Criptografía ligera en internet de las cosas para la industria

La Criptografía Ligera o Liviana (Lightweight Cryptography) es uno de los temas de actualidad de la Criptología. Una gran variedad de algoritmos “livianos” han sido diseñados para garantizar Confidencialidad, Autenticidad e Integridad de los datos en dispositivos de lo que se ha dado en llamar Internet de las Cosas (IoT por sus siglas en inglés). Algunos de ellos surgen del ámbito académico y se aplican en la Industria; otros son propietarios, desarrollados por las empresas para satisfacer sus requerimientos de seguridad. En este trabajo se presenta el estado del arte de algunos de tales algoritmos empleados en diferentes dispositivos IoT. Se describen brevemente sus características criptológicas generales y se muestran los diferentes ataques a los que fueron sometidos. Finalmente se enumeran algunas de las tendencias para el diseño e implementación de dichas primitivas.VIII Workshop Seguridad informática.Red de Universidades con Carreras en Informátic

Criptografía ligera en internet de las cosas para la industria

La Criptografía Ligera o Liviana (Lightweight Cryptography) es uno de los temas de actualidad de la Criptología. Una gran variedad de algoritmos “livianos” han sido diseñados para garantizar Confidencialidad, Autenticidad e Integridad de los datos en dispositivos de lo que se ha dado en llamar Internet de las Cosas (IoT por sus siglas en inglés). Algunos de ellos surgen del ámbito académico y se aplican en la Industria; otros son propietarios, desarrollados por las empresas para satisfacer sus requerimientos de seguridad. En este trabajo se presenta el estado del arte de algunos de tales algoritmos empleados en diferentes dispositivos IoT. Se describen brevemente sus características criptológicas generales y se muestran los diferentes ataques a los que fueron sometidos. Finalmente se enumeran algunas de las tendencias para el diseño e implementación de dichas primitivas.VIII Workshop Seguridad informática.Red de Universidades con Carreras en Informátic

State of the Art in Lightweight Symmetric Cryptography

Lightweight cryptography has been one of the ``hot topics'' in symmetric cryptography in the recent years. A huge number of lightweight algorithms have been published, standardized and/or used in commercial products. In this paper, we discuss the different implementation constraints that a ``lightweight'' algorithm is usually designed to satisfy. We also present an extensive survey of all lightweight symmetric primitives we are aware of. It covers designs from the academic community, from government agencies and proprietary algorithms which were reverse-engineered or leaked. Relevant national (\nist{}...) and international (\textsc{iso/iec}...) standards are listed. We then discuss some trends we identified in the design of lightweight algorithms, namely the designers' preference for \arx{}-based and bitsliced-S-Box-based designs and simple key schedules. Finally, we argue that lightweight cryptography is too large a field and that it should be split into two related but distinct areas: \emph{ultra-lightweight} and \emph{IoT} cryptography. The former deals only with the smallest of devices for which a lower security level may be justified by the very harsh design constraints. The latter corresponds to low-power embedded processors for which the \aes{} and modern hash function are costly but which have to provide a high level security due to their greater connectivity

State of the Art in Lightweight Symmetric Cryptography

Lightweight cryptography has been one of the hot topics in symmetric cryptography in the recent years. A huge number of lightweight algorithms have been published, standardized and/or used in commercial products. In this paper, we discuss the different implementation constraints that a lightweight algorithm is usually designed to satisfy in both the software and the hardware case. We also present an extensive survey of all lightweight symmetric primitives we are aware of. It covers designs from the academic community, from government agencies and proprietary algorithms which were reverse-engineered or leaked. Relevant national (NIST...) and international (ISO/IEC...) standards are listed. We identified several trends in the design of lightweight algorithms, such as the designers\u27 preference for ARX-based and bitsliced-S-Box-based designs or simpler key schedules. We also discuss more general trade-offs facing the authors of such algorithms and suggest a clearer distinction between two subsets of lightweight cryptography. The first, ultra-lightweight cryptography, deals with primitives fulfilling a unique purpose while satisfying specific and narrow constraints. The second is ubiquitous cryptography and it encompasses more versatile algorithms both in terms of functionality and in terms of implementation trade-offs

Cryptanalysis, Reverse-Engineering and Design of Symmetric Cryptographic Algorithms

In this thesis, I present the research I did with my co-authors on several aspects of symmetric cryptography from May 2013 to December 2016, that is, when I was a PhD student at the university of Luxembourg under the supervision of Alex Biryukov. My research has spanned three different areas of symmetric cryptography. In Part I of this thesis, I present my work on lightweight cryptography. This field of study investigates the cryptographic algorithms that are suitable for very constrained devices with little computing power such as RFID tags and small embedded processors such as those used in sensor networks. Many such algorithms have been proposed recently, as evidenced by the survey I co-authored on this topic. I present this survey along with attacks against three of those algorithms, namely GLUON, PRINCE and TWINE. I also introduce a new lightweight block cipher called SPARX which was designed using a new method to justify its security: the Long Trail Strategy. Part II is devoted to S-Box reverse-engineering, a field of study investigating the methods recovering the hidden structure or the design criteria used to build an S-Box. I co-invented several such methods: a statistical analysis of the differential and linear properties which was applied successfully to the S-Box of the NSA block cipher Skipjack, a structural attack against Feistel networks called the yoyo game and the TU-decomposition. This last technique allowed us to decompose the S-Box of the last Russian standard block cipher and hash function as well as the only known solution to the APN problem, a long-standing open question in mathematics. Finally, Part III presents a unifying view of several fields of symmetric cryptography by interpreting them as purposefully hard. Indeed, several cryptographic algorithms are designed so as to maximize the code size, RAM consumption or time taken by their implementations. By providing a unique framework describing all such design goals, we could design modes of operations for building any symmetric primitive with any form of hardness by combining secure cryptographic building blocks with simple functions with the desired form of hardness called plugs. Alex Biryukov and I also showed that it is possible to build plugs with an asymmetric hardness whereby the knowledge of a secret key allows the privileged user to bypass the hardness of the primitive

Physical Security of Cryptographic Algorithm Implementations

This thesis deals with physical attacks on implementations of cryptographic algorithms and countermeasures against these attacks. Physical attacks exploit properties of an implementation to recover secret cryptographic keys. Particularly vulnerable to physical attacks are embedded devices. In the area of side-channel analysis, this thesis addresses attacks that exploit observations of power consumption or electromagnetic leakage of the device and target symmetric cryptographic algorithms. First, this work proposes a new combination of two well-known attacks that is more efficient than each of the attacks individually. Second, this work studies attacks exploiting leakage induced by microprocessor cache mechanism, suggesting an algorithm that can recover the secret key in the presence of uncertainties in cache event detection from side-channel acquisitions. Third, practical side-channel attacks are discovered against the AES engine of the AVR XMEGA, a recent versatile microcontroller. In the area of fault analysis, this thesis extends existing attacks against the RSA digital signature algorithm implemented with the Chinese remainder theorem to a setting where parts of the signed message are unknown to the attacker. The new attacks are applicable in particular to several widely used standards in modern smart card applications. In the area of countermeasures, this work proposes a new algorithm for random delay generation in embedded software. The new algorithm is more efficient than the previously suggested algorithms since it introduces more uncertainty for the attacker with less performance overhead. The results presented in this thesis are practically validated in experiments with general-purpose 8-bit AVR and 32-bit ARM microcontrollers that are used in many embedded devices

Cryptanalysis of the Atmel Cipher in SecureMemory, CryptoMemory and CryptoRF

SecureMemory (SM), CryptoMemory (CM) and CryptoRF (CR) are the Atmel chip families with wide applications in practice. They implement a proprietary stream cipher, which we call the Atmel cipher, to provide authenticity, confidentiality and integrity. At CCS’2010, it was shown that given 1 keystream frame, the secret key in SM protected by the simple version of the cipher can be recovered in 2^39.4 cipher ticks and if 2640 keystream frames are available, the secret key in CM guarded by the more complex version of the cipher can be restored in 2^58 cipher ticks. In this paper, we show much more efficient and practical attacks on both versions of the Atmel cipher. The idea is to dynamically reconstruct the internal state of the underlying register by exploiting the different diffusion speeds of the different cells. For SM, we can recover the secret key in 2^29.8 cipher ticks given 1 keystream frame; for CM, we can recover the secret key in 2^50 cipher ticks with around 24 frames. Practical implementation of the full attack confirms our results

XXV Congreso Argentino de Ciencias de la Computación - CACIC 2019: libro de actas

Trabajos presentados en el XXV Congreso Argentino de Ciencias de la Computación (CACIC), celebrado en la ciudad de Río Cuarto los días 14 al 18 de octubre de 2019 organizado por la Red de Universidades con Carreras en Informática (RedUNCI) y Facultad de Ciencias Exactas, Físico-Químicas y Naturales - Universidad Nacional de Río CuartoRed de Universidades con Carreras en Informátic

XXV Congreso Argentino de Ciencias de la Computación - CACIC 2019: libro de actas

Trabajos presentados en el XXV Congreso Argentino de Ciencias de la Computación (CACIC), celebrado en la ciudad de Río Cuarto los días 14 al 18 de octubre de 2019 organizado por la Red de Universidades con Carreras en Informática (RedUNCI) y Facultad de Ciencias Exactas, Físico-Químicas y Naturales - Universidad Nacional de Río CuartoRed de Universidades con Carreras en Informátic