IACR News
Here you can see all recent updates to the IACR webpage. These updates are also available:
03 August 2022
Fukang Liu, Ravi Anand, Libo Wang, Willi Meier, Takanori Isobe
ePrint ReportSabrina Kunzweiler
ePrint ReportDifferent results deduced in the development of our algorithm are also interesting beyond this application. For instance, we derive a formula for the evaluation of $(2,2)$-isogenies. Given an element in Mumford coordinates, this formula outputs the (unreduced) Mumford coordinates of its image under the $(2,2)$-isogeny. Furthermore, we study $4$-torsion points on Jacobians of hyperelliptic curves and explain how to extract square-roots of coefficients of $2$-torsion points from these points.
Jingwei Jiang, Ding Wang, Guoyin Zhang, Zhiyuan Chen
ePrint ReportIn this work, we first propose a threshold oblivious pseudorandom function (TOPRF) to harden the password so that PTA schemes can resist offline password guessing attacks. Then, we employ the threshold homomorphic aggregate signature (THAS) over lattices to construct the first quantum-resistant password-based threshold single-sign-on authentication scheme with the updatable server private key. Our scheme resolves various issues arising from user corruption and server compromise, and it is formally proved secure against the quantum adversary. Comparison results show that our scheme is superior to its counterparts.
Qian Guo, Erik Mårtensson, Paul Stankovski Wagner
ePrint ReportManuel Hauke, Lukas Lamster, Reinhard Lüftenegger, Christian Rechberger
ePrint ReportWe amalgamate those orthogonal ideas and devise a new Gröbner basis algorithm, called $\texttt{M5GB}$, that combines the concepts of both worlds. In that capacity, $\texttt{M5GB}$ merges strong signature-criteria to eliminate redundant S-pairs with concepts for fast polynomial reductions borrowed from $\texttt{M4GB}$. We provide proofs of termination and correctness and a proof-of-concept implementation in C++ by means of the Mathic library. The comparison with a state-of-the-art signature-based Gröbner basis algorithm (implemented via the same library) validates our expectations of an overall faster runtime for quadratic overdefined polynomial systems that have been used in comparisons before in the literature and are also part of cryptanalytic challenges.
Shuping Mao, Tingting Guo, Peng Wang, Lei Hu
ePrint ReportRoy Rinberg, Nilaksh Agarwal
ePrint ReportNidish Vashistha, Md Latifur Rahman, Md Saad Ul Haque, Azim Uddin, Md Sami Ul Islam Sami, Amit Mazumder Shuo, Paul Calzada, Farimah Farahmandi, Navid Asadizanjani, Fahim Rahman, Mark Tehranipoor
ePrint ReportQian Guo, Erik Mårtensson
ePrint ReportShai Halevi, Eyal Kushilevitz
ePrint ReportWe first argue that the limited functionality of RORAM still suffices for certain applications. These include various applications of sampling (or sub-sampling), and in particular the very-large-scale MPC application in the setting of~ Benhamouda et al. (TCC 2020). Clearly, RORAM can be implemented using any ORAM scheme (by the Client selecting the random $r$'s by himself), but the hope is that the limited functionality of RORAM can make it faster and easier to implement than ORAM. Indeed, our main contributions are several RORAM schemes (both of the hierarchical-type and the tree-type) of lighter complexity than that of ORAM.
Alex Davidson, Gonçalo Pestana, Sofía Celi
ePrint ReportDaniel J. Bernstein
ePrint ReportAn $n(\log n)^{O(1)}$ operation count was already known in two easier special cases: norms from power-of-2 cyclotomic fields via towers of power-of-2 cyclotomic subfields, and norms from multiquadratic fields via towers of multiquadratic subfields. This paper handles more general Abelian fields by identifying tower-compatible integral bases supporting fast multiplication; in particular, there is a synergy between tower-compatible Gauss-period integral bases and a fast-multiplication idea from Rader.
As a baseline, this paper also analyzes various standard norm-computation techniques that apply to arbitrary number fields, concluding that all of these techniques use at least $n^2(\log n)^{2+o(1)}$ bit operations in the same scenario, even with fast subroutines for continued fractions and for complex FFTs. Compared to this baseline, algorithms dedicated to smooth-degree Abelian fields find each norm $n/(\log n)^{1+o(1)}$ times faster, and finish norm computations inside $S$-unit searches $n^2/(\log n)^{1+o(1)}$ times faster.
Chenyu Wang, Ding Wang, Yihe Duan, Xiaofeng Tao
ePrint ReportFuchun Lin
ePrint ReportWe begin with the honest majority setting, where efficient constructions for general purpose MPC protocols with full security are well understood assuming secure point-to-point channels. We then focus on non-malleability with respect to tampered secure point-to-point channels. (1) We show achievability of non-malleable MPC against the bounded state tampering adversary in the joint tampering model through a naive compiler approach, exploiting a known construction of interactive non-malleable codes. The construction is currently not efficient and should be understood as showing feasibility in a rather strong tampering model. (2) We show efficient constructions of non-malleable MPC protocols against weaker variants of bounded state tampering adversary in the independent tampering model, where the protocol obtained have the same asymptotic communication complexity as best MPC protocols against honest-but-curious adversary. These are all information-theoretic results and are to be contrasted against impossibility of secure MPC when secure point-to-point channels are compromised.
Though general non-malleable MPC in no honest majority setting is beyond the scope of this work, we discuss interesting applications of honest majority non-malleable MPC in the celebrated MPC-in-the-head paradigm. Other than an abstract result concerning non-malleability, we also derive, in standard model where there is no tampering, that strong (ideal/real world) privacy against malicious adversary can be achieved in a conceptually very simple way.
Runsong Wang, Xuelian Li, Juntao Gao, Hui Li, Baocang Wang
ePrint ReportVanishree Rao
ePrint ReportParas is based on cryptographic primitives, such as, threshold encryption and robust secret sharing. It does not rely on any trusted execution environments for security, unlike some existing protocols in this direction.
University of Wollongong, Australia
Job PostingClosing date for applications:
Contact: Prof Willy Susilo
More information: https://www.seek.com.au/job/57956072
Okinawa Institute of Science and Technology Graduate University
Job Posting- Conduct research on state-of-the-art FHE schemes.
- Conduct Research on new Verifiable Computation (VC) schemes applied to FHE
- Design and implementation of new FHE and VC schemes.
Skills required for the job
- Knowledge of fully homomorphic encryption
- Deep understanding of lattice-based cryptography
- Knowledge on Verifiable Computation schemes is advisable
- Experience in C desired, C++, Rust or Go relevant as well
- Familiarity with hardware languages is a plus
- Solid engineering practices and processes, such as development and testing methodology and documentation
- Quick learner, geared towards implementation
- Eager to develop new skills and willing to take ownership of projects
Ph.D. degree in Cryptography, Applied Cryptography, Cybersecurity, Mathematics, Computer Science or Engineering
Closing date for applications:
Contact: Dr. Najwa Aaraj, naaraj@alumni.princeton.edu
Okinawa Institute of Science and Technology Graduate University
Job Posting- Conduct research on state-of-the-art secure Multi Party Computation.
- Work on MPC building blocks such as,
- Secret Sharing schemes
- FHE
- Garbled Circuits
- Design and implementation of building blocks to utilize privacy-preserving cryptographic techniques to cloud computing and machine learning applications.
Skills required for the job
- Knowledge on secure Multi Party Computation.
- Knowledge in some of the following is valuable:
- Secret Sharing schemes
- Garbled Circuits
- FHE schemes
- Zero-Knowledge proofs
- Experience in C desired, C++, Rust and Python relevant as well.
- Solid engineering practices and processes, such as development and testing methodology and documentation.
- Quick learner, geared towards implementation. Eager to develop new skills and willing to take ownership of projects.
- Knowledge on machine learning would be valuable.
Ph.D. degree in Cryptography, Applied Cryptography, Cybersecurity, Mathematics or Computer Science or Engineering
Closing date for applications:
Contact: Dr. Najwa Aaraj, naaraj@alumni.princeton.edu
Okinawa Institute of Science and Technology Graduate University
Job Posting- Work on security protocols based on post-quantum primitives such as Public Key Encryption, Key Encapsulation Mechanism, Key Exchange, and Digital Signatures schemes
- Analyze existing and propose new protocol designs, with special focus on post-quantum IPSec, VPNs, SSL, TLS, etc.
- Focus on protocols for lightweight environment
- Test and benchmark optimized and secure implementations of different protocols and study the impact on real life applications
- Investigate security properties and performance-security trade-offs
- Conduct research on new and/or state-of-the-art attacks
- Design and implementation of hybrid (post quantum – classical) solutions
- Knowledge on cryptography and cybersecurity, in particular a solid background in network security, especially protocol design and evaluation
- Excellent with C, C++, Python, (JAVA and Rust will be valuable as well)
- Hard and organized worker, quick learner, geared towards implementation. Eager to develop new skills and willing to take ownership of projects
- Ph.D. degree in Cryptography, Applied Cryptography, Cybersecurity, Mathematics or Computer Science or Engineering
Closing date for applications:
Contact: Najwa Aaraj, naaraj@alumni.Princeton.edu