International Association for Cryptologic Research

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2014-06-04
05:36 [Pub]

The following reviews shall help the IACR members and the community to buy books in cryptology and related areas. The full list of reviews / books is available at www.iacr.org/books

If you have any questions regarding the IACR book reviewing system, or would like to volunteer a review, please contact Edoardo Persichetti (University of Warsaw, Poland) via /books at iacr.org/.

New reviews in 2014:
• R. Lidl, H. Niederreiter: Finite Fields (2nd Edition)
"This volume gives a comprehensive coverage of the theory of finite fields and its most important applications such as combinatorics and coding theory. Its simple and reader-friendly style, and the inclusion of many worked examples and exercises make it suitable not only as a reference volume for the topic, but also as a textbook for a dedicated course. I highly recommend the book to any person interested in the theory of finite fields and its applications."
Year: 2008
ISBN: 978-0-521-06567-2
Review by Edoardo Persichetti (Warsaw University, Warsaw, Poland). (Date: 2014-01-30)
• A. McAndrew: Introduction to Cryptography with Open-Source Software
"This very well written book is recommended to graduate or final year undergraduate students intended to start research work on both theoretical and experimental cryptography. Most of the cryptographic protocols are illustrated by various examples and implemented using the open-source algebra software Sage. The book provides a rigorous introduction to the mathematics used in cryptographic and covers almost all modern practical cryptosystems. Also, the book is certainly a valuable resource for practitioners looking for experimental cryptography with a computer algebra system."
Year: 2011
ISBN: 978-1-4398-2570-9
Review by Abderrahmane Nitaj (LMNO, UniversitÃ© de Caen Basse Normandie, France). (Date: 2014-02-13)
• B. Martin: Codage, Cryptologie et Applications [French]
"This French book succinctly describes the mathematical principles of cryptography and error correcting codes. Once these principles are introduced, the book presents their use in some telecommunication applications (at the state of the art in 2004). The book does not define its target audience. It is probably not enough detailed for a skilled audience, nor particularly suitable for beginners and students, since it requires mathematical background that they would have to find elsewhere."
Year: 2006
ISBN: 2-88074-569-1
Review by Eric Diehl (Technicolor, Paris, France). (Date: 2014-02-12)
• T. BaignÃ¨res, P. Junod, Y. Lu, J. Monnerat, S. Vaudenay: A Classical Introduction To Cryptography Exercise Book
"The book's main goal is to show how some mathematical notions of calculus, algebra, and computer science are used to study the security of various cryptosystems. The volume is a collection of exercises, including hints and solutions, and is suitable for advanced undergraduate and graduate students as well as students in computer science and engineering and practitioners who want to understand the mathematical techniques behind cryptography."
Year: 2006
ISBN: 978-0-387-27934-3
Review by Abdelhak Azhari (Hassan II University, Casablanca, Morocco). (Date: 2014-02-12)
• J. Buchmann, U. Vollmer: Binary Quadratic Forms
"The theory of binary quadratic forms is important in algebraic number theory. This book offers a good introduction to binary quadratic forms by following an algorithmic approach. It will be useful for students and teachers interested in binary quadratic forms and their cryptographic applications."
Year: 2007
ISBN: 978-3-540-46367-2
Review by S.V. Nagaraj (RMK Engineering College, Kavaraipettai, Tamil Nadu, India). (Date: 2014-05-19)
• J. Hoffstein, J. Pipher, J. Silverman: An Introduction to Mathematical Cryptography
"This volume provides an excellent introduction to the mathematics of cryptography. Its simple style make it accessible even to readers without a consistent mathematical background. I highly recommend this book to anyone, in particular non-specialists that are interested in the topic, and students that want to approach cryptography from a mathematical point of view. It is also very useful for instructors in the same context - I personally found it an an invaluable tool for preparing my graduate cryptography course."
Year: 2008
ISBN: 978-0-387-77993-5
Review by Edoardo Persichetti (University of Warsaw, Poland). (Date: 2014-03-27)

2014-06-02
17:33 [Event][New]

Submission: 4 September 2014
From December 3 to December 5
Location: Seoul, Korea

14:08 [Job][New]

The Computer Science Department at University College London have two openings for postdoctoral researchers in cryptography. The posts are under the supervision of Dr Jens Groth with a duration of up to 2 years and a flexible starting date. Candidates must have a PhD with a strong publication record in cryptography or theoretical computer science.

UCL is one of Europe\\\'s highest ranked universities, has a large and active Information Security group and has recently been recognized by the EPSRC and GCHQ as one of UK\\\'s Academic Centres of Excellence in Cyber Security Research. The Computer Science Department is one of the largest in the UK and is located at UCL\\\'s main campus in the centre of London.

09:17 [Pub][ePrint]

Multivariate Public Key Cryptography (MPKC) has been put forth as a possible post-quantum family of cryptographic schemes. These schemes lack provable security in the reduction theoretic sense, and so their security against yet undiscovered attacks remains uncertain. The effectiveness of differential attacks on various field-based systems has prompted the investigation of differential properties of multivariate schemes to determine the extent to which they are secure from differential adversaries. Due to its role as a basis for both encryption and signature schemes we contribute to this investigation focusing on the HFE cryptosystem. We derive the differential symmetric and invariant structure of the HFE central map and provide a collection of parameter sets which make HFE provably secure against a differential adversary.

09:17 [Pub][ePrint]

Historically, multivariate public key cryptography has been less than successful at offering encryption schemes which are both secure and efficient. At PQCRYPTO \'13 in Limoges, Tao, Diene, Tang, and Ding introduced a promising new multivariate encryption algorithm based on a fundamentally new idea: hiding the structure of a large matrix algebra over a finite field. We present an attack based on subspace differential invariants inherent to this methodology. The attack is is a structural key recovery attack which is asymptotically optimal among all known attacks (including algebraic attacks) on the original scheme and its generalizations.

09:17 [Pub][ePrint]

An extended permutation is a function f : {1,...,m} -> {1,...,n}, used to map an n-element vector a to an m-element vector b by b_i = a_{f(i)}. An oblivious extended permutation allows this mapping to be done while preserving the privacy of a, b and f in a secure multiparty computation protocol. Oblivious extended permutations have

several uses, with private function evaluation (PFE) being the theoretically most prominent one.

In this paper, we propose a new technique for oblivious evaluation of

extended permutations. Our construction is at least as efficient as the existing techniques, conceptually simpler, and has wider applicability. Our technique allows the party providing the description of f to be absent during the computation phase of the protocol. Moreover, that party does not even have to exist - we show how to compute the private representation of f from private data that may itself be computed from the inputs of parties. In other words, our oblivious extended permutations can be freely composed with other privacy-preserving operations in a multiparty computation.

09:17 [Pub][ePrint]

A ciphertext-policy attribute-based encryption protocol uses bilinear pairings to provide

control access mechanisms, where the set of user\'s attributes is specified by means of a linear secret sharing scheme. In this paper we present the design of a software cryptographic library that achieves record timings for the computation of a 126-bit security level attribute-based encryption scheme. We developed all the required auxiliary building blocks and compared the computational weight that each of them adds to the overall performance of this protocol.

In particular, our single pairing and multi-pairing implementations achieve state-of-the-art

time performance at the 126-bit security level.

09:17 [Pub][ePrint]

A function f is extractable if it is possible to algorithmically extract,\'\' from any adversarial program that outputs a value y in the image of f, a preimage of y.

When combined with hardness properties such as one-wayness or collision-resistance, extractability has proven to be a powerful tool. However, so far, extractability has not been explicitly shown. Instead, it has only been considered as a non-standard *knowledge assumption* on certain functions.

We make two headways in the study of the existence of extractable one-way functions (EOWFs). On the negative side, we show that if there exist indistinguishability obfuscators for a certain class of circuits then

there do not exist EOWFs where extraction works for any adversarial program with auxiliary-input of unbounded polynomial length.

On the positive side, for adversarial programs with bounded auxiliary-input (and unbounded polynomial running time), we give the first construction of EOWFs with an explicit extraction procedure, based on relatively standard assumptions (e.g., sub-exponential hardness of Learning with Errors). We then use these functions to construct the first 2-message zero-knowledge arguments and 3-message zero-knowledge arguments of knowledge, against the same class of adversarial verifiers, from essentially the same assumptions.

09:17 [Pub][ePrint]

In this article, we study the security of iterative hash-based MACs, such as HMAC or NMAC, with regards to universal forgery attacks. Leveraging recent advances in the analysis of functional graphs built from the iteration of HMAC or NMAC, we exhibit the very first generic universal forgery attack against hash-based MACs. In particular, our work implies that the universal forgery resistance of an n-bit output HMAC construction is not 2^n queries as long believed by the community. The techniques we introduce extend the previous functional graphs-based attacks that only took in account the cycle structure or the collision probability: we show that one can extract much more meaningful secret information by also analyzing the distance of a node from the cycle of its component in the functional graph.

09:17 [Pub][ePrint]

We are interested in secure computation protocols in settings where the number of parties is huge and their data even larger. Assuming the existence of a single-use broadcast channel (per player), we demonstrate statistically secure computation protocols for computing (multiple) arbitrary dynamic RAM programs over parties\' inputs, handling (1/3-eps) fraction static corruptions, while preserving up to polylogarithmic factors the computation and memory complexities of the RAM program. Additionally, our protocol is load balanced and has polylogarithmic communication locality.

09:17 [Pub][ePrint]

In a recent celebrated breakthrough, Garg et al. (FOCS 2013) gave the first candidate for so-called indistinguishability obfuscation (iO) thereby reviving the interest in obfuscation for a general purpose. Since then, iO has been used to advance numerous sub-areas of cryptography. While indistinguishability obfuscation is a general purpose obfuscation scheme, several obfuscators for specific functionalities have been considered. In particular, special attention has been given to the obfuscation of so-called \\emph{point functions} that return zero everywhere, except for a single point $\\alpha$. A strong variant is point obfuscation with auxiliary input (AIPO), which allows an adversary to learn some non-trivial auxiliary information about the obfuscated point $\\alpha$ (Goldwasser, Tauman-Kalai; FOCS, 2005).

Multi-bit point functions are a strengthening of point functions, where on $\\alpha$, the point function returns a string $\\beta$ instead of $1$. Multi-bit point functions with auxiliary input (MB-AIPO) have been constructed by Canetti and Bitansky (Crypto 2010) and have been used by Matsuda and Hanaoka (TCC 2014) to construct CCA-secure public-key encryption schemes and by and Bitansky and Paneth (TCC 2012) to construct three-round weak zero-knowledge protocols for NP.

In this paper we present both positive and negative results. We show that if indistinguishability obfuscation exists, then MB-AIPO does not. Towards this goal, we build on techniques by Brzuska, Farshim and Mittelbach (Crypto 2014) who use indistinguishability obfuscation as a means of attacking a large class of assumptions from the Universal Computational Extractor framework (Bellare et al; Crypto 2013). On the positive side we introduce a weak version of MB-AIPO which we deem to be outside the reach of our impossibility result. We prove that this weak version of MB-AIPO suffices to construct a public-key encryption scheme that is secure even if the adversary can learn an arbitrary leakage function of the secret key, as long as the secret key remains computationally hidden. Thereby, we strengthen a result by Canetti et al. (TCC 2010) that showed a similar connection in the symmetric-key setting.