Cryptanalysis of fruit-80, craft and cham lightweight symmetric-key cryptographic primitives

In this modern era, computers are getting more lightweight and smaller in size. This advancement has caused lightweight cryptography becomes a prevalent trend. However, lightweight primitives may present undiscovered vulnerabilities that threaten the security and privacy of communications. In this thesis, cryptanalysis on selected lightweight symmetric-key ciphers, which are the Fruit-80 stream cipher, the CRAFT block cipher and the CHAM family of block ciphers, are presented. The objective of this thesis is to study the security level of selected lightweight ciphers, namely Fruit-80, CRAFT and CHAM, to apply cryptanalytic techniques on the selected ciphers, and to study the impact of the cryptanalytic techniques on these three ciphers. The research framework for cryptanalysis of block ciphers and stream ciphers are discussed, which is divided into five phases, namely, literature review, determining research requirements, evaluation of cipher’s properties, result assessment and documentation. First, the security of the Fruit-80 stream cipher is investigated with regard to the existence of slid key-IV pairs (also known as slid pairs). By using a Mixed Integer Linear Programming (MILP) solver, slid pairs can be generated trivially. The result shows that slid pairs do exist in Fruit-80, which also implies the existence of more than one key-IV pair that can generate an identical keystream. Next, security evaluation on the CRAFT block cipher against side channel cube attack is also presented in this thesis. For most of the secret keys, by reading the Hamming weight leakage after the first round and the second round of CRAFT, the whole secret key can be recovered within a practical time. This attack shows that CRAFT does not necessarily provide protection for all side channel attacks although the designers of CRAFT claims that CRAFT is secure against differential fault attack, which is also a side channel attack. Finally, the security evaluation of CHAM from the perspective of its key scheduling is also analysed. The correlation between master key difference and round key difference is measured. It is found that the number of different master key bits is almost proportional to the number of different round key bits in all CHAM block ciphers, suggesting that the key scheduling used in CHAM family of block ciphers has a weak diffusion. The key scheduling of CHAM is also evaluated for existence of repeated differential pattern. The results show that all CHAM variants possess strong repeated differential patterns. This thesis provides insights to future studies such as analysis in slid pairs of the Fruit and Fruit-128 stream ciphers, full key recovery by side-channel attacks on the CRAFT block cipher, and related-key cryptanalysis on the CHAM block ciphers based on their repeated differential patterns

Slid Pairs of the Fruit-80 Stream Cipher

Fruit is a small-state stream cipher designed for securing communications among resource-constrained devices. The design of Fruit was first known to the public in 2016. It was later improved as Fruit-80 in 2018 and becomes the latest and final version among all versions of the Fruit stream ciphers. In this paper, we analyze the Fruit-80 stream cipher. We found that Fruit-80 generates identical keystreams from certain two distinct pairs of key and IV. Such pair of key and IV pairs is known as a slid pair. Moreover, we discover that when two pairs of key and IV fulfill specific characteristics, they will generate identical keystreams. This shows that slid pairs do not always exist arbitrarily in Fruit-80. We define specific rules which are equivalent to the characteristics. Using the defined rules, we are able to automate the searching process using an MILP solver, which makes searching of the slid pairs trivial

Path Planning for Underactuated Dubins Micro-robots Using Switching Control

In this paper, we develop an optimal path planning strategy for under-actuated Dubins micro-robots. Such robots are non-holonomic robots constrained to move along circular paths of fixed curvature clockwise or counter-clockwise. Our objective is to investigate the coverage and optimal path problems, as well as multi-robot cooperation, for a switching control scheme. Our methods are based on elementary geometry and optimal control techniques. The results in this paper show that the trajectories of micro-robots can cover the entire two-dimensional plane, and that the proposed switching control scheme allows multiple robots to cooperate. In addition, we deduce the minimum-time path under the switching control scheme by converting the robot model into the traditional Dubins vehicle model

Key-dependent side-channel cube attack on CRAFT

CRAFT is a tweakable block cipher introduced in 2019 that aims to provide strong protection against differential fault analysis. In this paper, we show that CRAFT is vulnerable to side-channel cube attacks. We apply side-channel cube attacks to CRAFT with the Hamming weight leakage assumption. We found that the first half of the secret key can be recovered from the Hamming weight leakage after the first round. Next, using the recovered key bits, we continue our attack to recover the second half of the secret key. We show that the set of equations that are solvable varies depending on the value of the key bits. Our result shows that 99.90% of the key space can be fully recovered within a practical time

Decision aids to improve informed decision-making in pregnancy care: a systematic review

Rapid development in health care has resulted in an increasing number of screening and treatment options. Consequently, there is an urgency to provide people with relevant information about benefits and risks of healthcare options in an unbiased way. Decision aids help people to make decisions by providing unbiased non-directive research evidence about all treatment options. To determine the effectiveness of decision aids to improve informed decision making in pregnancy care. We searched MEDLINE (1953-2011), EMBASE (1980-2011), CENTRAL (CENTRAL, the Cochrane Library; 2011, Issue 4), Psycinfo (1806-2011) and Research Registers of ongoing trials (www.clinicaltrials.gov, www.controlled-trials.com). We included randomised controlled trials comparing decision aids in addition to standard care. The study population needed to be pregnant women making actual decisions concerning their pregnancy. Two independent researchers extracted data on quality of the randomised controlled trial (GRADE criteria), quality of the decision aid (IPDAS criteria), and outcome measures. Data analysis was undertaken by assessing group differences at first follow up after the interventions. Ten randomised controlled trials could be included. Pooled analyses showed that decision aids significantly increased knowledge, (weighted mean difference 11.06, 95% confidence interval 4.85-17.27), decreased decisional conflict scores (weighted mean difference -3.66, 95% confidence interval -6.65 to -0.68) and decreased anxiety (weighted mean difference -1.56, 95% confidence interval -2.75 to -0.43). Our systematic review showed the positive effect of decision aids on informed decision making in pregnancy care. Future studies should focus on increasing the uptake of decision aids in clinical practice by identifying barriers and facilitators to implementatio

Rapid hepatic clearance of full length CCN-2/CTGF: a putative role for LRP1-mediated endocytosis

This is the final version. Available on open access from Springer via the DOI in this record.CCN-2 (connective tissue growth factor; CTGF) is a key factor in fibrosis. Plasma CCN-2 has biomarker potential in numerous fibrotic disorders, but it is unknown which pathophysiological factors determine plasma CCN-2 levels. The proteolytic amino-terminal fragment of CCN-2 is primarily eliminated by the kidney. Here, we investigated elimination and distribution profiles of full length CCN-2 by intravenous administration of recombinant CCN-2 to rodents. After bolus injection in mice, we observed a large initial distribution volume (454 mL/kg) and a fast initial clearance (120 mL/kg/min). Immunosorbent assay and immunostaining showed that CCN-2 distributed mainly to the liver and was taken up by hepatocytes. Steady state clearance in rats, determined by continuous infusion of CCN-2, was fast (45 mL/kg/min). Renal CCN-2 clearance, determined by arterial and renal vein sampling, accounted for only 12 % of total clearance. Co-infusion of CCN-2 with receptor-associated protein (RAP), an antagonist of LDL-receptor family proteins, showed that RAP prolonged CCN-2 half-life and completely prevented CCN-2 internalization by hepatocytes. This suggests that hepatic uptake of CCN-2 is mediated by a RAP-sensitive mechanism most likely involving LRP1, a member of the LDL-receptor family involved in hepatic clearance of various plasma proteins. Surface plasmon resonance binding studies confirmed that CCN-2 is an LRP1 ligand. Co-infusion of CCN-2 with an excess of the heparan sulphate-binding protamine lowered the large initial distribution volume of CCN-2 by 88 % and reduced interstitial staining of CCN-2, suggesting binding of CCN-2 to heparan sulphate proteoglycans (HSPGs). Protamine did not affect clearance rate, indicating that RAP-sensitive clearance of CCN-2 is HSPG independent. In conclusion, unlike its amino-terminal fragment which is cleared by the kidney, full length CCN-2 is primarily eliminated by the liver via a fast RAP-sensitive, probably LRP1-dependent pathway.FibroGen, Inc

Maternal blood pressure during pregnancy and early childhood blood pressures in the offspring

10.1097/MD.0000000000001981Medicine94451-9GUSTO (Growing up towards Healthy Outcomes

On-demand semiconductor single-photon source with near-unity indistinguishability

Single photon sources based on semiconductor quantum dots offer distinct advantages for quantum information, including a scalable solid-state platform, ultrabrightness, and interconnectivity with matter qubits. A key prerequisite for their use in optical quantum computing and solid-state networks is a high level of efficiency and indistinguishability. Pulsed resonance fluorescence (RF) has been anticipated as the optimum condition for the deterministic generation of high-quality photons with vanishing effects of dephasing. Here, we generate pulsed RF single photons on demand from a single, microcavity-embedded quantum dot under s-shell excitation with 3-ps laser pulses. The pi-pulse excited RF photons have less than 0.3% background contributions and a vanishing two-photon emission probability. Non-postselective Hong-Ou-Mandel interference between two successively emitted photons is observed with a visibility of 0.97(2), comparable to trapped atoms and ions. Two single photons are further used to implement a high-fidelity quantum controlled-NOT gate.Comment: 11 pages, 11 figure

Experimental violation of the Leggett-Garg inequality under decoherence

Despite the great success of quantum mechanics, questions regarding its application still exist and the boundary between quantum and classical mechanics remains unclear. Based on the philosophical assumptions of macrorealism and noninvasive measurability, Leggett and Garg devised a series of inequalities (LG inequalities) involving a single system with a set of measurements at different times. Introduced as the Bell inequalities in time, the violation of LG inequalities excludes the hidden-variable description based on the above two assumptions. We experimentally investigated the single photon LG inequalities under decoherence simulated by birefringent media. These generalized LG inequalities test the evolution trajectory of the photon and are shown to be maximally violated in a coherent evolution process. The violation of LG inequalities becomes weaker with the increase of interaction time in the environment. The ability to violate the LG inequalities can be used to set a boundary of the classical realistic description