Software watermarking via opaque predicates: Implementation, analysis, and attacks

Abstract

Within the software industry software piracy is a great concern. In this article we address this issue through a prevention technique called software watermarking. Depending on how a software watermark is applied it can be used to discourage piracy; as proof of authorship or purchase; or to track the source of the illegal redistribution. In particular we analyze an algorithm originally proposed by Geneviève Arboit in A Method for Watermarking Java Programs via Opaque Predicates. This watermarking technique embeds the watermark by adding opaque predicates to the application. We have found that the Arboit technique does withstand some forms of attack and has a respectable data-rate. However, it is susceptible to a variety of distortive attacks. One unanswered question in the area of software watermarking is whether dynamic algorithms are inherently more resilient to attacks than static algorithms. We have implemented and empirically evaluated both static and dynamic versions within the SANDMARK framework.

An Evaluation of Dynamic Java Bytecode Software Watermarking Algorithms

“…Additive attack: In these attacks, another watermark is added by an adversary to the effectively watermarked system so as to provide reason to feel ambiguous about which watermark was included first [7].…”

Evaluating the WaterRpg software watermarking model on Java application programs

“…In fact, the mechanism actually modifies the conditions or expressions of these control statements by adding opaque predicates [12].…”

“…Although digital watermarking has made considerable progress and became a popular technique for copyright protection of multimedia information [8], research on software watermarking has recently received sufficient attention. The major software watermarking algorithms currently available are based on several techniques, among which are the register allocation [15], spread-spectrum [16], code re-orderings [13], opaque predicate [12], dynamic path techniques [3]; see also, Collberg and Nagra [6] for an exposition of the main results.…”

Watermarking Java application programs using the WaterRpg dynamic model

“…In fact, the mechanism actually modifies the conditions or expressions of these control statements by adding opaque predicates [4,13].…”

“…The software watermarking problem can be described as the problem of embedding a structure w into a program P such that w can be reliably located and extracted from P even after P has been subjected to code transformations such as translation, optimization and obfuscation [13].…”