IACR News
Here you can see all recent updates to the IACR webpage. These updates are also available:
15 May 2023
Xiaohai Dai, Bolin Zhang, Hai Jin, Ling Ren
To address the above issue, we propose ParBFT, which employs a parallel optimistic path. As long as the leader of the optimistic path is non-faulty, ParBFT ensures low latency without requiring an accurate estimation of the network delay. We propose two variants of ParBFT, namely ParBFT1 and ParBFT2, with a trade-off between latency and communication. ParBFT1 simultaneously launches the two paths, achieves lower latency under a faulty leader, but has a quadratic message complexity even in good situations. ParBFT2 reduces the message complexity in good situations by delaying the pessimistic path, at the cost of a higher latency under a faulty leader. Experimental results demonstrate that ParBFT outperforms Ditto or BDT. In particular, when the network condition is bad, ParBFT can reach consensus through the optimistic path, while Ditto and BDT suffer from path switching and have to make progress using the pessimistic path.
Archisman Ghosh, Jose Maria Bermudo Mera, Angshuman Karmakar, Debayan Das, Santosh Gosh, Ingrid Verbauwhede, Shreyas Sen
Barbara Gigerl, Robert Primas, Stefan Mangard
In this paper, we provide the first security analysis of masked cryptographic software spanning all three layers (SW, OS, CPU). First, we apply a formal verification approach to identify leaks within the execution of masked software that are caused by the embedded OS itself, rather than on algorithmic or microarchitecture level. After showing that these leaks are primarily caused by context switching, we propose several different strategies to harden a context switching routine against such leakage, ultimately allowing masked software from previous works to remain secure when being executed on embedded OSs. Finally, we present a case study focusing on FreeRTOS, a popular embedded OS for embedded devices, running on a RISC-V core, allowing us to evaluate the practicality and ease of integration of each strategy.
Jikang Lin, Jiahui He, Yanhong Fan, Meiqin Wang
In this paper, based on the Perfect Tree energy model, we propose a new redundant design model that improve the balances of the unrolled strand tree for the purpose of reducing energy consumption. In order to obtain the redundant design, we propose a search algorithm for returning the corresponding implementation scheme. For the existing stream ciphers, the proposed model and search method can be used to provide a low-power redundancy design scheme. To verify the effectiveness, we apply our redundant model and search method in the stream ciphers (e.g., \texttt{Trivium} and \texttt{Kreyvium}) and conducted a synthetic test. The results of the energy measurement demonstrate that the proposed model and search method can obtain lower energy consumption.
Xiao Lan, Hongjian Jin, Hui Guo, Xiao Wang
Kazuma Taka, Tatusya Ishikawa, Kosei Sakamoto, Takanori Isobe
13 May 2023
Prague, Czechia, 10 September 2023
Submission deadline: 23 June 2023
Notification: 14 July 2023
University of Waterloo; Waterloo, Canada
The Department of Combinatorics and Optimization at the University of Waterloo invites applications from qualified candidates for two 3-year postdoctoral fellowship appointments in cryptography under the supervision of Prof. David Jao, Prof. Michele Mosca, and Prof. Douglas Stebila. Expertise in cryptography is essential. The focus of the positions is on post-quantum cryptography, and is funded by an NSERC Alliance Quantum Consortia grant entitled “Accelerating the transition to quantum-resistant cryptography”.
A Ph.D. degree and evidence of excellence in research are required. Successful applicants are expected to maintain an active program of research, and participate in research activities with academic and industry partners in the grant. The annual salary is $66,000. In addition, a travel fund of $3,000 per year is provided. The positions are available immediately.
Interested individuals should apply using the MathJobs site https://www.mathjobs.org/jobs/list/22461. Applications should include a cover letter describing their interest in the position, a curriculum vitae and research statement and at least three reference letters.
Applications will be considered as they are submitted until the position is filled.
The University of Waterloo acknowledges that much of our work takes place on the traditional territory of the Neutral, Anishinaabeg and Haudenosaunee peoples. The University values the diverse and intersectional identities of its students, faculty, and staff. The University regards equity and diversity as an integral part of academic excellence and is committed to accessibility for all employees. The University of Waterloo seeks applicants who embrace our values of equity, anti-racism and inclusion. As such, we encourage applications from candidates who have been historically disadvantaged and marginalized, including applicants who identify as Indigenous peoples (e.g., First Nations, Métis, Inuit/Inuk), Black, racialized, people with disabilities, women and/or 2SLGBTQ+. All qualified candidates are encouraged to apply; however, Canadians and permanent residents will be given priority.
Closing date for applications:
Contact: Douglas Stebila (dstebila@uwaterloo.ca)
More information: https://www.mathjobs.org/jobs/list/22461
IBM T. J. Watson Research Center
Closing date for applications:
Contact: Charanjit S. Jutla
More information: https://careers.ibm.com/job/18358790/cryptography-researcher-visiting-scholar-yorktown-heights-ny/?codes=IBM_CareerWebSite
11 May 2023
Mark Zhandry
- The post-quantum equivalence of indistinguishability obfuscation and differing inputs obfuscation in the restricted setting where the outputs differ on at most a polynomial number of points. Our result handles the case where the auxiliary input may contain a quantum state; previous results could only handle classical auxiliary input.
- Bounded collusion traitor tracing from general public key encryption, where the decoder is allowed to contain a quantum state. The parameters of the scheme grow polynomially in the collusion bound.
- Collusion-resistant traitor tracing with constant-size ciphertexts from general public key encryption, again for quantum state decoders. The public key and secret keys grow polynomially in the number of users.
- Traitor tracing with embedded identities in the keys, again for quantum state decoders, under a variety of different assumptions with different parameter size trade-offs.
Traitor tracing and differing inputs obfuscation with quantum decoders / auxiliary input arises naturally when considering the post-quantum security of these primitives. We obtain our results by abstracting out a core algorithmic model, which we call the Back One Step (BOS) model. We prove a general theorem, reducing many quantum results including ours to designing classical algorithms in the BOS model. We then provide simple algorithms for the particular instances studied in this work.
Ting Chen, Zihao Li, Xiapu Luo, Xiaofeng Wang, Ting Wang, Zheyuan He, Kezhao Fang, Yufei Zhang, Hang Zhu, Hongwei Li, Yan Cheng, Xiaosong Zhang
Ward Beullens, Luca De Feo, Steven D. Galbraith, Christophe Petit
István András Seres, Péter Burcsi
Thomas Kaeding
Sebastian Faust, Carmit Hazay, David Kretzler, Benjamin Schlosser
We follow this line of work, and propose a new notion of statement-oblivious threshold witness encryption. Our new notion offers the functionality of committee-based witness encryption while additionally hiding the statement used for encryption. We present two ways to build statement-oblivious threshold witness encryption, one generic transformation based on anonymous threshold identity-based encryption (A-TIBE) and one direct construction based on bilinear maps. Due to the lack of efficient A-TIBE schemes, the former mainly constitutes a feasibility result, while the latter yields a concretely efficient scheme.
Sina Aeeneh
We first explore the problem for independent and identically distributed voters where we assume that every voter follows the same conditional probability distribution for voting for different classes, given the true classification of the data point. Next, we extend our results for the case where the voters are independent but non-identically distributed. Using the derived results, we then provide a discussion on the accuracy of the truth discovery algorithms. We show that in the best-case scenarios, truth discovery algorithms operate as an amplified MVF and thereby achieve a small error rate only when the MVF achieves a small error rate, and vice versa, achieve a large error rate when the MVF also achieves a large error rate. In the worst-case scenario, the truth discovery algorithms may achieve a higher error rate than the MVF. Finally, we confirm our theoretical results using simulations.