Survey: Block Cipher Methods
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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. -
A Preliminary Empirical Study to Compare MPI and Openmp ISI-TR-676
A preliminary empirical study to compare MPI and OpenMP ISI-TR-676 Lorin Hochstein, Victor R. Basili December 2011 Abstract Context: The rise of multicore is bringing shared-memory parallelism to the masses. The community is struggling to identify which parallel models are most productive. Objective: Measure the effect of MPI and OpenMP models on programmer productivity. Design: One group of programmers solved the sharks and fishes problem using MPI and a second group solved the same problem using OpenMP, then each programmer switched models and solved the same problem again. The participants were graduate students in an HPC course. Measures: Development effort (hours), program correctness (grades), pro- gram performance (speedup versus serial implementation). Results: Mean OpenMP development time was 9.6 hours less than MPI (95% CI, 0.37 − 19 hours), a 43% reduction. No statistically significant difference was observed in assignment grades. MPI performance was better than OpenMP performance for 4 out of the 5 students that submitted correct implementations for both models. Conclusions: OpenMP solutions for this problem required less effort than MPI, but insufficient power to measure the effect on correctness. The perfor- mance data was insufficient to draw strong conclusions but suggests that unop- timized MPI programs perform better than unoptimized OpenMP programs, even with a similar parallelization strategy. Further studies are necessary to examine different programming problems, models, and levels of programmer experience. Chapter 1 INTRODUCTION In the high-performance computing community, the dominant parallel pro- gramming model today is MPI, with OpenMP as a distant but clear second place [1,2]. MPI’s advantage over OpenMP on distributed memory systems is well-known, and consequently MPI usage dominates in large-scale HPC sys- tems. -
Bruce Schneier 2
Committee on Energy and Commerce U.S. House of Representatives Witness Disclosure Requirement - "Truth in Testimony" Required by House Rule XI, Clause 2(g)(5) 1. Your Name: Bruce Schneier 2. Your Title: none 3. The Entity(ies) You are Representing: none 4. Are you testifying on behalf of the Federal, or a State or local Yes No government entity? X 5. Please list any Federal grants or contracts, or contracts or payments originating with a foreign government, that you or the entity(ies) you represent have received on or after January 1, 2015. Only grants, contracts, or payments related to the subject matter of the hearing must be listed. 6. Please attach your curriculum vitae to your completed disclosure form. Signatur Date: 31 October 2017 Bruce Schneier Background Bruce Schneier is an internationally renowned security technologist, called a security guru by the Economist. He is the author of 14 books—including the New York Times best-seller Data and Goliath: The Hidden Battles to Collect Your Data and Control Your World—as well as hundreds of articles, essays, and academic papers. His influential newsletter Crypto-Gram and blog Schneier on Security are read by over 250,000 people. Schneier is a fellow at the Berkman Klein Center for Internet and Society at Harvard University, a Lecturer in Public Policy at the Harvard Kennedy School, a board member of the Electronic Frontier Foundation and the Tor Project, and an advisory board member of EPIC and VerifiedVoting.org. He is also a special advisor to IBM Security and the Chief Technology Officer of IBM Resilient. -
Identifying Open Research Problems in Cryptography by Surveying Cryptographic Functions and Operations 1
International Journal of Grid and Distributed Computing Vol. 10, No. 11 (2017), pp.79-98 http://dx.doi.org/10.14257/ijgdc.2017.10.11.08 Identifying Open Research Problems in Cryptography by Surveying Cryptographic Functions and Operations 1 Rahul Saha1, G. Geetha2, Gulshan Kumar3 and Hye-Jim Kim4 1,3School of Computer Science and Engineering, Lovely Professional University, Punjab, India 2Division of Research and Development, Lovely Professional University, Punjab, India 4Business Administration Research Institute, Sungshin W. University, 2 Bomun-ro 34da gil, Seongbuk-gu, Seoul, Republic of Korea Abstract Cryptography has always been a core component of security domain. Different security services such as confidentiality, integrity, availability, authentication, non-repudiation and access control, are provided by a number of cryptographic algorithms including block ciphers, stream ciphers and hash functions. Though the algorithms are public and cryptographic strength depends on the usage of the keys, the ciphertext analysis using different functions and operations used in the algorithms can lead to the path of revealing a key completely or partially. It is hard to find any survey till date which identifies different operations and functions used in cryptography. In this paper, we have categorized our survey of cryptographic functions and operations in the algorithms in three categories: block ciphers, stream ciphers and cryptanalysis attacks which are executable in different parts of the algorithms. This survey will help the budding researchers in the society of crypto for identifying different operations and functions in cryptographic algorithms. Keywords: cryptography; block; stream; cipher; plaintext; ciphertext; functions; research problems 1. Introduction Cryptography [1] in the previous time was analogous to encryption where the main task was to convert the readable message to an unreadable format. -
A New Simple Block Cipher
FrankenCipher: A New Simple Block Cipher 1 2 Gerardus Samudra Sembiring , Nathaniel Evan Gunawan . 1,2 Program Studi Teknik Informatika, Sekolah Teknik Elektro dan Informatika (STEI), Institut Teknologi Bandung (ITB), Jalan Ganesha 10, Bandung 40132 E-mail: [email protected], [email protected] Abstract. Encryption, the process to obfuscate information deemed confidential or private, while dating back to the days of Ancient Greece and Rome, has now rapidly risen in complexity and prominence, thanks to the development of modern technology. We will now take a look at several modern block cipher encryption algorithms, and propose our own block cipher encryption algorithm, applying in it the Feistel structure, confusion and diffusion, substitution and transposition, and iterated ciphers. Keywords: encryption, block cipher, Feistel, confusion, diffusion. 1. Introduction In this paper, we would like to propose a new, simple block cipher titled FrankenCipher. FrankenCipher arises out of the need for a block cipher that is more performant, yet maintains the level of security that historically well-established block ciphers such as DES offer. To achieve this, we combine the unbalanced Feistel network implemented in MacGuffin, a 64-bit block cipher, and the key scheduling algorithm of RC4 for the S-block, and the structure of Twofish. 2. Theoretical Framework 2.1. Block ciphers A block cipher is an encryption technique that operates on the block level. To encrypt a plain text with a block cipher, the plaintext is split into multiple blocks of n-bits. The block cipher then proceeds to encrypt each block to produce a cipher block, utilising a fixed, symmetric key; that is, the same key is used for both the encryption and decryption process. -
Encryption Block Cipher
10/29/2007 Encryption Encryption Block Cipher Dr.Talal Alkharobi 2 Block Cipher A symmetric key cipher which operates on fixed-length groups of bits, termed blocks, with an unvarying transformation. When encrypting, a block cipher take n-bit block of plaintext as input, and output a corresponding n-bit block of ciphertext. The exact transformation is controlled using a secret key. Decryption is similar: the decryption algorithm takes n-bit block of ciphertext together with the secret key, and yields the original n-bit block of plaintext. Mode of operation is used to encrypt messages longer than the block size. 1 Dr.Talal Alkharobi 10/29/2007 Encryption 3 Encryption 4 Decryption 2 Dr.Talal Alkharobi 10/29/2007 Encryption 5 Block Cipher Consists of two algorithms, encryption, E, and decryption, D. Both require two inputs: n-bits block of data and key of size k bits, The output is an n-bit block. Decryption is the inverse function of encryption: D(E(B,K),K) = B For each key K, E is a permutation over the set of input blocks. n Each key K selects one permutation from the possible set of 2 !. 6 Block Cipher The block size, n, is typically 64 or 128 bits, although some ciphers have a variable block size. 64 bits was the most common length until the mid-1990s, when new designs began to switch to 128-bit. Padding scheme is used to allow plaintexts of arbitrary lengths to be encrypted. Typical key sizes (k) include 40, 56, 64, 80, 128, 192 and 256 bits. -
A Brief Outlook at Block Ciphers
A Brief Outlook at Block Ciphers Pascal Junod Ecole¶ Polytechnique F¶ed¶eralede Lausanne, Suisse CSA'03, Rabat, Maroc, 10-09-2003 Content F Generic Concepts F DES / AES F Cryptanalysis of Block Ciphers F Provable Security CSA'03, 10 septembre 2003, Rabat, Maroc { i { Block Cipher P e d P C K K CSA'03, 10 septembre 2003, Rabat, Maroc { ii { Block Cipher (2) F Deterministic, invertible function: e : {0, 1}n × K → {0, 1}n d : {0, 1}n × K → {0, 1}n F The function is parametered by a key K. F Mapping an n-bit plaintext P to an n-bit ciphertext C: C = eK(P ) F The function must be a bijection for a ¯xed key. CSA'03, 10 septembre 2003, Rabat, Maroc { iii { Product Ciphers and Iterated Block Ciphers F A product cipher combines two or more transformations in a manner intending that the resulting cipher is (hopefully) more secure than the individual components. F An iterated block cipher is a block cipher involving the sequential repeti- tion of an internal function f called a round function. Parameters include the number of rounds r, the block bit size n and the bit size k of the input key K from which r subkeys ki (called round keys) are derived. For invertibility purposes, the round function f is a bijection on the round input for each value ki. CSA'03, 10 septembre 2003, Rabat, Maroc { iv { Product Ciphers and Iterated Block Ciphers (2) P K f k1 f k2 f kr C CSA'03, 10 septembre 2003, Rabat, Maroc { v { Good and Bad Block Ciphers F Flexibility F Throughput F Estimated Security Level CSA'03, 10 septembre 2003, Rabat, Maroc { vi { Data Encryption Standard (DES) F American standard from (1976 - 1998). -
The Block Cipher SC2000
The Block Cipher SC2000 Takeshi Shimoyama1, Hitoshi Yanami1, Kazuhiro Yokoyama1, Masahiko Takenaka2, Kouichi Itoh2, Jun Yajima2, Naoya Torii2, and Hidema Tanaka3 1 Fujitsu Laboratories LTD. 4-1-1, Kamikodanaka Nakahara-ku Kawasaki 211-8588, Japan {shimo,yanami,kayoko}@flab.fujitsu.co.jp 2 Fujitsu Laboratories LTD. 64, Nishiwaki, Ohkubo-cho, Akashi 674-8555, Japan {takenaka,kito,jyajima,torii}@flab.fujitsu.co.jp 3 Science University of Tokyo Yamazaki, Noda, Chiba, 278 Japan [email protected] Abstract. In this paper, we propose a new symmetric key block cipher SC2000 with 128-bit block length and 128-,192-,256-bit key lengths. The block cipher is constructed by piling two layers: one is a Feistel structure layer and the other is an SPN structure layer. Each operation used in two layers is S-box or logical operation, which has been well studied about security. It is a strong feature of the cipher that the fast software implementations are available by using the techniques of putting together S-boxes in various ways and of the Bitslice implementation. 1 Introduction In this paper, we propose a new block cipher SC2000. The algorithm has 128-bit data inputs and outputs and 128-bit, 192-bit, and 256-bit keys can be used. Our design policy for the cipher is to enable high-speed in software and hardware processing on various platforms while maintaining the high-level security as ci- pher. The cipher is constructed by piling a Feistel and an SPN structures with S-boxes for realizing those properties. For evaluation of security, we inspect the security in the design against dif- ferential attacks, linear attacks, higher order differential attacks, interpolation attacks, and so on. -
AES3 Presentation
Cryptanalytic Progress: Lessons for AES John Kelsey1, Niels Ferguson1, Bruce Schneier1, and Mike Stay2 1 Counterpane Internet Security, Inc., 3031 Tisch Way, 100 Plaza East, San Jose, CA 95128, USA 2 AccessData Corp., 2500 N University Ave. Ste. 200, Provo, UT 84606, USA 1 Introduction The cryptanalytic community is currently evaluating five finalist algorithms for the AES. Within the next year, one or more ciphers will be chosen. In this note, we argue caution in selecting a finalist with a small security margin. Known attacks continuously improve over time, and it is impossible to predict future cryptanalytic advances. If an AES algorithm chosen today is to be encrypting data twenty years from now (that may need to stay secure for another twenty years after that), it needs to be a very conservative algorithm. In this paper, we review cryptanalytic progress against three well-regarded block ciphers and discuss the development of new cryptanalytic tools against these ciphers over time. This review illustrates how cryptanalytic progress erodes a cipher’s security margin. While predicting such progress in the future is clearly not possible, we claim that assuming that no such progress can or will occur is dangerous. Our three examples are DES, IDEA, and RC5. These three ciphers have fundamentally different structures and were designed by entirely different groups. They have been analyzed by many researchers using many different techniques. More to the point, each cipher has led to the development of new cryptanalytic techniques that not only have been applied to that cipher, but also to others. 2 DES DES was developed by IBM in the early 1970s, and standardized made into a standard by NBS (the predecessor of NIST) [NBS77]. -
Basic Cryptanalysis Methods on Block Ciphers
1 BASIC CRYPTANALYSIS METHODS ON BLOCK CIPHERS A THESIS SUBMITTED TO THE GRADUATE SCHOOL OF APPLIED MATHEMATICS OF MIDDLE EAST TECHNICAL UNIVERSITY BY DILEK˙ C¸ELIK˙ IN PARTIAL FULFILLMENT OF THE REQUIREMENTS FOR THE DEGREE OF MASTER OF SCIENCE IN CRYPTOGRAPHY MAY 2010 Approval of the thesis: BASIC CRYPTANALYSIS METHODS ON BLOCK CIPHERS submitted by DILEK˙ C¸ELIK˙ in partial fulfillment of the requirements for the degree of Master of Science in Department of Cryptography, Middle East Technical University by, Prof. Dr. Ersan AKYILDIZ Director, Graduate School of Applied Mathematics Prof. Dr. Ferruh OZBUDAK¨ Head of Department, Cryptography Assoc. Prof. Dr. Ali DOGANAKSOY˘ Supervisor, Department of Mathematics, METU Examining Committee Members: Prof. Dr. Ferruh OZBUDAK¨ Department of Mathematics, METU Assoc. Prof. Dr. Ali DOGANAKSOY˘ Department of Mathematics, METU Assist. Prof. Dr. Zulf¨ ukar¨ SAYGI Department of Mathematics, TOBB ETU Dr. Muhiddin UGUZ˘ Department of Mathematics, METU Dr. Murat CENK Department of Cryptography, METU Date: I hereby declare that all information in this document has been obtained and presented in accordance with academic rules and ethical conduct. I also declare that, as required by these rules and conduct, I have fully cited and referenced all material and results that are not original to this work. Name, Last Name: DILEK˙ C¸ELIK˙ Signature : iii ABSTRACT BASIC CRYPTANALYSIS METHODS ON BLOCK CIPHERS C¸elik, Dilek M.S., Department of Cryptography Supervisor : Assoc. Prof. Dr. Ali DOGANAKSOY˘ May 2010, 119 pages Differential cryptanalysis and linear cryptanalysis are the first significant methods used to at- tack on block ciphers. These concepts compose the keystones for most of the attacks in recent years. -
Applying Conditional Linear Cryptanalysis to Ciphers with Key- Dependant Operations
Applying Conditional Linear Cryptanalysis to Ciphers with Key- Dependant Operations REINER DOJEN TOM COFFEY Data Communications Security Laboratory Department of Electronic and Computer Engineering University of Limerick IRELAND Abstract: - Linear cryptanalysis has been proven to be a powerful attack that can be applied to a number of symmetric block ciphers. However, conventional linear cryptanalysis is ineffective in attacking ciphers that use key-dependent operations, such as ICE, Lucifer and SAFER. In this paper conditional linear cryptanalysis, which uses characteristics that depend on some key-bit values, is introduced. This technique and its application to symmetric ciphers are analysed. The consequences of using key-dependent characteristics are explained and a formal notation of conditional linear cryptanalysis is presented. As a case study, conditional linear cryptanalysis is applied to the ICE cipher, which uses key-dependant operations to improve resistance against cryptanalysis. A successful attack on ThinICE using the new technique is presented. Further, experimental work supporting the effectiveness of conditional linear cryptanalysis is also detailed., Key-Words: - Cryptography, Cryptanalysis, Linear cryptanalysis, Symmetric ciphers, Attack 1 Introduction In contrast to differential cryptanalysis, linear As the volume of data transmitted over the world's cryptanalysis uses linear approximations to describe expanding communication networks increases so the F-function of a block cipher. Thus, if some also does the demand for data security services such plaintext bits and ciphertext bits are XORed as confidentiality and integrity. This protection can together, then the result equals the XOR of some be achieved by using either a public key cipher or a bits of the key (with a probability p, for the key) and symmetric cipher. -
ACUSON SC2000TM Volume Imaging Ultrasound System
ACUSON SC2000TM Volume Imaging Ultrasound System XXXXXXXXXXXXxxXXXXXXXXXXXXXXXXXXXX DICOM Conformance Statement Version VA16D, VA16E 30-Sept-2011 © Siemens Healthcare 2011 All rights reserved Siemens Healthcare, Henkestr. 127, D-91052 Erlangen, Germany Headquarters: Berlin and Munich Siemens AG, Wittelsbacher Platz 2, D-80333 Munich, Germany ACUSON SC2000TM is a trademark of Siemens Healthcare. TM ACUSON SC2000 Volume Imaging Ultrasound System DICOM Conformance Statement CONFORMANCE STATEMENT OVERVIEW The ACUSON SC2000TM Volume Imaging Ultrasound System supports the following DICOM Application Entities: - Verification o Verification AE - Transfer o Storage AE o Storage Commitment AE - Query / Retrieve o Query AE o Retrieve AE - Workflow Management o Worklist AE o MPPS AE Table 1. NETWORK SERVICES Service Class User Service Class Provider SOP Classes (SCU) (SCP) VERIFICATION Verification AE Verification Yes Yes TRANSFER Storage AE Ultrasound Image Storage Yes Yes Ultrasound Multi-frame Image Storage Yes Yes Secondary Capture Image Storage Yes Yes Comprehensive SR Yes Yes Raw Data Storage Yes Yes Storage Commitment AE Storage Commitment Push Model Yes No QUERY / RETRIEVE Query AE Study Root Query/Retrieve Information Model – FIND Yes No Retrieve AE Study Root Query/Retrieve Information Model – MOVE Yes No WORKFLOW MANAGEMENT Worklist AE Modality Worklist Yes No MPPS AE MPPS (N-Create, N-Set) Yes No © Siemens Healthcare, 2011 Version VA16D/E Page 2 of 111 TM ACUSON SC2000 Volume Imaging Ultrasound System DICOM Conformance Statement Table