Stream Cipher Research Articles

Lightweight cryptographic algorithms based on different model architectures: A systematic review and futuristic applications

SummaryLightweight cryptography is a rapidly developing research field. Its main goal is to provide security for devices with fewer resources. These limited‐resource devices implement reliable ciphers that use very little power and computation. The lightweight cipher should be built for high performance while using the fewest resources possible, such as memory and power. In this article, we compare block ciphers and several other stream ciphers based on criteria such as input size, output size, structure employed, key size, number of rounds, vulnerable attacks, chip area, gate equivalent, memory use, throughput, and security features. Moreover, this article provides a detailed analysis comparing all cryptographic algorithms and their use in day‐to‐day life activities. This paper also discusses some lightweight ciphers, stream ciphers, and hybrid ciphers. Moreover, it shows the cryptanalysis of some block ciphers like DES.

Security analysis of a QAM modulated quantum noise stream cipher under a correlation attack.

Quantum noise stream cipher where encrypted signals are masked by quantum noise and ASE noise provides a physical layer of security. It requires the transmitter and the receiver to share a stream cipher that is generated from a PRNG. Yet a correlation attack threatens its security due to the mathematical properties of PRNG. This paper discusses the security of QNSC system under correlation attacks. Our experiment results find that the security of the whole system depends on the cycle to refresh the seed key and the correlation between the incepted running key, original running key, and seed key. Furthermore, it is important to provide security for the QNSC system by maintaining low optical power. Besides, this new analytical method provides quantitative security analysis for a QNSC system under a correlation attack.

Encryption AXI Transaction Core for Enhanced FPGA Security

The current hot topic in cyber-security is not constrained to software layers. As attacks on electronic circuits have become more usual and dangerous, hardening digital System-on-Chips has become crucial. This article presents a novel electronic core to encrypt and decrypt data between two digital modules through an Advanced eXtensible Interface (AXI) connection. The core is compatible with AXI and is based on a Trivium stream cipher. Its implementation has been tested on a Zynq platform. The core prevents unauthorized data extraction by encrypting data on the fly. In addition, it takes up a small area—242 LUTs—and, as the core’s AXI to AXI path is fully combinational, it does not interfere with the system’s overall performance, with a maximum AXI clock frequency of 175 MHz.

A New Approach for Side Channel Analysis on Stream Ciphers and Related Constructions

Side Channel Analysis (SCA) is among the newly emerged threats to small scale devices performing a cryptographic operation. While such analysis is well studied against the block ciphers, we observe that the stream cipher counterpart is not that much explored. We propose novel modelling that can work with a number of stream ciphers and related constructions. We show practical state/key recovery attacks on the lightweight ciphers, LIZARD, PLANTLET and GRAIN-128-AEAD. We consider the software platform (where the Hamming weight leakage is available) as well as the hardware platform (where the Hamming distance leakage is available). Through the modelling of Satisfiability Modulo Theory (SMT), we show that the solution can be obtained in a matter of seconds in most cases. In a handful of cases, however, the entire state/key recovery is not feasible in a practical amount of time. For those cases, we show full recovery is possible when a small number of bits are guessed. We also study the effect of increasing/decreasing the number of keystream bits on the solution time. Following a number of literature, we initially assume the traces that are obtained are noiseless. Later, we show how an extension of our model can deal with the noisy traces (which is a more general assumption).

Novel lightweight video encryption method based on ChaCha20 stream cipher and hybrid chaotic map

<span lang="EN-US">In the recent years, an increasing demand for securing visual resource-constrained devices become a challenging problem due to the characteristics of these devices. Visual resource-constrained devices are suffered from limited storage space and lower power for computation such as wireless sensors, internet protocol (IP) camera and smart cards. Consequently, to support and preserve the video privacy in video surveillance system, lightweight security methods are required instead of the existing traditional encryption methods. In this paper, a new light weight stream cipher method is presented and investigated for video encryption based on hybrid chaotic map and ChaCha20 algorithm. Two chaotic maps are employed for keys generation process in order to achieve permutation and encryption tasks, respectively. The frames sequences are encrypted-decrypted based on symmetric scheme with assist of ChaCha20 algorithm. The proposed lightweight stream cipher method has been tested on several video samples to confirm suitability and validation in term of encryption–decryption procedures. The performance evaluation metrics include visual test, histogram analysis, information entropy, correlation analysis and differential analysis. From the experimental results, the proposed lightweight encryption method exhibited a higher security with lower computation time compared with state-of-the-art encryption methods.</span>

On the algebraic immunity of direct sum constructions

In this paper, we study sufficient conditions to improve the lower bound on the algebraic immunity of a direct sum of Boolean functions. We exhibit three properties on the component functions such that satisfying one of them is sufficient to ensure that the algebraic immunity of their direct sum exceeds the maximum of their algebraic immunities. These properties can be checked while computing the algebraic immunity and they allow to determine better the security provided by functions central in different cryptographic constructions such as stream ciphers, pseudorandom generators, and weak pseudorandom functions. We provide examples for each property and determine the exact algebraic immunity of candidate constructions.

SNOW3G Modified by using PLL Algorithms in Magic Cube

Thomas and Patrik are working on a stream cipher called SNOW 3G. In 2006, it was chosen as the centerpiece of a new set of confidentiality and integrity algorithms for the Universal Mobile Telecommunications System (UMTS). In 2008, Böhm published an article named "Statistical Evaluation of Stream Cipher SNOW 3G." He put the randomness of the SNOW 3G key stream generator to the test. As a randomness test tool, Böhm uses the NIST test statistics package, which consists of three kinds of tests: lengthy key stream data, short key stream data, and initialization vector data. Only the short key stream set of data failed eight random chance test results out of three kinds of tests, according to the report's findings. The SNOW 3G suggestions, he claims, fail due to a flaw with in cipher's initialization. In this paper, we use the PLL algorithm to modify the SNOW 3G algorithm for key initialization and generation keystream. We employ the same itself Böhm employed. The modify SNOW 3G algorithm exceed whole of the statistic exam in a experiment. The findings show that PLL has an effect on algorithm randomness. Index Terms— SNOW-3G, Stream Cipher, PLL Algorithms.

Research Status of Nonlinear Feedback Shift Register Based on Semi-Tensor Product

Nonlinear feedback shift registers (NFSRs) are the main components of stream ciphers and convolutional decoders. Recent years have seen an increase in the requirement for information security, which has sparked NFSR research. However, the NFSR study is very imperfect as a result of the lack of appropriate mathematical tools. Many scholars have discovered in recent years that the introduction of semi-tensor products (STP) of matrices can overcome this issue because STP can convert the NFSR into a quasi-linear form. As a result of STP, new NFSR research has emerged from a different angle. In view of this, in order to generalize the latest achievements of NFSRs based on STP and provide some directions for future development, the research results are summarized and sorted out, broadly including the modeling of NFSRs, the analysis of the structure of NFSRs, and the study of the properties of NFSRs.

DAC/ADC-free 4 × 12.9 Gbit/s 65,536-level quantum noise stream cipher secure optical WDM transmission based on delta-sigma modulation.

We propose and experimentally study a novel, to the best of our knowledge, quantum noise stream cipher (QNSC) secure transmission scheme based on the delta-sigma modulation (DSM) technique. The cooperation of the QNSC and DSM mechanisms makes it possible to transmit an ultrahigh-order encrypted signal in the non-return-to-zero (NRZ) on-off keying (OOK) format. The delivery of the NRZ OOK waveform over the fiber link allows us to send and receive signals using digital ports, instead of high-speed and high-resolution digital-to-analog converters (DACs) and analog-to-digital converters (ADCs)in conventional QNSC systems. Meanwhile, clock synchronization can be achieved by using a simple clock data recovery algorithm. The extra clock signal transmission link in conventional QNSC systems is no longer needed. The proposed scheme is also compatible with wavelength division multiplexing (WDM) systems. In this work, 4 × 12.9 Gbit/s plaintext is encrypted to a 65,536-level QNSC signal and then transmitted over a 10-km standard single-mode fiber. The transmitter and receiver are established by commercial 100G QSFP28 optical modules with clock data recovery. This proposed scheme can be easily deployed in commercial systems due to its minimalist implementation architecture and relatively low hardware cost.

LESCA: LightwEight Stream Cipher Algorithm for emerging systems

Recently, there has been a dire need for lightweight cryptographic solutions, which exhibit low computational complexity and require few resources. In this paper, we present LESCA, a novel dynamic key-dependent lightweight stream cipher, which consists of two main functions, a typical round function based on cryptographic primitives, and a function that updates these primitives. The update is performed in a selective (partial) manner while encrypting a block, and in full after each δ blocks/iterations. As such, LESCA consumes minimal resources and introduces a very low latency. The originality of this solution stems from the fact that the cryptographic primitives get updated even when encrypting the same message. Several performance and security tests were performed to confirm that the proposed cipher is robust and efficient, especially for limited devices and real-time applications. The proposed cipher achieves a high throughput; for example, when implemented on a Raspberry Pi (RPI4) device, LESCA provides an enhancement of at least 343% when compared to the Advanced Encryption Standard (AES), 72% over a recent one-round cipher scheme, and 43% improvement compared to a recent LORCA stream cipher that outperforms the Simon and Speck algorithms.

New Cryptanalysis of ZUC-256 Initialization Using Modular Differences

ZUC-256 is a stream cipher designed for 5G applications by the ZUC team. Together with AES-256 and SNOW-V, it is currently being under evaluation for standardized algorithms in 5G mobile telecommunications by Security Algorithms Group of Experts (SAGE). A notable feature of the round update function of ZUC-256 is that many operations are defined over different fields, which significantly increases the difficulty to analyze the algorithm.As a main contribution, with the tools of the modular difference, signed difference and XOR difference, we develop new techniques to carefully control the interactions between these operations defined over different fields. At first glance, our techniques are somewhat similar to those developed by Wang et al. for the MD-SHA hash family. However, as ZUC-256 is quite different from the MD-SHA hash family and its round function is much more complex, we are indeed dealing with different problems and overcoming new obstacles.As main results, by utilizing complex input differences, we can present the first distinguishing attacks on 31 out of 33 rounds of ZUC-256 and 30 out of 33 rounds of the new version of ZUC-256 called ZUC-256-v2 with low time and data complexities, respectively. These attacks target the initialization phase and work in the related-key model with weak keys. Moreover, with a novel IV-correcting technique, we show how to efficiently recover at least 16 key bits for 15-round ZUC-256 and 14-round ZUC-256-v2 in the related-key setting, respectively. It is unpredictable whether our attacks can be further extended to more rounds with more advanced techniques. Based on the current attacks, we believe that the full 33 initialization rounds provide marginal security.

Attacks on the Firekite Cipher

Firekite is a synchronous stream cipher using a pseudo-random number generator (PRNG) whose security is conjectured to rely on the hardness of the Learning Parity with Noise (LPN) problem. It is one of a few LPN-based symmetric encryption schemes, and it can be very efficiently implemented on a low-end SoC FPGA. The designers, Bogos, Korolija, Locher and Vaudenay, demonstrated appealing properties of Firekite, such as requiring only one source of cryptographically strong bits, small key size, high attainable throughput, and an estimate for the bit level security depending on the selected practical parameters.We propose distinguishing and key-recovery attacks on Firekite by exploiting the structural properties of its PRNG. We adopt several birthday-paradox techniques to show that a particular sum of Firekite’s output has a low Hamming weight with higher probability than the random case. We achieve the best distinguishing attacks with complexities 266.75 and 2106.75 for Firekite’s parameters corresponding to 80-bit and 128-bit security, respectively. By applying the distinguishing attacks and an additional algorithm we describe, one can also recover the secret matrix used in the Firekite PRNG, which is built from the secret key bits. This key recovery attack works on most large instances of Firekite parameters and has slightly larger complexity, for instance, 269.87 on the 80-bit security parameters n = 16,384, m = 216, k = 216.

Securing information using a proposed reliable chaos-based stream cipher: with real-time FPGA-based wireless connection implementation

In this paper, a robust chaos-based stream cipher (CBSC) is proposed. The novelty of this work is that it addresses all challenges confronting chaos-based cryptography. The PCBSC (proposed CBSC) has a robust synchronization circuit that mitigates the effect of channel noise, a perturbation block that overcomes the dynamical degradation, a robust encryption scheme, and an efficient control parameters’ generator that generates strong keys. According to the complexity evaluation, the improved chaotic map provides good statistical properties. This can be confirmed by the obtained high values of the statistical metrics (largest Lyapunov exponent, approximate entropy, permutation entropy, and sample entropy) used for the evaluation. According to the security analysis, the PCBSC has good security features and provides strong keys that ensure confusion property, as well as enough space to withstand brute-force attacks. On the other hand, the proposed encryption scheme proves its efficiency; the result of the differential attack clearly shows that the diffusion property is guaranteed. Additionally, the original images’ statistical properties are completely dispersed on the encrypted images. The obtained performance over noisy channels proves the synchronization circuit’s efficiency. When compared to other proposals, the PCBSC provides the best results. In addition, the PCBSC is implemented on an FPGA and evaluated in real-time over a wireless link.

High-Capacity Framework for Reversible Data Hiding in Encrypted Image Using Pixel Prediction and Entropy Encoding

While the existing reserving room before encryption (RRBE) based reversible data hiding in encrypted image (RDHEI) schemes can achieve decent embedding capacity, the capacity of the existing vacating room by encryption (VRBE) based schemes is relatively low. To address this issue, this paper proposes a generalized framework for high-capacity RDHEI for both the RRBE and VRBE cases. First, an efficient embedding room generation algorithm (ERGA) is designed to produce large embedding room using pixel prediction and entropy encoding. Then, we propose two RDHEI schemes, one for RRBE, another for VRBE. In the RRBE scenario, the image owner generates the embedding room with ERGA and encrypts the preprocessed image using stream cipher with two encryption keys. Then, the data hider locates the embedding room and embeds the additional encrypted data. In the VRBE scenario, the cover image is encrypted by an improved block modulation and permutation encryption algorithm, where the spatial redundancy in the plain-text image is greatly preserved. Then, the data hider applies ERGA on the encrypted image to generate the embedding room and conducts data embedding. For both schemes, receivers with different authentication keys can conduct either error-free data extraction or error-free image recovery. The experimental results show that the two proposed schemes outperform many state-of-the-art RDHEI schemes. Besides, they can ensure high security level, where the original image can be hardly discovered from the encrypted version before or after data hiding by unauthorized users.

DeepKeyGen: A Deep Learning-Based Stream Cipher Generator for Medical Image Encryption and Decryption.

The need for medical image encryption is increasingly pronounced, for example, to safeguard the privacy of the patients' medical imaging data. In this article, a novel deep learning-based key generation network (DeepKeyGen) is proposed as a stream cipher generator to generate the private key, which can then be used for encrypting and decrypting of medical images. In DeepKeyGen, the generative adversarial network (GAN) is adopted as the learning network to generate the private key. Furthermore, the transformation domain (that represents the "style" of the private key to be generated) is designed to guide the learning network to realize the private key generation process. The goal of DeepKeyGen is to learn the mapping relationship of how to transfer the initial image to the private key. We evaluate DeepKeyGen using three data sets, namely, the Montgomery County chest X-ray data set, the Ultrasonic Brachial Plexus data set, and the BraTS18 data set. The evaluation findings and security analysis show that the proposed key generation network can achieve a high-level security in generating the private key.

A Finite-Automaton Based Stream Cipher As a Quasigroup Based Cipher

In this paper we show that a recently published finite automaton stream cipher can be considered as a quasigroup based stream cipher. Some additional properties of the discussed cipher are also given.

A Secure Real-Time IoT Data Stream Based on Improved Compound Coupled Map Lattices

A secure data stream is important for the real time communications of Internet of Things (IoT). A stream cipher with the characteristics of simple and high speed is suitable in the secure communications of IoT for its security. Some stream ciphers based on coupled map lattices (CML) were proposed. However, the original coupled map lattice shows evidence of correlation between the contiguous points. In this paper, we present an improved CML with a counter to overcome the weakness. The proposed scheme has the advantage of simplicity and suits the resource constrained IoT environment. We implement the proposed improved CML and analyze the proposed ciphers against some attacks. For the balance performance analysis, the numbers of 0 and 1 in the keystream are almost balanced, and the difference rates show that the proposed schemes have high key sensitivity. Finally, we present some experimental results of statistical random number tests for the output keystreams. Under the pass rates of the statistical test of NIST SP800-22, the proposed ciphers with improved CML, and compound CML are at least 95% and 97%, respectively. All the pass rates of the proposed stream ciphers are 100% for the statistical test of FIPS PUB 140-1.

An algebraic attack to the Bluetooth stream cipher E0

In this paper we study the security of the Bluetooth stream cipher E0 from the viewpoint it is a “difference stream cipher”, that is, it is defined by a system of explicit difference equations over the finite field GF(2). This approach highlights some issues of the Bluetooth encryption such as the invertibility of its state transition map, a special set of 14 bits of its 132-bit state which when guessed implies linear equations among the other bits and finally a small number of spurious keys, with 83 guessed bits, which are compatible with a keystream of about 60 bits. Exploiting these issues, we implement an algebraic attack using Gröbner bases, SAT solvers and Binary Decision Diagrams. Testing activities suggest that the version based on Gröbner bases is the best one and it is able to attack E0 in about 279 seconds on an Intel i9 CPU. To the best of our knowledge, this work improves any previous attack based on a short keystream, hence fitting with Bluetooth specifications.

A Multi-Domain Embedding Framework for Robust Reversible Data Hiding Scheme in Encrypted Videos

For easier cloud management, reversible data hiding is performed in an encrypted domain to embed label information. However, the existing schemes are not robust and may cause the loss of label information during transmission. Enhancing robustness while maintaining reversibility in data hiding is a challenge. In this paper, a multi-domain embedding framework in encrypted videos is proposed to achieve both robustness and reversibility. In the framework, the multi-domain characteristic of encrypted video is fully used. The element for robust embedding is encrypted through Logistic chaotic scrambling, which is marked as element-I. To further improve robustness, the label information will be encoded with the Bose–Chaudhuri–Hocquenghem code. Then, the label information will be robustly embedded into element-I by modulating the amplitude of element-I, in which the auxiliary information is generated for lossless recovery of the element-I. The element for reversible embedding is marked as element-II, the sign of which will be encrypted by stream cipher. The auxiliary information will be reversibly embedded into element-Ⅱ through traditional histogram shifting. To verity the feasibility of the framework, an anti-recompression RDH-EV based on the framework is proposed. The experimental results show that the proposed scheme outperforms the current representative ones in terms of robustness, while achieving reversibility. In the proposed scheme, video encryption and data hiding are commutative and the original video bitstream can be recovered fully. These demonstrate the feasibility of the multi-domain embedding framework in encrypted videos.

A lightweight secure authentication approach based on stream ciphering for RFID-based Internet of Things

In this paper, a new lightweight RFID-based authentication approach is proposed that uses stream ciphering techniques to preserve privacy between legitimate components. The proposed approach uses various key-stream generators such as And2LFSR, Geffe, and majority-based to eliminate the inherent linearity of LFSRs and construct a non-linear Pseudo-Random Number Generators (PRNG). The informal security analysis indicates that the proposed approach provides forward security and resists eavesdropping, tag tracking, replay, cloning, and DoS attacks. Moreover, simulations conducted through Cooja tool illustrate the effect of generator polynomial degree and proposed combinational generators on BER. The BER of communications has been evaluated in different quantities of (Eb/N0), ranged between 1 and 10, using the proposed generators along with different error control techniques. In addition, evaluations indicate that the proposed approach outperforms in terms of computational cost, storage spaces, and communication cost. Furthermore, statistical analysis proves resistance of the proposed approach to guessing attacks.