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Here you can see all recent updates to the IACR webpage. These updates are also available:
18 December 2021
Basque Center for Applied Mathematics - BCAM
BCAM is an research center of applied mathematics located in Bilbao. Its research is transversal, covering from core developments in mathematics to the most applied aspects. It enjoys the Severo Ochoa distinction (the highest rank distinction for research centers in Spain). The position is the framework of the creation of a new research line in (post-quantum) cryptography, which falls within the Basque strategy on Quantum computing, Quantum Cryptography and Quantum save Cryptography. The research line will be lead by Prof. Ignacio Luengo (UCM, Madrid), with the collaboration of Prof. Jintai Ding (Tsinghua University).
Applications at: http://www.bcamath.org/en/research/job/ic2021-12-postdoctoral-fellow-on-post-quantum-cryptography
Closing date for applications:
Contact: Enquiries about the position can be sent to iluengo@mat.ucm.es
More information: http://www.bcamath.org/en/research/job/ic2021-12-postdoctoral-fellow-on-post-quantum-cryptography
UConn, Computer Science and Engineering Dept.
The positions provide a great opportunity for students with interest in interdisciplinary projects that combine knowledge from various fields towards the design of secure systems and protocols. We target real-world timely problems and aim to provide secure and practical solutions backed by rigorous foundations and efficient implementations/thorough performance testing. We are also interested in conceptual projects that contribute in bridging the gap between theory and practice of Cryptography. For more information about our current and previous projects please check https://ghadaalmashaqbeh.github.io/research/.
For interested students, please send your CV to ghada@uconn.edu and provide any relevant information about the topics you want to work on and the skills/related background you have.
Closing date for applications:
Contact: Ghada Almashaqbeh
More information: https://ghadaalmashaqbeh.github.io/
University of Southern Denmark, Department of Mathematics and Computer Science; Odense, Denmark
The Section of Artificial Intelligence, Cybersecurity, and Programming Languages at the Department of Mathematics and Computer Science at the University of Southern Denmark (main campus, Odense) invites applications for tenure-track assistant professor positions in Computer Science.
Application deadline: 15 February 2022.
Link to the call: https://www.sdu.dk/da/service/ledige_stillinger/1180362?sc_lang=en
The University of Southern Denmark wishes its staff to reflect the diversity of society and thus welcomes applications from all qualified candidates regardless of personal background.
Closing date for applications:
Contact:
Please feel free to reach out to Professor Fabrizio Montesi (fmontesi@imada.sdu.dk) or Assistant Professor Ruben Niederhagen (niederhagen@imada.sdu.dk) for more information.
More information: https://www.sdu.dk/da/service/ledige_stillinger/1180362?sc_lang=en
Academia Sinica, Taipei, Taiwan
Closing date for applications:
Contact: Bo-Yin Yang (by at crypto.tw)
Kai-Min Chung (kmchung at iis.sinica.edu.tw)
Danilo Francati, Alessio Guidi, Luigi Russo, Daniele Venturi
Martijn Stam
Alonso González, Hamy Ratoanina, Robin Salen, Setareh Sharifian, Vladimir Soukharev
Panagiotis Chatzigiannis, Foteini Baldimtsi, Konstantinos Chalkias
With this problem becoming apparent from early works in the blockchain space, the concept of a light client has been proposed, where a resource-constrained client such as a browser or mobile device can participate in the system by querying and/or submitting transactions without holding the full blockchain but while still inheriting the blockchain's security guarantees. A plethora of blockchain systems with different light client frameworks and implementations have been proposed, each with different functionalities, assumptions and efficiencies. In this work we provide a systematization of such light client designs. We unify the space by providing a set of definitions on their properties in terms of provided functionality, efficiency and security, and provide future research directions based on our findings.
Aarushi Goel, Matthew Green, Mathias Hall-Andersen, Gabriel Kaptchuk
In this work, we develop a new technique for efficiently adding logarithmic-sized set membership proofs to any MPC-in-the-head based zero-knowledge protocol (Ishai et al. [STOC'07]). We integrate our technique into an open source implementation of the state-of-the-art, post quantum secure zero-knowledge protocol of Katz et al. [CCS'18]. We find that using our techniques to construct ring signatures results in signatures (based only on symmetric key primitives) that are between 5 and 10 times smaller than state-of-the-art techniques based on the same assumptions. We also show that our techniques can be used to efficiently construct post-quantum secure RingCT from only symmetric key primitives.
Mostafizar Rahman, Goutam Paul
Bulbul Ahmed, Md Kawser Bepary, Nitin Pundir, Mike Borza, Oleg Raikhman, Amit Garg, Dale Donchin, Adam Cron, Mohamed A Abdel-moneum, Farimah Farahmandi, Fahim Rahman, Mark Tehranipoor
Lindsey Knowles, Edoardo Persichetti, Tovohery Randrianarisoa, Paolo Santini
Sebastian Faust, Carmit Hazay, David Kretzler, Benjamin Schlosser
In this work, we propose the notion of financially backed covert security (FBC), which ensures that the adversary is financially punished if cheating is detected. Next, we present three transformations that turn PVC protocols into FBC protocols. Our protocols provide highly efficient judging, thereby enabling practical judge implementations via smart contracts deployed on a blockchain. In particular, the judge only needs to non-interactively validate a single protocol message while previous PVC protocols required the judge to emulate the whole protocol. Furthermore, by allowing an interactive punishment procedure, we can reduce the amount of validation to a single program instruction, e.g., a gate in a circuit. An interactive punishment, additionally, enables us to create financially backed covert secure protocols without any form of common public transcript, a property that has not been achieved by prior PVC protocols.
Somayeh Dolatnezhad Samarin, Dario Fiore, Daniele Venturi, Morteza Amini
In this work, we propose a new generic compiler to convert an SKHS scheme into an MKHS scheme. Our compiler is a generalization of Matrioska for homomorphic signatures that support programs in any model of computation. When instantiated with SKHS for circuits, we recover the Matrioska compiler of Fiore and Pagnin. As an additional contribution, we show how to instantiate our generic compiler in the Turing Machines (TM) model and argue that this instantiation allows to overcome some limitations of Matrioska: - First, the MKHS we obtain require the underlying SKHS to support TMs whose size depends only linearly in the number of users. - Second, when instantiated with an SKHS with succinctness $poly(\lambda)$ and fast enough verification time, e.g., $S \cdot \log T + n \cdot poly(\lambda)$ or $T +n \cdot poly(\lambda)$ (where $T$, $S$, and $n$ are the running time, description size, and input length of the program to verify, respectively), our compiler yields an MKHS in which the time complexity of both the prover and the verifier remains $poly(\lambda)$ even if executed on programs with inputs from $poly(\lambda)$ users.
While we leave constructing an SKHS with these efficiency properties as an open problem, we make one step towards this goal by proposing an SKHS scheme with verification time $poly(\lambda) \cdot T$ under falsifiable assumptions in the standard model.
Jan Jancar, Marcel Fourné, Daniel De Almeida Braga, Mohamed Sabt, Peter Schwabe, Gilles Barthe, Pierre-Alain Fouque, Yasemin Acar
To understand the causes of this gap, we conducted a survey with 44 developers of 27 prominent open-source cryptographic libraries. The goal of the survey was to analyze if and how the developers ensure that their code executes in constant time. Our main findings are that developers are aware of timing attacks and of their potentially dramatic consequences and yet often prioritize other issues over the perceived huge investment of time and resources currently needed to make their code resistant to timing attacks. Based on the survey, we identify several shortcomings in existing analysis tools for constant-time, and issue recommendations that can make writing constant- time libraries less difficult. Our recommendations can inform future development of analysis tools, security-aware compilers, and cryptographic libraries, not only for constant-timeness, but in the broader context of side-channel attacks, in particular for micro-architectural side-channel attacks, which are a younger topic and too recent as focus for this survey.
Wasilij Beskorovajnov, Roland Gröll, Jörn Müller-Quade, Astrid Ottenhues, Rebecca Schwerdt
Huimin Li, Nele Mentens, Stjepan Picek
Loïc Ferreira
Anselme Tueno, Jonas Janneck
Qi Da, Shanjie Xu, Chun Guo
We extend this work and consider Non-Linear Confusion-Diffusion Networks (NLCDNs), i.e., networks using non-linear permutation layers, in weaker indifferentiability settings. As the main result, we prove that 3-round NLCDNs achieve the notion of sequential indifferentiability of Mandal et al. (TCC 2012). We also exhibit an attack against 2-round NLCDNs, which shows the tightness of our positive result on 3 rounds. It implies correlation intractability of 3-round NLCDNs, a notion strongly related to known-key security of block ciphers and secure hash functions. Our results provide additional insights on understanding the complexity for known-key security, as well as using confusion-diffusion paradigm for designing cryptographic hash functions.