DOI: 10.7256/2306-4196.2016.5.18686

Abstract: The object of the study is technology of hiding method calls. Hidden calls are need to hide: entity dependencies; data processing logic; algorithms. The methods used to complete the task are limited by language technologies and its performance. Method can be called directly and indirectly: via the bootstrap method; from native code (JNI); using Reflection; using JRE 1.7, InvokeDynamic. The examples with source code are given. The authors conclude that the most promising methods among considered is invokedynamic technology. The study  present analysis of such methods as the bootstrap method, calling method from through native code, obfuscation calls via Reflection and InvokeDynamic. The article discusses various ways to conceal the method invocation. The characteristic features of obfuscation for most popular ones are reviewed. The most promising among the discussed methods is  invokedynamic technology. It allows completely removing method signature from the source code, leaving only the service information for the bootstrap method. With proper implementation of the bootstrap method it is possible to create bytecode, which will be impossible to decompile into valid Java code, Groovy's or Scala.

DOI: 10.7256/2306-4196.2013.3.9356

Abstract: The paper deals with the algorithm of Chenxi Wang’s, shows are the main disadvantages of this algorithm. The authors suggest the ways of modification to improve it. The algorithm of Chenxi Wang's is one of the most famous. The input data for the algorithm is the usual procedure, written in high level language. The authors describe the three stages of obfuscation of any such procedure. In the classic version of Chenxi Wang's the algorithm has poor stability. The authors suggest ways to improve stability of the algorithm, present modified version of the algorithm and reviews results of its implementation. The authors compare the source code and the resulting code and conclude that it is almost impossible to establish their functional identity and the logic of the program code is very difficult to understand using obfuscated source. Sometimes this can be done using the examples run of the resulting source code. This implies that after eliminating the shortcomings the algorithm is quite effective.

Abstract: Modern computer technology makes it a variety of tasks relevant to the field of information security. For example, for the protection of copyright in the images methods of steganography are used. To solve the problem of proving authorship (or vice versa) code obfuscation techniques are used. Obfuscation (from Lat. Obfuscare - obscure, obfuscate, and English. Obfuscate - make non-obvious, confusing, confusing) or obfuscated code - is the process of bringing the source code or executable program code to the form, that keeps its functionality, but complicates the analysis, understanding algorithms and modification during decompilation. Currently, there are special programs called obfuscators that performes obfuscation to solve the task in different ways. The article discusses the techniques of obfuscation from the most basic to sophisticated polymorphic generators obfuscators performing the mathematical transformation of the code, as well as the relationship of obfuscation and efficiency of program code execution and reduce the size of the program. The authors describe further development of obfuscation techniques.