IACR News
Here you can see all recent updates to the IACR webpage. These updates are also available:
05 January 2018
Haoyu Li, Renzhang Liu, Yanbin Pan, Tianyuan Xie
ePrint ReportUniversity of Surrey, UK
Job PostingThe post is available to start in February 2018, and runs to December 2020 (salary £30,688 to £36,613 per annum).
The goal of FutureTPM is to provide a new generation of TPM-based solutions, incorporating robust and physically secure Quantum-Resistant (QR) cryptographic primitives (formally verified), to ensure long-term security, privacy and operational assurance in the complex domain of future ICT systems and services.
The successful applicant will: (i) demonstrate experience and knowledge of applied cryptography and trusted computing technologies, (ii) exposure to theoretical cryptography (in particular to simulation-based and code-based security proofs), and interest in the application of formal methods to security and cryptography, (iii) and a solid foundation in risk assessment and vulnerability analysis for cyber-physical systems.
Closing date for applications: 5 February 2018
Contact: For informal enquiries please contact Professor Liqun Chen at liqun.chen (at) surrey.ac.uk or +44 (0)1483 6844615 or Dr Thanassis Giannetsos at a.giannetsos (at) surrey.ac.uk or +44 (0) 1483 683037
More information: https://jobs.surrey.ac.uk/vacancy.aspx?ref=001018
Daniel P. Martin, Luke Mather, Elisabeth Oswald
ePrint Report04 January 2018
Ariel Hamlin, abhi shelat, Mor Weiss, Daniel Wichs
ePrint ReportThis setting was considered by Popa et al. (NSDI '14) who developed a new cryptographic primitive called Multi-Key Searchable Encryption (MKSE), together with an instantiation and an implementation within a system called Mylar, to address this goal. Unfortunately, Grubbs et al. (CCS '16) showed that the proposed MKSE definition fails to provide basic security guarantees, and that the Mylar system is susceptible to simple attacks. Most notably, if a malicious Alice colludes with the server and shares a document with an honest Bob then the privacy of all of Bob's search queries is lost.
In this work we revisit the notion of MKSE and propose a new strengthened definition that rules out the above attacks. We then construct MKSE schemes meeting our definition. We first give a simple and efficient construction using only pseudorandom functions. This construction achieves our strong security definition at the cost of increasing the server storage overhead relative to Mylar, essentially replicating the document each time it is shared. We also show that high server storage overhead is not inherent, by giving an alternate (albeit impractical) construction that manages to avoid it using obfuscation.
Ben Smyth
ePrint ReportMurali Godi, Roopa Vishwanathan
ePrint ReportChristian Badertscher, Ueli Maurer, Björn Tackmann
ePrint ReportAs DSSs serve as a building block in numerous complex cryptographic protocols, a security definition that specifies the guarantees of a DSS under composition is needed. Canetti (FOCS 2001, CSFW 2004) as well as Backes, Pfitzmann, and Waidner (CCS 2003) have described ideal functionalities for signatures in their respective composable-security frameworks. While several variants of these functionalities exist, they all share that the verification key and signature values appear explicitly.
In this paper, we describe digital signature schemes from a different, more abstract perspective. Instead of modeling all aspects of a DSS in a monolithic ideal functionality, our approach characterizes a DSS as a construction of a functionality for authentically reading values written by a certain party from certain assumed functionalities, e.g., for transmitting verification key and signature values. This approach resolves several technical complications of previous simulation-based approaches, captures the security of signature schemes in an abstract way, and allows for modular proofs.
We show that our definition is equivalent to existential unforgeability. We then model two example applications: (1) the certification of values via a signature from a specific entity, which with public keys as values is the core functionality of public-key infrastructures, and (2) the authentication of a session between a client and a server with the help of a digitally signed assertion from an identity provider. Single-sign-on mechanisms such as SAML rely on the soundness of the latter approach.
Kaiyan Zheng, Peng Wang
ePrint Report03 January 2018
Benedikt Auerbach, Bertram Poettering
ePrint ReportThis paper proposes two new proof systems for a wide set of properties that RSA and related moduli might have. The protocols are particularly efficient: The necessary computations are simple, the communication is restricted to only one round, and the exchanged messages are short. While the first protocol is based on prior work (improving on it by reducing the number of message passes from four to two), the second protocol is novel. Both protocols require a random oracle.
Falk Schellenberg, Dennis R.E. Gnad, Amir Moradi, Mehdi B. Tahoori
ePrint ReportLuxembourg Institute of Science and Technology, Luxembourg
Job PostingBased on the profile of the applicant, the topic can be either lightweight authentication protocols for IoT devices or privacy-preserving IoT data analysis protocols. More details will be available through email inquiries.
Closing date for applications: 31 March 2018
Contact: Dr. Qiang Tang
qiang.tang (at) list.lu
Pooya Farshim, Julia Hesse, Dennis Hofheinz, Enrique Larraia
ePrint Reporta) We can prove that the multilinear decisional Diffie--Hellman (MDDH) assumption holds in our setting, assuming the used ingredients are secure (in a well-defined and standard sense). In particular, and in contrast to previous constructions, our GES does not succumb to so-called ``zeroizing'' attacks. Indeed, our scheme is currently the only GES for which no known cryptanalysis applies. b) Encodings in our GES do not carry any noise. Thus, unlike previous GES constructions, there is no upper bound on the number of operations one can perform with our encodings. Hence, our GES essentially realizes what Garg et al.~(EUROCRYPT 2013) call the ``dream version'' of a GES.
Technically, our scheme extends a previous, non-graded approximate multilinear map scheme due to Albrecht et al.~(TCC 2016-A). To introduce a graded structure, we develop a new view of encodings at different levels as polynomials of different degrees.
Thomas Agrikola, Dennis Hofheinz
ePrint Report02 January 2018
University of Tartu, Estonia
Job PostingSuccessful candidates will help to design and evaluate privacy-enhancing cryptographic techniques for blockchains and perform other research duties to help with the project, coordinate and advise partners on implementing research prototypes (the candidate may or may not participate in implementing) and ensure the smooth administration of the project including the timely delivery of research output. (Some of these duties apply only to the postdoctoral researcher.) We expect candidates to be able to develop and devote significant time to their own research agenda around the theme of the project.
The EU H2020 project PRIViLEDGE requires travel to and collaboration with colleagues throughout the European Union. Full travel and equipment budget is available to support the activities of the project.
For any inquiries or to apply for the positions, submit a full research curriculum-vitae (cv), names of two references, and a research statement (obligatory for the postdoctoral researcher) to Prof Helger Lipmaa (firstname.lastname (at) ut.ee) clearly indicating the position sought. This is crucial since we have several open positions.
The project started from January 1, 2018, and will last for three years. In the case of interest, the candidates may later seek further employment but this is not necessarily guaranteed.
Closing date for applications: 1 February 2018
Contact: Helger Lipmaa
lead research fellow (research professor)
University of Tartu
helger dot lipmaa at ut dot ee
More information: https://crypto.cs.ut.ee/index.php/Main/2018priviledge
IOHK Research
Job PostingWe offer flexible work style with a chance to work in a very dynamic team with talented people from all around the world.
Review of applications will start immediately and will continue until positions are filled
Closing date for applications: 28 February 2018
More information: https://iohk.io/careers/#op-136094-research-fellow
Ruhr-Universität Bochum
Job PostingProfile:
All candidates with a PhD degree in cryptography or data security are encouraged to apply. You should have proven your excellence in research by publications in major international cryptography conferences, for example in the IACR conferences CRYPTO, EUROCRYPT, ASIACRYPT, PKC, and TCC.
The salary will depend on your qualification and will start at approximately 50k Euro (gross/year). There will be sufficient funding for attending conferences and workshops. Funding is available until October 2019, with possible extensions. Excellent group atmosphere.
Application material:
Letter of motivation, CV (incl. list of publications).
Feel free to contact me (Eike Kiltz) for any further question.
Closing date for applications: 4 February 2018
Contact: Eike Kiltz
More information: http://www.crypto.rub.de/resgroups/foc/index.html.en