This paper discusses key recovery and universal forgery attacks on several MAC algorithms based on universal hash functions. The attacks use a substantial number of verification queries but eventually allow for universal forgeries instead of existential or multiple forgeries. This means that the security of the algorithms completely collapses once a few forgeries are found. Some of these attacks start off by exploiting a weak key property, but turn out to become full-fledged divide and conquer attacks because of the specific structure of the universal hash functions considered. Partial information on a secret key can be exploited too, in the sense that it renders some key recovery attacks practical as soon as a few key bits are known. These results show that while universal hash functions offer provable security, high speeds and parallelism, their simple combinatorial properties make them less robust than conventional message authentication primitives.

https://lirias.kuleuven.be/bitstream/123456789/228630/2/article-1150.pdf

Key-Recovery Attacks on Universal Hash Function based MAC Algorithms

To effectively protect critical infrastructure facilities (CIF), it is important to understand the focus of cybersecurity efforts. The concept of building security systems based on a variety of models describing various CIF functioning aspects is presented.
The development of the concept is presented as a sequence of solving the following tasks. The basic concepts related to cyberattacks on CIF were determined, which make it possible to outline the boundaries of the problem and determine the level of formalization of the modeling processes. The proposed threat model takes into account possible synergistic/emergent features of the integration of modern target threats and their hybridity. A unified threat base that does not depend on CIF was formed. The concept of modeling the CIF security system was developed based on models of various classes and levels. A method to determine attacker's capabilities was developed. A concept for assessing the CIF security was developed, which allows forming a unified threat base, assessing the signs of their synergy and hybridity, identifying critical CIF points, determining compliance with regulatory requirements and the state of the security system. The mathematical tool and a variety of basic models of the concept can be used for all CIFs, which makes it possible to unify preventive measures and increase the security level. It is proposed to use post-quantum cryptography algorithms on crypto-code structures to provide security services. The proposed mechanisms provide the required stability (230–235 group operations), the rate of cryptographic transformation is comparable to block-symmetric ciphers (BSC) and reliability (Perr 10–9–10–12)

Development of a concept for building a critical infrastructure facilities security system

The subject of the research is a mathematical model of authentication of the transmitted message based on the McEliese scheme on shortened and elongated modified elliptic codes using the modified UMAC algorithm. The aim of this work is to develop such a scheme for the information exchange over Internet communication channels, which would ensure the proper level of verification and integrity of the transmitted information, taking into account the prevention of an increase in the costs of the actions taken. Tasks: analysis of existing ways to increase the resistance to hacking of transmitted messages over telecommunication networks; analysis of a message transfer scheme using blockchain technology; formalized description of a mathematical model for providing clear text authentication using a modified UMAC algorithm, as the formation of key data, a crypto-code construction (CCC) is used on the McEliese scheme on modified elliptic codes (MEС); development of data encryption and decryption algorithms using CCC based on McEliese on the MEC and UMAC algorithm. Аn approach was proposed to verify the authentication and verification of the information packet during transmission and reception via telecommunication channels, which allows using already known hashing methods to compare generated codegrams and transmitted messages for their correspondence, which increases the level of cryptographic stability of the transmitted data and the reliability of the received data. The developed schemes of algorithms for generating codеgrams and their decryption using the proposed approach make it possible to gradually demonstrate the implementation of procedures for generating codegrams and their hash codes using both shortening and lengthening the code. Further research should prove from a practical point of view the effectiveness of using this approach when transmitting a message regarding the preservation of its integrity and authenticity. Therefore, it is necessary to develop a test system that should implement the proposed approach, as well as evaluate the results obtained.

/pdf/matematichna-model-autentifikatsiyi-povidomlennia-shcho-2621c0eq8m.pdf

Математична модель аутентифікації повідомлення, що передається, на основі схеми мак-еліса на укорочених і подовження модифікованих еліптичних кодах з використанням модифікованого алгоритма umac

In this paper, we describe a new Niederreiter cryptosystem based on quasi-cyclic $\frac{m-1}{m}$ codes that is quantum-secure. This new cryptosystem has good transmission rate compared to the one using binary Goppa codes and uses smaller keys.

A Quantum-Secure Niederreiter Cryptosystem using Quasi-Cyclic Codes.

The quantum computer for accelerating image processing and strengthening the security of information systems

The use of the Niederreiter modified crypto-code structure (MCCS) with additional initialization vectors (with many invalid positional vectors of the error vector and multiple positions of shortening the error vector) requires an increase in the speed of cryptographic transformation of the system as a whole. For this purpose, it is proposed to use flawed codes. Flawed codes allow you to increase the speed of code transformations by reducing the power of the field while damaging the plaintext and reducing the amount of data transferred by damaging the ciphertext. This approach allows the construction of hybrid crypto-code structures based on the synthesis of Niederreiter modified crypto-code structures on modified (shortened or extended) codes on elliptic curves with damaging procedures. A significant difference from classical hybrid (complex) cryptosystems is the use of asymmetric cryptosystems to ensure data security with fast crypto-transformation procedures (generation and decoding of a codogram). The paper discusses methods for constructing flawed codes and approaches for using the Niederreiter hybrid crypto-code structure on modified elliptic codes. Practical algorithms are proposed for using the MV2 damage mechanism in the Niederreiter crypto-code structure on modified elliptic codes, which makes it possible to implement a hybrid crypto-code structure. The results of a comparative assessment of energy consumption for the formation of an information package with various methods of damage, which determined the choice of damage method in practical algorithms. The conducted studies confirm the competitive efficiency of the proposed cryptosystem in Internet technologies and mobile networks, ensuring practical implementation on modern platforms and the necessary cryptographic strength under post-quantum cryptography

/pdf/development-of-niederreiter-hybrid-crypto-code-structure-on-51e82kra94.pdf

Development of Niederreiter hybrid crypto-code structure on flawed codes

The development of computer technology has determined the vector for the expansion of services based on the Internet and “G” technologies. The main requirements for modern services in the banking sector are security and reliability. At the same time, security is considered not only as ensuring the confidentiality and integrity of transactions, but also their authenticity. However, in the post-quantum period, US NIST specialists question the durability of modern means of providing basic security services based on symmetric and asymmetric cryptography algorithms. The increase in computing resources allows attackers to use modern threats in combination. Thus, there is a need to search for new and/or modify known algorithms for generating MAC (message authentication codes). In addition, the growth of services increases the amount of information that needs to be authenticated. Among the well-known hash algorithms, the hash functions of universal hashing are distinguished, which allow initially determining the number of collisions and their uniform distribution over the entire set of hash codes. Possibilities of modifying the cascade hashing algorithm UMAC (message authentication code based on universal hashing, universal MAC) based on the use of McEliece crypto-code construction on algebrogeometric (elliptic codes (EC), modified elliptic codes (MEC) and damaged codes (DC). This approach allows preserving the uniqueness property, in contrast to the classical UMAC scheme based on a block symmetric cipher (AES). The presented algorithms for evaluating the properties of universality and strict universality of hash codes make it possible to evaluate the security of the proposed hashing constructs based on universal hash functions, taking into account the preservation of the universality property

/pdf/development-of-a-modified-umac-algorithm-based-on-crypto-3p6gzmh39w.pdf

Development of a modified umac algorithm based on crypto-code constructions

The development of decentralized systems and blockchain technology have expanded the range of cryptocurrency-based banking services. The main difference from the hierarchical structures of the organizations of the banking sector (national and commercial banks) is the formation of valid nodes ensuring the confirmation of transactions based on the checking and verification of digital signatures and MAC codes. The Bitcoin protocols use the SHA-256 algorithm to form MAC codes, however, the rapid growth of the system leads to significant time costs not only for mining, but also for validation of the formed blocks. The further development of decentralized systems, increase the number of wall-distributors and full nodes forces us to look for new ways to solve a temporary problem based on using different approaches to providing authentication in decentralized systems. The paper discusses the algorithm for generating UMAC message authentication codes using a McEliece’s crypto-code scheme based on the use of universal hashing functions. A reduced UMAC model (mini-UMAC) and a method for statistical analysis of the collision characteristics of the generated message authentication codes are proposed. Using the reduced UMAC model, collisional characteristics of authentication codes are investigated, it is shown that the use of cryptographic transformation (using the AES algorithm) at the final stage of UMAC leads to a violation of the universal hashing characteristics.

/pdf/development-of-authentication-codes-of-messages-on-the-basis-20wv12lhrh.pdf

Development of authentication codes of messages on the basis of umac with crypto-code mceliece’s scheme

The article analyzes construction of crypto-code designs (CCDs) on the basis of asymmetric Mac-Alice and Niederreiter crypto-code systems on elliptical (EC) and modified elliptic codes (MEC), which, in the conditions of post-quantum cryptography, allow to provide a guaranteed level of crypto stability, to counteract the modern Attacks and attack by V. Sidelnikov on the theoretical code schemes of McAlias and Niederreiter. Schemes of hybrid crypto-code designs constraction the lossy codes are addressed. Methods of constructing mechanisms of confidentiality and integrity of banking information resources under hybrid threats to security components (information security, cybersecurity, information security) are proposed. Using of a lossy code is suggested to this end. Lossy Code allow you to increase the speed of code changes by reducing the power of the field when causing damage to open text and reducing the amount of data transferred by causing harm to the cipher text. The methods of constructing unprofitable codes and approaches for use in hybrid KKK of McAlias and Niederreiter on modified elliptic codes are considered. Practical algorithms for the use of the MV2 mechanism in McAlias’ CCD and Niederreiter’s modified elliptic codes are proposed, which allows the implementation of the CCD hybrid scheme. The comparative results of the study of stability and power capacity with respect to their practical use in automated banking systems are presented.

/pdf/research-of-crypto-code-designs-construction-for-using-in-19afd1link.pdf

Alla Gavrilova

Papers

Development of Niederreiter hybrid crypto-code structure on flawed codes

Development of a modified umac algorithm based on crypto-code constructions

Development of authentication codes of messages on the basis of umac with crypto-code mceliece’s scheme

Research of crypto-code designs construction for using in post quantum cryptography