacks. In this paper, we propose the idea of secure anonymous routing with minimal hardware overhead to hide the source/destination information while exchanging secure information over the network. The proposed method uses a novel source-routing algorithm that works with encrypted destination addresses and prevents malicious routers from discovering the source/destination of secure packets. To support our proposal, we have designed and implemented a new NoC architecture that works with encrypted addresses. The conducted hardware evaluations show that the proposed security solution combats the security threats at an affordable cost of 1% area and 10% power overheads chip-wide.

In this paper, we propose a new provably secure cryptosystem for two party communication that provides security in the face of new technological breakthroughs. Most of the practical cryptosystems in use today can be breached in the future with new sophisticated methods. This jeopardizes the security of older but highly confidential messages. Our protocol is based on the bounded storage model first introduced in [1]. The protocol is secure as long as there is bound on the storage, however large it may be. We also suggest methods to extend the protocol to unbounded storage models where access to adversary is limited. Our protocol is a substantial improvement over previously known protocols and uses short key and optimal number of public random bits size of which is independent of message length. The smaller and constant length of key and public random string makes the scheme more practical. The protocol generates key using elements of the additive group \$\textbackslashtextbackslashmathbbZ\_\textbackslashtextbackslashmathrmn\$. Our protocol is very generalized and the protocol in [1] is a special case of our protocol. Our protocol is a step forward in making provably secure cryptosystems practical. An important open problem raised in [2] was designing an algorithm with short key and size of public random string \$O(\textbackslashtextbackslashmathcalB)\$ where \$\textbackslashtextbackslashmathcalB\$ bounds the storage of adversary. Our protocol satisfies the conditions and is easy to implement.

Mobile payment protocols have attracted widespread attention over the past decade, due to advancements in digital technology. The use of these protocols in online industries can dramatically improve the quality of online services. However, the central issue of concern when utilizing these types of systems is their accountability, which ensures trust between the parties involved in payment transactions. It is, therefore, vital for researchers to investigate how to handle the accountability of mobile payment protocols. In this research, we introduce a secure mobile payment protocol to overcome this problem. Our payment protocol combines all the necessary security features, such as confidentiality, integrity, authentication, and authorization that are required to build trust among parties. In other words, is the properties of mutual authentication and non-repudiation are ensured, thus providing accountability. Our approach can resolve any conflicts that may arise in payment transactions between parties. To prove that the proposed protocol is correct and complete, we use the Scyther and AVISPA tools to verify our approach formally.

This paper deals with a problem that arises in vertical composition of protocols, i.e., when a channel protocol is used to encrypt and transport arbitrary data from an application protocol that uses the channel. Our work proves that we can verify that the channel protocol ensures its security goals independent of a particular application. More in detail, we build a general paradigm to express vertical composition of an application protocol and a channel protocol, and we give a transformation of the channel protocol where the application payload messages are replaced by abstract constants in a particular way that is feasible for standard automated verification tools. We prove that this transformation is sound for a large class of channel and application protocols. The requirements that channel and application have to satisfy for the vertical composition are all of an easy-to-check syntactic nature.

Blockchain-based cryptocurrencies offer an appealing alternative to Fiat currencies, due to their decentralized and borderless nature. However the decentralized settings make the authentication process more challenging: Standard cryptographic methods often rely on the ability of users to reliably store a (large) secret information. What happens if one user's key is lost or stolen? Blockchain systems lack of fallback mechanisms that allow one to recover from such an event, whereas the traditional banking system has developed and deploys quite effective solutions. In this work, we develop new cryptographic techniques to integrate security policies (developed in the traditional banking domain) in the blockchain settings. We propose a system where a smart contract is given the custody of the user's funds and has the ability to invoke a two-factor authentication (2FA) procedure in case of an exceptional event (e.g., a particularly large transaction or a key recovery request). To enable this, the owner of the account secret-shares the answers of some security questions among a committee of users. When the 2FA mechanism is triggered, the committee members can provide the smart contract with enough information to check whether an attempt was successful, and nothing more. We then design a protocol that securely and efficiently implements such a functionality: The protocol is round-optimal, is robust to the corruption of a subset of committee members, supports low-entropy secrets, and is concretely efficient. As a stepping stone towards the design of this protocol, we introduce a new threshold homomorphic encryption scheme for linear predicates from bilinear maps, which might be of independent interest. To substantiate the practicality of our approach, we implement the above protocol as a smart contract in Ethereum and show that it can be used today as an additional safeguard for suspicious transactions, at minimal added cost. We also implement a second scheme where the smart contract additionally requests a signature from a physical hardware token, whose verification key is registered upfront by the owner of the funds. We show how to integrate the widely used universal two-factor authentication (U2F) tokens in blockchain environments, thus enabling the deployment of our system with available hardware.

Observational non-interference (ONI) is a generic information-flow policy for side-channel leakage. Informally, a program is ONI-secure if observing program leakage during execution does not reveal any information about secrets. Formally, ONI is parametrized by a leakage function l, and different instances of ONI can be recovered through different instantiations of l. One popular instance of ONI is the cryptographic constant-time (CCT) policy, which is widely used in cryptographic libraries to protect against timing and cache attacks. Informally, a program is CCT-secure if it does not branch on secrets and does not perform secret-dependent memory accesses. Another instance of ONI is the constant-resource (CR) policy, a relaxation of the CCT policy which is used in Amazon's s2n implementation of TLS and in several other security applications. Informally, a program is CR-secure if its cost (modelled by a tick operator over an arbitrary semi-group) does not depend on secrets.In this paper, we consider the problem of preserving ONI by compilation. Prior work on the preservation of the CCT policy develops proof techniques for showing that main compiler optimisations preserve the CCT policy. However, these proof techniques critically rely on the fact that the semi-group used for modelling leakage satisfies the property: l1+ l1' = l2+l2'$\Rightarrow$l1=l2$\wedge$ l1' = l2' Unfortunately, this non-cancelling property fails for the CR policy, because its underlying semi-group is ($\backslash$mathbbN, +) and it is currently not known how to extend existing techniques to policies that do not satisfy non-cancellation.We propose a methodology for proving the preservation of the CR policy during a program transformation. We present an implementation of some elementary compiler passes, and apply the methodology to prove the preservation of these passes. Our results have been mechanically verified using the Coq proof assistant.

Mobile Ad-hoc Networks (MANET) is an autonomous network consisting of movable devices that can form a network using wireless media. MANET routing protocols can be used for selecting an efficient and shortest path for data transmission between nodes in a smart environment formed by the Internet of Things (IoT). Networking in such MANET-enabled IoT system is based on the routing protocols of MANET, data sensing from things, and data handling and processing using IoT. This paper studies proactive approach-based secure routing protocols for MANET-enabled IoT and analyses these protocols to identify security issues in it. Since this fusion network is resource-constrained in nature, each of the studied protocol is evaluated to check if it is lightweight or not. Also, the solution to defend against active attacks in this network is discussed.

Security plays a paradigmatic role in the area of networking. The main goal of security is to protect these networks which contains confidential data against various kinds of attacks. By changing parameters like key size, increasing the rounds of iteration and finally using confusion box as the S-box, the strength of the cryptographic algorithms can be incremented. By using the Data Encryption Standard (DES), the images can be secured with the help of Dynamic S-boxes. Each of these 8 S-boxes contain 64 elements. Each row contains elements in the range 0–15 and are unique. Our proposed system generates these S-boxes dynamically depending on the key. The evaluation of this Dynamic S-box and DES shows much fruitful results over factors like Non-linearity, Strict Avalanche criterion, Balance, memory and time required for implementation using images.

High throughput of crypto circuit is critical for many high performance security applications. The proposed SM3 circuit design breaks the inherent limitation of the conventional algorithm flow by removing the "blocking point" on the critical path, and reorganizes the algebraic structure by adding four parallel compensation operations. In addition, the round expansion architecture, CSA (Carry Save Adder) and pre-calculation are also used in this design. Due to the optimization at both the algorithm level and the circuit level, the synthesized circuit of this design can reach maximum 415MHz operating clock frequency and 6.4Gbps throughput with SMIC 40nm high performance technology. Compared with the conventional implementation method, the throughput performance of the proposed SM3 circuit increases by 97.5% and the chip area of SM3 algorithm area is only increased by 16.2%.

With the rapid advancements in information technology, data security has become an indispensable component. Cryptography performs a significant role in establishing information security. Computational problems have been utilized extensively by cryptographers to construct digital signature schemes. Digital signature schemes offer security services such as confidentiality, authenticity, integrity, and non-repudiation of a message. This paper proposes a modification of the Dilithium signature scheme that is secure against unforgeability attack based on the hardness of lattice problems such as Learning With Errors and Short Integer Solution over lattices. Using the rejection sampling technique, data is sampled from a uniform distribution to generate keys that are expanded into a matrix. The keys are hashed and signed by the sender to generate a message, which is then accepted by the receiver upon verification. Finally, the security analysis for the proposed signature scheme is provided with a strong emphasis on the security of the secret key. We prove that the attacker cannot forge a signature on a message, and recommended parameters are proposed.

As the rapid development of information technology and networks, there have been several new challenges to data security. For security needs in the process of data transmission and storage, the data security protection mechanism based on SM algorithm is studied. In addition, data cryptographic security protection system model composed of cryptographic infrastructure, cryptographic service nodes and cryptographic modules is proposed. As the core of the mechanism, SM algorithm not only brings about efficient data encryption and decryption, but ensures the security, integrity and non-repudiation of data transmission and storage. Secure and controllable key management is implemented by this model, which provides easy-to-expandable cryptographic services, and brings efficient cryptographic capabilities applicable for multiple scenarios.

Structural analysis is the study of finding component functions for a given function. In this paper, we proceed with structural analysis of structures consisting of the S (nonlinear Substitution) layer and the A (Affine or linear) layer. Our main interest is the S1AS2 structure with different substitution layers and large input/output sizes. The purpose of our structural analysis is to find the functionally equivalent oracle F* and its component functions for a given encryption oracle F(= S2 ∘ A ∘ S1). As a result, we can construct the decryption oracle F*−1 explicitly and break the one-wayness of the building blocks used in a White-box implementation. Our attack consists of two steps: S layer recovery using multiset properties and A layer recovery using differential properties. We present the attack algorithm for each step and estimate the time complexity. Finally, we discuss the applicability of S1AS2 structural analysis in a White-box Cryptography environment.

There will be a fatal risk when the submitted file is stolen or altered by someone else during the file submission process. To maintain the security of sending files from sender to recipient, it is necessary to secure files. The science of maintaining the security of messages is called cryptography. The authors were interested in examining the Three Pass Protocol scheme in this study because it eliminated the necessity for sender and receiver to exchange keys during the operation of the Hill Cipher 3x3 algorithm. The Hill Cipher algorithm was chosen because the key has an inverse and matrix-shaped value. Then the key used must be checked whether it has a GCD (Greatest Common Divisor) grade 1 or not and will be shaped like matrix. System implementation using the Java programming language using Android Studio software. System testing is done by encrypting and decrypting files. System testing results illustrate that the process encryption and decryption by the sender is faster than the recipient, so the encryption and decryption time needed directly proportional; the larger the pixel size of the image on the image file used, the longer it takes.

Explainable Artificial Intelligence (XAI) generates explanations which are used by regulators to audit the responsibility in case of any catastrophic failure. These explanations are currently stored in centralized systems. However, due to lack of security and traceability in centralized systems, the respective owner may temper the explanations for his convenience in order to avoid any penalty. Nowadays, Blockchain has emerged as one of the promising technologies that might overcome the security limitations. Hence, in this paper, we propose a novel Blockchain based framework for proof-of-authenticity pertaining to XAI decisions. The framework stores the explanations in InterPlanetary File System (IPFS) due to storage limitations of Ethereum Blockchain. Further, a Smart Contract is designed and deployed in order to supervise the storage and retrieval of explanations from Ethereum Blockchain. Furthermore, to induce cryptographic security in the network, an explanation's hash is calculated and stored in Blockchain too. Lastly, we perform the cost and security analysis of our proposed system.

The construction of the power Internet of Things has led various terminals to access the corporate network on a large scale. The internal and external business interaction and data exchange are more extensive. The current security protection system is based on border isolation protection. This is difficult to meet the needs of the power Internet of Things connection and open shared services. This paper studies the application scheme of the ``zero trust'' typical business scenario of the power Internet of Things with ``Continuous Identity Authentication and Dynamic Access Control'' as the core, and designs the power internet security protection architecture based on zero trust.

Zero Trust security model permits to secure cloud native applications while encrypting all network communication, authenticating, and authorizing every request. The service mesh can enable Zero Trust using a side-car proxy without changes to the application code. To the best of our knowledge, no previous work has provided a performance analysis of Zero Trust in a multi-cloud environment. This paper proposes a multi-cloud framework and a testing workflow to analyse performance of the data plane under load and the impact on the control plane, when Zero Trust is enabled. The results of preliminary tests show that Istio has reduced latency variability in responding to sequential HTTP requests. Results also reveal that the overall CPU and memory usage can increase based on service mesh configuration and the cloud environment.

Random K-out graphs, denoted \$$\backslash$mathbbH(n;K)\$, are generated by each of the \$n\$ nodes drawing \$K\$ out-edges towards \$K\$ distinct nodes selected uniformly at random, and then ignoring the orientation of the arcs. Recently, random K-out graphs have been used in applications as diverse as random (pairwise) key predistribution in ad-hoc networks, anonymous message routing in crypto-currency networks, and differentially-private federated averaging. In many applications, connectivity of the random K-out graph when some of its nodes are dishonest, have failed, or have been captured is of practical interest. We provide a comprehensive set of results on the connectivity and giant component size of \$$\backslash$mathbbH(n;K\_n,$\backslash$gamma\_n)\$, i.e., random K-out graph when \textsubscriptn of its nodes, selected uniformly at random, are deleted. First, we derive conditions for \textsubscriptn and \$n\$ that ensure, with high probability (whp), the connectivity of the remaining graph when the number of deleted nodes is \$$\backslash$gamma\_n=Ømega(n)\$ and \$$\backslash$gamma\_n=o(n)\$, respectively. Next, we derive conditions for \$$\backslash$mathbbH(n;K\_n, $\backslash$gamma\_n)\$ to have a giant component, i.e., a connected subgraph with \$Ømega(n)\$ nodes, whp. This is also done for different scalings of \textsubscriptn and upper bounds are provided for the number of nodes outside the giant component. Simulation results are presented to validate the usefulness of the results in the finite node regime.

Anonymous Zether, proposed by Bünz, Agrawal, Zamani, and Boneh (FC'20), is a private payment design whose wallets demand little bandwidth and need not remain online; this unique property makes it a compelling choice for resource-constrained devices. In this work, we describe an efficient construction of Anonymous Zether. Our protocol features proofs which grow only logarithmically in the size of the "anonymity sets" used, improving upon the linear growth attained by prior efforts. It also features competitive transaction sizes in practice (on the order of 3 kilobytes).Our central tool is a new family of extensions to Groth and Kohlweiss's one-out-of-many proofs (Eurocrypt 2015), which efficiently prove statements about many messages among a list of commitments. These extensions prove knowledge of a secret subset of a public list, and assert that the commitments in the subset satisfy certain properties (expressed as linear equations). Remarkably, our communication remains logarithmic; our computation increases only by a logarithmic multiplicative factor. This technique is likely to be of independent interest.We present an open-source, Ethereum-based implementation of our Anonymous Zether construction.

This paper proposes an anonymity based mechanism for providing privacy in IoT environment. Proposed scheme allows IoT entities to anonymously interacting and authenticating with each other, or even proving that they have trustworthy relationship without disclosing their identities. Authentication is based on an anonymous certificates mechanism where interacting IoT entities could unlinkably prove possession of a valid certificate without revealing any incorporated identity-related information, thereby preserving their privacy and thwarting tracking and profiling attacks. Through a security analysis, we demonstrate the reliability of our solution.

This paper presents a decentralized messaging system based on blockchain technology. This system allows their users to securely send and receive digital messages in the network. Since the messages stored in a conventional blockchain could be easily read by everyone in the network, under the proposed approach these messages are previously encrypted using public-key cryptography, while the sender and recipient remain anonymous. The proposed system incorporates a browser-based user interface that enable their users to interact seamlessly in a peer-to-peer fashion.

A promising paradigm in protocol design is to hold parties accountable for misbehavior, instead of postulating that they are trustworthy. Recent approaches in defining this property, called accountability, characterized malicious behavior as a deviation from the protocol that causes a violation of the desired security property, but did so under the assumption that all deviating parties are controlled by a single, centralized adversary. In this work, we investigate the setting where multiple parties can deviate with or without coordination in a variant of the applied-π calculus.We first demonstrate that, under realistic assumptions, it is impossible to determine all misbehaving parties; however, we show that accountability can be relaxed to exclude causal dependencies that arise from the behavior of deviating parties, and not from the protocol as specified. We map out the design space for the relaxation, point out protocol classes separating these notions and define conditions under which we can guarantee fairness and completeness. Most importantly, we discover under which circumstances it is correct to consider accountability in the single-adversary setting, where this property can be verified with off-the-shelf protocol verification tools.

In this paper, we present FireBugs for Finding and Repairing Bugs based on security patterns. For the common misuse patterns of cryptography APIs (crypto APIs), we encode common cryptography rules into the pattern representations for bug detection and program repair regarding cryptography rule violations. In the evaluation, we conducted a case study to assess the bug detection capability by applying FireBugs to datasets mined from both open source and commercial projects. Also, we conducted a user study with professional software engineers at Mutual of Omaha Insurance Company to estimate the program repair capability. This evaluation showed that FireBugs can help professional engineers develop various cryptographic requirements in a resilient application.

Cryptographic (crypto) algorithms are the essential ingredients of all secure systems: crypto hash functions and encryption algorithms, for example, can guarantee properties such as integrity and confidentiality. Developers, however, can misuse the application programming interfaces (API) of such algorithms by using constant keys and weak passwords. This paper presents CRYLOGGER, the first open-source tool to detect crypto misuses dynamically. CRYLOGGER logs the parameters that are passed to the crypto APIs during the execution and checks their legitimacy offline by using a list of crypto rules. We compared CRYLOGGER with CryptoGuard, one of the most effective static tools to detect crypto misuses. We show that our tool complements the results of CryptoGuard, making the case for combining static and dynamic approaches. We analyzed 1780 popular Android apps downloaded from the Google Play Store to show that CRYLOGGER can detect crypto misuses on thousands of apps dynamically and automatically. We reverse-engineered 28 Android apps and confirmed the issues flagged by CRYLOGGER. We also disclosed the most critical vulnerabilities to app developers and collected their feedback.

A recent research shows that 88 % of Android applications that use cryptographic APIs make at least one mistake. For this reason, several tools have been proposed to detect crypto API misuses, such as CryptoLint, CMA, and CogniCryptSAsT. However, these tools depend heavily on manually designed rules, which require much cryptographic knowledge and could be error-prone. In this paper, we propose an approach based on probabilistic models, namely, hidden Markov model and n-gram model, to analyzing crypto API usages in Android applications. The difficulty lies in that crypto APIs are sensitive to not only API orders, but also their arguments. To address this, we have created a dataset consisting of crypto API sequences with arguments, wherein symbolic execution is performed. Finally, we have also conducted some experiments on our models, which shows that ( i) our models are effective in capturing the usages, detecting and locating the misuses; (ii) our models perform better than the ones without symbolic execution, especially in misuse detection; and (iii) compared with CogniCryptSAsT, our models can detect several new misuses.

The exceptional attributes of impromptu network of being framework less, self-composed and unconstrained make the task more challenging to secure it. In mobile Ad-hoc network nodes reliant on one another for transmitting information, that make MANET helpless against different sorts of security attacks. These security attacks can be arranged as Passive and Active attacks. Wormhole is an Active attack and considered generally risky as it can make significant harm routing. Various secure routing mechanism has been created are based on cryptography mechanism, need pre-organized structure, centralized authority, or need external hardware, etc. These components are unreasonable due to restricted accessible assets in MANET. In this paper, we are proposing an effective trust-based mechanism based on the concept of Node to Node packet delay for the detection of the malevolent node of wormhole. The trust value of each node is calculated by observing the packet transaction among adjacent nodes and later this trust value is used for identification of malevolent node. Based on the trust values, further routing decisions and selecting a secured route can be perform.