Ruhr-Universität Bochum (RUB): Open Journal Systems
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HADES: Automated Hardware Design Exploration for Cryptographic Primitives
No full textWhile formal constructions for cryptographic schemes have steadily evolved and emerged over the past decades, the design and implementation of efficient and secure hardware instances are still mostly manual, tedious, and intuition-driven processes. With the increasing complexity of modern cryptography, e.g., Post-Quantum Cryptography (PQC) schemes, and consideration of physical implementation attacks, e.g., Side-Channel Analysis (SCA), the design space often grows exorbitantly without developers being able to weigh all design options.This emphasizes the evident necessity for tool-assisted Design Space Exploration (DSE) for efficient and secure cryptographic hardware. To address this demand, we present the HADES framework. This tool systematically traverses the design space driven by security requirements, rapidly predicts user-defined performance metrics, e.g., area footprint or cycle-accurate latency, and instantiates the most suitable candidate in a synthesizable Hardware Description Language (HDL).We demonstrate the capabilities of our framework by applying our proof-of-concept implementation to a wide-ranging selection of symmetric and PQC schemes, including the ChaCha20 stream cipher and the PQC standard Kyber. Notably, for these schemes, we present the first hardware implementations featuring arbitrary-order masking
Quantum security analysis of Module-LWE PQC based on practical cost estimates
No full textThe security of lattice-based cryptography relies on the computational complexity of solving the Shortest Vector Problem (SVP) on a high-dimensional lattice. Due to its efficacy in addressing SVP, lattice-based cryptographic systems have so far used the sieve algorithm to analyze their security. Previous works have analyzed the theoretical complexity improvement of the sieve algorithm in quantum computing environments, noting that Grover’s algorithm provides a quadratic speed-up for search problems. However, these works have solely focused on the theoretical analysis of query complexity, neglecting to present quantum circuit designs for sieves. Quantum circuit design and quantum resource estimation are necessary for practical analysis of the complexity of quantum sieves. Additionally, the cost of quantum error correction must also be considered, as quantum computation has a large number of errors. In this paper, we present quantum circuit designs for the sieve algorithm and provide estimates of the quantum resources required, including the number of gates and their depth. Furthermore, we evaluate the quantum sieve’s impact on the security level of ML-KEM and ML-DSA, comparing it to the classical sieve algorithm. We do this by evaluating the classical processing cost for quantum error correction using these estimates. Our results show that the quantum sieve algorithm does not break ML-KEM and ML-DSA, but it reduces their security level by 15 to 27 bits compared to the classical sieve
mid-pSquare: Leveraging the Strong Side-Channel Security of Prime-Field Masking in Software
No full textEfficiently protecting embedded software implementations of standard symmetric cryptographic primitives against side-channel attacks has been shown to be a considerable challenge in practice. This is, in part, due to the most natural countermeasure for such ciphers, namely Boolean masking, not amplifying security well in the absence of sufficient physical noise in the measurements. So-called primefield masking has been demonstrated to provide improved theoretical guarantees in this context, and the Feistel for Prime Masking (FPM) family of Tweakable Block Ciphers (TBCs) has been recently introduced by Grassi et al. (Eurocrypt’24) to efficiently leverage these advantages. However, it was so far only instantiated for and empirically evaluated in a hardware implementation context, by using a small (7-bit) prime modulus.In this paper, we build on the theoretical incentive to increase the prime field size to obtain improved side-channel (Faust et al., Eurocrypt’24) and fault (Moos et al., CHES’24) resistance, as well as on the practical incentive to instantiate an FPM instance with optimized performance on 32-bit software platforms. We introduce mid-pSquare for this purpose, a lightweight TBC operating over a 31-bit Mersenne prime field. We first provide an in-depth black-box security analysis with a particular focus on algebraic attacks – which, contrary to the cryptanalysis of instances over smaller primes, are more powerful than statistical ones in our setting. We also design a strong tweak schedule to account for potential related-tweak algebraic attacks which, so far, are almost unknown in the literature. We then demonstrate that mid-pSquare implementations deliver very competitive performance results on the target platform compared to analogous binary TBCs regardless of masked or unmasked implementation (we use fix-sliced SKINNY for our comparisons). Finally, we experimentally establish the side-channel security improvements that masked mid-pSquare can lead to, reaching unmatched resistance to profiled horizontal attacks on lightweight 32-bit processors (ARM Cortex-M4)
Neurophenomenal structuralism as a general theory of consciousness?
No full textWhile neurophenomenal structuralism (NPS) is typically viewed as an account of why an experience, i.e. a conscious mental state, has a specific phenomenal character, Sascha Fink has suggested that NPS might also account for why one has an experience in the first place. According to Fink, the character-determining structures are incorporated in larger (meta-)structures that make the incorporated structures conscious, while also contributing their own Gestalt-related phenomenology. We examine the commitments of such generalized ‘NPS+’, formulating three challenges for Fink’s approach. According to the unconsciously perceived gist objection, there is evidence for unconscious Gestalten, which suggests that the Gestalt-forming mechanism fails to make the relevant mental state conscious. Moreover, the existence of Ganzfeld experiences suggests that some experiences lack Gestalt-structures. Thirdly, as we explain, proponents of one-factor NPS+ face the mirroring dilemma of having to choose between a vicious regress of incorporating structures, and compromising their theory’s methodological promise. We then formulate two challenges for any two-factor form of NPS+: The more of the same challenge concerns the question of why adding more structures to content-related structural features makes these features conscious, while the structure-selection challenge concerns the question of why some neural structures, but not others, are selected for consciousness
Algunes consideracions sobre la traducció de textos alemanys no actuals: el cabal onomàstic alemany medieval i el seu tractament
Get PDFThe aim of this contribution is to propose guidelines by which Catalan forms can be created of the German medieval onomastic corpus, with a further task being that of proposing guidelines for the Catalanization of the German medieval culturemes, that is, for unified forms for medieval concepts of the German material, social and political culture, in order to avoid substitutive or approximate translations of these concepts. The final aim is the creation of a Catalan onomastic corpus containing the proposals for Catalan forms of the onomastic and cultural material of the German medieval
Das Bad, de Yoko Tawada: la traducció d\u27una identitat nòmada
No full textThis article analyses the translation into English, German and Spanish of Tawada’s Das Bad (1989), originally written in Japanese, but first published in German. For this purpose, a number of extracts are selected, characterised by the translation problems they pose. These are classified into three categories: metalinguistic translation problems in a single language, problems caused by the contact between Japanese and German in the original text, and problems arising from the Japanese protagonist’s learning of German. For the analysis of these fragments, a study of Tawada’s ideary is made, in which concepts such as identity, physical appearance and skin, and death stand out. The result is a reflection on the topics of Yoko Tawada’s story and on the solutions that the various translations have proposed. The conclusions are that the author’s abstract and complex ideary and reflections, together with the fact that there are two languages in contact in the original text, are factors that lead to a number of linguistic translation problems that are specific to this text.This article analyses the translation into English, German and Spanish of Tawada’s Das Bad (1989), originally written in Japanese, but first published in German. For this purpose, a number of extracts are selected, characterised by the translation problems they pose. These are classified into three categories: metalinguistic translation problems in a single language, problems caused by the contact between Japanese and German in the original text, and problems arising from the Japanese protagonist’s learning of German. For the analysis of these fragments, a study of Tawada’s ideary is made, in which concepts such as identity, physical appearance and skin, and death stand out. The result is a reflection on the topics of Yoko Tawada’s story and on the solutions that the various translations have proposed. The conclusions are that the author’s abstract and complex ideary and reflections, together with the fact that there are two languages in contact in the original text, are factors that lead to a number of linguistic translation problems that are specific to this text
Bridges for dialogue – a multifaceted learning project
Get PDFDer Artikel stellt ein handlungs- und projektorientiertes Lernvorhaben vor, in dem sich der Unterrichtsraum für Spanisch als Fremdsprache ab Niveau B2+ in einen dynamischen Raum verwandelt, der Interdisziplinarität, Transversalität und Interkulturalität integriert. Die behandelten Themen besitzen eine hohe gesellschaftliche und ökologische Relevanz sowohl für den globalen Norden als auch für den globalen Süden, was sich in der Vielfalt der Gastvortragenden widerspiegelt. Ziel ist die aktive Teilnahme an zwei authentischen Fachvorträgen (auf Deutsch und Spanisch), auf die sich die Studierenden im Rahmen individueller und kooperativer Arbeit vorbereiten, um das Lernen in allgemeinen und fachspezifischen Kursen durch projektorientiertes Arbeiten zu fördern. The article presents an action- and project-oriented learning initiative in which the classroom for Spanish as a foreign language, starting at level B2+, is transformed into a dynamic space that integrates interdisciplinarity, transversality, and interculturality. The topics addressed have high social and environmental relevance for both the Global North and the Global South, a fact reflected in the diversity of the guest speakers. The aim is the active participation in two authentic specialist lectures (in German and Spanish), for which students prepare through individual and collaborative work, in order to foster learning in both general and specific courses through project-based work
Prehistoric Copper Mining Between Hohe Salve and Hahnenkamm: First Results of Mining Archaeological Surveys in the Brixental and the Grattenbergl/Kirchbichl (North Tyrol, Austria)
No full textThe Brixental was an important connecting area between the Bronze and Iron Age copper mining districts of Schwaz-Brixlegg in the west and Kitzbühel-Jochberg in the east. For this reason, the mining landscape of the Brixental, which has been little researched to date, was investigated for potential prehistoric copper mines. Through literature research and the study of geodata (DEM, orthophotos) prior to the surveys carried out in 2023, a total of six core areas were defined, which were investigated for the presence of mining archaeological features and finds. During the survey, all relevant features like mining heaps (Bergbauhalden), depressions formed by open-cast mines or collapsed adits/”mining pits” (Pingen) and underground mines (untertägige Abbaue) were documented and samples were collected for radiocarbon dating. In this way, it was possible to provide evidence of prehistoric mining at three sites based on the artefacts discovered (stone tools, pottery, slag, etc.), while in the case of Götschen near Brixen im Thale it was possible to obtain radiocarbon dating for Early to Middle Bronze Age mining. In addition, various samples provided evidence of widespread mining activities in the Late Middle Ages and Early Modern Age. In these periods the Brunnalm in Kirchberg in Tirol was particularly important. Located at the western entrance to the Brixental, Grattenbergl in Kirchbichl was investigated using geophysical methods (geomagnetic measurements), revealing evidence of metallurgical activities (smelting furnace and/or roasting bed) during the allstatt period. It can therefore be concluded that copper mining was carried out in the Brixental that was similar to the well-known mining areas (Kitzbühel-Jochberg, Schwaz-Brixlegg) in the vicinity and that traces of it have been preserved to the present day
Zeroed Out: Cryptanalysis of Weak PRFs in Alternating Moduli
Get PDFThe growing adoption of secure multi-party computation (MPC) has driven the development of efficient symmetric key primitives tailored for MPC. Recent advances, such as the alternating moduli paradigm, have shown promise but leave room for cryptographic and practical improvements. In this paper, we analyze a family of weak pseudorandom functions (wPRF) proposed at Crypto 2024, focusing on their One-to-One parameter sets. We demonstrate that these configurations fail to achieve their intended one-to-one mappings and exploit this observation to develop an efficient key recovery attack.Our analysis reveals critical vulnerabilities, reducing the complexity of key recovery to O(2λ/2 log2 λ) for the Standard One-to-One wPRF and O(20.84λ) for the Reversed Moduli variant – both substantially below their claimed λ-bit security. We validate our findings through experimental evaluation, confirming alignment between predicted and observed attack complexities