bluuebunny/crossref_metadata_2025 huggingface dataset:
Adiantum: length-preserving encryption for entry-level processors
Authors: Crowley Paul , Biggers Eric
Published: November 2020

We present HBSH, a simple construction for tweakable length-preserving encryption which supports the fastest options for hashing and stream encryption for processors without AES or other crypto instructions, with a provable quadratic advantage bound. Our composition Adiantum uses NH, Poly1305, XChaCha12, and a single AES invocation. On an ARM Cortex-A7 processor, Adiantum decrypts 4096-byte messages at 10.6 cycles per byte, over five times faster than AES-256-XTS, with a constant-time implementation. We also define HPolyC which is simpler and has excellent key agility at 13.6 cycles per byte.
Nonlinear Approximations in Cryptanalysis Revisited
Authors: Beierle Christof , Canteaut Anne , Leander Gregor
Published: November 2020

This work studies deterministic and non-deterministic nonlinear approximations for cryptanalysis of block ciphers and cryptographic permutations and embeds it into the well-understood framework of linear cryptanalysis. For a deterministic (i.e., with correlation ±1) nonlinear approximation we show that in many cases, such a nonlinear approximation implies the existence of a highly-biased linear approximation. For non-deterministic nonlinear approximations, by transforming the cipher under consideration by conjugating each keyed instance with a fixed permutation, we are able to transfer many methods from linear cryptanalysis to the nonlinear case. Using this framework we in particular show that there exist ciphers for which some transformed versions are significantly weaker with regard to linear cryptanalysis than their original counterparts.
A General Proof Framework for Recent AES Distinguishers
Authors: Boura Christina , Canteaut Anne , Coggia Daniel
Published: November 2020

In this paper, a new framework is developed for proving and adapting the recently proposed multiple-of-8 property and mixture-differential distinguishers. The above properties are formulated as immediate consequences of an equivalence relation on the input pairs, under which the difference at the output of the round function is invariant. This approach provides a further understanding of these newly developed distinguishers. For example, it clearly shows that the branch number of the linear layer does not influence the validity of the property, on the contrary of what was previously believed. We further provide an extension of the mixture-differential distinguishers and multiple-of-8 property to any SPN and to a larger class of subspaces. These adapted properties can then be exhibited in a systematic way for other ciphers than the AES. We illustrate this with the examples of Midori, Klein, LED and Skinny.
Zero-Correlation Attacks on Tweakable Block Ciphers with Linear Tweakey Expansion
Authors: Ankele Ralph , Dobraunig Christoph , Guo Jian , Lambooij Eran , Leander Gregor , Todo Yosuke
Published: November 2020

The design and analysis of dedicated tweakable block ciphers is a quite recent and very active research field that provides an ongoing stream of new insights. For instance, results of Kranz, Leander, and Wiemer from FSE 2017 show that the addition of a tweak using a linear tweak schedule does not introduce new linear characteristics. In this paper, we consider – to the best of our knowledge – for the first time the effect of the tweak on zero-correlation linear cryptanalysis for ciphers that have a linear tweak schedule. It turns out that the tweak can often be used to get zero-correlation linear hulls covering more rounds compared to just searching zero-correlation linear hulls on the data-path of a cipher. Moreover, this also implies the existence of integral distinguishers on the same number of rounds. We have applied our technique on round reduced versions of Qarma, Mantis, and Skinny. As a result, we can present – to the best of our knowledge – the best attack (with respect to number of rounds) on a round-reduced variant of Qarma.
CRAFT: Lightweight Tweakable Block Cipher with Efficient Protection Against DFA Attacks
Authors: Beierle Christof , Leander Gregor , Moradi Amir , Rasoolzadeh Shahram
Published: November 2020

Traditionally, countermeasures against physical attacks are integrated into the implementation of cryptographic primitives after the algorithms have been designed for achieving a certain level of cryptanalytic security. This picture has been changed by the introduction of PICARO, ZORRO, and FIDES, where efficient protection against Side-Channel Analysis (SCA) attacks has been considered in their design. In this work we present the tweakable block cipher CRAFT: the efficient protection of its implementations against Differential Fault Analysis (DFA) attacks has been one of the main design criteria, while we provide strong bounds for its security in the related-tweak model. Considering the area footprint of round-based hardware implementations, CRAFT outperforms the other lightweight ciphers with the same state and key size. This holds not only for unprotected implementations but also when fault-detection facilities, side-channel protection, and their combination are integrated into the implementation. In addition to supporting a 64-bit tweak, CRAFT has the additional property that the circuit realizing the encryption can support the decryption functionality as well with very little area overhead.
A new SNOW stream cipher called SNOW-V
Authors: Ekdahl Patrik , Johansson Thomas , Maximov Alexander , Yang Jing
Published: November 2020

In this paper we are proposing a new member in the SNOW family of stream ciphers, called SNOW-V. The motivation is to meet an industry demand of very high speed encryption in a virtualized environment, something that can be expected to be relevant in a future 5G mobile communication system. We are revising the SNOW 3G architecture to be competitive in such a pure software environment, making use of both existing acceleration instructions for the AES encryption round function as well as the ability of modern CPUs to handle large vectors of integers (e.g. SIMD instructions). We have kept the general design from SNOW 3G, in terms of linear feedback shift register (LFSR) and Finite State Machine (FSM), but both entities are updated to better align with vectorized implementations. The LFSR part is new and operates 8 times the speed of the FSM. We have furthermore increased the total state size by using 128-bit registers in the FSM, we use the full AES encryption round function in the FSM update, and, finally, the initialization phase includes a masking with key bits at its end. The result is an algorithm generally much faster than AES-256 and with expected security not worse than AES-256.
Cryptanalysis of Plantlet
Authors: Banik Subhadeep , Barooti Khashayar , Isobe Takanori
Published: November 2020

Plantlet is a lightweight stream cipher designed by Mikhalev, Armknecht and Müller in IACR ToSC 2017. It has a Grain-like structure with two state registers of size 40 and 61 bits. In spite of this, the cipher does not seem to lose in security against generic Time-Memory-Data Tradeoff attacks due to the novelty of its design. The cipher uses a 80-bit secret key and a 90-bit IV. In this paper, we first present a key recovery attack on Plantlet that requires around 276.26 Plantlet encryptions. The attack leverages the fact that two internal states of Plantlet that differ in the 43rd LFSR location are guaranteed to produce keystream that are either equal or unequal in 45 locations with probability 1. Thus an attacker can with some probability guess that when 2 segments of keystream blocks possess the 45 bit difference just mentioned, they have been produced by two internal states that differ only in the 43rd LFSR location. Thereafter by solving a system of polynomial equations representing the keystream bits, the attacker can find the secret key if his guess was indeed correct, or reach some kind of contradiction if his guess was incorrect. In the latter event, he would repeat the procedure for other keystream blocks with the given difference. We show that the process when repeated a finite number of times, does indeed yield the value of the secret key.

In the second part of the paper, we observe that the previous attack was limited to internal state differences that occurred at time instances that were congruent to 0 mod 80. We further observe that by generalizing the attack to include internal state differences that are congruent to all equivalence classed modulo 80, we lower the total number of keystream bits required to perform the attack and in the process reduce the attack complexity to 269.98 Plantlet encryptions.
Security of Symmetric Primitives against Key-Correlated Attacks
Authors: Connolly Aisling , Farshim Pooya , Fuchsbauer Georg
Published: November 2020

We study the security of symmetric primitives against key-correlated attacks (KCA), whereby an adversary can arbitrarily correlate keys, messages, and ciphertexts. Security against KCA is required whenever a primitive should securely encrypt key-dependent data, even when it is used under related keys. KCA is a strengthening of the previously considered notions of related-key attack (RKA) and key-dependent message (KDM) security. This strengthening is strict, as we show that 2-round Even–Mansour fails to be KCA secure even though it is both RKA and KDM secure. We provide feasibility results in the ideal-cipher model for KCAs and show that 3-round Even–Mansour is KCA secure under key offsets in the random-permutation model. We also give a natural transformation that converts any authenticated encryption scheme to a KCA-secure one in the random-oracle model. Conceptually, our results allow for a unified treatment of RKA and KDM security in idealized models of computation.
Improved Meet-in-the-Middle Preimage Attacks against AES Hashing Modes
Authors: Bao Zhenzhen , Ding Lin , Guo Jian , Wang Haoyang , Zhang Wenying
Published: November 2020

Hashing modes are ways to convert a block cipher into a hash function, and those with AES as the underlying block cipher are referred to as AES hashing modes. Sasaki in 2011, introduced the first preimage attack against AES hashing modes with the AES block cipher reduced to 7 rounds, by the method of meet-in-the-middle. In his attack, the key-schedules are not taken into account. Hence, the same attack applies to all three versions of AES. In this paper, by introducing neutral bits from the key, extra degree of freedom is gained, which is utilized in two ways, i.e., to reduce the time complexity and to extend the attack to more rounds. As an immediate result, the complexities of 7-round pseudo-preimage attacks are reduced from 2120 to 2104, 296, and 296 for AES-128, AES-192, and AES-256, respectively. By carefully choosing the neutral bits from the key to cancel those from the state, the attack is extended to 8 rounds for AES-192 and AES-256 with complexities 2112 and 296. Similar results are obtained for Kiasu-BC, a tweakable block cipher based on AES-128, and interestingly the additional input tweak helps reduce the complexity and extend the attack to one more round. To the best of our knowledge, these are the first preimage attacks against 8-round AES hashing modes.
Combiners for AEAD
Authors: Poettering Bertram , Rösler Paul
Published: November 2020

The Authenticated Encryption with Associated Data (AEAD) primitive, which integrates confidentiality and integrity services under a single roof, found wide-spread adoption in industry and became indispensable in practical protocol design. Recognizing this, academic research put forward a large number of candidate constructions, many of which come with provable security guarantees. Nevertheless, the recent past has shaken up with the discovery of vulnerabilities, some of them fatal, in well-regarded schemes, stemming from weak underlying primitives, flawed security arguments, implementation-level vulnerabilities, and so on. Simply reacting to such findings by replacing broken candidates by better(?) ones is in many cases unduly, costly, and sometimes just impossible. On the other hand, as attack techniques and opportunities change over time, it seems venturous to propose any specific scheme if the intended lifetime of its application is, say, twenty years.In this work we study a workable approach towards increasing the resilience against unforeseen breaks of AEAD primitives. Precisely, we consider the ability to combine two AEAD schemes into one such that the resulting AEAD scheme is secure as long as at least one of its components is (or: as long as at most one component is broken). We propose a series of such combiners, some of which work with fully generic AEAD components while others assume specific internal structures of the latter (like an encrypt-then-MAC design). We complement our results by proving the optimality of our constructions by showing the impossibility of combiners that get along with less invocations of the component algorithms.
Swap and Rotate: Lightweight Linear Layers for SPN-based Blockciphers
Authors: Banik Subhadeep , Balli Fatih , Regazzoni Francesco , Vaudenay Serge
Published: November 2020

In CHES 2017, Jean et al. presented a paper on “Bit-Sliding” in which the authors proposed lightweight constructions for SPN based block ciphers like AES, PRESENT and SKINNY. The main idea behind these constructions was to reduce the length of the datapath to 1 bit and to reformulate the linear layer for these ciphers so that they require fewer scan flip-flops (which have built-in multiplexer functionality and so larger in area as compared to a simple flip-flop). In this paper, we develop their idea even further in few separate directions.First, we prove that given an arbitrary linear transformation, it is always possible to construct the linear layer using merely 2 scan flip-flops. This points to an optimistic venue to follow to gain further GE reductions, yet the straightforward application of the techniques in our proof to PRESENT and GIFT leads to inefficient implementations of the linear layer, as reducing ourselves to 2 scan flip-flops setting requires thousands of clock cycles and leads to very high latency.Equipped with the well-established formalism on permutation groups, we explore whether we can reduce the number of clock cycles to a practical level, i.e. few hundreds, by adding few more pairs of scan flip flops. For PRESENT, we show that 4 (resp. 8, 12) scan flip-flops are sufficient to complete the permutation layer in 384 (resp. 256, 128) clock cycles. For GIFT, we show that 4 (resp. 8, 10) scan flip flops correspond to 320 (resp. 192, 128) clock cycles. Finally, in order to provide the best of the two worlds (i.e. circuit area and latency), we push our scan flip-flop choices even further to completely eliminate the latency incurred by the permutation layer, without compromising our stringent GE budget. We show that not only 12 scan flip flops are sufficient to execute PRESENT permutation in 64 clock cycles, but also the same scan flip flops can be used readily in a combined encryption decryption circuit. Our final design of PRESENT and GIFT beat the record of Jean et al. and Banik et al. in both latency and in circuit-size metric. We believe that the techniques presented in our work can also be used at choosing bit-sliding-friendly linear layer permutations for the future SPN-based designs.
Improved Security Bounds for Generalized Feistel Networks
Authors: Shen Yaobin , Guo Chun , Wang Lei
Published: November 2020

We revisit the security of various generalized Feistel networks. Concretely, for unbalanced, alternating, type-1, type-2, and type-3 Feistel networks built from random functions, we substantially improve the coupling analyzes of Hoang and Rogaway (CRYPTO 2010). For a tweakable blockcipher-based generalized Feistelnetwork proposed by Coron et al. (TCC 2010), we present a coupling analysis and for the first time show that with enough rounds, it achieves 2n-bit security, and this provides highly secure, double-length tweakable blockciphers.
On the Composition of Single-Keyed Tweakable Even-Mansour for Achieving BBB Security
Authors: Chakraborti Avik , Nandi Mridul , Talnikar Suprita , Yasuda Kan
Published: November 2020

Observing the growing popularity of random permutation (RP)-based designs (e.g, Sponge), Bart Mennink in CRYPTO 2019 has initiated an interesting research in the direction of RP-based pseudorandom functions (PRFs). Both are claimed to achieve beyond-the-birthday-bound (BBB) security of 2n/3 bits (n being the input block size in bits) but require two instances of RPs and can handle only oneblock inputs. In this work, we extend research in this direction by providing two new BBB-secure constructions by composing the tweakable Even-Mansour appropriately. Our first construction requires only one instance of an RP and requires only one key. Our second construction extends the first to a nonce-based Message Authentication Code (MAC) using a universal hash to deal with multi-block inputs. We show that the hash key can be derived from the original key when the underlying hash is the Poly hash. We provide matching attacks for both constructions to demonstrate the tightness of the proven security bounds.
Optimizing Implementations of Linear Layers
Authors: Xiang Zejun , Zeng Xiangyoung , Lin Da , Bao Zhenzhen , Zhang Shasha
Published: November 2020

In this paper, we propose a new heuristic algorithm to search efficient implementations (in terms of Xor count) of linear layers used in symmetric-key cryptography. It is observed that the implementation cost of an invertible matrix is related to its matrix decomposition if sequential-Xor (s-Xor) metric is considered, thus reducing the implementation cost is equivalent to constructing an optimized matrix decomposition. The basic idea of this work is to find various matrix decompositions for a given matrix and optimize those decompositions to pick the best implementation. In order to optimize matrix decompositions, we present several matrix multiplication rules over F2, which are proved to be very powerful in reducing the implementation cost. We illustrate this heuristic by searching implementations of several matrices proposed recently and matrices already used in block ciphers and Hash functions, and the results show that our heuristic performs equally good or outperforms Paar’s and Boyar-Peralta’s heuristics in most cases.
Beyond-Birthday-Bound Secure Cryptographic Permutations from Ideal Ciphers with Long Keys
Authors: Nakamichi Ryota , Iwata Tetsu
Published: November 2020

Coron et al. showed a construction of a 3-round 2n-bit cryptographic permutation from three independent n-bit ideal ciphers with n-bit keys (TCC 2010). Guo and Lin showed a construction of a (2d − 1)-round dn-bit cryptographic permutation from 2d − 1 independent n-bit ideal ciphers with kn-bit keys, where d = k + 1 (Cryptography and Communications, 2015). These constructions have an indifferentiability security bound of O(q2/2n) against adversaries that make at most q queries. The bound is commonly referred to as birthday-bound security. In this paper, we show that a 5-round version of Coron et al.’s construction and (2d+1)-round version of Guo and Lin’s construction yield a cryptographic permutation with an indifferentiability security bound of O(q2/22n), i.e., by adding two more rounds, these constructions have beyond-birthday-bound security. Furthermore, under the assumption that q ≤ 2n, we show that Guo and Lin’s construction with 2d+2l−1 rounds yields a cryptographic permutation with a security bound of O(q2/2(l+1)n), where 1 ≤ l ≤ d − 1, i.e., the security bound exponentially improves by adding every two more rounds, up to 4d − 3 rounds. To the best of our knowledge, our result gives the first cryptographic permutation that is built from n-bit ideal ciphers and has a full n-bit indifferentiability security bound.
Design of Symmetric-Key Primitives for Advanced Cryptographic Protocols
Authors: Aly Abdelrahaman , Ashur Tomer , Ben-Sasson Eli , Dhooghe Siemen , Szepieniec Alan
Published: November 2020

While traditional symmetric algorithms like AES and SHA-3 are optimized for efficient hardware and software implementations, a range of emerging applications using advanced cryptographic protocols such as multi-party computation and zero knowledge proofs require optimization with respect to a different metric: arithmetic complexity.In this paper we study the design of secure cryptographic algorithms optimized to minimize this metric. We begin by identifying the differences in the design space between such arithmetization-oriented ciphers and traditional ones, with particular emphasis on the available tools, efficiency metrics, and relevant cryptanalysis. This discussion highlights a crucial point—the considerations for designing arithmetization-oriented ciphers are oftentimes different from the considerations arising in the design of software- and hardware-oriented ciphers.The natural next step is to identify sound principles to securely navigate this new terrain, and to materialize these principles into concrete designs. To this end, we present the Marvellous design strategy which provides a generic way to easily instantiate secure and efficient algorithms for this emerging domain. We then show two examples for families following this approach. These families — Vision and Rescue — are benchmarked with respect to three use cases: the ZK-STARK proof system, proof systems based on Rank-One Constraint Satisfaction (R1CS), and Multi-Party Computation (MPC). These benchmarks show that our algorithms achieve a highly compact algebraic description, and thus benefit the advanced cryptographic protocols that employ them.
Differential Attacks on CRAFT Exploiting the Involutory S-boxes and Tweak Additions
Authors: Guo Hao , Sun Siwei , Shi Danping , Sun Ling , Sun Yao , Hu Lei , Wang Meiqin
Published: November 2020

CRAFT is a lightweight tweakable block cipher proposed at FSE 2019, which allows countermeasures against Differential Fault Attacks to be integrated into the cipher at the algorithmic level with ease. CRAFT employs a lightweight and involutory S-box and linear layer, such that the encryption function can be turned into decryption at a low cost. Besides, the tweakey schedule algorithm of CRAFT is extremely simple, where four 64-bit round tweakeys are generated and repeatedly used. Due to a combination of these features which makes CRAFT exceedingly lightweight, we find that some input difference at a particular position can be preserved through any number of rounds if the input pair follows certain truncated differential trails. Interestingly, in contrast to traditional differential analysis, the validity of this invariant property is affected by the positions where the constant additions take place. We use this property to construct “weak-tweakey” truncated differential distinguishers of CRAFT in the single-key model. Subsequently, we show how the tweak additions allow us to convert these weak-tweakey distinguishers into ordinary secret-key distinguishers based on which key-recovery attacks can be performed. Moreover, we show how to construct MILP models to search for truncated differential distinguishers exploiting this invariant property. As a result, we find a 15-round truncated differential distinguisher of CRAFT and extend it to a 19-round key-recovery attack with 260.99 data, 268 memory, 294.59 time complexity, and success probability 80.66%. Also, we find a 14-round distinguisher with probability 2−43 (experimentally verified), a 16-round distinguisher with probability 2−55, and a 20-round weak-key distinguisher (2118 weak keys) with probability 2−63. Experiments on round-reduced versions of the distinguishers show that the experimental probabilities are sometimes higher than predicted. Finally, we note that our result is far from threatening the security of the full CRAFT.
Exploring Secret Keys in Searching Integral Distinguishers Based on Division Property
Authors: Wang Senpeng , Hu Bin , Guan Jie , Zhang Kai , Shi Tairong
Published: November 2020

Division property proposed by Todo at EUROCRYPT 2015 is a generalized integral property. Then, conventional bit-based division property (CBDP) and bitbased division property using three subsets (BDPT) were proposed by Todo and Morii at FSE 2016. At ASIACRYPT 2016, Xiang et al. extended Mixed Integer Linear Programming (MILP) method to search integral distinguishers based on CBDP. And at ASIACRYPT 2019, Wang et al. proposed an MILP-aided method of searching integral distinguishers based on BDPT. Although BDPT is powerful in searching integral distinguishers, the accuracy is not perfect.For block cipher SPECK32, as the block size is only 32 bits, we can experimentally observe the behaviors of all the plaintexts under a fixed key. By testing 210 random secret keys, we experimentally find a better integral distinguisher of 6-round SPECK32 with 30 active bits. But this experimental integral distinguisher cannot be proved by existing methods. So there still exists a gap between the proved distinguisher and the experimental one.To fill the gap, we explore secret keys in searching integral distinguishers based on BDPT. We put forward a situation where “Xor with The Secret Key” operation can be bypassed. Based on the new BDPT propagation rule, an improved automatic algorithm of searching integral distinguishers is proposed. For SPECK32, our improved algorithm can find the 6-round integral distinguisher with 230 chosen plaintexts. The gap between the proved distinguisher and the experimental one is filled. Moreover, we apply this improved method to search the integral distinguishers of SPECK, KATAN/KTANTAN, SIMON, SIMECK, SIMON(102), PRESENT and RECTANGLE block ciphers. The integral distinguishers found by our improved method are better than or consistent with the previous longest distinguishers.
Errata to Sound Hashing Modes of Arbitrary Functions, Permutations, and Block Ciphers
Authors: Gunsing Aldo , Daemen Joan , Mennink Bart
Published: November 2020

In ToSC 2018(4), Daemen et al. performed an in-depth investigation of sound hashing modes based on arbitrary functions, permutations, or block ciphers. However, for the case of invertible primitives, there is a glitch. In this errata, we formally fix this glitch by adding an extra term to the security bound, q/2b−n, where q is query complexity, b the width of the permutation or the block size of the block cipher, and n the size of the hash digest. For permutations that are wider than two times the chaining value this term is negligible. For block cipher based hashing modes where the block size is close to the digest size, the term degrades the security significantly.
Dasta – Alternative Linear Layer for Rasta
Authors: Hebborn Phil , Leander Gregor
Published: November 2020

Progress in the areas of multi-party computation (MPC) and fully homomorphic encryption (FHE) caused the demand of new design strategies, that minimize the number of multiplications in symmetric primitives. Rasta is an approach for a family of stream ciphers with an exceptional low AND depth, which equals the number of ANDs per encrypted bit. This is achieved in particular by randomizing parts of the computation with the help of a PRNG, implying that the security arguments rely on the provided randomness and the encryption/ decryption is potentially slowed down by this generation.In this paper we propose a variant of Rasta that achieves the same performance with respect to the AND depth and the number of ANDs per encrypted bit, but does not rely on a PRNG, i.e. is based on fixed linear layers.
WAGE: An Authenticated Encryption with a Twist
Authors: AlTawy Riham , Gong Guang , Mandal Kalikinkar , Rohit Raghvendra
Published: November 2020

This paper presents WAGE, a new lightweight sponge-based authenticated cipher whose underlying permutation is based on a 37-stage Galois NLFSR over F27. At its core, the round function of the permutation consists of the well-analyzed Welch-Gong permutation (WGP), primitive feedback polynomial, a newly designed 7-bit SB sbox and partial word-wise XORs. The construction of the permutation is carried out such that the design of individual components is highly coupled with cryptanalysis and hardware efficiency. As such, we analyze the security of WAGE against differential, linear, algebraic and meet/miss-in-the-middle attacks. For 128-bit authenticated encryption security, WAGE achieves a throughput of 535 Mbps with hardware area of 2540 GE in ASIC ST Micro 90 nm standard cell library. Additionally, WAGE is designed with a twist where its underlying permutation can be efficiently turned into a pseudorandom bit generator based on the WG transformation (WG-PRBG) whose output bits have theoretically proved randomness properties.
Saturnin: a suite of lightweight symmetric algorithms for post-quantum security
Authors: Canteaut Anne , Duval Sébastien , Leurent Gaëtan , Naya-Plasencia María , Perrin Léo , Pornin Thomas , Schrottenloher André
Published: November 2020

The cryptographic algorithms needed to ensure the security of our communications have a cost. For devices with little computing power, whose number is expected to grow significantly with the spread of the Internet of Things (IoT), this cost can be a problem. A simple answer to this problem is a compromise on the security level: through a weaker round function or a smaller number of rounds, the security level can be decreased in order to cheapen the implementation of the cipher. At the same time, quantum computers are expected to disrupt the state of the art in cryptography in the near future. For public-key cryptography, the NIST has organized a dedicated process to standardize new algorithms. The impact of quantum computing is harder to assess in the symmetric case but its study is an active research area.In this paper, we specify a new block cipher, Saturnin, and its usage in different modes to provide hashing and authenticated encryption in such a way that we can rigorously argue its security in the post-quantum setting. Its security analysis follows naturally from that of the AES, while our use of components that are easily implemented in a bitsliced fashion ensures a low cost for our primitives. Our aim is to provide a new lightweight suite of algorithms that performs well on small devices, in particular micro-controllers, while providing a high security level even in the presence of quantum computers. Saturnin is a 256-bit block cipher with a 256-bit key and an additional 9-bit parameter for domain separation. Using it, we built two authenticated ciphers and a hash function.• Saturnin-CTR-Cascade is an authenticated cipher using the counter mode and a separate MAC. It requires two passes over the data but its implementation does not require the inverse block cipher.• Saturnin-Short is an authenticated cipher intended for messages with a length strictly smaller than 128 bits which uses only one call to Saturnin to providenconfidentiality and integrity.• Saturnin-Hash is a 256-bit hash function. In this paper, we specify this suite of algorithms and argue about their security in both the classical and the post-quantum setting.

https://project.inria.fr/saturnin/
SKINNY-AEAD and SKINNY-Hash
Authors: Beierle Christof , Jean Jérémy , Kölbl Stefan , Leander Gregor , Moradi Amir , Peyrin Thomas , Sasaki Yu , Sasdrich Pascal , Sim Siang Meng
Published: November 2020

We present the family of authenticated encryption schemes SKINNY-AEAD and the family of hashing schemes SKINNY-Hash. All of the schemes employ a member of the SKINNY family of tweakable block ciphers, which was presented at CRYPTO 2016, as the underlying primitive. In particular, for authenticated encryption, we show how to instantiate members of SKINNY in the Deoxys-I-like ΘCB3 framework to fulfill the submission requirements of the NIST lightweight cryptography standardization process. For hashing, we use SKINNY to build a function with larger internal state and employ it in a sponge construction. To highlight the extensive amount of third-party analysis that SKINNY obtained since its publication, we briefly survey the existing cryptanalysis results for SKINNY-128-256 and SKINNY-128-384 as of February 2020. In the last part of the paper, we provide a variety of ASIC implementations of our schemes and propose new simple SKINNY-AEAD and SKINNY-Hash variants with a reduced number of rounds while maintaining a very comfortable security margin.

https://csrc.nist.gov/Projects/Lightweight-Cryptography
INVESTIGATION IN THE USE OF COWPEA CHAFF AS AN ADDITIVE FOR NATURAL RUBBER.
Authors: Akinlabi A. K. , Akinfenwa S. B. , Idowu T. D. , Laleye N. R. , Akinwunmi F. , Mosaku A. M , Falomo A. , Oladipo G. , Oni S. O. , Falope F. Y , Ilesanmi N. Y , Aborode T. O.
Published: November 2020

Natural rubber is a gummy liquid obtained from the sap fluid of the tree Hevea brasilensis. It is a natural hydrocarbon polymer of 2-methyl-1-3-butadiene (isoprene), which contains one double bond per repeating unit, whose structural arrangement typifies that of a cis-isomer (cis-polyisoprene). Natural rubber in its raw gum state is tacky, fairly elastic but suffers some limitations such as poor resistance to weathering condition, low tensile strength and hence additives are always added to improve on the limitations of the natural Rubber. Most additives are imported hence constituting additional cost. Cowpea chaff was used in this study as one of the additives. The cowpea chaff was chosen for this research due to its availability and cost since it is a waste material and expected to reduce cost of production. The cowpea chaff was grinded and sieved to fine particles (powder) using 100µm. The cowpea chaff powder was divided into portions and part were modified via nitration. The modified and unmodified cowpea chaff powder were characterized to determine the Ash content, Moisture content, Volatile content, pH, Loss on ignition, X-ray florescence (XRF) analysis was carried out to ascertain the elemental composition and Infra-red spectroscopy (FT-IR) to determine the functional groups and extent of the reaction of the samples. Each of the portions were compounded with Natural Rubber (NR) using calcium carbonate as control. The physico-mechanical properties of the vulcanizates obtained were determined. The study showed that chemically modified and unmodified cowpea chaff powders were good additives (softeners). Based on the parameters tested, it can be concluded that cowpea chaff can be substituted with CaCO3 filler in NR vulcanizates.
Comparative Analysis of Symptomatic and Asymptomatic SARS-CoV-2 Infection in Children
Authors: Li Jiahui , Thoon Koh Cheng , Chong Chia Yin , Maiwald Matthias , Kam Kai-qian , Nadua Karen , Tan Natalie WH , Yung Chee Fu
Published: November 2020

Introduction: In this study, a comparison of clinical, epidemiological and laboratory parameters between symptomatic and asymptomatic children with SARS-CoV-2 infection was performed. Materials and Methods: Data from all children with laboratory confirmed SARS-CoV-2 infection admitted to KK Women’s and Children’s Hospital (KKH), Singapore, from January to May 2020 were analysed. Results: Of the 39 COVID-19 children included, 38.5% were asymptomatic. Household transmission accounted for 95% of cases. The presenting symptoms of symptomatic children were low-grade fever (54.2%), rhinorrhoea (45.8%), sore throat (25%), diarrhoea (12.5%) and acute olfactory dysfunction (5.4%). Children of Chinese ethnicity (37.5% vs 6.7%), complete blood count (45.8% vs 6.7%) and liver enzyme abnormalities (25% vs 7.7%) were more common in symptomatic versus asymptomatic children. All children had a mild disease course and none required oxygen supplementation or intensive care. Conclusions: The high proportion of asymptomatic infected children coupled with household transmission as the main source of paediatric COVID-19 infection underscores the importance of early screening and isolation of children upon detection of an index case of COVID-19 in a household. Symptomatic children were more likely to have abnormal laboratory parameters but they did not have a poorer outcome compared to asymptomatic cases. Keywords: COVID-19, Paediatric, Pandemic, Singapore
Chronic Pelvic Pain and Hematuria Associated with Posterior Nutcracker Syndrome
Authors:   Department of Radiology, Oncology National Institute, Ibn Sina University Hospital, Faculty of medicine and pharmacy of Rabat, Morocco., Belkouchi Dr. L.
Published: November 2020

The nutcracker syndrome is a rare syndrome in which the left renal vein is compressed between the aorta and the superior mesenteric artery or even more rarely between the aorta and vertebral body, in case of an anatomical variation of the left renal vein. It is more likely discovered within young patients presenting pelvic pain, hematuria, or varicocele. Treatments vary from conservative, to surgical or endovascular. Here we present the case of a young patient with chronic pelvic pain and hematuria, diagnosed as a posterior nutcracker syndrome.
Prevention programs and prenatal diagnosis for beta thalassemia in Pakistan: a narrative review
Authors: Mahmood Ghafoor  , Muhammad Farooq Sabar  , Furqan Sabir
Published: November 2020

Abstract

Beta thalassemia in Pakistan is a serious health concern with an estimated 5-8% carrier frequency and birth of 5000 major children every year in the country. The treatment of beta thalassemia major patients poses a great economic burden; hence, the ideal approach towards this disease should encompass effective prevention services. At present only one government funded project “Punjab Thalassemia Prevention Program” existed in Punjab province, and providing free of cost services for beta thalassemia screening and prenatal diagnosis. Complete blood count and hemoglobin electrophoresis remains the preliminary test for screening, while chorionic villi sampling and amplification refractory mutation system method have been most widely used for molecular diagnosis of beta thalassemia. Modern molecular techniques, non-invasive prenatal diagnosis, and pre-implantation diagnosis are in trial phases. In this review we have discussed the available diagnostic facilities and status of prevention programs for beta thalassemia in Pakistan as well as future perspectives.Continuous..
Vícios intelectuais, virtudes e investigação
Authors: Santos Felipe Rocha L.
Published: November 2020

Este artigo tem como objetivo propor uma definição de virtudes e vícios intelectuais relativos a uma investigação. Por investigação aqui entende-se qualquer busca que proporcione um produto epistêmico como por exemplo Conhecimento ou Entendimento. Para isso, faço uma análise da definição de virtudes e vícios oferecida por Quassim Cassam e discuto alguns problemas desta definição. Proponho que, ao contrário de Cassam e de Duncan Pritchard, a meta de uma investigação não é apenas Conhecimento ou apenas Entendimento. Em seguida, na parte final do artigo, proponho duas aplicações práticas a definição de virtudes e vícios intelectuais. A primeira eu descrevo como o uso da Internet pode proporcionar em nós mais vícios que virtudes intelectuais, e a segunda descrevo que na prática e pesquisa médica, ao que parece, também há mais vícios que virtudes intelectuais.
O modo de conhecimento do gênio e do santo
Authors: Bassoli Selma
Published: November 2020

O gênio  e o santo são figuras de destaque na filosofia de Schopenhauer, pois a elas é atribuída a capacidade de conhecer de um modo privilegiado, adquirida através de uma modificação na forma como os seres humanos usualmente conhecem. Essa forma de conhecimento se caracteriza por sua independência em relação ao princípio de razão suficiente, que acontece quando o intelecto se liberta do domínio da vontade.  A liberdade intelectual pode proporcionar tanto a contemplação estética  para o gênio quanto o quietivo da vontade para o santo. O nosso objetivo será mostrar que o quietivo possui um aspecto que o diferencia da contemplação, visto que somente ele caracteriza a negação da vontade de viver, pois esta, ao interromper a afirmação da vontade , promove simultaneamente a destruição do corpo, o qual é considerado o foco a partir do qual a vontade se afirma.
A consciência como uma percepção do mental e o estatuto dos fenômenos mentais inconscientes na perspectiva de David Armstrong
Authors: Prata Tárik de Athayde
Published: November 2020

O artigo examina a teoria de David Armstrong sobre a consciência e sua concepção do inconsciente. Após uma discussão do caráter anti-cartesiano dessa teoria (seção 1), são discutidas as noções de consciência mínima e consciência perceptiva (seção 2), bem como o conceito de consciência introspectiva, que é o mais importante para Armstrong (seção 3). A conclusão é que, apesar do valor explicativo dos seus conceitos de consciência, Armstrong defende uma perspectiva insatisfatória a respeito do inconsciente, pois essa perspectiva não dá conta da real influência do inconsciente em nossa vida mental (seção 4).
So language. Very prescribe. Wow.
Authors: Glackin Shane Nicholas
Published: November 2020

The philosophical dispute about linguistic normativity is one battlefield in a larger war over the nature of language as an object of scientific study. For those influenced by Wittgenstein, language involves following — or failing to follow — public, prescriptive rules; for Chomsky and his followers, language is a property of individual minds and brains, and the grammatical judgements of any mature individual speaker — her competence — cannot be, in any linguistic sense, “wrong”. As I argue here, the recent “doge meme” internet fad provides surprising evidence for the prescriptivist view. Normative attitudes towards linguistic practices are a ubiquitous feature of those practices, and there is no principled basis on which to regard them as non-linguistic.
Três instituições políticas no republicanismo de Jean-Jacques Rousseau
Authors: Alves Vital Francisco Celestino
Published: November 2020

Depois de estabelecer as características do corpo político ou soberano e destacar a função excepcional do legislador no Livro segundo do Contrato social, e no livro seguinte analisada a incumbência do governo na ordem política, Rousseau, no livro quarto da obra referida, se mobiliza para demonstrar a importância fundamental de algumas instituições para a manutenção dos valores republicanos. Entre as diversas instituições apresentadas pelo filósofo genebrino que visam cumprir esses objetivos, o presente artigo se concentra no exame de três delas: o tribunato, a ditadura e a censura - instituições claramente inspiradas nas instituições romanas no período da Roma republicana. Em vista disso, indagamos: em que consiste o tribunato, a ditadura e a censura no arcabouço teórico de Rousseau? Quais são suas características? Como elas podem contribuir para a conservação da República? Partindo dessas indagações, pretende-se investigar as definições das três instituições elencadas bem como suas particularidades e a maneira como elas operam e podem contribuir para a preservação da República em longo prazo.
Heidegger e a filosofia do salto
Authors: Castelo Branco Rodrigo Amorim
Published: November 2020

O intuito deste texto é fazer uma abordagem fenomenológica a respeito da terceira juntura (Fügung) das Contribuições à filosofia (Do acontecimento apropriador). Buscamos discutir de que modo o salto (der Sprung) é uma forma de passagem do primeiro princípio do pensamento (filosofia como metafísica) ao outro princípio do pensamento (meditação filosófica acolhedora do ser (Seyn) em seu profundo velamento). O salto é irrepresentável, não é passível de ser modulado por nenhum cálculo ou representação do ente, uma vez que saltar, segundo as meditações de Heidegger, indica lançar-se em uma via totalmente outra do percurso ôntico seguido pela metafísica em toda a história ocidental. O salto é o deslocamento do ser-aí (Da-sein) da zona da entidade rumo ao acolhimento da recusa do ser. Nesse sentido, o ser-aí recepciona o fundamento na sua mais singela e profunda vigência, isto é, como o Nada do ente e como fosso abissal (Ab-grund).
A trama ficcional: para além da“mentira sagrada”
Authors: Barrenechea Miguel Angel de
Published: November 2020

A proposta deste artigo é refletir sobre a perspectiva nietzschiana do conhecimento, cujosconceitos principais, como “sujeito”, “objeto”, “coisa”, “matéria”, “átomo”, etc. são apenas construtosantropomórficos para agir no mundo. Essas noções não podem ser consideradas como“conhecimento absoluto”, “objetivo” ou “incondicionado”, são apenas ferramentas vitais,empregadas por um animal inteligente, para sobreviver às contingências da existência. Peranteessas noções há duas perspectivas possíveis: há homens que aceitam o caráter ficcional doconhecimento, entendendo-o como uma “mentira artista” e outros seres humanos que acreditampiamente nas suas ficções, tentando impô-las de qualquer forma, como se fossem uma “mentirasagrada”.
Bachelard e sua interpretação filosófica da Teoria da Relatividade
Authors: De Araújo David Velanes , Da Rocha Gabriel Kafure
Published: November 2020

A Teoria da Relatividade abalou as noções mais fundamentais da física e da filosofia consideradas como absolutas até o início do século XX. Esse contexto de reforma epistêmica fez com que filósofos e cientistas repensassem a epistemologia para buscar fundamentos mais adequados à mecânica de Einstein. Gaston Bachelard trouxe em sua filosofia científica uma importante reflexão acerca das inovações da física contemporânea ao ter como seu projeto filosófico dar às ciências os fundamentos necessários para seu melhor entendimento. O presente trabalho busca caracterizar as ideias do filósofo francês de forma sistemática e pôr em destaque um filósofo por vezes esquecido nos estudos acerca da filosofia da física.
Porvir, ação e história entre a Fenomenologia do Espírito e a Ciência da Lógica
Authors: Ereño Leonardo Mattana
Published: November 2020

O objetivo deste artigo é analisar a conexão entre temporalidade e lógica, iniciando de alguns momentos de dois dos principais trabalhos de Hegel: a Fenomenologia do Espírito e a Ciência da Lógica.Na Fenomenologia do Espírito apenas pelo cancelamento do tempo nós podemos ter acesso ao conhecimento científico. Nessa passagem, Hegel expõe a relação entre o tempo da lógica e o tempo histórico. Depois, na Ciência da Lógica, nós podemos ver como o conceito é o tempo enquanto singularidade, que realiza a mediação entre duas dimensões de temporalidade. E, finalmente, na Teleologia, nós vemos a liberdade do conceito realizada concretamente através da mediação. Nesses três momentos, Hegel explica a importância do tempo da lógica como uma metacategoria no desenvolvimento do seu projeto sistemática.
Had We Lived ... Phantasms & Nieves Penitentes: Conversation between Anne Noble and Geoffrey Batchen
Authors: Noble Anne , Batchen Geoffrey
Published: November 2020

In the conversation, two of the most prominent New Zealand authors in the field of photography talk about the body of work of Anne Noble’s Antarctica photography projects. Had we lived is a re-photographic project reflecting on the tragedies of heroic age exploration (commemorating the centenary of the deaths of Robert Falcon Scott and his men on their return from the South Pole – Terra Nova Expedition or British Antarctic Expedition to the South Pole, 1912) and on the memory of Erebus tragedy of 1975, when a tourist plane flying over Antarctica crashed into Mt Erebus, killing all 257 people on board. Anne Noble re-photographed image taken by Herbert Bowers at the South Pole – the photograph of Scott and his men taken after they arrived at the South Pole to find Amundsen had already been and gone. Phantasms and Nieves Penitentes projects hint at the triumph of Antarctica over human endeavour and as a non-explorer type herself photographer Anne Noble states: “I rather liked this perverse reversal”. Both tragic events have a notable relationship to photography – Erebus in particular, as those who died were likely looking out of the aeroplane windows taking photographs at the time of impact. This relationship is addressed throughout the conversation between the two, providing an insightful commentary on the questions of authenticity, documentary value and the capacity of photography to exist in the in-between spaces of thoughtful imagining, and rational dreaming.

Keywords: Antarctica, authenticity, documentary, photographic imaginary, re-photographing