Encryption Methods and Algorithms Based on Domestic Standards in Open-Source Operating Systems

Abstract

The paper describes the principles and methods underlying the creation of an application in secure operating systems, which provides reliable data encryption. The research aims to analyze and indicate the specifics of encryption methods and algorithms based on domestic standards in open-source operating systems. Cryptanalysis was used in the article, as this avoids vulnerabilities identified in previously created implementations. In the article, the authors draw attention to the fact that 7-Zip uses CBC encryption (concatenation of encrypted text blocks), but the Counter Mode is supported. The same support was provided in the encrypt implementation. Since the key expansion function initially fills the special array created by p7zip with round keys using a unique property of the domestic standard, only one round encryption function was created (performed both during encryption and decryption). This method is also used in various modes. In many cases, initialization time deviations depending on the selected mode are insignificant. The created cryptographic module was tested to meet the domestic standard, which contains several test cases. It was confirmed during the tests that the created module implements the algorithm of the domestic standard. The article shows a way to implement a fairly convenient graphical interface for accessing the cryptographic module, which enables the user not to call the command line and remember the sequence and types of parameters passed to p7zip. This implementation also takes into account the verification of the correctness of decryption and the reading of other error codes.

Counter-Offset mode: A new paradigm in resisting differential cryptanalysis

“…The ECB and CBC have been foundational, with the ECB's simplicity being offset by its vulnerability to pattern analysis due to identical plaintext blocks producing identical ciphertext blocks [5]. CBC mode improved security by introducing data dependency through the XOR operation with the previous ciphertext block, although it also required careful management of initialization vectors (IVs) to prevent attacks [6]. The advent of CTR mode brought a paradigm shift with operations, highlighting the importance of non-repeating counters for maintaining security [7].…”