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Vector Boolean Functions: Applications in Symmetric Cryptography
Vector Boolean Functions: Applications in Symmetric Cryptography José Antonio Álvarez Cubero Departamento de Matemática Aplicada a las Tecnologías de la Información y las Comunicaciones Universidad Politécnica de Madrid This dissertation is submitted for the degree of Doctor Ingeniero de Telecomunicación Escuela Técnica Superior de Ingenieros de Telecomunicación November 2015 I would like to thank my wife, Isabel, for her love, kindness and support she has shown during the past years it has taken me to finalize this thesis. Furthermore I would also liketo thank my parents for their endless love and support. Last but not least, I would like to thank my loved ones such as my daughter and sisters who have supported me throughout entire process, both by keeping me harmonious and helping me putting pieces together. I will be grateful forever for your love. Declaration The following papers have been published or accepted for publication, and contain material based on the content of this thesis. 1. [7] Álvarez-Cubero, J. A. and Zufiria, P. J. (expected 2016). Algorithm xxx: VBF: A library of C++ classes for vector Boolean functions in cryptography. ACM Transactions on Mathematical Software. (In Press: http://toms.acm.org/Upcoming.html) 2. [6] Álvarez-Cubero, J. A. and Zufiria, P. J. (2012). Cryptographic Criteria on Vector Boolean Functions, chapter 3, pages 51–70. Cryptography and Security in Computing, Jaydip Sen (Ed.), http://www.intechopen.com/books/cryptography-and-security-in-computing/ cryptographic-criteria-on-vector-boolean-functions. (Published) 3. [5] Álvarez-Cubero, J. A. and Zufiria, P. J. (2010). A C++ class for analysing vector Boolean functions from a cryptographic perspective. -
Integral Cryptanalysis on Full MISTY1⋆
Integral Cryptanalysis on Full MISTY1? Yosuke Todo NTT Secure Platform Laboratories, Tokyo, Japan [email protected] Abstract. MISTY1 is a block cipher designed by Matsui in 1997. It was well evaluated and standardized by projects, such as CRYPTREC, ISO/IEC, and NESSIE. In this paper, we propose a key recovery attack on the full MISTY1, i.e., we show that 8-round MISTY1 with 5 FL layers does not have 128-bit security. Many attacks against MISTY1 have been proposed, but there is no attack against the full MISTY1. Therefore, our attack is the first cryptanalysis against the full MISTY1. We construct a new integral characteristic by using the propagation characteristic of the division property, which was proposed in 2015. We first improve the division property by optimizing a public S-box and then construct a 6-round integral characteristic on MISTY1. Finally, we recover the secret key of the full MISTY1 with 263:58 chosen plaintexts and 2121 time complexity. Moreover, if we can use 263:994 chosen plaintexts, the time complexity for our attack is reduced to 2107:9. Note that our cryptanalysis is a theoretical attack. Therefore, the practical use of MISTY1 will not be affected by our attack. Keywords: MISTY1, Integral attack, Division property 1 Introduction MISTY [Mat97] is a block cipher designed by Matsui in 1997 and is based on the theory of provable security [Nyb94,NK95] against differential attack [BS90] and linear attack [Mat93]. MISTY has a recursive structure, and the component function has a unique structure, the so-called MISTY structure [Mat96]. -
Cryptography for Efficiency: New Directions In
Abstract of \Cryptography for Efficiency: New Directions in Authenticated Data Structures" by Charalampos Papamanthou, Ph.D., Brown University, May 2011. Cloud computing has emerged as an important new computational and storage medium and is increasingly being adopted both by companies and individuals as a means of reducing operational and maintenance costs. However, remotely-stored sensitive data may be lost or modified and third-party computations may not be performed correctly due to errors, op- portunistic behavior, or malicious attacks. Thus, while the cloud is an attractive alternative to local trusted computational resources, users need integrity guarantees in order to fully adopt this new paradigm. Specifically, they need to be assured that uploaded data has not been altered and outsourced computations have been performed correctly. Tackling the above problems requires the design of protocols that, on the one hand, are provably secure and at the same time remain highly efficient, otherwise the main purpose of adopting cloud computing, namely efficiency and scalability, is defeated. It is therefore essential that expertise in cryptography and efficient algorithmics be combined to achieve these goals. This thesis studies techniques allowing the efficient verification of data integrity and computations correctness in such adversarial environments. Towards this end, several new authenticated data structures for fundamental algorithmics and computation problems, e.g., hash table queries and set operations, are proposed. The main novelty of this work lies in employing advanced cryptography such as lattices and bilinear maps, towards achieving high efficiency, departing from traditional hash-based primitives. As such, the proposed techniques lead to efficient solutions that introduce minimal asymptotic overhead and at the same time enable highly-desirable features such as optimal verification mechanisms and par- allel authenticated data structures algorithms. -
Draft NISTIR 8214, Threshold Schemes for Cryptographic Primitives
1 Draft NISTIR 8214 2 Threshold Schemes for 3 Cryptographic Primitives 4 Challenges and Opportunities in Standardization and 5 Validation of Threshold Cryptography 6 Luís T. A. N. Brandão 7 Nicky Mouha 8 Apostol Vassilev 9 10 Draft NISTIR 8214 11 Threshold Schemes for 12 Cryptographic Primitives 13 Challenges and Opportunities in Standardization and 14 Validation of Threshold Cryptography 15 Luís T. A. N. Brandão 16 Nicky Mouha 17 Apostol Vassilev 18 Computer Security Division 19 Information Technology Laboratory 20 July 2018 21 22 U.S. Department of Commerce 23 Wilbur L. Ross, Jr., Secretary 24 National Institute of Standards and Technology 25 Walter Copan, NIST Director and Under Secretary of Commerce for Standards and Technology 26 National Institute of Standards and Technology Internal Report 8214 27 55 pages (July 2018) Certain commercial entities, equipment, or materials may be identified in this document in order to describe an experimental procedure or concept adequately. Such identification is not intended to imply recommendation or endorsement by NIST, nor is it intended to imply that the entities, materials, or equipment are necessarily the best available for the purpose. There may be references in this publication to other publications currently under development by NIST in accordance with its assigned statutory responsibilities. The information in this publication, including concepts and methodologies, may be used by federal agencies even before the completion of such companion publications. Thus, until each publication is completed, current requirements, guidelines, and procedures, where they exist, remain operative. For planning and transition purposes, federal agencies may wish to closely follow the development of these new publications by NIST. -
SAEB: a Lightweight Blockcipher-Based AEAD Mode of Operation
SAEB: A Lightweight Blockcipher-Based AEAD Mode of Operation Yusuke Naito1, Mitsuru Matsui1, Takeshi Sugawara2 and Daisuke Suzuki1 1 Mitsubishi Electric Corporation, Japan {Naito.Yusuke@ce,Matsui.Mitsuru@ab,Suzuki.Daisuke@bx}.MitsubishiElectric.co.jp 2 The University of Electro-Communications, Japan [email protected] Abstract. Lightweight cryptography in computationally constrained devices is ac- tively studied. In contrast to advances of lightweight blockcipher in the last decade, lightweight mode of operation is seemingly not so mature, yet it has large impact in performance. Therefore, there is a great demand for lightweight mode of oper- ation, especially that for authenticated encryption with associated data (AEAD). Among many known properties of conventional modes of operation, the following four properties are essential for constrained devices: 1. Minimum State Size: the state size equals to a block size of a blockcipher. 2. Inverse Free: no need for a blockcipher decryption. 3. XOR Only: only XOR is needed in addition to a blockcipher encryption. 4. Online: a data block is processed only once. The properties 1 and 4 contribute to small memory usage, and the properties 2 and 3 contribute to small program/circuit footprint. On top of the above properties, the fifth property regarding associated data (AD) is also important for performance: 5. Efficient Handling of Static AD: static AD can be precomputed. We design a lightweight blockcipher-based AEAD mode of operation called SAEB: the first mode of operation that satisfies all the five properties to the best of our knowledge. Performance of SAEB is evaluated in various software and hardware platforms. -
Authenticating Computation on Groups: New Homomorphic Primitives and Applications
Universita` degli Studi di Catania Dipartimento di Matematica ed Informatica Dottorato di Ricerca in Matematica Pura ed Applicata XXVI ciclo Orazio Puglisi Authenticating Computation on Groups: New Homomorphic Primitives and Applications Advisor: Ch.mo Prof. Dario Catalano ANNO ACCADEMICO 2013-2014 Contents Contents i Acknowledgments iv 1 Introduction 1 1.1 Afewwordsaboutcryptographyhistory . 1 1.2 From Encryption to Homomorphic Encryption . 3 1.3 Whatabouthomomorphicsignatures? . 4 1.4 Fromaconcreteproblemtoanewprimitive . 6 1.5 Organizationofthisthesis . 8 2 Preliminaries and notations 10 2.1 BasicNotations .......................... 10 2.1.1 Probabilisticnotation. 10 2.1.2 NumberTheory...................... 11 2.1.3 Pairings .......................... 11 2.1.4 Computationalassumptions . 12 2.2 PrimitivesandSecurity. 13 2.2.1 Usersandprimitives . 13 2.2.2 Indistinguishability under CPA and CCA . 15 2.2.3 Theasymptoticapproach . 16 2.2.4 Primitives ......................... 17 2.2.4.1 HashFunction . 17 2.2.4.2 ChameleonHashFunction . 18 2.2.4.3 PublicKeyEncryption. 19 i CONTENTS ii 2.2.4.3.1 Security for Public Key Encryption Schemes. ............... 20 2.2.4.3.2 Paillier Encryption Scheme . 22 2.2.4.4 Signatures. 23 2.2.4.4.1 Security for Digital Signatures Schemes 24 2.2.4.4.2 WatersSignature . 26 2.2.4.5 AuthenticatedEncryption . 27 2.2.4.6 SigmaProtocol . 28 2.2.4.6.1 SchnorrSigmaProtocol . 30 2.2.5 Homomorphicprimitives . 30 3 A linearly homomorphic signature scheme to sign elements in bilinear groups 32 3.1 Linear Network Coding and Linearly Homomorphic Signatures 33 3.2 HomomorphicSignaturesscheme . 34 3.2.1 Correctness and Security for Homomorphic Signatures 35 3.3 LHSG:Definition ........................ -
Towards the Generation of a Dynamic Key-Dependent S-Box to Enhance Security
Towards the Generation of a Dynamic Key-Dependent S-Box to Enhance Security 1 Grasha Jacob, 2 Dr. A. Murugan, 3Irine Viola 1Research and Development Centre, Bharathiar University, Coimbatore – 641046, India, [email protected] [Assoc. Prof., Dept. of Computer Science, Rani Anna Govt College for Women, Tirunelveli] 2 Assoc. Prof., Dept. of Computer Science, Dr. Ambedkar Govt Arts College, Chennai, India 3Assoc. Prof., Dept. of Computer Science, Womens Christian College, Nagercoil, India E-mail: [email protected] ABSTRACT Secure transmission of message was the concern of early men. Several techniques have been developed ever since to assure that the message is understandable only by the sender and the receiver while it would be meaningless to others. In this century, cryptography has gained much significance. This paper proposes a scheme to generate a Dynamic Key-dependent S-Box for the SubBytes Transformation used in Cryptographic Techniques. Keywords: Hamming weight, Hamming Distance, confidentiality, Dynamic Key dependent S-Box 1. INTRODUCTION Today communication networks transfer enormous volume of data. Information related to healthcare, defense and business transactions are either confidential or private and warranting security has become more and more challenging as many communication channels are arbitrated by attackers. Cryptographic techniques allow the sender and receiver to communicate secretly by transforming a plain message into meaningless form and then retransforming that back to its original form. Confidentiality is the foremost objective of cryptography. Even though cryptographic systems warrant security to sensitive information, various methods evolve every now and then like mushroom to crack and crash the cryptographic systems. NSA-approved Data Encryption Standard published in 1977 gained quick worldwide adoption. -
Secure E-Voting System by Utilizing Homomorphic Properties of the Encryption Algorithm
View metadata, citation and similar papers at core.ac.uk brought to you by CORE provided by TELKOMNIKA (Telecommunication Computing Electronics and Control) TELKOMNIKA, Vol.16, No.2, April 2018, pp. 862~867 ISSN: 1693-6930, accredited A by DIKTI, Decree No: 58/DIKTI/Kep/2013 DOI: 10.12928/TELKOMNIKA.v16i2.8420 862 Secure E-voting System by Utilizing Homomorphic Properties of the Encryption Algorithm Rifki Suwandi*, Surya Michrandi Nasution, Fairuz Azmi Electrical Engineering Faculty, Telkom University, Bandung, Indonesia *Corresponding author, e-mail: [email protected], [email protected], [email protected] Abstract The use of cryptography in the e-voting system to secure data is a must to ensure the authenticity of the data. In contrast to common encryption algorithms, homomorphic encryption algorithms had unique properties that can perform mathematical operations against ciphertext. This paper proposed the use of the Paillier and Okamoto-Uchiyama algorithms as two homomorphic encryption algorithms that have the additional properties so that it can calculate the results of voting data that has been encrypted without having to be decrypted first. The main purpose is to avoid manipulation and data falsification during vote tallying process by comparing the advantages and disadvantages of each algorithm. Keywords: cryptography, encryption, homomorphic, Paillier, Okamoto-Uchiyama Copyright © 2018 Universitas Ahmad Dahlan. All rights reserved. 1. Introduction There are numerous issues with the electronic vote casting system, together with system errors, network safety, information security, and so on. One of the primary issues is cheating committed by either insider or outsider, especially for some important role holders with authority that can access the system itself. -
Cryptographic Sponge Functions
Cryptographic sponge functions Guido B1 Joan D1 Michaël P2 Gilles V A1 http://sponge.noekeon.org/ Version 0.1 1STMicroelectronics January 14, 2011 2NXP Semiconductors Cryptographic sponge functions 2 / 93 Contents 1 Introduction 7 1.1 Roots .......................................... 7 1.2 The sponge construction ............................... 8 1.3 Sponge as a reference of security claims ...................... 8 1.4 Sponge as a design tool ................................ 9 1.5 Sponge as a versatile cryptographic primitive ................... 9 1.6 Structure of this document .............................. 10 2 Definitions 11 2.1 Conventions and notation .............................. 11 2.1.1 Bitstrings .................................... 11 2.1.2 Padding rules ................................. 11 2.1.3 Random oracles, transformations and permutations ........... 12 2.2 The sponge construction ............................... 12 2.3 The duplex construction ............................... 13 2.4 Auxiliary functions .................................. 15 2.4.1 The absorbing function and path ...................... 15 2.4.2 The squeezing function ........................... 16 2.5 Primary aacks on a sponge function ........................ 16 3 Sponge applications 19 3.1 Basic techniques .................................... 19 3.1.1 Domain separation .............................. 19 3.1.2 Keying ..................................... 20 3.1.3 State precomputation ............................ 20 3.2 Modes of use of sponge functions ......................... -
Securing Threshold Cryptosystems Against Chosen Ciphertext Attack∗
Securing Threshold Cryptosystems against Chosen Ciphertext Attack∗ Victor Shoupy Rosario Gennaroz September 18, 2001 Abstract For the most compelling applications of threshold cryptosystems, security against chosen ciphertext attack is a requirement. However, prior to the results presented here, there appeared to be no practical threshold cryptosystems in the literature that were provably chosen-ciphertext secure, even in the idealized random oracle model. The contribution of this paper is to present two very practical threshold cryptosystems, and to prove that they are secure against chosen ciphertext attack in the random oracle model. Not only are these protocols computationally very efficient, but they are also non-interactive, which means they can be easily run over an asynchronous communication network. 1 Introduction In a threshold cryptosystem, the secret key of a public key cryptosystem is shared among a set of decryption servers, so that a quorum of servers can act together to decrypt a given ciphertext. Just as for ordinary, non-threshold cryptosystems, a natural and very useful notion of security is that of security against chosen ciphertext attack. In this paper, we consider the problem of designing threshold cryptosystems that are secure against chosen ciphertext attack. Our goal is to design a practical scheme, and provide strong evidence that it cannot be broken. Even though the most compelling applications of threshold cryptosystems seem to require chosen-ciphertext security, prior to the results presented here, there appeared to be no practi- cal threshold cryptosystems in the literature that were provably secure | even in the random oracle model, where one models a cryptographic hash function as a random oracle. -
Speke Cycle Route
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Short Group Signatures
An extended abstract of this paper is to appear in Advances in Cryptology—CRYPTO 2004, Springer-Verlag. Short Group Signatures Dan Boneh∗ Xavier Boyen Hovav Shacham [email protected] [email protected] [email protected] Abstract We construct a short group signature scheme. Signatures in our scheme are approximately the size of a standard RSA signature with the same security. Security of our group signature is based on the Strong Diffie-Hellman assumption and a new assumption in bilinear groups called the Decision Linear assumption. We prove security of our system, in the random oracle model, using a variant of the security definition for group signatures recently given by Bellare, Micciancio, and Warinschi. 1 Introduction Group signatures, introduced by Chaum and van Heyst [17], provide anonymity for signers. Any member of the group can sign messages, but the resulting signature keeps the identity of the signer secret. Often there is a third party that can undo the signature anonymity (trace) using a special trapdoor [17, 2]. Some systems support revocation [14, 4, 35, 19], where group membership can be selectively disabled without affecting the signing ability of unrevoked members. Currently, the most efficient constructions [2, 14, 4] are based on the Strong-RSA assumption introduced by Baric and Pfitzmann [5]. These signatures are usually much longer than RSA signatures of comparable security. A number of recent projects require properties provided by group signatures. One such project is the Trusted Computing effort [34] that, among other things, enables a desktop PC to prove to a remote party what software it is running via a process called attestation.