Ruhr-Universität Bochum (RUB): Open Journal Systems
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La mètrica bescantada: La traducció de la Comèdia de Joan F. Mira com a símptoma
Get PDFThis article analyzes the metrical aspects of Joan F. Mira’s version in «Catalan-nuanced Valencian» of Dante Alighieri’s Comedy, including the theoretical references made by the translator in the paratexts of the work, in order to assess the extent to which little metrical rigor compromises the outcome of an ambitious translation task. The extensive use by the translator of the Comedy of dialephs and syneresis in contexts unusual in the Catalan poetic tradition, as well as the fact of accentuating the decasyllables without strictly respecting the traditional rules, options which are justified by the translator taking into account the metrical features of Dante’s original, compel the reader to make an extra effort in reading the work, as other scholars have already pointed out. This allows us to discuss the extent to which notions of fidelity and literalism in the field of poetry translation should be either limited to the semantic content conveyed by the translated work or whether they also affect the versifying aspects.This article analyzes the metrical aspects of Joan F. Mira’s version in «Catalan-nuanced Valencian» of Dante Alighieri’s Comedy, including the theoretical references made by the translator in the paratexts of the work, in order to assess the extent to which little metrical rigor compromises the outcome of an ambitious translation task. The extensive use by the translator of the Comedy of dialephs and syneresis in contexts unusual in the Catalan poetic tradition, as well as the fact of accentuating the decasyllables without strictly respecting the traditional rules, options which are justified by the translator taking into account the metrical features of Dante’s original, compel the reader to make an extra effort in reading the work, as other scholars have already pointed out. This allows us to discuss the extent to which notions of fidelity and literalism in the field of poetry translation should be either limited to the semantic content conveyed by the translated work or whether they also affect the versifying aspects
History of Philosophy in Nordic Upper Secondary School Curricula: Relating the Past to the Present
Get PDFAt a time when educational policies favour skills and competencies that are assumed to be generic and transferable, the role of subject content has become an important question. In the case of upper secondary school philosophy, this is particularly evident regarding the position of the history of philosophy in the construction of the subject. Without aiming to settle this controversy, we recognise that the question of how the philosophical tradition is integrated into current constructions of the subject requires further investigation. In this article, we address this task empirically by examining the role and significance of the history of philosophy in the current philosophy curricula in the five Nordic countries. The study is carried out through a qualitative content analysis of the current curricula, and a subsequent idea analysis, in order to render visible the influences of the main philosophical and didactical traditions on the formulations of the history of philosophy as subject content. The analysis reveals great diversity in how the philosophical tradition is approached. In the final section, the different approaches are identified and discussed as didactical strategies for relating the past to the present
The Future of Hidden Christian Heritage as Hybrid: Kakure Kirishitan and the Death of the Last ‘Keeper of the Books’
No full textScholars sometimes assume that the distance between the Hidden Christian so-called Kakure Kirishitan faith and Christianity in Japan has increased to make any reconciliation between the two inconceivable, but new research using a framework of ‘hybridity’ shows that this is not the case. This article is based on interviews conducted between 2020 and 2025 on the Gotō Islands, Nagasaki Prefecture, Japan. The author focuses on a rapprochement evident today between Hidden Christian social and cultural worlds and Roman Catholic cultural life, alongside an affinity of the varied groups of Kakure Kirishitan with Buddhist and Shinto practices and cultural life. This article re-considers the future of ‘Hidden Christian heritage’ in the light of the 2018 ratification of UNESCO World Heritage sites that tends to elide the Kakure Kirishitan voice. Hidden Christians are religious groups that formed after 1613 due to the ban on Christianity in Japan and continually evolved since that time
Gröbner Basis Cryptanalysis of Ciminion and Hydra
Get PDFCiminion and Hydra are two recently introduced symmetric key Pseudo- Random Functions for Multi-Party Computation applications. For efficiency, both primitives utilize quadratic permutations at round level. Therefore, polynomial system solving-based attacks pose a serious threat to these primitives. For Ciminion, we construct a quadratic degree reverse lexicographic (DRL) Gröbner basis for the iterated polynomial model via linear transformations. With the Gröbner basis we can simplify cryptanalysis, as we no longer need to impose genericity assumptions to derive complexity estimates. For Hydra, with the help of a computer algebra program like SageMath we construct a DRL Gröbner basis for the iterated model via linear transformations and a linear change of coordinates. In the Hydra proposal it was claimed that rH = 31 rounds are sufficient to provide 128 bits of security against Gröbner basis attacks for an ideal adversary with ω = 2. However, via our Hydra Gröbner basis standard term order conversion to a lexicographic (LEX) Gröbner basis requires just 126 bits with ω = 2. Moreover, using a dedicated polynomial system solving technique up to rH = 33 rounds can be attacked below 128 bits for an ideal adversary
KyberSlash: Exploiting secret-dependent division timings in Kyber implementations
Get PDFThis paper presents KyberSlash1 and KyberSlash2 – two timing vulnerabilities in several implementations (including the official reference code) of the Kyber Post-Quantum Key Encapsulation Mechanism, recently standardized as ML-KEM. We demonstrate the exploitability of both KyberSlash1 and KyberSlash2 on two popular platforms: the Raspberry Pi 2 (Arm Cortex-A7) and the Arm Cortex-M4 microprocessor. Kyber secret keys are reliably recovered within minutes for KyberSlash2 and a few hours for KyberSlash1. We responsibly disclosed these vulnerabilities to maintainers of various libraries and they have swiftly been patched. We present two approaches for detecting and avoiding similar vulnerabilities. First, we patch the dynamic analysis tool Valgrind to allow detection of variable-time instructions operating on secret data, and apply it to more than 1000 implementations of cryptographic primitives in SUPERCOP. We report multiple findings. Second, we propose a more rigid approach to guarantee the absence of variable-time instructions in cryptographic software using formal methods
All-You-Can-Compute: Packed Secret Sharing for Combined Resilience
Get PDFUnprotected cryptographic implementations are vulnerable to implementation attacks, such as passive side-channel attacks and active fault injection attacks. Recently, countermeasures like polynomial masking and duplicated masking have been introduced to protect implementations against combined attacks that exploit leakage and faults simultaneously. While duplicated masking requires O (t · e) shares to resist an adversary capable of probing t values and faulting e values, polynomial masking requires only O (t · e) shares, which is particularly beneficial for affine computation. At CHES’24, Arnold et al. showed how to further improve the efficiency of polynomial masking in the presence of combined attacks by embedding two secrets into one polynomial sharing. This essentially reduces the complexity of previous constructions by half. The authors also observed that using techniques from packed secret sharing (Grosso et al., CHES’13) cannot easily achieve combined resilience to encode an arbitrary number of secrets in one polynomial encoding. In this work, we resolve these challenges and show that it is possible to embed an arbitrary number of secrets in one encoding and propose gadgets that are secure against combined attacks. We present two constructions that are generic and significantly improve the computational and randomness complexity of existing compilers, such as the laOla compiler presented by Berndt et al. at CRYPTO’23 and its improvement by Arnold et al. For example, for an AES evaluation that protects against t probes and e faults, we improve the randomness complexity of the state-of-the-art construction when t + e > 3, leading to an improvement of up to a factor of 2.41
A TRAP for SAT: On the Imperviousness of a Transistor-Level Programmable Fabric to Satisfiability-Based Attacks
Get PDFLocking-based intellectual property (IP) protection for integrated circuits (ICs) being manufactured at untrusted facilities has been largely defeated by the satisfiability (SAT) attack, which can retrieve the secret key needed for instantiating proprietary functionality on locked circuits. As a result, redaction-based methods have gained popularity as a more secure way of protecting hardware IP. Among these methods, transistor-level programming (TRAP) prohibits the outright use of SAT attacks due to the mismatch between the logic-level at which SAT attack operates and the switch-level at which the TRAP fabric is programmed. Herein, we discuss the challenges involved in launching SAT attacks on TRAP and we propose solutions which enable expression of TRAP in propositional logic modeling in a way that accurately reflects switch-level circuit capabilities. Results obtained using a transistor-level SAT attack tool-set that we developed and are releasing corroborate that SAT attacks can be launched against TRAP. However, the increased complexity of switch-level circuit modeling prevents the attack from realistically compromising all but the most trivial IP-protected designs
SimdMSM: SIMD-accelerated Multi-Scalar Multiplication Framework for zkSNARKs
Get PDFMulti-scalar multiplication (MSM) is the primary building block in many pairing-based zero-knowledge proof (ZKP) systems. MSM at large scales has become the main bottleneck in ZKP implementations. Inspired by existing SIMD-accelerated work, we are focused on accelerating MSM computing efficiency using SIMD instructions in a single CPU environment. First, we propose a SIMD-accelerated MSM computing architecture with no write conflicts and constant memory overheads. This architecture utilizes multithreading to achieve task-level and loop-level parallelism and employs a three-tier buffer mechanism to maximize the utilization of the SIMD engine. Instanced with AVX512-IFMA instructions, we implement six SIMD elliptic curve arithmetic engines for different point addition in three coordinate systems and two groups. Moreover, we integrate our AVX-MSM implementation into the libsnark library, naming it AVX-ZK. In more detail, point deduplication and “Three-Stage” memory optimization are proposed to address problems existing in practical applications. Based on the RELIC library, our performance results on the BLS12-381 curve show that our AVX-MSM achieves up to 27.86x speedup over the most popular Pippenger algorithm. Compared with libsnark, our AVX-ZK implementation achieves over 11.53x (up to 20.26x) speedup under standard benchmarks
POTA: A Pipelined Oblivious Transfer Acceleration Architecture for Secure Multi-Party Computation
Get PDFWith the rapid development and deployment of machine learning (ML) and big data technologies, which rely heavily on sensitive user data for training and inference, ensuring privacy and data security has become a pressing challenge. Addressing this issue requires methods that safeguard sensitive information while maintaining the correctness of computational results. Secure multi-party computation (MPC), as a representative application of cryptographic techniques, offers a technical solution to this challenge by enabling privacy-preserving computations. It has been widely applied in scenarios such as cloud-based inference and other privacy-sensitive tasks. However, MPC also introduces significant performance overhead, thus limiting its further application. Our analysis reveals that the foundational element of MPC, the oblivious transfer (OT) protocol collectively account for up to 96.64% of the execution time. It is because the OT protocols are constrained by low network band- width and weak compute engines. To address these challenges, we propose POTA, a high-performance pipelined OT hardware acceleration architecture supporting the silent OT protocol. In the POTA design, we develop efficient subsystems targeting the two most compute-intensive parts: the construction of puncturable pseudoran- dom function (PPRF), and large matrix-vector multiplications under the learning parity with noise (LPN) assumption within the silent OT protocol. In addition, to address the performance overhead caused by data transfer between POTA and the host CPU, we design a host-accelerator execution pipeline to hide the considerable transmission latency. Furthermore, we design a modular multiplication module over a finite field to generate the more complex correlations required by MPC protocols. Finally, we implement a POTA prototype on Xilinx VCU129 FPGAs. Experimental results demonstrate that under various network settings, POTA achieves significant speedups, with maximum improvements of 192.57x for basic operations and 597.57x for convolutional neural networks (CNN)
Adaptive Template Attacks on the Kyber Binomial Sampler
Get PDFTemplate attacks build a Gaussian multivariate model of the side-channel leakage signal generated by each value of a targeted intermediate variable. Combined with additional steps, such as dimensionality reduction, such models can help to infer a value with nearly 100% accuracy from just a single attack trace. We demonstrate this here by reconstructing the output of the binomial sampler of a Cortex-M4 imple- mentation of the Kyber768 post-quantum key-encapsulation mechanism. However, this performance is usually significantly diminished if the device, or even just the ad- dress space, used for profiling differs from the attacked one. Here we introduce a new technique for adapting templates generated from profiling devices in order to attack another device where we are also able to record many traces, but without knowledge of the random value held by the targeted variable. We interpret the model from the profiling devices as a Gaussian mixture and use the Expectation–Maximization (EM) algorithm to adapt its means and covariances to better match the unlabelled leakage distribution observed from the attacked setting. The Kyber binomial sampler turned out to be a particularly suitable target, for two reasons. Firstly, it generates a long sequence of values drawn from a small set, limiting the number of Gaussian components that need to be adjusted. Secondly, the length of this sequence requires particularly well-adapted templates to achieve a high key-recovery success rate from a single trace. We also introduce an extended point-of-interest selection method to improve linear discriminant analysis (LDA)